WorldWideScience

Sample records for surface pigment concentrations

  1. Melanin pigmented solar absorbing surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Gallas, J.M.; Eisner, M.

    1980-01-01

    Selectivity enhancement is shown to result for melanin, a black biopolymer pigment, for sufficiently low sample density. The effect is proposed to follow from a consideration of the evanescent waves associated with the total internal reflection phenomenon. A relationship is discussed among powder density, pH and the paramagnetic properties of melanin; this relationship is shown to be consistent with, and offer support to an amino-acid side group proposed earlier as part of the melanin structure. A brief discussion is also presented on the optical properties of melanin and the relative importance of quinhydrone, a change transfer complex believed to exist in the polymeric structure of melanin.

  2. Phytoplankton pigments from the Nimbus-7 Coastal Zone Color Scanner - Comparisons with surface measurements

    Science.gov (United States)

    Gordon, H. R.; Clark, D. K.; Hovis, W. A.; Mueller, J. L.

    1980-01-01

    Algorithms are developed for removing aerosol effects in visual data from the Nimbus-7 Coastal Zone Color Scanner (CZCS). The corrected imagery reveals eddy-like ocean circulation patterns. Pigment concentrations from CZCS are compared with surface determinations. CZCS imagery estimates pigment concentration to within 0.5 log C, where C is the sum of the concentrations of chlorophyll a and phaeopigments a

  3. Effect of pigment concentration on fastness and color values of thermal and UV curable pigment printing

    Science.gov (United States)

    Baysal, Gulcin; Kalav, Berdan; Karagüzel Kayaoğlu, Burçak

    2017-10-01

    In the current study, it is aimed to determine the effect of pigment concentration on fastness and colour values of thermal and ultraviolet (UV) curable pigment printing on synthetic leather. For this purpose, thermal curable solvent-based and UV curable water-based formulations were prepared with different pigment concentrations (3, 5 and 7%) separately and applied by screen printing technique using a screen printing machine. Samples printed with solvent-based formulations were thermally cured and samples printed with water-based formulations were cured using a UV curing machine equipped with gallium and mercury (Ga/Hg) lamps at room temperature. The crock fastness values of samples printed with solvent-based formulations showed that increase in pigment concentration was not effective on both dry and wet crock fastness values. On the other hand, in samples printed with UV curable water-based formulations, dry crock fastness was improved and evaluated as very good for all pigment concentrations. However, increasing the pigment concentration affected the wet crock fastness values adversely and lower values were observed. As the energy level increased for each irradiation source, the fastness values were improved. In comparison with samples printed with solvent-based formulations, samples printed with UV curable water-based formulations yielded higher K/S values at all pigment concentrations. The results suggested that, higher K/S values can be obtained in samples printed with UV curable water-based formulations at a lower pigment concentration compared to samples printed with solvent-based formulations.

  4. The analysis of pigments on rock surfaces

    International Nuclear Information System (INIS)

    Fankhauser, B.; O'Connor, S.; Pittelkow, Y.

    1997-01-01

    A limestone slab of roof fall coated with a red pigment was recovered from a Rockshelter in the Napier Ranges of the Kimberley region, Western Australia. Next to the roof fall fragment in the same stratigraphic layer was a piece of ochre. Three questions were presented: (1) is the red substance an ochre? (2) is the piece of ochre identical to the red substance on the roof fall? and (3) are the layers of pigment on the top and bottom of the limestone slab the same? In addition, as an extension from these questions, a general method was developed for the in situ analysis of ochre pigments on substrates to determine likely compositions and ochre sources. The analysis of the red pigment presented an analytical problem because the substance was intimately associated with the rock slab and therefore the analysis had to be done in situ. Not only was the red layer thin, but on a micro level it was uneven. Energy dispersive x-ray analysis (EDXA) penetrated the red layer, simultaneously analysing this layer and the rock substrate to different degrees depending upon the thickness of the red layer. Determining if the substance was actually ochre involved a comparison of elemental analyses between the background (slab) and background with red coating. Coatings of other ochres with known elemental concentrations on the same limestone background gave a comparison of the effect of simultaneously analysing a thin layer and background with different compositions. Three graphical methods useful for insitu analysis are demeonstrated. The find dates (around 40,000 BP) add to a growing body of data in support of the widespread use of ochre accompanying the earliest documented use of widely separated and environmentally diverse regions of Australia by Aboriginal people

  5. Response surface optimization of the ultrasonic-assisted extraction of edible brown pigment from Macadamia shells

    Science.gov (United States)

    Liu, Y. Y.; Liu, Y. J.; Gong, X.; Li, J. H.

    2017-09-01

    The ultrasonic extraction of Edible brown pigment from macadamia shells was researched using response surface methodology (RSM) with 3 factors and 3 levels. A Box-Behnken design (BBD) was employed to investigate the effects of Solvent concentration, ratio of water to raw material and extraction time on the extraction yield of brown pigment. By using this new method, the optimum extraction condition was obtained as follows: Ultrasonic treating time 71 min, solvent to sample ratio of 23 mL/g, Alcohol concentrations 62%. Under the optimized condition, the experimental yield of brown pigment was 0.636g.

  6. Trends in Pinus ponderosa foliar pigment concentration due to chronic exposure of ozone and acid rain

    International Nuclear Information System (INIS)

    Neuman, L.; Houpis, J.; Anderson, P.

    1991-01-01

    To determine the effects of ozone and acid rain on mature Ponderosa pine trees, Lawrence Livermore National Lab. has collaborated with University of California Berkeley, University of California Davis, California State University Chico, and the US Forest Service at the latter's Chico Tree Improvement Center. Foliar tissue from mature grafted scions of Pinus ponderosa were exposed to two times ambient ozone for ten months and to acid rain (3.0 pH) weekly for 10 weeks using branch exposure chambers. Pigment extracts were analyzed spectrophotometrically for concentrations of chlorophylls a and b, and carotenoid pigments, at 662 nm, 644 nm, and 470 nm, respectively. Pigment concentrations were expressed on a surface area basis. Preliminary results revealed that chlorophyll a showed a downward trend due to the ozone treatment. Acid rain caused no effects on these three pigments, however, chlorophyll b showed an upward trend due to the interaction of ozone and acid rain. The carotenoid pigments showed no changes due to the treatments either singly, or in combination

  7. Study of plant pigment concentration using synchronous luminescence spectroscopy

    International Nuclear Information System (INIS)

    Pawar, B.H.; Raghuvanshi, F.C.; Mahalle, N.S.; Munde, B.S.; Devhade, S.K.; Arsad, S.S.; Kadam, K.P.; Pachkawade, A.P.; Hiswankar, S.U.

    2006-01-01

    We have recorded the SL (Synchronous Luminescence) spectra emitted by several plant leaves. We investigate in detail SL spectra emitted by the leaf of the plants like Hibiscus Schizopetalus, Ficus Benghalensis, Ficus Religiosa and Ficus Glomerata and study the concentration of the pigments in the plant leaves and the mechanism of photosynthesis process taking place in the leaves. The SL spectra have several features which may help in revealing the density and structure of the molecules present in the samples. The SL spectra exhibit two, three, four and five peaked structure. The peak appear at different wavelengths and their spectral widths are also different. The chlorophyll, xanthophyll and carotene concentration may be obtained from the study of the spectra. The plant species may be identified from the study of SL spectroscopy. (author)

  8. Enhancing the chroma of pigmented polymers using antireflective surface structures

    DEFF Research Database (Denmark)

    Clausen, Jeppe Sandvik; Christiansen, Alexander Bruun; Kristensen, Anders

    2013-01-01

    In this paper we investigate how the color of a pigmented polymer is affected by reduction of the reflectance at the air-polymer interface. Both theoretical and experimental investigations show modified diffuse-direct reflectance spectra when the reflectance of the surface is lowered. Specifically...

  9. Estimating water stressed dwarf green bean pigment concentration through hyperspectral indices

    International Nuclear Information System (INIS)

    Koksal, E.S.; Ustrun, H.; Ozcan, H.; Gunturk, A.

    2010-01-01

    In this study, the relationship between leaf pigment concentration (analyzed in the laboratory) and four spectral indexes (measured in the field) was investigated. For this purpose, field experiments consisting of six different irrigation treatments were conducted with dwarf green beans during 2005 growing season. Based on spectral data, spectral indexes were plotted against pigment concentration. Results showed that under water stress, the chlorophyll and carotene contents of green bean leaves rose. According to linear regression analysis between spectral indexes and pigment contents, the Normalized Difference Pigment Chlorophyll Index (NPCI) and Normalized Difference Vegetation Index (NDVI) had the highest correlations with the chlorophyll (a, b and total), and carotene content of leaves. (author)

  10. An Inverse Modeling Approach to Estimating Phytoplankton Pigment Concentrations from Phytoplankton Absorption Spectra

    Science.gov (United States)

    Moisan, John R.; Moisan, Tiffany A. H.; Linkswiler, Matthew A.

    2011-01-01

    Phytoplankton absorption spectra and High-Performance Liquid Chromatography (HPLC) pigment observations from the Eastern U.S. and global observations from NASA's SeaBASS archive are used in a linear inverse calculation to extract pigment-specific absorption spectra. Using these pigment-specific absorption spectra to reconstruct the phytoplankton absorption spectra results in high correlations at all visible wavelengths (r(sup 2) from 0.83 to 0.98), and linear regressions (slopes ranging from 0.8 to 1.1). Higher correlations (r(sup 2) from 0.75 to 1.00) are obtained in the visible portion of the spectra when the total phytoplankton absorption spectra are unpackaged by multiplying the entire spectra by a factor that sets the total absorption at 675 nm to that expected from absorption spectra reconstruction using measured pigment concentrations and laboratory-derived pigment-specific absorption spectra. The derived pigment-specific absorption spectra were further used with the total phytoplankton absorption spectra in a second linear inverse calculation to estimate the various phytoplankton HPLC pigments. A comparison between the estimated and measured pigment concentrations for the 18 pigment fields showed good correlations (r(sup 2) greater than 0.5) for 7 pigments and very good correlations (r(sup 2) greater than 0.7) for chlorophyll a and fucoxanthin. Higher correlations result when the analysis is carried out at more local geographic scales. The ability to estimate phytoplankton pigments using pigment-specific absorption spectra is critical for using hyperspectral inverse models to retrieve phytoplankton pigment concentrations and other Inherent Optical Properties (IOPs) from passive remote sensing observations.

  11. Primary description of surface water phytoplankton pigment patterns in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Naik, R.K.; Anil, A.C.; Narale, D.D.; Chitari, R.R.; Kulkarni, V.V.

    Spatial and temporal variations in surface water phytoplankton pigment distribution in the Bay of Bengal were studied during the spring intermonsoon (SpIM, February–April) and the commencement of the summer monsoon (CSM, May–June), using pigment...

  12. The effect of a red leaf pigment on the relationship between red edge and chlorophyll concentration

    Science.gov (United States)

    Curran, Paul J.; Dungan, Jennifer L.; Macler, Bruce A.; Plummer, Stephen E.

    1991-01-01

    The effect of a leaf pigment - red amaranthin - on red edge and chlorophyll concentration is investigated in amaranth leaves by means of treatments with nitrate and salts. A near-linear relationship between red edge and chlorophyll concentration is observed for leaves with low amaranthin concentration, and no relationship is noted at high concentrations. The study demonstrates the limitation inherent in estimating chlorophyll concentration by using remotely sensed red edge.

  13. Macular pigment density in relation to serum and adipose tissue concentrations of lutein and serum concentrations of zeaxanthin

    NARCIS (Netherlands)

    Broekmans, W.M.R.; Berendschot, T.T.J.R.; Klöpping-Ketelaars, I.A.A.; Vries, A.J. de; Goldbohm, R.A.; Tijburg, L.B.M.; Kardinaal, A.F.M.; Poppel, G. van

    2002-01-01

    Background: Macular pigment (MP), concentrated in the central area of the retina, contains the carotenoids lutein and zeaxanthin. A low MP density could be a risk factor for age-related macular degeneration. Little information is available regarding MP density in relation to serum lutein and

  14. Characterization of pigment-leached antifouling coatings using BET surface area measurements and mercury porosimetry

    DEFF Research Database (Denmark)

    Kiil, Søren; Dam-Johansen, Kim

    2007-01-01

    In this work BET surface area measurements and mercury porosimetry are used to characterize leached layers formed when seawater-soluble pigments (Cu2O and ZnO) dissolve during accelerated leaching of simple antifouling coatings. Measurements on single-pigment coatings show that an increasing...

  15. Optimizing conditions for the extraction of pigments in cochineals (Dactylopius coccus Costa) using response surface methodology.

    Science.gov (United States)

    González, Mónica; Méndez, Jesús; Carnero, Aurelio; Lobo, M Gloria; Afonso, Ana

    2002-11-20

    A simple method was developed for the extraction and determination of color pigments in cochineals (Dactylopius coccus Costa). The procedure was based on the solvent extraction of pigments in insect samples using methanol:water (65:35, v:v) as extractant. Two-level factorial design was used in order to optimize the solvent extraction parameters: temperature, time, methanol concentration in the extractant mixture, and the number of extractions. The results suggest that the number of extractions is statistically the most significant factor. The separation and determination of the pigments was carried out by high-performance liquid chromatography with UV-visible detection. Because the absorption spectra of different pigments are different in the visible region, it is convenient to use a diode array detector to obtain chromatographic profiles that allow for the characterization of the extracted pigments.

  16. Microstudies on thermal and UV treated silicone-acrylic paints with different pigment volume concentrations

    International Nuclear Information System (INIS)

    Chew, K.W.; Abdul Kariem Arof; Yahaya, A.H.; Yahya, R.; Puteh, R.

    2002-01-01

    The effect of pigment volume concentration (PVC) on morphology of pigment particles employed in the silicone-acrylic compositions suitable for high temperature corrosion protection application, has been investigated using SEM. Silicone-acrylic based paints with 50% silicone resin have been selected to prepare paints with PVC values from 10% to 60%. The paints were applied on mild steel panels of size of 5 cm x 7.5 cm. After curing for one week, the panels were subjected to 24 hours of heating ranging from room temperature up to 300 degree C and 400 hours of UV weathering. After the corrosion test, SEM micrographs were taken to investigate the gloss, rusting and adhesion properties of the coating films. (Author)

  17. Pigment colors printing on cotton fabrics by surface coating induced by electron beam and thermal curing

    International Nuclear Information System (INIS)

    El-Naggar, Abdel Wahab M.; Zohdy, Maged H.; Said, Hossam M.; El-Din, Mahmoud S.; Noval, Dalia M.

    2005-01-01

    Cotton fabrics were coated from one surface with different pigment colors incorporated in formulations containing ethylene glycol (EG), methyl methacrylate (MMA) and poly(methyl methacrylate) (PMMA) oligomer as a base material. The coated fabrics were exposed to various doses of accelerated electrons generated from the 1.5 MeV (25 kW) electron beam accelerator machine. In order to find the suitable conditions that afford the highest performance of pigment printing, the effect of irradiation dose and formulation composition on the color strength of the printed fabrics was investigated. The durability of the printed fabrics in terms of color fastness, tensile mechanical, crease resistance and water absorption was also studied. The results of pigment printing by electron beam irradiation was compared with the conventional thermal printing method with the same pigment colors involving the use of pastes containing binder and thickener systems. It was found that cotton fabrics printed with the pigment colors under the effect of electron beam irradiation displayed higher color strength than those fabrics printed by the conventional thermal fixation at equal pigment color ratios. In this regard, the color strength on cotton fabrics printed with the Imperon violet, blue and yellow pigment colors was 85.2, 75.4 and 91.3 in the case of printing with electron beam and 63.5, 46.0 and 50.2 in the case of thermal curing, respectively. The results showed that the pigment printing by electron beam or thermal curing improves the crease recovery and mechanical properties of cotton fabrics and exhibited comparable durability properties in terms of washing, rubbing and handling

  18. PROPERTIES OF ORGANIC COATINGS CONTAINING PIGMENTS WITH SURFACE MODIFIED WITH A LAYER OF ZnFe2O4

    Directory of Open Access Journals (Sweden)

    Kateřina Nechvílová

    2015-11-01

    Full Text Available This work is focussed on the properties of organic coatings containing pigments whose surface was chemically coated with zinc ferrite (ZnFe2O4 layer. Four silicate types with different particle shapes were selected as the cores: diatomite, talc, kaolin and wollastonite. The untreated particles exhibit a barrier effect. The aim of this project was to apply the surface treatment approach with a view to enhancing not only the model paint films’ anticorrosion properties but also their resistance to physico- mechanical tests pursuant to ISO standards (cupping, bending, impact, adhesion. Other parameters examined included: particle size and morphology, density of the modified pigment, oil consumption, pH, conductivity, and electrochemical properties of the paint film. A solvent-based epoxy-ester resin was used as the binder and also served as the reference material. The pigment volume concentration (PVC was 1% and 10%. During the last stage of the experiment, the paint films were exposed to a corrosive environment stimulating seaside conditions or conditions roads treated with rock salt. The accelerated cyclic corrosion test in a neutral salt mist atmosphere was conducted for 864 hours. The results served to ascertain a suitable environment for organic coatings.

  19. Bacterial production of sunscreen pigments increase arid land soil surface temperature

    Science.gov (United States)

    Couradeau, Estelle; Karaoz, Ulas; Lim, HsiaoChien; Nunes da Rocha, Ulisses; Northern, Trent; Brodie, Eoin; Garcia-Pichel, Ferran

    2015-04-01

    Biological Soil Crusts (BSCs) are desert top soils formations built by complex microbial communities and dominated by the filamentous cyanobacterium Microcoleus sp. BSCs cover extensive desert areas where they correspond to millimeters size mantles responsible of soil stability and fertility. Despite their ecological importance, little is known about how these communities will endure climate change. It has been shown in North America that different species of Microcoleus showed distinct temperature preferences and that their continental biogeography may be susceptible to small changes in temperature with unknown consequences for the ecosystem function. Using a combination of physical, biochemical and microbiological analyses to characterize a successional gradient of crust maturity from light to dark BSCs (Moab, Utah) we found that the concentration of scytonemin (a cyanobacterial sunscreen pigment) increased with crust maturity. We also confirmed that scytonemin was by far the major pigment responsible of light absorption in the visible spectrum in BSCs, and is then responsible of the darkening of the BSCs (i.e decrease of albedo) with maturity. We measured the surface temperature and albedo and found, as predicted, a negative linear relationship between these two parameters. The decrease in albedo across the gradient of crust maturity corresponded to an increase in surface temperature up to 10° C. Upon investigation of microbial community composition using SSU rRNA gene analysis, we demonstrate that warmer crust surface temperatures (decreased albedo) are associated with a replacement of the dominant cyanobacterium; the thermosensitive Microcoleus sp. being replaced by a thermotolerant Microcoleus sp. in darker BSCs. This study supports at the local scale a finding previously made at the continental scale, but also sheds light on the importance of scytonemin as a significant warmer of soils with important consequences for BSC composition and function. Based on

  20. Surface-enhanced Raman spectroscopy studies of yellow organic dyestuffs and lake pigments in oil paint.

    Science.gov (United States)

    Mayhew, Hannah E; Fabian, David M; Svoboda, Shelley A; Wustholz, Kristin L

    2013-08-21

    Identifying natural, organic dyes and pigments is important for the conservation, preservation, and historical interpretation of works of art. Although previous SERS studies have demonstrated high sensitivity and selectivity for red lake pigments using various pretreatment conditions, corresponding investigations of yellow lake pigments and paints are relatively sparse. Here, surface-enhanced Raman scattering (SERS) spectroscopy is used to identify a variety of yellow organic dyestuffs and lake pigments in oil paint. High-quality SERS spectra of yellow dyestuffs (i.e., turmeric, old fustic, Buckthorn berries) and corresponding paints could be obtained with or without sample pretreatment using microliter quantities of HCl and methanol at room temperature. However, the SERS spectra of yellow lake pigments (i.e., Stil de Grain, Reseda lake) and their corresponding oil paints were only observed upon sample pretreatment. Ultimately, we demonstrate a reliable sample treatment protocol for SERS-based identification of turmeric, old fustic, Buckthorn berries, Stil de Grain, and Reseda lake as well as for microscopic samples of the corresponding oil paints.

  1. Applying photoacoustics to quantification of melanin concentration in retinal pigment epithelium (Conference Presentation)

    Science.gov (United States)

    Shu, Xiao; Zhang, Hao F.; Liu, Wenzhong

    2016-03-01

    The melanin in the retinal pigment epithelium (RPE) protects retina and other ocular tissues by photo-screening and acting as antioxidant and free radical scavenger. It helps maintain normal visual functions since human eye is subjected to lifelong high oxygen stress and photon exposure. Loss of the RPE melanin weakens the protection mechanism and jeopardizes ocular health. Local decrease in the RPE melanin concentration is believed to be both a cause and a sign of early-stage age-related macular degeneration (AMD), the leading blinding disease in developed world. Current technology cannot quantitatively measure the RPE melanin concentration which might be a promising marker in early AMD screening. Photoacoustic ophthalmoscopy (PAOM), as an emerging optical absorption-based imaging technology, can potentially be applied to measure the RPE melanin concentration if the dependence of the detectable photoacoustic (PA) signal amplitudes on the RPE melanin concentrations is verified. In this study, we tested the feasibility of using PA signal ratio from RPE melanin and the nearby retinal blood vessels as an indicator of the RPE melanin variation. A novel whole eye optical model was designed and Monte Carlo modeling of light (MCML) was employed. We examined the influences on quantification from PAOM axial resolution, the depth and diameter of the retinal blood vessel, and the RPE thickness. The results show that the scheme is robust to individual histological and illumination variations. This study suggests that PAOM is capable of quantitatively measuring the RPE melanin concentration in vivo.

  2. Temporal and spatial variability of phytoplankton pigment concentrations in the Indian Ocean, derived from the CZCS time series images

    Directory of Open Access Journals (Sweden)

    2005-01-01

    Full Text Available A total of 93 monthly global composite remotely sensed ocean color images from the Coastal Zone Color Scanner (CZCS on board the Nimbus-7 satellite were extracted for the Indian Ocean region (35ºN–55ºS; 30–120ºE to examine the seasonal variations in phytoplankton pigment concentrations, resulting from large-scale changes in physical oceanographic processes. The CZCS data sets were analyzed with the PC-SEAPAK software, and revealed large phytoplankton blooms in the northwest Arabian Sea and off the Somali coast. The blooms were triggered by wind-driven upwelling during the southwest monsoonal months of August and September. In the northern Arabian Sea, phytoplankton blooms, detected from January to March, appeared to be associated with nutrient enhancement resulting from winter convective mixing. In the Bay of Bengal, higher pigment concentrations were confined to the coastal regions but varied only marginally between seasons both in the coastal and offshore regions. Phytoplankton pigment concentrations were consistently low in the open Indian Ocean. Analysis of pigment concentrations extracted from the monthly-accumulated images revealed that the Arabian Sea sustained a greater biomass of phytoplankton compared with any other region of the Indian Ocean. Overall, the coastal regions of the Indian Ocean are richer in phytoplankton pigment than the open Indian Ocean. The number of images in individual areas was highly variable throughout the region due to varying cloud cover.

  3. Electrochromic coatings made of surface modified rutile and anatase pigments: Influence of trisilanol POSS dispersant on electrochromic effect

    International Nuclear Information System (INIS)

    Mihelčič, Mohor; Francetič, Vojmir; Pori, Pavli; Gradišar, Helena; Kovač, Janez; Orel, Boris

    2014-01-01

    Graphical abstract: - Highlights: • Transparent pigmented coatings were deposited from titania dispersions. • Trisilanol POSS was used as dispersant. • Surface modification of pigment particles was established from TEM, TG and IR. • IR spectra studies revealed covalent and H-bond dispersant/pigment interactions. • Electrochromic properties of titanina pigment coatings were shown and discussed. - Abstract: Polyhedral oligomeric silsesqioxanes (POSS) compounds consisting of [RSiO 3/2 ] n groups organized in the form of various polyhedra (T n , n = 3, 6, 8, 10, 12, ….) have not often been used as pigment surface modifiers. Their interactions with pigments are not known in detail and coatings deposited from pigments modified by POSS dispersants are rare. Identification of interactions between a dispersant and the surface of pigments is important from the point of view of obtaining stable pigment dispersions enabling the deposition of optical coatings with high pigment loading, low haze and mechanical integrity. Thin TiO 2 (anatase) pigment coatings (70–260 nm) were deposited from pigment dispersions prepared by milling metatitanic acid (mTiA) powder agglomerates with trisilanol heptaisobutyl silsesquioxane dispersant (trisilanol POSS) in butanol and hexane. The results of TEM, EDAX and TG measurements confirmed the influence of trisilanol POSS dispersant on the formation of a dispersion with a uniform distribution of mTiA and rutile (mTiR) nanoparticles with a size of about 30 ± 5.0 nm and 90 ± 5.0 nm, respectively, as determined from dynamic light scattering (DLS) measurements. The mTiA/trisilanol POSS dispersions with added titanium tetraisopropoxide were deposited on fluorine-doped tin oxide (FTO) coated glass (spin-coating) and indium tin oxide coated polymeric substrate (ITO PET) (coil-coating) and thermally treated at 150 °C. UV–vis spectra, AFM and SEM results showed that the pigment coatings exhibited low haze (up to 6%), low surface

  4. High Concentration of Zinc in Sub-retinal Pigment Epithelial Deposits

    International Nuclear Information System (INIS)

    Lengyel, I.; Flinn, J.; Peto, T.; Linkous, D.; Cano, K.; Bird, A.; Lanzirotti, A.; Frederickson, C.; van Kuijk, F.

    2007-01-01

    One of the hallmarks of age-related macular degeneration (AMD), the leading cause of blindness in the elderly in Western societies, is the accumulation of sub-retinal pigment epithelial deposits (sub-RPE deposits), including drusen and basal laminar deposits, in Bruch's membrane (BM). The nature and the underlying mechanisms of this deposit formation are not fully understood. Because we know that zinc contributes to deposit formation in neurodegenerative diseases, we tested the hypothesis that zinc might be involved in deposit formation in AMD. Using zinc specific fluorescent probes and microprobe synchrotron X-ray fluorescence we showed that sub-RPE deposits in post-mortem human tissues contain unexpectedly high concentrations of zinc, including abundant bio-available (ionic and/or loosely protein bound) ions. Zinc accumulation was especially high in the maculae of eyes with AMD. Internal deposit structures are especially enriched in bio-available zinc. Based on the evidence provided here we suggest that zinc plays a role in sub-RPE deposit formation in the aging human eye and possibly also in the development and/or progression of AMD

  5. High Concentration of Zinc in Sub-retinal Pigment Epithelial Deposits

    Energy Technology Data Exchange (ETDEWEB)

    Lengyel,I.; Flinn, J.; Peto, T.; Linkous, D.; Cano, K.; Bird, A.; Lanzirotti, A.; Frederickson, C.; van Kuijk, F.

    2007-01-01

    One of the hallmarks of age-related macular degeneration (AMD), the leading cause of blindness in the elderly in Western societies, is the accumulation of sub-retinal pigment epithelial deposits (sub-RPE deposits), including drusen and basal laminar deposits, in Bruch's membrane (BM). The nature and the underlying mechanisms of this deposit formation are not fully understood. Because we know that zinc contributes to deposit formation in neurodegenerative diseases, we tested the hypothesis that zinc might be involved in deposit formation in AMD. Using zinc specific fluorescent probes and microprobe synchrotron X-ray fluorescence we showed that sub-RPE deposits in post-mortem human tissues contain unexpectedly high concentrations of zinc, including abundant bio-available (ionic and/or loosely protein bound) ions. Zinc accumulation was especially high in the maculae of eyes with AMD. Internal deposit structures are especially enriched in bio-available zinc. Based on the evidence provided here we suggest that zinc plays a role in sub-RPE deposit formation in the aging human eye and possibly also in the development and/or progression of AMD.

  6. Human Pigmentation, Cutaneous Vitamin D Synthesis and Evolution: Variants of Genes (SNPs) Involved in Skin Pigmentation Are Associated with 25(OH)D Serum Concentration.

    Science.gov (United States)

    Rossberg, Willi; Saternus, Roman; Wagenpfeil, Stefan; Kleber, Marcus; März, Winfried; Reichrath, Sandra; Vogt, Thomas; Reichrath, Jörg

    2016-03-01

    Vitamin D deficiency is common and associated with higher risk for and unfavourable outcome of many diseases. Limited data exist on genetic determinants of serum 25(OH)D concentration. In a cohort of the LURIC study (n=2974, median 25(OH)D concentration 15.5 ng/ml), we tested the hypothesis that variants (SNPs, n=244) of several genes (n=15) involved in different aspects of skin pigmentation, including melanosomal biogenesis (ATP7A, DTNBP1, BLOC1S5, PLDN, PMEL), melanosomal transport within melanocytes (RAB27A, MYO5A, MLPH); or various melanocyte signaling pathways (MC1R, MITF, PAX3, SOX10, DKK1, RACK1, CNR1) are predictive of serum 25(OH)D levels. Eleven SNPs located in 6 genes were associated (ppigmentation and vitamin D for human evolution. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  7. The Relationship of Brimonidine Concentration in Vitreous Body to the Free Concentration in Retina/Choroid Following Topical Administration in Pigmented Rabbits.

    Science.gov (United States)

    Shinno, Keisuke; Kurokawa, Kazuya; Kozai, Seiko; Kawamura, Akio; Inada, Katsuhiro; Tokushige, Hideki

    2017-05-01

    Several studies showed that repeated topical administration of brimonidine tartrate ophthalmic solution reached the human vitreous concentration above 2 nM, which is the concentration necessary to activate the α 2 -adrenergic receptor. The purpose of this study was to elucidate the relationship of the brimonidine concentration in the vitreous body to the free concentration in the retina/choroid which is the target site of brimonidine on neuroprotective effect after topical administration. Brimonidine concentrations in the eye tissues of pigmented rabbits were determined following single ocular administration of 0.1% brimonidine tartrate ophthalmic solution at pH 7.3. Binding affinity of brimonidine to melanin and melanin content in the retina/choroid of pigmented rabbits was also examined. The concentration of free brimonidine which did not bind to melanin in the retina/choroid was calculated using the binding parameters to melanin. Topically applied brimonidine rapidly distributed to intraocular tissues. The elimination rate from melanin-containing tissues such as the iris/ciliary body and retina/choroid was slower than the aqueous humor and vitreous body in pigmented rabbits. In both the anterior and posterior retina/choroid, the free brimonidine concentrations were over 100-fold lower than the total concentrations. The concentrations in the vitreous body closely matched to the free concentrations in the posterior retina/choroid. Simulated free concentrations in the posterior retina/choroid were gradually increased when 0.1% solution was instilled twice daily. The present data indicated that the brimonidine concentration in the vitreous body was comparable to the free concentration in the posterior retina/choroid. This suggests that the vitreous concentration can be a surrogate indicator of the free brimonidine concentration in the posterior retina/choroid. From the present findings, it is expected that multiple instillation of brimonidine tartrate ophthalmic

  8. Effect of pesticides on surface ozone concentration

    International Nuclear Information System (INIS)

    Farag, S.A.; Rizk, H.F.S.; Elbahnasawy, R.M.; Meleigy, M.I.

    1992-01-01

    A comparative study through seasonal variation of surface ozone concentration was carried out recently (1991-1992) at a background area free from expected urban pollutants (Shebin ElKom) and industrial and urban areas (Cairo). Surface ozone concentrations in ppb were generally lower in such area compared with urban or industrial areas studied through the comparative seasonal variations. Notable smog values (>100 ppb) of hourly surface ozone concentrations appeared during summer season in this rural area; during this season, some pesticides were sprayed over cotton and other crops fields in near by agricultural areas. The unexpected jump in the values of diurnal concentrations of surface ozone in that area may be due to the photochemical reactions of these organic pesticides in the atmosphere. 1 fig, 3 tab

  9. Concentric joint space narrowing of the hip associated with hemosiderotic synovitis (HS) including pigmented villonodular synovitis (PVNS)

    International Nuclear Information System (INIS)

    Abrahams, T.G.; Pavlov, H.; Bansal, M.; Bullough, P.

    1988-01-01

    Concentric joint space narrowing of the hip is an expected radiographic finding in cases of inflammatory arthritis such as rheumatoid arthritis or sepsis. However, similar joint space narrowing is associated with chronic hemorrhagic conditions that produce hemosiderotic synovitis. Hemosiderotic synovitis results from chronic intraarticular bleeding such as occurs in pigmented villonodular synovitis, generalized bleeding diathesis, synovial hemangioma, and chronic trauma. Five hips in five patients with concentric joint space narrowing not associated with inflammatory arthritis or with hemophilia were reviewed clinically, radiographically, and pathologically. All patients had a hemosiderotic synovitis. The definitive diagnosis of pigmented villonodular synovitis was made pathologically in two cases that demonstrated nodular areas of giant cell proliferation, collagen production, and lipid-laden histiocytes on histologic samples. (orig.)

  10. "Salting-out" concentration of phytoplankton pigment extracts previous to their analysis by HPLC

    Directory of Open Access Journals (Sweden)

    José Luis Garrido

    2014-04-01

    The recoveries of different pigments varied depending on their chemical nature and the degree of enrichment of the extract. Carotenoids and non-polar chlorophylls were recovered above 85 % with 5M saline solutions, while the recovery of acidic clorophylls (c3 and c2 decreased with enrichment factors.

  11. Spectral Sensitivity of Blowfly Photoreceptors : Dependence on Waveguide Effects and Pigment Concentration

    NARCIS (Netherlands)

    Smakman, J.G.J.; Stavenga, D.G.

    1986-01-01

    Spectral and polarization sensitivities of blowfly R1-6 photoreceptor cells were measured by intracellular recordings in cells which differed in visual pigment content. The spectral sensitivity in the visible wavelength range can be quantitatively explained from the absorption spectrum of blowfly

  12. Meta-Analysis of the Detection of Plant Pigment Concentrations Using Hyperspectral Remotely Sensed Data.

    Directory of Open Access Journals (Sweden)

    Jingfeng Huang

    Full Text Available Passive optical hyperspectral remote sensing of plant pigments offers potential for understanding plant ecophysiological processes across a range of spatial scales. Following a number of decades of research in this field, this paper undertakes a systematic meta-analysis of 85 articles to determine whether passive optical hyperspectral remote sensing techniques are sufficiently well developed to quantify individual plant pigments, which operational solutions are available for wider plant science and the areas which now require greater focus. The findings indicate that predictive relationships are strong for all pigments at the leaf scale but these decrease and become more variable across pigment types at the canopy and landscape scales. At leaf scale it is clear that specific sets of optimal wavelengths can be recommended for operational methodologies: total chlorophyll and chlorophyll a quantification is based on reflectance in the green (550-560nm and red edge (680-750nm regions; chlorophyll b on the red, (630-660nm, red edge (670-710nm and the near-infrared (800-810nm; carotenoids on the 500-580nm region; and anthocyanins on the green (550-560nm, red edge (700-710nm and near-infrared (780-790nm. For total chlorophyll the optimal wavelengths are valid across canopy and landscape scales and there is some evidence that the same applies for chlorophyll a.

  13. Preparation of Mg(OH){sub 2} hybrid pigment by direct precipitation and graft onto cellulose fiber via surface-initiated atom transfer radical polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiao, E-mail: wangxiao@dlpu.edu.cn [School of Textile and Materials Engineering, Dalian Polytechnic University, Dalian, Liaoning Province (China); Zhang, Yue; Lv, Lihua; Cui, Yongzhu; Wei, Chunyan [School of Textile and Materials Engineering, Dalian Polytechnic University, Dalian, Liaoning Province (China); Pang, Guibing [School of Mechanical Engineering and Automation, Dalian Polytechnic University, Dalian, Liaoning Province (China)

    2016-02-15

    Graphical abstract: - Highlights: • Adsorbed anionic dye molecules are conducive to preferential growth of (0 0 1) plane of Mg(OH){sub 2} crystal for Mg(OH){sub 2} pigments. • Uniform coverage of nanosized Mg(OH){sub 2} pigments on fiber surface is achieved via surface-initiated ATRP. • About 4 wt% of Mg(OH){sub 2} pigment on fiber surface shortens nearly half of burning time of cellulose. - Abstract: Mg(OH){sub 2} flame retardant hybrid pigment is synthesized through simultaneous solution precipitation and adsorption of anionic dyes (C.I. Acid Red 6). The Mg(OH){sub 2} hybrid pigment bearing vinyl groups after surface silane modification is immobilized onto the surface of bromo end-functional cellulose fiber by atom transfer radical polymerization (ATRP). The morphology and structure of Mg(OH){sub 2} pigments and cellulose fibers grafted with modified pigments are characterized. The thermal properties, flammability and color fastness of cellulose fibers grafted with modified pigments are measured. The results reveal that anionic dye molecules are adsorbed onto Mg(OH){sub 2} crystals and affect the formation of lamella-like Mg(OH){sub 2} crystals. The cellulose fiber grafted with modified Mg(OH){sub 2} hybrid pigment absorbs about four times heat more than original cellulose fiber with about 4% immobilization ratio of pigment, which shortens nearly half of afterflame time and afterglow time.

  14. Spectral determination of concentrations of functionally diverse pigments in increasingly complex arctic tundra canopies.

    Science.gov (United States)

    Boelman, Natalie T; Magney, Troy S; Logan, Barry A; Griffin, Kevin L; Eitel, Jan U H; Greaves, Heather; Prager, Case M; Vierling, Lee A

    2016-09-01

    As the Arctic warms, tundra vegetation is becoming taller and more structurally complex, as tall deciduous shrubs become increasingly dominant. Emerging studies reveal that shrubs exhibit photosynthetic resource partitioning, akin to forests, that may need accounting for in the "big leaf" net ecosystem exchange models. We conducted a lab experiment on sun and shade leaves from S. pulchra shrubs to determine the influence of both constitutive (slowly changing bulk carotenoid and chlorophyll pools) and facultative (rapidly changing xanthophyll cycle) pigment pools on a suite of spectral vegetation indices, to devise a rapid means of estimating within canopy resource partitioning. We found that: (1) the PRI of dark-adapted shade leaves (PRIo) was double that of sun leaves, and that PRIo was sensitive to variation among sun and shade leaves in both xanthophyll cycle pool size (V + A + Z) (r (2) = 0.59) and Chla/b (r (2) = 0.64); (2) A corrected PRI (difference between dark and illuminated leaves, ΔPRI) was more sensitive to variation among sun and shade leaves in changes to the epoxidation state of their xanthophyll cycle pigments (dEPS) (r (2) = 0.78, RMSE = 0.007) compared to the uncorrected PRI of illuminated leaves (PRI) (r (2) = 0.34, RMSE = 0.02); and (3) the SR680 index was correlated with each of (V + A + Z), lutein, bulk carotenoids, (V + A + Z)/(Chla + b), and Chla/b (r (2) range = 0.52-0.69). We suggest that ΔPRI be employed as a proxy for facultative pigment dynamics, and the SR680 for the estimation of constitutive pigment pools. We contribute the first Arctic-specific information on disentangling PRI-pigment relationships, and offer insight into how spectral indices can assess resource partitioning within shrub tundra canopies.

  15. Atmospheric effects in the remote sensing of phytoplankton pigments

    Science.gov (United States)

    Gordon, H. R.; Clark, D. K.

    1980-01-01

    The accuracy with which relevant atmospheric parameters must be estimated to derive photoplankton pigment concentrations of a given accuracy, from measurements of the ocean's apparent spectral radiance at satellite altitudes, is examined. A phytoplankton pigment algorithm is developed which relates the pigment concentration (c) to the three ratios of upwelling radiance just beneath the sea surface which can be formed from wavelengths (lambda) 440, 520 and 550 nm.

  16. Polarized Human Retinal Pigment Epithelium Exhibits Distinct Surface Proteome on Apical and Basal Plasma Membranes.

    Science.gov (United States)

    Khristov, Vladimir; Wan, Qin; Sharma, Ruchi; Lotfi, Mostafa; Maminishkis, Arvydas; Bharti, Kapil

    2018-01-01

    Surface proteins localized on the apical and basal plasma membranes are required for a cell to sense its environment and relay changes in ionic, cytokine, chemokine, and hormone levels to the inside of the cell. In a polarized cell, surface proteins are differentially localized on the apical or the basolateral sides of the cell. The retinal pigment epithelium (RPE) is an example of a polarized cell that performs a variety of functions that are dependent on its polarized state including trafficking of ions, fluid, and metabolites across the RPE monolayer. These functions are absolutely crucial for maintaining the health and integrity of adjacent photoreceptors, the photosensitive cells of the retina. Here we present a series of approaches to identify and validate the polarization state of cultured primary human RPE cells using immunostaining for RPE apical/basolateral markers, polarized cytokine secretion, electrophysiology, fluid transport, phagocytosis, and identification of plasma membrane proteins through cell surface capturing technology. These approaches are currently being used to validate the polarized state and the epithelial phenotype of human induced pluripotent stem (iPS) cell derived RPE cells. This work provides the basis for developing an autologous cell therapy for age-related macular degeneration using patient specific iPS cell derived RPE.

  17. Formation of new stable pigments from condensation reaction between malvidin 3-glucoside and (-)-epicatechin mediated by acetaldehyde: Effect of tartaric acid concentration.

    Science.gov (United States)

    Sun, Baoshan; Barradas, Tania; Leandro, Conceição; Santos, Cláudia; Spranger, Isabel

    2008-09-15

    The objective of this work was to study the effect of tartaric acid concentration on the condensation reaction between malvidin 3-glucoside (Mv-glc) and flavanols mediated by acetaldehyde in the model solution. The model wine solutions were prepared by 12% ethanol in water (v/v) with two different l-tartaric acid concentrations (5g/l and 25g/l, respectively) and at two different pH values (3.2 and 1.7, respectively). Four new pigments were detected in model wine solutions containing Mv-glc, (-)-epicatechin and acetaldehyde. By reverse-phase HPLC-DAD, ESI-MS and MS(n) fragmentation analysis, the four new pigments were tentatively identified as four isomers of hydroxyethyl malvidin-3-glucoside-ethyl-flavanol. The decrease in the concentration of Mv-glc and (-)-epicatechin and the increase in the concentration of the new identified pigments were more pronounced at higher tartaric acid concentration. At pH 1.7, although the two well-recognized ethyl-linked Mv-glc-flavanol isomers were quantitatively the major pigmented products in the reaction solution throughout the assay period, they appeared less stable than the four new pigments. At pH 3.2, the rate of formation of ethyl-linked Mv-glc-flavanol pigments was much slower than at pH 1.7, whereas the four new pigments were quantitatively the predominant pigmented products at the latter stage of the reaction. Copyright © 2008 Elsevier Ltd. All rights reserved.

  18. Photosynthetic pigment concentrations, gas exchange and vegetative growth for selected monocots and dicots treated with two contrasting coal fly ashes

    Energy Technology Data Exchange (ETDEWEB)

    Yunusa, I.A.M.; Burchett, M.D.; Manoharan, V.; DeSilva, D.L.; Eamus, D.; Skilbeck, C.G. [University of Technology Sydney, Sydney, NSW (Australia). Dept. of Environmental Science

    2009-07-15

    There is uncertainty as to the rates of coal fly ash needed for optimum physiological processes and growth. In the current study we tested the hyothesis that photosynthetic pigments concentrations and CO{sub 2} assimilation (A) are more sensitive than dry weights in plants grown on media amended with coal fly ash. We applied the Terrestrial Plant Growth Test (Guideline 208) protocols of the Organization for Economic Cooperation and Development (OECD) to monocots (barley (Hordeum vulgare) and ryegrass (Secale cereale)) and dicots (canola (Brasica napus), radish (Raphanus sativus), field peas (Pisum sativum), and lucerne (Medicago sativa)) on media amended with fly ashes derived from semi-bituminous (gray ash) or lignite (red ash) coals at rates of 0, 2.5, 5.0, 10, or 20 Mg ha(-1). The red ash had higher elemental concentrations and salinity than the gray ash. Fly ash addition had no significant effect on germination by any of the six species. At moderate rates ({<=}10 Mg ha{sup -1}) both ashes increased (P < 0.05) growth rates and concentrations of chlorophylls a and b, but reduced carotenoid concentrations. Addition of either ash increased A in radish and transpiration in barley. Growth rates and final dry weights were reduced for all of the six test species when addition rates exceeded 10 Mg ha{sup -1} for gray ash and 5 Mg ha{sup -1} for red ash. We concluded that plant dry weights, rather than pigment concentrations and/or instantaneous rates of photosynthesis, are more consistent for assessing subsequent growth in plants supplied with fly ash.

  19. Upper ocean variability of the equatorial Indian Ocean and its relation to chlorophyll pigment concentration.

    Digital Repository Service at National Institute of Oceanography (India)

    Narvekar, J.; PrasannaKumar, S.

    Hydrographic data from the upper ocean together with atmospheric data and satellite data are used to understand the variability of upper ocean and its relation to surface chlorophyll in the Equatorial Indian Ocean. The sea surface temperature showed...

  20. Microanalysis of organic pigments and glazes in polychrome works of art by surface-enhanced resonance Raman scattering

    Science.gov (United States)

    Leona, Marco

    2009-01-01

    Scientific studies of works of art are usually limited by severe sampling restrictions. The identification of organic colorants, a class of compounds relevant for attribution and provenance studies, is further complicated by the low concentrations at which these compounds are used and by the interference of the protein-, gum-, or oil-binding media present in pigment and glaze samples. Surface-enhanced resonance Raman scattering (SERRS) was successfully used to identify natural organic colorants in archaeological objects, polychrome sculptures, and paintings from samples smaller than 25 μm in diameter. The key factors in achieving the necessary sensitivity were a highly active stabilized silver colloid, obtained by the reproducible microwave-supported reduction of silver sulfate with glucose and sodium citrate, and a non-extractive hydrolysis sample treatment procedure that maximizes dye adsorption on the colloid. Among the examples presented are the earliest so far found occurrence of madder lake (in a 4,000 years old Egyptian object dating to the Middle Kingdom period), and the earliest known occurrence in Europe of the South Asian dyestuff lac (in the Morgan Madonna, a 12th century polychrome sculpture from Auvergne, France). PMID:19667181

  1. Microanalysis of organic pigments and glazes in polychrome works of art by surface-enhanced resonance Raman scattering.

    Science.gov (United States)

    Leona, Marco

    2009-09-01

    Scientific studies of works of art are usually limited by severe sampling restrictions. The identification of organic colorants, a class of compounds relevant for attribution and provenance studies, is further complicated by the low concentrations at which these compounds are used and by the interference of the protein-, gum-, or oil-binding media present in pigment and glaze samples. Surface-enhanced resonance Raman scattering (SERRS) was successfully used to identify natural organic colorants in archaeological objects, polychrome sculptures, and paintings from samples smaller than 25 microm in diameter. The key factors in achieving the necessary sensitivity were a highly active stabilized silver colloid, obtained by the reproducible microwave-supported reduction of silver sulfate with glucose and sodium citrate, and a non-extractive hydrolysis sample treatment procedure that maximizes dye adsorption on the colloid. Among the examples presented are the earliest so far found occurrence of madder lake (in a 4,000 years old Egyptian object dating to the Middle Kingdom period), and the earliest known occurrence in Europe of the South Asian dyestuff lac (in the Morgan Madonna, a 12th century polychrome sculpture from Auvergne, France).

  2. Markers of lutein and zeaxanthin status in two age groups of men and women: dietary intake, serum concentrations, lipid profile and macular pigment optical density

    Science.gov (United States)

    2014-01-01

    Background & aims Lutein and zeaxanthin accumulate in retina (macular pigment). Their nutritional status can be assessed using dietary or biochemical markers and both have been associated with macular pigment optical density. We proposed to assess dietary and status markers of lutein and zeaxanthin in a group of healthy Spanish volunteers, considering the potential influence of age, gender and serum lipids to investigate the predictors of the macular pigment optical density. Methods Serum lutein and zeaxanthin concentrations, dietary intake and macular pigment optical density were determined in 108 healthy men and women (20–35 and 45–65 years), using high-performance liquid chromatography, 3-day food records and heterochromic flicker photometry, respectively. Mann–Whitney U-test, Spearman correlation coefficient and multivariate regression analysis were used for the statistical study. Results Serum concentrations and dietary intake of lutein plus zeaxanthin (p lutein (ρ = 0.452, p lutein + zeaxanthin (ρ = 0.431, p lutein and zeaxanthin were expressed in relation to serum lipids in older subjects (ρ = 0.262, p = 0.006). Multivariate regression analysis identified age and serum lutein as major predictors of macular pigment optical density (total sample), and a coefficient of determination of 29.7% for the model including lutein + zeaxathin/cholesterol + triglycerides, sex and fruit + vegetables in the older group. Conclusions The establishment of normal/reference ranges for serum lutein and zeaxanthin should consider age ranges and be expressed in relation to lipid concentrations, at least in subjects over 45 years, as this could influence macular pigment optical density. The macular pigment optical density showed age-specific correlations with lutein plus zeaxanthin expressed in relation to serum lipid concentrations as well as with the fruit and vegetable intake. PMID:24889185

  3. Comparison of macular pigment and serum lutein concentration changes between free lutein and lutein esters supplements in Japanese subjects.

    Science.gov (United States)

    Yoshizako, Hiroko; Hara, Katunori; Takai, Yasuyuki; Kaidzu, Sachiko; Obana, Akira; Ohira, Akihiro

    2016-09-01

    To compare changes in macular pigment optical density (MPOD) and serum lutein concentration between free lutein and lutein esters supplements in healthy Japanese individuals. Twenty healthy subjects (age range, 22-47 years) were recruited into this prospective, randomized, doubled-blind comparative study. Individuals were evenly divided into two groups: free lutein group, supplementation with 10 mg of free lutein; or lutein esters group, supplementation with 20 mg of lutein esters equivalent to 10 mg of free lutein. Each participant took either type of oral lutein daily for 3 months. The serum lutein concentrations and MPOD levels were measured at baseline and 3 and 6 months after the start of supplementation. There were no significant differences in the serum lutein concentrations and MPOD levels at baseline between the groups. The increased serum lutein concentration and MPOD levels at 3 months were respectively, 89% and 38% in the free lutein group and 97% and 17% in the lutein esters group. The serum lutein concentrations in both groups and MPOD levels in the free lutein group increased significantly (p lutein concentrations and MPOD levels were seen between the groups. Three months after supplementation ended, the serum lutein concentration decreased; the MPOD remained elevated in both groups. The serum lutein concentrations and MPOD levels increased significantly with either free lutein or lutein esters, and no significant differences were found between the two. Both were considered useful as lutein supplements. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  4. Physicochemical properties of concentrated Martian surface waters

    Science.gov (United States)

    Tosca, Nicholas J.; McLennan, Scott M.; Lamb, Michael P.; Grotzinger, John P.

    2011-05-01

    Understanding the processes controlling chemical sedimentation is an important step in deciphering paleoclimatic conditions from the rock records preserved on both Earth and Mars. Clear evidence for subaqueous sedimentation at Meridiani Planum, widespread saline mineral deposits in the Valles Marineris region, and the possible role of saline waters in forming recent geomorphologic features all underscore the need to understand the physical properties of highly concentrated solutions on Mars in addition to, and as a function of, their distinct chemistry. Using thermodynamic models predicting saline mineral solubility, we generate likely brine compositions ranging from bicarbonate-dominated to sulfate-dominated and predict their saline mineralogy. For each brine composition, we then estimate a number of thermal, transport, and colligative properties using established models that have been developed for highly concentrated multicomponent electrolyte solutions. The available experimental data and theoretical models that allow estimation of these physicochemical properties encompass, for the most part, much of the anticipated variation in chemistry for likely Martian brines. These estimates allow significant progress in building a detailed analysis of physical sedimentation at the ancient Martian surface and allow more accurate predictions of thermal behavior and the diffusive transport of matter through chemically distinct solutions under comparatively nonstandard conditions.

  5. Enhancement of pigment concentrations in Dunaliella tertiolecta as a result of copper toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Lustigman, B.K.

    1986-11-01

    The addition of copper to coastal waters through the disposal of complex effluents has been increasing. Copper is a well known algicide. It binds to the cell membrane, effects permeability mechanisms and attaches to SH groups on vital enzymes. The ability of algae to withstand copper toxicity varies greatly. The green flagellate, Dunaliella tertiolecta has previously been shown to be highly resistant to copper. Its ability to withstand high concentrations of copper promotes growth of Dunaliella in coastal waters contaminated with increased copper concentrations. Dunaliella tertiolecta possesses chlorophylls a and b, small amounts of alpha- and greater amounts of beta-carotene as well as neoxanthin, zeaxanthin and lutein. This study was undertaken to determine the effect of lethal and sublethal concentrations of copper on the growth and production of chlorophyll and carotenoids in Dunaliella tertiolecta.

  6. Changes in Macular Pigment Optical Density and Serum Lutein Concentration in Japanese Subjects Taking Two Different Lutein Supplements.

    Science.gov (United States)

    Obana, Akira; Tanito, Masaki; Gohto, Yuko; Okazaki, Shigetoshi; Gellermann, Werner; Bernstein, Paul S

    2015-01-01

    To investigate macular pigment optical density (MPOD) and serum concentration changes of lutein in Japanese subjects participating in a clinical trial in which two formulations of lutein and zeaxanthin supplements with different physiochemical properties are used. Thirty-six healthy volunteers were recruited into this prospective, randomized, parallel-group, double-masked comparative study at a single institute. Two products were used, FloraGLO® (Kemin Japan) and XanMax® (Katra Phytochem). The lutein particle size and zeaxanthin concentrations differed between the formulations. The subjects consumed one of the two supplements for a duration of up to 6 months. MPOD levels were measured by resonance Raman spectrometry at baseline and once a month until the end of the study. Serum lutein concentration was measured at baseline, month 3, and month 6. The subjects were also tested for contrast sensitivity, glare sensitivity, visual acuity, and in addition had a focal electroretinogram measured. The mean serum lutein concentrations increased significantly after the first three months, but the mean MPOD levels in either supplement group did not show any statistically significant increase. A detailed analysis, however, revealed three response patterns in both groups for the increase of MPOD levels and serum lutein concentration, i.e. "retinal responders", who had an increase of both MPOD levels and serum lutein concentrations (n = 13), "retinal non-responders", who had only increased serum concentrations and no change in MPOD levels (n = 20), and "retinal and serum non-responders", who had neither MPOD level nor plasma concentration increases (n = 3). The subjects with low MPOD levels at baseline appeared to show increased MPOD levels at the 6 month time point upon lutein supplementation (r = -0.4090, p = 0.0133). Glare sensitivity improved in retinal responders in both supplement groups, while there were no remarkable changes in contrast sensitivity. No statistically

  7. Changes in Macular Pigment Optical Density and Serum Lutein Concentration in Japanese Subjects Taking Two Different Lutein Supplements.

    Directory of Open Access Journals (Sweden)

    Akira Obana

    Full Text Available To investigate macular pigment optical density (MPOD and serum concentration changes of lutein in Japanese subjects participating in a clinical trial in which two formulations of lutein and zeaxanthin supplements with different physiochemical properties are used.Thirty-six healthy volunteers were recruited into this prospective, randomized, parallel-group, double-masked comparative study at a single institute. Two products were used, FloraGLO® (Kemin Japan and XanMax® (Katra Phytochem. The lutein particle size and zeaxanthin concentrations differed between the formulations. The subjects consumed one of the two supplements for a duration of up to 6 months. MPOD levels were measured by resonance Raman spectrometry at baseline and once a month until the end of the study. Serum lutein concentration was measured at baseline, month 3, and month 6. The subjects were also tested for contrast sensitivity, glare sensitivity, visual acuity, and in addition had a focal electroretinogram measured.The mean serum lutein concentrations increased significantly after the first three months, but the mean MPOD levels in either supplement group did not show any statistically significant increase. A detailed analysis, however, revealed three response patterns in both groups for the increase of MPOD levels and serum lutein concentration, i.e. "retinal responders", who had an increase of both MPOD levels and serum lutein concentrations (n = 13, "retinal non-responders", who had only increased serum concentrations and no change in MPOD levels (n = 20, and "retinal and serum non-responders", who had neither MPOD level nor plasma concentration increases (n = 3. The subjects with low MPOD levels at baseline appeared to show increased MPOD levels at the 6 month time point upon lutein supplementation (r = -0.4090, p = 0.0133. Glare sensitivity improved in retinal responders in both supplement groups, while there were no remarkable changes in contrast sensitivity

  8. Effect of mycorrhizal fungi and phosphorus fertilizer on concentration of leaf nutrients and photosynthetic pigments of common bean (Phaseolus vulgaris L. under salinity stress condition

    Directory of Open Access Journals (Sweden)

    B. Parsa-Motlagh

    2016-05-01

    Full Text Available In order to investigate the effect of Mycorrhizal fungi and phosphorus fertilizer on concentration of leaf nutrients and photosynthetic pigments of bean (Phaseolus vulgaris L. in condition of irrigation with saline water, an experiment was conducted based on completely randomized design with three replications in greenhouse of Bahonar University of Kerman, Iran during 2010. The studied factors were water salinity (500 (control, 2000, 4000 and 6000 s.cm-1, phosphorus fertilizer (0, 100 and 200 mg.kg-1 soil in form of Triple super phosphate and mycorrhizal fungi with three levels (GLOMUS MOSSEAE AND GLOMUS INTRARADICES AND no fungi (control. The results showed that the concentrations of chlorophyll a, chlorophyll b, total chlorophyll, carotenoeids, K, Ca and P were decreased with increasing of salinity levels. But salinity increased the concentration of Na and Na/K ratio. Mycorrhizal fungi had no significant effect on concentration of Ca and chlorophyll a. The interaction of salinity and phosphorus fertilizer on concentration of chlorophyll b, Na and P was significant. Results demonstrated that GLOMUS INTRARADICES had better effect on improvement of photosynthetic pigments concentration and concentration of nutrition elements. In low levels of salinity stress, use of MYCORRHIZAL FUNGI WITH PHOSPHORUS FERTILIZER, can reduce the negative effects of salt by increasing of concentration of photosynthetic pigments and nutrition elements.

  9. Consumption of 2 and 4 egg yolks/d for 5 wk increases macular pigment concentrations in older adults with low macular pigment taking cholesterol-lowering statins.

    Science.gov (United States)

    Vishwanathan, Rohini; Goodrow-Kotyla, Elizabeth F; Wooten, Billy R; Wilson, Thomas A; Nicolosi, Robert J

    2009-11-01

    Lutein and zeaxanthin may reduce the risk of dry, age-related macular degeneration because of their photo-oxidative role as macular pigment. The present study evaluated serum lutein, zeaxanthin, and macular pigment optical density (MPOD) responses at 0.25 degrees , 0.5 degrees , and 1 degree retinal eccentricities to the consumption of 2 and 4 egg yolks/d by older adults taking cholesterol-lowering medications. Subjects consumed foods containing 2 followed by 4 egg yolks/d for 5 wk each with a 4-wk egg-free period at baseline and between the 2 interventions. Changes in MPOD (n = 37) with egg yolk consumption were inversely associated (P egg yolks at the 3 retinal eccentricities. MPOD increased by 31% (P = 0.059) at 0.5 degrees with 2 egg yolks. Serum lutein increased by only 16% and 24% (P egg yolks, respectively. Serum HDL cholesterol increased by 5% (P egg yolks. Serum LDL cholesterol did not change with either egg yolk treatment. Consumption of 4 egg yolks/d, and possibly of 2 egg yolks/d, for 5 wk benefited macular health in older adults with low MPOD. Serum HDL cholesterol increased without an increase in LDL cholesterol in this study population, most of whom were taking cholesterol-lowering statins.

  10. Genetic variation and control of chloroplast pigment concentrations in Picea rubens, Picea mariana and their hybrids. I. Ambient and elevated [CO2] environments

    International Nuclear Information System (INIS)

    Major, J.E.; Barsi, D.C.; Mosseler, A.; Campbell, M.

    2007-01-01

    A significant decline has been noted in the red spruce component of the Acadian forest region in eastern Canada and the northeastern United States as a result of excessive harvesting, acid rain, and global warming. Two experiments were performed to acquire benchmark adaptive traits for information from a red spruce (RS) (Picea rubens Sargand) and black spruce (BS) (P. mariana (Mill.) B.S.P.) genetic complex grown in ambient carbon dioxide concentration ([CO 2 ]). The first experiment involved RS-BS seed sources from across the RS geographical range, while the second experiment involved an intra- and interspecific controlled-cross experiment to determine if RS and BS have unique chloroplast pigment concentrations and traits that reflect adaptations to different ecological niches. The objective was to determine species origin and hybrid variations in chloroplast pigment concentrations; examine the effect of elevated [CO 2 ] on chloroplast pigments; determine the inheritance of chloroplast pigments and examine the relationship of chloroplast pigment concentrations of trees grown at ambient [CO 2 ] with productivity traits and nitrogen concentrations. The traits related to light-energy processing have pronounced ecological implications for plant health. Results from the species origin experiment showed that total chlorophyll concentration was about 15 per cent higher in ambient [CO 2 ] than in elevated [CO 2 ]. In ambient [CO 2 ], BS populations had 11 per cent higher total chlorophyll and carotenoid concentrations than RS populations. Results from the controlled-cross experiment showed that families with a hybrid index of 25 per cent RS had the highest total chlorophyll concentrations, and families with hybrid indices of 75 and 100 had the lowest amounts. A predominant male effect for chlorophyll concentration was noted. In ambient and elevated [CO 2 ] environments, crosses with BS males had 10.6 and 17.6 per cent higher total chlorophyll concentrations than crosses

  11. Effect of different CO2 concentrations on biomass, pigment content, and lipid production of the marine diatom Thalassiosira pseudonana.

    Science.gov (United States)

    Sabia, Alessandra; Clavero, Esther; Pancaldi, Simonetta; Salvadó Rovira, Joan

    2018-02-01

    The marine diatom Thalassiosira pseudonana grown under air (0.04% CO 2 ) and 1 and 5% CO 2 concentrations was evaluated to determine its potential for CO 2 mitigation coupled with biodiesel production. Results indicated that the diatom cultures grown at 1 and 5% CO 2 showed higher growth rates (1.14 and 1.29 div day -1 , respectively) and biomass productivities (44 and 48 mg AFDW L -1  day -1 ) than air grown cultures (with 1.13 div day -1 and 26 mg AFDW L -1  day -1 ). The increase of CO 2 resulted in higher cell volume and pigment content per cell of T. pseudonana. Interestingly, lipid content doubled when air was enriched with 1-5% CO 2 . Moreover, the analysis of the fatty acid composition of T. pseudonana revealed the predominance of monounsaturated acids (palmitoleic-16:1 and oleic-18:1) and a decrease of the saturated myristic acid-14:0 and polyunsaturated fatty acids under high CO 2 levels. These results suggested that T. pseudonana seems to be an ideal candidate for biodiesel production using flue gases.

  12. Raman and infrared study of synthetic Maya pigments as a function of heating time and dye concentration

    Science.gov (United States)

    Reza, Layra; Manciu, Felicia; Polette, Lori; Torres, Brenda; Chianelli, Russell

    2007-03-01

    Maya Blue is a famous indigo-based pigment produced by the ancient Mayas. Samples for the present work are made by a synthetic route, and demonstrate similar chemical stability as the ancient Maya Blue samples. Since no direct proof exists that the indigo chemically binds to the inorganic palygorskite lattice, there is still controversy on the resting place of the indigo molecules; i.e. are they in the channels of palygorskite, on the surface, or both. Our analysis by FT-Raman and FT-IR spectroscopy proves the partial elimination of the selection rules for the centrosymmetric indigo, and shows the disappearance of the indigo N-H bonding, as the organic molecules incorporate into palygorskite material. Infrared data confirm the loss of zeolitic water and a partial removal of structural water after the heating process. Evidence of bonding between cationic aluminum and indigo through nitrogen is revealed by FT-Raman measurements. The oxygen carbonyl is also believed to interact with the metal.

  13. Functional Characterization and Signaling Systems of Corazonin and Red Pigment Concentrating Hormone in the Green Shore Crab, Carcinus maenas

    Directory of Open Access Journals (Sweden)

    Jodi L. Alexander

    2018-01-01

    Full Text Available Neuropeptides play a central role as neurotransmitters, neuromodulators and hormones in orchestrating arthropod physiology. The post-genomic surge in identified neuropeptides and their putative receptors has not been matched by functional characterization of ligand-receptor pairs. Indeed, until very recently no G protein-coupled receptors (GPCRs had been functionally defined in any crustacean. Here we explore the structurally-related, functionally-diverse gonadotropin-releasing hormone paralogs, corazonin (CRZ and red-pigment concentrating hormone (RPCH and their G-protein coupled receptors (GPCRs in the crab, Carcinus maenas. Using aequorin luminescence to measure in vitro Ca2+ mobilization we demonstrated receptor-ligand pairings of CRZ and RPCH. CRZR-activated cell signaling in a dose-dependent manner (EC50 0.75 nM and comparative studies with insect CRZ peptides suggest that the C-terminus of this peptide is important in receptor-ligand interaction. RPCH interacted with RPCHR with extremely high sensitivity (EC50 20 pM. Neither receptor bound GnRH, nor the AKH/CRZ-related peptide. Transcript distributions of both receptors indicate that CRZR expression was, unexpectedly, restricted to the Y-organs (YO. Application of CRZ peptide to YO had no effect on ecdysteroid biosynthesis, excepting a modest stimulation in early post-molt. CRZ had no effect on heart activity, blood glucose levels, lipid mobilization or pigment distribution in chromatophores, a scenario that reflected the distribution of its mRNA. Apart from the well-known activity of RPCH as a chromatophorotropin, it also indirectly elicited hyperglycemia (which was eyestalk-dependent. RPCHR mRNA was also expressed in the ovary, indicating possible roles in reproduction. The anatomy of CRZ and RPCH neurons in the nervous system is described in detail by immunohistochemistry and in situ hybridization. Each peptide has extensive but non-overlapping distribution in the CNS, and neuroanatomy

  14. Controlled surface morphology and hydrophilicity of polycaprolactone toward human retinal pigment epithelium cells

    International Nuclear Information System (INIS)

    Shahmoradi, Saleheh; Yazdian, Fatemeh; Tabandeh, Fatemeh; Soheili, Zahra-Soheila; Hatamian Zarami, Ashraf Sadat; Navaei-Nigjeh, Mona

    2017-01-01

    Applying scaffolds as a bed to enhance cell proliferation and even differentiation is one of the treatment of retina diseases such as age-related macular degeneration (AMD) which deteriorating photoreceptors and finally happening blindness. In this study, aligned polycaprolactone (PCL) nanofibers were electrospun and at different conditions and their characteristics were measured by scanning electron microscope (SEM) and contact angle. Response surface methodology (RSM) was used to optimize the diameter of fabricated nanofibers. Two factors as solution concentration and voltage value were considered as independent variables and their effects on nanofibers' diameters were evaluated by central composite design and the optimum conditions were obtained as 0.12 g/mL and 20 kV, respectively. In order to decrease the hydrophobicity of PCL, the surface of the fabricated scaffolds was modified by alkaline hydrolysis method. Contact time of the scaffolds and alkaline solution and concentration of alkaline solution were optimized using Box Behnken design and (120 min and 5 M were the optimal, respectively). Contact angle measurement showed the high hydrophilicity of treated scaffolds (with contact angle 7.48°). Plasma surface treatment was applied to compare the effect of using two kinds of surface modification methods simultaneously on hydrolyzed scaffolds. The RPE cells grown on scaffolds were examined by immunocytochemistry (ICC), MTT and continuous inspection of cellular morphology. Interestingly, Human RPE cells revealed their characteristic morphology on hydrolyzed scaffold well. As a result, we introduced a culture substrate with low diameter (185.8 nm), high porosity (82%) and suitable hydrophilicity (with contact angle 7.48 degree) which can be promising for hRPE cell transplantation. - Highlights: • Dimethylformamide (DMF) has significant effect on reduction of fibers' diameter. • Having high hydrophilicity by alkaline hydrolysis • Suitable

  15. Design and optimization of nanoparticle-pigmented solar selective absorber coatings for high-temperature concentrating solar thermal systems

    Science.gov (United States)

    Wang, Xiaoxin; Yu, Xiaobai; Fu, Sidan; Lee, Eldred; Kekalo, Katerina; Liu, Jifeng

    2018-01-01

    We present a systematic approach for the design and optimization of nanoparticle-pigmented solar selective absorbers for operation at 750 °C. Using the scattering and absorption cross-sections calculated by Lorenz-Mie scattering theory as input, we employ a four-flux radiative transfer method to investigate the solar selectivity mechanism and optimize the optical-to-thermal conversion efficiency (ηtherm) as a function of the metallic nanoparticle material, the nanoparticle diameter, the volume fraction, and the coating thickness. Among the nanoparticle material candidates in this study, C54-TiSi2 is the best option with an optimized ηtherm = 87.0% for a solar concentration ratio of C = 100 and ηtherm = 94.4% for C = 1000 at 750 °C. NiSi is also a promising candidate comparable to TiSi2 in thermal efficiency. Experimentally, an un-optimized 200 nm-diameter TiSi2 nanoparticle-silicone solar selective coating has already achieved ηtherm = 89.8% for C = 1000 at 750 °C. This performance is consistent with the theoretical model and close to the thermal efficiency of the commercial Pyromark 2500 coatings (90.1%). We also demonstrate that Ni/NiSi core-shell structures embedded in the SiO1.5 matrix is thermally stable at 750 °C for 1000 h in air. These results indicate that silicide cermet coatings are promising to achieve high optical performance and high temperature thermal stability simultaneously.

  16. Monitoring of pigmented and wooden surfaces in accelerated ageing processes by FT-Raman spectroscopy and multivariate control charts.

    Science.gov (United States)

    Marengo, Emilio; Robotti, Elisa; Liparota, Maria Cristina; Gennaro, Maria Carla

    2004-07-08

    Two of the most suitable analytical techniques used in the field of cultural heritage are NIR (near-infrared) and Raman spectroscopy. FT-Raman spectroscopy coupled to multivariate control charts is applied here for the development of a new method for monitoring the conservation state of pigmented and wooden surfaces. These materials were exposed to different accelerated ageing processes in order to evaluate the effect of the applied treatments on the goods surfaces. In this work, a new approach based on the principles of statistical process control (SPC) to the monitoring of cultural heritage, has been developed: the conservation state of samples simulating works-of-art has been treated like an industrial process, monitored with multivariate control charts, owing to the complexity of the spectroscopic data collected. The Raman spectra were analysed by principal component analysis (PCA) and the relevant principal components (PCs) were used for constructing multivariate Shewhart and cumulative sum (CUSUM) control charts. These tools were successfully applied for the identification of the presence of relevant modifications occurring on the surfaces. CUSUM charts however proved to be more effective in the identification of the exact beginning of the applied treatment. In the case of wooden boards, where a sufficient number of PCs were available, simultaneous scores monitoring and residuals tracking (SMART) charts were also investigated. The exposure to a basic attack and to high temperatures produced deep changes on the wooden samples, clearly identified by the multivariate Shewhart, CUSUM and SMART charts. A change on the pigment surface was detected after exposure to an acidic solution and to the UV light, while no effect was identified on the painted surface after the exposure to natural atmospheric events.

  17. The Effect of Pigment Volume Concentration on Film Formation and the Mechanical Properties of Coatings Based on Water-Dispersion Paint and Varnish Materials

    Science.gov (United States)

    Kasyanenko, I. M.; Kramarenko, V. Yu.

    2018-01-01

    The effect of pigment volume concentration (PVC) on the film formation process and properties of coatings based on the water dispersion of an Acronal 290D styrene-acrylate copolymer and a pigment/filler system used for paint materials in construction was investigated. An analysis of the results obtained is performed within the framework of the concept of the critical PVC. It is shown that the initiation and development of internal stresses occurs the faster, the higher the PVC, but the position of the maximum or the inflection point of the internal stress-drying time curve complies with a universal value of the solid volume content in the compositions. It is found that the internal stresses and Young's modulus of coatings are characterized by an extreme concentration relation that, for the reduced elastic modulus, can be described by a system of equations based on the Halpin-Tsai equation.

  18. Surface micro-distributions of pigment and the relation between smearing and local mass distribution

    International Nuclear Information System (INIS)

    Buelow, K.; Kristiansson, P.; Larsson, T.; Malmberg, S.; Elfman, M.; Malmqvist, K.; Pallon, J.; Shariff, A.

    2001-01-01

    In this work, the process of smearing and its time evolution have been investigated. When smearing occurs, the print is removed from the printed paper and colours other parts of the paper or the printing press and destroys the final product. To study the re-distribution of ink, cyan ink with Cu as a tracer in the coloured pigment has been used. Non-printed paper has been pressed against the paper, 1 and 5 s after the printing. The micro-distributions of ink on both printed and non-printed papers have then been studied using particle-induced X-ray emission (PIXE). Basis weight was measured with the off-axis scanning transmission ion microscopy (STIM) technique and this data was correlated with the data from the print. One conclusion is that the process of smearing is not dependent on the shape of the pigment distribution, i.e. copper, or the content of copper in a specific pixel. On the contrary, the smearing was found to be related to the structure of the paper and that it mainly occurs where the paper is thicker

  19. Influence of temperature and dopant concentration on structural, morphological and optical properties of nanometric Ce1-xErxO2-δ (x = 0.05–0.20) as a pigment

    KAUST Repository

    Stojmenović, Marija

    2015-07-31

    Ceramic pigments based on cerium oxide were synthesized by self–propagating room temperature method and their color properties were assessed from the viewpoint of potential environmentally nontoxic pink pigments. Thermal stabilities of the pigments were examined at 600, 900 and 1200 ºC. According to X–ray powder diffraction and Raman spectroscopy results, all obtained pigments were single–phase solid solutions of cerium oxide, independent of the concentration of dopants. The X–ray analysis showed that the crystallites were of nanometric dimensions, as recorded and by transmission electron microscopy analysis. Color characteristics of solid solutions, which depended on concentracion erbium ions and calcination temperature, and their position in the chromaticity diagram were studied by ultraviolet–visible spectrophotometry, which confirmed potential application of environmentally friendly pigments of desired color. The color efficiency of pigments was also evaluated by colorimetric analysis.

  20. The Effect of Modified Eggs and an Egg-Yolk Based Beverage on Serum Lutein and Zeaxanthin Concentrations and Macular Pigment Optical Density: Results from a Randomized Trial

    Science.gov (United States)

    Kelly, Elton R.; Plat, Jogchum; Haenen, Guido R. M. M.; Kijlstra, Aize; Berendschot, Tos T. J. M.

    2014-01-01

    Increasing evidence suggests a beneficial effect of lutein and zeaxanthin on the progression of age-related macular degeneration. The aim of this study was to investigate the effect of lutein or zeaxanthin enriched eggs or a lutein enriched egg-yolk based buttermilk beverage on serum lutein and zeaxanthin concentrations and macular pigment levels. Naturally enriched eggs were made by increasing the levels of the xanthophylls lutein and zeaxanthin in the feed given to laying hens. One hundred healthy volunteers were recruited and randomized into 5 groups for 90 days. Group one added one normal egg to their daily diet and group two received a lutein enriched egg-yolk based beverage. Group three added one lutein enriched egg and group four one zeaxanthin enriched egg to their diet. Group five was the control group and individuals in this group did not modify their daily diet. Serum lutein and zeaxanthin concentrations and macular pigment densities were obtained at baseline, day 45 and day 90. Macular pigment density was measured by heterochromatic flicker photometry. Serum lutein concentration in the lutein enriched egg and egg yolk-based beverage groups increased significantly (plutein or zeaxanthin enriched egg yolks as well as an egg yolk-based beverage show increases in serum lutein and zeaxanthin levels that are comparable with a daily use of 5 mg supplements. Trial Registration ClinicalTrials.gov NCT00527553 PMID:24675775

  1. Production of Monascus pigments as extracellular crystals by cell suspension culture.

    Science.gov (United States)

    Lu, Fengling; Liu, Lujie; Huang, Yaolin; Zhang, Xuehong; Wang, Zhilong

    2018-01-01

    It is generally accepted that Monascus pigments are predominantly cell-bound, including both intracellular and surface-bound pigments. This long-term misconception was corrected in the present work. Production of extracellular crystal pigments by submerged culture of Monascus sp. was confirmed by microscopic observation and collection of Monascus pigments from extracellular broth by direct membrane filtration. Following up the new fact, the bioactivity of mycelia as whole-cell biocatalyst for biosynthesis and biodegradation of Monascus pigments had been detailedly examined in both an aqueous solution and a nonionic surfactant micelle aqueous solution. Based on those experimental results, cell suspension culture in an aqueous medium was developed as a novel strategy for accumulation of high concentration of Monascus pigments. Thus, glucose feeding during submerged culture in the aqueous medium was carried out successfully and high orange Monascus pigments concentration of near 4 g/L was achieved.

  2. Surface sampling concentration and reaction probe

    Science.gov (United States)

    Van Berkel, Gary J; Elnaggar, Mariam S

    2013-07-16

    A method of analyzing a chemical composition of a specimen is described. The method can include providing a probe comprising an outer capillary tube and an inner capillary tube disposed co-axially within the outer capillary tube, where the inner and outer capillary tubes define a solvent capillary and a sampling capillary in fluid communication with one another at a distal end of the probe; contacting a target site on a surface of a specimen with a solvent in fluid communication with the probe; maintaining a plug volume proximate a solvent-specimen interface, wherein the plug volume is in fluid communication with the probe; draining plug sampling fluid from the plug volume through the sampling capillary; and analyzing a chemical composition of the plug sampling fluid with an analytical instrument. A system for performing the method is also described.

  3. Removal of high concentration of sulfate from pigment industry effluent by chemical precipitation using barium chloride: RSM and ANN modeling approach.

    Science.gov (United States)

    Navamani Kartic, D; Aditya Narayana, B Ch; Arivazhagan, M

    2018-01-15

    Sulfate ions pose a major threat and challenge in the treatment of industrial effluents. The sample of wastewater obtained from a pigment industry contained large quantities of sulfate in the form of sodium sulfate which resulted in high TDS. As the removal of sulfate from pigment industry effluent was not reported previously, this work was focused on removing the sulfate ions from the effluent by chemical precipitation using barium chloride. The efficiency of sulfate removal was nearly 100% at an excess dosage of barium chloride, which precipitates the dissolved sulfate ions in the form of barium sulfate. Optimization of the parameters was done using Response Surface Methodology (RSM). This work is the first attempt for modeling the removal of sulfate from pigment industry effluent using RSM and Artificial Neural Network (ANN). Prediction by both the models was evaluated and both of them exhibited good performance (R 2 value > 0.99). It was observed that the prediction by RSM (R 2 value 0.9986) was closer to the experimental results than ANN prediction (R 2 value 0.9955). The influence on the pH and conductivity of the solution by dosage of precipitant was also studied. The formation of barium sulfate was confirmed by characterization of the precipitate. Therefore, the sulfate removed from the effluent was converted into a commercially valuable precipitate. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Use of zinc-rich primers co-pigmented with phosphates applied on rusty steel surfaces contaminated with soluble salts

    Directory of Open Access Journals (Sweden)

    de la Fuente, D.

    2003-12-01

    Full Text Available Zinc-rich primers (ZRP offer good anti-corrosive behaviour, and are an ecologically acceptable solution, when applied on carbon steel substrates that are rusted and contaminated with soluble salts (chlorides and sulphates, provided certain critical contamination thresholds are not exceeded. The use of phosphate-type co-pigments in ZRP formulations, could lead to an increase in tolerable critical levels for soluble salts. This work discusses the results of a comparative study carried out with ZRP and non-ZRP systems incorporating various types of co-pigments in several concentrations, applied on substrates contaminated with different chloride and sulphate levels. The study considers the results of atmospheric exposure test (24 months in Madrid atmosphere and of accelerated humidity condensation tests.

    Las imprimaciones ricas en zinc (IRZ ofrecen un buen comportamiento, además de ser una solución ecológicamente aceptable, cuando se aplican sobre substratos de acero al carbono herrumbrado y contaminado con sales solubles (cloruros y sulfatos, siempre que no se superen ciertos umbrales críticos de contaminación. El empleo en la formulación de las IRZ de copigmentos de tipo fosfato podría suponer un aumento en los niveles críticos tolerables de sales solubles. En el presente trabajo se discuten los resultados del estudio comparativo llevado a cabo con sistemas IRZ y no IRZ con diferentes tipos de estos copigmentos en varias proporciones, aplicados sobre substratos contaminados con distintos niveles de cloruros y sulfatos. El estudio incluye los resultados tanto del ensayo de exposición atmosférica (24 meses en la atmósfera de Madrid como el ensayo acelerado de condensación de humedad.

  5. Natural variability in the surface ocean carbonate ion concentration

    OpenAIRE

    N. S. Lovenduski; M. C. Long; K. Lindsay

    2015-01-01

    We investigate variability in the surface ocean carbonate ion concentration ([CO32−]) on the basis of a long control simulation with a fully-coupled Earth System Model. The simulation is run with a prescribed, pre-industrial atmospheric CO2 concentration for 1000 years, permitting investigation of natural [CO32−] variability on interannual to multi-decadal timescales. We find high interannual variability in surface [CO32−] in the tropical...

  6. Natural variability in the surface ocean carbonate ion concentration

    OpenAIRE

    Lovenduski, N. S.; Long, M. C.; Lindsay, K.

    2015-01-01

    We investigate variability in the surface ocean carbonate ion concentration ([CO32−]) on the basis of a~long control simulation with an Earth System Model. The simulation is run with a prescribed, pre-industrial atmospheric CO2 concentration for 1000 years, permitting investigation of natural [CO32−] variability on interannual to multi-decadal timescales. We find high interannual variability in surface [CO32−] in the tropical Pacific and ...

  7. A non invasive method to detect stratigraphy, thicknesses and pigment concentration of pictorial multilayers based on EDXRF and vis-RS: in situ applications

    International Nuclear Information System (INIS)

    Bonizzoni, L.; Caglio, S.; Galli, A.; Poldi, G.

    2008-01-01

    Energy dispersive XRF analysis (EDXRF) in association with visible reflectance spectroscopy (vis-RS), both achieved by portable instruments, can be successfully applied, in a wide range of cases, to investigate wood or canvas paintings in order to obtain some stratigraphic information with non-invasive techniques. The specific aim of this work is to use them as quantitative tools: EDXRF to reconstruct the thicknesses of the detected layers, vis-RS to report pigment concentration in the uppermost layer. We present here some in situ analyses of famous paintings by Andrea Mantegna and Giovanni Bellini, compared with stratigraphic optical microscopy observations on cross sections. Advantages and limits are pointed out. (orig.)

  8. Estimation of surface area concentration of workplace incidental nanoparticles based on number and mass concentrations

    Science.gov (United States)

    Park, J. Y.; Ramachandran, G.; Raynor, P. C.; Kim, S. W.

    2011-10-01

    Surface area was estimated by three different methods using number and/or mass concentrations obtained from either two or three instruments that are commonly used in the field. The estimated surface area concentrations were compared with reference surface area concentrations (SAREF) calculated from the particle size distributions obtained from a scanning mobility particle sizer and an optical particle counter (OPC). The first estimation method (SAPSD) used particle size distribution measured by a condensation particle counter (CPC) and an OPC. The second method (SAINV1) used an inversion routine based on PM1.0, PM2.5, and number concentrations to reconstruct assumed lognormal size distributions by minimizing the difference between measurements and calculated values. The third method (SAINV2) utilized a simpler inversion method that used PM1.0 and number concentrations to construct a lognormal size distribution with an assumed value of geometric standard deviation. All estimated surface area concentrations were calculated from the reconstructed size distributions. These methods were evaluated using particle measurements obtained in a restaurant, an aluminum die-casting factory, and a diesel engine laboratory. SAPSD was 0.7-1.8 times higher and SAINV1 and SAINV2 were 2.2-8 times higher than SAREF in the restaurant and diesel engine laboratory. In the die casting facility, all estimated surface area concentrations were lower than SAREF. However, the estimated surface area concentration using all three methods had qualitatively similar exposure trends and rankings to those using SAREF within a workplace. This study suggests that surface area concentration estimation based on particle size distribution (SAPSD) is a more accurate and convenient method to estimate surface area concentrations than estimation methods using inversion routines and may be feasible to use for classifying exposure groups and identifying exposure trends.

  9. Estimation of surface area concentration of workplace incidental nanoparticles based on number and mass concentrations

    International Nuclear Information System (INIS)

    Park, J. Y.; Ramachandran, G.; Raynor, P. C.; Kim, S. W.

    2011-01-01

    Surface area was estimated by three different methods using number and/or mass concentrations obtained from either two or three instruments that are commonly used in the field. The estimated surface area concentrations were compared with reference surface area concentrations (SA REF ) calculated from the particle size distributions obtained from a scanning mobility particle sizer and an optical particle counter (OPC). The first estimation method (SA PSD ) used particle size distribution measured by a condensation particle counter (CPC) and an OPC. The second method (SA INV1 ) used an inversion routine based on PM1.0, PM2.5, and number concentrations to reconstruct assumed lognormal size distributions by minimizing the difference between measurements and calculated values. The third method (SA INV2 ) utilized a simpler inversion method that used PM1.0 and number concentrations to construct a lognormal size distribution with an assumed value of geometric standard deviation. All estimated surface area concentrations were calculated from the reconstructed size distributions. These methods were evaluated using particle measurements obtained in a restaurant, an aluminum die-casting factory, and a diesel engine laboratory. SA PSD was 0.7–1.8 times higher and SA INV1 and SA INV2 were 2.2–8 times higher than SA REF in the restaurant and diesel engine laboratory. In the die casting facility, all estimated surface area concentrations were lower than SA REF . However, the estimated surface area concentration using all three methods had qualitatively similar exposure trends and rankings to those using SA REF within a workplace. This study suggests that surface area concentration estimation based on particle size distribution (SA PSD ) is a more accurate and convenient method to estimate surface area concentrations than estimation methods using inversion routines and may be feasible to use for classifying exposure groups and identifying exposure trends.

  10. Pickering emulsions stabilized by coloured organic pigment particles.

    Science.gov (United States)

    Binks, Bernard P; Olusanya, Samuel O

    2017-01-01

    The possibility of stabilizing emulsions of water and non-polar alkane with pure, coloured organic pigment particles is explored. Seven pigment types each possessing a primary colour of the rainbow were selected. Their solubility in water or heptane was determined using a spectrophotometric method and their surface energies were derived from the contact angles of probe liquids on compressed disks of the particles. As expected, most of the pigments are relatively hydrophobic but pigment orange is quite hydrophilic. At equal volumes of oil and water, preferred emulsions were water-in-oil (w/o) for six pigment types and oil-in-water (o/w) for pigment orange. The emulsion type is in line with calculated contact angles of the particles at the oil-water interface being either side of 90°. Their stability to coalescence increases with particle concentration. Emulsions are shown to undergo limited coalescence from which the coverage of drop interfaces by particles has been determined. In a few cases, close-packed primary particles are visible around emulsion droplets. At constant particle concentration, the influence of the volume fraction of water ( φ w ) on emulsions was also studied. For the most hydrophilic pigment orange, emulsions are o/w at all φ w , whereas they are w/o for the most hydrophobic pigments (red, yellow, green and blue). For pigments of intermediate hydrophobicity however (indigo and violet), catastrophic phase inversion becomes possible with emulsions inverting from w/o to o/w upon increasing φ w . For the first time, we link the pigment surface energy to the propensity of emulsions to phase invert transitionally or catastrophically.

  11. Pigment patterns in the Arabian Sea: Spatio-temporal variability as observed by ADEOS

    Digital Repository Service at National Institute of Oceanography (India)

    Jadhav, N.A.; Rao, L.V.G.; Panigrahy, R.C.

    The spatial and temporal variations of the near-surface concentration of phytoplankton pigment observed by ADEOS during November 1996 - May 1997 are studied in relation to SST and winds. Monthly composite images from OCTS depict spatial and temporal...

  12. Inadvertent polychlorinated biphenyls in commercial paint pigments.

    Science.gov (United States)

    Hu, Dingfei; Hornbuckle, Keri C

    2010-04-15

    A polychlorinated biphenyl (PCB) that was not produced as part of the Aroclor mixtures banned in the 1980s was recently reported in air samples collected in Chicago, Philadelphia, the Arctic, and several sites around the Great Lakes. In Chicago, the congener 3,3'-dichlorobiphenyl or PCB11 was found to be the fifth most concentrated congener and ubiquitous throughout the city. The congener exhibited strong seasonal concentration trends that suggest volatilization of this compound from common outdoor surfaces. Due to these findings and also the compound's presence in waters that received waste from paint manufacturing facilities, we hypothesized that PCB11 may be present in current commercial paint. In this study we measured PCBs in paint sold on the current retail market. We tested 33 commercial paint pigments purchased from three local paint stores. The pigment samples were analyzed for all 209 PCB congeners using gas chromatography with tandem mass spectrometry (GC-MS/MS). More than 50 PCB congeners including several dioxin-like PCBs were detected, and the PCB profiles varied due to different types of pigments and different manufacturing processes. PCB congeners were detected in azo and phthalocyanine pigments which are commonly used in paint but also in inks, textiles, paper, cosmetics, leather, plastics, food and other materials. Our findings suggest several possible mechanisms for the inadvertent production of specific PCB congeners during the manufacturing of paint pigments.

  13. Efficiency of a concentric matrix track detector surface scanning

    International Nuclear Information System (INIS)

    Bek-Uzarov, Dj.; Nikezic, D.; Kostic, D.; Krstic, D.; Cuknic, O.

    1995-01-01

    Heavy particle ionizing radiation track counting on the surface of a solid state round surface detector is made using the microscope and scanning step by step by a round field of vision. The whole solid state detector surface could not be fully or completely covered by round fields of visions. Therefore detector surface could be divided on the two parts, the larger surface, being under fields of vision, really scanned and no scanned missed or omitted surface. The ratio between omitted and scanned surfaces is so called track scanning efficiency. The knowledge of really counted, or scanned surface is a important value for evaluating the real surface track density an exposed solid state track detector. In the paper a matrix of a concentric field of vision made around the first microscope field of vision placed in center of the round disc of the scanned track detector is proposed. In a such scanning matrix the real scanned surface could be easy calculated and by the microscope scanning made as well. By this way scanned surface is very precisely obtained as well. Precise knowledge of scanned and omitted surface allows to obtain more precise scanning efficiency factor as well as real surface track density, the main parameter in solid state track detection measurements. (author)

  14. Variations of surface ozone concentration across the Klang Valley, Malaysia

    Science.gov (United States)

    Latif, Mohd Talib; Huey, Lim Shun; Juneng, Liew

    2012-12-01

    Hourly air quality data covering the period 2004-2008 was obtained from the Air Quality Division, the Department of Environment (DOE) through long-term monitoring by Alam Sekitar Sdn. Bhd. (ASMA) were analysed to investigate the variations of surface ozone (O3) in the Klang Valley, Malaysia. A total of nine monitoring stations were selected for analysis in this study and the results show that there are distinct seasonal patterns in the surface O3 across the Klang Valley. A high surface O3 concentration is usually observed between January and April, while a low surface O3 concentration is found between June and August. Analysis of daily variations in surface O3 and the precursors - NO, NO2, CO, NMHC and UVb, indicate that the surface O3 photochemistry in this study area exhibits a positive response to the intensity and wavelength in UVb while being influenced by the concentration of NOx, particularly through tritration processes. Although results from our study suggested that NMHCs may influence the maximum O3 concentration, further investigation is required. Wind direction during different monsoons was found to influence the concentration of O3 around the Klang Valley. HYSPLIT back trajectories (-72 h) were used to indicate the air-mass transport patterns on days with high concentrations of surface O3 in the study area. Results show that 47% of the high O3 days was associated with the localized circulation. The remaining 32% and 22% were associated with mid-range and long-range transport across the South China Sea from the northeast.

  15. Effects of dissolved oxygen concentration on photosynthetic bacteria wastewater treatment: Pollutants removal, cell growth and pigments production.

    Science.gov (United States)

    Meng, Fan; Yang, Anqi; Zhang, Guangming; Wang, Hangyao

    2017-10-01

    Dissolved oxygen (DO) is an important parameter in photosynthetic bacteria (PSB) wastewater treatment. This study set different DO levels and detected the pollutants removal, PSB growth and pigments production. Results showed that DO significantly influenced the performances of PSB wastewater treatment process. The highest COD (93%) and NH 3 -N removal (83%) was achieved under DO of 4-8mg/L, but DO of 2-4mg/L was recommended considering the aeration cost. PSB biomass reached 1645mg/L under DO of 4-8mg/L with satisfying co-enzyme Q10 content. The biomass yield was relatively stable at all DO levels. For bacteriochlorophyll and carotenoids, DO>1mg/L could satisfy their production. On the other hand, DOpigments production occurred at 24h; biomass reached peak at 48h; and the optimal time for pollutants removal was 72h. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Optimisation of ultrasound-assisted extraction of natural pigment from annatto seeds by response surface methodology (RSM).

    Science.gov (United States)

    Yolmeh, Mahmoud; Habibi Najafi, Mohammad B; Farhoosh, Reza

    2014-07-15

    The present study reports on the extraction of natural pigment from annatto seeds. Response surface methodology (RSM) was used to investigate the effect of process variables on the ultrasound-assisted extraction (UAE). Four independent variables including temperature (20-80°C), sonication time (2-10 min), duty cycle (0.2-0.8s) and the ratio of seeds to the solvent (5-20%) were studied. According to the results, the optimal UAE condition was obtained with a temperature of 72.7°C, extraction time of 7.25 min, the ratio of seed to solvent of 14% and duty cycle of 0.8s. At these conditions, extraction yield determined as 6.35% and the absorbance value as 0.865%. The experimental values under optimal condition were in good consistent with the predicted values, which suggested UAE is more efficient process as compared to conventional extraction. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Concentration polarization, surface currents, and bulk advection in a microchannel

    DEFF Research Database (Denmark)

    Nielsen, Christoffer Peder; Bruus, Henrik

    2014-01-01

    We present a comprehensive analysis of salt transport and overlimiting currents in a microchannel during concentration polarization. We have carried out full numerical simulations of the coupled Poisson-Nernst-Planck-Stokes problem governing the transport and rationalized the behavior of the syst...... as in the limit of negligible surface charge. By including the effects of diffusion and advection in the diffuse part of the electric double layers, we extend a recently published analytical model of overlimiting current due to surface conduction....

  18. Retrieve Aerosol Concentration Based On Surface Model and Distribution of Concentration of PM2.5

    Science.gov (United States)

    Cui, Hongzhi

    2017-04-01

    As China's economy continues to grow, urbanization continues to advance, along with growth in all areas to pollutant emissions in the air industry, air quality also continued to deteriorate. Aerosol concentrations as a measure of air quality of the most important part of are more and more people's attention. Traditional monitoring stations measuring aerosol concentration method is accurate, but time-consuming and can't be done simultaneously measure a large area, can only rely on data from several monitoring sites to predict the concentration of the panorama. Remote Sensing Technology retrieves aerosol concentrations being by virtue of their efficient, fast advantages gradually into sight. In this paper, by the method of surface model to start with the physical processes of atmospheric transport, innovative aerosol concentration coefficient proposed to replace the traditional aerosol concentrations, pushed to a set of retrieval of aerosol concentration coefficient method, enabling fast and efficient Get accurate air pollution target area. At the same paper also monitoring data for PM2.5 in Beijing were analyzed from different angles, from the perspective of the data summarized in Beijing PM2.5 concentration of time, space, geographical distribution and concentration of PM2.5 and explored the relationship between aerosol concentration coefficient and concentration of PM2.5. Key words,Air Pollution, Aerosol concentration , PM2.5 , Retrieve

  19. A Val85Met Mutation in Melanocortin-1 Receptor Is Associated with Reductions in Eumelanic Pigmentation and Cell Surface Expression in Domestic Rock Pigeons (Columba livia)

    Science.gov (United States)

    Guernsey, Michael W.; Ritscher, Lars; Miller, Matthew A.; Smith, Daniel A.; Schöneberg, Torsten; Shapiro, Michael D.

    2013-01-01

    Variation in the melanocortin-1 receptor (Mc1r) is associated with pigmentation diversity in wild and domesticated populations of vertebrates, including several species of birds. Among domestic bird species, pigmentation variation in the rock pigeon ( Columba livia ) is particularly diverse. To determine the potential contribution of Mc1r variants to pigment diversity in pigeons, we sequenced Mc1r in a wide range of pigeon breeds and identified several single nucleotide polymorphisms, including a variant that codes for an amino acid substitution (Val85Met). In contrast to the association between Val85Met and eumelanism in other avian species, this change was associated with pheomelanism in pigeons. In vitro cAMP accumulation and protein expression assays revealed that Val85Met leads to decreased receptor function and reduced cell surface expression of the mutant protein. The reduced in vitro function is consistent with the observed association with reduced eumelanic pigmentation. Comparative genetic and cellular studies provide important insights about the range of mechanisms underlying diversity among vertebrates, including different phenotypic associations with similar mutations in different species. PMID:23977400

  20. A Val85Met mutation in melanocortin-1 receptor is associated with reductions in eumelanic pigmentation and cell surface expression in domestic rock pigeons (Columba livia.

    Directory of Open Access Journals (Sweden)

    Michael W Guernsey

    Full Text Available Variation in the melanocortin-1 receptor (Mc1r is associated with pigmentation diversity in wild and domesticated populations of vertebrates, including several species of birds. Among domestic bird species, pigmentation variation in the rock pigeon (Columbalivia is particularly diverse. To determine the potential contribution of Mc1r variants to pigment diversity in pigeons, we sequenced Mc1r in a wide range of pigeon breeds and identified several single nucleotide polymorphisms, including a variant that codes for an amino acid substitution (Val85Met. In contrast to the association between Val85Met and eumelanism in other avian species, this change was associated with pheomelanism in pigeons. In vitro cAMP accumulation and protein expression assays revealed that Val85Met leads to decreased receptor function and reduced cell surface expression of the mutant protein. The reduced in vitro function is consistent with the observed association with reduced eumelanic pigmentation. Comparative genetic and cellular studies provide important insights about the range of mechanisms underlying diversity among vertebrates, including different phenotypic associations with similar mutations in different species.

  1. Multilayer perceptron neural network-based approach for modeling phycocyanin pigment concentrations: case study from lower Charles River buoy, USA.

    Science.gov (United States)

    Heddam, Salim

    2016-09-01

    This paper proposes multilayer perceptron neural network (MLPNN) to predict phycocyanin (PC) pigment using water quality variables as predictor. In the proposed model, four water quality variables that are water temperature, dissolved oxygen, pH, and specific conductance were selected as the inputs for the MLPNN model, and the PC as the output. To demonstrate the capability and the usefulness of the MLPNN model, a total of 15,849 data measured at 15-min (15 min) intervals of time are used for the development of the model. The data are collected at the lower Charles River buoy, and available from the US Environmental Protection Agency (USEPA). For comparison purposes, a multiple linear regression (MLR) model that was frequently used for predicting water quality variables in previous studies is also built. The performances of the models are evaluated using a set of widely used statistical indices. The performance of the MLPNN and MLR models is compared with the measured data. The obtained results show that (i) the all proposed MLPNN models are more accurate than the MLR models and (ii) the results obtained are very promising and encouraging for the development of phycocyanin-predictive models.

  2. Nonphotosynthetic Pigments as Potential Biosignatures

    Science.gov (United States)

    Cockell, Charles S.; Meadows, Victoria S.

    2015-01-01

    Abstract Previous work on possible surface reflectance biosignatures for Earth-like planets has typically focused on analogues to spectral features produced by photosynthetic organisms on Earth, such as the vegetation red edge. Although oxygenic photosynthesis, facilitated by pigments evolved to capture photons, is the dominant metabolism on our planet, pigmentation has evolved for multiple purposes to adapt organisms to their environment. We present an interdisciplinary study of the diversity and detectability of nonphotosynthetic pigments as biosignatures, which includes a description of environments that host nonphotosynthetic biologically pigmented surfaces, and a lab-based experimental analysis of the spectral and broadband color diversity of pigmented organisms on Earth. We test the utility of broadband color to distinguish between Earth-like planets with significant coverage of nonphotosynthetic pigments and those with photosynthetic or nonbiological surfaces, using both 1-D and 3-D spectral models. We demonstrate that, given sufficient surface coverage, nonphotosynthetic pigments could significantly impact the disk-averaged spectrum of a planet. However, we find that due to the possible diversity of organisms and environments, and the confounding effects of the atmosphere and clouds, determination of substantial coverage by biologically produced pigments would be difficult with broadband colors alone and would likely require spectrally resolved data. Key Words: Biosignatures—Exoplanets—Halophiles—Pigmentation—Reflectance spectroscopy—Spectral models. Astrobiology 15, 341–361. PMID:25941875

  3. Satellite constraints on surface concentrations of particulate matter

    Science.gov (United States)

    Ford Hotmann, Bonne

    Because of the increasing evidence of the widespread adverse effects on human health from exposure to poor air quality and the recommendations of the World Health Organization to significantly reduce PM2.5 in order to reduce these risks, better estimates of surface air quality globally are required. However, surface measurements useful for monitoring particulate exposure are scarce, especially in developing countries which often experience the worst air pollution. Therefore, other methods are necessary to augment estimates in regions with limited surface observations. The prospect of using satellite observations to infer surface air quality is attractive; however, it requires knowledge of the complicated relationship between satellite-observed aerosol optical depth (AOD) and surface concentrations. This dissertation explores how satellite observations can be used in conjunction with a chemical transport model (GEOS-Chem) to better understand this relationship. First, we investigate the seasonality in aerosols over the Southeastern United States using observations from several satellite instruments (MODIS, MISR, CALIOP) and surface network sites (IMPROVE, SEARCH, AERONET). We find that the strong summertime enhancement in satellite-observed aerosol optical depth (factor 2-3 enhancement over wintertime AOD) is not present in surface mass concentrations (25-55% summertime enhancement). Goldstein et al. [2009] previously attributed this seasonality in AOD to biogenic organic aerosol; however, surface observations show that organic aerosol only accounts for ~35% of PM2.5 mass and exhibits similar seasonality to total surface PM2.5. The GEOS-Chem model generally reproduces these surface aerosol measurements, but under represents the AOD seasonality observed by satellites. We show that seasonal differences in water uptake cannot sufficiently explain the magnitude of AOD increase. As CALIOP profiles indicate the presence of additional aerosol in the lower troposphere

  4. Concentration of involatile salts at evaporating water surfaces

    International Nuclear Information System (INIS)

    Gardner, G.C.

    1988-02-01

    Safety cases for the PWR often need to know how much of the soluble salts in the water will evaporate with the steam during flashing and when the steam is discharged to the atmosphere. Some ideal evaporating systems to give guidance. Simple formulae are derived for the surface concentration relative to the bulk concentration. An analysis is also presented which derives a formula for the mass transfer process in the steam due to both diffusion and convection, which arises from the evaporation process. The convection process will usually dominate. (author)

  5. Surface processing and ageing behavior of silk fabrics treated with atmospheric-pressure plasma for pigment-based ink-jet printing

    Science.gov (United States)

    Zhang, Chunming; Wang, Libing; Yu, Miao; Qu, Lijun; Men, Yajing; Zhang, Xiangwu

    2018-03-01

    Pigment inkjet printing has highlighted the advantages of cost-effective, short production cycle and environment-friendly. However, patterns directly printed with pigment inks usually have low color yields and blurry images which are caused by bleeding phenomenon. This work presents an atmospheric-pressure plasma method for improving the pigment-based ink-jet printing performance of silk fabrics. The effects of surface changes induced are discussed, with data derived from morphological study by atomic force microscopy (AFM), chemical analysis using X-ray photoelectron spectroscopy (XPS) and contact angle measurement. Ink-jet printing experiments were conducted to study the influence of measured changes on anti-bleeding property and color strength of treated and original samples. The ageing experiment indicates that the modified silk fabrics should be printed within 24 h after plasma processing for maximum color yields. This study explores an effective approach for the atmospheric-pressure plasma, which can provide its significant use in improving the surface properties and ink-jet printing performance of fabrics.

  6. Lead concentrations and risk exposure assessment in surface soils ...

    African Journals Online (AJOL)

    This study investigated lead concentrations in < 250 μm and < 75 μm of deposited dust and< 2000 μm, < 250 μm, and < 75 μm of surface soils at undeveloped residential lands leased to auto-mechanic artisans for a minimum of ten years and estimated exposure risk for children that will reside on the polluted lands after the ...

  7. Influence of water pollution on the growth and pigment concentration of the microalgae Phaeodactylum tricornutum Bohlin (Bacillariophyta).

    Science.gov (United States)

    Zhuravel, Elena V; Markina, Zhanna V; Aizdaicher, Nina A

    2012-05-01

    The aim of the work was to study the influence of the water taken from one of the most polluted parts of the Peter the Great Bay (the Japan Sea), the Nakhodka Bay, on the growth and chlorophyll a concentration in the cells of microalga P. tricornutum Bohlin (Bacillariophyta). The estimation of the dynamics of cell number growth and chlorophyll a concentration in the cells of microalga grown in the water from the Nakhodka Bay was made. At the same time, in 2007-2008, the main hydrochemical parameters, such as water salinity, dissolved oxygen concentration, BOD(5), organic and mineral phosphates concentration, anionic surfactants, and total petroleum hydrocarbons, were determined. It is shown that in July 2007, when most hydrochemical parameters were lower than the maximum permissible level, the culture growth and chlorophyll a contents in the cells did not differ from the control for certain. In other seasons these indices differed greatly from the control. The positive correlation between the concentration of dissolved oxygen, phosphates, petroleum hydrocarbons, and the number of microalga cells, grown in the water from the Nakhodka Bay, was shown.

  8. Natural variability in the surface ocean carbonate ion concentration

    Directory of Open Access Journals (Sweden)

    N. S. Lovenduski

    2015-11-01

    Full Text Available We investigate variability in the surface ocean carbonate ion concentration ([CO32−] on the basis of a~long control simulation with an Earth System Model. The simulation is run with a prescribed, pre-industrial atmospheric CO2 concentration for 1000 years, permitting investigation of natural [CO32−] variability on interannual to multi-decadal timescales. We find high interannual variability in surface [CO32−] in the tropical Pacific and at the boundaries between the subtropical and subpolar gyres in the Northern Hemisphere, and relatively low interannual variability in the centers of the subtropical gyres and in the Southern Ocean. Statistical analysis of modeled [CO32−] variance and autocorrelation suggests that significant anthropogenic trends in the saturation state of aragonite (Ωaragonite are already or nearly detectable at the sustained, open-ocean time series sites, whereas several decades of observations are required to detect anthropogenic trends in Ωaragonite in the tropical Pacific, North Pacific, and North Atlantic. The detection timescale for anthropogenic trends in pH is shorter than that for Ωaragonite, due to smaller noise-to-signal ratios and lower autocorrelation in pH. In the tropical Pacific, the leading mode of surface [CO32−] variability is primarily driven by variations in the vertical advection of dissolved inorganic carbon (DIC in association with El Niño–Southern Oscillation. In the North Pacific, surface [CO32−] variability is caused by circulation-driven variations in surface DIC and strongly correlated with the Pacific Decadal Oscillation, with peak spectral power at 20–30-year periods. North Atlantic [CO32−] variability is also driven by variations in surface DIC, and exhibits weak correlations with both the North Atlantic Oscillation and the Atlantic Multidecadal Oscillation. As the scientific community seeks to detect the anthropogenic influence on ocean carbonate chemistry, these results

  9. Natural variability in the surface ocean carbonate ion concentration

    Science.gov (United States)

    Lovenduski, N. S.; Long, M. C.; Lindsay, K.

    2015-11-01

    We investigate variability in the surface ocean carbonate ion concentration ([CO32-]) on the basis of a~long control simulation with an Earth System Model. The simulation is run with a prescribed, pre-industrial atmospheric CO2 concentration for 1000 years, permitting investigation of natural [CO32-] variability on interannual to multi-decadal timescales. We find high interannual variability in surface [CO32-] in the tropical Pacific and at the boundaries between the subtropical and subpolar gyres in the Northern Hemisphere, and relatively low interannual variability in the centers of the subtropical gyres and in the Southern Ocean. Statistical analysis of modeled [CO32-] variance and autocorrelation suggests that significant anthropogenic trends in the saturation state of aragonite (Ωaragonite) are already or nearly detectable at the sustained, open-ocean time series sites, whereas several decades of observations are required to detect anthropogenic trends in Ωaragonite in the tropical Pacific, North Pacific, and North Atlantic. The detection timescale for anthropogenic trends in pH is shorter than that for Ωaragonite, due to smaller noise-to-signal ratios and lower autocorrelation in pH. In the tropical Pacific, the leading mode of surface [CO32-] variability is primarily driven by variations in the vertical advection of dissolved inorganic carbon (DIC) in association with El Niño-Southern Oscillation. In the North Pacific, surface [CO32-] variability is caused by circulation-driven variations in surface DIC and strongly correlated with the Pacific Decadal Oscillation, with peak spectral power at 20-30-year periods. North Atlantic [CO32-] variability is also driven by variations in surface DIC, and exhibits weak correlations with both the North Atlantic Oscillation and the Atlantic Multidecadal Oscillation. As the scientific community seeks to detect the anthropogenic influence on ocean carbonate chemistry, these results will aid the interpretation of trends

  10. Changes in ultraviolet-B and visible optical properties and absorbing pigment concentrations in pecan leaves during a growing season

    Science.gov (United States)

    Yadong Qi; Shuju Bai; Gordon M. Heisler

    2003-01-01

    UV-B (280-320 nm) and visible (400-760 nm) spectral reflectance, transmittance, and absorptance; chlorophyll content; UV-B absorbing compound concentration; and leaf thickness were measured for pecan (Carya illinoensis) leaves over a growing season (April-October). Leaf samples were collected monthly from a pecan plantation located on the Southern...

  11. Key factors for UV curable pigment dispersions

    International Nuclear Information System (INIS)

    Magny, B.; Pezron, E.; Ciceron, P.H.; Askienazy, A.

    1999-01-01

    UV oligomers with good pigment dispersion are needed to allow good formulation flexibility and possibility to apply thinner films. Pigment dispersion mainly depends on three phenomena: the wetting of agglomerates, the breakage of agglomerates by mechanical stress and the stabilization of smaller agglomerates and primary particles against flocculation. It has been shown that oligomers with low viscosity and low surface tension induce a good pigment wetting. Examples of monomers and oligomers for good pigment dispersion are given

  12. Diurnal changes in the xanthophyll cycle pigments of freshwater algae correlate with the environmental hydrogen peroxide concentration rather than non-photochemical quenching

    Science.gov (United States)

    Roach, Thomas; Miller, Ramona; Aigner, Siegfried; Kranner, Ilse

    2015-01-01

    Background and Aims In photosynthetic organisms exposure to high light induces the production of reactive oxygen species (ROS), such as hydrogen peroxide (H2O2), which in part is prevented by non-photochemical quenching (NPQ). As one of the most stable and longest-lived ROS, H2O2 is involved in key signalling pathways in development and stress responses, although in excess it can induce damage. A ubiquitous response to high light is the induction of the xanthophyll cycle, but its role in algae is unclear as it is not always associated with NPQ induction. The aim of this study was to reveal how diurnal changes in the level of H2O2 are regulated in a freshwater algal community. Methods A natural freshwater community of algae in a temporary rainwater pool was studied, comprising photosynthetic Euglena species, benthic Navicula diatoms, Chlamydomonas and Chlorella species. Diurnal measurements were made of photosynthetic performance, concentrations of photosynthetic pigments and H2O2. The frequently studied model organisms Chlamydomonas and Chlorella species were isolated to study photosynthesis-related H2O2 responses to high light. Key Results NPQ was shown to prevent H2O2 release in Chlamydomonas and Chlorella species under high light; in addition, dissolved organic carbon excited by UV-B radiation was probably responsible for a part of the H2O2 produced in the water column. Concentrations of H2O2 peaked at 2 µm at midday and algae rapidly scavenged H2O2 rather than releasing it. A vertical H2O2 gradient was observed that was lowest next to diatom-rich benthic algal mats. The diurnal changes in photosynthetic pigments included the violaxanthin and diadinoxanthin cycles; the former was induced prior to the latter, but neither was strictly correlated with NPQ. Conclusions The diurnal cycling of H2O2 was apparently modulated by the organisms in this freshwater algal community. Although the community showed flexibility in its levels of NPQ, the diurnal changes in

  13. ceramic pigment

    Indian Academy of Sciences (India)

    Co costs and environmental impact, most of the current research activities concerning Co-based blue pigments have been focused upon the minimization of the employed amount of Co in their formulation (thus reducing both the economic costs and the toxicity). Accordingly, several studies have been previously reported on ...

  14. Heavy metal concentration of settled surface dust in residential building

    International Nuclear Information System (INIS)

    Nor Aimi abdul Wahab; Fairus Muhamad Darus; Norain Isa; Siti Mariam Sumari; Nur Fatihah Muhamad Hanafi

    2012-01-01

    The concentrations of heavy metals (Cu, Ni, Pb and Zn) in settled surface dust were collected from nine residential buildings in different areas in Seberang Prai Tengah District, Pulau Pinang. The samples of settled surface dust were collected in 1 m 2 area by using a polyethylene brush and placed in the dust pan by sweeping the living room floor most accessible to the occupants. Heavy metals concentrations were determined by using inductively coupled plasma optical emission spectrometer (ICP-OES) after digestion with nitric acid and sulphuric acid. The results show that the range of heavy metals observed in residential buildings at Seberang Prai Tengah were in the range of 2.20-14.00 mg/ kg, 1.50-32.70 mg/ kg, 1.50-76.80 mg/ kg and 14.60-54.40 mg/ kg for Cu, Ni, Pb and Zn respectively. The heavy metal concentration in the investigated areas followed the order: Pb > Zn > Ni > Cu. Statistical analysis indicates significant correlation between all the possible pairs of heavy metal. The results suggest a likely common source for the heavy metal contamination, which could be traced most probably to vehicular emissions, street dust and other related activities. (author)

  15. Averaging of diffusing contaminant concentrations in atmosphere surface layer

    International Nuclear Information System (INIS)

    Ivanov, E.A.; Ramzina, T.V.

    1985-01-01

    Calculations permitting to average concentration fields of diffusing radioactive contaminant coming from the NPP exhaust stack in the atmospheric surface layer are given. Formulae of contaminant concentration field calculation are presented; it depends on the average wind direction value (THETA) for time(T) and stability of this direction (σsub(tgTHETA) or σsub(THETA)). Probability of wind direction deviation from the average value for time T is satisfactory described by the Gauss law. With instability increase in the atmosphere σ increases, when wind velocity increasing the values of σ decreases for all types of temperature gradients. Nonuniformity of σ value dependence on averaging time T is underlined, that requires accurate choice of σsub(tgTHETA) and σsub(THETA) parameters in calculations

  16. The power of pigments, calibrating chemoclines with chlorophylls and carotenoids.

    Science.gov (United States)

    Junium, C. K.; Uveges, B. T.

    2017-12-01

    Phototrophic organisms produce a diversity of pigments that serve a broad range of specific biochemical functions. Pigments are either directly associated with the photosynthetic apparatus, the most notable being chlorophyll a, or are accessory pigments such as the carotenoid lutein. Their functions can also be categorized into roles that are related to light harvesting (e.g. fucoxanthin) or for photoprotection (e.g. scytonemin). The abundances of these two classes of pigments from environmental samples can provide specific information about photointensity and how it relates to environmental changes. For example, a deepening of the chemo/nutricline can result in the increased production of light gathering relative to photoprotective pigments. Here we apply a relatively simple approach that utilizes the abundance of photosynthetic relative to photoprotective pigments to help constrain changes in the water column position of the chemocline. To test the efficacy of this approach we have utilized the sedimentary record of the anoxic Lake Kivu in the East African Rift. Recent Lake Kivu sediments are punctuated by a series of sapropels that may be associated with overturn of the lake, and release of carbon dioxide and sulfide during potential limnic eruptions. Carbon and nitrogen isotopes decrease significantly at the onset of sapropel deposition and suggest that 13C-depleted dissolved inorganic carbon was upwelled into surface waters and was accompanied by high concentrations of ammonium, that allowed for 15N-depletion during incomplete nitrogen utilization. The pigment record, specifically the ratio of the photoprotective carotenoids lutein and zeaxanthin to chlorophyll a increases significantly at the onset of sapropel deposition. This suggests that the chemocline shallowed, displacing phototrophic communities toward the surface of the lake where light intensities required production of photoprotective pigments. This approach can easily be applied to a wide variety of

  17. Estimates of surface methane emissions over Europe using observed surface concentrations and the FLEXPART trajectory model

    Science.gov (United States)

    Weaver, C. J.; Kiemle, C.; Kawa, S. R.; Aalto, T.; Necki, J.; Steinbacher, M.; Arduini, J.; Apadula, F.; Berkhout, H.; Hatakka, J.; O'Doherty, S.

    2013-12-01

    We use surface methane observations from nine European ground stations, and the FLEXPART Lagrangian transport model to obtain surface methane emissions for 2010. Our inversion shows the strongest emissions from the Netherlands and the coal mines in Upper Silesia Poland. This is qualitatively consistent with the EDGAR surface flux inventory. We also report significant surface fluxes from wetlands in southern Finland during July and August and reduced wetland fluxes later in the year. Our simulated methane surface concentration captures at least half of the daily variability in the observations, suggesting that the transport model is correctly simulating the regional transport pathways over Europe. We also use our trajectory model to determine whether future space-based remote sensing instruments (MERLIN) will be able to detect both natural and anthropogenic changes in the surface flux strengths.

  18. Evaluation of shape and size effects on optical properties of ZnO pigment

    International Nuclear Information System (INIS)

    Kiomarsipour, Narges; Shoja Razavi, Reza; Ghani, Kamal; Kioumarsipour, Marjan

    2013-01-01

    The pigment with optimized morphology would attain maximum diffuse solar reflectance at a lower film thickness and reduce the pigment volume concentration required. This factor would contribute to a reduction in overall weight and possibly extend the durability of the system to longer time scales, specially in space assets. In the present work, five different morphologies of ZnO pigment were synthesized by hydrothermal method. The ZnO pigments were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM) and N 2 adsorption (BET). The optical property of the ZnO pigments was investigated by UV/VIS/NIR spectrophotometer. The results indicated that the optical properties of ZnO powders were strongly affected by the particle size and morphology. The nanorods and microrods ZnO structures showed the minimum spectral reflectance in visible and near infrared regions, whereas the novel nanoparticle-decorated ZnO pigment revealed the maximum spectral reflectance in the same regions. The reflectance spectra of scale-like and submicrorods ZnO were in the middle of the others. The higher surface roughness led to higher light scattering in nanoparticle-decorated ZnO pigment and multiple-scattering in them. These results proved that a significant improvement in the scattering efficiency of ZnO pigment can be realized by utilizing an optimized nanoparticle-decorated pigment.

  19. ceramic pigment

    Indian Academy of Sciences (India)

    sintering process). The other samples show practically the same morphology, and the mean particle size of the obtained powders is in agreement with that for inorganic pigments used in most applications (i.e., between 0.1 and 10 μm [13]). 3.3 Optical spectroscopy (powders). Since Co2SiO4 mineral owes its violet colour to ...

  20. Characterization of red pigment concentrating hormone (RPCH) in the female mud crab (Scylla olivacea) and the effect of 5-HT on its expression.

    Science.gov (United States)

    Kornthong, Napamanee; Chotwiwatthanakun, Charoonroj; Chansela, Piyachat; Tinikul, Yotsawan; Cummins, Scott F; Hanna, Peter J; Sobhon, Prasert

    2013-05-01

    Red pigment concentrating hormone (RPCH) is a member of the chromatophorotropic hormones and, in crustaceans, it is synthesized in the eyestalk. We have isolated a full-length cDNA for a RPCH preprohormone gene (Scyol-RPCH) from the eyestalks of female mud crabs, Scylla olivacea. The open reading frame consists of 642 nucleotides, and encodes a deduced 108 amino acid precursor protein, which includes a signal peptide, the RPCH (pQLNFSPGWamide), and an associated peptide. We show that the mud crab RPCH peptide exhibits 100% identity with 15 other decapods. Expression of Scyol-RPCH within adult mud crab takes place in the eyestalk, brain, and ventral nerve cord, comprising subesophageal ganglion, thoracic ganglion, and abdominal ganglion. In situ hybridization demonstrates specific expression within neuronal clusters 1, 2, 3, and 4 of the eyestalk X-organ, clusters 6, 8, 9, 10, and 17 of the brain, and in neuronal clusters of the ventral nerve cord. We found that administration of 5-HT up-regulates RPCH gene expression in the eyestalk, suggesting that RPCH may play a role as a downstream hormone of 5-HT. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. Microanalysis of Organic Pigments in Ancient Textiles by Surface-Enhanced Raman Scattering on Agar Gel Matrices

    Directory of Open Access Journals (Sweden)

    Marilena Ricci

    2016-01-01

    Full Text Available We review some new methods based on surface-enhanced Raman scattering (SERS for the nondestructive/minimally invasive identification of organic colorants in objects whose value or function precludes sampling, such as historic and archeological textiles, paintings, and drawing. We discuss in detail the methodology we developed for the selective extraction and identification of anthraquinones and indigoids in the typical concentration used in textiles by means of an ecocompatible homogeneous nanostructured agar matrix. The extraction system was modulated according to the chemical properties of the target analyte by choosing appropriate reagents for the extraction and optimizing the extraction time. The system has been found to be extremely stable, easy to use and produce, easy to store, and at the same time able to be analyzed even after long time intervals, maintaining its enhancement properties unaltered, without the detriment of the extracted compound. Highly structured SERS band intensities have been obtained from the extracted dyes adopting laser light excitations at 514.5 and 785 nm of a micro-Raman setup. This analytical method has been found to be extremely safe for the analyzed substrates, thus being a promising procedure for the selective analysis and detection of molecules at low concentration in the field of artworks conservation.

  2. Concentrations of sunscreens and antioxidant pigments in Arctic Calanus spp. in relation to ice cover, ultraviolet radiation, and the phytoplankton spring bloom

    DEFF Research Database (Denmark)

    Hylander, Samuel; Kiørboe, Thomas; Snoeijs, Pauline

    2015-01-01

    Arctic zooplankton ascend to shallow depths during spring to graze on the yearly occurring phytoplankton bloom. However, in surface waters they are exposed to detrimental ultraviolet radiation (UVR) levels. Here, we quantified concentrations of substances known to have UVR-protective functions, n...

  3. Lung deposited surface area concentrations in a street canyon

    Science.gov (United States)

    Kuuluvainen, Heino; Hietikko, Riina; Järvinen, Anssi; Saukko, Erkka; Irjala, Matti; Niemi, Jarkko V.; Timonen, Hilkka; Keskinen, Jorma; Rönkkö, Topi

    2017-04-01

    Street canyons are interesting environments with respect to the dispersion of traffic emissions and human exposure. Pedestrians may be exposed to relatively high concentrations of fine particles and the vertical dispersion affects the human exposure above the ground level in buildings. Previously, particle concentrations have been measured in street canyons at a few different heights (Marini et al., 2015). The information on the lung deposited surface area (LDSA) concentration, which is a relevant metric for the negative health effects, is very limited even at the ground level of street canyons (Kuuluvainen et al., 2016). More information especially on the vertical dispersion and the ground level concentrations is needed, for instance, for the use of urban planning and the design of ventilation systems in buildings. Measurements were carried out in a busy street canyon in Helsinki, Finland, at an urban super-site measurement station (Mäkelänkatu 50). The data included vertical concentration profiles measured in an intensive measurement campaign with a Partector (Naneos GmbH) installed into a drone, long-term measurements with an AQ Urban particle sensor (Pegasor Ltd.), and an extensive comparison measurement in the field with different devices measuring the LDSA. These devices were an AQ Urban, Partector, DiSCmini (Testo AG), NSAM (TSI Inc.), and an ELPI+ (Dekati Ltd.). In addition, continuous measurements of gas phase components, particle size distributions, and meteorology were run at the supersite. The vertical profile measurements were con-ducted in November 2016 during two days. In the measurements, the drone was flown from the ground level to an altitude of 50 or 100 m, which is clearly above the roof level of the buildings. Altogether, 48 up-and-down flights were conducted during the two days. The vertical profiles were supported by continuous measurements at the ground level on both sides of the street canyon. The long-term measurements were conducted

  4. CONCENTRATION OF LIQUID PES MEDIA ON THE GROWTH AND PHOTOSYNTHETIC PIGMENTS OF SEAWEEDS COTONII PROPAGULE (KAPPAPHYCUS ALVAREZII DOTY THROUGH TISSUE CULTURE

    Directory of Open Access Journals (Sweden)

    Lumbessy S.Y.

    2018-03-01

    Full Text Available In vitro tissue culture of Kappaphycus alvarezii, the required nutrients are derived from the culture medium. The use of liquid PES medium as a culture medium has been widely applied to increase the growth rate of seaweeds. Seaweeds growth is also associated with photosynthetic pigments. If the absorption of light by chlorophyll a is sufficient, the process of photosynthesis will take place optimally, so that the growth of seaweed can increase. This study aims to examine the effect of liquid PES medium on the growth and photosynthetic pigments of Kappaphycus alvarezii propagule. The treatments used included 10 ml and 20 ml liquid PES media. Parameters measured include weight gain, daily growth rate, photosynthetic pigment contents (chlorophyll a and phycoerythrin and absorption of nitrate (N and phosphorus (P. The results showed that the use of 10 ml liquid PES medium gave better results than the use of 20 ml liquid PES medium on all parameters measured.

  5. Analysis of Indian pigment gallstones

    International Nuclear Information System (INIS)

    Rautray, T.R.; Vijayan, V.; Panigrahi, S.

    2007-01-01

    Particle induced X-ray emission and particle induced γ-ray emission spectroscopic techniques have been carried out to analyse the elemental concentrations of human pigment gallstone samples from eastern region (Orissa) and southern region (Chennai) of India. It was observed that 18 minor/trace elements namely Na, Mg, Al, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br and Pb were present in the pigment gallstone samples of both the regions. Our study reveals that average concentration of all elements except Ni in south Indian pigment gallstone samples is higher than that of corresponding values in east Indian pigment gallstone samples whereas elements like Al, P, S, Cl and V did not show much variation between these two regions. Fourier transform infra-red analysis was carried out to identify the functional groups and the classification of the pigment type gallstones of both the regions. The thermal behaviour of pigment gallstones was carried out by thermogravimetry-derivative thermogravimetry analysis

  6. Drusenoid retinal pigment epithelium detachments

    Directory of Open Access Journals (Sweden)

    Miguel Hage Amaro

    2015-10-01

    Full Text Available ABSTRACT The authors make a review of drusenoid retinal pigment epithelium detachments(DPDs, a form of retinal pigment epithelium detachment(PED that evolves from confluent and large soft drusen.Drusenoidretinal pigment epithelial detachments are a recognized element of the "dry" AMD. Until now, no treatment is indicated in drusenoid PEDs. The authors describe the clinical characteristics of drusenoid retinal pigment epithelium detachments (DPEDs and make a review of the DPEDs related in the international literature. We related in this revision paper the multimodal advanced image exams in two cases of dusenoid retinal pigment epithelium detachments (DPEDs and the general characteristics of thisfinding associated with Dry Macular degeneration.Upon examination of the ocular fundusDPEDs emerge as well-circumscribed yellow or yellow–white elevations of the RPE that are usually found within the macula.They may show scalloped borders and a slightly irregular surface. When visualized using fluorescein angiography (FA,DPEDs are typically described as faint hyper-fluorescent in the early phase followed by a slow increase in fluorescence throughout the transit stage of the study without late leakage. With optical coherence tomography (OCT, drusenoid PEDs usually show a smooth contour of the detached hyperreflective RPE band that may have an undulating appearance.Drusenoid PEDs encompass far above the ground possibility type of "dry" AMD that develops in relationship with large confluent soft drusen.At this point no treatment is utilized in drusenoid retinal pigment epithelium detachment(DPEDs.

  7. Characterization of pre-hispanic pigments by modern analytical techniques

    International Nuclear Information System (INIS)

    Ortega A, M.

    2003-01-01

    In this work, the study of mural painting pigments from two archaeological sites (The Great Temple in Mexico city and Cacaxtla) was performed to know their materials composition, identify their structural characteristics and properties by using modern analytical techniques. Blue, ochre, red and black pigments of Mexica culture (1325-1521 a.C. / late Post Classic period); blue, ochre, red, brown, pink, green and white of Olmeca- Xicalanca culture (700-900 a.C. / Epiclassic period) were studied. Data about materials used, technological evolution, mineralogical background, cultural interchange and origin was obtained. Environmental exposition of these paintings since their discovering has produced changes and damage on their materials. Therefore, stability of some pigments has been notorious, ''Maya Blue'' specially presents extraordinary resistance to diluted and concentrated acids and alkalis including boiling condition, acqua regia, solvents, oxidant and reducing agents, moderate heat and biocorrosi6n; for that reason its study was emphasized. ''Maya Blue'' pigment was synthesized in laboratory using the processes described by historic sources (with indigophera suffruticosa leaves and synthetic indigo) up to obtain a stable pigment including acqua regia action. Clay matrix sorbs nearly 0.4 weight percent of organic dye, which cover 79% of palygorskita surface area. (Author)

  8. Related allopolyploids display distinct floral pigment profiles and transgressive pigments.

    Science.gov (United States)

    McCarthy, Elizabeth W; Berardi, Andrea E; Smith, Stacey D; Litt, Amy

    2017-01-01

    Both polyploidy and shifts in floral color have marked angiosperm evolution. Here, we investigate the biochemical basis of the novel and diverse floral phenotypes seen in allopolyploids in Nicotiana (Solanaceae) and examine the extent to which the merging of distinct genomes alters flavonoid pigment production. We analyzed flavonol and anthocyanin pigments from Nicotiana allopolyploids of different ages (N. tabacum, 0.2 million years old; several species from Nicotiana section Repandae, 4.5 million years old; and five lines of first-generation synthetic N. tabacum) as well as their diploid progenitors. Allopolyploid floral pigment profiles tend not to overlap with their progenitors or related allopolyploids, and allopolyploids produce transgressive pigments that are not present in either progenitor. Differences in floral color among N. tabacum accessions seems mainly to be due to variation in cyanidin concentration, but changes in flavonol concentrations among accessions are also present. Competition for substrates within the flavonoid biosynthetic pathway to make either flavonols or anthocyanins may drive the differences seen among related allopolyploids. Some of the pigment differences observed in allopolyploids may be associated with making flowers more visible to nocturnal pollinators. © 2017 Botanical Society of America.

  9. Metal concentration at surface water using multivariate analysis and ...

    African Journals Online (AJOL)

    This study defined the concentration of metals in Kerteh and Paka River water and their potential health risk towards human. 54 water samples were collected and analyzed using ICP-OES. Results revealed that most of the stations in Kerteh River gave the higher concentration of Cd, Cu, Zn, Co, Ni, As, Cr and Pb compared ...

  10. Pigmented poroid neoplasm mimicking nodular melanoma.

    Science.gov (United States)

    Mitsuishi, Tsuyoshi; Ansai, Shin-ichi; Ueno, Takashi; Kawana, Seiji

    2010-06-01

    We reported the case of a 92-year-old woman with a pigmented and non-pigmented surface of the pedunculated nodule on her lower leg. Microscopic examination revealed that this nodule consisted of a component of small, dark, homogenous, poroid cells and cuticular cells in the dermis. The histopathological features of the lesion were consistent with poroid neoplasm. Immunohistochemistry showed that HMB-45 and Melan-A were positive in malanocytes and melanophages of the pigmented areas. Unlike most poroid neoplasms, this case showed pigmented lesion mimicked nodular melanoma.

  11. The visual pigment cyanide effect.

    Science.gov (United States)

    Crescitelli, F; Karvaly, B

    1989-12-01

    The visual pigment of the Tokay gecko (Gekko gekko) with its in situ absorption maximum at 521 nm has its spectral position at 500 to 505 nm when chloride-deficient digitonin is used for the extraction. In this case the addition of chloride or bromide to the extract restores the maximum to 521 nm. This property, characteristic of gecko pigments in general, does not occur with any of the rhodopsins that have been tested. Simple salts of cyanide, a pseudohalogenoid with an ionic radius close to those of chloride and bromide and/or its hydrolysis product attacks both this gecko pigment and rhodopsins in the dark. This is seen as a slow thermal loss of photopigment if (sodium) cyanide is present at concentrations above 40 mM for the gecko pigment and 150 mM for the rhodopsins of the midshipman (Porichthys notatus) and of the frog (Rana pipiens). In all cases the loss of the photopigment is accompanied by the appearance of a spectral product with maximum absorption at about 340 nm. Cyanide addition has no effect on the photosensitivity of the native pigments and neither does it alter, as do chloride, bromide and other anions, the spectral absorbance curve. The spectral product at 340 nm also appears when the visual pigments are photolyzed in the presence of cyanide salts below the threshold concentrations given above. Incubation of digitonin-solubilized all-trans-retinal with (sodium) cyanide leads to a reaction product with absorption spectrum similar to that obtained with visual pigments under comparable conditions.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. DFT study of anthocyanidin and anthocyanin pigments for Dye-Sensitized Solar Cells: Electron injecting from the excited states and adsorption onto TiO2 (anatase) surface

    Science.gov (United States)

    Marcano, Emildo

    2017-06-01

    We explored, the absorption spectra, excited states and electronic injection parameters of anthocyanidin and anthocyanin pigments using the level of theory (TD)CAM-B3LYP/6-31+G(d,p). For the most isolated dyes, the distribution pattern of HOMO and LUMO spreads over the whole molecules, which lead an efficient electronic delocalization. The calculated light harvesting efficiencies (LHEs) are all near unity. Methoxy group in peonidin molecule lead the largest oscillator strength and LHE. The presence of water lead a higher spontaneous electronic inject process, with ΔGinject average of -1.14 eV. The ΔGinject order is peonidin anthocyanin-(TiO2)30 complex was calculated to be from 17 to 24 eV, indicating both, the strong interactions between the dyes and the anatase (TiO2) surface and stronger electronic coupling strengths of the anthocyanin-(TiO2)30 complex, which corresponded to higher observed η. The HOMO and LUMO shape showed the electrons delocalized predominantly on the anthocyanin structure while the LUMO + 1 shape is localized into the (TiO2)30 surface. Therefore, we expected a electronic injection from HOMO to LUMO + 1 in the anthocyanin-(TiO2)30 adsorption complex, after the light absorption.

  13. Complex Surface Concentration Gradients by Stenciled "Electro Click Chemistry"

    DEFF Research Database (Denmark)

    Hansen, Thomas Steen; Lind, Johan Ulrik; Daugaard, Anders Egede

    2010-01-01

    Complex one- or two-dimensional concentration gradients of alkynated molecules are produced on azidized conducting polymer substrates by stenciled "electro click chemistry". The latter describes the local electrochemical generation of catalytically active Cu(I) required to complete a "click...... reaction" between alkynes and azides at room temperature. A stencil on the counter electrode defines the shape and multiplicity of the gradient(s) on the conducting polymer substrate, while the specific reaction conditions control gradient steepness and the maximum concentration deposited. Biologically...

  14. Assessment of Heavy Metals Concentrations in the Surface Water of ...

    African Journals Online (AJOL)

    The digested samples were analyzed for Fe, Cr, Cu, Zn and Pb using Atomic Absorption Spectrophotometer (Model IL250). The seasonal sequence of heavy metals concentrations showed Zn>Fe>Cr>Cu>Pb and Fe>Zn>Cr>Cu>Pb in dry and wet seasons respectively, while that of annual was Cr>Fe>Zn>Cu>Pb. The results ...

  15. Trapped surfaces due to concentration of gravitational radiation

    International Nuclear Information System (INIS)

    Beig, R.; O Murchadha, N.

    1991-01-01

    Sequences of global, asympotically flat solutions to the time-symmetric initial value constraints of general relativity in vacuo are constructed which develop outer trapped surfaces for large values of the argument. Thus all such configurations must gravitationally collapse. A new proof of the positivity of mass in the strong-field regime is also found. (Authors) 22 refs

  16. Lead Concentrations and Risk Exposure Assessment in Surface ...

    African Journals Online (AJOL)

    ADOWIE PERE

    µm, < 250 µm, and < 75 µm of surface soils at undeveloped residential lands leased to auto-mechanic artisans for a minimum of ten years and estimated exposure risk for children that will reside on the polluted lands after the lease periods. Soil-Pb levels ranges obtained were ... Other factors considered were closeness to.

  17. Concentration distributions of thoron and radon near the ground surface

    Energy Technology Data Exchange (ETDEWEB)

    Katase, Akira [Tohwa Univ., Fukuoka (Japan). Faculty of Engineering

    1996-12-01

    One dimensional diffusion model with a constant diffusion coefficient is applied to the thoron concentration distributions in air above the ground. The experimental distributions are well described by the exponential function obtained from the model. Diffusion coefficients and thoron exhalation rates are estimated from the measured distributions, which are the average values for three months. The present values of thoron exhalation are however several times as small as those measured by other researchers. (author)

  18. The relationship between the violet pigment PP-V production and intracellular ammonium level in Penicillium purpurogenum

    OpenAIRE

    Kojima, Ryo; Arai, Teppei; Matsufuji, Hiroshi; Kasumi, Takafumi; Watanabe, Taisuke; Ogihara, Jun

    2016-01-01

    Penicillium purpurogenum is the fungus that produces an azaphilone pigment. However, details about the pigment biosynthesis pathway are unknown. The violet pigment PP-V is the one of the main pigments biosynthesized by this fungus. This pigment contains an amino group in a pyran ring as its core structure. We focused on this pigment and examined the relationship between intracellular ammonium concentration and pigment production using glutamine as a nitrogen source. The intracellular ammonium...

  19. Modeling of surface dust concentrations using neural networks and kriging

    Science.gov (United States)

    Buevich, Alexander G.; Medvedev, Alexander N.; Sergeev, Alexander P.; Tarasov, Dmitry A.; Shichkin, Andrey V.; Sergeeva, Marina V.; Atanasova, T. B.

    2016-12-01

    Creating models which are able to accurately predict the distribution of pollutants based on a limited set of input data is an important task in environmental studies. In the paper two neural approaches: (multilayer perceptron (MLP)) and generalized regression neural network (GRNN)), and two geostatistical approaches: (kriging and cokriging), are using for modeling and forecasting of dust concentrations in snow cover. The area of study is under the influence of dust emissions from a copper quarry and a several industrial companies. The comparison of two mentioned approaches is conducted. Three indices are used as the indicators of the models accuracy: the mean absolute error (MAE), root mean square error (RMSE) and relative root mean square error (RRMSE). Models based on artificial neural networks (ANN) have shown better accuracy. When considering all indices, the most precision model was the GRNN, which uses as input parameters for modeling the coordinates of sampling points and the distance to the probable emissions source. The results of work confirm that trained ANN may be more suitable tool for modeling of dust concentrations in snow cover.

  20. Isopleths of surface air concentration and surface air kerma rate due to a radioactive cloud released from a stack (3)

    International Nuclear Information System (INIS)

    Tachibana, Haruo; Kikuchi, Masamitsu; Sekita, Tsutomu; Yamaguchi, Takenori

    2004-06-01

    This report is a revised edition of 'Isopleths of Surface Air Concentration and Surface Air Absorbed Dose Rate due to a Radioactive Cloud Released from a Stack(II) '(JAERI-M 90-206) and based on the revised Nuclear Safety Guidelines reflected the ICRP1990 Recommendation. Characteristics of this report are the use of Air Karma Rate (Gy/h) instead of Air Absorbed Dose Rate (Gy/h), and the record of isopleths of surface air concentration and surface air karma rate on CD-ROM. These recorded data on CD-ROM can be printed out on paper and/or pasted on digital map by personal computer. (author)

  1. Overview of plant pigments

    Science.gov (United States)

    Chlorophylls, carotenoids, flavonoids and betalains are four major classes of biological pigments produced in plants. Chlorophylls are the primary pigments responsible for plant green and photosynthesis. The other three are accessary pigments and secondary metabolites that yield non-green colors and...

  2. Program for estimating surface air concentrations of NPP discharge radionuclides

    International Nuclear Information System (INIS)

    Ivanov, E.A.; Ramzina, T.V.; Sokolova, E.Yu.

    1986-01-01

    Methods for calculating short-term values of ground-level specific activity in the NPP region and the values averaged for an extended period are described. These methods are realized in the LAURA program on the FORTRAN 4 language for the ES-1033 computer with the OS ES translator and the EMQ-666 computer. As a result of program execution, the user receives the following information: 1) the table for radionuclide surface specific activity values depending on the direction and distance from the source; the wind rose matrix and conditional probabilities of the atmosphere stability category; 2) the map of isolines of radionuclide specific activity in a grid given in polar coordinates with marks of level lines according to their values

  3. Seasonal variability of sea surface chlorophyll-a of waters around ...

    Indian Academy of Sciences (India)

    Lanka. Here, the variability of surface phytoplankton pigments in Indian Ocean waters around Sri Lanka has been studied using CZCS raw data. The knowledge of surface pigment concentrations can be used in the location upwelling areas off the coast. When upwelling brings nutrients to sunlit waters primary production.

  4. Irradiation induced surface segregation in concentrated alloys: a contribution

    International Nuclear Information System (INIS)

    Grandjean, Y.

    1996-01-01

    A new computer modelization of irradiation induced surface segregation is presented together with some experimental determinations in binary and ternary alloys. The model we propose handles the alloy thermodynamics and kinetics at the same level of sophistication. Diffusion is described at the atomistic level and proceeds vis the jumps of point defects (vacancies, dumb-bell interstitials): the various jump frequencies depend on the local composition in a manner consistent with the thermodynamics of the alloy. For application to specific alloys, we have chosen the simplest statistical approximation: pair interactions in the Bragg Williams approximation. For a system which exhibits the thermodynamics and kinetics features of Ni-Cu alloys, the model generates the behaviour parameters (flux and temperature) and of alloy composition. Quantitative agreement with the published experimental results (two compositions, three temperatures) is obtained with a single set of parameters. Modelling austenitic steels used in nuclear industry requires taking into account the contribution of dumbbells to mass transport. The effects of this latter contribution are studied on a model of Ni-Fe. Interstitial trapping on dilute impurities is shown to delay or even suppress the irradiation induced segregation. Such an effect is indeed observed in the experiments we report on Fe 50 Ni 50 and Fe 49 Ni 50 Hf 1 alloys. (author)

  5. Production of Monascus-like pigments

    DEFF Research Database (Denmark)

    2012-01-01

    The present invention relates to a method for producing one or more Monascus-like pigment composition from Penicillium species comprising: a) providing a cultivation medium comprising a high concentration of C-and N-sources and a high C/N molar ratio, b) adjusting pH to about 5 to 8, c) inoculating...... the cultivation medium with an inoculum of Penicillium to form a cultivation composition; d) cultivating the inoculated cultivation composition of (c); e) separating the one or more produced pigment compositions. The method of the invention may be used for producing Monascus-like pigment compositions for use...... as colouring agents in food items or non food items. The inventions further relates to Monascus-like pigment composition obtainable by a method of the inventions as well as use of the pigments....

  6. [Near surface CO2 concentration and its quantitative relationship with character of underlying surface in Shanghai City, China].

    Science.gov (United States)

    Pan, Chen; Zhu, Xi-yang; Jia, Wen-xiao; Yang, Fang; Liu, Ming; Xiang, Wei-ning

    2015-07-01

    Land use change and fossil fuel combustion due to urbanization have a significant effect on global carbon cycle and climate change. It's important to have an explicit understanding of the spatial distribution of CO2 to recognize and control GHG emission, which is helpful to reduce human-induced contribution to global climate change. The study area of this project was set in the city of Shanghai with intensive human activity and rapid urbanization. The monitoring of near surface CO2 concentration along 3 transects was conducted across an urban-rural gradient by means of near infrared gas analyzer Li-840A in spring, 2014. Remote sensing data were also used to derive underlying surface information. Further quantitative analysis of the mechanism of CO2 concentration's response to the characteristics of underlying surface was presented in this paper. The results showed that the average near surface CO2 concentration was (443.4±22.0) µmol . mol-1. CO2 concentration in city center was in average 12.5% (52.5 µLmol . mol-1) higher than that in the suburban area. Also, CO2 concentration showed a significant spatial differentiation, with the highest CO2 concentration in the northwest, the second highest in the southwest, and the lowest in the southeast, which was in accordance with the urbanization level of the underlying surface. The results revealed that the vegetation coverage rate (CVeg) was an important indicator to describe near surface CO2 concentration with a negative correlation, and the impervious surface area coverage rate (CISA) had lower explanatory power with a positive correlation. The study also found that the determination coefficient (R2) between CO2 concentration (CCO2) and CISA or CVeg achieved its highest value when the buffer distance was 5 km, and their quantitative relationships be described by a stepwise regression equation: CCO2=0.32CISA-0.89CVeg+445.13 (R2 =0.66, P<0.01).

  7. The deconvolution of sputter-etching surface concentration measurements to determine impurity depth profiles

    International Nuclear Information System (INIS)

    Carter, G.; Katardjiev, I.V.; Nobes, M.J.

    1989-01-01

    The quasi-linear partial differential continuity equations that describe the evolution of the depth profiles and surface concentrations of marker atoms in kinematically equivalent systems undergoing sputtering, ion collection and atomic mixing are solved using the method of characteristics. It is shown how atomic mixing probabilities can be deduced from measurements of ion collection depth profiles with increasing ion fluence, and how this information can be used to predict surface concentration evolution. Even with this information, however, it is shown that it is not possible to deconvolute directly the surface concentration measurements to provide initial depth profiles, except when only ion collection and sputtering from the surface layer alone occur. It is demonstrated further that optimal recovery of initial concentration depth profiles could be ensured if the concentration-measuring analytical probe preferentially sampled depths near and at the maximum depth of bombardment-induced perturbations. (author)

  8. Influence of inundation of ground surface on 222Rn concentrations in shallow groundwater

    International Nuclear Information System (INIS)

    Hamada, Hiromasa; Abenney-Mickson, Stephen; Komae, Takami

    2004-01-01

    Radon-222 ( 222 Rn) is a good indicator for analyzing the speed at which surface water infiltrates the ground and reaches groundwater. Preferential flow, which is very fast, is expected to occur when the ground surface is inundated. Piston flow, which is very slow, is expected to occur when the ground surface is not inundated but is only sprinkled with water such as during a light rainfall. We hypothesized that preferential flow would reduce the 222 Rn concentration in groundwater but that piston flow would not; our study verified this hypothesis experimentally. We then measured 222 Rn concentration in groundwater for one year in low-land and upland locations. 222 Rn concentrations in groundwater decreased at the lowland site, where the ground surface was inundated by irrigation and heavy rainfall, while 222 Rn concentrations in groundwater did not decrease at the upland site, where the ground surface was not inundated. (author)

  9. Natural Pigment Production by Monascus purpureus: Improving the yield in a bioreactor based on statistical analysis

    Directory of Open Access Journals (Sweden)

    Atieh Seyedin

    2015-03-01

    Full Text Available AbstractDue to the especial properties such as high growth rates, easy extraction as well as high yields, using microorganisms in comparison to other sources is more chosen for pigment production. Pigments are used in food industries as natural colorants and preservatives, they also have pharmaceutical applications. In this study, fungus Monascus purpureus PTCC 5303 have been used to produce red, orange and yellow pigments. At first significant variables were screened based on plackett-Burman design and then the optimized value of two effectivefactors such as yeast extract and K2HPO4 concentrations wasoptimized byresponse surface method. Optimal levels of factors were found to be 2/75 g/L yeast extract and1/5 g/LK2HPO4 respectively. Antimicrobial activity of pigments was evaluated on Gram-positive foodborne bacteria under optimal conditionswhich resultsshowed inhibitory effects. Moreover Pigments production at optimal conditions in a bioreactor was evaluatedand the rate of production of red, orange and yellow pigments, 2.05, 1.55 and 0.78 (ODU/ml were observed respectively.  

  10. Model of the in vivo spectral absorption of algal pigments. Part 1. Mathematical apparatus

    Directory of Open Access Journals (Sweden)

    Bogdan Wo¼niak

    2000-06-01

    Full Text Available Existing statistical models of in vivo light absorption by phytoplankton (Wozniak & Ostrowska 1990, Bricaud et al. 1995, 1998 describe the dependence of the phytoplankton specific spectral absorption coefficient a*pl(λ on the chlorophyll a concentration Ca in seawater. However, the models do not take into account the variability in this relationship due to phytoplankton acclimation. The observed variability in the light absorption coefficient and its components due to various pigments with depth and geographical position at sea, requires further accurate modelling in order to improve satellite remote sensing algorithms and interpretation of ocean colour maps.      The aim of this paper is to formulate an improved model of the phytoplankton spectral absorption capacity which takes account of the pigment composition and absorption changes resulting from photo- and chromatic acclimation processes, and the pigment package effect. It is a synthesis of earlier models and the following statistical generalisations: (1 statistical relationships between various pigment group concentrations and light field properties in the sea (described by Majchrowski & Ostrowska 2000, this volume; (2 a model of light absorption by phytoplankton capable of determining the mathematical relationships between the spectral absorption coefficients of the various photosynthetic and photoprotecting pigment groups, and their concentrations in seawater (Wozniak et al. 1999; (3 bio-optical models of light propagation in oceanic Case 1 Waters and Baltic Case 2 Waters (Wozniak et al. 1992a,b, 1995a,b. The generalised model described in this paper permits the total phytoplankton light absorption coefficient in vivo as well as its components related to the various photosynthetic and photoprotecting pigments to be determined using only the surface irradiance PAR(0+ surface chlorophyll concentration Ca(0 and depth z in the sea as input data.

  11. Quantifying the impact of climate change on enteric waterborne pathogen concentrations in surface water

    NARCIS (Netherlands)

    Hofstra, N.

    2011-01-01

    Climate change, among other factors, will impact waterborne pathogen concentrations in surface water worldwide, possibly increasing the risk of diseases caused by these pathogens. So far, the impacts are only determined qualitatively and thorough quantitative estimates of future pathogen

  12. Laser surface processing with controlled nitrogen-argon concentration levels for regulated surface life time

    Science.gov (United States)

    Obeidi, M. Ahmed; McCarthy, E.; Brabazon, D.

    2018-03-01

    Laser surface modification can be used to enhance the mechanical properties of a material, such as hardness, toughness, fatigue strength, and corrosion resistance. Surface nitriding is a widely used thermochemical method of surface modification, in which nitrogen is introduced into a metal or other material at an elevated temperature within a furnace. It is used on parts where there is a need for increased wear resistance, corrosion resistance, fatigue life, and hardness. Laser nitriding is a novel method of nitriding where the surface is heated locally by a laser, either in an atmosphere of nitrogen or with a jet of nitrogen delivered to the laser heated site. It combines the benefits of laser modification with those of nitriding. Recent work on high toughness tool steel samples has shown promising results due to the increased nitrogen gas impingement onto the laser heated region. Increased surface activity and nitrogen adsorption was achieved which resulted in a deeper and harder surface compared to conventional hardening methods. In this work, the effects of the laser power, pulse repetition frequency, and overlap percentage on laser surface treatment of 316 L SST steel samples with an argon-nitrogen jet will be presented. Resulting microstructure, phase type, microhardness, and wear resistance are presented.

  13. Effect of soil surface management on radiocesium concentrations in apple orchard and fruit

    International Nuclear Information System (INIS)

    Kusaba, Shinnosuke; Matsuoka, Kaori; Abe, Kazuhiro

    2016-01-01

    We investigated the effect of soil surface management on radiocesium accumulation in an apple orchard in Fukushima Prefecture over 4 years after Tokyo Electric Power Company’s Fukushima Daiichi nuclear power plant accident in mid-March 2011. Different types of soil surface management such as clean cultivation, intertillage management, intertillage with bark compost application, sod culture, and zeolite application were employed. The radiocesium concentrations in soil were higher in the surface layer (0–5 cm) than in the other layers. The radiocesium concentration in the surface layer soil with sod culture in 2014 increased non-significantly compared with that observed in 2011. The radiocesium concentration in the mid-layer soil (5–15 cm) managed with intertillage was higher than that in soil managed using other types of management. The radiocesium amount in the organic matter on the soil surface was the highest in sod culture, and was significantly lower in the management with intertillage. The radiocesium concentration in fruit decreased exponentially during the 4 years in each types of soil surface management. The decrease in radiocesium concentration showed similar trends with each type of soil surface management, even if the concentration in each soil layer varied according to the management applied. Furthermore, intertillage with bark compost application did not affect the radiocesium concentration in fruit. These results suggest that the soil surface management type that affected the radiocesium distribution in the soil or the compost application with conventional practice did not affect its concentration in fruit of apple trees for at least 4 years since the nuclear power plant accident, at a radiocesium deposition level similar to that recorded in Fukushima City. (author)

  14. The Relationship between Gastric Juice Nitrate/Nitrite Concentrations and Gastric Mucosal Surface pH

    OpenAIRE

    Lee, Hae Kyung; Kim, Hyunjung; Kim, Hyung-Keun; Cho, Young-Seok; Kim, Byung-Wook; Han, Sok-Won; Maeng, Lee So; Chae, Hiun-Suk; Kim, Hee Na

    2012-01-01

    Purpose To investigate gastric juice nitrate/nitrite concentration according to mucosal surface pH extent (area) of gastric corpus intimately contacting the gastric juice. Materials and Methods We included ninety-nine patients with dyspepsia. To evaluate gastric mucosal surface pH and its extent, gastric chromosocpy was performed by spraying phenol red dye on the corpus mucosa and estimating the extent of area with color changed. Nitrate/nitrite concentrations and pH of gastric juice were mea...

  15. Genetic disorders of pigmentation.

    Science.gov (United States)

    Passeron, Thierry; Mantoux, Frédéric; Ortonne, Jean-Paul

    2005-01-01

    More than 127 loci are actually known to affect pigmentation in mouse when they are mutated. From embryogenesis to transfer of melanin to the keratinocytes or melanocytes survival, any defect is able to alter the pigmentation process. Many gene mutations are now described, but the function of their product protein and their implication in melanogenesis are only partially understood. Each genetic pigmentation disorder brings new clues in the understanding of the pigmentation process. According to the main genodermatoses known to induce hypo- or hyperpigmentation, we emphasize in this review the last advances in the understanding of the physiopathology of these diseases and try to connect, when possible, the mutation to the clinical phenotype.

  16. Solitary black pigment stones

    International Nuclear Information System (INIS)

    Wolpers, C.; Wosiewitz, U.

    1986-01-01

    Solitary pigment stones of the gall-bladder are rare (1.7%). 82,5% are radiopaque, 17.5% radiolucent. 64,8% of radiopaque solitary pigment stones have the structure of a cockade. Such cockades take years to develop. Solitary cholesterol stones with a nucleus of a radiopaque pigment stone should not be treated for litholysis. 8% of solitary cholesterol stones with a cross diameter below 15 mm. possess a radiolucent pigment stone nucleus. X-ray diagnosis for selecting litholytic treatment remains the safest method, especially if the radiologist compares his films regularly with the specimens after surgery. (orig.) [de

  17. Effect of intravitreal ranibizumab injections on aqueous humour concentrations of vascular endothelial growth factor and pigment epithelium-derived factor in patients with myopic choroidal neovascularisation.

    Science.gov (United States)

    Costagliola, Ciro; Semeraro, Francesco; dell'Omo, Roberto; Romano, Mario R; Russo, Andrea; Aceto, Fabiana; Mastropasqua, Rodolfo; Porcellini, Antonio

    2015-07-01

    To investigate aqueous humour changes in vascular endothelial growth factor (VEGF) and pigment epithelium-derived factor (PEDF) levels in patients with choroidal neovascularisation (CNV) secondary to pathological myopia (mCNV) before and after intravitreal ranibizumab injection (IVR). This was a prospective, case-control study investigating aqueous levels of VEGF and PEDF in eyes with mCNV treated with IVR. Mean VEGF and PEDF levels in the aqueous humour of control patients were 25.7±4.9 pg/mL and 12.6±3.5 ng/mL, respectively. Lower levels of both VEGF (19.5±5.4 pg/mL) and PEDF (4.7±2.2 ng/mL) were found in patients with mCNV before IVR. After IVR, aqueous VEGF levels significantly reduced to 6.5±2.7 pg/mL, while PEDF levels significantly increased to 35.8±11.4 ng/mL. VEGF and PEDF levels significantly correlated with each other, and with best-corrected visual acuity and central retinal thickness. The VEGF and PEDF levels in aqueous humour were significantly lower in the myopic group than in controls. Moreover, IVR resulted in reduced VEGF and increased PEDF levels in patients with mCNV. In mCNV, neovascularisation is associated with inappropriate VEGF and PEDF expression. A balance between VEGF and PEDF is crucial to prevent CNV development. NCT02175940. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  18. Numerical simulation of the double pits stress concentration in a curved casing inner surface

    Directory of Open Access Journals (Sweden)

    Wei Yan

    2016-12-01

    Full Text Available Sour or sweet oil fields development is common in recent years. Casing and tubing are usually subjected to pitting corrosion because of exposure to the strong corrosion species, such as CO2, H2S, and saline water. When the corrosion pits formed in the casing inner surface, localized stress concentration will occur and the casing strength will be degraded. Thus, it is essential to evaluate the degree of stress concentration factor accurately. This article performed a numerical simulation on double pits stress concentration factor in a curved inner surface using the finite element software ABAQUS. The results show that the stress concentration factor of double pits mainly depends on the ratio of two pits distance to the pit radius (L/R. It should not be only assessed by the absolute distance between the two pits. When the two pits are close and tangent, the maximum stress concentration factor will appear on the inner tangential edges. Stress concentration increased by double pits in a curved casing inner surface is more serious than that in a flat surface. A correction factor of 1.9 was recommended in the curved inner surface double pits stress concentration factor predict model.

  19. Inhibitory effect of 5-iodotubercidin on pigmentation.

    Science.gov (United States)

    Kim, Kyung-Il; Jeong, Hae Bong; Ro, Hyunju; Lee, Jeung-Hoon; Kim, Chang Deok; Yoon, Tae-Jin

    2017-09-02

    Melanin pigments are the primary contributors for the skin color. They are produced in melanocytes and then transferred to keratinocytes, eventually giving various colors on skin surface. Although many depigmenting and/or skin-lightening agents have been developed, there is still a growing demand on materials for reducing pigmentation. We attempted to find materials for depigmentation and/or skin-lightening using the small molecule compounds commercially available, and found that 5-iodotubercidin had inhibitory potential on pigmentation. When HM3KO melanoma cells were treated with 5-iodotubercidin, pigmentation was dramatically reduced. The 5-iodotubercidin decreased the protein level for pigmentation-related molecules such as MITF, tyrosinase, and TRP1. In addition, 5-iodotubercidin decreased the phosphorylation of CREB, while increased the phosphorylation of AKT and ERK. These data suggest that 5-iodotubercidin inhibits melanogenesis via the regulation of intracellular signaling related with pigmentation. Finally, 5-iodotubercidin markedly inhibited the melanogenesis of zebrafish embryos, an in vivo evaluation model for pigmentation. Together, these data suggest that 5-iodotubercidin can be developed as a depigmenting and/or skin-lightening agent. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Surface modification of platelet concentrate bags to reduce biofilm formation and transfusion sepsis.

    Science.gov (United States)

    Wilson-Nieuwenhuis, Joels S T; Dempsey-Hibbert, Nina; Liauw, Christopher M; Whitehead, Kathryn A

    2017-12-01

    Bacterial contamination of blood products poses a major risk in transfusion medicine, including transfusions involving platelet products. Although testing systems are in place for routine screening of platelet units, the formation of bacterial biofilms in such units may decrease the likelihood that bacteria will be detected. This work determined the surface properties of p-PVC platelet concentrate bags and investigated how these characteristics influenced biofilm formation. Serratia marcescens and Staphylococcus epidermidis, two species commonly implicated in platelet contamination, were used to study biofilm growth. The platelet concentrate bags were physically flattened to determine if reducing the surface roughness altered biofilm formation. The results demonstrated that the flattening process of the platelet bags affected the chemistry of the surface and reduced the surface hydrophobicity. Flattening of the surfaces resulted in a reduction in biofilm formation for both species after 5 days, with S. marcescens demonstrating a greater reduction. However, there was no significant difference between the smooth and flat surfaces following 7 days' incubation for S. marcescens and no significant differences between any of the surfaces following 7 days' incubation for S. epidermidis. The results suggest that flattening the p-PVC surfaces may limit potential biofilm formation for the current duration of platelet storage time of 5 days. It is hoped that this work will enhance the understanding of how surface properties influence the development of microbial biofilms in platelet concentrate bags in order to devise a solution to discourage biofilm formation. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Anthropogenic Pollution in Izmit Bay: Heavy Metal Concentrations in Surface Sediments

    OpenAIRE

    YAŞAR, D.

    2014-01-01

    The extent of marine pollution in İzmit Bay is studied using geochemical data in surface sediments. The concentrations of 41 elements in 24 samples establish that surface sediments in inner and central İzmit Bay display significant enrichments in Ag, As, Cd, Cr, Co, Cu, Hg, Mo, P, Pb, Sb, Ti, V, and Zn associated with high concentrations of total organic carbon and sulphur. Geo-accumulation indices indicate that the inner and central İzmit Bay surface sediments are moderately to very...

  2. Effect of concentration and temperature on surface tension of sodium hyaluronate saline solutions.

    Science.gov (United States)

    Ribeiro, Walkiria; Mata, José Luis; Saramago, Benilde

    2007-06-19

    The effect of concentration and temperature on the surface tension of sodium hyaluronate (NaHA) saline solutions was investigated using the technique of the shape of pendant drops. The decay rate of the surface tension with the increase of NaHA concentration was well-described by the empirical Hua-Rosen equation. Adsorption at the air-liquid interface was estimated using the Gibbs equation. The temperature dependence of a dilute solution and a semidilute entangled solution was numerically fitted with a second-order polynomial equation. The surface behavior of the NaHA saline solutions was interpreted in terms of their known viscoelastic properties.

  3. Dependence of Ideality Factor in Lateral PNP Transistors on Surface Carrier Concentration

    Science.gov (United States)

    Li, Xingji; Yang, Jianqun; Barnaby, Hugh J.; Galloway, Kenneth F.; Schrimpf, Ronald D.; Fleetwood, Daniel M.; Liu, Chaoming

    2017-06-01

    The influence of surface carrier concentration on the ideality factor of excess base current (ΔIB) in gated lateral PNP (GLPNP) bipolar junction transistors (BJTs) induced by 1-MeV electrons is investigated. ΔIB in LPNP BJTs is impacted by the surface carrier density and radiation-induced interface traps. In GLPNP BJTs, the surface carrier concentration can be controlled by the voltage applied to a gate over the base region. The ideality factor changes after irradiation, and its dependence on emitter-base voltage (VEB) is a function of gate voltage. For the irradiated devices, as the gate voltage decreases from +20 to -5 V, the ideality factor for excess base current changes from a single slope to two-slope behavior. The majority carrier concentration at the surface of the base, controlled by the gate voltage, impacts the excess base current and its ideality factor.

  4. The effects of large-scale atmospheric flows on berylium-7 activity concentration in surface air.

    Science.gov (United States)

    Arkian, Foroozan; Meshkatee, Amir-Hussain; Bidokhti, Ali Akbar

    2010-09-01

    Understanding the exchange mechanism between stratosphere and troposphere is one of the most important concerns of meteorologists and climatologists for decades. Different methods are being adopted to study those mechanisms. One of those methods is the study upon the tropospheric concentration of conserve or passive entities with stratospheric origin. One of those passive entities is (7)Be that is produced upon the incident of cosmic rays on light atmospheric nuclei in the stratosphere. The availability of 5 years observations of (7)Be concentration in surface air in Tehran (35 degrees 41(') N, 51 degrees 18(') E) encouraged us to investigate meteorological condition effect on the surface concentration of (7)Be. Also, the intention was to see if there was any intrusion of stratospheric air into the troposphere at the time of high surface concentration of (7)Be and scavenging mechanism when the concentration was low. During the course of this study, it has been found that (7)Be concentration is high whenever there is a jet stream over Tehran. Since high-level jet streams normally form near tropopause folding, it could be interpreted as a sign of the intrusion of stratospheric air into the troposphere. It was also found that high concentration of (7)Be in the Tehran surface air in summer is associated with an upper ridge on 500 hPa surface located east of the city, and low concentration in winter is associated with an upper trough. The latter normally is seen whenever there is precipitation that suggests wet scavenging could be the reason for that observed low concentration.

  5. Effects of different sulfuric acid etching concentrations on PEEK surface bonding to resin composite.

    Science.gov (United States)

    Chaijareenont, Pisaisit; Prakhamsai, Sasiprapha; Silthampitag, Patcharawan; Takahashi, Hidekazu; Arksornnukit, Mansuang

    2018-01-26

    This study evaluated the effects of surface pretreatment with different concentrations of sulfuric acid etching on surface properties and bonding between Polyetheretherketone (PEEK) and a resin composite. Six groups of surface pretreatment (no pretreatment, etched with 70, 80, 85, 90, and 98% sulfuric acid for 60 s) were treated on PEEK. Surface roughness, scanning electron microscopy (SEM) and atomic force microscopy (AFM) analyses were examined. Shear bond strength (SBS) and cross-sectional observations of the interfaces were performed. One-way ANOVA analysis revealed differences in surface roughness and SBS between groups. The 90 and 98% sulfuric acid etching significantly achieved the highest SBS (psulfuric acid etching were suggested to be the optimal concentration to improve adhesion between PEEK and the resin composite.

  6. Comparison of two estimation methods for surface area concentration using number concentration and mass concentration of combustion-related ultrafine particles

    Science.gov (United States)

    Park, Ji Young; Raynor, Peter C.; Maynard, Andrew D.; Eberly, Lynn E.; Ramachandran, Gurumurthy

    Recent research has suggested that the adverse health effects caused by nanoparticles are associated with their surface area (SA) concentrations. In this study, SA was estimated in two ways using number and mass concentrations and compared with SA (SA meas) measured using a diffusion charger (DC). Aerosol measurements were made twice: once starting in October 2002 and again starting in December 2002 in Mysore, India in residences that used kerosene or liquefied petroleum gas (LPG) for cooking. Mass, number, and SA concentrations and size distributions by number were measured in each residence. The first estimation method (SA PSD) used the size distribution by number to estimate SA. The second method (SA INV) used a simple inversion scheme that incorporated number and mass concentrations while assuming a lognormal size distribution with a known geometrical standard deviation. SA PSD was, on average, 2.4 times greater (range = 1.6-3.4) than SA meas while SA INV was, on average, 6.0 times greater (range = 4.6-7.7) than SA meas. The logarithms of SA PSD and SA INV were found to be statistically significant predictors of the logarithm of SA meas. The study showed that particle number and mass concentration measurements can be used to estimate SA with a correction factor that ranges between 2 and 6.

  7. Reanalysis of and attribution to near-surface ozone concentrations in Sweden during 1990-2013

    Science.gov (United States)

    Andersson, Camilla; Alpfjord, Heléne; Robertson, Lennart; Karlsson, Per Erik; Engardt, Magnuz

    2017-11-01

    We have constructed two data sets of hourly resolution reanalyzed near-surface ozone (O3) concentrations for the period 1990-2013 for Sweden. Long-term simulations from a chemistry-transport model (CTM) covering Europe were combined with hourly ozone concentration observations at Swedish and Norwegian background measurement sites using retrospective variational data analysis. The reanalysis data sets show improved performance over the original CTM when compared to independent observations. In one of the reanalyses, we included all available hourly near-surface O3 observations, whilst in the other we carefully selected time-consistent observations. Based on the second reanalysis we investigated statistical aspects of the distribution of the near-surface O3 concentrations, focusing on the linear trend over the 24-year period. We show that high near-surface O3 concentrations are decreasing and low O3 concentrations are increasing, which is reflected in observed improvement of many health and vegetation indices (apart from those with a low threshold). Using the CTM we also conducted sensitivity simulations to quantify the causes of the observed change, focusing on three factors: change in hemispheric background concentrations, meteorology and anthropogenic emissions. The rising low concentrations of near-surface O3 in Sweden are caused by a combination of all three factors, whilst the decrease in the highest O3 concentrations is caused by European O3 precursor emissions reductions. While studying the impact of anthropogenic emissions changes, we identified systematic differences in the modeled trend compared to observations that must be caused by incorrect trends in the utilized emissions inventory or by too high sensitivity of our model to emissions changes.

  8. AFM Studies of Salt Concentration Effects on the (110) Surface Structure of Tetragonal Lysozyme Crystals

    Science.gov (United States)

    Pusey, Marc Lee; Gorti, Sridhar; Forsythe, Elizabeth; Konnert, John

    2002-01-01

    Previous high resolution AFM studies of the (110) surface of tetragonal chicken egg white lysozyme crystals had shown that only one of two possible molecular surfaces is present, those constituting the completed 43 helices. These suggested that the crystal growth process was by the solution-phase assembly of the growth units, which then attach to the surface. However, the best fit for the imaged surfaces, vs. those predicted based upon the bulk crystallographic coordinates, were obtained when the packing about the 43 helices was "tightened up", while maintaining the underlying crystallographic unit cell spacing. This results in a widening of the gap between adjacent helices, and the top- most layer(s) may no longer be in contact. We postulated that the tightened packing about the helices is a result of the high salt concentrations in the bulk solution, used to crystallize the protein, driving hydrophobic interactions. Once the crystal surface is sufficiently buried by subsequent growth layers the ratio of salt to protein molecules decreases and the helices relax to their bulk crystallographic coordinates. The crystal surface helix structure is thus a reflection of the solution structure, and the tightness of the packing about the 43 helices would be a function of the bulk salt concentration. AFM images of the (110) surface of tetragonal lysozyme crystals grown under low (2%) and high (5%) NaCl concentrations reveal differences in the packing about the 43 helices consistent with the above proposal.

  9. [Microbial sources of pigments].

    Science.gov (United States)

    Cañizares-Villanueva, R O; Ríos-Leal, E; Olvera Ramírez, R; Ponce Noyola, T; Márquez Rocha, F

    1998-01-01

    Pigments from natural sources has been obtained since long time ago, and their interest has increased due to the toxicity problems caused by those of synthetic origin. In this way the pigments from microbial sources are a good alternative. Some of more important natural pigments, are the carotenoids, flavonoids (anthocyanins) and some tetrapirroles (chloropyls, phycobilliproteins). Another group less important are the betalains and quinones. The carotenoids are molecules formed by isoprenoids units and the most important used as colorant are the alpha and beta carotene which are precursors of vitamin A, and some xantophylls as astaxanthin. The pigment more used in the industry is the beta-carotene which is obtained from some microalgae and cyanobacteria. The astaxanthin another important carotenoid is a red pigment of great commercial value, and it is used in the pharmaceutical feed and acuaculture industries. This pigments is mainly obtained from Phaffia rhodozyma and Haematococcus pluvialis and other organisms. The phycobilliproteins obtained from cyanobacteria and some group of algae, have recently been increased on the food industries. In the last years it has been used as fluorescent marker in biochemical assays. Our research group have carried out studies about the factors that improve the production of these pigments obtained from different microbial species as well as the methods for their extraction and application.

  10. Ion transport in pigmentation.

    Science.gov (United States)

    Bellono, Nicholas W; Oancea, Elena V

    2014-12-01

    Skin melanocytes and ocular pigment cells contain specialized organelles called melanosomes, which are responsible for the synthesis of melanin, the major pigment in mammals. Defects in the complex mechanisms involved in melanin synthesis and regulation result in vision and pigmentation deficits, impaired development of the visual system, and increased susceptibility to skin and eye cancers. Ion transport across cellular membranes is critical for many biological processes, including pigmentation, but the molecular mechanisms by which it regulates melanin synthesis, storage, and transfer are not understood. In this review we first discuss ion channels and transporters that function at the plasma membrane of melanocytes; in the second part we consider ion transport across the membrane of intracellular organelles, with emphasis on melanosomes. We discuss recently characterized lysosomal and endosomal ion channels and transporters associated with pigmentation phenotypes. We then review the evidence for melanosomal channels and transporters critical for pigmentation, discussing potential molecular mechanisms mediating their function. The studies investigating ion transport in pigmentation physiology open new avenues for future research and could reveal novel molecular mechanisms underlying melanogenesis.

  11. The Effects of Different Types of Antioxidants (Se, Vitamin E and Carotenoids) in Broiler Diets on the Growth Performance, Skin Pigmentation and Liver and Plasma Antioxidant Concentrations

    OpenAIRE

    F Karadas; S Erdoğan; D Kor; G Oto; M Uluman

    2016-01-01

    Abstract This study investigated the effects of the addition of different antioxidants to broiler diets on their live performance, liver antioxidant composition and concentrations, immune response, and meat and skin color. A total of 945 three-day-old Ross 308 broiler chicks of both genders were randomly allocated to one of nine dietary treatments (n=105), with three replicates 35 chicks per pen, as follows: T1: control (commercially available corn-and soybean-based broiler diet); T2: seleniu...

  12. Long-term variations in the surface air 7Be concentration and climatic changes.

    Science.gov (United States)

    Jiwen, Liu; Starovoitova, Valeriia N; Wells, Douglas P

    2013-02-01

    We have used EML Surface Air Sampling Program (SASP) data to analyze the long-term trend in (7)Be surface concentration and address possible correlation between this long-term trend and climatic changes, namely changes in precipitation patterns and temperature. In this paper we present (7)Be concentration data from 23 sites, spanning over 25 years, all over the world, and extract long-term trend parameter using two independent techniques. The (7)Be concentrations in most stations show a pronounced decreasing trend, potentially corresponding to statistically significant changes in transporting (7)Be from upper atmosphere source to these sites. Weak negative correlation between (7)Be concentration and amount of precipitation was also observed. However, more data from more representative sites around the world are needed the statistical robustness of this trend. Published by Elsevier Ltd.

  13. The osmolyte xylitol reduces the salt concentration of airway surface liquid and may enhance bacterial killing

    Science.gov (United States)

    Zabner, Joseph; Seiler, Michael P.; Launspach, Janice L.; Karp, Philip H.; Kearney, William R.; Look, Dwight C.; Smith, Jeffrey J.; Welsh, Michael J.

    2000-10-01

    The thin layer of airway surface liquid (ASL) contains antimicrobial substances that kill the small numbers of bacteria that are constantly being deposited in the lungs. An increase in ASL salt concentration inhibits the activity of airway antimicrobial factors and may partially explain the pathogenesis of cystic fibrosis (CF). We tested the hypothesis that an osmolyte with a low transepithelial permeability may lower the ASL salt concentration, thereby enhancing innate immunity. We found that the five-carbon sugar xylitol has a low transepithelial permeability, is poorly metabolized by several bacteria, and can lower the ASL salt concentration in both CF and non-CF airway epithelia in vitro. Furthermore, in a double-blind, randomized, crossover study, xylitol sprayed for 4 days into each nostril of normal volunteers significantly decreased the number of nasal coagulase-negative Staphylococcus compared with saline control. Xylitol may be of value in decreasing ASL salt concentration and enhancing the innate antimicrobial defense at the airway surface.

  14. DNA damage in isolated rat hepatocytes exposed to C.I. pigment orange 5 and C.I. pigment yellow 12 by the alkaline comet assay

    DEFF Research Database (Denmark)

    Møller, P; Wallin, Håkan; Grunnet, N

    1998-01-01

    , and C.I. pigment orange 5 is a naphthol-azo pigment. The pigments are virtually insoluble in aqueous solutions, and they have not been tested extensively for toxicological effects. C.I. pigment orange 5 increased the levels of DNA damage at 5 microg/ml (P .../ml (P effect of incubation time (20, 40, and 80 min) of the same concentrations of the pigments was tested. The levels of DNA damage were increased up to 80 min. Both pigments produced DNA damage that was in the same range as the food carcinogen 2-amino-3,8-dimethylimidazo[4,5-f......]quinoxaline. Our data indicate that both C.I. pigment orange 5 and C.I. pigment yellow 12 are genotoxic in hepatocytes with metabolizing capacities. However, further investigation of the metabolism and disposition are required for the evaluation of the safety of these pigments....

  15. Helium concentration in tungsten nano-tendril surface morphology using Elastic Recoil Detection

    International Nuclear Information System (INIS)

    Woller, K.B.; Whyte, D.G.; Wright, G.M.; Doerner, R.P.; De Temmerman, G.

    2013-01-01

    Helium (He) concentrations in tungsten nano-tendrils (W fuzz) have been measured for the first time using Elastic Recoil Detection (ERD). Fuzzy and non-fuzzy W surfaces were analyzed in order to illuminate the role of He in the transition in surface morphologies. Samples grown in the PISCES-A and PILOT-PSI experiments allowed a survey of surface temperature ranging from T s = 470–2595 K and of He fluence on the order of Φ He ∼ 10 24 –10 27 ions/m 2 . He concentrations measured in the bulk of W fuzz layers are roughly uniform with bulk He concentration 1–4 at.% while samples with just He in the near surface peaked at 1–2 at.%. This confirms that the nano-tendrils are filled with high pressure He bubbles since the solubility of He in W is ∼10 −5 at.%. This indicates that the ∼1000 K temperature fuzz-growth threshold is determined by the response of the W, not the near-surface He concentration

  16. Concentration of uranium in the drinking and surface water around the WIPP site

    International Nuclear Information System (INIS)

    Khaing, H.; Lemons, B.G.; Thakur, P.

    2016-01-01

    Activity concentration of uranium isotopes ( 238 U, 234 U and 235 U) were analyzed in drinking and surface water samples collected in the vicinity of the WIPP site using alpha spectroscopy. The purpose of this study was to investigate the changes in uranium concentrations (if any) in the vicinity of the WIPP site and whether the February 14, 2014 radiation release event at the WIPP had any detectable impact on the water bodies around the WIPP. (author)

  17. Co-deposition of Pigment Particles with Nickel through Electrodeposition

    Science.gov (United States)

    Kim, Do Yoon

    This research focuses on the synthesis of a nickel-pigment composite coating in an effort to produce coloured nickel electrodeposits via the codeposition approach. A blue pigment, Copper Phthalocyanine (CuPc) Blue was codeposited to create Ni-CuPc composite coatings. Top surface and cross-sectional Scanning Electron Microscopy (SEM) images confirmed the codeposition of pigment particles within the nickel matrix throughout the entire coating thickness. The top surface of the Ni-CuPc composite coating showed an unexpected metallic copper colour. X-Ray Photoelectron Spectroscopy (XPS) analysis indicates the presence of metallic copper confined to the top surface. It was speculated that this phenomenon is due to the galvanic displacement reaction between copper from the pigment and nickel from the matrix. Upon removing the copper surface layer the colour of the composite remained metallic silver despite the presence of the pigment particles.

  18. Concentration polarization and desalination in nanochannels: Effect of surface charge dynamics

    Science.gov (United States)

    Andersen, Mathias B.; Bruus, Henrik; Mani, Ali; Bazant, Martin Z.

    2011-11-01

    Mani, Zangle, and Santiago (Langmuir, 25, 3898-3916) have shown that at microchannel-nanochannel junctions the coupled effect of concentration polarization and surface conduction can lead to long range propagation of bulk ion-depletion shocks. Essential for this phenomena is the surface charge which for many materials depends on both the concentration and the pH of the local bulk electrolyte. Standard models predict that the surface charge decreases with decreasing concentration leading to the contradictory expectation that there is little or no surface charge in the depleted region and hence no mechanism to sustain long range propagation of desalination shocks. We show that this simple prediction fails to take into account axial transport terms. As such, we couple a surface charge model with the Poisson-Nernst-Planck equations for electric potential and ionic species combined with the Navier-Stokes and continuity equations for fluid velocity. Motivated by experimental work we consider steady-state solutions at the dead end of a nanochannel against a membrane, a scenario where especially space charge and electroosmotic flow are important. Our results suggest that the surface charge density remains finite and does not vanish, and even grows, as the depletion front propagates through the channel.

  19. Pigments in Thermophilic fungi

    OpenAIRE

    Somasundaram, T; Rao, Sanjay SR; Maheshwari, R

    1986-01-01

    UV and visible absorption spectra of thermophilic fungi were obtained by photoacoustic spectroscopy. Based on these data as well as on the chem. properties and IR spectra, it is suggested that the pigments may be hydroxylated polycyclic quinones.

  20. Chlorophyll: The wonder pigment

    Digital Repository Service at National Institute of Oceanography (India)

    Bhat, S.R.

    Chlorophyll, the green plant pigment, a 'real life force' of living beings, besides synthesizing food, is a great source of vitamins, minerals and other phytochemicals. Adding chlorophyll rich food to our diet fortifies our body against health...

  1. Application of Full Factorial Experimental Design and Response Surface Methodology for Chromite Beneficiation by Knelson Concentrator

    Directory of Open Access Journals (Sweden)

    Gul Akar Sen

    2016-01-01

    Full Text Available The present work is undertaken to determine the effect of operational variables, namely: feed rate, centrifugal force and fluidization water flow rate on the efficiency of Knelson concentrator for chromite ore beneficiation. A full factorial design with three factors at three levels and response surface methodology (RSM were applied for this purpose. The quadratic models were developed to predict the concentrate Cr2O3 grade and recovery as the process responses. The results suggest that all the variables affect the grade and recovery of the Cr2O3 concentrate to some degree. However, the fluidization water rate was found as the most effective parameter.

  2. Polycyclic aromatic hydrocarbons in urban street dust and surface soil: comparisons of concentration, profile, and source.

    Science.gov (United States)

    Wang, De-Gao; Yang, Meng; Jia, Hong-Liang; Zhou, Lei; Li, Yi-Fan

    2009-02-01

    Street dust and surface soil samples in urban areas of Dalian, a coastal city in Liaoning Province, China, were collected and analyzed for 25 polycyclic aromatic hydrocarbons (PAHs). The concentrations, distribution, and sources of PAHs in dust and soil were determined. The concentrations of total PAHs in street dust ranged between 1890 and 17,070 ng/g (dry weight), with an average of 7460 ng/g, whereas the concentrations of total PAHs in surface soil varied greatly, from 650 to 28,900 ng/g, with a mean value of 6440 ng/g. Statistical paired t-test confirmed that total PAH concentrations have no significant difference between street dust and surface soil. Mean PAH concentrations in two type samples were much higher at industrial sites than at business/residential or garden sites. PAHs were dominated by higher molecular weight PAH (4- to 6-ring) homologues, which accounted for about 73% and 72% of total PAHs in street dust and surface soil, respectively. Principal component analysis was used in source apportionment of PAHs in dust and soil. Pyrogenic and petrogenic sources contributed 70% and 22.4% of total PAHs in street dusts, and fossil fuel (coal and petroleum) and biomass combustion accounted for 64.4% and 5.6% of total PAHs in pyrogenic sources, respectively. In surface soil, total PAHs were dominated by pyrogenic sources. The diagnostic ratios of benz[a]anthracene/chrysene confirmed that PAHs in street dust and surface soil of a Dalian urban zone might come mostly from the emission of local sources.

  3. Prodigiosin-like pigments.

    Science.gov (United States)

    Gerber, N N

    1975-05-01

    Prodigiosin, the bright red tripyrrole pigment from Serratia marcescens, has also been identified in Pseudomonas magnesiorubra, Vibrio psychroerythrus, and two Gram-negative rod-shaped mesophilic marine bacteria not members of the genus Serratia. Prodigiosin is sometimes bound to proteins; thus, extracts may require acid treatment before isolation of the pigment. Higher homologs of prodigiosin have been detected by mass spectroscopy. A mutant strain of S. marcescens produced nor-prodigiosin, in which the methoxy group of prodigiosin is replaced by a hydroxy group. Another mutant strain produced a blue tetrapyrrole pigment whose structure is a dimer of prodigiosin's rings A and B. Three novel biosynthetic analogs of prodigiosin have been obtained using a colorless mutant which does make rings A and B but not ring C and which can couple rings A and B with some added monopyrroles similar to ring C. The structures of three prodiginine (prodigiosin-like) pigments from streptomyces have been elucidated. All have the methoxytripyrrole aromatic nucleus of prodigiosin and all have an 11 carbon aliphatic side chain attached at carbon 2 of ring C. In two of the pigments the side chain is also linked to another carbon of ring C. The earlier literature about prodiginine pigments from actinomycetes has been interpreted and evaluated in light of the most recent findings. The structure elucidation of six prodiginine pigments from Actinomadurae (Nocardiae) has been completed. Only one, undecylprodiginine, is the same as from a streptomycete. For three of the six pigments, nine carbon side chains are observed and in four of them the side chain is attached to carbon 5 of ring A as well as carbon 2 of ring C so that a large ring is formed which includes the three pyrrole moieties. A section on identification summarized useful methods and presents information with which any known prodiginine pigment can be identified. The final step in the biosynthesis of prodigiosin was known to be

  4. Photosynthetic Pigments in Diatoms

    OpenAIRE

    Kuczynska, Paulina; Jemiola-Rzeminska, Malgorzata; Strzalka, Kazimierz

    2015-01-01

    Photosynthetic pigments are bioactive compounds of great importance for the food, cosmetic, and pharmaceutical industries. They are not only responsible for capturing solar energy to carry out photosynthesis, but also play a role in photoprotective processes and display antioxidant activity, all of which contribute to effective biomass and oxygen production. Diatoms are organisms of a distinct pigment composition, substantially different from that present in plants. Apart from light-harvestin...

  5. Effects of contact time and concentration on bactericidal efficacy of 3 disinfectants on hard nonporous surfaces.

    Science.gov (United States)

    Hong, Yingying; Teska, Peter J; Oliver, Haley F

    2017-11-01

    This study investigated the influence of contact time and concentration on bactericidal efficacy of 3 types of disinfectants (accelerated hydrogen peroxide [AHP], quaternary ammonium compounds [Quats], and sodium hypochlorite) on stainless steel surfaces using Environmental Protection Agency procedure MB-25-02. We found that bactericidal efficacy was not reduced at contact times or concentrations immediate lower than label use values, but all 3 disinfectants were significantly less bactericidal at significantly lower than label use contact times and concentrations. Overall, the bactericidal efficacy of the sodium hypochlorite disinfectant was most tolerant to the decreases of contact times and concentrations, followed closely by AHP disinfectant, and Quat disinfectant was most affected by contact time and concentration. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  6. Quantitative analysis of pigment dispersion taking into account the full agglomerate size distribution

    OpenAIRE

    Kiil, Søren

    2017-01-01

    This work concerns the development of simulation tools for mapping of pigment dispersion. Focus has been on the mechanical breakage of pigment agglomerates. The underlying physical mechanism was assumed to be surface erosion of spherical pigment agglomerates, and the full agglomerate particle size distribution was simulated. Data from previous experimental investigations with organic pigments were used for model validation.When the linear rate of agglomerate surface erosion was taken to be pr...

  7. Photosynthetic Pigments in Diatoms

    Directory of Open Access Journals (Sweden)

    Paulina Kuczynska

    2015-09-01

    Full Text Available Photosynthetic pigments are bioactive compounds of great importance for the food, cosmetic, and pharmaceutical industries. They are not only responsible for capturing solar energy to carry out photosynthesis, but also play a role in photoprotective processes and display antioxidant activity, all of which contribute to effective biomass and oxygen production. Diatoms are organisms of a distinct pigment composition, substantially different from that present in plants. Apart from light-harvesting pigments such as chlorophyll a, chlorophyll c, and fucoxanthin, there is a group of photoprotective carotenoids which includes β-carotene and the xanthophylls, diatoxanthin, diadinoxanthin, violaxanthin, antheraxanthin, and zeaxanthin, which are engaged in the xanthophyll cycle. Additionally, some intermediate products of biosynthetic pathways have been identified in diatoms as well as unusual pigments, e.g., marennine. Marine algae have become widely recognized as a source of unique bioactive compounds for potential industrial, pharmaceutical, and medical applications. In this review, we summarize current knowledge on diatom photosynthetic pigments complemented by some new insights regarding their physico-chemical properties, biological role, and biosynthetic pathways, as well as the regulation of pigment level in the cell, methods of purification, and significance in industries.

  8. Photosynthetic Pigments in Diatoms

    Science.gov (United States)

    Kuczynska, Paulina; Jemiola-Rzeminska, Malgorzata; Strzalka, Kazimierz

    2015-01-01

    Photosynthetic pigments are bioactive compounds of great importance for the food, cosmetic, and pharmaceutical industries. They are not only responsible for capturing solar energy to carry out photosynthesis, but also play a role in photoprotective processes and display antioxidant activity, all of which contribute to effective biomass and oxygen production. Diatoms are organisms of a distinct pigment composition, substantially different from that present in plants. Apart from light-harvesting pigments such as chlorophyll a, chlorophyll c, and fucoxanthin, there is a group of photoprotective carotenoids which includes β-carotene and the xanthophylls, diatoxanthin, diadinoxanthin, violaxanthin, antheraxanthin, and zeaxanthin, which are engaged in the xanthophyll cycle. Additionally, some intermediate products of biosynthetic pathways have been identified in diatoms as well as unusual pigments, e.g., marennine. Marine algae have become widely recognized as a source of unique bioactive compounds for potential industrial, pharmaceutical, and medical applications. In this review, we summarize current knowledge on diatom photosynthetic pigments complemented by some new insights regarding their physico-chemical properties, biological role, and biosynthetic pathways, as well as the regulation of pigment level in the cell, methods of purification, and significance in industries. PMID:26389924

  9. Photosynthetic Pigments in Diatoms.

    Science.gov (United States)

    Kuczynska, Paulina; Jemiola-Rzeminska, Malgorzata; Strzalka, Kazimierz

    2015-09-16

    Photosynthetic pigments are bioactive compounds of great importance for the food, cosmetic, and pharmaceutical industries. They are not only responsible for capturing solar energy to carry out photosynthesis, but also play a role in photoprotective processes and display antioxidant activity, all of which contribute to effective biomass and oxygen production. Diatoms are organisms of a distinct pigment composition, substantially different from that present in plants. Apart from light-harvesting pigments such as chlorophyll a, chlorophyll c, and fucoxanthin, there is a group of photoprotective carotenoids which includes β-carotene and the xanthophylls, diatoxanthin, diadinoxanthin, violaxanthin, antheraxanthin, and zeaxanthin, which are engaged in the xanthophyll cycle. Additionally, some intermediate products of biosynthetic pathways have been identified in diatoms as well as unusual pigments, e.g., marennine. Marine algae have become widely recognized as a source of unique bioactive compounds for potential industrial, pharmaceutical, and medical applications. In this review, we summarize current knowledge on diatom photosynthetic pigments complemented by some new insights regarding their physico-chemical properties, biological role, and biosynthetic pathways, as well as the regulation of pigment level in the cell, methods of purification, and significance in industries.

  10. Surface concentration nonuniformities resulting from chronoamperometry of a reversible reaction at an ultramicrodisk electrode

    DEFF Research Database (Denmark)

    Britz, Dieter H.; Strutwolf, Jörg

    2016-01-01

    The chronoamperometric experiment at a disk electrode was simulated, assuming a reversible reaction. When the diffusion coefficients of the two substances involved are different, there appears a surface concentration non- uniformity in the radial direction, exhibiting a maximum effect in time...

  11. Nocturnal intermittency in surface CO2 concentrations in sub-Saharan Africa

    Science.gov (United States)

    Data obtained over four adjacent fields of differing management practices in Zimbabwe illustrate the role of atmospheric intermittency as a mechanism for transferring CO2 between the surface and the atmosphere above. At night, limited atmospheric mixing permits CO2 concentrations to increase to leve...

  12. Experimental Measurements of Concentration Fluctuations and Scales in a Dispersing Plume in the Atmospheric Surface Layer Obtained Using a Very Fast Response Concentration Detector

    Science.gov (United States)

    2016-06-14

    VOLUME 33 Experimental Measurements of Concentration Fluctuations and Scales in a Dispersing Plume in the Atmospheric Surface Layer Obtained Using a...Very Fast Response Concentration Detector EUGENE YEE Defence Research Establishment Suffield, Medicine Hat, Alberta , Canada R. CHAN AND P. R...various concentration timescales, length scales , and microscales (e.g., Taylor microscale, correlation scale , length scale based on the spectral

  13. Interaction between Vaccinium bracteatum Thunb. leaf pigment and rice proteins.

    Science.gov (United States)

    Wang, Li; Xu, Yuan; Zhou, Sumei; Qian, Haifeng; Zhang, Hui; Qi, Xiguang; Fan, Meihua

    2016-03-01

    In this study, we investigated the interaction of Vaccinium bracteatum Thunb. leaf (VBTL) pigment and rice proteins. In the presence of rice protein, VBTL pigment antioxidant activity and free polyphenol content decreased by 67.19% and 68.11%, respectively, and L(∗) of the protein-pigment complex decreased significantly over time. L(∗) values of albumin, globulin and glutelin during 60-min pigment exposure decreased by 55.00, 57.14, and 54.30%, respectively, indicating that these proteins had bound to the pigment. A significant difference in protein surface hydrophobicity was observed between rice proteins and pigment-protein complexes, indicating that hydrophobic interaction is a major binding mechanism between VBTL pigment and rice proteins. A significant difference in secondary structures between proteins and protein-pigment complexes was also uncovered, indicating that hydrogen bonding may be another mode of interaction between VBTL pigment and rice proteins. Our results indicate that VBTL pigment can stain rice proteins with hydrophobic and hydrogen interactions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Chemical analysis and surface morphology of enamel following ozone application with different concentrations and exposure times

    Directory of Open Access Journals (Sweden)

    Iman I. Elsayad

    2011-04-01

    Full Text Available This study aimed to determine the effect of different ozone concentrations applied with different exposure times on the chemical composition and the surface morphology of enamel. Twenty human mandibular molars were divided into four groups according to ozone concentration and exposure times. Group A received 90 μg of ozone/ml oxygen for 1 min, group B received 90 μg of ozone/ml oxygen for 2 min, group C received 120 μg of ozone/ml oxygen for 1 min and group D received 120 μg of ozone/ml oxygen for 2 min. The ozone source was from a medical ozone generator equipped with a device to adjust the concentration. Buccal surfaces of teeth were tested before and after ozone application so that each tooth served as a control for itself, using Environmental Scanning Electron Microscope (ESEM connected to an Electron Dispersive Analytical X-ray (EDAX. Changes in calcium and phosphorus percentage levels were recorded and the Ca/P ratio was calculated. The values were statistically analyzed using the one-way ANOVA test with a level of significance set at P ⩽ 0.05. No statistical significant difference was found between the control and the tested groups in minerals content or ratio as P > 0.05. ESEM images showed enamel surface roughness with 2 min ozone exposure times. High ozone concentration with prolonged exposure time does not change the chemical composition of enamel. Applying ozone for 2 min alters the surface morphology of enamel causing variable degrees of roughness. Using high ozone concentrations with prolonged exposure times for caries reversal or prevention and for bleaching may be contraindicated if this changes the surface morphology of enamel.

  15. Correlation between sub-micron surface roughness of iron oxide encrustations and trace element concentrations

    International Nuclear Information System (INIS)

    Fischer, Cornelius; Karius, Volker; Luettge, Andreas

    2009-01-01

    Iron oxide encrustations are formed on black slate surfaces during oxidative weathering of iron sulfide and phosphate bearing, organic matter-rich slates. Synchronously, trace elements are released during ongoing weathering. Laser ablation ICP-MS analyses of a weathered and encrusted slate showed that major portions of the V, Cu, As, Mo, Pb, Th, and U reside in the encrustation. Recently a potential relationship between several micrometer to 500 nm surface topography roughness of such encrustations and its uranium concentration was shown. Based on laser scanning microscopy measurements, the present study shows that this interrelation must be expanded to small submicron-sized half-pores with diameters between 100 nm and 500 nm. We demonstrate that the relationship is not limited to topography variations of a single encrustation in the hand-specimen scale. Surface topography and geochemical analyses of iron oxide encrustations from several locations but from the same geochemical environment and with similar weathering history showed that the concentrations of U, P, Cu, and Zn correlate inversely with the surface roughness parameter F. This parameter represents the total surface area and is - in this case - a proxy for the root-mean square surface roughness Rq. This study substantiates the environmental importance that micrometer- to submicrometer topography variations of fluid-rock interfaces govern the trapping of trace elements.

  16. Correlation between sub-micron surface roughness of iron oxide encrustations and trace element concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Cornelius, E-mail: cornelius@rice.edu [Department of Earth Science, MS-126, Rice University, 6100 Main Street, Houston, TX 77005 (United States); Geowissenschaftliches Zentrum der Universitaet Goettingen, Abt. Sedimentologie and Umweltgeologie, Goldschmidtstr. 3, D-37077 Goettingen (Germany); Karius, Volker [Geowissenschaftliches Zentrum der Universitaet Goettingen, Abt. Sedimentologie and Umweltgeologie, Goldschmidtstr. 3, D-37077 Goettingen (Germany); Luettge, Andreas [Department of Earth Science, MS-126, Rice University, 6100 Main Street, Houston, TX 77005 (United States); Department of Chemistry, Rice University, 6100 Main Street, Houston, TX 77005 (United States)

    2009-08-01

    Iron oxide encrustations are formed on black slate surfaces during oxidative weathering of iron sulfide and phosphate bearing, organic matter-rich slates. Synchronously, trace elements are released during ongoing weathering. Laser ablation ICP-MS analyses of a weathered and encrusted slate showed that major portions of the V, Cu, As, Mo, Pb, Th, and U reside in the encrustation. Recently a potential relationship between several micrometer to 500 nm surface topography roughness of such encrustations and its uranium concentration was shown. Based on laser scanning microscopy measurements, the present study shows that this interrelation must be expanded to small submicron-sized half-pores with diameters between 100 nm and 500 nm. We demonstrate that the relationship is not limited to topography variations of a single encrustation in the hand-specimen scale. Surface topography and geochemical analyses of iron oxide encrustations from several locations but from the same geochemical environment and with similar weathering history showed that the concentrations of U, P, Cu, and Zn correlate inversely with the surface roughness parameter F. This parameter represents the total surface area and is - in this case - a proxy for the root-mean square surface roughness Rq. This study substantiates the environmental importance that micrometer- to submicrometer topography variations of fluid-rock interfaces govern the trapping of trace elements.

  17. Skin pigmentation evaluation in broilers fed natural and synthetic pigments.

    Science.gov (United States)

    Castañeda, M P; Hirschler, E M; Sams, A R

    2005-01-01

    Broiler carcass skin color is important in the United States and Mexico. This study evaluated the use of natural and synthetic pigments in broiler diets at commercial levels. Birds were fed natural or synthetic pigments at low or high levels, simulating US and Mexican commercial practices. Skin color was measured during live production (3 to 7 wk of age) and after slaughter and chilling. The natural pigments had consistently greater skin b* values (yellowness) than the synthetic pigments. The high levels produced greater skin b* values than the low levels, regardless of source. The synthetic pigments had a slower increase in skin b* but reached the same level as the natural low by 7 wk. There was no difference in skin a* values (redness) due to pigment source or level or the age of the bird. By 7 wk, all pigment sources approached plateau levels in the blood, but the synthetic pigment diet produced higher blood levels of yellow and red pigments than the natural pigment diets. Processing intensified skin yellowness and reduced skin redness. These data suggest that although synthetic pigments might have been absorbed better than natural ones, natural pigments were more efficient at increasing skin yellowness and there were only small differences between high and low levels for each pigment source. This finding may allow reduction in pigment use and feed cost to achieve the same skin acceptance by the consumer.

  18. Concentrations and geographic distribution of selected organic pollutants in Scottish surface soils

    International Nuclear Information System (INIS)

    Rhind, S.M.; Kyle, C.E.; Kerr, C.; Osprey, M.; Zhang, Z.L.; Duff, E.I.; Lilly, A.; Nolan, A.; Hudson, G.; Towers, W.; Bell, J.; Coull, M.; McKenzie, C.

    2013-01-01

    Concentrations of selected persistent organic pollutants (POPs) representing three chemical classes (polycyclic aromatic hydrocarbons (PAH), polybrominated diphenyl ethers (PBDE) and polychlorinated biphenyls (PCB) and the organic pollutant diethylhexyl phthalate (DEHP), were determined in surface soil samples (0–5 cm) collected at 20 km grid intersects throughout Scotland over a three-year period. Detectable amounts of all chemical classes and most individual congeners were present in all samples. There were no consistent effects of soil or vegetation type, soil carbon content, pH, altitude or distance from centres of population on concentrations which exhibited extreme variation, even in adjacent samples. It is concluded that soil POPs and DEHP concentrations and associated rates of animal and human exposure were highly variable, influenced by multiple, interacting factors, and not clearly related to local sources but possibly related to wet atmospheric deposition and the organic carbon content of the soil. -- Highlights: •Concentrations of selected organic pollutants in Scottish soils were determined. •Concentrations were highly variable. •There were few effects of soil or vegetation type, soil carbon, pH or altitude. •Distance from cities was not an important determinant of concentrations. •Atmospheric deposition and soil organic carbon content may affect concentrations. -- Soil concentrations of anthropogenic persistent organic pollutants are not clearly related to soil type or pH, vegetation, altitude, or distance from pollutant sources

  19. Impact of regional ventilation changes on surface particulate matter concentrations in South Korea

    Science.gov (United States)

    Kim, H. C.; Stein, A. F.; Chai, T.; Ngan, F.; Kim, B. U.; Jin, C. S.; Hong, S. Y.; Park, R.; Son, S. W.; Bae, C.; Bae, M.; Song, C. K.; Kim, S.

    2017-12-01

    The recent increase in surface particulate matter (PM) concentrations in South Korea is intriguing due to its disagreement with current intensive emission reduction efforts. The long-term trend of surface PM concentrations in South Korea declined in the 2000s, but since 2012 its concentrations have tended to increase, resulting in frequent severe haze events in the region. This study demonstrates that the interannual variation of surface PM concentrations in South Korea is not only affected by changes in local or regional emission sources, but also closely linked with the interannual variations in regional ventilation. Using EPA Community Multiscale Air Quality modeling system, a 12-year (2004-2015) regional air quality simulation was conducted to assess the impact of the meteorological conditions under constant anthropogenic emissions. In addition, NOAA HYSPLIT dispersion model was utilized to estimate the strength of regional ventilation that dissipates local pollutions. Simulated PM concentrations show a strong negative correlation (i.e. R=-0.86) with regional wind speed, implying that reduced regional ventilation is likely associated with more stagnant conditions that cause severe pollutant episodes in South Korea. We conclude that the current PM concentration trend in South Korea is a combination of long-term decline by emission control efforts and short-term fluctuations in regional wind speed interannual variability. When the meteorology-driven variations are removed, PM concentrations in South Korea have declined continuously even after 2012, with -1.45±0.12, -1.41±0.16, and -1.09±0.16 mg/m3 per year in Seoul, the Seoul Metropolitan Area, and South Korea, respectively.

  20. Effect of temperature and concentration on the surface tension of chia seed mucilage

    Science.gov (United States)

    Fu, Yuting; Arye, Gilboa

    2017-04-01

    The production of mucilage by the seed coat during hydration is a common adaptation of many different plant species. The mucilage may play many ecological roles in adaptation and seed germination in diverse environments, especially in extreme desert conditions. The major compound of the seed mucilage is polysaccharides (e.g. pectins and hemicelluloses), which makes it highly hydrophilic. Consequently, it can hydrate quickly in the presence of water; forming a gel like coating surrounding the seed. However, the seed mucilage also reported to contain small amounts of protein and lipid which may exhibit surface activity at the water-air interface. As a result, decay in the surface tension of water can be occur and consequently a reduction in soil capillary pressure. This in turn may affect the water retention and transport during seed germination. The physical properties of the seeds mucilage have been studied mainly in conjunction with its rheological properties. To the best of our knowledge, its surface activity at the water-air interface has been reported mainly in the realms of food engineering, using a robust method of extraction. The main objective of this study was to quantify the effect of temperature and concentration on the surface tension of seed mucilage. The mucilage in this study was extracted from chia (Salvia hispanica L.) seeds, using distilled water (1:20 w/w) by shaking for 12 h at 4°C. The extracts were freeze dried after centrifuge (5000rpm for 20min). Fresh samples of different concentrations, ranging from 0.5 to 6 mg/ml, were prepared before each surface tension measurements. The equilibrium surface tension was measured by the Wilhelmy plate method using a tensiometer (DCAT 11, Data Physics) with temperature control unit. For a given mucilage concentration, surface tension measurements carried out at 5, 15, 25, 35, 45 °C. The quantitative and thermodynamic analysis of the results will be presented and discussed.

  1. Differences in surface roughness of nanohybrid composites immersed in varying concentrations of citric acid

    Directory of Open Access Journals (Sweden)

    Gabriela Kevina Alifen

    2017-06-01

    Full Text Available Background: The surface roughness of restoration is important in predicting the length of time it might remain in the mouth. Conditions within the oral cavity can affect the surface roughness of a restoration. Nanohybrid composite is widely used in dentistry because it can be applied to restore anterior and posterior teeth. Athletes routinely consume isotonic drinks which are acidic and even more erosive than the carbonated variety because they contain a range of acids; the highest content of which being citric acid. Purpose: The aim of the study was to analyze the surface roughness of nanohybrid composite after having been subjected to immersion in varying concentrations of citric acid. Methods: Two isotonic drinks (Pocari Sweat and Mizone were analyzed using high performance liquid chromatography (HPLC to quantify the respective concentrations of citric acid which they contained. A total of 27 samples of cylindrical nanohybrid composite were prepared before being divided into three groups. In Group 1, samples were immersed in citric acid solution derived from Pocari Sweat. Those of Group 2 were immersed in citric acid solution derived from Mizone; while Group 3, samples were immersed in distilled water as a control. All samples were immersed for 7 days, before their surface roughness was tested by means of a surface roughness tester (Mitutoyo SJ-201. Data was analyzed using a one-way ANOVA test. Results: The results showed that there was no significant difference in surface roughness between Groups 1, 2 and 3 (p=0.985. Conclusion: No difference in surface roughness of nanohybrid composites results from prolonged immersion in varying concentrations of citric acid.

  2. Seasonal and interannual variations in pigments in the Adriatic Sea

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    which lead to the higher chlorophyll production can be advected in the surface layer, together with dissolved colored substances, carried by the runoff, where both can increase pigment concentra- tions. This can explain relatively higher pigment in August in the Middle Adriatic. The influence of the Northern Italian waters ...

  3. Galvanic displacement synthesis of Al/Ni core–shell pigments and their low infrared emissivity application

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Le, E-mail: yuanle.cn@gmail.com [Center for Advanced Materials and Energy, Xihua University, Chengdu, 610039 (China); National Engineering Research Center of Electromagnetic Radiation Control Materials, UESTC, Chengdu, 610054 (China); Hu, Juan [Center for Advanced Materials and Energy, Xihua University, Chengdu, 610039 (China); Weng, Xiaolong [National Engineering Research Center of Electromagnetic Radiation Control Materials, UESTC, Chengdu, 610054 (China); Zhang, Qingyong [Center for Advanced Materials and Energy, Xihua University, Chengdu, 610039 (China); Deng, Longjiang [National Engineering Research Center of Electromagnetic Radiation Control Materials, UESTC, Chengdu, 610054 (China)

    2016-06-15

    We have successfully developed a magnetic Al/Ni core–shell pigment via a galvanic displacement reaction to obtain low infrared emissivity pigment with low lightness and visible light reflectance. Al/Ni core–shell particles were prepared via a simple one-step synthetic method where Ni was deposited onto the Al surface at the expense of Al atoms. The influence of pH and the amount of NH{sub 4}F complexing agent on phase structure, surface morphology, optical and magnetic properties were studied systematically. The neutral condition and high concentration of NH{sub 4}F forms smooth, flat, uniform and dense Ni shell on the surface of flake Al particles, which can significantly reduce the lightness and visible light reflectance but slightly increase the infrared emissivity. When the core–shell pigments are prepared in neutral pH solution at NH{sub 4}F = 11.2 g/L, the lightness (L{sup *}) and visual light reflectivity can be reduced by 12.6 and 0.46, respectively versus uncoated flake Al pigments, but the infrared emissivity is only increased by 0.02. The color changes from brilliant silver to gray black and the saturation magnetization value is 6.59 emu/g. Therefore, these Al/Ni magnetic composite pigments can be used as a novel low infrared emissivity pigment to improve the multispectral stealth performance of low-E coatings in the visual, IR and Radar wavebands. - Highlights: • Prepared magnetic Al/Ni core–shell pigment with low lightness and low emissivity. • Used one-pot galvanic displacement reaction to form smooth and dense Ni shell. • Show enhanced stealth performance in the visual, IR and Radar wavebands. • The lightness and visible light reflectance was decreased by 12.6 and 0.46. • But the infrared emissivity was only increases by 0.02.

  4. [The correlation between the concentrations of VEGF and PEDF and Ca2+-PKC signaling pathways in human retinal pigment epithelial cells cultured in vitro after exposuring to blue light].

    Science.gov (United States)

    Wang, Limin; Cai, Shanjun; Wu, Zhipeng; Gong, Xin; Lyu, Jianping; Su, Gang; Wang, Lili

    2015-11-01

    To investigate the concentrations of vascular endothelial growth factor (VEGF), pigment epithelium-derived factor (PEDF), inositol triphosphate (IP3) and diacylglycerol (DAG) in human retinal pigment epithelium (RPE) cells after exposuring to blue light, and to explore the relationship with Ca2+-PKC signaling pathways, to evaluate the role of Ca2+-PKC signaling pathways of blue-light irradiation induced apoptosis in RPE cells. The fourth generation human RPE cells in vitro were exposured to blue light (2000±500 lux) for 6 hours, 24 hours prolongation of post-exposure culture. The concentrations of VEGF, PEDF, IP3 and DAG were assayed by enzyme linked immunosorbent assay (ELISA). Cells were randomly divided into 6 groups, group A (control), group B (exposure to blue light), group C (exposure to blue light+PMA), group D (exposure to blue light+Calphostin C), group E (exposure to blue light+Nifedipine), group F (exposure to blue light+Calphostin C+Nifedipine). Flow cytometry was used to detect the apoptosis rate of human RPE cells in A, B and F group. Comparing with group A (584.38±10.66), the concentration of VEGF in group B (700.70±5.88), group C (698.21±6.66) and group E (648.30±4.91) was higher, the difference was statistically significant (P=0.002, 0.002, 0.016). Comparing with group B (700.70±5.88), the concentration of VEGF in Group D (623.87±3.12) and E (648.30±4.91) was lower (P=0.001, 0.002). Comparing with group A (75.96±1.70), the concentration of PEDF in Group B (71.82±1.67) and C (72.43±0.58) was lower (P=0.004, 0.011), but the concentration of PEDF in Group D (86.31±1.35) and E (93.72±1.24) was higher (P=0.000, 0.000). Comparing with group B (71.82±1.67), the concentration of PEDF in Group D (86.31±1.35) and E (93.72±1.24) was higher (P=0.000, 0.000). Comparing with group A (7.70±0.29), the ratio of VEGF to PEDF in Group B (9.85±0.34) and Croup C (9.64±0.02) was higher (P=0.008, 0.027) Comparing with group B, The ratio of VEGF to PEDF

  5. Muscle conduction velocity, surface electromyography variables, and echo intensity during concentric and eccentric fatigue.

    Science.gov (United States)

    Gonzalez-Izal, Miriam; Lusa Cadore, Eduardo; Izquierdo, Mikel

    2014-03-01

    Concentric (CON) and eccentric (ECC) contractions may involve different mechanisms related to changes in sarcolemma status and the consequent alteration of action potential transmission along muscle fibers. Muscle conduction velocity (CV), surface electromyography signal (sEMG), muscle quality, and blood lactate concentrations were analyzed during CON and ECC actions. Compared with ECC, the CON protocol resulted in greater muscle force losses, blood lactate concentrations, and changes in sEMG parameters. Similar reductions in CV were detected in both protocols. Higher echo intensity values were observed 2 days after ECC due to greater muscle damage. The effects of the muscle damage produced by ECC exercise on the transmission of action potentials along muscle fibers (measured as the CV) may be comparable with the effects of hydrogen accumulation produced by CON exercise (related to greater lactate concentrations), which causes greater force loss and change in other sEMG variables during CON than during ECC actions.

  6. The influence of surface roughness and solution concentration on pool boiling process in Diethanolamine aqueous solution

    Science.gov (United States)

    Khoshechin, Mohsen; Salimi, Farhad; Jahangiri, Alireza

    2018-04-01

    In this research, the effect of surface roughness and concentration of solution on bubble departing frequency and nucleation site density for pool boiling of water/diethanolamine (DEA) binary solution were investigated experimentally. In this investigation, boiling heat transfer coefficient, bubble departing frequency and nucleation site density have been experimentally investigated in various concentrations and heat fluxes. Microstructured surfaces with a wide range of well-defined surface roughness were fabricated, and a heat flux between 1.5-86 kW/m2 was achieved under atmospheric conditions. The Results indicated that surface roughness and concentration of solution increase the bubble departing frequency and nucleation site density with increasing heat flux. The boiling heat transfer coefficient in mixtures of water/DEA increases with increasing concentration of DEA in water. The experimental results were compared with predictions of several used correlations in the literatures. Results showed that the boiling heat transfer coefficients of this case study are much higher than the predicted values by major existing correlations and models. The excellent agreement for bubble departing frequency found between the models of Jackob and Fritz (1966) and experimental data and also the nucleation site density were in close agreement with the model of Paul (1983) data. f bubble departure frequency, 1/s or Hz N Number of nucleation sites per area per time R c Minimum cavity size, m D c critical diameter, m g gravitational acceleration, m/s2 ρ density, kg/m3 T temperature, °c ΔT temperature difference, °c d d vapor bubble diameter, m h fg enthalpy of vaporization, J/kg R Roughness, μm Ja Jakob number cp specific heat, J/kg °c Pr Prandtl number Ar Archimedes number h Heat transfer coefficient, J/(m2 °c) tg time it takes to grow a bubble, s q/A heat flux (kW/m2) tw time required to heat the layer, s gc Correction coefficient of incompatible units R a Surface

  7. Pickering emulsions stabilized by coloured organic pigment particles† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c6sc03085h Click here for additional data file.

    Science.gov (United States)

    Olusanya, Samuel O.

    2017-01-01

    The possibility of stabilizing emulsions of water and non-polar alkane with pure, coloured organic pigment particles is explored. Seven pigment types each possessing a primary colour of the rainbow were selected. Their solubility in water or heptane was determined using a spectrophotometric method and their surface energies were derived from the contact angles of probe liquids on compressed disks of the particles. As expected, most of the pigments are relatively hydrophobic but pigment orange is quite hydrophilic. At equal volumes of oil and water, preferred emulsions were water-in-oil (w/o) for six pigment types and oil-in-water (o/w) for pigment orange. The emulsion type is in line with calculated contact angles of the particles at the oil–water interface being either side of 90°. Their stability to coalescence increases with particle concentration. Emulsions are shown to undergo limited coalescence from which the coverage of drop interfaces by particles has been determined. In a few cases, close-packed primary particles are visible around emulsion droplets. At constant particle concentration, the influence of the volume fraction of water (φ w) on emulsions was also studied. For the most hydrophilic pigment orange, emulsions are o/w at all φ w, whereas they are w/o for the most hydrophobic pigments (red, yellow, green and blue). For pigments of intermediate hydrophobicity however (indigo and violet), catastrophic phase inversion becomes possible with emulsions inverting from w/o to o/w upon increasing φ w. For the first time, we link the pigment surface energy to the propensity of emulsions to phase invert transitionally or catastrophically. PMID:28626551

  8. Modification of sea surface temperature by chlorophyll concentration in the Atlantic upwelling systems

    Science.gov (United States)

    Hernandez, O.; Jouanno, J.; Echevin, V.; Aumont, O.

    2017-07-01

    The influence of the chlorophyll on the upper Tropical Atlantic Ocean is investigated with long-term (1979-2012) regional oceanic simulations with 1/4° horizontal resolution based on the NEMO3.6 model. The model solar radiation penetration scheme depends on the chlorophyll concentration. Simulations with time and spatially varying concentrations obtained from satellite ocean color observations are compared with a simulation forced with constant chlorophyll concentration of 0.05 mg m-3, representative of chlorophyll depleted waters. Results indicate that regions of the Tropical Atlantic with chlorophyll concentrations larger than in the reference simulation (i.e., [chl] > 0.05 mg m-3) get warmer at the surface, with the exception of the main upwelling regions where high chlorophyll concentrations are associated with a significant cooling of the sea surface (˜1°C in the Benguela upwelling). The analysis of the model heat balance shows that the biological differential heating causes negative temperature anomalies in subsurface source waters prior to their upwelling at the coast. The shallow mixed-layer in the eastern equatorial and tropical Atlantic favors the persistence of these subsurface anomalies and may explain why the Benguela is particularly sensitive to the biological differential heating. In spite of the presence of high chlorophyll concentrations in the upwelling regions, both the larger amount of shortwave radiation captured in the surface layers and the modifications of the horizontal and vertical advection at the coast are found to play a secondary role in the SST change in the upwelling region.

  9. Chlorophyll modulation of sea surface temperature in the Arabian Sea in a mixed-layer isopycnal general circulation model

    Digital Repository Service at National Institute of Oceanography (India)

    Nakamoto, S.; PrasannaKumar, S.; Muneyama, K.; Frouin, R.

    Remotely sensed chlorophyll pigment concentrations from the Coastal Zone Color Scanner (CZCS) are used to estimate biological heating rate and investigate the biological modulation of the sea surface temperature (SST) in a bulk mixed layer model...

  10. The effect of some soil characteristics on soil radon concentration and radon exhalation from soil surface

    International Nuclear Information System (INIS)

    Sun, Kainan; Cheng, Jianping; Guo, Qiuju

    2004-01-01

    To find out the impacts of soil characters on radon concentration in soil and radon exhalation from soil, field measurements on soil radon concentrations (60 cm under the soil surface) and radon exhalation rate from soil surface were carried out in totally 31 points with different types of soil in three cities in both South and North China. Soil radium contents, water contents, soil porosity and grain size were concretely analyzed in our laboratory. The linear simulation was used to analyze the above data. The results showed that radon exhalation rate from soil and radon concentrations in soil have direct proportion to soil radium contents. Rather high radium content and radon exhalation rate were measured in Guiyang area, 67±28Bq/Kg and 40±59 mBq/m 2 ·s, however no high soil radon concentration was found due to the difficulties in the measurements on clay soils with high saturation. Compared with soil radium contents, radon exhalation rate from soil and soil radon concentrations are more easily impacted by soil characters and change in a rather large range. (author)

  11. Production of Monascus-like pigments

    DEFF Research Database (Denmark)

    2012-01-01

    The present invention relates to a method for producing one or more Monascus-like pigment composition from Penicillium species comprising: a) providing a cultivation medium comprising a high concentration of C-and N-sources and a high C/N molar ratio, b) adjusting pH to about 5 to 8, c) inoculati...

  12. Predicting hair cortisol levels with hair pigmentation genes: A possible hair pigmentation bias

    NARCIS (Netherlands)

    Neumann, A. (Alexander); G. Noppe (Gerard); F. Liu; M.H. Kayser (Manfred); F.C. Verhulst (Frank); V.W.V. Jaddoe (Vincent); E.F.C. van Rossum (Liesbeth); H.W. Tiemeier (Henning)

    2017-01-01

    textabstractCortisol concentrations in hair are used to create hormone profiles spanning months. This method allows assessment of chronic cortisol exposure, but might be biased by hair pigmentation: dark hair was previously related to higher concentrations. It is unclear whether this association

  13. Betalain: a particular class of antioxidant pigment.

    Science.gov (United States)

    El Gharras, Hasna

    2011-10-01

    We have analyzed the stability of betalains in juices prepared from Moroccan yellow cactus pears (Opuntia ficus indica (L.) Mill.) as a function of temperature and pH. The experiments were carried out at temperatures ranging from 80 to 100 degrees C with juices at pH 3.5, 5 and 6.5. The degree of pigment retention decreased when the temperature increased. The degradation constant rates were determined for thermal degradation rates of pseudo-first order. The Arrhenius plot obtained for the degradation of betaxanthin from the yellow fruits was not linear. Regardless of the temperature of treatment, the lowest degradation was obtained for pH 5. When some stabilizers were tested for the protection of pigments, the results showed that ascorbic acid was a better protective agent at pH 3.5, increasing the protection by 40%. The inhibitive action of betalain pigments extracted from cactus pears towards corrosion of stainless steel in phosphoric acid was investigated using electrochemical polarization and electrochemical impedance spectroscopy (EIS) methods. It was found that the presence of natural pigments reduces the corrosion rate of the tested metal, especially on addition of the red pigments (97%). The inhibition efficiency increases as the pigment concentration of extracts increases. It was also found that the pigments tested act as mixed inhibitors. The inhibitive action of the extracts is discussed in term of adsorption and that such adsorption follows a Langmuir adsorption isotherm. The calculated values of the free energy of adsorption indicated that the adsorption process is spontaneous.

  14. RISK ASSESSMENT FOR THE DYE AND PIGMENT ...

    Science.gov (United States)

    This risk assessment calculates the maximum loadings of constituents found in dyes and pigment industries waste streams which can be disposed in different types of waste management units without causing health benchmarks to be exceeded at plausible receptor locations. The assessment focuses on potential risks from volatilization and leaching to groundwater of constituents disposed in surface impoundments and landfills with either clay liners or composite liners. This product will be used by EPA decision makers to assist in determining whether certain waste streams generated by the dyes and pigments industries should be designated as hazardous.

  15. Raman af hvide pigmenter

    DEFF Research Database (Denmark)

    Reeler, Nini Elisabeth Abildgaard; Nielsen, Ole Faurskov; Sauer, Stephan P. A.

    2013-01-01

    Et samspil mellem kunst og kemi. I et samarbejde mellem Statens Museum for Kunst og Kemisk Institut på KU er Ramanspek-troskopi brugt til at definere sammensætningen af blandinger af blyhvidt og calcit i maleriers hvide pigmenter.......Et samspil mellem kunst og kemi. I et samarbejde mellem Statens Museum for Kunst og Kemisk Institut på KU er Ramanspek-troskopi brugt til at definere sammensætningen af blandinger af blyhvidt og calcit i maleriers hvide pigmenter....

  16. Probabilistic risk assessment of insecticide concentrations in agricultural surface waters: a critical appraisal.

    Science.gov (United States)

    Stehle, Sebastian; Knäbel, Anja; Schulz, Ralf

    2013-08-01

    Due to the specific modes of action and application patterns of agricultural insecticides, the insecticide exposure of agricultural surface waters is characterized by infrequent and short-term insecticide concentration peaks of high ecotoxicological relevance with implications for both monitoring and risk assessment. Here, we apply several fixed-interval strategies and an event-based sampling strategy to two generalized and two realistic insecticide exposure patterns for typical agricultural streams derived from FOCUS exposure modeling using Monte Carlo simulations. Sampling based on regular intervals was found to be inadequate for the detection of transient insecticide concentrations, whereas event-triggered sampling successfully detected all exposure incidences at substantially lower analytical costs. Our study proves that probabilistic risk assessment (PRA) concepts in their present forms are not appropriate for a thorough evaluation of insecticide exposure. Despite claims that the PRA approach uses all available data to assess exposure and enhances risk assessment realism, we demonstrate that this concept is severely biased by the amount of insecticide concentrations below detection limits and therefore by the sampling designs. Moreover, actual insecticide exposure is of almost no relevance for PRA threshold level exceedance frequencies and consequential risk assessment outcomes. Therefore, we propose a concept that features a field-relevant ecological risk analysis of agricultural insecticide surface water exposure. Our study quantifies for the first time the environmental and economic consequences of inappropriate monitoring and risk assessment concepts used for the evaluation of short-term peak surface water pollutants such as insecticides.

  17. Spatial Gradients in Trace Metal Concentrations in the Surface Microlayer of the Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    Antonio eTovar-Sanchez

    2014-12-01

    Full Text Available The relationship between dust deposition and surface water metal concentrations is poorly understood. Dissolution, solubility, and partitioning reactions of trace metals from dust particles are governed by complex chemical, biological, and physical processes occurring in the surface ocean. Despite that, the role of the sea surface microlayer (SML, a thin, but fundamental component modulating the air-sea exchange of materials has not been properly evaluated. Our study revealed that the SML of the Mediterranean Sea is enriched with bioactive trace metals (i.e., Cd, Co, Cu and Fe, ranging from 8 (for Cd to 1000 (for Fe times higher than the dissolved metal pool in the underlying water column. The highest enrichments were spatially correlated with the atmospheric deposition of mineral particles. Our mass balance results suggest that the SML in the Mediterranean Sea contains about 2 tonnes of Fe. However, we did not detect any trends between the concentrations of metals in SML with the subsurface water concentrations and biomass distributions. These findings suggest that future studies are needed to quantify the rate of metal exchange between the SML and the bioavailable pool and that the SML should be considered to better understand the effect of atmospheric inputs on the biogeochemistry of trace metals in the ocean.

  18. Impact of Donor Age, Gender and Handling Time on the DNA Concentration Left on Different Surfaces

    Directory of Open Access Journals (Sweden)

    Branka Gršković

    2014-09-01

    Full Text Available Background: We analyzed the correlation between several factors (donor age and gender, and handling time and trace DNA concentration that participants left on different surfaces (paper, plastic, plastic coated metal while holding items in their hands or rubbing them with their fingers, their palms, and the side of the palm of the dominant hand. Material and Methods: Sixty participants took part in the study. Items were swabbed with a moistened cotton swab. DNA was isolated using the Chelex procedure and quantified by real-time PCR. Results: We found that DNA concentration transferred to an item was independent of the handling time. On the contrary, it was dependent on the item’s texture; the greatest concentration was left on plastic coated metal (PCM and the least on paper. The greatest concentration of trace DNA was left by participants from 35 to 44 years of age. Results of the study showed that men deposit a higher DNA concentration than do women. Conclusion: Item texture, donor age, and gender influence trace DNA concentration. Further investigations are necessary to fully understand the process of DNA transfer from donors to handled items.

  19. Concentration Dependences of the Surface Tension and Density of Solutions of Acetone-Ethanol-Water Systems at 293 K

    Science.gov (United States)

    Dadashev, R. Kh.; Dzhambulatov, R. S.; Mezhidov, V. Kh.; Elimkhanov, D. Z.

    2018-05-01

    Concentration dependences of the surface tension and density of solutions of three-component acetone-ethanol-water systems and the bounding binary systems at 273 K are studied. The molar volume, adsorption, and composition of surface layers are calculated. Experimental data and calculations show that three-component solutions are close to ideal ones. The surface tensions of these solutions are calculated using semi-empirical and theoretical equations. Theoretical equations qualitatively convey the concentration dependence of surface tension. A semi-empirical method based on the Köhler equation allows us to predict the concentration dependence of surface tension within the experimental error.

  20. Platelet-Rich Plasma Increases Pigmentation.

    Science.gov (United States)

    Uysal, Cagri A; Ertas, Nilgun Markal

    2017-11-01

    Platelet-rich plasma (PRP) is an autologous solution of plasma containing 4 to 7 times the baseline concentration of human platelets. Platelet-rich plasma has been widely popular in facial rejuvenation to attenuate wrinkles and has been practically used. The authors have been encountering various patients of increased hiperpigmentation following PRP applications that were performed to attenuate the postinflammatory hiperpigmentation especially after laser treatment. The authors have been using PRP for facial rejuvenation in selected patients and in 1 patient the authors have encountered increased pigmentation over the pigmented skin lesions that were present before the application. The authors recommend that the PRP might increase pigmentation especially in the face region and precautions might be taken before and after the application. Platelet-rich plasma should not be used for the treatment of post inflammatory hiperpigmentation.

  1. Efeito do estresse salino sobre a concentração de pigmentos e prolina em folhas de arroz Effect of salt stress on pigments and proline concentrations in leaves of rice

    Directory of Open Access Journals (Sweden)

    Maria da Graça de Souza Lima

    2004-12-01

    Full Text Available O experimento foi desenvolvido em casa de vegetação com as cultivares BRS Bojurú, IAS 12-9 Formosa e BRS Agrisul, a fim de analisar o efeito da concentração de NaCl (0, 25, 50, 75 e 100 mM nos teores de clorofilas, carotenóides totais e de prolina, determinados a 30 dias após salinização do solo. A salinidade reduziu fortemente o teor de clorofilas e carotenóides totais no genótipo Agrisul, mas esses pigmentos não foram afetados no Bojurú e Formosa pela concentração salina. O teor de prolina foi maior na cultivar Agrisul do que nas cultivares Bojurú e Formosa e acentuou-se com o incremento na concentração de NaCl. Foi verificada uma concentração salina limiar que inicia o processo de acúmulo de prolina nas folhas, sendo de 50 mM para a cultivar BRS Agrisul (sensível e de 75 mM para BRS Bojurú e IAS 12-9 Formosa (tolerantes.In order to analyse the effect of salt (0, 25, 50, 75 and 100 mM concentration on chlorophylls, total carotenoids and proline contents, an experiment was carried out in greenhouse conditions with cultivars BRS Bojurú, IAS 12-9 Formosa and BRS Agrisul. Total contents were determined 30 days after soil salinization. The salinity strongly reduced chlorophylls and total carotenoids contents on Agrisul genotype, but pigments were not quite affected on Bojuru and Formosa. Proline contents were ligher in Agrisul than in the Bujuru and Formosa genotypes, and the proline accumulation was accentuated with increase in salt concentration. A threshhold of salt concentration that starts the process of proline accumulation in leaves was verified, being 50 mM to cultivar BRS Agrisul (sensitive and 75 mM to cultivars BRS Bojuru and IAS 12-9 Formosa (tolerants.

  2. True bursal pigmented villonodular synovitis

    International Nuclear Information System (INIS)

    Abdelwahab, Ibrahim Fikry; Kenan, Samuel; Steiner, German C.; Abdul-Quader, Mohammed

    2002-01-01

    We describe two cases of pigmented villonodular synovitis affecting true bursae. This study was also designed to discuss the term ''pigmented villonodular bursitis'', not confined to true synovial bursae, sometimes creating misunderstanding. (orig.)

  3. True bursal pigmented villonodular synovitis

    Energy Technology Data Exchange (ETDEWEB)

    Abdelwahab, Ibrahim Fikry [Department of Radiology, New York Methodist Hospital, Affiliated with New York Hospital-Cornell Medical Center, Brooklyn, NY (United States); Kenan, Samuel [Department of Orthopedics, New York University Medical Center, NY (United States); Steiner, German C. [Department of Pathology, Hospital for Joint Diseases/Orthopedic Institute, New York, NY (United States); Abdul-Quader, Mohammed [Department of Radiology, New York Presbyterian Hospital, Columbia University, New York, NY (United States)

    2002-06-01

    We describe two cases of pigmented villonodular synovitis affecting true bursae. This study was also designed to discuss the term ''pigmented villonodular bursitis'', not confined to true synovial bursae, sometimes creating misunderstanding. (orig.)

  4. Optimization of artificial neural network models through genetic algorithms for surface ozone concentration forecasting.

    Science.gov (United States)

    Pires, J C M; Gonçalves, B; Azevedo, F G; Carneiro, A P; Rego, N; Assembleia, A J B; Lima, J F B; Silva, P A; Alves, C; Martins, F G

    2012-09-01

    This study proposes three methodologies to define artificial neural network models through genetic algorithms (GAs) to predict the next-day hourly average surface ozone (O(3)) concentrations. GAs were applied to define the activation function in hidden layer and the number of hidden neurons. Two of the methodologies define threshold models, which assume that the behaviour of the dependent variable (O(3) concentrations) changes when it enters in a different regime (two and four regimes were considered in this study). The change from one regime to another depends on a specific value (threshold value) of an explanatory variable (threshold variable), which is also defined by GAs. The predictor variables were the hourly average concentrations of carbon monoxide (CO), nitrogen oxide, nitrogen dioxide (NO(2)), and O(3) (recorded in the previous day at an urban site with traffic influence) and also meteorological data (hourly averages of temperature, solar radiation, relative humidity and wind speed). The study was performed for the period from May to August 2004. Several models were achieved and only the best model of each methodology was analysed. In threshold models, the variables selected by GAs to define the O(3) regimes were temperature, CO and NO(2) concentrations, due to their importance in O(3) chemistry in an urban atmosphere. In the prediction of O(3) concentrations, the threshold model that considers two regimes was the one that fitted the data most efficiently.

  5. Determination of particle concentration rankings by spatial mapping of particle surface area, number, and mass concentrations in a restaurant and a die casting plant.

    Science.gov (United States)

    Park, Ji Young; Ramachandran, Gurumurthy; Raynor, Peter C; Olson, Gregory M

    2010-08-01

    Measurements using several exposure metrics were carried out in a restaurant and a die casting plant to compare the spatial distributions of particle surface area (SA), number, and mass concentrations and rank exposures in different areas by those metrics. The different exposure metrics for incidental nanoparticle and fine particle exposures were compared using the concentration rankings, statistical differences between areas, and concentration ratios between different areas. In the die casting plant, area concentration rankings and spatial distributions differed by the exposure metrics chosen. Surface area and fine particle number concentrations were greatest near incidental nanoparticle sources and were significantly different between three areas. However, mass and coarse particle number concentrations were similar throughout the facility, and rankings of the work areas based on these metrics were different from those of SA and fine number concentrations. In the restaurant, concentrations in the kitchen for all metrics except respirable mass concentration were significantly greater than in the serving area, although SA and fine particle number concentrations showed larger differences between the two areas than either the mass or coarse particle number concentrations. Thus, the choice of appropriate exposure metric has significant implications for exposure groupings in epidemiologic and occupational exposure studies.

  6. Variation in glyphosate and AMPA concentrations of surface water and groundwater

    Science.gov (United States)

    Caprile, Ana Clara; Aparicio, Virginia; Sasal, Carolina; Andriulo, Enrique

    2017-04-01

    The presence of pesticides in various environmental matrices indicate that the soil's ability to function as a bio-physical-chemical reactor is declining. As it operates as an interface between air and water, it causes a negative impact on these two vital resources. Currently, the pampa agriculture is simplified with a marked tendency towards spring-summer crops, where the main crops are RR soybean and corn. Herbicides are neither retained nor degraded in the soil, which results in polluted groundwater and surface waters. The objectives of this study were: a) to verify the presence of glyphosate and aminomethylphosphonic acid (AMPA) in Pergamino stream (a typical representative of the most productive agricultural region of Argentina) under different land use and to detect if in the detections there was a space-time pattern, and b) to verify the detection of these molecules in groundwater of the upper same basin under exclusively rural land use. Surface stream was sampling in six sites (five under rural land use and one under urban-industrial land use) at a rate of one sample by spring, summer and winter seasons (2010-2013, 54 total samples). Groundwater glyphosate and AMPA concentrations were determined in 24 piezometers constructed at two positions of the landscape, across the groundwater flow direction, sampled at two sampling dates (2010 and 2012, 45 total samples). In surface water, glyphosate and AMPA were detected in 54 and 69% of the samples analyzed, respectively. The median concentrations were 0.9 and 0.8 µg L-1 for glyphosate and AMPA and maximal concentrations 258 and 5865 µg L-1, respectively. The sampling site under urban-industrial land use had abnormally high concentrations of glyphosate in the spring (attributed to point pollution), a fact that not allowed to see differences in the remaining sampling times under different land uses. AMPA concentrations under urban-industrial land use were high and higher than rural land use in 3 studied seasons

  7. Phototrophic pigment production with microalgae

    NARCIS (Netherlands)

    Mulders, K.J.M.

    2014-01-01

    Abstract

    Microalgal pigments are regarded as natural alternatives for food colorants. To facilitate optimization of microalgae-based pigment production, this thesis aimed to obtain key insights in the pigment metabolism of phototrophic microalgae, with the main focus on secondary

  8. Phototrophic pigment production with microalgae

    NARCIS (Netherlands)

    Mulders, K.J.M.

    2014-01-01

    Abstract

    Microalgal pigments are regarded as natural alternatives for food colorants. To facilitate optimization of microalgae-based pigment production, this thesis aimed to obtain key insights in the pigment metabolism of phototrophic microalgae, with the main  focus

  9. Quantitative kinetics of proteolytic enzymes determined by a surface concentration-based assay using peptide arrays.

    Science.gov (United States)

    Jung, Se-Hui; Kong, Deok-Hoon; Park, Seoung-Woo; Kim, Young-Myeong; Ha, Kwon-Soo

    2012-08-21

    Peptide arrays have emerged as a key technology for drug discovery, diagnosis, and cell biology. Despite the promise of these arrays, applications of peptide arrays to quantitative analysis of enzyme kinetics have been limited due to the difficulty in obtaining quantitative information of enzymatic reaction products. In this study, we developed a new approach for the quantitative kinetics analysis of proteases using fluorescence-conjugated peptide arrays, a surface concentration-based assay with solid-phase peptide standards using dry-off measurements, and compared it with an applied concentration-based assay. For fabrication of the peptide arrays, substrate peptides of cMMP-3, caspase-3, caspase-9, and calpain-1 were functionalized with TAMRA and cysteine, and were immobilized onto amine-functionalized arrays using a heterobifunctional linker, N-[γ-maleimidobutyloxy]succinimide ester. The proteolytic activities of the four enzymes were quantitatively analyzed by calculating changes induced by enzymatic reactions in the concentrations of peptides bound to array surfaces. In addition, this assay was successfully applied for calculating the Michaelis constant (K(m,surf)) for the four enzymes. Thus, this new assay has a strong potential for use in the quantitative evaluation of proteases, and for drug discovery through kinetics studies including the determination of K(m) and V(max).

  10. Biofunctionalization of the implant surface with different concentrations of a synthetic peptide (P-15).

    Science.gov (United States)

    Lutz, R; Prechtl, C; Nonhoff, J; Weisel, T; Damien, C J; Schlegel, K A

    2013-07-01

    This study aimed at identifying the ideal concentration of a biofunctional surface coating of dental implants with a synthetic peptide (P-15). In a previous study, P-15 was shown to enhance osseointegration parameters. Implants (modified ANKYLOS(®) A8; FRIADENT Plus(®) surface) with five different concentrations (0-400 μg/ml) of a P-15 coating as well as uncoated controls were inserted in the frontal bone of 45 adult domestic pigs. The histomorphometric and microradiographic findings for the coated implants were compared to those for the uncoated ones after 7, 14, and 30 days. No significant differences were observed comparing the peri-implant bone density between the coated and uncoated implants The bone-to-implant contact, as the primary histological parameter for osseointegration, showed high rates for all surfaces investigated (between 73.3 ± 17.9% for the control and 81.9 ± 15.2% for P15 20 μg/ml after 30 days). No significant benefit on osseointegration of a biofunctional P-15 coating of dental implants could be displayed in the present study. © 2012 John Wiley & Sons A/S.

  11. Optimization of sampling for the determination of the mean Radium-226 concentration in surface soil

    International Nuclear Information System (INIS)

    Williams, L.R.; Leggett, R.W.; Espegren, M.L.; Little, C.A.

    1987-08-01

    This report describes a field experiment that identifies an optimal method for determination of compliance with the US Environmental Protection Agency's Ra-226 guidelines for soil. The primary goals were to establish practical levels of accuracy and precision in estimating the mean Ra-226 concentration of surface soil in a small contaminated region; to obtain empirical information on composite vs. individual soil sampling and on random vs. uniformly spaced sampling; and to examine the practicality of using gamma measurements in predicting the average surface radium concentration and in estimating the number of soil samples required to obtain a given level of accuracy and precision. Numerous soil samples were collected on each six sites known to be contaminated with uranium mill tailings. Three types of samples were collected on each site: 10-composite samples, 20-composite samples, and individual or post hole samples; 10-composite sampling is the method of choice because it yields a given level of accuracy and precision for the least cost. Gamma measurements can be used to reduce surface soil sampling on some sites. 2 refs., 5 figs., 7 tabs

  12. DNA damage in isolated rat hepatocytes exposed to C.I. pigment orange 5 and C.I. pigment yellow 12 by the alkaline comet assay

    DEFF Research Database (Denmark)

    Møller, P; Wallin, Håkan; Grunnet, N

    1998-01-01

    , and C.I. pigment orange 5 is a naphthol-azo pigment. The pigments are virtually insoluble in aqueous solutions, and they have not been tested extensively for toxicological effects. C.I. pigment orange 5 increased the levels of DNA damage at 5 microg/ml (P pigment yellow 12 at 20 microg....../ml (P effect of incubation time (20, 40, and 80 min) of the same concentrations of the pigments was tested. The levels of DNA damage were increased up to 80 min. Both pigments produced DNA damage that was in the same range as the food carcinogen 2-amino-3,8-dimethylimidazo[4,5-f......The induction of DNA damage by commonly used printing ink pigments, C.I. pigment orange 5 (C.I. 12075) and C.I. pigment yellow 12 (C.I. 21090), was investigated in freshly isolated rat hepatocytes with the comet assay. C.I. pigment yellow 12 is a 3,3'-dichlorobenzidine-based diarylide pigment...

  13. The influence of meteorological factors and biomass burning on surface ozone concentrations at Tanah Rata, Malaysia

    Science.gov (United States)

    Toh, Ying Ying; Lim, Sze Fook; von Glasow, Roland

    2013-05-01

    The surface ozone concentrations at the Tanah Rata regional Global Atmosphere Watch (GAW) station, Malaysia (4°28‧N, 101°23‧E, 1545 m above Mean Sea Level (MSL)) from June 2006 to August 2008 were analyzed in this study. Overall the ozone mixing ratios are very low; the seasonal variations show the highest mixing ratios during the Southwest monsoon (average 19.1 ppb) and lowest mixing ratios during the spring intermonsoon (average 14.2 ppb). The diurnal variation of ozone is characterised by an afternoon maximum and night time minimum. The meteorological conditions that favour the formation of high ozone levels at this site are low relative humidity, high temperature and minimum rainfall. The average ozone concentration is lower during precipitation days compared to non-precipitation days. The hourly averaged ozone concentrations show significant correlations with temperature and relative humidity during the Northeast monsoon and spring intermonsoon. The highest concentrations are observed when the wind is blowing from the west. We found an anticorrelation between the atmospheric pressure tide and ozone concentrations. The ozone mixing ratios do not exceed the recommended Malaysia Air Quality Guidelines for 1-h and 8-h averages. Five day backward trajectories on two high ozone episodes in 07 August 2006 (40.0 ppb) and 24 February 2008 (45.7 ppb) are computed using the HYbrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model to investigate the origin of the pollutants and influence of regional transport. The high ozone episode during 07 August 2006 (burning season during southwest monsoon) is mainly attributed to regional transport from biomass burning in Sumatra, whereas favourable meteorological conditions (i.e. low relative humidity, high temperature and solar radiation, zero rainfall) and long range transport from Indo-China have elevated the ozone concentrations during 24 February 2008.

  14. Temperature and concentration stratification effects on non-Newtonian fluid flow past a cylindrical surface

    Science.gov (United States)

    Rehman, Khalil Ur; Khan, Abid Ali; Malik, M. Y.; Zehra, Iffat; Ali, Usman

    The theme of present work is to report the numerical solution of mixed convection tangent hyperbolic fluid flow towards stretching cylindrical surface immersed in a double stratified media. The fluid flow is attained through no slip condition. The flow regime characteristics are modelled in terms of partial differential equations. A similarity transformation is used to transform partial differential equations into coupled non-linear ordinary differential equations. A computational algorithm is executed to predict numerical results. The effects of flow controlling parameters namely, mixed convection parameter, thermal stratification and solutal stratification parameters on velocity, temperature and concentration are examined and offered by means of graphical outcomes. It is noticed that in the presence of mixed convection effect both the fluid temperature and concentration are decreasing function of thermal stratification and solutal stratification parameters respectively. The obtained values are certified by developing comparison with existing values and an excellent agreement is observed which confirms the execution of computational algorithm.

  15. Estimating sub-surface dispersed oil concentration using acoustic backscatter response.

    Science.gov (United States)

    Fuller, Christopher B; Bonner, James S; Islam, Mohammad S; Page, Cheryl; Ojo, Temitope; Kirkey, William

    2013-05-15

    The recent Deepwater Horizon disaster resulted in a dispersed oil plume at an approximate depth of 1000 m. Several methods were used to characterize this plume with respect to concentration and spatial extent including surface supported sampling and autonomous underwater vehicles with in situ instrument payloads. Additionally, echo sounders were used to track the plume location, demonstrating the potential for remote detection using acoustic backscatter (ABS). This study evaluated use of an Acoustic Doppler Current Profiler (ADCP) to quantitatively detect oil-droplet suspensions from the ABS response in a controlled laboratory setting. Results from this study showed log-linear ABS responses to oil-droplet volume concentration. However, the inability to reproduce ABS response factors suggests the difficultly in developing meaningful calibration factors for quantitative field analysis. Evaluation of theoretical ABS intensity derived from the particle size distribution provided insight regarding method sensitivity in the presence of interfering ambient particles. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Measurement of the radon exhalation rate from the medium surface by tracing the radon concentration

    International Nuclear Information System (INIS)

    Yanliang Tan; Detao Xiao

    2013-01-01

    The paper will present a method based on the accumulation chamber technique for measuring of radon exhalation from the medium surface. A radon monitor traces the change of radon concentration in the accumulation chamber, and then the radon exhalation can be obtained accurately through linear fit. Based on our recent experiments, the radon exhalation rate from the medium surface obtained from this method is in good agreement with the actual exhalation rate of our simulation facility. This method is superior to the competition method which obtains the radon exhalation through the exponential fit by an external PC-system. The calculation for the exponential fit is very easy by computer and related software. However, for portable instruments, the single chip microcomputer can't calculate the exponential fit rapidly. Thus, this method is usable for developing the new portable instrument to classify building materials, etc. (author)

  17. Reducing surface water total and methyl mercury concentrations and bioavailability using a coagulation-wetland system

    Science.gov (United States)

    Kraus, T. E.; Fleck, J.; Henneberry, Y. K.; Stumpner, E. B.; Krabbenhoft, D. P.; Bachand, P.; Randall, P.

    2013-12-01

    With the recent passage of laws regulating concentrations and loads of mercury (Hg) in surface waters, there is a need to develop management practices that will reduce the export of Hg from both point and non-point sources. Coagulation with metal based salts to remove particles and dissolved organic matter (DOM) from solution is a practice commonly employed by drinking water utilities. Because dissolved Hg is associated with particles and DOM, it follows that Hg should also be removed during the coagulation process and end up associated with the organo-metal precipitate, termed flocculate (floc). The effectiveness of iron- and aluminum-based coagulants for removing both inorganic and methyl mercury (IHg and MeHg, respectively) from solution was demonstrated in laboratory studies conducted on agricultural drainage waters of the Sacramento-San Joaquin Delta: dissolved concentrations of MeHg decreased by 80% while IHg decreased by 97% following coagulation. To test the field application of this technology, samples were collected from the inflows and outflows of wetland treatment cells constructed in the central Delta of California. This replicated field experiment includes three replicates each of three inflow waters treatments: (1) iron sulfate addition, (2) polyaluminum chloride addition, and (3) untreated controls. Water entering and exiting the nine treatment cells was sampled approximately monthly over a 1-year period for total Hg and MeHg in both the dissolved and particulate aqueous phases. Initial results confirm that coagulant addition is removing Hg (total and methyl, particulate and dissolved) from solution and sequestering it in the floc. Seasonal effects on DOM concentration and other factors appear to effect whether passage through the wetland cells alters surface water dissolved organic carbon (DOC) and Hg concentrations. Related studies will examine whether the presence of the floc affects the production and fate of MeHg within the wetland cells. If

  18. Optimization and design of pigments for heat-insulating coatings

    International Nuclear Information System (INIS)

    Wang Guang-Hai; Zhang Yue

    2010-01-01

    This paper reports that heat insulating property of infrared reflective coatings is obtained through the use of pigments which diffuse near-infrared thermal radiation. Suitable structure and size distribution of pigments would attain maximum diffuse infrared radiation and reduce the pigment volume concentration required. The optimum structure and size range of pigments for reflective infrared coatings are studied by using Kubelka—Munk theory, Mie model and independent scattering approximation. Taking titania particle as the pigment embedded in an inorganic coating, the computational results show that core-shell particles present excellent scattering ability, more so than solid and hollow spherical particles. The optimum radius range of core-shell particles is around 0.3 ∼ 1.6 μm. Furthermore, the influence of shell thickness on optical parameters of the coating is also obvious and the optimal thickness of shell is 100–300 nm. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  19. Response of the equatorial Pacific to chlorophyll pigment in a mixed layer isopycnal ocean general circulation model

    Digital Repository Service at National Institute of Oceanography (India)

    Nakamoto, S.; PrasannaKumar, S.; Oberhuber, J.M.; Ishizaka, J.; Muneyama, K.; Frouin, R.

    pigment concentration from the Coastal Zone Color Scanner (CZCS). In the equatorial Pacific heat accumulation due to a higher abundance of chlorophyll pigments in the equatorial Pacific leads to a decrease of the mixed layer thickness. This generates...

  20. Accumulation of pigment granules in lacrymal gland epithelium in practolol-treated beagle dogs.

    Science.gov (United States)

    Tsuchitani, M; Narama, I; Kohda, S

    1989-04-01

    A 6-month oral toxicity test of practolol was carried out in beagle dogs as a reference control for a newly developed beta blocker. No significant drug-induced changes were detected in any animals by various ophthalmological examinations such as ERG, tear flow, lysozymal activity in tears, etc. However, an unusual pathological change was detected in the lacrymal gland of all five dogs treated with practolol and not in control animals. Macroscopically, the lacrymal glands assumed a blackish brown to deep black colour on both the outside and the cut surface. Microscopically, fine, dark-brown pigment granules were present in the apical and supra-nuclear portion of the cytoplasm of predominantly serosal type epithelial cells. These pigments reacted positively to Schmorl's method for lipofuscin, but gave a negative PAS reaction for polysaccharide, Prussian blue for iron and Ziehl-Neelsen method for ceroid pigment. They were detected as membrane-bound electron-dense bodies by electron microscopy. Similar pigments were also deposited in the cytoplasm of the apocrine sweat gland. Although the mechanism of the accumulation of these granules is far from clear, concentration of practolol in the lacrymal gland is considered to be very closely related to the presence of these granules. A possible mechanism for ocular toxicity by practolol, involving this change, is discussed.

  1. Pigmentos maculares Macular pigments

    Directory of Open Access Journals (Sweden)

    Renata Canovas

    2009-12-01

    Full Text Available A luteína e a zeaxantina são pigmentos amarelos que se localizam na mácula. Devido à sua localização, diminuem e filtram a quantidade de luz principalmente azul que chega aos fotorreceptores, atuam como antioxidantes e podem melhorar a qualidade visual. Esta é uma revisão do seu mecanismo de incorporação, ação, possíveis aplicações e conhecimento científico a respeito.Lutein and Zeaxanthin are yellow pigments located at the macula. Because of your location macular pigments decrease and filter the amount of blue light that reach photoreceptors, protect the outer retina from oxidative stress and may improve the vision quality. This is a review regarding incorporation mechanism, function and knowledge update.

  2. Spatial pattern of hormone and antibiotic concentrations in surface waters in Delaware

    Science.gov (United States)

    Vaicunas, R.; Inamdar, S. P.; Dutta, S.; Aga, D.; Zimmerman, L. R.

    2011-12-01

    Water quality surveys of the U.S. have confirmed the presence of hormones and antibiotics in some surface waters. Although the reported concentrations of these substances are extremely low, there is substantial concern about their effect on aquatic species. For example, chronic exposure to estradiol (E2β) concentrations as low as 40 ng/L have been shown to cause endocrine disruption in fish. Furthermore, there is potential for contaminants to enter our drinking supply. Significant sources of hormones and antibiotics include discharge from concentrated animal feeding operations (CAFOs) and wastewater treatment plants as well as runoff from agricultural land receiving application of animal manure. Since Sussex County, Delaware is one of the leading poultry producing counties in the nation, and many farmers in the state use poultry litter as fertilizer for their crops, it is critical to study the concentrations of contaminants in surface waters. Fifty surface water (streams, lakes, and ponds) sampling locations throughout the state of Delaware were chosen based on DNREC (Delaware Department of Natural Resources and Environmental Control) data. Locations with the highest nitrogen and phosphorus levels were assumed to be associated with agriculture and wastewater sources and therefore were likely to be contaminated with hormones and antibiotics. The first set of sampling occurred in April representing high-flow conditions, and the second set will occur in September representing low-flow conditions. Water samples will be screened through the cost-effective enzyme-linked immunosorbent assay (ELISA) method followed by more rigorous analyses of selected samples using liquid chromatography-mass spectrometry (LC/MS/MS). ELISA screening includes estradiol (E2β), sulfamethazine and triclosan, while LC/MS/MS will quantify both free and conjugated forms of estrone (E1), estradiol (E2β), estriol (E3), as well as selected sulfa and tetracycline antibiotics. Initial ELISA results

  3. A preformulation evaluation of a photosensitive surface active compound, explaining concentration dependent degradation.

    Science.gov (United States)

    Sigfridsson, Kalle; Carlsson, Karin E

    2017-11-15

    A candidate drug within the cardiovascular area was identified during early research and evaluated for further development. The aim was to understand and explain the degradation mechanisms for the present compound. The stability of the active pharmaceutical ingredient (API) in solution and solid state was studied during different conditions. The bulk compound was exposed to elevated temperatures, increased relative humidity and stressed light conditions. Degradation of the drug in solutions was followed in the presence versus absence of ethylenediaminetetraacetic acid (EDTA), during aerobic versus anaerobic conditions, stored protected from light versus exposed to light and as a function of pH and concentration. It was possible to improve the stability by adding EDTA and completely abolish degradation by storing dissolved compound at anaerobic conditions. Solutions of API were stable between pH3 and 7, with some degradation at pH1, when stored protected from light and at 22°C, but degrade rapidly when exposed to ambient light conditions. The degradation products were identified by mass spectroscopy. Degradation schemes were drawn. There was concentration dependence in the degradation of dissolved drug when exposed to light, showing a titration behavior that concurred with the measured critical micelle/aggregation concentration (CMC/CAC) of the compound. The compound was stable in solution during the investigated time period, at concentrations above CMC/CAC, where the molecule was protected from photodegradation when the compound aggregated. Below CMC/CAC, a significant degradation of the API occurred. This may be a potential explanation why other surface active compounds show concentration dependent degradation. The photosensitivity was also observed for the neutral compound in crystalline and amorphous form, as well as for the crystalline chloride salt of the drug. However, the degradation of amorphous form was faster compared to crystalline material. No

  4. The impact of anthropogenic and biogenic emissions on surface ozone concentrations in Istanbul.

    Science.gov (United States)

    Im, Ulas; Poupkou, Anastasia; Incecik, Selahattin; Markakis, Konstantinos; Kindap, Tayfun; Unal, Alper; Melas, Dimitros; Yenigun, Orhan; Topcu, Sema; Odman, M Talat; Tayanc, Mete; Guler, Meltem

    2011-03-01

    Surface ozone concentrations at Istanbul during a summer episode in June 2008 were simulated using a high resolution and urban scale modeling system coupling MM5 and CMAQ models with a recently developed anthropogenic emission inventory for the region. Two sets of base runs were performed in order to investigate for the first time the impact of biogenic emissions on ozone concentrations in the Greater Istanbul Area (GIA). The first simulation was performed using only the anthropogenic emissions whereas the second simulation was performed using both anthropogenic and biogenic emissions. Biogenic NMVOC emissions were comparable with anthropogenic NMVOC emissions in terms of magnitude. The inclusion of biogenic emissions significantly improved the performance of the model, particularly in reproducing the low night time values as well as the temporal variation of ozone concentrations. Terpene emissions contributed significantly to the destruction of the ozone during nighttime. Biogenic NMVOCs emissions enhanced ozone concentrations in the downwind regions of GIA up to 25ppb. The VOC/NO(x) ratio almost doubled due to the addition of biogenic NMVOCs. Anthropogenic NO(x) and NMVOCs were perturbed by ±30% in another set of simulations to quantify the sensitivity of ozone concentrations to the precursor emissions in the region. The sensitivity runs, as along with the model-calculated ozone-to-reactive nitrogen ratios, pointed NO(x)-sensitive chemistry, particularly in the downwind areas. On the other hand, urban parts of the city responded more to changes in NO(x) due to very high anthropogenic emissions. Copyright © 2010 Elsevier B.V. All rights reserved.

  5. Effects of trans-Eurasian transport of anthropogenic pollutants on surface ozone concentrations over China

    Science.gov (United States)

    Liu, J.; Li, X.; Mauzerall, D. L.; Emmons, L. K.; Horowitz, L. W.; Guo, Y.; Tao, S.

    2015-12-01

    Due to a lack of industrialization in Western China, surface air there was, until recently, believed to be relatively unpolluted. However, recent measurements and modeling studies have found high levels of ozone (O3) there. Based on the state-of-the-science global chemical transport model MOZART-4, we identify the origin, pathway, and mechanism of trans-Eurasian transport of air pollutants to Western China in 2000. MOZART-4 generally simulates well the observed surface O3 over inland areas of China. Simulations find surface ozone concentrations over Western China on average to be about 10 ppbv higher than Eastern China. Using sensitivity studies as well as a fully-tagged approach, we find that anthropogenic emissions from all Eurasian regions except China contribute 10-15 ppbv surface O3 over Western China, superimposed upon a 35-40 ppbv natural background. Transport from European anthropogenic sources to Northwestern China results in 2-6 ppbv O3 enhancements in spring and summer. Indian anthropogenic sources strongly influence O3 over the Tibetan Plateau during the summer monsoon. Transport of O3 originating from emissions in the Middle East occasionally reach Western China and increase surface ozone there by about 1-4 ppbv. These influences are of similar magnitude as trans-Pacific and transatlantic transport of O3 and its precursors, indicating the significance of trans-Eurasian ozone transport in hemispheric transport of air pollution. Our study further indicates that mitigation of anthropogenic emissions from Europe, the Indian subcontinent, and the Middle East could benefit public health and agricultural productivity in Western China.

  6. Internal pigment cells respond to external UV radiation in frogs.

    Science.gov (United States)

    Franco-Belussi, Lilian; Nilsson Sköld, Helen; de Oliveira, Classius

    2016-05-01

    Fish and amphibians have pigment cells that generate colorful skins important for signaling, camouflage, thermoregulation and protection against ultraviolet radiation (UVR). However, many animals also have pigment cells inside their bodies, on their internal organs and membranes. In contrast to external pigmentation, internal pigmentation is remarkably little studied and its function is not well known. Here, we tested genotoxic effects of UVR and its effects on internal pigmentation in a neotropical frog, Physalaemus nattereri We found increases in body darkness and internal melanin pigmentation in testes and heart surfaces and in the mesenterium and lumbar region after just a few hours of UVR exposure. The melanin dispersion in melanomacrophages in the liver and melanocytes in testes increased after UV exposure. In addition, the amount of melanin inside melanomacrophages cells also increased. Although mast cells were quickly activated by UVR, only longer UVR exposure resulted in genotoxic effects inside frogs, by increasing the frequency of micronuclei in red blood cells. This is the first study to describe systemic responses of external UVR on internal melanin pigmentation, melanomacrophages and melanocytes in frogs and thus provides a functional explanation to the presence of internal pigmentation. © 2016. Published by The Company of Biologists Ltd.

  7. Characterization of pre-hispanic pigments by modern analytical techniques; Caracterizacion de pigmentos prehispanicos por tecnicas analiticas modernas

    Energy Technology Data Exchange (ETDEWEB)

    Ortega A, M

    2003-07-01

    In this work, the study of mural painting pigments from two archaeological sites (The Great Temple in Mexico city and Cacaxtla) was performed to know their materials composition, identify their structural characteristics and properties by using modern analytical techniques. Blue, ochre, red and black pigments of Mexica culture (1325-1521 a.C. / late Post Classic period); blue, ochre, red, brown, pink, green and white of Olmeca- Xicalanca culture (700-900 a.C. / Epiclassic period) were studied. Data about materials used, technological evolution, mineralogical background, cultural interchange and origin was obtained. Environmental exposition of these paintings since their discovering has produced changes and damage on their materials. Therefore, stability of some pigments has been notorious, ''Maya Blue'' specially presents extraordinary resistance to diluted and concentrated acids and alkalis including boiling condition, acqua regia, solvents, oxidant and reducing agents, moderate heat and biocorrosi6n; for that reason its study was emphasized. ''Maya Blue'' pigment was synthesized in laboratory using the processes described by historic sources (with indigophera suffruticosa leaves and synthetic indigo) up to obtain a stable pigment including acqua regia action. Clay matrix sorbs nearly 0.4 weight percent of organic dye, which cover 79% of palygorskita surface area. (Author)

  8. SYNTHESIS AND CHARACTERIZATION OF BLACK, RED AND YELLOW PIGMENT MADE FROM IRON SANDS

    Directory of Open Access Journals (Sweden)

    Bilalodin

    2015-11-01

    Full Text Available Synthesis and characteristics of the black, red and yellow pigment made from iron sand have been done. The purpose of this research is performing the synthesis and characterization of pigments using raw materials of iron sands using calcination methods. The manufacture of black pigment was done by mixing iron sand with a solution of NaOH and NH4OH then heating them at a temperature of 800 °C. The red pigment was made by dissolving iron sand in a solution of H2SO4 and it was heated at a temperature of 650 °C. While the yellow pigment was made of red pigment powder dissolved into a solution of HCl and heated at a temperature of 250 °C. Pigment powders were characterized by using XRD, SEM-EDX and PSA and Crommameter. The results showed that the black, red and yellow powder pigment have a cubic crystal structure with the form of the surface morphology and grain size as follows: the particles of the black pigment is uniform spherical granules with a grain size of 926.4 nm, the red pigment granules have a spherical shape with grain size of 72.2 nm and yellow pigments have a spherical shape with grain size of 349 nm. The main elements of black, red and yellow pigment are iron (Fe and oxygen (O. From the result of pigment powder test using Crommameter it was found that L * a * b * and DE coordinat of black pigment were 23.76, 1.35, 1.43, 2.339, red pigment are 43.23, 16 , 17.3 and 9.893, and yellow pigment are 66.76, 14.84, 49.95 and 4.862. The pigment colors produced are in accordance with standards.

  9. Bayesian Estimation of the Active Concentration and Affinity Constants Using Surface Plasmon Resonance Technology.

    Directory of Open Access Journals (Sweden)

    Feng Feng

    Full Text Available Surface plasmon resonance (SPR has previously been employed to measure the active concentration of analyte in addition to the kinetic rate constants in molecular binding reactions. Those approaches, however, have a few restrictions. In this work, a Bayesian approach is developed to determine both active concentration and affinity constants using SPR technology. With the appropriate prior probabilities on the parameters and a derived likelihood function, a Markov Chain Monte Carlo (MCMC algorithm is applied to compute the posterior probability densities of both the active concentration and kinetic rate constants based on the collected SPR data. Compared with previous approaches, ours exploits information from the duration of the process in its entirety, including both association and dissociation phases, under partial mass transport conditions; do not depend on calibration data; multiple injections of analyte at varying flow rates are not necessary. Finally the method is validated by analyzing both simulated and experimental datasets. A software package implementing our approach is developed with a user-friendly interface and made freely available.

  10. Simultaneous measurement of gas concentration and temperature by the ball surface acoustic wave sensor

    Science.gov (United States)

    Yamanaka, Kazushi; Akao, Shingo; Takeda, Nobuo; Tsuji, Toshihiro; Oizumi, Toru; Tsukahara, Yusuke

    2017-07-01

    We have developed a ball surface acoustic wave (SAW) trace moisture sensor with an amorphous silica sensitive film and realized wide-range measurement from 0.017 ppmv [a frost point (FP) of -99 °C] to 6.0 × 103 ppmv (0 °C FP). However, since the sensitivity of the sensor depends on the temperature, measurement results are disturbed when the temperature largely changes. To overcome this problem, we developed a method to simultaneously measure temperature and gas concentration using a ball SAW sensor. Temperature and concentration is derived by solving equations for the delay time change at two frequencies. When the temperature had a large jump, the delay time change was significantly disturbed, but the water concentration was almost correctly measured, by compensating the sensitivity change using measured temperature. The temperature measured by a ball SAW sensor will also be used to control the ball temperature. This method will make a ball SAW sensor reliable in environments of varying temperatures.

  11. Can We Trust Real Time Measurements of Lung Deposited Surface Area Concentrations in Dust from Powder Nanomaterials?

    DEFF Research Database (Denmark)

    Levin, Marcus; Witschger, Olivier; Bau, Sebastien

    2016-01-01

    A comparison between various methods for real-time measurements of lung deposited surface area (LDSA) using spherical particles and powder dust with specific surface area ranging from 0.03 to 112 m2 g-1 was conducted. LDSA concentrations measured directly using Nanoparticle Surface Area Monitor...... (NSAM) and Aerotrak and were compared to LDSA concentrations recalculated from size distribution measurements using Electrical Low Pressure Impactor (ELPI) and Fast Mobility Particle Sizer (FMPS). FMPS and ELPI measurements were also compared to dust surface area concentrations estimated from...... gravimetrical filter measurements and specific surface areas. Measurement of LDSA showed very good correlation in measurements of spherical particles (R2 > 0.97, Ratio 1.0 to 1.04). High surface area nanomaterial powders showed a fairly reliable correlation between NSAM and Aerotrak (R2 0...

  12. Use of phytoplankton pigments in estimating food selection of three marine copepods

    DEFF Research Database (Denmark)

    Oechsler-Christensen, B.; Jonasdottir, Sigrun; Henriksen, P.

    2012-01-01

    Experiments were carried out to test the use of algal pigments in zooplankton grazing studies with a special emphasis on estimation of food selection. The results demonstrated that pigment composition of the phytoplankton food was reflected closely in the three copepod species Centropages typicus......, Temora longicornis and Acartia tonsa, as well as in their faecal pellets. The fate of the phytoplankton pigments was studied in A. tonsa fed a diatom and a cryptophyte at a low and a high prey concentration. The concentration of gut pigments generally declined rapidly within the first 5–10 min after...... feeding terminated. The decline in pigment concentration was faster in copepods fed high concentrations of phytoplankton and specially when fed the diatom. However, after 3h of no feeding only minor changes in gut pigment composition were found mainly in alloxanthin, chlorophyll a and diadinoxanthin...

  13. The bioefficacy of microemulsified natural pigments in egg yolk pigmentation.

    Science.gov (United States)

    Chow, P Y; Gue, S Z; Leow, S K; Goh, L B

    2014-01-01

    1. This study was designed to test the hypothesis that microemulsified carotenoid products show improved bioavailability over corresponding regular preparations, leading to greater yolk pigmentation at lower dosages. 2. The first trial was conducted using a maize-soya bean basal diet supplemented with either 0.25, 0.5, 0.75, 1.0 and 1.25 g/kg of microemulsified Red or non-microemulsified Red. The second trial involved feeding microemulsified Yellow or non-microemulsified Yellow using a similar dosage range. The layers were divided into 4 replicates of 8 layers each (32 layers per treatment). The 8 cages of layers were fed from a single feed trough. Feed and water were provided ad libitum throughout the trial. Each week, the eggs were collected. The whole liquid egg colour was determined by means of a commercially available yolk colour fan. Where required, HPLC-(high-performance liquid chromatography) based analysis of trans-capsanthin or trans-lutein equivalents using the Association of Analytical Communities method was carried out. Data were statistically analysed by one-way ANOVA method using Statgraphics. 3. Results showed that the colour and carotenoid content of the egg yolk increased with increasing amount of carotenoids in the diet. The colour of egg yolks from layers fed similar concentrations of microemulsified versus the regular preparation was significantly different. At the commercial recommended dose of one g/kg regular Yellow or Red product, the microemulsified pigmenter is able to provide the equivalent yolk colour at a 20-30% lower dose. 4. In conclusion, the trial results supported the hypothesis that a desired yolk colour score is achievable at a significantly lower inclusion rate when carotenoid molecules are emulsified using the microemulsion nanotechnology.

  14. Spatial Evaluation of Heavy Metals Concentrations in the Surface Sediment of Taihu Lake

    Science.gov (United States)

    Niu, Yong; Jiao, Wei; Yu, Hui; Niu, Yuan; Pang, Yong; Xu, Xiangyang; Guo, Xiaochun

    2015-01-01

    With regard to the size of China’s freshwater lakes, Taihu Lake ranks third and it plays an important role in the supply of drinking water, flood prevention, farming and navigation, as well as in the travelling industry. The problem of environmental pollution has attracted widespread attention in recent years. In order to understand the levels, distribution and sources of heavy metals in sediments of Taihu Lake, random selection was carried out to obtain 59 samples of surface sediment from the entire lake and study the concentrations of Pb, Cd, Cu, Zn, Cr and Ni. Toxic units were also calculated to normalize the toxicities caused by various heavy metals. As a result, Cd and Cu in sediment were considered lower than the effect range low (ERL) at all regions where samples were gathered, while Pb and Ni were categorized into ERL-effect range median (ERM) at over 22% of the regions where samples were obtained. Nevertheless, all average concentrations of the samples were below the level of potential effect. According to the findings of this research, significant spatial heterogeneity existed in the above heavy metals. In conclusion, the distribution areas of heavy metals with higher concentrations were mainly the north bays, namely Zhushan Bay, Meiliang Bay as well as Gonghu Bay. The distribution areas of Cu, Zn, Cr and Ni with higher concentration also included the lake’s central region, whereas the uniform distribution areas of those with lower concentrations were the lake’s southeast region. In addition, it was most probable that the spatial distribution of heavy metals was determined by river inputs, whereas atmospheric precipitation caused by urban and traffic contamination also exerted considerable effects on the higher concentrations of Pb and Cd. Through evaluating the total amount of toxic units (ΣTU), it was found that higher toxicity existed primarily in the north bays and central region of the lake. If the heavy metals were sorted by the reduction of

  15. Self-Normalized Photoacoustic Technique for the Quantitative Analysis of Paper Pigments

    Science.gov (United States)

    Balderas-López, J. A.; Gómez y Gómez, Y. M.; Bautista-Ramírez, M. E.; Pescador-Rojas, J. A.; Martínez-Pérez, L.; Lomelí-Mejía, P. A.

    2018-03-01

    A self-normalized photoacoustic technique was applied for quantitative analysis of pigments embedded in solids. Paper samples (filter paper, Whatman No. 1), attached with the pigment: Direct Fast Turquoise Blue GL, were used for this study. This pigment is a blue dye commonly used in industry to dye paper and other fabrics. The optical absorption coefficient, at a wavelength of 660 nm, was measured for this pigment at various concentrations in the paper substrate. It was shown that Beer-Lambert model for light absorption applies well for pigments in solid substrates and optical absorption coefficients as large as 220 cm^{-1} can be measured with this photoacoustic technique.

  16. Analysis of concentric and eccentric contractions in biceps brachii muscles using surface electromyography signals and multifractal analysis.

    Science.gov (United States)

    Marri, Kiran; Swaminathan, Ramakrishnan

    2016-06-23

    Muscle contractions can be categorized into isometric, isotonic (concentric and eccentric) and isokinetic contractions. The eccentric contractions are very effective for promoting muscle hypertrophy and produce larger forces when compared to the concentric or isometric contractions. Surface electromyography signals are widely used for analyzing muscle activities. These signals are nonstationary, nonlinear and exhibit self-similar multifractal behavior. The research on surface electromyography signals using multifractal analysis is not well established for concentric and eccentric contractions. In this study, an attempt has been made to analyze the concentric and eccentric contractions associated with biceps brachii muscles using surface electromyography signals and multifractal detrended moving average algorithm. Surface electromyography signals were recorded from 20 healthy individuals while performing a single curl exercise. The preprocessed signals were divided into concentric and eccentric cycles and in turn divided into phases based on range of motion: lower (0°-90°) and upper (>90°). The segments of surface electromyography signal were subjected to multifractal detrended moving average algorithm, and multifractal features such as strength of multifractality, peak exponent value, maximum exponent and exponent index were extracted in addition to conventional linear features such as root mean square and median frequency. The results show that surface electromyography signals exhibit multifractal behavior in both concentric and eccentric cycles. The mean strength of multifractality increased by 15% in eccentric contraction compared to concentric contraction. The lowest and highest exponent index values are observed in the upper concentric and lower eccentric contractions, respectively. The multifractal features are observed to be helpful in differentiating surface electromyography signals along the range of motion as compared to root mean square and median

  17. Evaluation of Relation between Mercury Concentration in Saliva with Number and Surfaces of Amalgam Fillings

    Directory of Open Access Journals (Sweden)

    F. Agha Hosseini

    2004-09-01

    Full Text Available Statement of Problem: Amalgam is the most widely used dental restorative material.However, because of continuous low-level release of Mercury from amalgam fillings, its safety has been questionable.Purpose: The aim of this study was the evaluation of concentration of Mercury in saliva before and after amalgam fillings and its relation with numbers and surfaces of amalgam fillings.Materials and Methods: In an analytic interventional study we surveyed concentration Mercury in saliva before and after amalgam fillings. Twenty-five Patients (9 male, 16 female who referred to oral medicine department of Tehran university of medical scienceand Haj- Abdol- Vahab medical center who had no amalgam fillings were selected and the samples of saliva (5cc was collected before fillings. After that all of posterior decayed teeth were filled in an appointment with amalgam and, 24 hours later, the second samplesof saliva (5cc was collected. The amount of saliva Mercury before and after filling was measured and its difference was analyzed by paired t- test.Results: In this study the mean of Mercury in saliva was 0.00896 μg/ml before and 0.16404 μg/ml after amalgam fillings. The mean of number of fillings was 1.96 and mean of size of surfaces was 76.43 mm2 and mean of consumption amalgam was 4.1 units.Conclusion: There was no significant correlation between age (P=0.677, sex, number of fillings (P=0.055, number of surface of filling (P=0.059 and size of surfaces of fillings (P=0.072, with Mercury levels in saliva after amalgam fillings. There was a significant relation between Mercury level of saliva after fillings and amalgam amount (P= 0.036.Therefore amalgam may be designate a significant source for Mercury release in saliva.Since this is a preliminary study, it needs supplementary evaluations in saliva, blood and urine in different periods after amalgam fillings.

  18. Combustion synthesis of cobalt pigments: Blue and pink

    OpenAIRE

    Mimani, T; Ghosh, Samrat

    2000-01-01

    Idiochromatic blue cobalt aluminate (CoAl2O4) and purple pyroborate Co2B2O5 were prepared by solution combustion method using corresponding metal nitrates, boric acid and carbohydrazide mixtures. Allochromatic Co2+ doped in Al2O3/ZnAl2O4 and Mg2B2O5 pigments having the same colour intensity as idiochromatic pigments were obtained similarly. All the pigments are voluminous, homogeneously coloured with a large surface area. The products are characterized by their characteristic colours, XRD, IR...

  19. Heavy metal concentrations in the surface marine sediments of Sfax Coast, Tunisia.

    Science.gov (United States)

    Gargouri, Dorra; Azri, Chafai; Serbaji, Mohamed Moncef; Jedoui, Younes; Montacer, Mabrouk

    2011-04-01

    Sixty-seven surface marine sediment samples in the Sfax (Tunisia) were analyzed by inductively coupled plasma-atomic emission spectrometry for seven heavy metals (Pb, Ni, Cu, Cr, Zn, Cd, and Fe). Metal concentrations were compared with natural values, marine sediment quality standards, and also with other results concerning sediments from several Mediterranean coasts. The study of their spatial distributions refined by complementary approaches including principal component analysis, enrichment factors, and geoaccumulation index showed a significant impact of multiple anthropogenic sources. These included industrial sources and municipal discharges of the urban Sfax and also non-controlled discharges in rural zones close to the coastline. Moderate pollution of sediments, especially by Pb, Zn, and Ni, was shown to exist in localized sites. Besides, it was shown that other sites, slightly to highly enriched in terms of Cu, Cr, and Cd, are characterized by a quality of sediments varying from unpolluted to moderately polluted.

  20. First observations of surface ozone concentration from the summit region of Mount Everest

    Science.gov (United States)

    Semple, John L.; Moore, G. W. K.

    2008-10-01

    The extreme height of Mount Everest is such that its summit region may periodically be in the lower stratosphere. In this regard it provides a unique location for observing the exchange of ozone between the upper troposphere and lower stratosphere. Here we report the first surface ozone measurements from the summit region of Mount Everest. Simultaneous measurements were recorded at different elevations on the north side from base camp (5676 m) to the summit (8848 m) during May 2005. The concentrations measured were as high as 70 ppb. Meteorological diagnostics suggest that the stratosphere as well as the long range transport of polluted tropospheric air masses from South East Asia are sources of the observed ozone. There is evidence that the source region for ozone in the vicinity of Mount Everest may vary with the onset of the summer monsoon.

  1. Heavy metal concentration in mangrove surface sediments from the north-west coast of South America.

    Science.gov (United States)

    Fernández-Cadena, J C; Andrade, S; Silva-Coello, C L; De la Iglesia, R

    2014-05-15

    Mangrove ecosystems are coastal estuarine systems confined to the tropical and subtropical regions. The Estero Salado mangrove located in Guayaquil, Ecuador, has suffered constant disturbances during the past 20 years, due to industrial wastewater release. However, there are no published data for heavy metals present in its sediments and the relationship with anthropogenic disturbance. In the present study, metal concentrations were evaluated in surface sediment samples of the mangrove, showing that B, Cd, Cu, Pb, Se, V, and Zn levels exceeded those declared in international environmental quality standards. Moreover, several metals (Pb, Sn, Cd, Ag, Mo, Zn and Ni) could be linked to the industrial wastewater present in the studied area. In addition, heavy metal levels detected in this mangrove are higher than previous reports on mangrove sediments worldwide, indicating that this mangrove ecosystem is one of the most disrupted on earth. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Shape of shock wave produced by a concentrated impact on a surface

    International Nuclear Information System (INIS)

    Nutt, G.; Klein, L.

    1981-01-01

    An approximate similarity solution, derived by Raizer, of a concentrated impact (or intense explosion) at the boundary of a semi-infinite volume of a perfect gas is used to determine the propagation velocity of the shock front as a function of its position. This velocity function is then used to obtain the shape of the propagating shock wave. It is shown that dish-shaped shock fronts are formed when the movement of the gas at the surface is into the gas region and that cup-shaped shock fronts are formed when the movement is out of the gas region. Comparison of these results with the shapes of explosions and meteorite craters are discussed

  3. NOAA JPSS Visible Infrared Imaging Radiometer Suite (VIIRS) Ice Concentration and Ice Surface Temperature Environmental Data Records (EDRs) from NDE

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a high quality operational Environmental Data Record (EDR) of Sea Ice Concentration (SIC) and Ice Surface Temperature (IST) from the Visible...

  4. Effect of interfacial state between pigment and binder on the UV curing proficiency

    International Nuclear Information System (INIS)

    Wang Dehai; Chen Xiaofang

    2004-01-01

    Effects of pigment modification to change pigment/binder interfacial characteristics and UV curing behavior were studied. The results show that the air absorbed on surface of the pigment plays an important role in hindering UV curing. In addition, there obviously exists the interface coupling effect between the pigment and the binder via the modifier of the pigment (reagent TEA). ESEM studies revealed that wetting property of the pigment was improved and binding between the pigment and the resin was strengthened after the pigment modification. EDS data showed an obvious enrichment of O-containing group of modification agent (-OH) in the interface and a shift of binding energy of the modifier was also detected. This may also contribute to the increase of curing proficiency due to the priority of the absorption of UV energy by the modifier TEA to that of pigment. The work demonstrated that the pigment modification could be used as a method to improve the UV curing efficiency. In the case of TEA, the curing rate of blue pigmented UV curable coating (125 μm) could be improved greatly (from 45s to 14s). The study have shown a promising application of various kinds of fillers as well as pigment in UV coatings. (authors)

  5. Sensitizing pigment in the fly

    International Nuclear Information System (INIS)

    Vogt, K.; Kirschfeld, K.

    1983-01-01

    The sensitizing pigment hypothesis for the high UV sensitivity in fly photoreceptors (R1-6) is further substantiated by measurements of the polarisation sensitivity in the UV. The quantum yield of the energy transfer from sensitizing pigment to rhodopsin was estimated by electrophysiological measurements of the UV sensitivity and the rhabdomeric absorptance (at 490 nm) in individual receptor cells. The transfer efficiency is >=0.75 in receptors with an absorptance in the rhabdomeres of 0.55-0.95. This result suggests that the sensitizing pigment is bound in some way to the rhodopsin. A ratio of two molecules of sensitizing pigment per one rhodopsin is proposed. (orig.)

  6. The Complete Solution of Fick's Second Law of Diffusion with Time-dependent Diffusion Coefficient and Surface Concentration

    DEFF Research Database (Denmark)

    Mejlbro, Leif

    1996-01-01

    Fick's Second Law of Diffusion with time-dependent diffusioncoefficient and surface concentration is solved. Mimicking the classicalsolution, special time-dependent surface concentration functions areconsidered. These models are used in giving estimates of the lifetimeof the structure, when the c...... the concrete cover is given, as well as estimatesof the thickness of the concrete cover, when the expected lifetime is given.*Note: Book tilte: Durability of Concrete in Saline Environment...

  7. The concentration of 137Cs in the surface of the Greek marine environment

    International Nuclear Information System (INIS)

    The radiological status of the Greek marine environment, prior to the Chernobyl accident, was characterized mainly by the fallout from nuclear weapon tests. However, the release of radioactivity into the environment from the accident in the Chernobyl Nuclear Power Plant and its deposition in the Greek marine environment resulted in an increase of the 137 Cs activity concentration by approximately one order of magnitude. In addition, the direct transport of radiocaesium into the North Aegean Sea has been further influenced by the late impact of the Chernobyl accident on the Greek marine environment, related to the transfer of 137 Cs, mainly through the Dnieper but also the Danube rivers, to the Black Sea and further to the North Aegean Sea through the Straits of Dardanelles. The aim of this work is to provide a present day picture of the geographic variation of the concentration of 137 Cs in the surface layer of the Greek marine environment and hence, to evaluate the annual committed effective dose delivered to humans through the ingestion pathway from marine sources.

  8. Concentration, enrichment and distribution of heavy metals in surface sediments of the Tangier Bay, Morocco

    Directory of Open Access Journals (Sweden)

    María Rocío Rodríguez-Barroso

    2010-11-01

    Full Text Available The distribution, enrichment, and accumulation of heavy metals in the surface sediments of the Tangier Bay, Morocco, were investigated. Surface sediment samples from eleven locations in the Bay of Tangier were collected in 2007 and characterized for grain size, organic matter and metal content (e.g. Fe, Mn, Cr, Cu, Ni, Pb, Zn and Cd. The evaluation of the heavy metal contamination status of the bay showed minor enrichment by the enrichment factors (EF calculation, corroborated by the metal pollution index (MPI. The results of a Pearson correlation showed high positive correlations among organic carbon and most metals (0.788 < r < 0.939 and cluster analysis grouped the stations inside the harbour (stations 1, 10 and 9 and in the vicinity of the principal rivers in the bay (stations 3 and 11, which showed the highest concentrations of metal content. The main sources of contamination are domestic and industrial effluents, which arise due to the lack of sewage treatment. However, these areas could not be classified as polluted when the data were compared with sediment quality guidelines (USEPA, 1997.

  9. Geostatistical integration and uncertainty in pollutant concentration surface under preferential sampling

    Directory of Open Access Journals (Sweden)

    Laura Grisotto

    2016-04-01

    Full Text Available In this paper the focus is on environmental statistics, with the aim of estimating the concentration surface and related uncertainty of an air pollutant. We used air quality data recorded by a network of monitoring stations within a Bayesian framework to overcome difficulties in accounting for prediction uncertainty and to integrate information provided by deterministic models based on emissions meteorology and chemico-physical characteristics of the atmosphere. Several authors have proposed such integration, but all the proposed approaches rely on representativeness and completeness of existing air pollution monitoring networks. We considered the situation in which the spatial process of interest and the sampling locations are not independent. This is known in the literature as the preferential sampling problem, which if ignored in the analysis, can bias geostatistical inferences. We developed a Bayesian geostatistical model to account for preferential sampling with the main interest in statistical integration and uncertainty. We used PM10 data arising from the air quality network of the Environmental Protection Agency of Lombardy Region (Italy and numerical outputs from the deterministic model. We specified an inhomogeneous Poisson process for the sampling locations intensities and a shared spatial random component model for the dependence between the spatial location of monitors and the pollution surface. We found greater predicted standard deviation differences in areas not properly covered by the air quality network. In conclusion, in this context inferences on prediction uncertainty may be misleading when geostatistical modelling does not take into account preferential sampling.

  10. Assessing metaldehyde concentrations in surface water catchments and implications for drinking water abstraction

    Science.gov (United States)

    Asfaw, Alemayehu; Shucksmith, James; Smith, Andrea; Cherry, Katherine

    2015-04-01

    Metaldehyde is an active ingredient in agricultural pesticides such as slug pellets, which are heavily applied to UK farmland during the autumn application season. There is current concern that existing drinking water treatment processes may be inadequate in reducing potentially high levels of metaldehyde in surface waters to below the UK drinking water quality regulation limit of 0.1 µg/l. In addition, current water quality monitoring methods can miss short term fluctuations in metaldehyde concentration caused by rainfall driven runoff, hampering prediction of the potential risk of exposure. Datasets describing levels, fate and transport of metaldehyde in river catchments are currently very scarce. This work presents results from an ongoing study to quantify the presence of metaldehyde in surface waters within a UK catchment used for drinking water abstraction. High resolution water quality data from auto-samplers installed in rivers are coupled with radar rainfall, catchment characteristics and land use data to i) understand which hydro-meteorological characteristics of the catchment trigger the peak migration of metaldehyde to surface waters; ii) assess the relationship between measured metaldehyde levels and catchment characteristics such as land use, topographic index, proximity to water bodies and runoff generation area; iii) describe the current risks to drinking water supply and discuss mitigation options based on modelling and real-time control of water abstraction. Identifying the correlation between catchment attributes and metaldehyde generation will help in the development of effective catchment management strategies, which can help to significantly reduce the amount of metaldehyde finding its way into river water. Furthermore, the effectiveness of current water quality monitoring strategy in accurately quantifying the generation of metaldehyde from the catchment and its ability to benefit the development of effective catchment management practices

  11. Determination of surface heterogeneity of D-mannitol by sessile drop contact angle and finite concentration inverse gas chromatography.

    Science.gov (United States)

    Ho, Raimundo; Hinder, Steven J; Watts, John F; Dilworth, Sarah E; Williams, Daryl R; Heng, Jerry Y Y

    2010-03-15

    The sensitivity of two techniques in tracking changes in surface energetics was investigated for a crystalline excipient, D-mannitol. Macroscopic crystals of D-mannitol were grown from saturated water solution by slow cooling, and sessile drop contact angle was employed to measure the anisotropic surface energy. The facet-specific surface energy was consistent with localised hydroxyl group concentrations determined by X-ray photoelectron spectroscopy (XPS), and was also in excellent agreement with the surface energy distribution of the powder form of mannitol measured via a new methodology using inverse gas chromatography (IGC) at finite concentrations. The gamma(SV)(d) was found to vary between 39.5 mJ/m(2) and 44.1 mJ/m(2) for contact angle and between 40 mJ/m(2) and 49 mJ/m(2) for IGC measurements. We report here, a high level of surface heterogeneity on the native mannitol crystal surfaces. When the surfaces of both D-mannitol samples (powder and large single crystals) were modified by dichlorodimethylsilane to induce surface hydrophobicity, both IGC and contact angle revealed a homogeneous surface due to functionalisation of mannitol crystal surface with methyl groups resulting in gamma(SV)(d) of approximately 34 mJ/m(2). It was shown that both IGC and contact angle techniques are able to detect surface chemical variations and detailed surface energetic distribution. 2010 Elsevier B.V. All rights reserved.

  12. Spectroscopic detection of a ubiquitous dissolved pigment degradation product in subsurface waters of the global ocean

    Directory of Open Access Journals (Sweden)

    R. Röttgers

    2012-07-01

    Full Text Available Measurements of light absorption by chromophoric dissolved organic matter (CDOM from subsurface waters of the tropical Atlantic and Pacific Oceans showed a distinct absorption shoulder at 410–415 nm. This indicates an underlying absorption of a pigment whose occurrence is partly correlated with the apparent oxygen utilization (AOU but also found in the deep chlorophyll maximum. A similar absorption maximum at ~415 nm was also found in the particulate fraction of samples taken below the surface mixing layer and is usually attributed to absorption by respiratory pigments of heterotrophic unicellular organisms. In our study, fluorescence measurements of pre-concentrated dissolved organic matter (DOM samples from 200–6000 m confirmed a previous study suggesting that the absorption at ~415 nm was related to fluorescence at 650 nm in the oxygen minimum zone. The absorption characteristics of this fluorophore was examined by fluorescence emission/excitation analysis and showed a clear excitation maximum at 415 nm that could be linked to the absorption shoulder in the CDOM spectra. The spectral characteristics of the substance found in the dissolved and particulate fraction did not match with those of chlorophyll a degradation products (as found in a sample from the sea surface but can be explained by the occurrence of porphyrin pigments from either heterotrophs or autotrophs. Combining the observations of the fluorescence and the 415-nm absorption shoulder suggests that there are high concentrations of a pigment degradation product in subsurface DOM of all major oceans. Most pronouncedly we found this signal in the deep chlorophyll maximum and the oxygen minimum zone of tropical regions. The origin, chemical nature, turnover rate, and fate of this molecule is so far unknown.

  13. Optimizing adsorption of blue pigment from wastewater by nano-porous modified Na-bentonite using spectrophotometry based on response surface method.

    Science.gov (United States)

    Moradi, Neshat; Salem, Shiva; Salem, Amin

    2018-03-15

    This work highlighted the effective activation of bentonite paste to produce nano-porous powder for removal of cationic dye from wastewater. The effects of activation parameters such as soda and moisture contents, ageing time and temperature were analyzed using response surface methodology (RSM). The significance of independent variables and their interactions were tested by blending the obtained powders with wastewater and then the adsorption was evaluated, spectrophotometrically. The experiments were carried out by preparation of pastes according to response surface methodology and central composite design, which is the standard method, was used to evaluate the effects and interactions of four factors on the treatment efficiency. RSM was demonstrated as an appropriate approach for optimization of alkali activation. The optimal conditions obtained from the desirable responses were 5.0wt% soda and 45.0wt% moisture, respectively in which the powder activation was carried out at 150°C. In order to well understand the role of nano-structured material on dye removal, the adsorbents were characterized through X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy and Brunauer-Emmett-Teller surface area measurement. Finally, the analysis clearly demonstrates that the dye removal onto prepared adsorbent is well fitted with Langmuir isotherm compared to the other isotherm models. The low cost of material and facile process support the further development for commercial application purpose. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Optimizing adsorption of blue pigment from wastewater by nano-porous modified Na-bentonite using spectrophotometry based on response surface method

    Science.gov (United States)

    Moradi, Neshat; Salem, Shiva; Salem, Amin

    2018-03-01

    This work highlighted the effective activation of bentonite paste to produce nano-porous powder for removal of cationic dye from wastewater. The effects of activation parameters such as soda and moisture contents, ageing time and temperature were analyzed using response surface methodology (RSM). The significance of independent variables and their interactions were tested by blending the obtained powders with wastewater and then the adsorption was evaluated, spectrophotometrically. The experiments were carried out by preparation of pastes according to response surface methodology and central composite design, which is the standard method, was used to evaluate the effects and interactions of four factors on the treatment efficiency. RSM was demonstrated as an appropriate approach for optimization of alkali activation. The optimal conditions obtained from the desirable responses were 5.0 wt% soda and 45.0 wt% moisture, respectively in which the powder activation was carried out at 150 °C. In order to well understand the role of nano-structured material on dye removal, the adsorbents were characterized through X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy and Brunauer-Emmett-Teller surface area measurement. Finally, the analysis clearly demonstrates that the dye removal onto prepared adsorbent is well fitted with Langmuir isotherm compared to the other isotherm models. The low cost of material and facile process support the further development for commercial application purpose.

  15. Physicochemical properties and in vitro cytocompatibility of modified titanium surfaces prepared via micro-arc oxidation with different calcium concentrations

    International Nuclear Information System (INIS)

    Wu, Sui-Dan; Zhang, Hui; Dong, Xu-Dong; Ning, Cheng-Yun; Fok, Alex S.L.; Wang, Yan

    2015-01-01

    Highlights: • MAO coating improves the surface characteristics and cytocompatibility of titanium. • Composition of MAO coating varies with the electrolyte concentration. • MAO coating properties can be optimized by adjusting the electrolyte concentration. • Higher CA concentration contributes to more favorable MAO coating cytocompatibility. - Abstract: Objective: To explore the effect of calcium concentration in the electrolyte solution on the physicochemical properties and biocompatibility of coatings formed by micro-arc oxidation (MAO) on titanium surfaces. Methods: The surfaces of pure titanium plates were modified by MAO in an electrolytic solution containing calcium acetate (CA; C 4 H 6 CaO 4 ) at concentrations of 0.05, 0.1, 0.2, or 0.3 M and β-glycerophosphate disodium salt pentahydrate (β-GP; C 3 H 7 Na 2 O 6 P·5H 2 O) at a fixed concentration of 0.02 M. Surface topography, elemental characteristics, phase composition, and roughness were investigated by scanning electron microscopy, energy-dispersive X-ray analysis, X-ray diffraction, and a surface roughness tester, respectively. To assess the cytocompatibility and osteoinductivity of the surfaces, MC3T3-E1 preosteoblasts were cultured on the surfaces in vitro, and cell morphology, adhesion, proliferation, and differentiation were observed. Results: The porous MAO coating was composed primarily of TiO 2 rutile and anatase. The amount of TiO 2 rutile, the Ca/P ratio, and the surface roughness of the MAO coating increased with increasing CA concentration in the electrolyte solution. Ca 3 (PO 4 ) 2 , CaCO 3 , and CaTiO 3 were formed on MAO-treated surfaces prepared with CA concentrations of 0.2 and 0.3 M. Cell proliferation and differentiation increased with increasing CA concentration, with MC3T3-E1 cells exhibiting favorable morphologies for bone–implant integration. Conclusions: MAO coating improves the surface characteristics and cytocompatibility of titanium for osseointegration. Higher CA

  16. Physicochemical properties and in vitro cytocompatibility of modified titanium surfaces prepared via micro-arc oxidation with different calcium concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Sui-Dan; Zhang, Hui [Guanghua School of Stomatology, Hospital of Stomatology, Guangdong Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055 (China); Dong, Xu-Dong [Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, BC V6T 1Z3 (Canada); Ning, Cheng-Yun [College of Material Science and Engineering, South China University of Technology, Guangzhou 510641 (China); Fok, Alex S.L. [Minnesota Dental Research Center of Biomaterials and Biomechanics, School of Dentistry, University of Minnesota, Minneapolis, MN 55414 (United States); Wang, Yan, E-mail: wyan65@163.com [Guanghua School of Stomatology, Hospital of Stomatology, Guangdong Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055 (China)

    2015-02-28

    Highlights: • MAO coating improves the surface characteristics and cytocompatibility of titanium. • Composition of MAO coating varies with the electrolyte concentration. • MAO coating properties can be optimized by adjusting the electrolyte concentration. • Higher CA concentration contributes to more favorable MAO coating cytocompatibility. - Abstract: Objective: To explore the effect of calcium concentration in the electrolyte solution on the physicochemical properties and biocompatibility of coatings formed by micro-arc oxidation (MAO) on titanium surfaces. Methods: The surfaces of pure titanium plates were modified by MAO in an electrolytic solution containing calcium acetate (CA; C{sub 4}H{sub 6}CaO{sub 4}) at concentrations of 0.05, 0.1, 0.2, or 0.3 M and β-glycerophosphate disodium salt pentahydrate (β-GP; C{sub 3}H{sub 7}Na{sub 2}O{sub 6}P·5H{sub 2}O) at a fixed concentration of 0.02 M. Surface topography, elemental characteristics, phase composition, and roughness were investigated by scanning electron microscopy, energy-dispersive X-ray analysis, X-ray diffraction, and a surface roughness tester, respectively. To assess the cytocompatibility and osteoinductivity of the surfaces, MC3T3-E1 preosteoblasts were cultured on the surfaces in vitro, and cell morphology, adhesion, proliferation, and differentiation were observed. Results: The porous MAO coating was composed primarily of TiO{sub 2} rutile and anatase. The amount of TiO{sub 2} rutile, the Ca/P ratio, and the surface roughness of the MAO coating increased with increasing CA concentration in the electrolyte solution. Ca{sub 3}(PO{sub 4}){sub 2}, CaCO{sub 3}, and CaTiO{sub 3} were formed on MAO-treated surfaces prepared with CA concentrations of 0.2 and 0.3 M. Cell proliferation and differentiation increased with increasing CA concentration, with MC3T3-E1 cells exhibiting favorable morphologies for bone–implant integration. Conclusions: MAO coating improves the surface characteristics and

  17. Distribution of 210Pb activity concentrations in marine surface sediments within East Coast Peninsula Malaysia Exclusive Economic Zone (EEZ)

    International Nuclear Information System (INIS)

    Ahmad Sanadi Abu Bakar; Zaharudin Ahmad

    2010-01-01

    A sampling expedition into the East Coast Peninsula Malaysia Exclusive Economic Zone (EEZ) was carried in June 2008. Marine surface sediment samples were taken and the activity concentrations of 210 Pb have been determined. Its distribution was plotted and the findings show that the activity concentrations decline from north to south. On the other hand, the activity concentrations are increasing from west to east right to the edge of the EEZ. The highest activity concentrations were found to be near offshore oil platforms. The 210 Pb activity concentrations were found to be in the range of 18.3 - 123.1 Bq/ kg. (author)

  18. Pigmented villo nodular synovitis

    Directory of Open Access Journals (Sweden)

    Radha S

    2006-01-01

    Full Text Available Background: Pigmented villonodular synovitis is a rare disorder affecting joints. Methods : We reviewed 19 cases of pigmented villonodular synovitis out of 481 arthroscopic synovial biopsies over a period of ten years. A common presenting symptom was locking. Both diffuse and localized forms were diagnosed. Duration of symptoms varied from 5 months to3 years. We report our experience of patients treated by arthroscopic excision for localized villonodular synovitis and arthroscopic synovectomy for diffuse villonodular synovitis followed by intraarticular Yttrium. Results : In diffuse villonodular synovitis arthroscopic total synovectomy was done a using special angular and straight motorized shaver through different portals to reach all corners of the joint. Localized variety was treated by excising the pedicle attached to the synovium. In our series none of the patients with localized villonodular synovitis showed recurrence till date. Three cases of diffuse variety presented with effusion and swelling three to six months after treatment and were managed by arthoscopic synovial shaving. Two cases who showed recurrence after one year were subjected to intraarticular 90Y isotope injection. Conclusion : Arthroscopic synovectomy helps in reducing morbidity. Radiation and intraarticular Injection of 90 Y are alternative modes of treatment.

  19. Measuring variation of indoor radon concentration using bare nuclear tracks detectors, scintillation counters and surface barrier detectors

    International Nuclear Information System (INIS)

    Ishak, I.; Mahat, R.H.; Amin, Y.M.

    1996-01-01

    Bare LRI 15 nuclear track detectors , scintillators counter and surface barrier detectors were used to measured the indoor radon concentration in various location within two rooms. Spatial variation of the radon concentration is caused by positioning of the door, windows, furniture, cracks in the building and also distances from floor, wall and ceiling. It is found that the change in temperature are causing radon concentration to increase at certain time of the day

  20. Optimizing Angkak Pigments and Lovastatin Production By Monascus purpureus

    Directory of Open Access Journals (Sweden)

    HASIM DANURI

    2008-06-01

    Full Text Available Angkak pigments and lovastatin had been reported very useful as natural coloring agents, as an agent to increase thrombocyte level in Dengue hemorrhagic fever, and also as a compound that was able to control blood cholesterol level. Three strains of fungus Monascus purpureus AKI, AKII, and 915 were selected to produce angkak pigments and lovastatin in potato dextrose agar (PDA medium. The best fungus strain, which is AKII, was then applied in three kinds of rice media (white rice IR-42, red rice BP-1804-IF-9, and a combination of 1:1 (w/w white IR-42 and red rice BP-1804-IF-9 for solid fermentation. The best medium and fermentation times were determined for the production of angkak pigments and lovastatin separately. Results showed that strains, media, and duration of fermentations gave significant effect on the amount of pigment produced. Strain AKII produced highest concentration of angkak pigments. The combination of rice (White IR-42 and red rice BP-1804-IF-9 produced the highest pigment than the individual white and red rie it self. The optimum duration of fermentation was 16 days for strains AKI and AKII, but only 15 days for strain 915. Therefore the strain AKII with media combination of rice and a fermentation time of 16 days were used to investigate the additional effect of various minerals. Addition of the mineral individually gave significant increased on angkak pigment production by AKII, where as the addition of minerals mixture in the forth tube did not.

  1. Monitoring of nutrients concentration in surface waters of small mid-field water bodies in agricultural watershed

    Directory of Open Access Journals (Sweden)

    Katarzyna Ligocka

    2018-04-01

    Full Text Available Studies were conducted on surface waters of mid-field ponds in agricultural watershed. The resarch were aimed to perform introductory assessment of ammoniacal nitrogen's and nitric nitrogen's aswell as phosphates concentrations in surface waters. The studies have been performed from March to October, 2015 to 2017. The highest concentration of phosphates were detected in year 2017, whereas the highest concentrations of these were experienced in June in every year. The lowest concentration of phosphates were detected in the first year of studies (2015. The average concentration of phosphate got higher every year. Phosphates' concentrations got higher from March to October, however, the decline were experienced in later period. Conducted research confirmed the dependence, that in lower temperatures the concentrations of ammonia cal nitrogen were generally lower than in the months with higher average temperature. The highest average concentration of ammonia cal nitrogen (0,29 mg•kg -1 was detected in the first year of studies (2015. Average concentrations of nitric nitrogen’s fluctuates from from 0,15 to 0,24 mg•kg -1 . In every year, the concentrations of nitrates were highest in June. The lowest concentrations of nitrates in 2015 and 2016 were experienced in August, and in July of 2017.

  2. Fractional-Slot Surface Mounted PM Motors with Concentrated Windings for HEV Traction Drives

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, J.M.

    2005-10-24

    High-power density and efficiency resulting from elimination of rotor windings and reduced magnetic-flux losses have made the rare earth permanent magnet (PM) motor a leading candidate for the Department of Energy's Office of FreedomCAR and Vehicle Technologies (FCVTs) traction drive motor. These traction drives are generally powered by radial-gap motors, having the magnets on or embedded in a rotating cylinder separated from the inside surface of a slotted cylindrical stator by an annular gap. The two main types of radial-gap PM rotors are those with magnets mounted on the surface of a supporting back iron, called PM surface mounted (PMSM) motors, and those with magnets mounted in slots in the rotor, called interior PM (IPM) motors. Most early PM motor research was on the PMSM motor, which was thought to have an inherently low stator inductance. A low stator inductance can lead to currents dangerously exceeding rated current as the back-emf across the inductance increases with speed; consequently, part of the attempted solution has been to increase the stator inductance to reduce the rate of current rise. Although analysis suggested that there should be no problem designing sufficiently high stator inductance into PMSMs, attempts to do so were often not successful and a motor design was sought that would have a higher intrinsic inductance. Commercial research at Toyota has focused on IPM motors because they can achieve a high-saliency ratio, which helps them operate over a high constant power speed ratio (CPSR), but they are more difficult to fabricate. The Oak Ridge National Laboratory's (ORNL) position has been to continue research on brushless direct current (dc) motors (BDCMs) because of ease of fabrication and increased power output. Recently there has been a revival of interest in a fractional-slot PMSMs [15] made with concentrated windings because they possess three important features. First, they can increase the motor's inductance

  3. Estimation of Phytoplankton Accessory Pigments From Hyperspectral Reflectance Spectra: Toward a Global Algorithm

    Science.gov (United States)

    Chase, A. P.; Boss, E.; Cetinić, I.; Slade, W.

    2017-12-01

    Phytoplankton community composition in the ocean is complex and highly variable over a wide range of space and time scales. Able to cover these scales, remote-sensing reflectance spectra can be measured both by satellite and by in situ radiometers. The spectral shape of reflectance in the open ocean is influenced by the particles in the water, mainly phytoplankton and covarying nonalgal particles. We investigate the utility of in situ hyperspectral remote-sensing reflectance measurements to detect phytoplankton pigments by using an inversion algorithm that defines phytoplankton pigment absorption as a sum of Gaussian functions. The inverted amplitudes of the Gaussian functions representing pigment absorption are compared to coincident High Performance Liquid Chromatography measurements of pigment concentration. We determined strong predictive capability for chlorophylls a, b, c1+c2, and the photoprotective carotenoids. We also tested the estimation of pigment concentrations from reflectance-derived chlorophyll a using global relationships of covariation between chlorophyll a and the accessory pigments. We found similar errors in pigment estimation based on the relationships of covariation versus the inversion algorithm. An investigation of spectral residuals in reflectance data after removal of chlorophyll-based average absorption spectra showed no strong relationship between spectral residuals and pigments. Ultimately, we are able to estimate concentrations of three chlorophylls and the photoprotective carotenoid pigments, noting that further work is necessary to address the challenge of extracting information from hyperspectral reflectance beyond the information that can be determined from chlorophyll a and its covariation with other pigments.

  4. Localization and seasonal variation of blue pigment (sandercyanin) in walleye (Sander vitreus)

    Science.gov (United States)

    Schaefer, Wayne; Schmitz, Mark; Blazer, Vicki S.; Ehlinger, Tim; Berges, John

    2015-01-01

    Several fish species, including the walleye (Sander vitreus), have “yellow” and “blue” color morphs. In S. vitreus, one source of the blue color has been identified as a bili-binding protein pigment (sandercyanin), found in surface mucus of the fish. Little is known about the production of the pigment or about its functions. We examined the anatomical localization and seasonal variation of sandercyanin in S. vitreus from a population in McKim Lake, northwestern Ontario, Canada. Skin sections were collected from 20 fish and examined histologically. Mucus was collected from 306 fish over 6 years, and the amount of sandercyanin was quantified spectrophotometrically. Sandercyanin was found solely on dorsal surfaces of the fish and was localized to novel cells in the epidermis, similar in appearance to secretory sacciform cells. Sandercyanin concentrations were significantly higher in fish collected in summer versus other seasons. Yellow and blue morphs did not differ in amounts of sandercyanin, suggesting that the observed blue color, in fact, arises from lack of yellow pigmentation in blue morphs. The function of the sandercyanin remains unclear, but roles in photoprotection and countershading are consistent with available data.

  5. Modulation of ATP/ADP concentration at the endothelial surface by shear stress: effect of flow recirculation.

    Science.gov (United States)

    Choi, Hyo Won; Ferrara, Katherine W; Barakat, Abdul I

    2007-04-01

    The extracellular presence of the adenine nucleotides ATP and ADP induces calcium mobilization in vascular endothelial cells (ECs). ATP/ADP concentration at the EC surface is determined by a balance of convective-diffusive transport to and from the EC surface, hydrolysis by ectonucleotidases at the cell surface, and flow-induced ATP release from ECs. Our previous numerical simulations in a parallel plate geometry had demonstrated that flow-induced ATP release has a profound effect on nucleotide concentration at the EC surface. In the present study, we have extended the modeling to probe the impact of flow separation and recirculation downstream of a backward facing step (BFS) on ATP/ADP concentration at the EC surface. The results show that for both steady and pulsatile flow over a wide range of wall shear stresses, the ATP+ADP concentration at the EC surface is considerably lower within the flow recirculation region than in areas of undisturbed flow outside the recirculation zone. Pulsatile flow also leads to sharp temporal gradients in nucleotide concentration. If confirmed experimentally, the present findings suggest that disturbed and undisturbed flow may affect EC calcium mobilization differently. Such differences might, in turn, contribute to the observed endothelial dysfunction in regions of disturbed flow.

  6. Coral Pigments: Quantification Using HPLC and Detection by Remote Sensing

    Science.gov (United States)

    Cottone, Mary C.

    1995-01-01

    Widespread coral bleaching (loss of pigments of symbiotic dinoflagellates), and the corresponding decline in coral reef health worldwide, mandates the monitoring of coral pigmentation. Samples of the corals Porites compressa and P. lobata were collected from a healthy reef at Puako, Hawaii, and chlorophyll (chl) a, peridinin, and Beta-carotene (Beta-car) were quantified using reverse-phase high performance liquid chromatography (HPLC). Detailed procedures are presented for the extraction of the coral pigments in 90% acetone, and the separation, identification, and quantification of the major zooxanthellar pigments using spectrophotometry and a modification of the HPLC system described by Mantoura and Llewellyn (1983). Beta-apo-8-carotenal was found to be inadequate as in internal standard, due to coelution with chl b and/or chl a allomer in the sample extracts. Improvements are suggested, which may result in better resolution of the major pigments and greater accuracy in quantification. Average concentrations of peridinin, chl a, and Beta-car in corals on the reef were 5.01, 8.59, and 0.29, micro-grams/cm(exp 2), respectively. Average concentrations of peridinin and Beta-car did not differ significantly between the two coral species sampled; however, the mean chl a concentration in P. compressa specimens (7.81 ,micro-grams/cm(exp 2) was significantly lower than that in P. lobata specimens (9.96 11g/cm2). Chl a concentrations determined spectrophotometrically were significantly higher than those generated through HPLC, suggesting that spectrophotometry overestimates chl a concentrations. The average ratio of chl a-to-peridinin concentrations was 1.90, with a large (53%) coefficient of variation and a significant difference between the two species sampled. Additional data are needed before conclusions can be drawn regarding average pigment concentrations in healthy corals and the consistency of the chl a/peridinin ratio. The HPLC pigment concentration values

  7. Distribution of Mercury Concentrations in Tree Rings and Surface Soils Adjacent to a Phosphate Fertilizer Plant in Southern Korea.

    Science.gov (United States)

    Jung, Raae; Ahn, Young Sang

    2017-08-01

    This study aimed to determine mercury concentrations in tree rings and surface soils at distances of 4, 26 and 40 km from a fertilizer plant located in Yeosu City, Korea. Mercury concentrations in all tree rings were low prior to the establishment of the plant in 1977 and became elevated thereafter. The highest average mercury concentration in the tree rings was 11.96 ng g -1 at the Yeosu site located nearest to the plant, with the lowest average mercury concentration of 4.45 ng g -1 at the Suncheon site furthest away from the plant. In addition, the highest mercury content in the surface soil was 108.51 ng cm -3 at the Yeosu site, whereas the lowest mercury content in the surface soil was 31.47 ng cm -3 at the Suncheon site. The mercury levels decreased gradually with increasing distance from the plant.

  8. Quantitative estimation of hydrogen concentration on the Ni3Al specimens surface in the process of hydrogen release

    International Nuclear Information System (INIS)

    Katano, Gen; Sano, Shogo; Saito, Hideo; Mori, Minoru

    2000-01-01

    The method to calculate the hydrogen concentration in metal specimens is given by tritium counts with the liquid scintillation counter. As segments to measure, Ni 3 Al intermetallic compound crystals were used. Tritium was charged to crystals with the method of cathode charging. The charged tritium was transported by diffusion and released from specimen surface. The tritium releasing rate was calculated from the increasing rate of tritium activity. Then the concentration of hydrogen at the surface was calculated from tritium counts. The outcome showed that the hydrogen concentration decreases at specimens surface by elapsed time. Then, the behavior of tritium diffusion was affected by doped boron (up to 0.235 atom% B and 0.470 atom% B) in Ni 3 Al crystals. As the amount of boron increased, the tritium diffusion coefficient decreased. And the hydrogen concentration varied with the amount of boron. After passing enough time, the hydrogen concentration in crystals with boron was much larger than the one without boron. Since it is very likely that the hydrogen concentration is affected by the number of hydrogen sites in the crystal, it is obvious judging by these phenomena, that by doping boron, numbers of hydrogen trapping sites were created. As the hydrogen distribution becomes homogenous after passing enough time, it is possible to measure the hydrogen concentration in all the crystals from β-ray counts at specimens surface. (author)

  9. Metal concentrations in surface water and sediments from Pardo River, Brazil: human health risks.

    Science.gov (United States)

    Alves, Renato I S; Sampaio, Carolina F; Nadal, Martí; Schuhmacher, Marta; Domingo, José L; Segura-Muñoz, Susana I

    2014-08-01

    Pardo River (Brazil) is suffering from an important anthropogenic impact due to the pressure of highly populated areas and the influence of sugarcane cultivation. The objective of the present study was to determine the levels of 13 trace elements (As, Be, Cd, Cr, Cu, Pb, Mn, Hg, Ni, Tl, Sn, V and Zn) in samples of surface water and sediments from the Pardo River. Furthermore, the human health risks associated with exposure to those metals through oral intake and dermal absorption were also evaluated. Spatial and seasonal trends of the data were closely analyzed from a probabilistic approach. Manganese showed the highest mean concentrations in both water and sediments, remarking the incidence of the agricultural activity and the geological characteristics within the basin. Thallium and arsenic were identified as two priority pollutants, being the most important contributors to the Hazard Index (HI). Since non-carcinogenic risks due to thallium exposure slightly exceeded international guidelines (HI>1), a special effort should be made on this trace element. However, the current concentrations of arsenic, a carcinogenic element, were in accordance to acceptable lifetime risks. Nowadays, there is a clear increasing growth in human population and economic activities in the Pardo River, whose waters have become a serious strategic alternative for the potential supply of drinking water. Therefore, environmental monitoring studies are required not only to assure that the current state of pollution of Pardo River does not mean a risk for the riverside population, but also to assess the potential trends in the environmental levels of those elements. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Rapid Adjustments Cause Weak Surface Temperature Response to Increased Black Carbon Concentrations

    Science.gov (United States)

    Stjern, Camilla Weum; Samset, Bjørn Hallvard; Myhre, Gunnar; Forster, Piers M.; Hodnebrog, Øivind; Andrews, Timothy; Boucher, Olivier; Faluvegi, Gregory; Iversen, Trond; Kasoar, Matthew; Kharin, Viatcheslav; Kirkevâg, Alf; Lamarque, Jean-François; Olivié, Dirk; Richardson, Thomas; Shawki, Dilshad; Shindell, Drew; Smith, Christopher J.; Takemura, Toshihiko; Voulgarakis, Apostolos

    2017-11-01

    We investigate the climate response to increased concentrations of black carbon (BC), as part of the Precipitation Driver Response Model Intercomparison Project (PDRMIP). A tenfold increase in BC is simulated by nine global coupled-climate models, producing a model median effective radiative forcing of 0.82 (ranging from 0.41 to 2.91) W m-2, and a warming of 0.67 (0.16 to 1.66) K globally and 1.24 (0.26 to 4.31) K in the Arctic. A strong positive instantaneous radiative forcing (median of 2.10 W m-2 based on five of the models) is countered by negative rapid adjustments (-0.64 W m-2 for the same five models), which dampen the total surface temperature signal. Unlike other drivers of climate change, the response of temperature and cloud profiles to the BC forcing is dominated by rapid adjustments. Low-level cloud amounts increase for all models, while higher-level clouds are diminished. The rapid temperature response is particularly strong above 400 hPa, where increased atmospheric stabilization and reduced cloud cover contrast the response pattern of the other drivers. In conclusion, we find that this substantial increase in BC concentrations does have considerable impacts on important aspects of the climate system. However, some of these effects tend to offset one another, leaving a relatively small median global warming of 0.47 K per W m-2—about 20% lower than the response to a doubling of CO2. Translating the tenfold increase in BC to the present-day impact of anthropogenic BC (given the emissions used in this work) would leave a warming of merely 0.07 K.

  11. Kernel density surface modelling as a means to identify significant concentrations of vulnerable marine ecosystem indicators.

    Directory of Open Access Journals (Sweden)

    Ellen Kenchington

    Full Text Available The United Nations General Assembly Resolution 61/105, concerning sustainable fisheries in the marine ecosystem, calls for the protection of vulnerable marine ecosystems (VME from destructive fishing practices. Subsequently, the Food and Agriculture Organization (FAO produced guidelines for identification of VME indicator species/taxa to assist in the implementation of the resolution, but recommended the development of case-specific operational definitions for their application. We applied kernel density estimation (KDE to research vessel trawl survey data from inside the fishing footprint of the Northwest Atlantic Fisheries Organization (NAFO Regulatory Area in the high seas of the northwest Atlantic to create biomass density surfaces for four VME indicator taxa: large-sized sponges, sea pens, small and large gorgonian corals. These VME indicator taxa were identified previously by NAFO using the fragility, life history characteristics and structural complexity criteria presented by FAO, along with an evaluation of their recovery trajectories. KDE, a non-parametric neighbour-based smoothing function, has been used previously in ecology to identify hotspots, that is, areas of relatively high biomass/abundance. We present a novel approach of examining relative changes in area under polygons created from encircling successive biomass categories on the KDE surface to identify "significant concentrations" of biomass, which we equate to VMEs. This allows identification of the VMEs from the broader distribution of the species in the study area. We provide independent assessments of the VMEs so identified using underwater images, benthic sampling with other gear types (dredges, cores, and/or published species distribution models of probability of occurrence, as available. For each VME indicator taxon we provide a brief review of their ecological function which will be important in future assessments of significant adverse impact on these habitats here

  12. New directions in phthalocyanine pigments

    Science.gov (United States)

    Trinh, Diep VO

    1994-01-01

    Phthalocyanines have been used as a pigment in coatings and related applications for many years. These pigments are some of the most stable organic pigments known. The phthalo blue and green pigments have been known to be ultraviolet (UV) stable and thermally stable to over 400 C. These phthalocyanines are both a semiconductor and photoconductor, exhibiting catalytic activity and photostabilization capability of polymers. Many metal free and metallic phthalocyanine derivatives have been prepared. Development of the new classes of phthalocyanine pigment could be used as coating on NASA spacecraft material such as glass to decrease the optical degradation from UV light, the outside of the space station modules for UV protection, and coating on solar cells to increase lifetime and efficiency.

  13. Ozone Sensitivity and Catalase Activity in Pigmented and Non-Pigmented Strains of Serratia Marcescens

    Science.gov (United States)

    de Ondarza, José

    2017-01-01

    Background: Ozone exposure rapidly leads to bacterial death, making ozone an effective disinfectant in food industry and health care arena. However, microbial defenses may moderate this effect and play a role in the effective use of oxidizing agents for disinfection. Serratia marcescens is an opportunistic pathogen, expressing genes differentially during infection of a human host. A better understanding of regulatory systems that control expression of Serratia’s virulence genes and defenses is therefore valuable. Objective: Here, we investigated the role of pigmentation and catalase in Serratia marcescens on survival to ozone exposure. Method: Pigmented and non-pigmented strains of Serratia marcescens were cultured to exponential or stationary phase and exposed to 5 ppm of gaseous ozone for 2.5 – 10 minutes. Survival was calculated via plate counts. Catalase activity was measured photometrically and tolerance to hydrogen peroxide was assayed by disk-diffusion. Results: Exposure of S. marcescens to 5 ppm gaseous ozone kills > 90% of cells within 10 minutes in a time and concentration-dependent manner. Although pigmented Serratia (grown at 28°C) survived ozonation better than unpigmented Serratia (grown at 35°C), non-pigmented mutant strains of Serratia had similar ozone survival rates, catalase activity and H2O2 tolerance as wild type strains. Rather, ozone survival and catalase activity were elevated in 6 hour cultures compared to 48 hour cultures. Conclusion: Our studies did not bear out a role for prodigiosin in ozone survival. Rather, induction of oxidative stress responses during exponential growth increased both catalase activity and ozone survival in both pigmented and unpigmented S. marcescens. PMID:28567147

  14. Ozone Sensitivity and Catalase Activity in Pigmented and Non-Pigmented Strains of Serratia Marcescens.

    Science.gov (United States)

    de Ondarza, José

    2017-01-01

    Ozone exposure rapidly leads to bacterial death, making ozone an effective disinfectant in food industry and health care arena. However, microbial defenses may moderate this effect and play a role in the effective use of oxidizing agents for disinfection. Serratia marcescens is an opportunistic pathogen, expressing genes differentially during infection of a human host. A better understanding of regulatory systems that control expression of Serratia 's virulence genes and defenses is therefore valuable. Here, we investigated the role of pigmentation and catalase in Serratia marcescens on survival to ozone exposure. Pigmented and non-pigmented strains of Serratia marcescens were cultured to exponential or stationary phase and exposed to 5 ppm of gaseous ozone for 2.5 - 10 minutes. Survival was calculated via plate counts. Catalase activity was measured photometrically and tolerance to hydrogen peroxide was assayed by disk-diffusion. Exposure of S. marcescens to 5 ppm gaseous ozone kills > 90% of cells within 10 minutes in a time and concentration-dependent manner. Although pigmented Serratia (grown at 28°C) survived ozonation better than unpigmented Serratia (grown at 35°C), non-pigmented mutant strains of Serratia had similar ozone survival rates, catalase activity and H 2 O 2 tolerance as wild type strains. Rather, ozone survival and catalase activity were elevated in 6 hour cultures compared to 48 hour cultures. Our studies did not bear out a role for prodigiosin in ozone survival. Rather, induction of oxidative stress responses during exponential growth increased both catalase activity and ozone survival in both pigmented and unpigmented S. marcescens .

  15. Metallographic examination of hardened layers after surface treatments by highly concentrated plasma jet

    Directory of Open Access Journals (Sweden)

    Сергій Савелійович Самотугін

    2017-07-01

    Full Text Available The microstructure of carbon and alloy steels with various carbon contents before and after the gradient hardening by means of highly concentrated plasma jet have been investigated. It is shown that the resulting structure after the surface hardening has a substantially smaller grain size as compared to the bulk hardening. The steels with different carbon content, that is hypoeutectic steels 45 and 50HN, eutectic steels – M76, U8, hypereutectoid steels – 90HF, U10 have been researched. Processing was carried out under the optimal conditions to ensure the highest hardness of the surface without melting. Metalgraphical studies were carried out using optical and scanning electron microscopes. High-dispersed martensite is the main structural component for hypoeutectic steels. Despite the fact that the heating temperature and the cooling rate in different parts of the plasma exposure zone differ greatly, the structure of the tempered zone is uniform by both the degree of dispersion and by the values of hardness. Plasma treatment of eutectic steels results in fine-grained structure of martensite of mainly lamellar morphology. High-dispersed martensite with microparticles of secondary carbides is characteristic of the hardened zones for hypereutectic steels. But austenite grains do not grow at heating as it usually happens in bulk hardening. The structure of the transition zone corresponds to part-hardened steels. So excess ferrite as well as martensite retains in hypoeutectic steels while excess cementite retains in hypereutectic steels. Eutectic steels are free from the intercritical interval, and the transition zone does not practically develop, there being a very sharp boundary between the zone of full hardening and the parent metal. Due to this structure of the plasma hardening zone of the surface layer there arises 3,5...4,5-fold increase in the hardness of the steel as compared with the normalized condition. This is due to the increase in

  16. Effect of different concentrations of sodium hyaluronate on the ocular surface change of dry eye in New Zealand rabbits

    Directory of Open Access Journals (Sweden)

    Shuang-Yong Wang

    2015-10-01

    Full Text Available AIM:To observe the effect of different concentrations of sodium hyaluronate on ocular surface change of dry eye. METHODS: New Zealand rabbits with dry eye was prepared and treated with 0.1% and 0.3% sodium hyaluronate drops fluid respectively, which were regarded as low concentration treatment group(group Band high concentration treatment group(group Crespectively. However, the rabbits treated with saline were regarded as control group(group A. And then, corneal fluorescein staining, Schirmer test, conjunctival goblet cells, mucin expression and histological changes were observed.RESULTS: On D7 and D14 after treatment, corneal fluorescein staining scores were lower in group B and group C than that in group A(PP PCONCLUSION: The sodium hyaluronate can improve ocular surface damage of dry eye in New Zealand rabbits. The high concentration of sodium hyaluronate has better effect than low concentration.

  17. Effect of energy source, salt concentration and loading force on colloidal interactions between Acidithiobacillus ferrooxidans cells and mineral surfaces.

    Science.gov (United States)

    Diao, Mengxue; Nguyen, Tuan A H; Taran, Elena; Mahler, Stephen M; Nguyen, Anh V

    2015-08-01

    The surface appendages and extracellular polymeric substances of cells play an important role in the bacterial adhesion process. In this work, colloidal forces and nanomechanical properties of Acidithiobacillus ferrooxidans (A. f) interacted with silicon wafer and pyrite (FeS2) surfaces in solutions of varying salt concentrations were quantitatively examined using the bacterial probe technique with atomic force microscopy. A. f cells were cultured with either ferrous sulfate or elemental sulfur as key energy sources. Our results show that A. f cells grown with ferrous ion and elemental sulfur exhibit distinctive retraction force vs separation distance curves with stair-step and saw tooth shapes, respectively. During the approach of bacterial probes to the substrate surfaces, surface appendages and biopolymers of cells are sequentially compressed. The conformations of surface appendages and biopolymers are significantly influenced by the salt concentrations. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. The effect of different fiber concentrations on the surface roughness of provisional crown and fixed partial denture resin.

    Science.gov (United States)

    Zortuk, Mustafa; Kılıc, Kerem; Uzun, Gulay; Ozturk, Ahmet; Kesim, Bulent

    2008-07-01

    The aim of this study was to investigate surface roughness in provisional crown acrylics, after polishing, reinforced with different concentrations of glass fibers. A total of 48 disk-shaped specimens were prepared using autopolymerizing acrylic resin. These specimens were divided into four groups according to the level of glass fiber added: Group A (no fiber), Group B (0.5%), Group C (1%) and Group D (2%). After polishing the specimens, an average surface roughness (Ra) value was calculated using a profilometer from four randomly selected points on the surface. A significant difference was determined among the surface roughness values of provisional crown resins to which different concentrations of fiber had been added (Pprovisional crown and fixed partial denture resin with glass fibers increases surface roughness.

  19. Integration of Multiplexed Microfluidic Electrokinetic Concentrators with a Morpholino Microarray via Reversible Surface Bonding for Enhanced DNA Hybridization.

    Science.gov (United States)

    Martins, Diogo; Wei, Xi; Levicky, Rastislav; Song, Yong-Ak

    2016-04-05

    We describe a microfluidic concentration device to accelerate the surface hybridization reaction between DNA and morpholinos (MOs) for enhanced detection. The microfluidic concentrator comprises a single polydimethylsiloxane (PDMS) microchannel onto which an ion-selective layer of conductive polymer poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) ( PSS) was directly printed and then reversibly surface bonded onto a morpholino microarray for hybridization. Using this electrokinetic trapping concentrator, we could achieve a maximum concentration factor of ∼800 for DNA and a limit of detection of 10 nM within 15 min. In terms of the detection speed, it enabled faster hybridization by around 10-fold when compared to conventional diffusion-based hybridization. A significant advantage of our approach is that the fabrication of the microfluidic concentrator is completely decoupled from the microarray; by eliminating the need to deposit an ion-selective layer on the microarray surface prior to device integration, interfacing between both modules, the PDMS chip for electrokinetic concentration and the substrate for DNA sensing are easier and applicable to any microarray platform. Furthermore, this fabrication strategy facilitates a multiplexing of concentrators. We have demonstrated the proof-of-concept for multiplexing by building a device with 5 parallel concentrators connected to a single inlet/outlet and applying it to parallel concentration and hybridization. Such device yielded similar concentration and hybridization efficiency compared to that of a single-channel device without adding any complexity to the fabrication and setup. These results demonstrate that our concentrator concept can be applied to the development of a highly multiplexed concentrator-enhanced microarray detection system for either genetic analysis or other diagnostic assays.

  20. Iris phenotypes and pigment dispersion caused by genes influencing pigmentation.

    Science.gov (United States)

    Anderson, Michael G; Hawes, Norman L; Trantow, Colleen M; Chang, Bo; John, Simon W M

    2008-10-01

    Spontaneous mutations altering mouse coat colors have been a classic resource for discovery of numerous molecular pathways. Although often overlooked, the mouse iris is also densely pigmented and easily observed, thus representing a similarly powerful opportunity for studying pigment cell biology. Here, we present an analysis of iris phenotypes among 16 mouse strains with mutations influencing melanosomes. Many of these strains exhibit biologically and medically relevant phenotypes, including pigment dispersion, a common feature of several human ocular diseases. Pigment dispersion was identified in several strains with mutant alleles known to influence melanosomes, including beige, light, and vitiligo. Pigment dispersion was also detected in the recently arising spontaneous coat color variant, nm2798. We have identified the nm2798 mutation as a missense mutation in the Dct gene, an identical re-occurrence of the slaty light mutation. These results suggest that dysregulated events of melanosomes can be potent contributors to the pigment dispersion phenotype. Combined, these findings illustrate the utility of studying iris phenotypes as a means of discovering new pathways, and re-linking old ones, to processes of pigmented cells in health and disease.

  1. Enhancing Dark Shade Pigment Dyeing of Cotton Fabric Using Plasma Treatment

    Directory of Open Access Journals (Sweden)

    Chi-Wai Kan

    2017-07-01

    Full Text Available This study is intended to investigate the effect of atmospheric pressure plasma treatment on dark shade pigment dyeing of cotton fabric. Experimental results reveal that plasma-treated cotton fabric can attain better color yield, levelness, and crocking fastness in dark shade pigment dyeing, compared with normal cotton fabric (not plasma treated. SEM analysis indicates that cracks and grooves were formed on the cotton fiber surface where the pigment and the binder can get deposited and improve the color yield, levelness, and crocking fastness. It was also noticed that pigment was aggregated when deposited on the fiber surface which could affect the final color properties.

  2. Pteropods are excellent recorders of surface temperature and carbonate ion concentration.

    Science.gov (United States)

    Keul, N; Peijnenburg, K T C A; Andersen, N; Kitidis, V; Goetze, E; Schneider, R R

    2017-10-03

    Pteropods are among the first responders to ocean acidification and warming, but have not yet been widely explored as carriers of marine paleoenvironmental signals. In order to characterize the stable isotopic composition of aragonitic pteropod shells and their variation in response to climate change parameters, such as seawater temperature, pteropod shells (Heliconoides inflatus) were collected along a latitudinal transect in the Atlantic Ocean (31° N to 38° S). Comparison of shell oxygen isotopic composition to depth changes in the calculated aragonite equilibrium oxygen isotope values implies shallow calcification depths for H. inflatus (75 m). This species is therefore a good potential proxy carrier for past variations in surface ocean properties. Furthermore, we identified pteropod shells to be excellent recorders of climate change, as carbonate ion concentration and temperature in the upper water column have dominant influences on pteropod shell carbon and oxygen isotopic composition. These results, in combination with a broad distribution and high abundance, make the pteropod species studied here, H. inflatus, a promising new proxy carrier in paleoceanography.

  3. Microanalysis study of archaeological mural samples containing Maya blue pigment

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez del Rio, M. [ESRF, BP220, F-38043 Grenoble (France)]. E-mail: srio@esrf.fr; Martinetto, P. [Laboratoire de Cristallographie, CNRS, BP166 F-30842 Grenoble (France); Somogyi, A. [ESRF, BP220, F-38043 Grenoble (France); Reyes-Valerio, C. [INAH, Mexico DF (Mexico); Dooryhee, E. [Laboratoire de Cristallographie, CNRS, BP166 F-30842 Grenoble (France); Peltier, N. [Laboratoire de Cristallographie, CNRS, BP166 F-30842 Grenoble (France); Alianelli, L. [INFM-OGG c/o ESRF, BP220, F-38043 Grenoble Cedex (France); Moignard, B. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France); Pichon, L. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France); Calligaro, T. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France); Dran, J.-C. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France)

    2004-10-08

    Elemental analysis by X-ray fluorescence and particle induced X-ray emission is applied to the study of several Mesoamerican mural samples containing blue pigments. The most characteristic blue pigment is Maya blue, a very stable organo-clay complex original from Maya culture and widely used in murals, pottery and sculptures in a vast region of Mesoamerica during the pre-hispanic time (from VIII century) and during the colonization until 1580. The mural samples come from six different archaeological sites (four pre-hispanic and two from XVI century colonial convents). The correlation between the presence of some elements and the pigment colour is discussed. From the comparative study of the elemental concentration, some conclusions are drawn on the nature of the pigments and the technology used.

  4. Microanalysis study of archaeological mural samples containing Maya blue pigment

    International Nuclear Information System (INIS)

    Sanchez del Rio, M.; Martinetto, P.; Somogyi, A.; Reyes-Valerio, C.; Dooryhee, E.; Peltier, N.; Alianelli, L.; Moignard, B.; Pichon, L.; Calligaro, T.; Dran, J.-C.

    2004-01-01

    Elemental analysis by X-ray fluorescence and particle induced X-ray emission is applied to the study of several Mesoamerican mural samples containing blue pigments. The most characteristic blue pigment is Maya blue, a very stable organo-clay complex original from Maya culture and widely used in murals, pottery and sculptures in a vast region of Mesoamerica during the pre-hispanic time (from VIII century) and during the colonization until 1580. The mural samples come from six different archaeological sites (four pre-hispanic and two from XVI century colonial convents). The correlation between the presence of some elements and the pigment colour is discussed. From the comparative study of the elemental concentration, some conclusions are drawn on the nature of the pigments and the technology used

  5. Surface Tension Estimates for Droplet Formation in Slurries with Low Concentrations of Hydrophobic Particles, Polymer Flocculants or Surface-Active Contaminants

    Energy Technology Data Exchange (ETDEWEB)

    Gauglitz, Phillip A.; Mahoney, Lenna A.; Blanchard, Jeremy; Bamberger, Judith A.

    2011-06-10

    In support of the K-Basin project, Pacific Northwest National Laboratory (PNNL) was requested to evaluate the appropriate surface tension value to use in models predicting the formation of droplets from spray leaks of K-Basin slurries. The specific issue was whether it was more appropriate to use the surface tension of pure water in model predictions for all plausible spray leaks or to use a lower value. The surface tension of K-Basin slurries is potentially affected not only by particles but by low concentrations of nonionic polyacrylamide flocculant and perhaps by contaminants with surfactant properties, which could decrease the surface tension below that of water. A lower surface tension value typically results in smaller droplets being formed with a larger fraction of droplets in the respirable size range, so using the higher surface tension value of pure water is not conservative and thus needs a strong technical basis.

  6. Differences in pigmentation between life cycle stages in Scrippsiella lachrymosa (dinophyceae).

    Science.gov (United States)

    Persson, Agneta; Smith, Barry C; Cyronak, Tyler; Cooper, Emily; DiTullio, Giacomo R

    2016-02-01

    Various life cycle stages of cyst-producing dinoflagellates often appear differently colored under the microscope; gametes appear paler while zygotes are darker in comparison to vegetative cells. To compare physiological and photochemical competency, the pigment composition of discrete life cycle stages was determined for the common resting cyst-producing dinoflagellate Scrippsiella lachrymosa. Vegetative cells had the highest cellular pigment content (25.2 ± 0.5 pg · cell(-1) ), whereas gamete pigment content was 22% lower. The pigment content of zygotes was 82% lower than vegetative cells, even though they appeared darker under the microscope. Zygotes of S. lachrymosa contained significantly higher cellular concentrations of β-carotene (0.65 ± 0.15 pg · cell(-1) ) than all other life stages. Photoprotective pigments and the de-epoxidation ratio of xanthophylls-cycle pigments in S. lachrymosa were significantly elevated in zygotes and cysts compared to other stages. This suggests a role for accessory pigments in combating intracellular oxidative stress during sexual reproduction or encystment. Resting cysts contained some pigments even though chloroplasts were not visible, suggesting that the brightly colored accumulation body contained photosynthetic pigments. The differences in pigmentation between life stages have implications for interpretation of pigment data from field samples when sampled during dinoflagellate blooms. © 2015 Phycological Society of America.

  7. Concentrations of the UV filter ethylhexyl methoxycinnamate in the aquatic compartment: a comparison of modelled concentrations for Swiss surface waters with empirical monitoring data.

    Science.gov (United States)

    Straub, Jürg Oliver

    2002-05-10

    UV filters in sunscreens and cosmetics protect the skin from damage through UV radiation. Many tonnes per year of UV filters are being used in Europe and will be present, at least seasonally, in detectable concentrations in surface waters similar to common pharmaceutically active substances. Predicted environmental concentrations (PECs) of ethylhexyl methoxycinnamate (EHMC; CAS 5466-77-3) were extrapolated for Switzerland, taking into consideration substance-specific environmental fate data and marketing estimates, by crude worst-case reckoning and by applying two environmental models (Mackay Level III; USES 3.0), both configured for Swiss hydrological and area data. By worst-case reckoning the summer PEC is 70.8-81.3 ng/l while for the remaining 8 months of the year the PEC is 13.1-15.1 ng/l. The Level III model results in concentrations of 2.4 ng/l during the summer and 0.44 ng/l during the rest of the year, while the USES 3.0 model gives an average PEC for the whole year of 7.6 ng/l. Pooling summer monitoring data (90 single analyses) from the River Rhine below Basel in the year 1997 (Water Protection Board of Basel) and from Lakes Zurich and Hüttner in 1998 (Poiger et al., in preparation) allowed a derivation of a probabilistic median concentration of 4.6 ng/l, a 95th-percentile concentration of 18.6 ng/l and a 99th-percentile concentration of 33.5 ng/l. The 6-fold range from the median value to the maximum calls for caution in interpreting published monitoring concentrations. Comparison of modelled PECs with realistic median concentrations shows that crude reckoning overestimates actual concentrations by a factor of about 10, probably through insufficient consideration of (further) degradation of EHMC in sewage works, surface waters, sediments or river banks. Both computer models, in contrast, are within the same order of magnitude as the actual summer concentrations. Based on the available data, both these environmental fate and distribution models give

  8. Natural pigments and sacred art

    Science.gov (United States)

    Kelekian, Lena, ,, Lady

    2010-05-01

    Since the dawn of mankind, cavemen has expressed himself through art. The earliest known cave paintings date to some 32,000 years ago and used 4 colours derived from the earth. These pigments were iron oxides and known as ochres, blacks and whites. All pigments known by the Egyptians, the Greeks, the Romans and Renaissance man were natural and it was not until the 18th century that synthetic pigments were made and widely used. Until that time all art, be it sacred or secular used only natural pigments, of which the preparation of many have been lost or rarely used because of their tedious preparation. As a geologist, a mineralogist and an artist specializing in iconography, I have been able to rediscover 89 natural pigments extracted from minerals. I use these pigments to paint my icons in the traditional Byzantine manner and also to restore old icons, bringing back their glamour and conserving them for years to come. The use of the natural pigments in its proper way also helps to preserve the traditional skills of the iconographer. In the ancient past, pigments were extremely precious. Many took an exceedingly long journey to reach the artists, and came from remote countries. Research into these pigments is the work of history, geography and anthropology. It is an interesting journey in itself to discover that the blue aquamarines came from Afghanistan, the reds from Spain, the greens Africa, and so on. In this contribution I will be describing the origins, preparation and use of some natural pigments, together with their history and provenance. Additionally, I will show how the natural pigments are used in the creation of an icon. Being a geologist iconographer, for me, is a sacrement that transforms that which is earthly, material and natural into a thing of beauty that is sacred. As bread and wine in the Eucharist, water during baptism and oil in Holy Union transmit sanctification to the beholder, natural pigments do the same when one considers an icon. The

  9. Spectrophotometric Analysis of Pigments: A Critical Assessment of a High-Throughput Method for Analysis of Algal Pigment Mixtures by Spectral Deconvolution.

    Directory of Open Access Journals (Sweden)

    Jan-Erik Thrane

    Full Text Available The Gauss-peak spectra (GPS method represents individual pigment spectra as weighted sums of Gaussian functions, and uses these to model absorbance spectra of phytoplankton pigment mixtures. We here present several improvements for this type of methodology, including adaptation to plate reader technology and efficient model fitting by open source software. We use a one-step modeling of both pigment absorption and background attenuation with non-negative least squares, following a one-time instrument-specific calibration. The fitted background is shown to be higher than a solvent blank, with features reflecting contributions from both scatter and non-pigment absorption. We assessed pigment aliasing due to absorption spectra similarity by Monte Carlo simulation, and used this information to select a robust set of identifiable pigments that are also expected to be common in natural samples. To test the method's performance, we analyzed absorbance spectra of pigment extracts from sediment cores, 75 natural lake samples, and four phytoplankton cultures, and compared the estimated pigment concentrations with concentrations obtained using high performance liquid chromatography (HPLC. The deviance between observed and fitted spectra was generally very low, indicating that measured spectra could successfully be reconstructed as weighted sums of pigment and background components. Concentrations of total chlorophylls and total carotenoids could accurately be estimated for both sediment and lake samples, but individual pigment concentrations (especially carotenoids proved difficult to resolve due to similarity between their absorbance spectra. In general, our modified-GPS method provides an improvement of the GPS method that is a fast, inexpensive, and high-throughput alternative for screening of pigment composition in samples of phytoplankton material.

  10. Spatial variability of phytoplankton pigment distributions in the Subtropical South Pacific Ocean: comparison between in situ and predicted data

    Directory of Open Access Journals (Sweden)

    J. Ras

    2008-03-01

    Full Text Available In the frame of the BIOSOPE cruise in 2004, the spatial distribution and structure of phytoplankton pigments was investigated along a transect crossing the ultra-oligotrophic South Pacific Subtropical Gyre (SPSG between the Marquesas Archipelago (141° W–8° S and the Chilean upwelling (73° W–34° S. A High Performance Liquid Chromatography (HPLC method was improved in order to be able to accurately quantify pigments over such a large range of trophic levels, and especially from strongly oligotrophic conditions. Seven diagnostic pigments were associated to three phytoplankton size classes (pico-, nano and microphytoplankton. The total chlorophyll-α concentrations [TChlα] in surface waters were the lowest measured in the centre of the gyre, reaching 0.017 mg m−3. Pigment concentrations at the Deep Chlorophyll Maximum (DCM were generally 10 fold the surface values. Results were compared to predictions from a global parameterisation based on remotely sensed surface [TChlα]. The agreement between the in situ and predicted data for such contrasting phytoplankton assemblages was generally good: throughout the oligotrophic gyre system, picophytoplankton (prochlorophytes and cyanophytes and nanophytoplankton were the dominant classes. Relative bacteriochlorophyll-α concentrations varied around 2%. The transition zone between the Marquesas and the SPSG was also well predicted by the model. However, some regional characteristics have been observed where measured and modelled data differ. Amongst these features is the extreme depth of the DCM (180 m towards the centre of the gyre, the presence of a deep nanoflagellate population beneath the DCM or the presence of a prochlorophyte-enriched population in the formation area of the high salinity South Pacific Tropical Water. A coastal site sampled in the eutrophic upwelling zone, characterised by recently upwelled water, was significantly and unusually enriched in picoeucaryotes, in

  11. Extraction of antioxidant pigments from dye sorghum leaf sheaths

    NARCIS (Netherlands)

    Kayode, A.P.P.; Bara, C.A.; Dalode-Vieira, G.; Linnemann, A.R.; Nout, M.J.R.

    2012-01-01

    Extraction of antioxidant biocolorant pigments from leaf sheaths of dye sorghum was optimized. Effects of temperature and ethanol concentration of the extraction solvent on the concentrations of the 3-deoxyanthocyanidins, total phenolics and total anthocyanins, and the colour parameters of the

  12. Electrochemical assessing corrosion inhibiting effects of zinc aluminum polyphosphate (ZAPP) as a modified zinc phosphate pigment

    International Nuclear Information System (INIS)

    Naderi, R.; Attar, M.M.

    2008-01-01

    Undesirable anti-corrosion performance of zinc phosphate pigment, the classical chromate replacement, has led researchers to take modification into account. Polyphosphate-based anti-corrosion pigments as a result of modification of zinc orthophosphate have been found to function much more efficiently. This study aimed to evaluate performance of steel samples immersed in 3.5% NaCl aqueous solution-containing zinc aluminum polyphosphate (ZAPP) pigment extract compared to those involving conventional zinc phosphate (ZP) pigment extract and also no pigment (blank) using electrochemical tests such as electrochemical impedance spectroscopy (EIS) and linear polarization (LP) as well as surface analysis. Impedance spectra and polarization curves revealed two different trends, showing the superiority of ZAPP pigment. Based on the results of scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX), presence of a precipitated layer on the surface was confirmed when steel sample was immersed into the solution-containing ZAPP

  13. Water Fastness of Screen Printed Pearl Luster Pigments based on Synthetic and Natural Mica on Polyvinyl Chloride Foil and Rich Mineral Paper

    Directory of Open Access Journals (Sweden)

    Mirica Karlovits

    2013-01-01

    Full Text Available The present study attempts to examine water fastness of screen printed pearl luster pigments based on synthetic and natural mica on polyvinyl chloride foil and Rich Mineral Paper. Three types of pearl luster pigments were used, each different from the other in composition, interference colour and particle size: one pigment based on synthetic mica (Pigment 1 and two pigments based on natural mica (Pigment 2 and Pigment 3. Pearl luster pigments were applied to the printing base (PVC transparent base in 15wt.% concentration and printed by means of screen printing technique. The test of water fastness was made on prints, where the samples were soaked in distilled water for 6 and 12 days. It was established that this water treatment did not have any significant impact on the durability of screen printed pearl luster pigments. The pigments could demonstrate slightly better water fastness after being printed on Rich Mineral Paper.

  14. Model dependences of the deactivation of phytoplankton pigment excitation energy on environmental conditions in the sea

    Directory of Open Access Journals (Sweden)

    Mirosława Ostrowska

    2012-11-01

    Full Text Available A semi-empirical, physical models have been derived of the quantum yield ofthe deactivation processes (fluorescence, photosynthesis and heat productionof excited states in phytoplankton pigment molecules. Besides some alreadyknown models (photosynthesis and fluorescence, this novel approachincorporates the dependence of the dissipation yield of the excitation energyin phytoplankton pigment molecules on heat. The quantitative dependences ofthe quantum yields of these three processes on three fundamental parameters ofthe marine environment are defined: the chlorophyll concentration in the surface water layer Ca(0 (the basin trophicity,the irradiance PAR(z and the temperature temp(z at the study site.The model is complemented with two other relevant models describing thequantum yield of photosynthesis and of natural Sun-Induced Chlorophyll a Fluorescence (SICF in the sea, derived earlier by the author or with herparticipation on the basis of statistical analyses of a vast amount ofempirical material. The model described in the present paper enables theestimation of the quantum yields of phytoplankton pigment heat production forany region and season, in waters of any trophicity at different depths fromthe surface to depths of ca 60 m. The model can therefore be used to estimatethe yields of these deactivation processes in more than half the thickness ofthe euphotic zone in oligotrophic waters and in the whole thickness (anddeeper of this zone in mesotrophic and eutrophic waters. In particular theserelationships may be useful for a component analysis of the budget of lightenergy absorbed by phytoplankton pigments, namely, its utilization influorescence, photochemical quenching and nonphotochemical radiationlessdissipation - i.e. direct heat production.

  15. Producing the surface structures with required properties with the help of concentrated fluxes of particles

    International Nuclear Information System (INIS)

    Li, I.P.; Rukhlyada, N.Ya.

    2005-01-01

    Pulsed plasma treatment has been proposed for modification of the surface layers of metal-matrix-porous cathodes and parts of electronic-vacuum devices. Surface plasma treatment leads to improvement of thermal emission properties of effective cathodes: work function decreases, secondary electron emission coefficient increases, and surface emission uniformity improves. With the help of pulse plasma, surface smoothing as well as formation of composite coatings can be done [ru

  16. Irradiation induced surface segregation in concentrated alloys: a contribution; Contribution a l`etude de la segregation de surface induite par irradiation dans les alliages concentres

    Energy Technology Data Exchange (ETDEWEB)

    Grandjean, Y.

    1996-12-31

    A new computer modelization of irradiation induced surface segregation is presented together with some experimental determinations in binary and ternary alloys. The model we propose handles the alloy thermodynamics and kinetics at the same level of sophistication. Diffusion is described at the atomistic level and proceeds vis the jumps of point defects (vacancies, dumb-bell interstitials): the various jump frequencies depend on the local composition in a manner consistent with the thermodynamics of the alloy. For application to specific alloys, we have chosen the simplest statistical approximation: pair interactions in the Bragg Williams approximation. For a system which exhibits the thermodynamics and kinetics features of Ni-Cu alloys, the model generates the behaviour parameters (flux and temperature) and of alloy composition. Quantitative agreement with the published experimental results (two compositions, three temperatures) is obtained with a single set of parameters. Modelling austenitic steels used in nuclear industry requires taking into account the contribution of dumbbells to mass transport. The effects of this latter contribution are studied on a model of Ni-Fe. Interstitial trapping on dilute impurities is shown to delay or even suppress the irradiation induced segregation. Such an effect is indeed observed in the experiments we report on Fe{sub 50}Ni{sub 50} and Fe{sub 49}Ni{sub 50}Hf{sub 1} alloys. (author). 190 refs.

  17. The Effect of Different Fiber Concentrations on the Surface Roughness of Provisional Crown and Fixed Partial Denture Resin

    OpenAIRE

    Zortuk, Mustafa; K?l?c, Kerem; Uzun, Gulay; Ozturk, Ahmet; Kesim, Bulent

    2008-01-01

    Objectives The aim of this study was to investigate surface roughness in provisional crown acrylics, after polishing, reinforced with different concentrations of glass fibers. Methods A total of 48 disk-shaped specimens were prepared using autopolymerizing acrylic resin. These specimens were divided into four groups according to the level of glass fiber added: Group A (no fiber), Group B (0.5%), Group C (1%) and Group D (2%). After polishing the specimens, an average surface roughness (Ra) va...

  18. Tetrapyrrole pigments in the geologic record

    Energy Technology Data Exchange (ETDEWEB)

    Louda, J.W.; Baker, E.W.

    1985-01-01

    This paper is a synthesis of our ongoing studies on the fossilization of biotic tetrapyrrole pigments and is directed at revealing the utility of such study in assessing pre-, syn- and post-depositional processes. Diagenesis is found to become fated during oxic or anoxic deposition as to pigment destruction or fossilization, respectively. The progress of organic maturation has been followed in suited of oceanic sediments as well as shales and petroleum crudes from various basins in the US and Canada. Early catagenesis is witnessed by the release (ex kerogen.) of large quantities, re bitumen, of C28 to C34 V=O porphyrins. As catagenesis continues pigment concentration decreases, due to dilution, and higher C number porphyrins (C34-C45+) are added. Once the source is depleted or divorced from the bitumen, maturation leads to dealkylation which ends in the destruction of all tetrapyrrole structure. These changes are in concert with a shift from DPEP to ETIO dominance and parallel overall organic maturation in strict fashions. Organic source and paleoenvironment may also be addressed through porphyrin studies. Patterns of tetrapyrroles can differentiate the more allochthonous nature of black shale OM in the N. Atlantic from the autochthonous materials in these sequences in the margins of N.W. Africa and the S. Atlantic (high yield, DPEP).

  19. Exciton diffusion length and concentration of holes in MEH-PPV polymer using the surface voltage and surface photovoltage methods

    Czech Academy of Sciences Publication Activity Database

    Toušek, J.; Toušková, J.; Remeš, Zdeněk; Čermák, Jan; Kousal, J.; Kindl, Dobroslav; Kuřitka, I.

    2012-01-01

    Roč. 552, NOV (2012), s. 49-52 ISSN 0009-2614 R&D Projects: GA ČR(CZ) GBP108/12/G108 Institutional research plan: CEZ:AV0Z10100521 Keywords : surface photovoltage * Kelvin probe force microscopy * conjugated polymers Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.145, year: 2012

  20. The effect of sub-minimum inhibitory concentration of ciprofloxacin concentrations on enteroaggregative Escherichia coli and the role of the surface protein dispersin

    Energy Technology Data Exchange (ETDEWEB)

    Mortensen, Ninell P [ORNL; Fowlkes, Jason Davidson [ORNL; Trevino-Dopatka, Sonia [ORNL; Maggart, Michael J [ORNL; Boisen, Nadia [University of Virginia School of Medicine; Doktycz, Mitchel John [ORNL; Nataro, James [University of Virginia School of Medicine; Allison, David P [ORNL

    2011-01-01

    Enteroaggregative Escherichia coli (EAEC) are bacterial pathogens that cause watery diarrhea, which is often persistent and can be inflammatory. The antibiotic ciprofloxacin is used to treat EAEC infections, but a full understanding of the antimicrobial effects of ciprofloxacin is needed for more efficient treatment of bacterial infections. In this study, it was found that sub-minimum inhibitory concentrations (sub-MICs) of ciprofloxacin had an inhibitory effect on EAEC adhesion to glass and mammalian HEp-2 cells. It was also observed that bacterial surface properties play an important role in bacterial sensitivity to ciprofloxacin. In an EAEC mutant strain where the hydrophobic positively charged surface protein dispersin was absent, sensitivity to ciprofloxacin was reduced compared with the wild-type strain. Identified here are several antimicrobial effects of ciprofloxacin at sub-MIC concentrations indicating that bacterial surface hydrophobicity affects the response to ciprofloxacin. Investigating the effects of sub-MIC doses of antibiotics on targeted bacteria could help to further our understanding of bacterial pathogenicity and elucidate future antibiotic treatment modalities.

  1. Remote sensing of vertical phytoplankton pigment distributions in the Baltic: new mathematical expressions. Part 1: Total chlorophyll a distribution

    Directory of Open Access Journals (Sweden)

    Jerzy Dera

    2007-12-01

    Full Text Available This article is the first in a series of three describing the modelling of the vertical different photosynthetic and photoprotecting phytoplankton pigments concentration distributions in the Baltic and their interrelationsdescribed by the so-called non-photosynthetic pigment factor.The model formulas yielded by this research are an integral part of the algorithms used in the remote sensingof the Baltic ecosystem. Algorithms of this kind have already been developed by our team from data relating mainly to oceanic Case 1 waters (WC1 and have produced good results for these waters. But their application to Baltic waters, i.e.,Case 2 waters, was not so successful. On the basis of empirical data for the Baltic Sea, we therefore derived new mathematical expressions for the spatial distribution of Baltic phytoplankton pigments. They are discussed in this series of articles. This first article presents a statistical model for determining the total concentration ofchlorophyll, a (i.e., the sum of chlorophylls a+pheo derived spectrophotometrically at different depths in the Baltic Sea Ca(z on the basis of its surface concentration Ca(0,which can be determined by remote sensing. This model accounts for the principal features of the vertical distributions of chlorophyll concentrations characteristic of the Baltic Sea. The model's precision was verified empirically: it was found suitable for application in the efficient monitoring of the Baltic Sea. The modified mathematical descriptions of the concentrations of accessory pigments (photosynthetic and photoprotecting in Baltic phytoplankton and selected relationships between them are given in the other two articles in this series (Majchrowski et al. 2007, Woźniak et al. 2007b, both in this volume.

  2. False negative rate and other performance measures of a sponge-wipe surface sampling method for low contaminant concentrations.

    Energy Technology Data Exchange (ETDEWEB)

    Einfeld, Wayne; Krauter, Paula A.; Boucher, Raymond M.; Tezak, Mathew; Amidan, Brett G. (Pacific Northwest National Laboratory, Richland, WA); Piepel, Greg F. (Pacific Northwest National Laboratory, Richland, WA)

    2011-05-01

    Recovery of spores from environmental surfaces is known to vary due to sampling methodology, techniques, spore size and characteristics, surface materials, and environmental conditions. A series of tests were performed to evaluate a new, validated sponge-wipe method. Specific factors evaluated were the effects of contaminant concentrations and surface materials on recovery efficiency (RE), false negative rate (FNR), limit of detection (LOD) - and the uncertainties of these quantities. Ceramic tile and stainless steel had the highest mean RE values (48.9 and 48.1%, respectively). Faux leather, vinyl tile, and painted wood had mean RE values of 30.3, 25.6, and 25.5, respectively, while plastic had the lowest mean RE (9.8%). Results show a roughly linear dependence of surface roughness on RE, where the smoothest surfaces have the highest mean RE values. REs were not influenced by the low spore concentrations tested (3 x 10{sup -3} to 1.86 CFU/cm{sup 2}). The FNR data were consistent with RE data, showing a trend of smoother surfaces resulting in higher REs and lower FNRs. Stainless steel generally had the lowest mean FNR (0.123) and plastic had the highest mean FNR (0.479). The LOD{sub 90} varied with surface material, from 0.015 CFU/cm{sup 2} on stainless steel up to 0.039 on plastic. Selecting sampling locations on the basis of surface roughness and using roughness to interpret spore recovery data can improve sampling. Further, FNR values, calculated as a function of concentration and surface material, can be used pre-sampling to calculate the numbers of samples for statistical sampling plans with desired performance, and post-sampling to calculate the confidence in characterization and clearance decisions.

  3. Effect of concentration and pH on the surface-enhanced Raman scattering of captopril on nano-colloidal silver surface

    Science.gov (United States)

    Gao, Junxiang; Gu, Huaimin; Liu, Fangfang; Dong, Xiao; Xie, Min; Hu, Yongjun

    2011-07-01

    In this report, Raman and surface-enhanced Raman scattering (SERS) spectra of captopril are studied in detail. Herein, the Raman bands are assigned by the density functional theory (DFT) calculations and potential energy distributions (PED) based on internal coordinates of the molecule, which are found to be in good agree with the experimental values. Furthermore, the concentration and pH dependence of the SERS intensity of the molecule is discussed. By analyzing the intensities variation of SERS bands of the different concentrations of captopril solution, it can be concluded that the molecules orientation adsorbed on the silver nanoparticles surface change with the change of the concentrations. The variation of SERS spectra of captopril with the change of pH suggests that the interaction among the adsorbates with Ag cluster depend on the protonated state of the adsorbate and the aggregation of silver nanoparticles.

  4. Observational assessment of the role of nocturnal residual-layer chemistry in determining daytime surface particulate nitrate concentrations

    Directory of Open Access Journals (Sweden)

    G. Prabhakar

    2017-12-01

    Full Text Available This study discusses an analysis of combined airborne and ground observations of particulate nitrate (NO3−(p concentrations made during the wintertime DISCOVER-AQ (Deriving Information on Surface Conditions from COlumn and VERtically resolved observations relevant to Air Quality study at one of the most polluted cities in the United States – Fresno, CA – in the San Joaquin Valley (SJV and focuses on developing an understanding of the various processes that impact surface nitrate concentrations during pollution events. The results provide an explicit case-study illustration of how nighttime chemistry can influence daytime surface-level NO3−(p concentrations, complementing previous studies in the SJV. The observations exemplify the critical role that nocturnal chemical production of NO3−(p aloft in the residual layer (RL can play in determining daytime surface-level NO3−(p concentrations. Further, they indicate that nocturnal production of NO3−(p in the RL, along with daytime photochemical production, can contribute substantially to the buildup and sustaining of severe pollution episodes. The exceptionally shallow nocturnal boundary layer (NBL heights characteristic of wintertime pollution events in the SJV intensify the importance of nocturnal production aloft in the residual layer to daytime surface concentrations. The observations also demonstrate that dynamics within the RL can influence the early-morning vertical distribution of NO3−(p, despite low wintertime wind speeds. This overnight reshaping of the vertical distribution above the city plays an important role in determining the net impact of nocturnal chemical production on local and regional surface-level NO3−(p concentrations. Entrainment of clean free-tropospheric (FT air into the boundary layer in the afternoon is identified as an important process that reduces surface-level NO3−(p and limits buildup during pollution episodes. The influence of dry deposition of HNO

  5. Observational assessment of the role of nocturnal residual-layer chemistry in determining daytime surface particulate nitrate concentrations

    Science.gov (United States)

    Prabhakar, Gouri; Parworth, Caroline L.; Zhang, Xiaolu; Kim, Hwajin; Young, Dominique E.; Beyersdorf, Andreas J.; Ziemba, Luke D.; Nowak, John B.; Bertram, Timothy H.; Faloona, Ian C.; Zhang, Qi; Cappa, Christopher D.

    2017-12-01

    This study discusses an analysis of combined airborne and ground observations of particulate nitrate (NO3-(p)) concentrations made during the wintertime DISCOVER-AQ (Deriving Information on Surface Conditions from COlumn and VERtically resolved observations relevant to Air Quality) study at one of the most polluted cities in the United States - Fresno, CA - in the San Joaquin Valley (SJV) and focuses on developing an understanding of the various processes that impact surface nitrate concentrations during pollution events. The results provide an explicit case-study illustration of how nighttime chemistry can influence daytime surface-level NO3-(p) concentrations, complementing previous studies in the SJV. The observations exemplify the critical role that nocturnal chemical production of NO3-(p) aloft in the residual layer (RL) can play in determining daytime surface-level NO3-(p) concentrations. Further, they indicate that nocturnal production of NO3-(p) in the RL, along with daytime photochemical production, can contribute substantially to the buildup and sustaining of severe pollution episodes. The exceptionally shallow nocturnal boundary layer (NBL) heights characteristic of wintertime pollution events in the SJV intensify the importance of nocturnal production aloft in the residual layer to daytime surface concentrations. The observations also demonstrate that dynamics within the RL can influence the early-morning vertical distribution of NO3-(p), despite low wintertime wind speeds. This overnight reshaping of the vertical distribution above the city plays an important role in determining the net impact of nocturnal chemical production on local and regional surface-level NO3-(p) concentrations. Entrainment of clean free-tropospheric (FT) air into the boundary layer in the afternoon is identified as an important process that reduces surface-level NO3-(p) and limits buildup during pollution episodes. The influence of dry deposition of HNO3 gas to the surface on

  6. Pigment production from a mangrove Penicillium | Chintapenta ...

    African Journals Online (AJOL)

    A mangrove Penicillium producing red pigment was cultured in an optimized medium that was designed by the authors previously and used in this study. The purpose of this study was to identify the pigment and also to study the effect of bio elements on pigment production. Pigment from the medium was efficiently extracted ...

  7. Pigment production from a mangrove Penicillium

    African Journals Online (AJOL)

    SAM

    2014-06-25

    Jun 25, 2014 ... A mangrove Penicillium producing red pigment was cultured in an optimized medium that was designed by the authors previously and used in this study. The purpose of this study was to identify the pigment and also to study the effect of bio elements on pigment production. Pigment from the medium was.

  8. [Synthesis and characterization of mixed metal oxide pigments].

    Science.gov (United States)

    Ding, Jie; Yue, Shi-juan; Liu, Cui-ge; Wei, Yong-ju; Meng, Tao; Jiang, Han-jie; Shi, Yong-zheng; Xu, Yi-zhuang; Yu, Jiang; Wu, Jin-guang

    2012-03-01

    In the present work, aluminum chloride and various soluble salts of doping ions were dissolved in water. In addition, urea and polyvinyl pyrrolidone (PVP) were also dissolved in the above aqueous solution under supersonic treatments. Then the solutions were heated to induce the hydrolysis of urea so that soluble aluminum and doping ions convert into insoluble hydroxide or carbonate gels. After calcinations, the obtained gels change to mixed metal oxide pigments whose color is related to type and concentrations of the doping ions. XRD characterization demonstrates that the diffraction patterns of the products are the same as that of alpha-alumina. Diffuse reflectance spectra of samples of the samples in UV-Vis regions show that the absorption bands for d-d transitions of the doping ions undergo considerable change as the coordinate environments change. In addition, L*, a* and b* values of the pigments were measured by using UV-Vis densitometer. SEM results indicate that the size of the pigment powders is in the range 200-300 nm. The pigments are quite stable since no evidence of dissolution was observed after the synthesized pigment is soaked for 24 hours. ICP test shows that very little amount of doped metal occurs in the corresponding filtrate. The above results suggest that these new kinds of mixed metal oxide pigments are stable, non-toxic, environmental friendly and they may be applicable in molten spinning process and provide a new chance for non-aqueous printing and dyeing industry.

  9. Pigment dispersion syndrome associated with spontaneous subluxation of crystalline lens

    Directory of Open Access Journals (Sweden)

    Vikas Veerwal

    2017-01-01

    Full Text Available Pigment dispersion syndrome (PDS is an ocular condition characterized by a dispersion of iris pigment throughout the eye. This pigment is deposited in a characteristic manner on the corneal endothelium as Krukenberg's spindle, anterior surface of the iris, in the trabecular meshwork, on the lens and zonule and occasionally on the anterior hyaloid face. Even with deposition of pigment on zonular fibers, no zonular weakness, or zonular dehiscence has been reported in these cases. We report a unique case of PDS with bilateral spontaneous subluxation of crystalline lens. With characteristic findings of pigment distribution in both his eyes, the patient had concave iris configuration with heavily pigmented trabecular meshwork confirming the diagnosis of PDS. The patient had bilateral 180° temporal subluxation of crystalline lens in both his eyes. The usual cause of lens subluxation such as Marfan's Syndrome and Ehler's Danlos Syndrome was ruled out. The patient underwent right eye followed by left eye intracapsular cataract extraction with ab-interno technique with postoperative best-corrected visual acuity (BCVA of 6/9 in both eyes. Spontaneous subluxation of crystalline lens in isolated PDS is not known to occur and has been reported by means of this case. We recommend a thorough assessment of zonular status in all cases of PDS.

  10. Oral pigmentation induced by Premarin.

    Science.gov (United States)

    Pérusse, R; Morency, R

    1991-07-01

    Pigmented lesions of the oral cavity are important entities. The wide range of their clinical differential diagnosis includes such diverse systemic conditions as Addison's disease, Peutz-Jeghers syndrome, malignant melanoma, Kaposi's sarcoma, as well as specific oral lesions, such as amalgam tattoo or gingival melanosis. This paper reports a very rare cause of oral pigmentation, a melanic type, related to the use of Premarin.

  11. TASTRAK spectroscopy of polonium-210 alpha-particle activity at bone surfaces: Evidence for a concentrated surface deposit less than 3 μm deep

    International Nuclear Information System (INIS)

    Salmon, P.L.; Henshaw, D.L.; Keitch, P.A.; Allen, J.E.; Fews, A.P.

    1994-01-01

    The technique of α-particle spectroscopy by CR-39 type TASTRAK plastic has been used to study the depth distribution of natural α-particle emitters at the surface of human bone. The predominant component of this α-particle activity was 210 Po supported by 210 Pb, although a smaller activity of 226 Ra was also detected. Autopsy samples of human femur and cranium were obtained from subjects age 63 to 86. Both cortical and trabecular surfaces were analyzed. The results indicate that 210 Pb-supported 210 Po is concentrated at the surfaces of human bone from elderly subjects, in a narrow band 3 μm deep or less, by a factor of about four. As a result, the α-particle dose to the nuclei of cells lining bone surfaces is around 1.8 times greater than that calculated for a uniform volume distribution. Polonium-210 activity indicates the distribution of 210 Pb, and of stable lead, received by continuous intake throughout life at a very low level. A persistent bone surface concentration of lead and other osteotropic metals may be associated with the hypermineralized layer about 1 μm thick which occurs at the surface of resting bone mineral. 31 refs., 9 figs., 3 tabs

  12. (137)Cs concentrations in Atlantic and western Antarctic surface waters: results of the 7th Ukrainian Antarctic Expedition, 2002.

    Science.gov (United States)

    Gulin, S B; Stokozov, N A

    2005-01-01

    The latitudinal distribution of (137)Cs in the Atlantic--western Antarctic surface waters was studied during the 7th Ukrainian Antarctic Expedition in January--May 2002. The (137)Cs concentrations have also been measured in the upper ice of the coastal glacier Woozle Hill located near the Ukrainian Antarctic station "Akademik Vernadsky" (western Antarctica, 65 degrees 15' S-64 degrees 16' W). Comparison of these data with results of previous same-route expeditions SWEDARP (Swedish Antarctic Research Expedition, 1988/1989) and the French R/V "Jeanne d'Arc" (1992/1993), has shown practically parallel changes of (137)Cs surface concentrations between 40 degrees N and 20 degrees S, pointing to decrease of (137)Cs radioactivity at these latitudes with an apparent half-life of 10--15 years (12.5+/-2.1 years on average). This suggests that decrease of (137)Cs surface concentration within this latitude band is controlled, besides the radioactive decay of (137)Cs (half-life=30 years), by vertical mixing of the upper water masses. South of 20 degrees S, the (137)Cs concentrations in surface water have decreased more rapidly because of the influence of the less contaminated Antarctic waters. At 50--60 degrees S and near the Antarctic coast, the (137)Cs activity in 2002 was similar to those measured during the SWEDARP and "Jeanne d'Arc" expeditions, suggesting an additional input of (137)Cs to these waters from the melted ice from the adjacent glaciers.

  13. Investigation Into Accessible Surface Vinyl Concentrations of Nonstoichiometric PDMS Microspheres from Hydrosilylation Reactions and Their Further Crosslinking Reactions

    DEFF Research Database (Denmark)

    Ma, Baoguang; Hansen, Jens Henrik; Hvilsted, Søren

    2015-01-01

    titration method, which is based on efficiently and covalently bonding mono-functional hydride to vinyl, is employed to determine surface vinyl concentration. The titration method exhibits good reproducibility in detection, thereby underlining its potential applicability as a general titration method...

  14. Estimating daily surface NO2 concentrations from satellite data - a case study over Hong Kong using land use regression models

    Science.gov (United States)

    Anand, Jasdeep S.; Monks, Paul S.

    2017-07-01

    Land use regression (LUR) models have been used in epidemiology to determine the fine-scale spatial variation in air pollutants such as nitrogen dioxide (NO2) in cities and larger regions. However, they are often limited in their temporal resolution, which may potentially be rectified by employing the synoptic coverage provided by satellite measurements. In this work a mixed-effects LUR model is developed to model daily surface NO2 concentrations over the Hong Kong SAR during the period 2005-2015. In situ measurements from the Hong Kong Air Quality Monitoring Network, along with tropospheric vertical column density (VCD) data from the OMI, GOME-2A, and SCIAMACHY satellite instruments were combined with fine-scale land use parameters to provide the spatiotemporal information necessary to predict daily surface concentrations. Cross-validation with the in situ data shows that the mixed-effects LUR model using OMI data has a high predictive power (adj. R2 = 0. 84), especially when compared with surface concentrations derived using the MACC-II reanalysis model dataset (adj. R2 = 0. 11). Time series analysis shows no statistically significant trend in NO2 concentrations during 2005-2015, despite a reported decline in NOx emissions. This study demonstrates the utility in combining satellite data with LUR models to derive daily maps of ambient surface NO2 for use in exposure studies.

  15. Determination of surface concentrations of individual molecule-layers used in nanoscale biosensors by in situ ATR-FTIR spectroscopy

    KAUST Repository

    Punzet, Manuel

    2012-01-01

    For the development of nanowire sensors for chemical and medical detection purposes, the optimal functionalization of the surface is a mandatory component. Quantitative ATR-FTIR spectroscopy was used in situ to investigate the step-by-step layer formation of typical functionalization protocols and to determine the respective molecule surface concentrations. BSA, anti-TNF-α and anti-PSA antibodies were bound via 3-(trimethoxy)butylsilyl aldehyde linkers to silicon-oxide surfaces in order to investigate surface functionalization of nanowires. Maximum determined surface concentrations were 7.17 × 10 -13 mol cm -2 for BSA, 1.7 × 10 -13 mol cm -2 for anti-TNF-α antibody, 6.1 × 10 -13 mol cm -2 for anti-PSA antibody, 3.88 × 10 -13 mol cm -2 for TNF-α and 7.0 × 10 -13 mol cm -2 for PSA. Furthermore we performed antibody-antigen binding experiments and determined the specific binding ratios. The maximum possible ratio of 2 was obtained at bulk concentrations of the antigen in the μg ml -1 range for TNF-α and PSA. © 2012 The Royal Society of Chemistry.

  16. Yolk pigments of the Mexican leaf frog.

    Science.gov (United States)

    Marinetti, G V; Bagnara, J T

    1983-02-25

    Eggs of the Mexican leaf frog contain blue and yellow pigments identified as biliverdin and lutein, respectively. Both pigments are bound to proteins that occur in crystalline form in the yolk platelet. The major blue pigment is biliverdin IX alpha. The eggs vary in color from brilliant blue to pale yellow-green depending on the amount of each pigment. These pigments may provide protective coloration to the eggs.

  17. CONCENTRATION DEPENDENCE OF STERN LAYER CAPACITANCES AND SURFACE EQUILIBRIUM CONSTANTS IN SILICA-BASED NANOFLUIDIC CHANNELS

    DEFF Research Database (Denmark)

    Andersen, Mathias Bækbo; Frey, J.; Bruus, Henrik

    2010-01-01

    ]. The current models used to describe surface phenomena in nanofluidics can differ by orders of magnitude from experimentally measured values [2]. To mitigate the discrepancies, we hypothesize that the Stern-layer capacitance Cs and the surface equilibrium constants pKa, vary with the composition of the solid...

  18. Spatial and temporal analysis of pesticides concentrations in surface water: Pesticides atlas

    NARCIS (Netherlands)

    Vijver, M.G.; Zelfde, van 't M.; Tamis, W.L.M.; Snoo, de G.R.

    2008-01-01

    Dutch water boards have a well-established program for monitoring pesticide contamination of surface waters. These monitoring data have been processed into a graphic format accessible online and designed to provide insight into pesticide presence in Dutch surface waters and trends over time: the

  19. Prediction of sub-surface 37 Ar concentrations at locations in the Northwestern United States

    Energy Technology Data Exchange (ETDEWEB)

    Fritz, Bradley G.; Aalseth, Craig E.; Back, Henning O.; Hayes, James C.; Humble, Paul H.; Ivanusa, Pavlo; Mace, Emily K.

    2018-01-01

    The Comprehensive Nuclear Test-Ban Treaty, which is intended to prevent nuclear weapon testing, includes a verification regime, which provides monitoring to identify potential nuclear testing. The presence of elevated 37Ar is one way to identify subsurface nuclear testing. However, the naturally occurring formation of 37Ar in the subsurface adds a complicating factor. Prediction of the naturally occurring concentration of 37Ar can help to determine if a measured 37Ar concentration is elevated. The naturally occurring 37Ar background concentration has been shown to vary between less than 1 mBq/m3 to greater than 100 mBq/m3 (Riedmann and Purtschert 2011). Here, we evaluate a model for predicting the average concentration of 37Ar at any depth under transient barometric pressures, and compare it with measurements. This model is shown to compare favorably with concentrations of 37Ar measured at multiple locations in the Northwestern United States.

  20. Heterogeneity of soil surface ammonium concentration and other characteristics, related to plant specific variability in a Mediterranean-type ecosystem

    International Nuclear Information System (INIS)

    Cruz, Cristina; Bio, Ana M.F.; Jullioti, Aldo; Tavares, Alice; Dias, Teresa; Martins-Loucao, Maria Amelia

    2008-01-01

    Heterogeneity and dynamics of eight soil surface characteristics essential for plants-ammonium and nitrate concentrations, water content, temperature, pH, organic matter, nitrification and ammonification rates-were studied in a Mediterranean-type ecosystem on four occasions over a year. Soil properties varied seasonally and were influenced by plant species. Nitrate and ammonium were present in the soil at similar concentrations throughout the year. The positive correlation between them at the time of greatest plant development indicates that ammonium is a readily available nitrogen source in Mediterranean-type ecosystems. The results presented here suggest that plant cover significantly affects soil surface characteristics. - In Mediterranean-type ecosystems ammonium is present in the soil throughout the year and its concentration is dependent on plant cover

  1. Protocol optimization for enhanced production of pigments in Spirulina.

    Science.gov (United States)

    Kumar, Devendra; Kumar, Neeraj; Pabbi, Sunil; Walia, Suresh; Dhar, Dolly Wattal

    2013-01-01

    Spirulina has attracted special attention due to its importance as human foodstuff and natural colours with specific functional properties. These functional properties have been attributed to phycobilins, carotenoids, phenolics and unsaturated fatty acids. Present study was conducted under controlled phytotron conditions to identify the efficient strains of Spirulina in terms of pigment synthesis and to optimize their enhanced production. Methodology for enhanced production was standardized by varying specific environmental parameters (light intensity, temperature, carbon dioxide concentration, pH and NaCl level). Different strains of Spirulina depicted variability and environmental parameters showed distinct influence on pigments. Growth and pigment production was recorded to be most efficient under optimized conditions of light intensity (70 μmol m -2  s -1 ), temperature (30 °C), CO 2 concentration (550 ppm and 750 ppm), pH (10.5) and NaCl level (2 g L -1 ).

  2. An ESR study of the spectra of paint pigments in 'drying' linseed oil

    International Nuclear Information System (INIS)

    Slogett, R.; Troup, G.; Hutton, D.

    1999-01-01

    Full text: Since previous ESR work on the identification of RAW paint pigments, mainly mineral, looked promising, we decided to examine the spectra when the pigments were applied, in oil, to a non-reactive, microwave transparent polymer. The polymer used shows no significant ESR signals in the range 2000-4000 gauss at ∼9.1 GHz and room temperature. The oil used is Winsor and Newton Drying Linseed Oil, and contains 'manganese driers'. The spectrum of the pure liquid oil is shown, as well as that of the dried oil on the substrate. Many of the pigment spectra shown are so strong that not a trace of the oil Mn(2+) can be seen at the pigment concentrations used. The effect of the linseed oil on modern synthetic indigo, an organic pigment still available made from plants, is also shown. ESR still looks to be a useful supplementary technique for paint pigment identification

  3. Fungal pigments inhibit the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis of darkly pigmented fungi.

    Science.gov (United States)

    Buskirk, Amanda D; Hettick, Justin M; Chipinda, Itai; Law, Brandon F; Siegel, Paul D; Slaven, James E; Green, Brett J; Beezhold, Donald H

    2011-04-01

    Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been used to discriminate moniliaceous fungal species; however, darkly pigmented fungi yield poor fingerprint mass spectra that contain few peaks of low relative abundance. In this study, the effect of dark fungal pigments on the observed MALDI mass spectra was investigated. Peptide and protein samples containing varying concentrations of synthetic melanin or fungal pigments extracted from Aspergillus niger were analyzed by MALDI-TOF and MALDI-qTOF (quadrupole TOF) MS. Signal suppression was observed in samples containing greater than 250ng/μl pigment. Microscopic examination of the MALDI sample deposit was usually heterogeneous, with regions of high pigment concentration appearing as black. Acquisition of MALDI mass spectra from these darkly pigmented regions of the sample deposit yielded poor or no [M+H](+) ion signal. In contrast, nonpigmented regions within the sample deposit and hyphal negative control extracts of A. niger were not inhibited. This study demonstrated that dark fungal pigments inhibited the desorption/ionization process during MALDI-MS; however, these fungi may be successfully analyzed by MALDI-TOF MS when culture methods that suppress pigment expression are used. The addition of tricyclazole to the fungal growth media blocks fungal melanin synthesis and results in less melanized fungi that may be analyzed by MALDI-TOF MS. Published by Elsevier Inc.

  4. Modeling uranium(VI) adsorption onto montmorillonite under varying carbonate concentrations: A surface complexation model accounting for the spillover effect on surface potential

    Science.gov (United States)

    Tournassat, C.; Tinnacher, R. M.; Grangeon, S.; Davis, J. A.

    2018-01-01

    The prediction of U(VI) adsorption onto montmorillonite clay is confounded by the complexities of: (1) the montmorillonite structure in terms of adsorption sites on basal and edge surfaces, and the complex interactions between the electrical double layers at these surfaces, and (2) U(VI) solution speciation, which can include cationic, anionic and neutral species. Previous U(VI)-montmorillonite adsorption and modeling studies have typically expanded classical surface complexation modeling approaches, initially developed for simple oxides, to include both cation exchange and surface complexation reactions. However, previous models have not taken into account the unique characteristics of electrostatic surface potentials that occur at montmorillonite edge sites, where the electrostatic surface potential of basal plane cation exchange sites influences the surface potential of neighboring edge sites ('spillover' effect). A series of U(VI) - Na-montmorillonite batch adsorption experiments was conducted as a function of pH, with variable U(VI), Ca, and dissolved carbonate concentrations. Based on the experimental data, a new type of surface complexation model (SCM) was developed for montmorillonite, that specifically accounts for the spillover effect using the edge surface speciation model by Tournassat et al. (2016a). The SCM allows for a prediction of U(VI) adsorption under varying chemical conditions with a minimum number of fitting parameters, not only for our own experimental results, but also for a number of published data sets. The model agreed well with many of these datasets without introducing a second site type or including the formation of ternary U(VI)-carbonato surface complexes. The model predictions were greatly impacted by utilizing analytical measurements of dissolved inorganic carbon (DIC) concentrations in individual sample solutions rather than assuming solution equilibration with a specific partial pressure of CO2, even when the gas phase was

  5. Surface Water Qualit: Revisiting Nitrate Concentrations in the Des Moines River: 1945 and 1976-2001

    Science.gov (United States)

    McIsaac, G.F.; Libra, R.D.

    2003-01-01

    Recent compilations of historical and contemporary riverine nitrate (NO3) concentrations indicate that concentrations in many rivers in the north-central USA increased during the second half of the 20th century. The Des Moines River near Des Moines, Iowa, however, was reported to have had similar NO3 concentrations in 1945 and the 1980s, in spite of substantially greater N input to the watershed during the latter period. The objective of this study was to reconsider the comparison of historical and contemporary NO3 concentrations in the Des Moines River near Des Moines in light of the following: (i) possible errors in the historical data used, (ii) variations in methods of sample collection, (iii) variations in location of sampling, and (iv) additional data collected since 1990. We discovered that an earlier study had compared the flow-weighted average concentration in 1945 to arithmetic annual average concentrations in the 1980s. The intertemporal comparison also appeared to be influenced by differences in sample collection methods and locations used at different times. Depending on the model used and the estimated effects of composite sample collection, the 1945 arithmetic average NO3 concentration was between 44 and 57% of the expected mean value at a similar water yield during 1976-2001. The flow-weighted average NO3 concentration for 1945 was between 54 and 73% of the expected mean value at a similar water yield during 1976-2001. The difference between NO3 concentrations in 1945 and the contemporary period are larger than previously reported for the Des Moines River.

  6. Bioactive compounds in pigmented rice bran inhibit growth of human cancer cells

    Science.gov (United States)

    Rice bran contains both lipophilic and hydrophilic antioxidants. Our previous studies have shown that pigmented rice cultivars contained several-fold higher total phenolic concentrations and antioxidant capacities than non-pigmented cultivars. We investigated three rice brans (purple, red and light-...

  7. Scytonemin and Photosynthetic Pigment Proxies for Late Pleistocene/Holocene Environmental Change in the Eastern Great Basin

    Science.gov (United States)

    Fulton, J. M.; Van Mooy, B. A. S.

    2015-12-01

    Sedimentary pigments are biomarkers of photosynthetic organisms, most commonly derived from aquatic bacteria and algae but also with potential terrigenous sources. We detected a diverse pigment assemblage with variable down-core distributions in Great Salt Lake (GSL) sediments deposited since ca. 280 ka (GLAD1-GSL00, core 4). The most abundant pigments included derivatives of chlorophyll a, most likely from algae or cyanobacteria, bacteriochlorophyll c from green sulfur bacteria, okenone from purple sulfur bacteria, and scytonemin from UV-exposed cyanobacteria. Scytonemin is a biomarker for colonial cyanobacteria exposed to UV-radiation. In GSL it has potential sources from bioherms on the shoreline or microbiotic soil crusts from the adjacent Great Basin Desert. Scytonemin concentration was highest in the Upper Salt and Sapropel (USS) unit, deposited between 11.5-10 ka in shallow water (ca. 10 m), following deep pluvial Lake Bonneville (30-18 cal ka), the Provo lake level (ca. 18-15 cal ka), and the Gilbert transgression (11.6 cal ka). Scytonemin concentration was very low in sediments deposited during the deep lake phases, even though bioherms were prominent shoreline features. The USS was deposited under hypersaline waters and contained remarkably low concentrations of photosynthetic pigment derivatives that would be expected in organic-matter-rich sediments deposited under productive surface waters or anoxic bottom waters. Stable carbon and nitrogen isotopic data point toward a desert soil crust source for scytonemin in the USS, similar to what we previously observed in the Holocene Black Sea sapropel. We propose that increased aridity supported the widespread occurrence and erosion of microbiotic soil crusts during deposition of the USS. This is consistent with interpretations of Great Salt Lake hydrology, pointing toward a broader regional aridity event. Holocene sediments above the USS also contain scytonemin at relatively high concentration, consistent with

  8. Elemental concentrations of aquatic insect larvae and attached algae on tone surfaces in an uncontaminated stream

    International Nuclear Information System (INIS)

    Momoshima, N.; Sugihara, S.; Hibino, K.; Nakamura, Y.

    2009-01-01

    Elemental concentrations of aquatic insect larvae and attached algae in an uncontaminated river were analyzed by instrumental neutron activation analysis (INAA) via the k 0 -standardization method. The aquatic insect larvae found were all intolerant species. No significant difference was observed int he elemental concentrations of aquatic insect larvae and attached algae long the river. Similar elemental concentrations were observed in the aquatic insect larvae collected at a fixed sampling point for two years. An analysis by the ratio-matching technique indicated a higher generic relationship between aquatic insect larvae and attached algae than river water. (author)

  9. Concentration Levels and Ecological Risks of Persistent Organic Pollutants in the Surface Sediments of Tianjin Coastal Area, China

    Directory of Open Access Journals (Sweden)

    Xiaoxia Lu

    2013-01-01

    Full Text Available Sediments were sampled from different surface water bodies in Tianjin coastal area, China, and persistent organic pollutants (POPs including polycyclic aromatic hydrocarbons (PAHs, organochlorine pesticides (OCPs, polychlorinated biphenyls (PCBs, and polybrominated diphenyl ethers (PBDEs were measured using GC/MS or GC/ECD. The purposes were to investigate the concentration levels of the POPs and to assess their ecological risks. The results showed that all the 16 priority PAHs were detected from the 10 sediments sampled with the total concentrations of the 16 PAHs ranging from 274.06 μg/kg to 2656.65 μg/kg, while the concentrations of the halogenated POPs were generally low except in the Dagu waste discharging river where the total concentrations of 24 OCPs, 35 PCBs, and 14 PBDEs were 3103.36 μg/kg, 87.31 μg/kg, and 13.88 μg/kg, respectively. In the studied sediments, PAHs exhibited risks to benthonic organisms; particularly the concentrations of naphthalene and/or acenaphthene exceeded their probable effect concentrations in several locations. In comparison, only in the Dagu waste discharging river, OCPs exhibited risks with the concentrations of heptachlor epoxide and lindane exceeding their probable effect concentrations. PCBs and PBDEs posed rare risks in the studied area.

  10. Effects of Ce concentrations on ignition temperature and surface tension of Mg-9wt.%Al alloy

    Directory of Open Access Journals (Sweden)

    Deng Zhenghua

    2013-03-01

    Full Text Available Magnesium alloys are well known for their excellent properties, but the potential issues with oxidation and burning during melting and casting largely limit its industrial applications. The addition of Ce in magnesium alloys can significantly raise ignition-proof performance and change the structure of the oxide film on the surface of the molten metal as well as the surface tension values. Surface tension is an important physical parameter of the metal melts, and it plays an important role in the formation of surface oxide film. In this present work, the ignition temperature and the surface tension of Mg-9wt.%Al alloy with different Ce concentrations were studied. Surface tensions was measured using the maximum bubble pressure method (MBPM. Ignition temperature was measured using NiCr-NiSi type thermocouples and was monitored and recorded via a WXT-604 desk recording device. The results show that the ignition point of Mg-9wt.%Al alloy can be effectively elevated by adding Ce. The ignition temperature reaches its highest point of 720 ℃ when the addition of Ce is 1wt.%. The surface tension of the molten Mg-9wt.%Al alloy decreases exponentially with the increase of Ce addition at the same temperature. Similarly, the experiment also shows that the surface tension of Mg-9wt.%Al alloy decreases exponentially with the increase of temperature.

  11. Effect of newly developed pigments and ultraviolet absorbers on the color change of pigmented silicone elastomer

    Directory of Open Access Journals (Sweden)

    Mohit G Kheur

    2017-01-01

    Conclusion: The newly developed pigment led to increased color stability as compared to commercially available pigments. Addition of UV stabilizer, Chimassorb led to a further reduction in color change of the pigmented elastomer.

  12. Differential sensitivity of pigmented and non-pigmented marine bacteria to metals and antibiotics

    Digital Repository Service at National Institute of Oceanography (India)

    Nair, S.; Chandramohan, D.; LokaBharathi, P.A.

    The response of pigmented and non-pigmented marine bacteria to metals and antibiotics was investigated. The two groups responded differently to heavy metals and antibiotics. Pigmented bacteria were more resistant to metals. Among the metals, Zn...

  13. Study of the processes of adsorption of amine-containing surface-active substance on the surface of Aluminum powder

    Directory of Open Access Journals (Sweden)

    Antonina Dyuryagina

    2012-03-01

    Full Text Available Equilibrium characteristics of adsorption on a surface of a pigment depending on concentration factors and temperature of the dispersive environment are defined. Kinetic laws of superficial activity of binary, threefold homogeneous and heterogeneous modeling systems are studied. The estimation of mechanisms of process of adsorption is carried out.

  14. Source tracking swine fecal waste in surface water proximal to swine concentrated animal feeding operations

    OpenAIRE

    Heaney, Christopher D.; Myers, Kevin; Wing, Steve; Hall, Devon; Baron, Dothula; Stewart, Jill R.

    2015-01-01

    Swine farming has gone through many changes in the last few decades, resulting in operations with a high animal density known as confined animal feeding operations (CAFOs). These operations produce a large quantity of fecal waste whose environmental impacts are not well understood. The purpose of this study was to investigate microbial water quality in surface waters proximal to swine CAFOs including microbial source tracking of fecal microbes specific to swine. For one year, surface water sa...

  15. Friction wear cast iron casting surface hardened by concentrated source of heat

    Directory of Open Access Journals (Sweden)

    W. Orlowicz

    2009-04-01

    Full Text Available In this study surface fusion by the GTAW (in argon atmosphere surfacing process on plate of cast iron with electric arc advance speedsfrom 200 to 800 mm/min and current range I=300A were performed. The geometry, microstructure, hardness, friction wear intensity weremeasured. A stepwise regression method was used to develop relationships between the electric arc advance speed, parameters of fusion geometry, microhardness and friction wear intensity.

  16. The Influence of Electrolytic Concentration on the Electrochemical Deposition of Calcium Phosphate Coating on a Direct Laser Metal Forming Surface

    Directory of Open Access Journals (Sweden)

    Qianyue Sun

    2017-01-01

    Full Text Available A calcium phosphate (CaP coating on titanium surface enhances its biocompatibility, thus facilitating osteoconduction and osteoinduction with the inorganic phase of the human bone. Electrochemical deposition has been suggested as an effective means of fabricating CaP coatings on porous surface. The purpose of this study was to develop CaP coatings on a direct laser metal forming implant using electrochemical deposition and to investigate the effect of electrolytic concentration on the coating’s morphology and structure by X-ray diffraction, scanning electron microscopy, water contact angle analysis, and Fourier transform infrared spectroscopy. In group 10−2, coatings were rich in dicalcium phosphate, characterized to be thick, layered, and disordered plates. In contrast, in groups 10−3 and 10−4, the relatively thin and well-ordered coatings predominantly consisted of granular hydroxyapatite. Further, the hydrophilicity and cell affinity were improved as electrolytic concentration increased. In particular, the cells cultured in group 10−3 appeared to have spindle morphology with thick pseudopodia on CaP coatings; these spindles and pseudopodia strongly adhered to the rough and porous surface. By analyzing and evaluating the surface properties, we provided further knowledge on the electrolytic concentration effect, which will be critical for improving CaP coated Ti implants in the future.

  17. Arsenic Concentration in the Surface Water of a Former Mining Area: The La Junta Creek, Baja California Sur, Mexico

    Science.gov (United States)

    Imaz Lamadrid, Miguel; Acosta Vargas, Baudilio

    2018-01-01

    The mining activity in the San Antonio-El Triunfo district, located in a mountainous region at 60 km southeast of La Paz, occured for more than 250 years and left behind severe contamination of soils and riverbed sediments which led to elevated concentrations of arsenic and other trace elements in the surface- and groundwater of the region. Although the main mining activity ended around 1911, contamination is still beeing distributed, especially from left behind tailings and mine waste piles. The contamination levels in the groundwater have been reported in several studies, but there is little information available on the surface water quality, and especially the temporal variation. In this study, we analyzed the surface water of the La Junta creek, in the southern part of the San Antonio-El Triunfo mining district. The working hypothesis was that by means of a spatial analysis of surface water and shallow groundwater, in combination with the temporal observation of the concentrations in runoff water, the effects of different sources of arsenic (natural geogene anomalies, due to historic mining activity, and hydrothermal related impact) in the La Junta creek can be recognized. This present study revealed that historic mining activity caused a mojor impact of arsenic but less contamination was observed than in the northern part of the district and elevated arsenic concentrations in stream water generally occurred during times of low streamflow. PMID:29498700

  18. Explaining global surface aerosol number concentrations in terms of primary emissions and particle formation

    Directory of Open Access Journals (Sweden)

    D. V. Spracklen

    2010-05-01

    Full Text Available We synthesised observations of total particle number (CN concentration from 36 sites around the world. We found that annual mean CN concentrations are typically 300–2000 cm−3 in the marine boundary layer and free troposphere (FT and 1000–10 000 cm−3 in the continental boundary layer (BL. Many sites exhibit pronounced seasonality with summer time concentrations a factor of 2–10 greater than wintertime concentrations. We used these CN observations to evaluate primary and secondary sources of particle number in a global aerosol microphysics model. We found that emissions of primary particles can reasonably reproduce the spatial pattern of observed CN concentration (R2=0.46 but fail to explain the observed seasonal cycle (R2=0.1. The modeled CN concentration in the FT was biased low (normalised mean bias, NMB=−88% unless a secondary source of particles was included, for example from binary homogeneous nucleation of sulfuric acid and water (NMB=−25%. Simulated CN concentrations in the continental BL were also biased low (NMB=−74% unless the number emission of anthropogenic primary particles was increased or a mechanism that results in particle formation in the BL was included. We ran a number of simulations where we included an empirical BL nucleation mechanism either using the activation-type mechanism (nucleation rate, J, proportional to gas-phase sulfuric acid concentration to the power one or kinetic-type mechanism (J proportional to sulfuric acid to the power two with a range of nucleation coefficients. We found that the seasonal CN cycle observed at continental BL sites was better simulated by BL particle formation (R2=0.3 than by increasing the number emission from primary anthropogenic sources (R2=0.18. The nucleation constants that resulted in best overall match between model and observed CN concentrations were

  19. Short-term temperature-dependent air-surface exchange and atmospheric concentrations of polychlorinated naphthalenes and organochlorine pesticides

    Energy Technology Data Exchange (ETDEWEB)

    Lee, R.G.M.; Burnett, V.; Harner, T.; Jones, K.C.

    2000-02-01

    Atmospheric concentrations of five organochlorine (OC) pesticides, some of which have been banned for a number of years, and polychlorinated naphthalenes (PCNs) were measured at a U.K. site over periods of 6 h for 7 days resulting in 28 samples. Mean concentrations of the pesticides were {alpha}-HCH 90 pg m{sup {minus}3}, {gamma}-HCH 500, {rho},{rho}{prime}-DDE 8, dieldrin 63, endrin 22, and HCB 39. PCN mean homologue concentrations were {sub 3}CNs 67 pg m{sup {minus}3}, {sub 4}CNs 78, {sub 5}CNs 5, {sub 6}CNs 0.6, {sub 7}CNs 0.6, and {Sigma}PCNs 152. TEQ concentrations for those PCNs ascribed TEF values ranged between 0.36 and 3.6 fg m{sup {minus}3} which corresponds to {approximately}3.0--30% of the TEQ concentrations of PCDD/Fs at the same site. All the compounds measured, except HCB, exhibited a strong temperature-dependent diurnal cycling. Results from Clausius-Clapeyron plots show that pesticide concentrations were controlled by temperature-driven air-surface recycling throughout the first 5 days when stable atmospheric conditions were dominant, while during the last 2 days advection became more influential as more unstable and cooler weather started to influence the site. PCN concentrations were controlled primarily by a mixture of recycling and advection throughout the first 5 days and then by advection in the final 2 days, suggesting that there are ongoing emissions from diffuse point sources of PCNs into the U.K. atmosphere. This study provides further evidence of the rapid air-surface exchange of semivolatile organic compounds (SOCs) and shows how different factors alone or in combination can produce rapid changes in the atmospheric concentrations of past and present SOCs.

  20. Diversity and functional properties of bistable pigments.

    Science.gov (United States)

    Tsukamoto, Hisao; Terakita, Akihisa

    2010-11-01

    Rhodopsin and related opsin-based pigments, which are photosensitive membrane proteins, have been extensively studied using a wide variety of techniques, with rhodopsin being the most understood G protein-coupled receptor (GPCR). Animals use various opsin-based pigments for vision and a wide variety of non-visual functions. Many functionally varied pigments are roughly divided into two kinds, based on their photoreaction: bistable and monostable pigments. Bistable pigments are thermally stable before and after photo-activation, but monostable pigments are stable only before activation. Here, we review the diversity of bistable pigments and their molecular characteristics. We also discuss the mechanisms underlying different molecular characteristics of bistable and monostable pigments. In addition, the potential of bistable pigments as a GPCR model is proposed.

  1. Utilization of surface Plasmon resonance band of silver nanoparticles for determination of critical micelle concentration of cationic surfactants

    Science.gov (United States)

    Salem, Jamil K.; El-Nahhal, Issa M.; Najri, Bassam A.; Hammad, Talaat M.

    2016-11-01

    We have utilized surface Plasmon resonance (SPR) band sensitivity to surfactant concentration to investigate the critical micelle concentration (cmc) of CTAB, HY and CPB. The process is based upon an in situ formation of silver nanoparticles (AgNPs) through the reduction of silver ions (Ag+) by diethylene triamine (DETA) at 25 °C. In the presence of cationic surfactants, Ag+ ions can be reduced to AgNPs in a few minutes, accompanied by changes in intensity and wavelength of the SPR band. The spectral shifts of SPR band and the change of color have been used to determine CMC values of cationic surfactants.

  2. Pigment signatures of phytoplankton composition in the northern ...

    African Journals Online (AJOL)

    Pigment indices were used to investigate the distribution and composition of phytoplankton in the northern Benguela during the austral spring of 2000, with sampling being conducted on five transect lines between 19°S and 25°S and at other inshore stations on the shelf. Total chlorophyll a concentrations (TChla) at the ...

  3. Apollo 12 lunar material - Effects on plant pigments.

    Science.gov (United States)

    Weete, J. D.; Walkinshaw, C. H.

    1972-01-01

    Tissue cultures of tobacco grown for 12 weeks in contact with lunar material returned by Apollo 12 contained 21 to 35% more total pigment than control tissues. This difference is due primarily to increased chlorophyll a concentrations per gram fresh weight of tissue in experimental cultures. No differences were noted in the fresh or dry weight of the experimental and control cultures.

  4. CONCENTRATION DEPENDENCE OF STERN LAYER CAPACITANCES AND SURFACE EQUILIBRIUM CONSTANTS IN SILICA-BASED NANOFLUIDIC CHANNELS

    DEFF Research Database (Denmark)

    Andersen, Mathias Bækbo; Frey, J.; Bruus, Henrik

    2010-01-01

    Fundamental understanding of the unique physics at the solid-liquid interface in nanofluidic channels is essential for the advancement of basic scientific knowledge and the development of novel applications for pharmaceuticals, environmental health and safety, energy harvesting and biometrics [1......]. The current models used to describe surface phenomena in nanofluidics can differ by orders of magnitude from experimentally measured values [2]. To mitigate the discrepancies, we hypothesize that the Stern-layer capacitance Cs and the surface equilibrium constants pKa, vary with the composition of the solid...

  5. Perstraction of Intracellular Pigments through Submerged Fermentation of Talaromyces spp. in a Surfactant Rich Media: A Novel Approach for Enhanced Pigment Recovery

    Directory of Open Access Journals (Sweden)

    Lourdes Morales-Oyervides

    2017-06-01

    Full Text Available A high percentage of the pigments produced by Talaromyces spp. remains inside the cell, which could lead to a high product concentration inhibition. To overcome this issue an extractive fermentation process, perstraction, was suggested, which involves the extraction of the intracellular products out of the cell by using a two-phase system during the fermentation. The present work studied the effect of various surfactants on secretion of intracellular pigments produced by Talaromyces spp. in submerged fermentation. Surfactants used were: non-ionic surfactants (Tween 80, Span 20 and Triton X-100 and a polyethylene glycerol polymer 8000, at different concentrations (5, 20, 35 g/L. The highest extracellular pigment yield (16 OD500nm was reached using Triton X-100 (35 g/L, which was 44% higher than the control (no surfactant added. The effect of addition time of the selected surfactant was further studied. The highest extracellular pigment concentration (22 OD500nm was achieved when the surfactant was added at 120 h of fermentation. Kinetics of extracellular and intracellular pigments were examined. Total pigment at the end of the fermentation using Triton X-100 was 27.7% higher than the control, confirming that the use of surfactants partially alleviated the product inhibition during the pigment production culture.

  6. Iris pigmentation and AC thresholds.

    Science.gov (United States)

    Roche, A F; Mukherjee, D; Chumlea, W C; Siervogel, R M

    1983-03-01

    Data from 160 White children were used to analyze possible associations between iris pigmentation and AC pure-tone thresholds. Iris pigmentation was graded from iris color using glass models of eyes, and AC thresholds were obtained under carefully controlled conditions. Analyses of variance using two groupings of iris color grades showed no evidence of an association between iris color grade and AC thresholds. Furthermore, inspection of arrays of the actual glass eye models, in conjunction with the order of mean thresholds at each test frequency, did not indicate the presence of an association between iris color grades and thresholds. It was concluded that while iris pigmentation may be related to some aspects of hearing ability, it does not appear to be related to AC thresholds in children.

  7. Non-destructive characterization of oriental porcelain glazes and blue underglaze pigments using μ-EDXRF, μ-Raman and VP-SEM

    International Nuclear Information System (INIS)

    Coutinho, M.L.; Muralha, V.S.F.; Mirao, J.; Veiga, J.P.

    2014-01-01

    The study of ancient materials with recognized cultural and economic value is a challenge to scientists and conservators, since it is usually necessary an approach through non-destructive techniques. Difficulties in establishing a correct analytical strategy are often significantly increased by the lack of knowledge on manufacture technologies and raw materials employed combined with the diversity of decay processes that may have acted during the lifetime of the cultural artefacts. A non-destructive characterization was performed on the glaze and underglaze pigments from a group of Chinese porcelain shards dated from the late Ming Dynasty (1368-1644) excavated at the Monastery of Santa Clara-a-Velha in Coimbra (Portugal). Chemical analysis was performed using micro-energy dispersive X-ray fluorescence spectrometry (μ-EDXRF). Mineralogical characterization was achieved by Raman microscopy (μ-Raman) and observation of small-surface crystallization dark spots with a metallic lustre in areas with high pigment concentration was done by variable pressure scanning electron microscopy (VP-SEM). Cobalt aluminate was identified as the blue underglaze pigment and a comparison of blue and dark blue pigments was performed by the ratio of Co, Mn, and Fe oxides, indicating a compositional difference between the two blue tonalities. Manganese oxide compounds were also identified as colouring agents in dark blue areas and surface migration of manganese compounds was verified. (orig.)

  8. Non-destructive characterization of oriental porcelain glazes and blue underglaze pigments using μ-EDXRF, μ-Raman and VP-SEM

    Science.gov (United States)

    Coutinho, M. L.; Muralha, V. S. F.; Mirão, J.; Veiga, J. P.

    2014-03-01

    The study of ancient materials with recognized cultural and economic value is a challenge to scientists and conservators, since it is usually necessary an approach through non-destructive techniques. Difficulties in establishing a correct analytical strategy are often significantly increased by the lack of knowledge on manufacture technologies and raw materials employed combined with the diversity of decay processes that may have acted during the lifetime of the cultural artefacts. A non-destructive characterization was performed on the glaze and underglaze pigments from a group of Chinese porcelain shards dated from the late Ming Dynasty (1368-1644) excavated at the Monastery of Santa Clara- a- Velha in Coimbra (Portugal). Chemical analysis was performed using micro-energy dispersive X-ray fluorescence spectrometry (μ-EDXRF). Mineralogical characterization was achieved by Raman microscopy (μ-Raman) and observation of small-surface crystallization dark spots with a metallic lustre in areas with high pigment concentration was done by variable pressure scanning electron microscopy (VP-SEM). Cobalt aluminate was identified as the blue underglaze pigment and a comparison of blue and dark blue pigments was performed by the ratio of Co, Mn, and Fe oxides, indicating a compositional difference between the two blue tonalities. Manganese oxide compounds were also identified as colouring agents in dark blue areas and surface migration of manganese compounds was verified.

  9. Non-destructive characterization of oriental porcelain glazes and blue underglaze pigments using μ-EDXRF, μ-Raman and VP-SEM

    Energy Technology Data Exchange (ETDEWEB)

    Coutinho, M.L. [Universidade Nova de Lisboa, REQUIMTE-CQFB, Faculdade de Ciencias e Tecnologia, Caparica (Portugal); Universidade Nova de Lisboa, Departamento de Conservacao e Restauro, Faculdade de Ciencias e Tecnologia, Caparica (Portugal); Muralha, V.S.F. [Universidade Nova de Lisboa, Research Unit VICARTE, Vidro e Ceramica para as Artes, Faculdade de Ciencias e Tecnologia, Caparica (Portugal); Mirao, J. [Universidade de Evora, Laboratorio HERCULES, Evora (Portugal); Veiga, J.P. [Universidade Nova de Lisboa, CENIMAT/I3N, Departamento de Ciencia dos Materiais, Faculdade de Ciencias e Tecnologia, Caparica (Portugal)

    2014-03-15

    The study of ancient materials with recognized cultural and economic value is a challenge to scientists and conservators, since it is usually necessary an approach through non-destructive techniques. Difficulties in establishing a correct analytical strategy are often significantly increased by the lack of knowledge on manufacture technologies and raw materials employed combined with the diversity of decay processes that may have acted during the lifetime of the cultural artefacts. A non-destructive characterization was performed on the glaze and underglaze pigments from a group of Chinese porcelain shards dated from the late Ming Dynasty (1368-1644) excavated at the Monastery of Santa Clara-a-Velha in Coimbra (Portugal). Chemical analysis was performed using micro-energy dispersive X-ray fluorescence spectrometry (μ-EDXRF). Mineralogical characterization was achieved by Raman microscopy (μ-Raman) and observation of small-surface crystallization dark spots with a metallic lustre in areas with high pigment concentration was done by variable pressure scanning electron microscopy (VP-SEM). Cobalt aluminate was identified as the blue underglaze pigment and a comparison of blue and dark blue pigments was performed by the ratio of Co, Mn, and Fe oxides, indicating a compositional difference between the two blue tonalities. Manganese oxide compounds were also identified as colouring agents in dark blue areas and surface migration of manganese compounds was verified. (orig.)

  10. INFLUENCE OF SURFACE-ACTIVE AGENT CONCENTRATION ON THE SPECTROPHOTOMETRIC BIOMASS ESTIMATION DURING SUBMERGED GROWTH OF Mycobacterium bovis

    Directory of Open Access Journals (Sweden)

    Sakai M.C.

    1997-01-01

    Full Text Available The influence of the surface-active agent Tween 80 (polyoxyethylene 20 sorbitan monoleate on the dispersed growth of Mycobacterium bovis - BCG - was studied. The slopes of the bacterial dry mass / absorbance curves, were significantly reduced, by the increase of the Tween 80 concentration in the medium. Such an influence was probably due to the effect Tween 80 had on the average size of bacterial clumps during the culture carried out in a bench fermenter

  11. {sup 137}Cs concentrations in Atlantic and western Antarctic surface waters: results of the 7th Ukrainian Antarctic Expedition, 2002

    Energy Technology Data Exchange (ETDEWEB)

    Gulin, S.B. [Institute of Biology of the Southern Seas (IBSS), 2, Nakhimov Av., Sevastopol, 99011 (Ukraine)]. E-mail: sergei@gulin.sebastopol.ua; Stokozov, N.A. [Institute of Biology of the Southern Seas (IBSS), 2, Nakhimov Av., Sevastopol, 99011 (Ukraine)

    2005-07-01

    The latitudinal distribution of {sup 137}Cs in the Atlantic-western Antarctic surface waters was studied during the 7th Ukrainian Antarctic Expedition in January-May 2002. The {sup 137}Cs concentrations have also been measured in the upper ice of the coastal glacier Woozle Hill located near the Ukrainian Antarctic station 'Akademik Vernadsky' (western Antarctica, 65 deg 15' S-64 deg 16' W). Comparison of these data with results of previous same-route expeditions SWEDARP (Swedish Antarctic Research Expedition, 1988/1989) and the French R/V 'Jeanne d'Arc' (1992/1993), has shown practically parallel changes of {sup 137}Cs surface concentrations between 40 deg N and 20 deg S, pointing to decrease of {sup 137}Cs radioactivity at these latitudes with an apparent half-life of 10-15 years (12.5{+-}2.1 years on average). This suggests that decrease of {sup 137}Cs surface concentration within this latitude band is controlled, besides the radioactive decay of {sup 137}Cs (half-life=30 years), by vertical mixing of the upper water masses. South of 20 deg S, the {sup 137}Cs concentrations in surface water have decreased more rapidly because of the influence of the less contaminated Antarctic waters. At 50-60 deg S and near the Antarctic coast, the {sup 137}Cs activity in 2002 was similar to those measured during the SWEDARP and 'Jeanne d'Arc' expeditions, suggesting an additional input of {sup 137}Cs to these waters from the melted ice from the adjacent glaciers.

  12. Water erosion in surface soil conditions: runoff velocity, concentration and D50 index of sediments in runoff

    Directory of Open Access Journals (Sweden)

    Júlio César Ramos

    2016-06-01

    Full Text Available ABSTRACT Water erosion and contamination of water resources are influenced by concentration and diameter of sediments in runoff. This study aimed to quantify runoff velocity and concentration and the D50 index of sediments in runoff under different soil surface managements, in the following treatments: i cropped systems: no-tilled soil covered by ryegrass (Lolium multiflorum Lam. residue, with high soil cover and minimal roughness (HCR; no tilled soil covered by vetch (Vicia sativa L. residue, with high soil cover and minimal roughness (HCV; chiseled soil after ryegrass crop removing the above-ground residues and keeping only the root system, with high roughness (HRR; chiseled soil after vetch crop removing the above-ground residues and keeping only the root system, with high roughness (HRV; ii bare and chiseled soil, with high roughness (BHR. The research was conducted on a Humic Dystrupept under simulated rainfall. The design was completely randomized and each treatment was replicated twice. Eight rainfall events of controlled intensity (65 mm h−1 were applied to each treatment for 90 minutes. The D50 index, runoff velocity and sediment concentration were influenced by crop and soil management. Runoff velocity was more intensely reduced by cover crop residues than by surface roughness. Regardless of surface condition, the D50 index and concentration of sediment in runoff were lower under ryegrass than vetch crop. Runoff velocity and the D50 index were exponentially and inversely correlated with soil cover by residues and with surface roughness, while the D50 index was positively and exponentially correlated with runoff velocity.

  13. Detection of low-concentration contaminants in solution by exploiting chemical derivatization in surface-enhanced Raman spectroscopy.

    Science.gov (United States)

    Hardy, Mike; Doherty, Matthew D; Krstev, Igor; Maier, Konrad; Möller, Torgny; Müller, Gerhard; Dawson, Paul

    2014-09-16

    A simple derivatization methodology is shown to extend the application of surface-enhanced Raman spectroscopy (SERS) to the detection of trace concentration of contaminants in liquid form. Normally in SERS the target analyte species is already present in the molecular form in which it is to be detected and is extracted from solution to occupy sites of enhanced electromagnetic field on the substrate by means of chemisorption or drop-casting and subsequent evaporation of the solvent. However, these methods are very ineffective for the detection of low concentrations of contaminant in liquid form because the target (ionic) species (a) exhibits extremely low occupancy of enhancing surface sites in the bulk liquid environment and (b) coevaporates with the solvent. In this study, the target analyte species (acid) is detected via its solid derivative (salt) offering very significant enhancement of the SERS signal because of preferential deposition of the salt at the enhancing surface but without loss of chemical discrimination. The detection of nitric acid and sulfuric acid is demonstrated down to 100 ppb via reaction with ammonium hydroxide to produce the corresponding ammonium salt. This yields an improvement of ~4 orders of magnitude in the low-concentration detection limit compared with liquid phase detection.

  14. Surrogate measurement of chlorine concentration on steel surfaces by alkali element detection via laser-induced breakdown spectroscopy

    Science.gov (United States)

    Xiao, X.; Le Berre, S.; Hartig, K. C.; Motta, A. T.; Jovanovic, I.

    2017-04-01

    Chlorine can play an important role in the process of stress corrosion cracking of dry cask storage canisters for used nuclear fuel, which are frequently located in marine environments. It is of significant interest to determine the surface concentration of chlorine on the stainless steel canister surface, but measurements are often limited by difficult access and challenging conditions, such as high temperature and high radiation fields. Laser-induced breakdown spectroscopy (LIBS) could enable chlorine concentration measurements while meeting the other constraints of this application, but suffers from high excitation energy of chlorine and the interference of the atomic emission lines of iron, thus limiting the sensitivity of detection, especially when LIBS has to be delivered over an optical fiber. We demonstrate that chlorine surface concentrations in the range of 0.5-100 mg/m2 can be inferred by the detection and quantification of sodium contained in chlorine salts if the speciation and neutralization of salts are not of major concern, whereas minor components of sea salt such as magnesium and potassium are less attractive as surrogates for chlorine due to the lower sensitivity of LIBS for their detection and quantification. The limit of detection, measurement accuracy, and other features and limitations of this surrogate measurement approach are discussed.

  15. Light Absorption by Suspended Particles in the Red Sea: Effect of Phytoplankton Community Size Structure and Pigment Composition

    Science.gov (United States)

    Kheireddine, Malika; Ouhssain, Mustapha; Organelli, Emanuele; Bricaud, Annick; Jones, Burton H.

    2018-02-01

    The light absorption properties of phytoplankton (aph(λ)) and nonalgal particles (anap(λ)) associated with phytoplankton pigments were analyzed across the Red Sea, in the upper 200 m depth, between October 2014 and August 2016. The contribution by nonalgal particles to the total particulate light absorption (aph(λ) + anap(λ)) was highly variable (23 ± 17% at 440 nm) and no relationship between anap(440) and chlorophyll a concentration, [TChl a], was observed. Phytoplankton-specific phytoplankton absorption coefficients at 440 and 676 nm for a given [TChl a], aph*(440), and aph∗(676) were slightly higher than those derived from average relationships for open ocean waters within the surface layer as well as along the water column. Variations in the concentration of photosynthetic and photoprotective pigments were noticeable by changes in phytoplankton community size structure as well as in aph∗(λ). This study revealed that a higher proportion of picophytoplankton and an increase in photoprotective pigments (mainly driven by zeaxanthin) tended to be responsible for the higher aph∗(λ) values found in the Red Sea as compared to other oligotrophic regions with similar [TChl a]. Understanding this variability across the Red Sea may help improve the accuracy of biogeochemical parameters, such as [TChl a], derived from in situ measurements and ocean color remote sensing at a regional scale.

  16. Light Absorption by Suspended Particles in the Red Sea: Effect of Phytoplankton Community Size Structure and Pigment Composition

    KAUST Repository

    Kheireddine, Malika

    2018-01-10

    The light absorption properties of phytoplankton (aph(λ)) and non-algal particles (anap(λ)) associated with phytoplankton pigments were analyzed across the Red Sea, in the upper 200 m depth, between October 2014 and August 2016. The contribution by non-algal particles to the total particulate light absorption (aph(λ)+ anap(λ)) was highly variable (23 ± 17% at 440 nm) and no relationship between anap(440) and chlorophyll a concentration, [TChl a], was observed. Phytoplankton specific phytoplankton absorption coefficients at 440 and 676 nm for a given [TChl a], aph*(440) and aph*(676), were slightly higher than those derived from average relationships for open ocean waters within the surface layer as well as along the water column. Variations in the concentration of photosynthetic and photoprotective pigments were noticeable by changes in phytoplankton community size structure as well as in aph*(λ). This study revealed that a higher proportion of picophytoplankton and an increase in photoprotective pigments (mainly driven by zeaxanthin) tended to be responsible for the higher aph*(λ) values found in the Red Sea as compared to other oligotrophic regions with similar [TChl a]. Understanding this variability across the Red Sea may help improve the accuracy of biogeochemical parameters, such as [TChl a], derived from in situ measurements and ocean color remote sensing at a regional scale.

  17. Quantification of Hydrogen Concentrations in Surface and Interface Layers and Bulk Materials through Depth Profiling with Nuclear Reaction Analysis.

    Science.gov (United States)

    Wilde, Markus; Ohno, Satoshi; Ogura, Shohei; Fukutani, Katsuyuki; Matsuzaki, Hiroyuki

    2016-03-29

    Nuclear reaction analysis (NRA) via the resonant (1)H((15)N,αγ)(12)C reaction is a highly effective method of depth profiling that quantitatively and non-destructively reveals the hydrogen density distribution at surfaces, at interfaces, and in the volume of solid materials with high depth resolution. The technique applies a (15)N ion beam of 6.385 MeV provided by an electrostatic accelerator and specifically detects the (1)H isotope in depths up to about 2 μm from the target surface. Surface H coverages are measured with a sensitivity in the order of ~10(13) cm(-2) (~1% of a typical atomic monolayer density) and H volume concentrations with a detection limit of ~10(18) cm(-3) (~100 at. ppm). The near-surface depth resolution is 2-5 nm for surface-normal (15)N ion incidence onto the target and can be enhanced to values below 1 nm for very flat targets by adopting a surface-grazing incidence geometry. The method is versatile and readily applied to any high vacuum compatible homogeneous material with a smooth surface (no pores). Electrically conductive targets usually tolerate the ion beam irradiation with negligible degradation. Hydrogen quantitation and correct depth analysis require knowledge of the elementary composition (besides hydrogen) and mass density of the target material. Especially in combination with ultra-high vacuum methods for in-situ target preparation and characterization, (1)H((15)N,αγ)(12)C NRA is ideally suited for hydrogen analysis at atomically controlled surfaces and nanostructured interfaces. We exemplarily demonstrate here the application of (15)N NRA at the MALT Tandem accelerator facility of the University of Tokyo to (1) quantitatively measure the surface coverage and the bulk concentration of hydrogen in the near-surface region of a H2 exposed Pd(110) single crystal, and (2) to determine the depth location and layer density of hydrogen near the interfaces of thin SiO2 films on Si(100).

  18. Chicken feather peptone: A new alternative nitrogen source for pigment production by Monascus purpureus.

    Science.gov (United States)

    Orak, Tugba; Caglar, Ozge; Ortucu, Serkan; Ozkan, Hakan; Taskin, Mesut

    2018-04-10

    Peptones are accepted as one of the most favourable nitrogen sources supporting pigment synthesis in Monascus purpureus. The present study was performed to test the feasibility of chicken feather peptone (CFP) as nitrogen source for pigment production from M. purpureus ATCC16365. CFP was compared with fish peptone (FP) and protease peptone (PP) in order to elucidate its effectiveness on pigment production. CFP was prepared from waste feathers using hydrolysis (KOH) and neutralization (H 2 SO 4 ) methods. The protein content of CFP was determined as 67.2 g/100 g. Optimal concentrations of CFP and glucose for pigment production were determined as 3 and 20 g/L, respectively. A medium pH of 5.5 and an incubation period of 7-days were found to be more favourable for pigment production. In CFP, PP and FP media, yellow pigment absorbances were 2.819, 2.870 and 2.831, red pigment absorbances were 2.709, 2.304 and 2.748, and orange pigment absorbances were 2.643, 2.132 and 2.743, respectively. Sugar consumption and mycelia growth showed the similar trends in CFP, FP and PP media. This study indicates that the peptone from chicken feathers may be a good nutritional substrate for pigment production from M. purpureus. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. Surface air concentration and deposition of lead-210 in French Guiana: two years of continuous monitoring

    International Nuclear Information System (INIS)

    Melieres, Marie-Antoinette; Pourchet, Michel; Richard, Sandrine

    2003-01-01

    To make up for the lack of data on 210 Pb aerosol deposition in tropical regions and to use this radionuclide as an aerosol tracer,a monitoring station was run for two years at Petit-Saut, French Guiana. Lead-210 concentration in air at ground level was monitored continuously together with atmospheric total deposition. The air concentration has a mean value of 0.23±0.02 mBq m -3 during both wet and dry seasons, and it is only weakly affected by the precipitation mechanism. This result was unexpected in a wet tropical region, with a high precipitation rate. In contrast, deposition clearly correlates with precipitation for low/moderate rainfall ( -2 y -1 . This provides a procedure fo estimating this mean flux at other sites in French Guiana

  20. Simplified method for preparation of concentrated exoproteins produced by Staphylococcus aureus grown on surface of cellophane bag containing liquid medium.

    Science.gov (United States)

    Ikigai, H; Seki, K; Nishihara, S; Masuda, S

    1988-01-01

    A simplified method for preparation of concentrated exoproteins including protein A and alpha-toxin produced by Staphylococcus aureus was successfully devised. The concentrated proteins were obtained by cultivating S. aureus organisms on the surface of a liquid medium-containing cellophane bag enclosed in a sterilized glass flask. With the same amount of medium, the total amount of proteins obtained by the method presented here was identical with that obtained by conventional liquid culture. The concentration of proteins obtained by the method, however, was high enough to observe their distinct bands stained on polyacrylamide gel electrophoresis. This method was considered quite useful not only for large-scale cultivation for the purification of staphylococcal proteins but also for small-scale study using the proteins. The precise description of the method was presented and its possible usefulness was discussed.

  1. A space-charge treatment of the increased concentration of reactive species at the surface of a ceria solid solution

    Energy Technology Data Exchange (ETDEWEB)

    Zurhelle, Alexander F.; Souza, Roger A. de [Institute of Physical Chemistry, RWTH Aachen University (Germany); Tong, Xiaorui; Mebane, David S. [Department of Mechanical and Aerospace Engineering, West Virginia University, Morgantown, WV (United States); Klein, Andreas [Institute of Materials Science, TU Darmstadt (Germany)

    2017-11-13

    A space-charge theory applicable to concentrated solid solutions (Poisson-Cahn theory) was applied to describe quantitatively as a function of temperature and oxygen partial pressure published data obtained by in situ X-ray photoelectron spectroscopy (XPS) for the concentration of Ce{sup 3+} (the reactive species) at the surface of the oxide catalyst Ce{sub 0.8}Sm{sub 0.2}O{sub 1.9}. In contrast to previous theoretical treatments, these calculations clearly indicate that the surface is positively charged and compensated by an attendant negative space-charge zone. The high space-charge potential that develops at the surface (>0.8 V) is demonstrated to be hardly detectable by XPS measurements because of the short extent of the space-charge layer. This approach emphasizes the need to take into account defect interactions and to allow deviations from local charge neutrality when considering the surfaces of oxide catalysts. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  2. Dual-Wavelength Surface Plasmon Resonance for Determining the Size and Concentration of Sub-Populations of Extracellular Vesicles.

    Science.gov (United States)

    Rupert, Deborah L M; Shelke, Ganesh V; Emilsson, Gustav; Claudio, Virginia; Block, Stephan; Lässer, Cecilia; Dahlin, Andreas; Lötvall, Jan O; Bally, Marta; Zhdanov, Vladimir P; Höök, Fredrik

    2016-10-04

    Accurate concentration determination of subpopulations of extracellular vesicles (EVs), such as exosomes, is of importance both in the context of understanding their fundamental biological role and of potentially using them as disease biomarkers. In principle, this can be achieved by measuring the rate of diffusion-limited mass uptake to a sensor surface modified with a receptor designed to only bind the subpopulation of interest. However, a significant error is introduced if the targeted EV subpopulation has a size, and thus hydrodynamic diffusion coefficient, that differs from the mean size and diffusion coefficient of the whole EV population and/or if the EVs become deformed upon binding to the surface. We here demonstrate a new approach to determine the mean size (or effective film thickness) of bound nanoparticles, in general, and EV subpopulation carrying a marker of interest, in particular. The method is based on operating surface plasmon resonance simultaneously at two wavelengths with different sensing depths and using the ratio of the corresponding responses to extract the particle size on the surface. By estimating in this way the degree of deformation of adsorbed EVs, we markedly improved their bulk concentration determination and showed that EVs carrying the exosomal marker CD63 correspond to not more than around 10% of the EV sample.

  3. Formation of Reversible Solid Electrolyte Interface on Graphite Surface from Concentrated Electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Dongping; Tao, Jinhui; Yan, Pengfei; Henderson, Wesley A.; Li, Qiuyan; Shao, Yuyan; Helm, Monte L.; Borodin, Oleg; Graff, Gordon L.; Polzin, Bryant; Wang, Chong-Min; Engelhard, Mark; Zhang, Ji-Guang; De Yoreo, James J.; Liu, Jun; Xiao, Jie

    2017-02-10

    Interfacial phenomena have always been key determinants for the performance of energy storage technologies. The solid electrolyte interfacial (SEI) layer, pervasive on the surfaces of battery electrodes for numerous chemical couples, directly affects the ion transport, charge transfer and lifespan of the entire energy system. Almost all SEI layers, however, are unstable resulting in the continuous consumption of the electrolyte. Typically, this leads to the accumulation of degradation products on/restructuring of the electrode surface and thus increased cell impedance, which largely limits the long-term operation of the electrochemical reactions. Herein, a completely new SEI formation mechanism has been discovered, in which the electrolyte components reversibly self-assemble into a protective surface coating on a graphite electrode upon changing the potential. In contrast to the established wisdom regarding the necessity of employing the solvent ethylene carbonate (EC) to form a protective SEI layer on graphite, a wide range of EC-free electrolytes are demonstrated for the reversible intercalation/deintercalation of Li+ cations within a graphite lattice, thereby providing tremendous flexibility in electrolyte tailoring for battery couples. This novel finding is broadly applicable and provides guidance for how to control interfacial reactions through the relationship between ion aggregation and solvent decomposition at polarized interfaces.

  4. Obtention of ceramic pigments with residue from electroplating

    International Nuclear Information System (INIS)

    Boss, A.; Kniess, C.T.; Aguiar, B.M. de; Prates, P.B.; Milanez, K.

    2011-01-01

    The incorporation of industrial residues in industrial processes opens up new business opportunities and reduces the volume of extraction of raw materials, preserving natural resources, which are limited. An important residue is the mud from galvanic industry, consisting of alkali and transition metals. According to NBR 10004/2004, this residue can be classified as Class I (hazardous), depending on the concentration of metals present in the mud. This paper proposes a method for reusing the residue from electroplating in ceramic pigments. The characterization of residual plating was obtained by chemical analysis, mineralogical analysis and pH measurements. The electroplating waste was incorporated in different percentages on a standard pigment formula of industrial ceramic, consisting mainly of Zn, Fe and Cr. The obtained pigments were applied in ceramic glazes to colorimetric and visual analysis, which showed good results with the addition of up to 15% of industrial waste. (author)

  5. Interactions of natural resins and pigments in works of art.

    Science.gov (United States)

    Poli, Tommaso; Piccirillo, Anna; Nervo, Marco; Chiantore, Oscar

    2017-10-01

    The degradation process involving the formation of metal soaps in drying oils is a well-known problem due to cations from pigments reacting with free fatty acids from the oil. The aggregation of these carboxylates in semi-crystalline structures can lead to eruptions through the paint layers and 'blooming' on the surface. In this work, the metal soaps formation in presence of natural resins has been assessed and studied by means of Fourier transform infrared spectroscopy with experiments concerning the ageing of drying oil and different natural resins (shellac, dammar and colophony) in the presence of common historic pigments (smalt, ochre, umber, azurite, lead white, zinc white and titanium white). Mixtures of resins and pigments have been exposed to photo-ageing in solar box up to 1000h, thermal ageing at 50°C up to 1100h and 6month of room conditions exposure as reference. The decrease in the intensity of the carbonyl band in the spectra, as well as the contemporary increase of the metal carboxylates (in the range from 1500 to 1650cm -1 ) absorption bands, were used as the main indicators of metal soap formation. It has been observed that some pigments, particularly zinc white and smalt, present a 'catalytic' effect favouring the simultaneous formation of associated oxalates. The formation of oxalates and different degradation products from natural resins in the presence of pigments is particularly important, as it deeply affects the removability of varnishes and, more generally, the cleaning processes. Moreover, it permanently modifies the interface between painting and varnish layers as well as the aesthetic aspects of the painted surfaces. The influence of natural resins reactivity with pigments and their role in the oxalate formation is an issue still unexplored. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Influence of geology on arsenic concentrations in ground and surface water in central Lesvos, Greece.

    Science.gov (United States)

    Aloupi, Maria; Angelidis, Michael O; Gavriil, Apostolos M; Koulousaris, Michael; Varnavas, Soterios P

    2009-04-01

    The occurrence of As was studied in groundwater used for human consumption and irrigation, in stream water and sediments and in water from thermal springs in the drainage basin of Kalloni Gulf, island of Lesvos, Greece, in order to investigate the potential influence of the geothermal field of Polichnitos-Lisvori on the ground and surface water systems of the area. Total dissolved As varied in the range geology exerts a determinant influence on As geochemical behaviour. On the other hand, the geothermal activity manifested in the area of Polichnitos-Lisvori does not affect the presence of As in groundwater and streams.

  7. Primary pigmented nodular adrenocortical disease

    Directory of Open Access Journals (Sweden)

    Marie T Manipadam

    2011-01-01

    Full Text Available Primary pigmented nodular adrenocortical disease (PPNAD is a rare cause of ACTH-independent Cushing′s syndrome and has characteristic gross and microscopic pathologic findings. We report a case of PPNAD in a 15-year-old boy, which was not associated with Carney′s complex. Bilateral adrenalectomy is the treatment of choice.

  8. Examination of Surface Deposits on Oldbury Reactor Core Graphite to Determine the Concentration and Distribution of 14C.

    Directory of Open Access Journals (Sweden)

    Liam Payne

    Full Text Available Pile Grade A graphite was used as a moderator and reflector material in the first generation of UK Magnox nuclear power reactors. As all of these reactors are now shut down there is a need to examine the concentration and distribution of long lived radioisotopes, such as 14C, to aid in understanding their behaviour in a geological disposal facility. A selection of irradiated graphite samples from Oldbury reactor one were examined where it was observed that Raman spectroscopy can distinguish between underlying graphite and a surface deposit found on exposed channel wall surfaces. The concentration of 14C in this deposit was examined by sequentially oxidising the graphite samples in air at low temperatures (450°C and 600°C to remove the deposit and then the underlying graphite. The gases produced were captured in a series of bubbler solutions that were analysed using liquid scintillation counting. It was observed that the surface deposit was relatively enriched with 14C, with samples originating lower in the reactor exhibiting a higher concentration of 14C. Oxidation at 600°C showed that the remaining graphite material consisted of two fractions of 14C, a surface associated fraction and a graphite lattice associated fraction. The results presented correlate well with previous studies on irradiated graphite that suggest there are up to three fractions of 14C; a readily releasable fraction (corresponding to that removed by oxidation at 450°C in this study, a slowly releasable fraction (removed early at 600°C in this study, and an unreleasable fraction (removed later at 600°C in this study.

  9. Kinetic of orange pigment production from Monascus ruber on submerged fermentation.

    Science.gov (United States)

    Vendruscolo, Francielo; Schmidell, Willibaldo; de Oliveira, Débora; Ninow, Jorge Luiz

    2017-01-01

    Pigments produced by species of Monascus have been used to coloring rice, meat, sauces, wines and beers in East Asian countries. Monascus can produce orange (precursor), yellow and red pigments. Orange pigments have low solubility in culture media and when react with amino groups they become red and largely soluble. The orange pigments are an alternative to industrial pigment production because the low solubility facilitates the downstream operations. The aim of this work was to study the kinetic on the production of orange pigments by Monascus ruber CCT 3802. The shaking frequency of 300 rpm was favorable to production, whereas higher shaking frequencies showed negative effect. Pigment production was partially associated with cell growth, the critical dissolved oxygen concentration was between 0.894 and 1.388 mgO 2  L -1 at 30 °C, and limiting conditions of dissolved oxygen decreased the production of orange pigments. The maintenance coefficient (mo) and the conversion factor of oxygen in biomass (Yo) were 18.603 mgO 2  g x -1  h -1 and 3.133 g x  gO 2 -1 and the consideration of these parameters in the oxygen balance to estimate the biomass concentration provided good fits to the experimental data.

  10. Quantitative X-ray diffraction and fluorescence analysis of paint pigment systems : final report.

    Science.gov (United States)

    1978-01-01

    This study attempted to correlate measured X-ray intensities with concentrations of each member of paint pigment systems, thereby establishing calibration curves for the quantitative analyses of such systems.

  11. Surface air concentration and deposition of lead-210 in French Guiana: two years of continuous monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Melieres, Marie-Antoinette E-mail: melieres@glaciog.ujf-grenoble.fr; Pourchet, Michel; Richard, Sandrine

    2003-07-01

    To make up for the lack of data on {sup 210}Pb aerosol deposition in tropical regions and to use this radionuclide as an aerosol tracer,a monitoring station was run for two years at Petit-Saut, French Guiana. Lead-210 concentration in air at ground level was monitored continuously together with atmospheric total deposition. The air concentration has a mean value of 0.23{+-}0.02 mBq m{sup -3} during both wet and dry seasons, and it is only weakly affected by the precipitation mechanism. This result was unexpected in a wet tropical region, with a high precipitation rate. In contrast, deposition clearly correlates with precipitation for low/moderate rainfall (<15 cm per 15-day), while this correlation is masked by strong fluctuations at high rainfall. The estimated mean annual deposition over the last ten years is 163{+-}75 Bq m{sup -2} y{sup -1}. This provides a procedure fo estimating this mean flux at other sites in French Guiana.

  12. Source contribution analysis of surface particulate polycyclic aromatic hydrocarbon concentrations in northeastern Asia by source–receptor relationships

    International Nuclear Information System (INIS)

    Inomata, Yayoi; Kajino, Mizuo; Sato, Keiichi; Ohara, Toshimasa; Kurokawa, Jun-ichi; Ueda, Hiromasa; Tang, Ning; Hayakawa, Kazuichi; Ohizumi, Tsuyoshi; Akimoto, Hajime

    2013-01-01

    We analyzed the source–receptor relationships for particulate polycyclic aromatic hydrocarbon (PAH) concentrations in northeastern Asia using an aerosol chemical transport model. The model successfully simulated the observed concentrations. In Beijing (China) benzo[a]pyren (BaP) concentrations are due to emissions from its own domain. In Noto, Oki and Tsushima (Japan), transboundary transport from northern China (>40°N, 40–60%) and central China (30–40°N, 10–40%) largely influences BaP concentrations from winter to spring, whereas the relative contribution from central China is dominant (90%) in Hedo. In the summer, the contribution from Japanese domestic sources increases (40–80%) at the 4 sites. Contributions from Japan and Russia are additional source of BaP over the northwestern Pacific Ocean in summer. The contribution rates for the concentrations from each domain are different among PAH species depending on their particulate phase oxidation rates. Reaction with O 3 on particulate surfaces may be an important component of the PAH oxidation processes. -- Highlights: •Source–receptor analysis was conducted for investigating PAHs in northeast Asia. •In winter, transboundary transport from China is large contribution in leeward. •Relative contribution from Korea, Japan, and eastern Russia is increased in summer. •This seasonal variation is strongly controlled by the meteorological conditions. •The transport distance is different among PAH species. -- Transboundary transport of PAHs in northeast Asia was investigated by source–receptor analysis

  13. Optimization of Xanthan Gum Production from Grape Juice Concentrate Using Plackett-Burman Design and Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Tahereh Ghashghaei

    2016-01-01

    Full Text Available Low grade grape juice concentrate was used as carbon source for xanthan production. Significant factors affecting xanthan concentration, productivity and viscosity were investigated using Plackett-Burman Design. Based on the obtained results, carbon and nitrogen concentrations, inoculum size and agitation rate, were assumed as significant factors. Broth culture viscosity and xanthan concentration were optimized using Response Surface Methodology with four independent variables: carbon source (30, 40, 50 g l-1, ammonium sulfate as nitrogen source (0.5, 1.25, 2 g l-1, agitation (150, 200, 250 rpm and inoculum size (5, 10, 15% v v-1. Optimum level for each factor was obtained by desirability function approach. The average of xanthan gum production and its viscosity under optimized conditions were recorded as 14.35 g l-1 and 1268 cP, respectively. The average yield of production and productivity of xanthan within 72 h under optimized conditions were 35% and 0.19 g l-1 h-1, respectively. The current study showed the potential of low-grade grape juice concentrate as an economic carbon source for xanthan gum production.

  14. Distributions and concentrations of thallium in surface waters of a region impacted by historical metal mining (Cornwall, UK).

    Science.gov (United States)

    Tatsi, Kristi; Turner, Andrew

    2014-03-01

    Thallium is a highly toxic heavy metal whose concentrations and distributions in the aquatic environment are poorly defined. In this study, concentrations of aqueous and total Tl have been measured in water samples from a variety of rivers and effluents (the latter related to historical metal mining) in the county of Cornwall, SW England. Aqueous concentrations ranged from about 13 ng L(-1) in a river whose catchment contained no metal mines to 2,640 ng L(-1) in water abstracted directly from an abandoned mine shaft. Concentrations of Tl in rivers were greatest in the vicinity of mine-related effluents, with a maximum value measured of about 770 ng L(-1). Thallium was not efficiently removed by the conventional, active treatment of mine water, and displayed little interaction with suspended particles. Its mobility in surface waters, coupled with concentrations that are close to a quality guideline of 800 ng L(-1), is cause for concern. Accordingly, we recommend that the metal is more closely monitored in this and other regions impacted by mining activities. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Regional patterns of pesticide concentrations in surface waters of New York in 1997

    Science.gov (United States)

    Phillips, P.J.; Eckhardt, D.A.; Freehafer, D.A.; Wall, G.R.; Ingleston, H.H.

    2002-01-01

    The predominant mixtures of pesticides found in New York surface waters consist of five principal components. First, herbicides commonly used on corn (atrazine, metolachlor, alachlor, cyanazine) and a herbicide degradate (deethylatrazine) were positively correlated to a corn-herbicide component, and watersheds with the highest corn-herbicide component scores were those in which large amounts of row crops are grown. Second, two insecticides (diazinon and carbaryl) and one herbicide (prometon) widely used in urban and residential settings were positively correlated to an urban/residential component. Watersheds with the highest urban/residential component scores were those with large amounts of urban and residential land use. A third component was related to two herbicides (EPTC and cyanazine) used on dry beans and corn, the fourth to an herbicide (simazine) and an insecticide (carbaryl) commonly used in orchards and vineyards, and the fifth to an herbicide (DCPA). Results of this study indicate that this approach can be used to: (1) identify common mixtures of pesticides in surface waters, (2) relate these mixtures to land use and pesticide applications, and (3) indicate regions where these mixtures of pesticides are commonly found.

  16. Simulating Exposure Concentrations of Engineered Nanomaterials in Surface Water Systems: Release of WASP8

    Science.gov (United States)

    Knightes, C. D.; Bouchard, D.; Zepp, R. G.; Henderson, W. M.; Han, Y.; Hsieh, H. S.; Avant, B. K.; Acrey, B.; Spear, J.

    2017-12-01

    The unique properties of engineered nanomaterials led to their increased production and potential release into the environment. Currently available environmental fate models developed for traditional contaminants are limited in their ability to simulate nanomaterials' environmental behavior. This is due to an incomplete understanding and representation of the processes governing nanomaterial distribution in the environment and by scarce empirical data quantifying the interaction of nanomaterials with environmental surfaces. The well-known Water Quality Analysis Simulation Program (WASP) was updated to incorporate nanomaterial-specific processes, specifically hetero-aggregation with particulate matter. In parallel with this effort, laboratory studies were used to quantify parameter values parameters necessary for governing processes in surface waters. This presentation will discuss the recent developments in the new architecture for WASP8 and the newly constructed Advanced Toxicant Module. The module includes advanced algorithms for increased numbers of state variables: chemicals, solids, dissolved organic matter, pathogens, temperature, and salinity. This presentation will focus specifically on the incorporation of nanomaterials, with the applications of the fate and transport of hypothetical releases of Multi-Walled Carbon Nanotubes (MWCNT) and Graphene Oxide (GO) into the headwaters of a southeastern US coastal plains river. While this presentation focuses on nanomaterials, the advanced toxicant module can also simulate metals and organic contaminants.

  17. 21 CFR 73.352 - Paracoccus pigment.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Paracoccus pigment. 73.352 Section 73.352 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.352 Paracoccus pigment. (a) Identity. (1) The color additive paracoccus pigment consists of the heat-killed, dried cells of a nonpathogenic and nontoxicogenic strain of...

  18. Swapping one red pigment for another.

    Science.gov (United States)

    Davies, Kevin M

    2015-01-01

    Betalains are bright red and yellow pigments, which are produced in only one order of plants, the Caryophyllales, and replace the more familiar anthocyanin pigments. The evolutionary origin of betalain production is a mystery, but a new study has identified the first regulator of betalain production and discovered a previously unknown link between the two pigment pathways.

  19. Seperation, identification and analysis of pigment (melanin ...

    African Journals Online (AJOL)

    Nine strains among 180 Streptomyces isolates produce a diffusible dark brown pigment on both peptone-yeast extract agar and synthetic tyrosine-agar. They also show the positive reaction to Ltyrosine or L-dopa substrates. The pigment has been referred to be as merely as dark brown watersoluble pigment, as melanoid or ...

  20. Platinum-based anticancer drugs in waste waters of a major UK hospital and predicted concentrations in recipient surface waters.

    Science.gov (United States)

    Vyas, Nitin; Turner, Andrew; Sewell, Graham

    2014-09-15

    Concentrations of the cytotoxic platinum-based anticancer drugs, as total Pt, have been measured over a three week period in one of the main drains and in the effluent of the oncology ward of a major UK hospital (Derriford, Plymouth). Concentrations of Pt were highly variable in both discharges, and ranged from about 0.02 to 140 μg L(-1) in the oncology effluent and from about 0.03 to 100 μg L(-1) in the main drain. A comparison of drug administration figures over the study period with an estimate of the quantity of Pt discharged through the drains suggests that about 22% of total Pt is emitted to the environment from the hospital with the remainder being discharged by treated patients in the wider community. Administration figures for the three Pt-based drugs used in the hospital (cisplatin, carboplatin and oxaliplatin) coupled with published measurements on the removal of the drugs by conventional sewage treatment allowed the concentrations of Pt arising from each drug to be predicted in recipient surface waters as a function of water flow rate. For conditions representative of the region under study, concentrations of total Pt between a few tens and in excess of 100 pg L(-1) are predicted, with the principal form of the metal occurring as carboplatin and its metabolites. Although predicted concentrations are below EMEA guidelines warranting further risk assessment, the presence of substances in surface waters that are potentially carcinogenic, mutagenic and teratogenic and yet whose environmental effects are not understood is cause for concern. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Eggshell Biliverdin and Protoporphyrin Pigments in a Songbird: Are They Derived from Erythrocytes, Blood Plasma, or the Shell Gland?

    Science.gov (United States)

    Hargitai, Rita; Boross, Nóra; Hámori, Susanne; Neuberger, Eszter; Nyiri, Zoltán

    Biliverdin and protoporphyrin pigments are deposited into the eggshell when the developing egg is in the shell gland. However, the site of synthesis of eggshell pigments is still uncertain, although it may influence the possible costs and potential functions of eggshell coloration in avian species. Eggshell pigments may be derived from red blood cells or be produced in other organs and then transferred to the shell gland, or they may be synthesized de novo in the shell gland. We studied in the canary (Serinus canaria) whether eggshell blue-green and brown pigmentations are associated with experimentally elevated anemia, female hematocrit level, immature erythrocyte percentage, and feces and plasma pigment levels during egg laying to find out the possible origin of eggshell pigments. We found no significant effects of hematocrit level or experimentally elevated anemia on intensity of eggshell blue-green and brown pigmentations; therefore, we consider it less likely that eggshell pigments are derived from erythrocytes. In addition, we found no significant associations between female feces biliverdin concentration during egg laying and intensity of eggshell blue-green pigmentation, suggesting that eggshell biliverdin may not originate from the spleen or liver. We found a negative association between plasma and feces protoporphyrin concentrations during egg laying and eggshell brown chroma. This result suggests that an increased production of protoporphyrin in the liver, which could have elevated plasma and feces protoporphyrin concentrations, could inhibit eggshell protoporphyrin pigmentation, probably through affecting enzymatic activities. We suggest that both pigments are produced de novo in the shell gland in the canary, but circulating pigment levels may influence shell gland pigment synthesis, thus connecting the physiological status of the female to eggshell coloration.

  2. To Investigate the Absorption, Dynamic Contact Angle and Printability Effects of Synthetic Zeolite Pigments in an Inkjet Receptive Coating

    Science.gov (United States)

    Jalindre, Swaraj Sunil

    Ink absorption performance in inkjet receptive coatings containing synthetic zeolite pigments was studied. Coating pigment pore and particle size distribution are the key parameters that influence in modifying media surface properties, thus affecting the rate of ink penetration and drying time (Scholkopf, et al. 2004). The primary objective of this study was: (1) to investigate the synthetic zeolite pigment effects on inkjet ink absorption, dynamic contact angle and printability, and (2) to evaluate these novel synthetic zeolite pigments in replacing the fumed silica pigments in conventional inkjet receptive coatings. In this research study, single pigment coating formulations (in equal P:B ratio) were prepared using microporous synthetic zeolite pigments (5A, Organophilic and 13X) and polyvinyl alcohol (PVOH) binder. The laboratory-coated samples were characterized for absorption, air permeance, roughness, drying time, wettability and print fidelity. Based on the rheological data, it was found that the synthetic zeolite formulated coatings depicted a Newtonian flow behavior at low shear; while the industry accepted fumed silica based coatings displayed a characteristically high pseudoplastic flow behavior. Our coated samples generated using microporous synthetic zeolite pigments produced low absorption, reduced wettability and accelerated ink drying characteristics. These characteristics were caused due to the synthetic zeolite pigments, which resulted in relatively closed surface structure coated samples. The research suggested that no single selected synthetic zeolite coating performed better than the conventional fumed silica based coatings. Experimental data also showed that there was no apparent relationship between synthetic zeolite pigment pore sizes and inkjet ink absorption. For future research, above coated samples should be evaluated for pore size distribution using Mercury Porosimeter, which quantifies surface porosity of coated samples. This presented

  3. Dissolved methane concentrations in the water column and surface sediments of Hanna Shoal and Barrow Canyon, Northern Chukchi Sea

    Science.gov (United States)

    Lapham, Laura; Marshall, Kathleen; Magen, Cédric; Lyubchich, Viacheslav; Cooper, Lee W.; Grebmeier, Jacqueline M.

    2017-10-01

    Current estimates of methane (CH4) flux suggest that Arctic shelves may be a significant source of atmospheric CH4, a potent greenhouse gas. However, little information is known about the CH4 flux from most Arctic shelves, other than the East Siberian Arctic Shelf. We report here dissolved CH4 concentrations in the water column and within surface sediments of the Northern Chukchi Sea. We hypothesized that this area contains high concentrations of CH4 because it receives nutrient rich waters through the Bering Strait, promoting primary production that enhances an organic-rich material flux to the seafloor and eventual microbial methanogenesis in the sediments. In August 2012, as part of the Chukchi Sea Offshore Monitoring in Drilling Area (COMIDA) project, fourteen stations were sampled on Hanna Shoal, a shallow feature on the shelf, and ten stations across the undersea Barrow Canyon. On Hanna Shoal, water column CH4 concentrations ranged from 14 to 74 nM, and surface concentrations were up to 15 times supersaturated in CH4 compared to equilibrium with the average atmospheric concentrations (3 nM). CH4 concentrations at the sediment-water interface were around 1,500 nM, and typically increased with depth in the sediment. At the head of Barrow Canyon, water column CH4 concentrations ranged from 5 to 46 nM, with the highest concentrations in the deepest waters that were sampled (118 m). Overall, the calculated fluxes to the atmosphere ranged from 1 to 80 μmol CH4 m-2 d-1 for Hanna Shoal and 4 to 17 μmol CH4 m-2 d-1 across the Barrow Canyon stations. Although there was a large range in these fluxes, the average atmospheric flux (20 μmol CH4 m-2 d-1) across Hanna Shoal was 12 times lower than the flux reported from the East Siberian Arctic Shelf in summer. We conclude that while there is a positive flux of CH4 to the atmosphere, this part of the Chukchi Sea is not a significant source of atmospheric CH4 compared to the East Siberian Sea shelf.

  4. Development of waste-based ceramic pigments

    Directory of Open Access Journals (Sweden)

    Costa, G.

    2007-02-01

    Full Text Available We report the preparation of ceramic pigments using industrial wastes as primary sources. In this context, the use of Al-rich sludge generated in the wastewater treatment unit of an anodising or surface coating industrial plant, and a galvanizing sludge from the Cr/Ni plating process, will be detailed. The ceramic pigments reported here were prepared using typical solid state reactions involving the metal rich sludge. The main focus will be on the synthesis of chrome-tin orchid cassiterite (Sn,CrO2, chrome-tin red malayaite Ca(Cr,SnSiO5, victoria green garnet Ca3Cr2Si3O12, and chrome alumina pink/green corundum (Cr,Al2O3 pigments. The pigments were fully characterised and then were tested in a standard ceramic glaze after. Typical working conditions and colour development will be reported.

    Se presenta la preparación de pigmentos cerámicos empleando residuos industriales como fuente de materias primas. Se detallan el uso de barros ricos en aluminio obtenidos en los tratamientos de depuración de aguas de plantas industriales de anodizado y barros de galvanizados de chapados de Cr/Ni. Los pigmentos cerámicos se prepararon empleando reacción en estados sólido a partir del barro rico en metal. Los principales pigmentos estudiados son orquídea casiterita de cromo-estaño (Sn,CrO2, malayita rojo de cromo-estaño Ca(Sn,CrSiO3, granate verde victoria Ca3Cr2Si3O12, y corindón rosa/verde de cromo alúmina (Cr,Al2O3. Los pigmentos fueron caracterizados y ensayados después de ser vidriados en cerámicas estándares. Se presentan las condiciones de trabajo y el desarrollo de color.

  5. Porous Nanomaterials for Ultrabroadband Omnidirectional Anti-Reflection Surfaces with Applications in High Concentration Photovoltaics

    KAUST Repository

    Yao, Yuan

    2016-12-06

    Materials for nanoporous coatings that exploit optimized chemistries and self-assembly processes offer capabilities to reach ≈98% transmission efficiency and negligible scattering losses over the broad wavelength range of the solar spectrum from 350 nm to 1.5 μm, on both flat and curved glass substrates. These nanomaterial anti-reflection coatings also offer wide acceptance angles, up to ±40°, for both s- and p-polarization states of incident light. Carefully controlled bilayer films have allowed for the fabrication of dual-sided, gradient index profiles on plano-convex lens elements. In concentration photovoltaics platforms, the resultant enhancements in the photovoltaics efficiencies are ≈8%, as defined by experimental measurements on systems that use microscale triple-junction solar cells. These materials and their applications in technologies that require control over interface reflections have the potential for broad utility in imaging systems, photolithography, light-emitting diodes, and display technologies.

  6. Surface-Relief Gratings in Halogen-Bonded Polymer–Azobenzene Complexes: A Concentration-Dependence Study

    Directory of Open Access Journals (Sweden)

    Jelle E. Stumpel

    2017-10-01

    Full Text Available In recent years, supramolecular complexes comprising a poly(4-vinylpyridine backbone and azobenzene-based halogen bond donors have emerged as a promising class of materials for the inscription of light-induced surface-relief gratings (SRGs. The studies up to date have focused on building supramolecular hierarchies, i.e., optimizing the polymer–azobenzene noncovalent interaction for efficient surface patterning. They have been conducted using systems with relatively low azobenzene content, and little is known about the concentration dependence of SRG formation in halogen-bonded polymer–azobenzene complexes. Herein, we bridge this gap, and study the concentration dependence of SRG formation using two halogen-bond-donating azobenzene derivatives, one functionalized with a tetrafluoroiodophenyl and the other with an iodoethynylphenyl group. Both have been previously identified as efficient molecules in driving the SRG formation. We cover a broad concentration range, starting from 10 mol % azobenzene content and going all the way up to equimolar degree of complexation. The complexes are studied as spin-coated thin films, and analyzed by optical microscopy, atomic force microscopy, and optical diffraction arising during the SRG formation. We obtained diffraction efficiencies as high as 35%, and modulation depths close to 400 nm, which are significantly higher than the values previously reported for halogen-bonded polymer–azobenzene complexes.

  7. Surface-Relief Gratings in Halogen-Bonded Polymer-Azobenzene Complexes: A Concentration-Dependence Study.

    Science.gov (United States)

    Stumpel, Jelle E; Saccone, Marco; Dichiarante, Valentina; Lehtonen, Ossi; Virkki, Matti; Metrangolo, Pierangelo; Priimagi, Arri

    2017-10-28

    In recent years, supramolecular complexes comprising a poly(4-vinylpyridine) backbone and azobenzene-based halogen bond donors have emerged as a promising class of materials for the inscription of light-induced surface-relief gratings (SRGs). The studies up to date have focused on building supramolecular hierarchies, i.e., optimizing the polymer-azobenzene noncovalent interaction for efficient surface patterning. They have been conducted using systems with relatively low azobenzene content, and little is known about the concentration dependence of SRG formation in halogen-bonded polymer-azobenzene complexes. Herein, we bridge this gap, and study the concentration dependence of SRG formation using two halogen-bond-donating azobenzene derivatives, one functionalized with a tetrafluoroiodophenyl and the other with an iodoethynylphenyl group. Both have been previously identified as efficient molecules in driving the SRG formation. We cover a broad concentration range, starting from 10 mol % azobenzene content and going all the way up to equimolar degree of complexation. The complexes are studied as spin-coated thin films, and analyzed by optical microscopy, atomic force microscopy, and optical diffraction arising during the SRG formation. We obtained diffraction efficiencies as high as 35%, and modulation depths close to 400 nm, which are significantly higher than the values previously reported for halogen-bonded polymer-azobenzene complexes.

  8. Experimental study of the response functions of direct-reading instruments measuring surface-area concentration of airborne nanostructured particles

    Science.gov (United States)

    Bau, Sébastien; Witschger, Olivier; Gensdarmes, François; Thomas, Dominique

    2009-05-01

    An increasing number of experimental and theoretical studies focus on airborne nanoparticles (NP) in relation with many aspects of risk assessment to move forward our understanding of the hazards, the actual exposures in the workplace, and the limits of engineering controls and personal protective equipment with regard to NP. As a consequence, generating airborne NP with controlled properties constitutes an important challenge. In parallel, toxicological studies have been carried out, and most of them support the concept that surface-area could be a relevant metric for characterizing exposure to airborne NP [1]. To provide NP surface-area concentration measurements, some direct-reading instruments have been designed, based on attachment rate of unipolar ions to NP by diffusion. However, very few information is available concerning the performances of these instruments and the parameters that could affect their responses. In this context, our work aims at characterizing the actual available instruments providing airborne NP surface-area concentration. The instruments (a- LQ1-DC, Matter Engineering; b-AeroTrak™ 9000, TSI; c- NSAM, TSI model 3550;) are thought to be relevant for further workplace exposure characterization and monitoring. To achieve our work, an experimental facility (named CAIMAN) was specially designed, built and characterized.

  9. Experimental study of the response functions of direct-reading instruments measuring surface-area concentration of airborne nanostructured particles

    Energy Technology Data Exchange (ETDEWEB)

    Bau, Sebastien; Witschger, Olivier [Institut National de Recherche et de Securite, INRS, Laboratoire de Metrologie des Aerosols, Rue du Morvan, CS 60027, 54519 Vandoeuvre Cedex (France); Gensdarmes, Francois [Institut de Radioprotection et de Surete Nucleaire, IRSN, Laboratoire de Physique et de Metrologie des Aerosols, BP 68, 91192 Gif-sur-Yvette Cedex (France); Thomas, Dominique [Laboratoire des Sciences du Genie Chimique, LSGC/CNRS, Nancy Universite, BP 2041, 54001 Nancy Cedex (France)], E-mail: sebastien.bau@inrs.fr

    2009-05-01

    An increasing number of experimental and theoretical studies focus on airborne nanoparticles (NP) in relation with many aspects of risk assessment to move forward our understanding of the hazards, the actual exposures in the workplace, and the limits of engineering controls and personal protective equipment with regard to NP. As a consequence, generating airborne NP with controlled properties constitutes an important challenge. In parallel, toxicological studies have been carried out, and most of them support the concept that surface-area could be a relevant metric for characterizing exposure to airborne NP. To provide NP surface-area concentration measurements, some direct-reading instruments have been designed, based on attachment rate of unipolar ions to NP by diffusion. However, very few information is available concerning the performances of these instruments and the parameters that could affect their responses. In this context, our work aims at characterizing the actual available instruments providing airborne NP surface-area concentration. The instruments (a- LQ1-DC, Matter Engineering; b-AeroTrak{sup x2122} 9000, TSI; c- NSAM, TSI model 3550;) are thought to be relevant for further workplace exposure characterization and monitoring. To achieve our work, an experimental facility (named CAIMAN) was specially designed, built and characterized.

  10. Biofilm Composition and Threshold Concentration for Growth of Legionella pneumophila on Surfaces Exposed to Flowing Warm Tap Water without Disinfectant

    Science.gov (United States)

    Bakker, Geo L.; Italiaander, Ronald; Veenendaal, Harm R.; Wullings, Bart A.

    2017-01-01

    ABSTRACT Legionella pneumophila in potable water installations poses a potential health risk, but quantitative information about its replication in biofilms in relation to water quality is scarce. Therefore, biofilm formation on the surfaces of glass and chlorinated polyvinyl chloride (CPVC) in contact with tap water at 34 to 39°C was investigated under controlled hydraulic conditions in a model system inoculated with biofilm-grown L. pneumophila. The biofilm on glass (average steady-state concentration, 23 ± 9 pg ATP cm−2) exposed to treated aerobic groundwater (0.3 mg C liter−1; 1 μg assimilable organic carbon [AOC] liter−1) did not support growth of the organism, which also disappeared from the biofilm on CPVC (49 ± 9 pg ATP cm−2) after initial growth. L. pneumophila attained a level of 4.3 log CFU cm−2 in the biofilms on glass (1,055 ± 225 pg ATP cm−2) and CPVC (2,755 ± 460 pg ATP cm−2) exposed to treated anaerobic groundwater (7.9 mg C liter−1; 10 μg AOC liter−1). An elevated biofilm concentration and growth of L. pneumophila were also observed with tap water from the laboratory. The Betaproteobacteria Piscinibacter and Methyloversatilis and amoeba-resisting Alphaproteobacteria predominated in the clones and isolates retrieved from the biofilms. In the biofilms, the Legionella colony count correlated significantly with the total cell count (TCC), heterotrophic plate count, ATP concentration, and presence of Vermamoeba vermiformis. This amoeba was rarely detected at biofilm concentrations of TCC = 1 × 106 to 2 × 106 cells cm−2) was derived for growth of L. pneumophila in biofilms. IMPORTANCE Legionella pneumophila is the etiologic agent in more than 10,000 cases of Legionnaires' disease that are reported annually worldwide and in most of the drinking water-associated disease outbreaks reported in the United States. The organism proliferates in biofilms on surfaces exposed to warm water in engineered freshwater installations. An

  11. Rapid recovery of cyanobacterial pigments in desiccated biological soil crusts following addition of water.

    Directory of Open Access Journals (Sweden)

    Raeid M M Abed

    Full Text Available We examined soil surface colour change to green and hydrotaxis following addition of water to biological soil crusts using pigment extraction, hyperspectral imaging, microsensors and 13C labeling experiments coupled to matrix-assisted laser desorption and ionization time of flight-mass spectrometry (MALD-TOF MS. The topsoil colour turned green in less than 5 minutes following water addition. The concentrations of chlorophyll a (Chl a, scytonemin and echinenon rapidly increased in the top <1 mm layer while in the deeper layer, their concentrations remained low. Hyperspectral imaging showed that, in both wet and dehydrated crusts, cyanobacteria formed a layer at a depth of 0.2-0.4 mm and this layer did not move upward after wetting. 13C labeling experiments and MALDI TOF analysis showed that Chl a was already present in the desiccated crusts and de novo synthesis of this molecule started only after 2 days of wetting due to growth of cyanobacteria. Microsensor measurements showed that photosynthetic activity increased concomitantly with the increase of Chl a, and reached a maximum net rate of 92 µmol m-2 h-1 approximately 2 hours after wetting. We conclude that the colour change of soil crusts to green upon water addition was not due to hydrotaxis but rather to the quick recovery and reassembly of pigments. Cyanobacteria in crusts can maintain their photosynthetic apparatus intact even under prolonged periods of desiccation with the ability to resume their photosynthetic activities within minutes after wetting.

  12. Variability of Surface pollutants and aerosol concentration over Abu Dhabi, UAE - sources, transport and current levels

    Science.gov (United States)

    Phanikumar, Devulapalli V.; Basha, Ghouse; Ouarda, Taha B. M. J.

    2015-04-01

    In the view of recent economic, industrial, and rapid development, Abu Dhabi (24.4oN; 54.4oE; 27m msl) has become one of the most populated regions in the world despite of extreme heat, frequent dust storms, and with distinctive topography. The major sources of air pollution are from the dust and sand storms, greenhouse gas emissions, and to some extent from industrial pollution. In order to realize the accurate and comprehensive understanding of air quality and plausible sources over this region, we have made a detailed analysis of three years simultaneous measurements during 2011-13 of pollutants such as O3, SO2, NO2, CO, and PM10 concentrations. Diurnal variation of meteorological parameters such as temperature and wind speed/relative humidity clearly shows daytime maximum/minimum in summer followed by pre-monsoon, post-monsoon and winter. The prevailing winds over this region are mostly from northwesterly direction (Shamal wind). Diurnal wind pattern showed a clear contrast with the majority of the wind pattern during nighttime and early morning is from the westerly/northwesterly and daytime is from southwesterly/southeasterly directions. The diurnal pattern of O3 shows minimum during 08 LT and increases thereafter reaching maximum at 17 LT and decreases during nighttime. However, the diurnal pattern of SO2 and NO2 show a peak at ~ 08 LT and dip at ~ 14 LT during all the seasons with some variability in each season. On the other hand, the diurnal pattern of CO shows a peculiar picture of elevated levels during daytime peaking at ~ 10 LT (prominent in summer and post-monsoon) followed by a sharp decrease and minimum is ~14 LT. PM10 concentration has an early morning peak at ~ 02 LT and then decreases to a minimum value at ~11 LT and again increases in the afternoon hours (maximum at ~17 LT) depicting a forenoon-afternoon asymmetry. Monthly variation of PM10 shows maximum in pre-monsoon season and minimum in winter. Our observations show the diurnal pattern of

  13. How reliable are environmental data on 'orphan' elements? The case of bismuth concentrations in surface waters.

    Science.gov (United States)

    Filella, Montserrat

    2010-01-01

    Like all elements of the periodic table, bismuth is ubiquitously distributed throughout the environment as a result of natural processes and human activities. It is present as Bi(III) in environmental, biological and geochemical samples. Although bismuth and its compounds are considered to be non-toxic to humans, its increasing use as a replacement for lead has highlighted how little is known about its environmental and ecotoxicological behaviour. In this first critical review paper on the existing information on bismuth occurrence in natural waters, 125 papers on fresh and marine waters have been collated. Although the initial objective of this study was to establish the range of the typical concentrations of total dissolved bismuth in natural waters, this proved impossible to achieve due to the wide, and hitherto unexplained, dispersion of published data. Since analytical limitations might be one of the reasons underlying value dispersion, new analytical methods published since 2000--intended to be applied to natural waters--have also been reviewed. Disappointingly, the detection limits of the bulk of them are well above those required; they are thus of limited usefulness. Analysis of the existing information on bismuth in secondary references (i.e., books, review chapters) and on its chemical speciation in seawater revealed that the uncritical reproduction of old data is a widespread practice.

  14. Adaptive-network-based fuzzy inference system (ANFIS modelbased prediction of the surface ozone concentration

    Directory of Open Access Journals (Sweden)

    Savić Marija

    2014-01-01

    Full Text Available This paper presents the results of the tropospheric ozone concentration modeling as the dependence on volatile organic compounds - VOCs (Benzene, Toluene, m,p-Xylene, o-Xylene, Ethylbenzene; nonorganic compounds - NOx (NO, NO2, NOx, CO, H2S, SO2 and PM10 in the ambient air in parallel with the meteorological parameters: temperature, solar radiation, relative humidity, wind speed and direction. Modeling is based on measured results obtained during the year 2009. The measurements were performed at the measuring station located within an agricultural area, in vicinity of city of Zrenjanin (Serbian Banat, Serbia. Statistical analysis of obtained data, based on bivariate correlation analysis indicated that accurate modeling cannot be performed using linear statistics approach. Also, considering that almost all input variables have wide range of relative change (ratio of variance compared to range, nonlinear statistic analysis method based on only one rule describing the behavior of input variable, most certainly wouldn’t present accurate enough results. From that reason, modeling approach was based on Adaptive-Network-Based Fuzzy Inference System (ANFIS. Model obtained using ANFIS methodology resulted with high accuracy, with prediction potential of above 80%, considering that obtained determination coefficient for the final model was R2=0.802.

  15. Anticancer drugs in Portuguese surface waters - Estimation of concentrations and identification of potentially priority drugs.

    Science.gov (United States)

    Santos, Mónica S F; Franquet-Griell, Helena; Lacorte, Silvia; Madeira, Luis M; Alves, Arminda

    2017-10-01

    Anticancer drugs, used in chemotherapy, have emerged as new water contaminants due to their increasing consumption trends and poor elimination efficiency in conventional water treatment processes. As a result, anticancer drugs have been reported in surface and even drinking waters, posing the environment and human health at risk. However, the occurrence and distribution of anticancer drugs depend on the area studied and the hydrological dynamics, which determine the risk towards the environment. The main objective of the present study was to evaluate the risk of anticancer drugs in Portugal. This work includes an extensive analysis of the consumption trends of 171 anticancer drugs, sold or dispensed in Portugal between 2007 and 2015. The consumption data was processed aiming at the estimation of predicted environmental loads of anticancer drugs and 11 compounds were identified as potentially priority drugs based on an exposure-based approach (PEC b > 10 ng L -1 and/or PEC c > 1 ng L -1 ). In a national perspective, mycophenolic acid and mycophenolate mofetil are suspected to pose high risk to aquatic biota. Moderate and low risk was also associated to cyclophosphamide and bicalutamide exposition, respectively. Although no evidences of risk exist yet for the other anticancer drugs, concerns may be associated with long term effects. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. 228Ra and 228Th concentrations in GEOSECS Atlantic surface waters

    International Nuclear Information System (INIS)

    Li, Y.H.; Toggweiler, J.R.; Feely, H.W.

    1980-01-01

    An average 228 Ra flux of 0.6 +- 0.1 dpm cm -2 yr -1 from continental shelf sediments can maintain the estimated total 228 Ra inventory of about 5x10 17 dpm in Atlantic surface waters. By fitting 228 Ra and potential temperature data to Munk's vertical advection-diffusion model, upwelling rates of 17 +- 10 m yr -1 and vertical eddy diffusion coefficients of 0.4 +- 0.2 cm 2 s -1 were obtained in the upper water column of the equatorial Atlantic. The downward fluxes of particulate 228 Th across the 350-m water depth are about 0.01 to 0.04 dpm cm -2 yr -1 in the Sargasso Sea and in the regions south of 12 0 N and about 0.06 to 0.11 dpm cm -2 yr -1 in the northern temperate region (excluding the Sargasso Sea). The shorter half-removal time of 228 Th in the equatorial (10 0 S to 20 0 N) and the northern region (35 0 to 65 0 N) are related to higher biological productivity there. (author)

  17. Estimating Neural Control from Concentric vs. Eccentric Surface Electromyographic Representations during Fatiguing, Cyclic Submaximal Back Extension Exercises.

    Science.gov (United States)

    Ebenbichler, Gerold R; Unterlerchner, Lena; Habenicht, Richard; Bonato, Paolo; Kollmitzer, Josef; Mair, Patrick; Riegler, Sara; Kienbacher, Thomas

    2017-01-01

    Purpose: To investigate the differences in neural control of back muscles activated during the eccentric vs. the concentric portions of a cyclic, submaximal, fatiguing trunk extension exercise via the analysis of amplitude and time-frequency parameters derived from surface electromyographic (SEMG) data. Methods: Using back dynamometers, 87 healthy volunteers performed three maximum voluntary isometric trunk extensions (MVC's), an isometric trunk extension at 80% MVC, and 25 cyclic, dynamic trunk extensions at 50% MVC. Dynamic testing was performed with the trunk angular displacement ranging from 0° to 40° and the trunk angular velocity set at 20°/s. SEMG data was recorded bilaterally from the iliocostalis lumborum at L1, the longissimus dorsi at L2, and the multifidus muscles at L5. The initial value and slope of the root mean square (RMS-SEMG) and the instantaneous median frequency (IMDF-SEMG) estimates derived from the SEMG recorded during each exercise cycle were used to investigate the differences in MU control marking the eccentric vs. the concentric portions of the exercise. Results: During the concentric portions of the exercise, the initial RMS-SEMG values were almost twice those observed during the eccentric portions of the exercise. The RMS-SEMG values generally increased during the concentric portions of the exercise while they mostly remained unchanged during the eccentric portions of the exercise with significant differences between contraction types. Neither the initial IMDF-SEMG values nor the time-course of the IMDF-SEMG values significantly differed between the eccentric and the concentric portions of the exercise. Conclusions: The comparison of the investigated SEMG parameters revealed distinct neural control strategies during the eccentric vs. the concentric portions of the cyclic exercise. We explain these differences by relying upon the principles of orderly recruitment and common drive governing motor unit behavior.

  18. Estimating Neural Control from Concentric vs. Eccentric Surface Electromyographic Representations during Fatiguing, Cyclic Submaximal Back Extension Exercises

    Directory of Open Access Journals (Sweden)

    Gerold R. Ebenbichler

    2017-05-01

    Full Text Available Purpose: To investigate the differences in neural control of back muscles activated during the eccentric vs. the concentric portions of a cyclic, submaximal, fatiguing trunk extension exercise via the analysis of amplitude and time-frequency parameters derived from surface electromyographic (SEMG data.Methods: Using back dynamometers, 87 healthy volunteers performed three maximum voluntary isometric trunk extensions (MVC's, an isometric trunk extension at 80% MVC, and 25 cyclic, dynamic trunk extensions at 50% MVC. Dynamic testing was performed with the trunk angular displacement ranging from 0° to 40° and the trunk angular velocity set at 20°/s. SEMG data was recorded bilaterally from the iliocostalis lumborum at L1, the longissimus dorsi at L2, and the multifidus muscles at L5. The initial value and slope of the root mean square (RMS-SEMG and the instantaneous median frequency (IMDF-SEMG estimates derived from the SEMG recorded during each exercise cycle were used to investigate the differences in MU control marking the eccentric vs. the concentric portions of the exercise.Results: During the concentric portions of the exercise, the initial RMS-SEMG values were almost twice those observed during the eccentric portions of the exercise. The RMS-SEMG values generally increased during the concentric portions of the exercise while they mostly remained unchanged during the eccentric portions of the exercise with significant differences between contraction types. Neither the initial IMDF-SEMG values nor the time-course of the IMDF-SEMG values significantly differed between the eccentric and the concentric portions of the exercise.Conclusions: The comparison of the investigated SEMG parameters revealed distinct neural control strategies during the eccentric vs. the concentric portions of the cyclic exercise. We explain these differences by relying upon the principles of orderly recruitment and common drive governing motor unit behavior.

  19. [Responses of rice growth and development to elevated near-surface layer ozone (O3) concentration: a review].

    Science.gov (United States)

    Yang, Lian-xin; Wang, Yu-long; Shi, Guang-yao; Wang, Yun-xia; Zhu, Jian-guo

    2008-04-01

    Ozone (O3) is recognized as one of the most important air pollutants. At present, the worldwide average tropospheric O3 concentration has been increased from an estimated pre-industrial level of 38 nl L(-1) (25-45 nl L(-1), 8-h summer seasonal average) to approximately 50 nl L(-1) in 2000, and to 80 nl L(-1) by 2100 based on most pessimistic projections. Oryza sativa L. (rice) is the most important grain crop in the world, and thus, to correctly evaluate how the elevated near-surface layer O3 concentration will affect the growth and development of rice is of great significance. This paper reviewed the chamber (including closed and open top chamber)-based studies about the effects of atmospheric ozone enrichment on the rice visible injury symptoms, photosynthesis, water relationship, phenology, dry matter production and allocation, leaf membrane protective system, and grain yield and its components. Further research directions in this field were discussed.

  20. Variability of pesticides and nitrates concentrations along a river transect: chemical and isotopic evidence of groundwater - surface water interconnections

    Science.gov (United States)

    Baran, Nicole; Petelet-Giraud, Emmanuelle; Saplairoles, Maritxu

    2015-04-01

    Groundwater quality is increasingly monitored in Europe where various levels of nitrate and pesticide and/or metabolite contamination have been demonstrated (Loos et al., 2010, Stuart et al., 2012). The Groundwater Daughter Directive (2006/118/EC) to Water Framework Directive (WFD) particularly requires measures to prevent or limit inputs of pollutants into groundwater and compliance with good chemical status criteria (based on EU standards of nitrate and pesticides). The WFD mentioned the need to protect groundwater but also to have a particular regard to its impact and interrelationship with associated surface waters and directly dependent terrestrial Ecosystems. The Ariège river basin (SW France - 538 km²) is an alluvial plain under high agricultural pressure leading to a contamination of the aquifer by several pesticides and metabolites (Amalric et al., 2013). The Crieu is an allochtone river, crossing the plain (~ 10 km length) before joining the Ariège River. The Crieu is often dry in its middle section suggesting water leakage from surface water towards groundwater. At the opposite, the permanent flow observed downstream suggests an input of groundwater into surface water. In May 2014, while the Crieu flow was continuous through the plain, 7 river samples were collected and analyzed for pesticides, major ions, strontium concentration and isotopes. In situ measurements of electric conductivity were also performed as well as flow gauging. Two groundwaters close to the river were also sampled. The flow gauging measurements show a decreasing river discharge in the central area of the Crieu River, suggesting surface water leakage towards groundwater. Nevertheless, the electric conductivity increases along the river flow as well as some pesticides and nitrates concentrations. This chemical evolution of the river water is thus inconsistent with a simple water infiltration and another source of dissolved solutes is required to explain the increased of

  1. Characterizing the concentration of Cryptosporidium in Australian surface waters for setting health-based targets for drinking water treatment.

    Science.gov (United States)

    Petterson, S; Roser, D; Deere, D

    2015-09-01

    It is proposed that the next revision of the Australian Drinking Water Guidelines will include 'health-based targets', where the required level of potable water treatment quantitatively relates to the magnitude of source water pathogen concentrations. To quantify likely Cryptosporidium concentrations in southern Australian surface source waters, the databases for 25 metropolitan water supplies with good historical records, representing a range of catchment sizes, land use and climatic regions were mined. The distributions and uncertainty intervals for Cryptosporidium concentrations were characterized for each site. Then, treatment targets were quantified applying the framework recommended in the World Health Organization Guidelines for Drinking-Water Quality 2011. Based on total oocyst concentrations, and not factoring in genotype or physiological state information as it relates to infectivity for humans, the best estimates of the required level of treatment, expressed as log10 reduction values, ranged among the study sites from 1.4 to 6.1 log10. Challenges associated with relying on historical monitoring data for defining drinking water treatment requirements were identified. In addition, the importance of quantitative microbial risk assessment input assumptions on the quantified treatment targets was investigated, highlighting the need for selection of locally appropriate values.

  2. Oxygen 18 concentration profile measurements near the surface by 18O(p,α)15N resonance reaction

    International Nuclear Information System (INIS)

    Amsel, G.; David, D.

    1975-01-01

    The method of spectrum reduction in nuclear reaction microanalysis does not allow to obtain depth resolutions better than the order of 2000A. Resolutions of the order of 200A may be obtained by using the narrow resonance technique, when applied to thin films. The latter technique was extended to thick targets, with deep concentration profiles presenting a sharp gradient near the surface. This method is presented and illustrated by the study of 18 O profiles in oxygen diffusion measurements in growing ZrO 2 , using the 629keV resonance of the reaction 18 O(p,α) 15 N [fr

  3. Effect of different concentrations of fluoride varnish on enamel surface microhardness: An in vitro randomized controlled study

    Directory of Open Access Journals (Sweden)

    Priya Subramaniam

    2016-01-01

    Full Text Available Introduction: Dental caries occurs as a result of demineralization-remineralization phases occurring alternately at the tooth surface. Fluoride varnishes have a caries-inhibiting effect on teeth through remineralization. The resulting enamel is resistant to acid dissolution. Aim: The aim of this study is to assess enamel surface microhardness (SMH following varnish application with different fluoride concentrations. Materials and Methods: Ninety freshly extracted, caries-free premolar teeth were used. Teeth were sectioned to obtain enamel blocks from the buccal surface of crown. The blocks were serially polished and flattened, embedded in acrylic blocks and smoothened to achieve a flat surface. The samples were divided into three groups, namely, A, B, and C consisting of 30 enamel blocks each. In Group A, Fluor Protector® varnish and in Group B, Bi-Fluorid 10® varnish was applied. Group C served as controls. All samples were subjected to a demineralization-remineralization cycle for 7 days. The SMH of enamel was measured. Data obtained was subjected to statistical analysis using the Student's t-test and one-way ANOVA. Results: The mean values of enamel SMH of Groups A and B were 496.99 ± 4.81 and 449.47 ± 7.37 Vickers Hardness Number, respectively. Conclusion: Fluor Protector varnish showed significantly higher enamel SMH than that of the other two groups (P < 0.05.

  4. Corrosion behaviour and structure of the surface layer formed on austempered ductile iron in concentrated sulphuric acid

    Energy Technology Data Exchange (ETDEWEB)

    Krawiec, H. [AGH University of Science and Technology, Department of Foundry Engineering, ul. Reymonta 23, 30-059 Cracow (Poland)]. E-mail: krawiec@uci.agh.edu.pl; Stypula, B. [AGH University of Science and Technology, Department of Foundry Engineering, ul. Reymonta 23, 30-059 Cracow (Poland); Stoch, J. [Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences (PAS), ul. Niezapominajek 8, 30-239 Cracow (Poland); Mikolajczyk, M. [Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences (PAS), ul. Niezapominajek 8, 30-239 Cracow (Poland)

    2006-03-15

    The aim of this paper is to investigate the structure of the surface layer formed on austempered ductile iron (ADI) after exposure to hot concentrated sulphuric acid at the open circuit potential value (OCP). The results derived from polarization measurements carried out in sulphuric acid at a temperature of 90 deg. C show that anodic dissolution of ADI is divided into three stages (corresponding to three anodic dissolution peaks). The structure of the layer formed on alloys at 90 deg. C at OCP was investigated using X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). SEM analysis shows that the main elements of the surface layer are iron, silicon, oxygen, sulphur, and carbon. The binding energy recorded in individual bands indicates that the surface layer includes mainly SiO{sub 2} and FeOOH. The presence of sulphur at the lower oxidation state (S{sup 2-}) indicates that sulphuric acid undergoes reduction during this process. The corrosion resistance of these alloys is connected with the presence of SiO{sub 2} in the surface layer.

  5. Simulation of trace metals and PAH atmospheric pollution over Greater Paris: Concentrations and deposition on urban surfaces

    Science.gov (United States)

    Thouron, L.; Seigneur, C.; Kim, Y.; Legorgeu, C.; Roustan, Y.; Bruge, B.

    2017-10-01

    Urban areas can be subject not only to poor air quality, but also to contamination of other environmental media by air pollutants. Here, we address the potential transfer of selected air pollutants (two metals and three PAH) to urban surfaces. To that end, we simulate meteorology and air pollution from Europe to a Paris suburban neighborhood, using a four-level one-way nesting approach. The meteorological and air quality simulations use urban canopy sub-models in order to better represent the effect of the urban morphology on the air flow, atmospheric dispersion, and deposition of air pollutants to urban surfaces. This modeling approach allows us to distinguish air pollutant deposition among various urban surfaces (roofs, roads, and walls). Meteorological model performance is satisfactory, showing improved results compared to earlier simulations, although precipitation amounts are underestimated. Concentration simulation results are also satisfactory for both metals, with a fractional bias air pollutants to other environmental media. Dry deposition fluxes to various urban surfaces are mostly uniform for PAH, which are entirely present in fine particles. However, there is significantly less wall deposition compared to deposition to roofs and roads for trace metals, due to their coarse fraction. Meteorology, particle size distribution, and urban morphology are all important factors affecting air pollutant deposition. Future work should focus on the collection of data suitable to evaluate the performance of atmospheric models for both wet and dry deposition with fine spatial resolution.

  6. Simulating watercolor by modeling diffusion, pigment, and paper fibers

    Science.gov (United States)

    Small, David

    1991-08-01

    This paper explores a parallel approach to the problem of predicting the actions of pigment and water when applied to paper fibers. This work was done on the Connection Machine II, whose parallel architecture allows one to cast the problem as that of a complex cellular automata. One defines simple rules for the behavior of each cell based on the state of that cell and its immediate neighbors. By repeating the computation for each cell in the paper over many time steps, elaborate and realistic behaviors can be achieved. The simulation takes into account diffusion, surface tension, gravity, humidity, paper absorbency and the molecular weight of each pigment. At each time step a processor associated with each fiber in the paper computes water and pigment gradients, surface tension and gravitational forces, and decides if there should be any movement of material. Pigment and water can be applied and removed (blotting) with masks created from type or scanned images. Use of a parallel processor simplifies the creation and testing of software, and variables can be stored and manipulated at highprecision. The resulting simulation runs at approximately one-tenth real time.

  7. Heat-Resistant Ceramic Pigments on the Base of Waste Vanadium Catalyst and Alumina

    Directory of Open Access Journals (Sweden)

    M. B. Sedelnikova

    2013-01-01

    Full Text Available Ceramic pigments on the base of technogenic silica-containing material—waste vanadium catalyst were obtained in this work. Corundum is identified along with the predominant mullite phase in the composition of pigments. The ions of nickel, chromium, and iron are embedded in the structure if the concentration of the corresponding oxide in the initial mixture does not exceed 10 wt.%. In this case, the oxide is not identified in a free form according to the results of X-ray diffraction analysis. Spinel CoAl2O4 is formed in cobalt pigments. The developed pigments keep the firing temperature up to 1200°C. The obtained pigments may be recommended for ceramic paints and colored glazes for building materials.

  8. Water‐soluble red pigments from Isaria farinosa and structural characterization of the main colored component

    DEFF Research Database (Denmark)

    Velmurugan, Palanivel; Lee, Yong Hoon; Nanthakumar, Kuppanan

    2010-01-01

    The present study describes the red pigment synthesized by the filamentous fungi Isaria farinosa under submerged culture conditions. The pigment production was optimal under the following conditions: pH 5, agitation speed 150 rpm, temperature 27 °C, incubation time 192 h, light source total...... darkness, sucrose and glucose as carbon source, yeast extract, meat peptone and monosodium glutamate at a fixed concentration of 3% as nitrogen source. The addition of 10 mM CaCl2 to the culture medium increased the biomass and pigment production. Structural elucidation of the pigment using gas...... commercial importance in the production of Isaria farinosa pigment for industrial application after considerable toxicological examination. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)...

  9. Ag nanoparticles agargel nanocomposites for SERS detection of cultural heritage interest pigments

    Science.gov (United States)

    Amato, F.; Micciche', C.; Cannas, M.; Gelardi, F. M.; Pignataro, B.; Li Vigni, M.; Agnello, S.

    2018-02-01

    Agarose gel (agargel) composites with commercial and laboratory made silver nanoparticles were prepared by a wet solution method at room temperature. The gel composites were used for pigment extraction and detection by Raman spectroscopy. Red (alizarin) and violet (crystal violet) pigments deposited on paper were extracted by the composites and were investigated by micro-Raman spectroscopy. Evaluation was carried out of the surface-enhanced Raman spectroscopy (SERS) effect induced by the silver nanoparticles embedded in the gel. A kinetic approach as a function of time was used to determine the efficiency of pigments extraction by composites deposition. A non-invasive extraction process of few minutes is demonstrated. This process induces active SERS for both used pigments. The reported results show the full exploitability of agargel silver nanoparticle composites for the extraction of pigments from paper based artworks.

  10. Oral melanin pigmentation in 467 Thai and Malaysian people with special emphasis on smoker's melanosis.

    Science.gov (United States)

    Hedin, C A; Axéll, T

    1991-01-01

    At the faculties of dentistry in Chiang Mai, Thailand (CM), and Kuala Lumpur, Malaysia (KL), 234 and 233 consecutive out-patients were interviewed concerning tobacco and chewing habits and examined for the presence of oral melanin pigmentation. Tobacco was regularly used by 32% and 28% of the studied populations in CM and KL. Cigarette smoking was the predominant habit, but the chewing of betel and tea leaves (miang) and the smoking of banana leaf cigars (khi yo) was also registered. The genetically acquired pigmentation dominated. Although nearly all non-tobacco users in the Malay and Indian populations had oral melanin pigmentation, it was found that tobacco smokers had significantly more oral surfaces pigmented than non-tobacco users. Among Thais, the percentage of pigmented individuals was significantly higher among tobacco smokers. It was concluded that tobacco smoking stimulates oral melanocytes to a higher melanin production also in dark-skinned ethnic groups.

  11. Impacts of early autumn Arctic sea ice concentration on subsequent spring Eurasian surface air temperature variations

    Science.gov (United States)

    Chen, Shangfeng; Wu, Renguang

    2017-11-01

    This study reveals a close relation between autumn Arctic sea ice change (SIC) in the Laptev Sea-eastern Siberian Sea-Beaufort Sea and subsequent spring Eurasian surface air temperature (SAT) variation. Specifically, more (less) SIC over the above regions in early autumn generally correspond to SAT warming (cooling) over the mid-high latitudes of Eurasia during subsequent spring. Early autumn Arctic SIC affects spring Eurasian SAT via modulating spring Arctic Oscillation (AO) associated atmospheric changes. The meridional temperature gradient over the mid-high latitudes decreases following the Arctic sea ice loss. This results in deceleration of prevailing westerly winds over the mid-latitudes of the troposphere, which leads to increase in the upward propagation of planetary waves and associated Eliassen-Palm flux convergence in the stratosphere over the mid-high latitudes. Thereby, westerly winds in the stratosphere are reduced and the polar vortex is weakened. Through the wave-mean flow interaction and downward propagation of zonal wind anomalies, a negative spring AO pattern is formed in the troposphere, which favors SAT cooling over Eurasia. The observed autumn Arctic SIC-spring Eurasian SAT connection is reproduced in the historical simulation (1850-2005) of the flexible global ocean-atmosphere-land system model, spectral version 2 (FGOALS-s2). The FGOALS-s2 also simulates the close connection between autumn SIC and subsequent spring AO. Further analysis suggests that the prediction skill of the spring Eurasian SAT was enhanced when taking the autumn Arctic SIC signal into account.

  12. Core and surface microgel mechanics are differentially sensitive to alternative crosslinking concentrations.

    Science.gov (United States)

    Mohapatra, Himansu; Kruger, Terra M; Lansakara, Thiranjeewa I; Tivanski, Alexei V; Stevens, Lewis L

    2017-08-30

    Microgel mechanics are central to the swelling of stimuli-responsive materials and furthermore have recently emerged as a novel design space for tuning the uptake of nanotherapeutics. Despite this importance, the techniques available to assess mechanics, at the sub-micron scale, remain limited. In this report, all mechanical moduli for a series of air-dried, polystyrene-co-poly(N-isopropylacrylamide) (pS-co-NIPAM) microgels of varying composition in monomer and crosslinker (N,N'-methylene-bisacrylamide (BIS)) mol% have been determined using Brillouin light scattering (BLS) and AFM nanoindentation. These techniques sample the material through distinct means and provide complementary nanomechanical data. An initial demonstration of this combined approach is used to evaluate size-dependent nanomechanics in pS particles of varying diameter. For the pS-co-NIPAM series, our BLS results demonstrate an increase in Young's (E) and shear moduli with increasing NIPAM and/or BIS mol%, while the Poisson's ratio decreased. The same rank order in E was observed from AFM and the two techniques correlate well. However, at low BIS crosslinking, an inverted particle structure persists and small increases in BIS yield a higher increase in E from AFM relative to BLS, consistent with a higher density at the particle surface. At higher BIS incorporation, the microgel reverts to a typical, dense-core structure and further increasing BIS yields changes to core-particle mechanics reflected in BLS. Lastly, at 75 mol% NIPAM, the microgels displayed a broad volume phase transition and increased crosslinking resulted in a minor, yet unexpected, increase in swelling ratio. This complementary approach offers new insight into nanomechanics critical for microgel design and application.

  13. Availability and Utilization of Pigments from Microalgae.

    Science.gov (United States)

    Begum, Hasina; Yusoff, Fatimah Md; Banerjee, Sanjoy; Khatoon, Helena; Shariff, Mohamed

    2016-10-02

    Microalgae are the major photosynthesizers on earth and produce important pigments that include chlorophyll a, b and c, β-carotene, astaxanthin, xanthophylls, and phycobiliproteins. Presently, synthetic colorants are used in food, cosmetic, nutraceutical, and pharmaceutical industries. However, due to problems associated with the harmful effects of synthetic colorants, exploitation of microalgal pigments as a source of natural colors becomes an attractive option. There are various factors such as nutrient availability, salinity, pH, temperature, light wavelength, and light intensity that affect pigment production in microalgae. This paper reviews the availability and characteristics of microalgal pigments, factors affecting pigment production, and the application of pigments produced from microalgae. The potential of microalgal pigments as a source of natural colors is enormous as an alternative to synthetic coloring agents, which has limited applications due to regulatory practice for health reasons.

  14. Pigment chromatic adaptation in Cyclotella caspia Grunow (Bacillariophyta

    Directory of Open Access Journals (Sweden)

    Donato Seiji Abe

    1991-01-01

    Full Text Available The diatom Cyclotella caspia Grunow, isolated from surface waters of the Ubatuba region (São Paulo State, Brazil was submitted to different light spectral distributions for examination of its adaptative response. Growth rate and the photosynthetic pigments chlorophyll a, chlorophyll c, carotenoids and phaeopigments were measured under white, blue and red light of the same intensity (8 and 20 µE.cm-2.s-1. Growth rate increased under blue light while red light increased chl a concentration. The relative proportion of chl a and carotenoids did not change, demonstrating the absence of complementary chromatic adaptation.A diatomácea Cyclotella caspia Grunow, isolada de águas superficiais da região de Ubatuba (Estado de São Paulo, Brasil, foi submetida a diferentes intervalos espectrais de luz com a finalidade de se examinar sua resposta adaptativa. Foram medidos a taxa de crescimento e os pigmentos fotossintéticos clorofila a, clorofila c, carotenóides e feopigmentos, sob luz branca, azul e vermelha de mesmas intensidades (8 e 20 µE.cm-2.s-1. A taxa de crescimento aumentou sob luz azul, sendo que a concentração de clorofila a aumentar sob luz vermelha. A proporção relativa de clα e carotenóides não variou, demonstrando a ausência de adapatação cromática complementar.

  15. Control of Surface Mounted Permanent Magnet Motors with Special Application to Fractional-Slot Concentrated Windings

    Energy Technology Data Exchange (ETDEWEB)

    Lawler, J.S.

    2005-12-21

    It is well known that the ability of the permanent magnet synchronous machine (PMSM) to operate over a wide constant power speed range (CPSR) is dependent upon the machine inductance [1,2,3,4,5]. Early approaches for extending CPSR operation included adding supplementary inductance in series with the motor [1] and the use of anti-parallel thyristor pairs in series with the motor-phase windings [5]. The increased inductance method is compatible with a voltage-source inverter (VSI) controlled by pulse-width modulation (PWM) which is called the conventional phase advance (CPA) method. The thyristor method has been called the dual mode inverter control (DMIC). Neither of these techniques has met with wide acceptance since they both add cost to the drive system and have not been shown to have an attractive cost/benefit ratio. Recently a method has been developed to use fractional-slot concentrated windings to significantly increase the machine inductance [6]. This latest approach has the potential to make the PMSM compatible with CPA without supplemental external inductance. If the performance of such drive is acceptable, then the method may make the PMSM an attractive option for traction applications requiring a wide CPSR. A 30 pole, 6 kW, 6000 maximum revolutions per minute (rpm) prototype of the fractional-slot PMSM design has been developed [7]. This machine has significantly more inductance than is typical of regular PMSMs. The prototype is to be delivered in late 2005 to the Oak Ridge National Laboratory (ORNL) for testing and development of a suitable controller. In advance of the test/control development effort, ORNL has used the PMSM models developed over a number of previous studies to study the steady-state performance of high-inductance PMSM machines with a view towards control issues. The detailed steady-state model developed includes all motor and inverter-loss mechanisms and will be useful in assessing the performance of the dynamic controller to be

  16. Quantitative analysis of pigment dispersion taking into account the full agglomerate size distribution

    DEFF Research Database (Denmark)

    Kiil, Søren

    This work concerns the development of simulation tools for mapping of pigment dispersion. Focus has been on the mechanical breakage of pigment agglomerates. The underlying physical mechanism was assumed to be surface erosion of spherical pigment agglomerates, and the full agglomerate particle size...... distribution was simulated. Data from previous experimental investigations with organic pigments were used for model validation.When the linear rate of agglomerate surface erosion was taken to be proportional to the external agglomerate surface area, simulations of the volume-moment mean diameter over time...... were in good quantitative agreement with experimental data. The only adjustable parameter used was an apparent rate constant for the linear agglomerate erosion rate. Model simulations, at selected values of time, for the full agglomerate particle size distribution were in good qualitative agreement...

  17. Mathematical modeling of pigment dispersion taking into account the full agglomerate particle size distribution

    DEFF Research Database (Denmark)

    Kiil, Søren

    2017-01-01

    The purpose of this work is to develop a mathematical model that can quantify the dispersion of pigments, with a focus on the mechanical breakage of pigment agglomerates. The underlying physical mechanism was assumed to be surface erosion of spherical pigment agglomerates. The full agglomerate......-based acrylic vehicle in a three-roll mill. When the linear rate of agglomerate surface erosion was taken to be proportional to the external agglomerate surface area, simulations of the volume-moment mean diameter over time were in good quantitative agreement with experimental data for all three pigments....... The only adjustable parameter used was an apparent rate constant for the linear agglomerate erosion rate. Model simulations, at selected values of time, for the full agglomerate particle size distribution were in good qualitative agreement with the measured values. A quantitative match of the experimental...

  18. Enhanced production of pigments by addition of surfactants in submerged fermentation of Monascus purpureus H1102.

    Science.gov (United States)

    Wang, Yonghui; Zhang, Bobo; Lu, Liping; Huang, Yan; Xu, Ganrong

    2013-10-01

    The production of pigments by Monascus spp. has attracted increasing attention. Modification of the cell membrane structure by addition of surfactants has proved to be effective for the secretion of intracellular metabolites. Hence in this study the effects and underlying mechanism of surfactants on the production of pigments in submerged fermentation of Monascus purpureus H1102 were systematically investigated. Various surfactants exerted significant but different impacts on the biomass and production of pigments. The maximum production of pigment (304.3 U mL(-1) ) and highest extracellular/intracellular pigment ratio (1.46) were achieved when 15 g L(-1) Triton X-100 was added at 24 h of fermentation, corresponding to significant increases of 88.4 and 240% respectively compared with the control. Meanwhile, the concentration of citrinin (0.94 mg L(-1) ) was 20.6% lower than that of the control. A further study on the fatty acid composition of M. purpureus H1102 showed that the unsaturated/saturated fatty acid ratio and the index of unsaturated fatty acid increased significantly with the addition of Triton X-100. The addition of surfactant Triton X-100 could greatly enhance the production of pigment. It was suggested that Triton X-100 facilitated the secretion of intracellular pigment and therefore enhanced pigment production accordingly. © 2013 Society of Chemical Industry.

  19. Sensitive and selective analysis of a wide concentration range of IGFBP7 using a surface plasmon resonance biosensor.

    Science.gov (United States)

    Jang, Dae-Ho; Choi, Youngbo; Choi, Yong-Soo; Kim, Sun-Mi; Kwak, Hojung; Shin, Se-Hyun; Hong, Surin

    2014-11-01

    A sensitive method for selectively detecting insulin-like growth factor-binding protein 7 (IGFBP7) over a wide range of concentrations based on the surface plasmon resonance (SPR) biosensing techniques is described. IGFBP7 has been shown to regulate cell proliferation, cell adhesion, cellular senescence, apoptosis, and angiogenesis in several different cancer cell lines. Since the concentration of IGFBP7 can vary widely in the body, determining the precise concentration of IGFBP7 over a wide range of concentrations is important, since it serves as an inducible biomarker for both disease diagnosis and subsequent therapy. The SPR sensing method is based on the selective interaction of IGFBP7 with specific anti-IGFBP7 proteins on a gold thin film, which was covalently bound to the Fc-binding domain of protein G on a mixed self-assembled monolayer composed of DSNHS (S2(CH2)11COO(CH2)2COO-(N-hydroxysuccinimide)) and mercaptoundecanol, and effect of this on changes in the SPR profiles. The limit of detection (LOD) of the SPR biosensor was determined to be 10 ng/ml, which is a reasonable LOD value for biomedical applications. The response is essentially linear in the concentration range of 10-300 ng/ml. The SPR biosensor also shows specificity for IGFBP7 compared to that for biologically relevant interleukin (IL) derivatives including IL4, IL23, IL29, and IFG1. These molecules are also present along with IGFBP7 in the cell culture medium and have the potential to interfere with the analysis. Finally, the level secretion of IGFBP7 from cancer cells detected by the SPR biosensor showed a good correlation with a commercial kit using an IGFBP7 enzyme-linked immunosorbent assay. The findings reported herein indicate that the SPR biosensor for IGFBP7 would be applicable in a wide variety of biomedical fields. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Effect of Fe3O4 Magnetic Nanoparticle Concentration on the Signal of Surface Plasmon Resonance (SPR) Spectroscopy

    Science.gov (United States)

    Oktivina, M.; Nurrohman, D. T.; Rinto, A. N. Q. Z.; Suharyadi, E.; Abraha, K.

    2017-05-01

    Effect of Fe3O4 magnetic nanoparticle concentration on the signal of surface plasmon resonance (SPR) spectra has been successfully observed. The Fe3O4 nanoparticles with a particle size of about 10.5 ± 0.2 nm were used as active materials to increase the SPR response. X-ray diffraction (XRD) pattern showed that Fe3O4 nanoparticles have a high degree of crystallinity with spinel structure. The SPR system was successfully set up by using a glass prism coupler in a Kretschmann configuration in which gold (Au) thin film was thermally evaporated on the prism base. A green laser of wavelength 543 nm was used as light source. The angular scan in the attenuated total reflection (ATR) spectra showed a dropping intensity. Those things clearly indicated the appearance of SPR coupling phenomenon on the interface of Au thin film. The SPR spectra of fixed Au masses were also performed with same angular positions of dips. The Fe3O4 nanoparticles were deposited on gold thin film as a third layer which was synthesized via co-precipitation method. Hence, it was observed that the variation of Fe3O4 concentration affected the SPR spectra profile. The concentrations of Fe3O4 nanoparticles are 1, 3, 5, 7, 9, and 11 mg/ml which correspond to the angle shift of 0.1°, 0.3°, 0.5°, 0.7°, 0.9°, and 1.0°, respectively. The SPR angle of the dip was shifted to higher value due to change of refractive index of the medium as Fe3O4 nanoparticles concentration increases. Based on this result, we can conclude that the angle shift of SPR increases with increasing concentration of Fe3O4 nanoparticles.

  1. Concentrations and sources of polycyclic aromatic hydrocarbons in surface coastal sediments of the northern Gulf of Mexico

    Science.gov (United States)

    2014-01-01

    Background Coastal sediments in the northern Gulf of Mexico have a high potential of being contaminated by petroleum hydrocarbons, such as polycyclic aromatic hydrocarbons (PAHs), due to extensive petroleum exploration and transportation activities. In this study we evaluated the spatial distribution and contamination sources of PAHs, as well as the bioavailable fraction in the bulk PAH pool, in surface marsh and shelf sediments (top 5 cm) of the northern Gulf of Mexico. Results PAH concentrations in this region ranged from 100 to 856 ng g−1, with the highest concentrations in Mississippi River mouth sediments followed by marsh sediments and then the lowest concentrations in shelf sediments. The PAH concentrations correlated positively with atomic C/N ratios of sedimentary organic matter (OM), suggesting that terrestrial OM preferentially sorbs PAHs relative to marine OM. PAHs with 2 rings were more abundant than those with 5–6 rings in continental shelf sediments, while the opposite was found in marsh sediments. This distribution pattern suggests different contamination sources between shelf and marsh sediments. Based on diagnostic ratios of PAH isomers and principal component analysis, shelf sediment PAHs were petrogenic and those from marsh sediments were pyrogenic. The proportions of bioavailable PAHs in total PAHs were low, ranging from 0.02% to 0.06%, with higher fractions found in marsh than shelf sediments. Conclusion PAH distribution and composition differences between marsh and shelf sediments were influenced by grain size, contamination sources, and the types of organic matter associated with PAHs. Concentrations of PAHs in the study area were below effects low-range, suggesting a low risk to organisms and limited transfer of PAHs into food web. From the source analysis, PAHs in shelf sediments mainly originated from direct petroleum contamination, while those in marsh sediments were from combustion of fossil fuels. PMID:24641695

  2. Defining an Abrasion Index for Lunar Surface Systems as a Function of Dust Interaction Modes and Variable Concentration Zones

    Science.gov (United States)

    Kobrick, Ryan L.; Klaus, David M.; Street, Kenneth W., Jr.

    2010-01-01

    Unexpected issues were encountered during the Apollo era of lunar exploration due to detrimental abrasion of materials upon exposure to the fine-grained, irregular shaped dust on the surface of the Moon. For critical design features involving contact with the lunar surface and for astronaut safety concerns, operational concepts and dust tolerance must be considered in the early phases of mission planning. To systematically define material selection criteria, dust interaction can be characterized by two-body or three-body abrasion testing, and subcategorically by physical interactions of compression, rolling, sliding and bending representing specific applications within the system. Two-body abrasion occurs when a single particle or asperity slides across a given surface removing or displacing material. Three-body abrasion occurs when multiple particles interact with a solid surface, or in between two surfaces, allowing the abrasives to freely rotate and interact with the material(s), leading to removal or displacement of mass. Different modes of interaction are described in this paper along with corresponding types of tests that can be utilized to evaluate each configuration. In addition to differential modes of abrasion, variable concentrations of dust in different zones can also be considered for a given system design and operational protocol. These zones include: (1) outside the habitat where extensive dust exposure occurs, (2) in a transitional zone such as an airlock or suitport, and (3) inside the habitat or spacesuit with a low particle count. These zones can be used to help define dust interaction frequencies, and corresponding risks to the systems and/or crew can be addressed by appropriate mitigation strategies. An abrasion index is introduced that includes the level of risk, R, the hardness of the mineralogy, H, the severity of the abrasion mode, S, and the frequency of particle interactions, F.

  3. Asian industrial lead inputs to the North Pacific evidenced by lead concentrations and isotopic compositions in surface waters and aerosols.

    Science.gov (United States)

    Gallon, Céline; Ranville, Mara A; Conaway, Christopher H; Landing, William M; Buck, Clifton S; Morton, Peter L; Flegal, A Russell

    2011-12-01

    Recent trends of atmospheric lead deposition to the North Pacific were investigated with analyses of lead in aerosols and surface waters collected on the fourth Intergovernmental Oceanographic Commission Contaminant Baseline Survey from May to June, 2002. Lead concentrations of the aerosols varied by 2 orders of magnitude (0.1-26.4 pmol/m(3)) due in part to variations in dust deposition during the cruise. The ranges in lead aerosol enrichment factors relative to iron (1-119) and aluminum (3-168) were similar, evidencing the transport of Asian industrial lead aerosols across the North Pacific. The oceanic deposition of some of those aerosols was substantiated by the gradient of lead concentrations of North Pacific waters, which varied 3-fold (32.7-103.5 pmol/kg), were highest along with the Asian margin of the basin, and decreased eastward. The hypothesized predominance of Asian industrial lead inputs to the North Pacific was further corroborated by the lead isotopic composition of ocean surface waters ((206)Pb/(207)Pb = 1.157-1.169; (208)Pb/(206)Pb = 2.093-2.118), which fell within the range of isotopic ratios reported in Asian aerosols that are primarily attributed to Chinese industrial lead emissions.

  4. Isolation and molecular identification of a UV-resistant strain of Dietzia maris and antioxidant activity of pigment

    Directory of Open Access Journals (Sweden)

    Narges Zamanian

    2016-09-01

    Full Text Available Introduction: The ability of radioresistant bacteria to survive high levels of UV radiation has been linked to their strong DNA repair systems and ability to produce primary and secondary metabolic products. The biosynthesis of pigments provides an opportunity for bacteria to live in radiation-rich environment. Recent radiation-responsive pigments are used commercially as food colorants, anticancer drugs, as well as antibiotics and for cosmetic purposes. Materials and methods: Soil sample of Omidiyeh city was collected during the spring of 2014 and UV-resistant strain was isolated after primary and secondary screening. Then it was identified by molecular methods (16S rRNA gene sequencing. Antioxidant activity of pigment was evaluated by 2,2 -diphenyl-1-picryl hydrazyl (DPPH and the reducing power of pigments were analyzed by ferric chloride. Results: In this present study, new UV-resistant strain NM2 was isolated and by comparison of these 16S rRNA gene sequences to public database using the BLAST, the genus and species of the isolate was identified as Dietzia maris with 99% similarity. Extraction of pigment from isolated strain was carried out by methanol and acetone as solvents. The spectrum is characterized by maximum peak at 473 nm for pigment of NM2 strain. Antioxidant activity and the reducing ability of pigments increased by increasing their concentrations. NM2 strain pigment showed EC50 concentration of 3.30 mg/ml for DPPH free radical scavenging activity, and EC50 concentration of 28.46 µg/ml for reducing power. Discussion and conclusion: Isolation of natural resources of pigment is very important with high anti-oxidant activity. In the current study, pigment of UV-resistant bacteria demonstrated a strong antioxidant activity in vitro and pigment of these bacteria could play an important role in UV tolerance. Pigment of UV-resistant bacteria may be an appropriate source for antioxidative-related functional foods and the pharmaceutical

  5. A summary of the scientific literature on the effects of fire on the concentration of nutrients in surface waters

    Science.gov (United States)

    Ranalli, Anthony J.

    2004-01-01

    This paper provides a detailed review of the chemical changes that occur in soil during a fire, the pathways by which nutrients are transferred from soil to surface-water bodies following a fire, and the temporal and spatial effects of fires on the concentration of nutrients in surface-water bodies during and following a fire that have been reported in the scientific literature. Thirty-nine papers from the scientific literature that represent studies that (1) were done in a variety of environments (savannas, grasslands, temperate forests, alpine forests, and so forth); (2) had a range of sampling frequency and duration, such as during and immediately following a fire (from the start of fire to 1 year later), short-term sampling (from end of fire to 3 years later), and long term-sampling (sampling for greater than 3 years following a fire); and (3) incorporated watersheds with various burn intensities, severities, and histories were reviewed and summarized. The review of the scientific literature has revealed that measurable effects of fires on streamwater quality are most likely to occur if the fire was severe enough to burn large amounts of organic matter, if windy conditions were present during the fire, if heavy rain occurred following the fire, and if the fire occurred in a watershed with steep slopes and soils with little cation-exchange capacity. Measurable effects of fires on lake- and reservoir-water quality are most likely to occur if, in addition to the factors listed for streams, the lake or reservoir is oligotrophic or mesotrophic and the residence time of water in the lake or reservoir is short relative to the length of time elevated concentrations of nutrients occur in runoff. Knowledge of whether a lake or reservoir is nitrogen or phosphorus limited is important because eutrophication of nitrogen-limited lakes may occur following a fire due to increasing nitrogen:phosphorus ratios caused by prolonged increases of nitrogen concentrations, especially

  6. Non-monotonic swelling of surface grafted hydrogels induced by pH and/or salt concentration

    Science.gov (United States)

    Longo, Gabriel S.; Olvera de la Cruz, Monica; Szleifer, I.

    2014-09-01

    We use a molecular theory to study the thermodynamics of a weak-polyacid hydrogel film that is chemically grafted to a solid surface. We investigate the response of the material to changes in the pH and salt concentration of the buffer solution. Our results show that the pH-triggered swelling of the hydrogel film has a non-monotonic dependence on the acidity of the bath solution. At most salt concentrations, the thickness of the hydrogel film presents a maximum when the pH of the solution is increased from acidic values. The quantitative details of such swelling behavior, which is not observed when the film is physically deposited on the surface, depend on the molecular architecture of the polymer network. This swelling-deswelling transition is the consequence of the complex interplay between the chemical free energy (acid-base equilibrium), the electrostatic repulsions between charged monomers, which are both modulated by the absorption of ions, and the ability of the polymer network to regulate charge and control its volume (molecular organization). In the absence of such competition, for example, for high salt concentrations, the film swells monotonically with increasing pH. A deswelling-swelling transition is similarly predicted as a function of the salt concentration at intermediate pH values. This reentrant behavior, which is due to the coupling between charge regulation and the two opposing effects triggered by salt concentration (screening electrostatic interactions and charging/discharging the acid groups), is similar to that found in end-grafted weak polyelectrolyte layers. Understanding how to control the response of the material to different stimuli, in terms of its molecular structure and local chemical composition, can help the targeted design of applications with extended functionality. We describe the response of the material to an applied pressure and an electric potential. We present profiles that outline the local chemical composition of the

  7. Biofilm Composition and Threshold Concentration for Growth of Legionella pneumophila on Surfaces Exposed to Flowing Warm Tap Water without Disinfectant.

    Science.gov (United States)

    van der Kooij, Dick; Bakker, Geo L; Italiaander, Ronald; Veenendaal, Harm R; Wullings, Bart A

    2017-03-01

    Legionella pneumophila in potable water installations poses a potential health risk, but quantitative information about its replication in biofilms in relation to water quality is scarce. Therefore, biofilm formation on the surfaces of glass and chlorinated polyvinyl chloride (CPVC) in contact with tap water at 34 to 39°C was investigated under controlled hydraulic conditions in a model system inoculated with biofilm-grown L. pneumophila The biofilm on glass (average steady-state concentration, 23 ± 9 pg ATP cm -2 ) exposed to treated aerobic groundwater (0.3 mg C liter -1 ; 1 μg assimilable organic carbon [AOC] liter -1 ) did not support growth of the organism, which also disappeared from the biofilm on CPVC (49 ± 9 pg ATP cm -2 ) after initial growth. L. pneumophila attained a level of 4.3 log CFU cm -2 in the biofilms on glass (1,055 ± 225 pg ATP cm -2 ) and CPVC (2,755 ± 460 pg ATP cm -2 ) exposed to treated anaerobic groundwater (7.9 mg C liter -1 ; 10 μg AOC liter -1 ). An elevated biofilm concentration and growth of L. pneumophila were also observed with tap water from the laboratory. The Betaproteobacteria Piscinibacter and Methyloversatilis and amoeba-resisting Alphaproteobacteria predominated in the clones and isolates retrieved from the biofilms. In the biofilms, the Legionella colony count correlated significantly with the total cell count (TCC), heterotrophic plate count, ATP concentration, and presence of Vermamoeba vermiformis This amoeba was rarely detected at biofilm concentrations of <100 pg ATP cm -2 A threshold concentration of approximately 50 pg ATP cm -2 (TCC = 1 × 10 6 to 2 × 10 6 cells cm -2 ) was derived for growth of L. pneumophila in biofilms. IMPORTANCE Legionella pneumophila is the etiologic agent in more than 10,000 cases of Legionnaires' disease that are reported annually worldwide and in most of the drinking water-associated disease outbreaks reported in the United States. The organism proliferates in biofilms on surfaces

  8. Ecological-friendly pigments from fungi.

    Science.gov (United States)

    Durán, Nelson; Teixeira, Maria F S; De Conti, Roseli; Esposito, Elisa

    2002-01-01

    The dyestuff industry is suffering from the increases in costs of feedstock and energy for dye synthesis, and they are under increasing pressure to minimize the damage to the environment. The industries are continuously looking for cheaper, more environmentally friendly routes to existing dyes. The aim of this minireview is to discuss the most important advances in the fungal pigment area and its interest in biotechnological applications. Characteristic pigments are produced by a wide variety of fungi and the chemical composition of natural dyes are described. These pigments exhibit several biological activities besides cytotoxicity. The synthetic pigments authorized by the EC and in USA and the natural pigments available in the world market are discussed. The obstacle to the exploitation of new natural pigments sources is the food legislation, requesting costly toxicological research, manufacturing costs, and acceptance by consumers. The dislike for novel ingredients is likely to be the biggest impediment for expansion of the pigment list in the near future. If the necessary toxicological testing and the comparison with accepted pigments are made, the fungal pigments, could be acceptable by the current consumer. The potentiality of pigment production in Brazil is possible due to tremendous Amazonian region biodiversity.

  9. Effectiveness of cysteine proteases on protein/pigment film removal.

    Science.gov (United States)

    Yao, Jiang-Wu; Xiao, Yin; Zuo, Qi-liang; Zhang, Yi; Tao, Tao; Lin, Chang-Jian

    2013-11-01

    Theaflavin (TF) from the black tea can react to human salivary proline-rich proteins (PRPs) to form stains on exposed dental surfaces. Here, we employed a model of protein/pigment film using TF and dephosphorylated bovine β-casein (Dβ-CN), which has an extended conformation, similar to that of salivary PRPs, on a sensor surface to assess the efficacy of cysteine proteases (CPs) including papain, stem bromelain, and ficin, on removing TF bound to Dβ-CN and the control TF readsorption on the residual substrate surfaces was also measured. The protein/pigment complex film was built by using a quartz crystal microbalance with dissipation (QCM-D). The efficacies of CPs were assessed by Boltzman equation model. The surface details were detected by grazing angle infrared spectroscopy spectra, atomic force microscopy images, and contact angles. The efficacy order of CPs on hydrolyzing protein/pigment complex film is ficin>papain>bromelain. The results from grazing angle infrared spectroscopy spectra, atomic force microscopy images, and contact angles demonstrated that TF bound on the Dβ-CN was effectively removed by the CPs, and the amount of TF readsorption on both the residual film of the Dβ-CN/TF and the Dβ-CN was markedly decreased after hydrolysis. This study indicates the potential application of the CPs for tooth stain removal and suggests that these enzymes are worthy of further investigation for use in oral healthcare. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Barium concentrations and speciation in surface waters collected from an active barium mining area in Guizhou Province, southwestern China.

    Science.gov (United States)

    Lu, Qinhui; Xu, Xiaohang; Xu, Zhidong; Liang, Longchao; Shang, Lihai; Xiao, Dean; Zhang, Sensen; Jiang, Yuping; Qiu, Guangle

    2018-03-01

    Barium (Ba) is a toxic element and can cause serious health effects. Humans have experienced increased exposure to Ba due to its intensive usage in industrial areas and daily life. Anthropogenic activities of Ba mining and the manufacture of Ba containing products introduce the element into surrounding areas, posing environmental concerns. Concentrations of total Ba (TBa) and dissolved Ba (DBa) in water samples collected from active Ba mines in Tianzhu, east Guizhou Province, southwestern China were measured to show the regional dispersion of Ba contamination. Aqueous Ba species in water were calculated using the PHREEQC program. The results showed that TBa and DBa concentrations ranged from 6.7 to 483.1 μg/L and from 7.5 to 222.7 μg/L, respectively. TBa concentrations presented a high average value of 126.6 μg/L and greatly exceeded the reported common value of 10 μg/L Ba in surface water set by the Ministry of Environment Protection of China. PHREEQC results indicated that Ba species in water were present as Ba 2+ , BaSO 4 , BaHCO 3 , BaCO 3 , and BaOH + . The distribution of Ba species in water is controlled by pH and total organic carbon (TOC), and the lower pH (pH < 7) the higher the dissolved fractions. The log K d values (K d , dissolved-particulate distribution coefficients) varied from 2.41 to 6.32. Significant correlations were observed among Ba 2+ and K + , Na + , Cl - , NO 3 - , with Pearson correlation coefficients of 0.425, 0.531, 0.853, 0.612, and 0.329, respectively (p < 0.01). Elevated Ba concentrations in water indicated that the Ba contamination and its distribution pattern in local aquatic ecosystems are derived from Ba mining sites in the Tianzhu area.

  11. Temporal variations of 137Cs concentrations in the surface seawater and marine organisms collected from the Japanese coast during the 1980's

    International Nuclear Information System (INIS)

    Yamada, M.; Nagaya, Y.

    1998-01-01

    The surface seawater and marine organisms were collected on the Japanese coast and analyzed for their 137 Cs concentrations during the 1980's. The 137 Cs concentrations in surface seawater decreased almost exponentially with time and the 137 Cs removal rate constant was estimated to be 0.0445 y -1 . The 137 Cs concentrations in marine organisms also decreased almost exponentially with time. The environmental half-lives of 137 Cs in muscle and viscera of fish, crustacea, and seaweed were estimated from the measured decreases of 137 Cs concentrations. (author)

  12. Relationship between photosynthetic pigments and chlorophyll fluorescence in soybean under varying phosphorus nutrition at ambient and elevated CO2

    Science.gov (United States)

    Photosynthetic pigments such as chlorophyll (Chl) a, Chl b and carotenoids concentration, and chlorophyll fluorescence (CF) have widely been used as indicators of stress and photosynthetic performance in plants. Although photosynthetic pigments and CF are partly interdependent due to absorption and ...

  13. Quantification of leaf pigments in soybean (Glycine max (L.) Merr.) based on wavelet decomposition of hyperspectral features

    Science.gov (United States)

    Accurate prediction of leaf pigments from spectral reflectance is important because it allows non-destructive, rapid assessment of crop-N status under field conditions. Canopy reflectance and leaf pigments (chlorophyll and carotenoids concentration) were measured on 385 field grown soybean genotypes...

  14. [Effect of hydrofluoric acid concentration on the surface morphology and bonding effectiveness of lithium disilicate glass ceramics to resin composites].

    Science.gov (United States)

    Hailan, Qian; Lingyan, Ren; Rongrong, Nie; Xiangfeng, Meng

    2017-12-01

    This study aimed at determining the influence of hydrofluoric acid (HF) in varied concentrations on the surface morphology of lithium disilicate glass ceramics and bond durability between resin composites and post-treated lithium disilicate glass ceramics. After being sintered, ground, and washed, 72 as-prepared specimens of lithium disilicate glass ceramics with dimensions of 11 mm×13 mm×2 mm were randomly divided into three groups. Each group was treated with acid solution [32% phosphoric acid (PA) or 4% or 9.5% HF] for 20 s. Then, four acidified specimens from each group were randomly selected. One of the specimens was used to observe the surface morphology using scanning electron microscopy, and the others were used to observe the surface roughness using a surface roughness meter (including Ra, Rz, and Rmax). After treatment with different acid solutions in each group, 20 samples were further treated with silane coupling agent/resin adhesive/resin cement (Monobond S/Multilink Primer A&B/Multilink N), followed by bonding to a composite resin column (Filtek™ Z350) with a diameter of 3 mm. A total of 20 specimens in each group were randomly divided into two subgroups, which were used for measuring the microshear bond strength, with one of them subjected to cool-thermal cycle for 20 000 times. The surface roughness (Ra, Rz, and Rmax) of lithium disilicate glass ceramics treated with 4% or 9.5% HF was significantly higher than that of the ceramic treated with PA (Pglass ceramics treated with 9.5% HF also demonstrated better surface roughness (Rz and Rmax) than that of the ceramics treated with 4% HF. Cool-thermal cycle treatment reduced the bond strength of lithium disilicate glass ceramics in all groups (Pglass ceramics treated with HF had higher bond strength than that of the ceramics treated with PA. The lithium disilicate glass ceramics treated with 4% HF had higher bond strength than that of the ceramics treated with 9.5% HF (Pglass ceramics treated with 4

  15. Color stability of thermochromic pigment in maxillofacial silicone

    Science.gov (United States)

    Lassila, Lippo V.J.; Tolvanen, Mimmi; Valittu, Pekka K.

    2013-01-01

    PURPOSE Maxillofacial silicone elastomer is usually colored intrinsically with color pigments to match skin colors. The purpose of this study was to investigate the color stability of a maxillofacial silicone elastomer, colored with a thermochromic, color changing pigment. MATERIALS AND METHODS Disc-shaped maxillofacial silicone specimens were prepared and divided into 3 groups: a conventionally colored control group, one group additionally colored with 0.2 wt% thermochromic pigment , and one group with 0.6 wt% thermochromic pigment. Half of the surface of each specimen was covered with an aluminium foil. All of the specimens were exposed to UV radiation in 6 hour cycles over 46 days. In between the UV exposures, half of the specimens were stored in darkness, at room temperature, and the other half was stored in an incubator, at a humidity of 97% and a temperature of +37℃. Color measurements were made with a spectrophotometer and registered according to the CIELAB L*a*b* color model system. The changes in L*, a* and b* values during artificial aging were statistically analyzed by using paired samples t-test and repeated measures ANOVA. P-values maxillofacial prostheses. PMID:23755330

  16. Column chromatography as a useful step in purification of diatom pigments.

    Science.gov (United States)

    Tokarek, Wiktor; Listwan, Stanisław; Pagacz, Joanna; Leśniak, Piotr; Latowski, Dariusz

    2016-01-01

    Fucoxanthin, diadinoxanthin and diatoxanthin are carotenoids found in brown algae and most other heterokonts. These pigments are involved in photosynthetic and photoprotective reactions, and they have many potential health benefits. They can be extracted from diatom Phaeodactylum tricornutum by sonication, extraction with chloroform : methanol and preparative thin layer chromatography. We assessed the utility of an additional column chromatography step in purification of these pigments. This novel addition to the isolation protocol increased the purity of fucoxanthin and allowed for concentration of diadinoxanthin and diatoxanthin before HPLC separation. The enhanced protocol is useful for obtaining high purity pigments for biochemical studies.

  17. Colloidal assembly in Leidenfrost drops for noniridescent structural color pigments.

    Science.gov (United States)

    Lim, Che Ho; Kang, Hyelim; Kim, Shin-Hyun

    2014-07-22

    Noniridescent structural color pigments have great potential as alternatives to conventional chemical color pigments in many coloration applications due to their nonbleaching and color-tunable properties. In this work, we report a novel method to create photonic microgranules composed of glassy packing of silica particles and small fraction of carbon black nanoparticles, which show pronounced structural colors with low angle-dependency. To prepare isotropic random packing in each microgranule, a Leidenfrost drop, which is a drop levitated by its own vapor on a hot surface, is employed as a template for fast consolidation of silica particles. The drop randomly migrates over the hot surface and rapidly shrinks, while maintaining its spherical shape, thereby consolidating silica particles to granular structures. Carbon black nanoparticles incorporated in the microgranules suppress incoherent multiple scattering, thereby providing improved color contrast. Therefore, photonic microgranules in a full visible range can be prepared by adjusting the size of silica particles with insignificant whitening.

  18. Improvement of Dispersion and Color Effect of Organic Pigments in Polymeric Films via Microencapsulation by the Miniemulsion Technique

    Directory of Open Access Journals (Sweden)

    Dongming Qi

    2013-01-01

    Full Text Available Three primary pigment/poly(n-butyl acrylate-co-styrene (P(BA+St nanocomposites were prepared via encapsulation of the corresponding organic pigments via the miniemulsion technique. The resulting latexes of the P(BA+St/pigment nanocomposites were filmed in a PTFE mould or printed onto cotton fabric. The morphology of the P(BA+St/pigment nanocomposites and the dispersion of pigment particles in the latex film and on the printed fabric surface, as well as the adhesion between pigment and adhesive film, were evaluated by transmission electron microscopy (TEM, field emission scanning electron microscopy (FESEM, 3D digital microscope system (3D-POM, and printing results tests. Attributing to the preprotection of adhesive polymer shell, the self-adhesive P(BA+St/pigment nanocomposites were homogeneously and firmly dispersed both in the thin latex film and in the adhesive layer on the fiber surface. As a result, the color strength, color fastness, and handle of the fabrics printed by the P(BA+St/pigment nanocomposites latex were significantly improved, compared to the fabrics printed by the conventional pigment blended latex.

  19. Dissolution rate measurements of sea water soluble pigments for antifouling paints

    DEFF Research Database (Denmark)

    Yebra, Diego Meseguer; Kiil, Søren; Erik Weinell, Claus

    2006-01-01

    The dissolution of soluble pigments from both tin-based and tin-free chemically active antifouling (AF) paints is a key process influencing their polishing and biocide leaching rates. In this context, a low time- and resources-consuming method capable of screening the pigment behaviour.......3 +/- 3.7 mu g Zn2+ cm(-2) day(-1), pellets prepared by compacting and sintering technical grade ZnO pigments dissolved about three times faster according to inductively-coupled plasma mass spectrometry (ICP-MS) measurements. The rougher and more porous surface exposed, together with the larger number...

  20. Optimal number of pigments in photosynthetic complexes

    International Nuclear Information System (INIS)

    Jesenko, Simon; Žnidarič, Marko

    2012-01-01

    We study excitation energy transfer in a simple model of a photosynthetic complex. The model, described by the Lindblad equation, consists of pigments interacting via dipole–dipole interaction. The overlapping of pigments induces an on-site energy disorder, providing a mechanism for blocking the excitation transfer. Based on the average efficiency as well as the robustness of random configurations of pigments, we calculate the optimal number of pigments that should be enclosed in a pigment–protein complex of a given size. The results suggest that a large fraction of pigment configurations are efficient as well as robust if the number of pigments is properly chosen. We compare the optimal results of the model to the structure of pigment–protein complexes as found in nature, finding good agreement. (paper)

  1. Changing oxidoreduction potential to improve water-soluble yellow pigment production with Monascus ruber CGMCC 10910.

    Science.gov (United States)

    Huang, Tao; Tan, Hailing; Lu, Fangju; Chen, Gong; Wu, Zhenqiang

    2017-11-21

    Monascus pigments are widely used in the food and pharmaceutical industries due to their safety to human health. Our previous study found that glucose concentration induced extracellular oxidoreduction potential (ORP) changes could influence extracellular water-soluble yellow pigment production by Monascus ruber CGMCC 10910 in submerged fermentation. In this study, H 2 O 2 and dithiothreitol (DTT) were used to change the oxidoreduction potential for investigating the effects of oxidative or reductive substances on Monascus yellow pigment production by Monascus ruber CGMCC 10910. The extracellular ORP could be controlled by H 2 O 2 and DTT. Both cell growth and extracellular water-soluble yellow pigment production were enhanced under H 2 O 2 -induced oxidative (HIO) conditions and were inhibited under dithiothreitol-induced reductive conditions. By optimizing the amount of H 2 O 2 added and the timing of the addition, the yield of extracellular water-soluble yellow pigments significantly increased and reached a maximum of 209 AU, when 10 mM H 2 O 2 was added on the 3rd day of fermentation with M. ruber CGMCC 10910. Under HIO conditions, the ratio of NADH/NAD+ was much lower than that in the control group, and the expression levels of relative pigment biosynthesis genes were up-regulated; moreover, the activity of glucose-6-phosphate dehydrogenase (G6PDH) was increased while 6-phosphofructokinase (PFK) activity was inhibited. Oxidative conditions induced by H 2 O 2 increased water-soluble yellow pigment accumulation via up-regulation of the expression levels of relative genes and by increasing the precursors of pigment biosynthesis through redirection of metabolic flux. In contrast, reductive conditions induced by dithiothreitol inhibited yellow pigment accumulation. This experiment provides a potential strategy for improving the production of Monascus yellow pigments.

  2. The application of ion-exchanged clay as corrosion inhibiting pigments in organic coatings

    Science.gov (United States)

    Chrisanti, Santi

    High strength aluminum alloys are used in aerospace industry and are normally coated to prevent corrosion. The corrosion protection of the coatings is mainly provided by pigmented-primer layer. Strontium chromate pigments are widely used, but they are toxic and carcinogenic. The objective of the current study is to develop and characterize the ion exchange compounds bentonite and hydrotalcite as corrosion inhibiting pigments. These compounds were synthesized with different cations and anions, and were used either alone or in mixtures as particulate additive in organic coatings. In coating applications as well as bulk solution, the inhibitor release mechanism is based on ion exchange. To evaluate corrosion inhibition, pigments extract solutions were used in potentiodynamic polarization as well as electrochemical impedance spectroscopy (EIS) experiments on bare aluminum alloy 2024-T3. Cathodic polarization showed that zinc- and cerium-containing filtrate solutions modestly inhibited cathodic current density. These solutions also decreased the extent of pitting damage formed on the surface, as compared to uninhibited 0.5 M NaCl solution. Pigments were also added as primer additives, and painted on AA2024-T3. The coated panels were then subjected to salt spray exposure testing. The possibility of sensing inhibitor exhaustion by means of X-ray diffraction interrogation of the pigment in a coating is demonstrated and discussed on cerium bentonite-pigmented coatings. Although cerium bentonite-pigmented coatings did not show behavior indicative of self-healing, the combination of bentonite and hydrotalcite that released Ce3+, Zn 2+, and PO43- showed potent scribe protection even after 3000 h exposure in salt spray. Promising self-healing was also demonstrated by pigments that consisted of decavanadate-hydrotalcite and zinc pyrovanadate, as indicated by a shiny scribed area after 1000h exposure in salt spray. When these pigments are used, blistering is minimized.

  3. Pigmented xerodermoid - Report of three cases

    OpenAIRE

    Das Jayanta Kumar; Gangopadhyay Asok Kumar

    2005-01-01

    Pigmented xerodermoid, a rare genodermatosis, presents with clinical features and pathology similar to xeroderma pigmentosum, but at a later age. DNA repair replication is normal, but there is total depression of DNA synthesis after exposure to UV radiation. Two siblings in their teens and a man in his thirties with features of pigmented xerodermoid, e.g. photophobia, freckle-like lesions, keratoses, dryness of skin, and hypo- and hyper-pigmentation, are described. Although classically the on...

  4. Production of Monascus-like azaphilone Pigment

    DEFF Research Database (Denmark)

    2009-01-01

    The present invention relates to the field of biotechnological production of polyketide based colorants from filamentous fungi, in particular a method for preparing a biomass comprising a Monascus-like pigment composition from a nontoxigenic and non-pathogenic fungal source. The present invention...... further relates to use of the Monascus-like pigment composition as a colouring agent for food items and/or non-food items, and a cosmetic composition comprising the Monascus-like pigment composition....

  5. PRODUCTION OF MONASCUS-LIKE AZAPHILONE PIGMENT

    DEFF Research Database (Denmark)

    2009-01-01

    The present invention relates to the field of biotechnological production of polyketide based colorants from filamentous fungi, in particular a method for preparing a biomass comprising a Monascus-like pigment composition from a nontoxigenic and non-pathogenic fungal source. The present invention...... further relates to use of the Monascus-like pigment composition as a colouring agent for food items and/or non-food items, and a cosmetic composition comprising the Monascus-like pigment composition....

  6. Electron crystallography of organic pigments

    Energy Technology Data Exchange (ETDEWEB)

    Boyce, G

    1997-10-01

    The principle aim of this thesis is the detailing of the development and subsequent use of electron crystallographic techniques which employ the maximum entropy approach. An account is given of the electron microscope as a crystallographic instrument, along with the necessary theory involved. Also, an overview of the development of electron crystallography, as a whole, is given. This progresses to a description of the maximum entropy methodology and how use can be made of electron diffraction data in ab initio phasing techniques. Details are also given of the utilisation of image derived phases in the determination of structural information. Extensive examples are given of the use of the maximum entropy program MICE, as applied to a variety of structural problems. A particular area of interest covered by this thesis is regarding the solid state structure of organic pigments. A detailed structure review of both {beta}-naphthol and acetoacetanilide pigments was undertaken. Information gained from this review was used as a starting point for the attempted structural elucidation of a related pigment, Barium Lake Red C. Details are given of the synthesis, electron microscope studies and subsequent ab initio phasing procedures applied in the determination of structural information on Barium Lake Red C. The final sections of this thesis detail electron crystallographic analyses of three quite different structures. Common to all was the use of maximum entropy methods, both for ab initio phasing and use of image derived phases. Overall, it is shown that electron crystallographic structure analyses using maximum entropy methods are successful using electron diffraction data and do provide distinct structural information even when significant perturbations to the data exist. (author)

  7. Passive ionic properties of frog retinal pigment epithelium.

    Science.gov (United States)

    Miller, S S; Steinberg, R H

    1977-09-15

    The isolated pigment epithelium and choroid of frog was mounted in a chamber so that the apical surfaces of the epithelial cells and the choroid were exposed to separate solutions. The apical membrane of these cells was penetrated with microelectrodes and the mean apical membrane potential was --88 mV. The basal membrane potential was depolarized by the amount of the transepithelial potential (8--20 mV). Changes in apical and basal cell membrane voltage were produced by changing ion concentrations on one or both sides of the tissue. Although these voltage changes were altered by shunting and changes in membrane resistance, it was possible to estimate apical and basal cell membrane and shunt resistance, and the relative ionic conductance Ti of each membrane. For the apical membrane: TK approximately equal to 0.52, THCO3 approximately equal to 0.39 and TNa approximately equal to 0.05, and its specific resistance was estimated to be 6000--7000 omega cm2. For the basal membrane: TK approximately equal to 0.90 and its specific resistance was estimated to be 400--1200 omega cm2. From the basal potassium voltage responses the intracellular potassium concentration was estimated at 110 mM. The shunt resistance consisted of two pathways: a paracellular one, due to the junctional complexes and another, around the edge of the tissue, due to the imperfect nature of the mechanical seal. In well-sealed tissues, the specific resistance of the shunt was about ten times the apical plus basal membrane specific resistances. This epithelium, therefore, should be considered "tight". The shunt pathway did not distinguish between anions (HCO--3, Cl--, methylsulfate, isethionate) but did distinguish between Na+ and K+.

  8. Concentration patterns of agricultural pesticides and urban biocides in surface waters of a catchment of mixed land use

    Science.gov (United States)

    Stamm, C.; Wittmer, I.; Bader, H.-P.; Scheidegger, R.; Alder, A.; Lück, A.; Hanke, I.; Singer, H.

    2009-04-01

    Organic pesticides and biocides that are found in surface waters, can originate from agricultural and urban sources. For a long time, agricultural pesticides have received substantially more attention than biocidal compounds from urban use like material protection or in-can preservatives (cosmetics etc.). Recent studies however revealed that the amounts of urban biocides used may exceed those of agricultural pesticides. This study aims at comparing the input of several important pesticides and biocides into a small Swiss stream with a special focus on loss events triggered by rainfall. A set of 16 substances was selected to represent urban and agricultural sources. The selected substances are either only used as biocides (irgarol, isothiazolinones, IPBC), as pesticides (atrazine, sulcotrione, dichlofluanid, tolylfluanid) or have a mixed use (isoproturon, terbutryn, terbutylazine, mecoprop, diazinon, carbendazim) The study catchment has an area of 25 km2 and is inhabited by about 12'000 people. Four sampling sites were selected in the river system in order to reflect different urban and agricultural sources. Additionally, we sampled a combined sewer overflow, a rain sewer and the outflow of a wastewater treatment plant. At each site discharge was measured continuously from March to November 2007. During 16 rain events samples were taken by automatic devices at a high temporal resolution. The results, based on more than 500 analyzed samples, revealed distinct concentration patterns for different compounds and sources. Agricultural pesticides exhibited a strong seasonality as expected based on the application periods. During the first one or two rain events after application the concentrations reached up to several thousand ng/l during peak flow (atrazine, isoproturon). The temporal patterns of urban biocides were more diverse. Some compounds obviously stem from permanent sources independent of rainfall because they were found mostly in the outlet of the wastewater

  9. The biogeochemistry of tetrapyrrole pigments, emphasizing chlorophyll

    Energy Technology Data Exchange (ETDEWEB)

    Louda, J.W.

    1993-01-01

    Electronic absorption spectra recorded on native geopigments and on in vitro derivatives, obtained with combinations of copper insertion and borohydride reduction reactions, allowed a sensitive chromophore identification' scheme to be developed. Quantitation of the Ni and VO geoporphyrins, as well as the benzo-forms of each, was tested and precisions at the level of 100 [+-] 5% found. An overall methodology for obtaining repeatable low-voltage mass spectra on geoporphyrin arrays is presented. Repeatabilities for the various mass spectral-derived indices were; %DPEP ([+-]2%), X ([+-]2%), A.I.([+-]5%) and % BENZ ([+-]10%). Quantitation of the metallobenzoporphyrins was much better ([+-]2%) with UV/VIS techniques. Tetrapyrrole geochemistry was investigated at all stages of organic evolution. Thus, viable and senescent/dead uni-algal cultures, sediment trap material, surface (<1m) sediments, deep ocean long cores (DSDP), oil shales and petroleum crudes were investigated. Results indicate that the chlorophylls can serve as sources for a variety of geoporphyrins. Early in diagenesis two competing reactions dictate further fossilization.' First is the loss of the carbomethoxy group. This produces pyropheophorbides which can either lead to the true DPEP series, via a sequence of defunctionaliation reactions or, via intramolecular cyclization (dehydration), to certain 13[sup 2], 17[sup 3]-cyclopheophorbide enols. The latter, following defunctionalization, give rise to DiDPEP and/or DPEP-type pigments with a 7-membered exocyclic ring. Second, chlorophyll nuclei which have undergone oxidative scission of the isocyclic ring can, through purpurins and chlorins, theoretically yield C28-C30 ETIO-series porphyrins. Bacteriochlorophyll-a was found to be a dominant pigment in several anoxic sediments and is suggested as an important and highly specific precursor for certain geoporphyrins (i.e 3-methyl-desethyl-DPEP).

  10. Reformulated and alternative fuels: modeled impacts on regional air quality with special emphasis on surface ozone concentration.

    Science.gov (United States)

    Schell, Benedikt; Ackermann, Ingmar J; Hass, Heinz

    2002-07-15

    The comprehensive European Air Pollution and Dispersion model system was used to estimate the impacts of the usage of reformulated and alternative fuels on regional air quality with special emphasis on surface ozone concentrations. A severe western European summer smog episode in July 1994 has been used as a reference, and the model predictions have been evaluated for this episode. A forecast simulation for the year 2005 (TREND) has been performed, including the future emission development based on the current legislation and technologies available. The results of the scenario TREND are used as a baseline for the other 2005 fuel scenarios, including fuel reformulation, fuel sulfur content, and compressed natural gas (CNG) as an alternative fuel. Compared to the year 1994, significant reductions in episode peak ozone concentrations and ozone grid hours are predicted for the TREND scenario. These reductions are even more pronounced within the investigated alternative and reformulated fuel scenarios. Especially, low sulfur fuels are appropriate for an immediate improvement in air quality, because they effect the emissions of the whole fleet. Furthermore, the simulation results indicate that the introduction of CNG vehicles would also enhance air quality with respect to ozone.

  11. Definition of intrusion scenarios and example concentration ranges for the disposal of near-surface waste at the Hanford Site

    International Nuclear Information System (INIS)

    Aaberg, R.L.; Kennedy, W.E. Jr.

    1990-10-01

    The US Department of Energy (DOE) is in the process of conducting performance assessments of its radioactive waste sites and disposal systems to ensure that public health and safety are protected, the environment is preserved, and that no remedial actions after disposal are required. Hanford Site low-level waste performance assessments are technical evaluations of waste sites or disposal systems that provide a basis for making decisions using established criteria. The purpose of this document is to provide a family of scenarios to be considered when calculating radionuclide exposure to individuals who may inadvertently intrude into near-surface waste disposal sites. Specific performance assessments will use modifications of the general scenarios described here to include additional site/system details concerning the engineering design, waste form, inventory, and environmental setting. This document also describes and example application of the Hanford-specific scenarios in the development of example concentration ranges for the disposal of near-surface wastes. The overall goal of the example calculations is to illustrate the application of the scenarios in a performance assessment to assure that people in the future cannot receive a dose greater than an established limit. 24 refs., 2 figs., 5 tabs

  12. Sea ice concentration temporal variability over the Weddell Sea and its relationship with tropical sea surface temperature

    Science.gov (United States)

    Barreira, S.; Compagnucci, R.

    2007-01-01

    Principal Components Analysis (PCA) in S-Mode (correlation between temporal series) was performed on sea ice monthly anomalies, in order to investigate which are the main temporal patterns, where are the homogenous areas located and how are they related to the sea surface temperature (SST). This analysis provides 9 patterns (4 in the Amundsen and Bellingshausen Seas and 5 in the Weddell Sea) that represent the most important temporal features that dominated sea ice concentration anomalies (SICA) variability in the Weddell, Amundsen and Bellingshausen Seas over the 1979-2000 period. Monthly Polar Gridded Sea Ice Concentrations data set derived from satellite information generated by NASA Team algorithm and acquired from the National Snow and Ice Data Center (NSIDC) were used. Monthly means SST are provided by the National Center for Environmental Prediction reanalysis. The first temporal pattern series obtained by PCA has its homogeneous area located at the external region of the Weddell and Bellingshausen Seas and Drake Passage, mostly north of 60°S. The second region is centered in 30°W and located at the southeast of the Weddell. The third area is localized east of 30°W and north of 60°S. South of the first area, the fourth PC series has its homogenous region, between 30° and 60°W. The last area is centered at 0° W and south of 60°S. Correlation charts between the five Principal Components series and SST were performed. Positive correlations over the Tropical Pacific Ocean were found for the five PCs when SST series preceded SICA PC series. The sign of the correlation could relate the occurrence of an El Niño/Southern Oscillation (ENSO) warm (cold) event with posterior positive (negative) anomalies of sea ice concentration over the Weddell Sea.

  13. Assessment of the total uranium concentration in surface and underground water samples from the Caetite region, Bahia, Brazil

    International Nuclear Information System (INIS)

    Silva, Julia Grasiela Batista; Geraldo, Luiz Paulo; Yamazaki, Ione Makiko

    2011-01-01

    At the region of Caetite, BA, it is located the largest uranium mine in exploration at present days in Brazil. During the uranium extraction process, it may be having an environmental contamination by this heavy metal due to rain water and other natural transport mechanism, with potential exposition risk to the local population. The aim of this work was to investigate the total uranium concentration in surface and underground water samples collected at the Caetite region, using the nuclear track registration technique (SSNTD) in a polycarbonate plastic. A 100 mL volume of water samples were initially treated in 10 mL of HNO 3 (PA) and concentrated by evaporation at a temperature around 80 deg C. The resulting residue was diluted to a total volume of 25 mL without pass it to a filter. About 10 μL of this solution was deposited on the plastic detector surface (around 1.0 cm 2 area) together with 5 μL of a Cyastat detergent solution (5%) and evaporated under an infrared lamp. All the resulting deposits of non volatile constituents were irradiated, together with a uranium standard sample, at the IPEN-IEA-R1 (3.5 MW) nuclear reactor for approximately 3 min. After irradiations, chemical etching of the plastic detectors was carried out at 60 deg C, for 65 min. in a NaOH (6N) solution. The fission tracks were counted scanning all the deposit area of the polycarbonate plastic detector with a system consisting of an optical microscope together with a video camera and TV monitor. The average values of uranium concentrations obtained in this work ranged from (0.95±0.19) μg.L -1 to (25.60±3.3) μg.L -1 . These results were compared to values reported in the literature for water samples from other regions and discussed in terms of safe limits recommended by WHO -World Health Organization and CONAMA - Conselho Nacional do Meio Ambiente. (author)

  14. Assessment of the total uranium concentration in surface and underground water samples from the Caetite region, Bahia, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Julia Grasiela Batista; Geraldo, Luiz Paulo [Centro Universitario da Fundacao Educacional de Barretos (UNIFEB), (SP) (Brazil); Yamazaki, Ione Makiko [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    At the region of Caetite, BA, it is located the largest uranium mine in exploration at present days in Brazil. During the uranium extraction process, it may be having an environmental contamination by this heavy metal due to rain water and other natural transport mechanism, with potential exposition risk to the local population. The aim of this work was to investigate the total uranium concentration in surface and underground water samples collected at the Caetite region, using the nuclear track registration technique (SSNTD) in a polycarbonate plastic. A 100 mL volume of water samples were initially treated in 10 mL of HNO{sub 3} (PA) and concentrated by evaporation at a temperature around 80 deg C. The resulting residue was diluted to a total volume of 25 mL without pass it to a filter. About 10 {mu}L of this solution was deposited on the plastic detector surface (around 1.0 cm{sup 2} area) together with 5 {mu}L of a Cyastat detergent solution (5%) and evaporated under an infrared lamp. All the resulting deposits of non volatile constituents were irradiated, together with a uranium standard sample, at the IPEN-IEA-R1 (3.5 MW) nuclear reactor for approximately 3 min. After irradiations, chemical etching of the plastic detectors was carried out at 60 deg C, for 65 min. in a NaOH (6N) solution. The fission tracks were counted scanning all the deposit area of the polycarbonate plastic detector with a system consisting of an optical microscope together with a video camera and TV monitor. The average values of uranium concentrations obtained in this work ranged from (0.95{+-}0.19) {mu}g.L{sup -1} to (25.60{+-}3.3) {mu}g.L{sup -1}. These results were compared to values reported in the literature for water samples from other regions and discussed in terms of safe limits recommended by WHO -World Health Organization and CONAMA - Conselho Nacional do Meio Ambiente. (author)

  15. STABILITY OF BETACYANIN PIGMENTS FROM RED PURPLE PITAYA FRUIT (Hylocereus polyrhizus : INFLUENCE OF PH, TEMPERATURE, METAL IONS AND ASCORBIC ACID

    Directory of Open Access Journals (Sweden)

    Tang, C.S Tang, C.S

    2010-06-01

    Full Text Available Betacyanin pigments from red-purple pitaya fruit (Hylocereus polyrhizus could be an attractive source of red colourant for food application. This paper presents results on the extraction of betacyanin pigments from pitaya fruits grown locally in Malaysia. Both the flesh of the fruit and its mesocarp were investigated and it was found that the flesh had higher pigment contents compared to its peel component. The concentration of betacyanins expressed as betanin equivalents per 100 g of flesh and peel were 10.1 ± 0.6 mg and 6.7 ± 0.2 mg, respectively when 80% methanol was used.  The stability of betacyanin pigments were investigated at different pH, temperature and in presence of different concentrations of metal ions (Cu2+ and Fe2+ and ascorbic acid. The results showed that the pigment was most stable at pH range between 5 and 6. However, it forfeited its stability to the heat induced at elevated temperatures. Metal ions (Cu2+ and Fe2+ proved to be capable of accelerating betacyanin degradation, with Cu2+ exhibiting the greatest effect. By contrast, supplementation with ascorbic acid could enhance the pigment stability against the detrimental effects caused by pH, temperature and metal ions. Nevertheless, if the concentration of ascorbic acid exceeds 0.7 %, it may change its role from pigment stabilizer to become a pro-oxidant.    Keywords: Betacyanin, pigments, pitaya fruit, Hylocereus polyrhizus, ascorbic acid

  16. Ocular distribution of topically applied adrenaline in albino and pigmented rabbits

    International Nuclear Information System (INIS)

    Urtti, A.; Periviita, L.; Salminen, L.

    1984-01-01

    Systemic absorption, ocular distribution and ocular metabolism in albino and pigmented rabbit of topically applied 1% [ 3 H]1-adrenaline eye drops was studied by liquid scintillation counting and thin layer chromatography. The effect of adrenaline on the pupillary diameter was also registered. The peak plasma level of adrenaline was reached at 150 min. The corneal adrenaline metabolism was substantial, but did not vary with the rabbit strain. At 30 min after instillation, the total adrenaline concentration of pigmented iris and ciliary body exceeded that of corresponding albino tissues. At 180 min the drug concentration of the iris and ciliary body did not differ between the rabbit strains. Th time course of adrenaline induced mydriasis was equal in both rabbit strains. Since neither total adrenaline concentration at 180 min nor the time course of adrenaline induced mydriasis differed between the rabbit strains, the higher initial adrenaline uptake by pigmented tissues is not explained by pigment binding. It is proposed that the increased initial binding of adrenaline by pigmented tissues is caused by a difference between pigmented and albino tissues in the number of adrenergic neurones; this is also supported by the literature. (author)

  17. Bacterial communities in pigmented biofilms formed on the sandstone bas-relief walls of the Bayon Temple, Angkor Thom, Cambodia.

    Science.gov (United States)

    Kusumi, Asako; Li, Xianshu; Osuga, Yu; Kawashima, Arata; Gu, Ji-Dong; Nasu, Masao; Katayama, Yoko

    2013-01-01

    The Bayon temple in Angkor Thom, Cambodia has shown serious deterioration and is subject to the formation of various pigmented biofilms. Because biofilms are damaging the bas-reliefs, low reliefs engraved on the surface of sandstone, information about the microbial community within them is indispensable to control biofilm colonization. PCR-denaturing gradient gel electrophoresis (DGGE) analysis of biofilm samples from the pigmented sandstone surfaces showed that the bacterial community members in the biofilms differed clearly from those in the air and had low sequence similarity to database sequences. Non-destructive sampling of biofilm revealed novel bacterial groups of predominantly Rubrobacter in salmon pink biofilm, Cyanobacteria in chrome green biofilm, Cyanobacteria and Chloroflexi in signal violet biofilm, Chloroflexi in black gray biofilm, and Deinococcus-Thermus, Cyanobacteria, and Rubrobacter in blue green biofilm. Serial peeling-off of a thick biofilm by layers with adhesive sheets revealed a stratified structure: the blue-green biofilm, around which there was serious deterioration, was very rich in Cyanobacteria near the surface and Chloroflexi in deep layer below. Nitrate ion concentrations were high in the blue-green biofilm. The characteristic distribution of bacteria at different biofilm depths provides valuable information on not only the biofilm formation process but also the sandstone weathering process in the tropics.

  18. Down-regulation of Cell Surface Cyclic AMP Receptors and Desensitization of Cyclic AMP-stimulated Adenylate Cyclase by Cyclic AMP in Dictyostelium discoideum. Kinetics and Concentration Dependence

    NARCIS (Netherlands)

    Haastert, Peter J.M. van

    1987-01-01

    cAMP binds to Dictyostelium discoideum surface receptors and induces a transient activation of adenylate cyclase, which is followed by desensitization. cAMP also induces a loss of detectable surface receptors (down-regulation). Cells were incubated with constant cAMP concentrations, washed free of

  19. Fuzzy Clustering-Based Modeling of Surface Interactions and Emulsions of Selected Whey Protein Concentrate Combined to i-Carrageenan and Gum Arabic Solutions

    Science.gov (United States)

    Gums and proteins are valuable ingredients with a wide spectrum of applications. Surface properties (surface tension, interfacial tension, emulsion activity index “EAI” and emulsion stability index “ESI”) of 4% whey protein concentrate (WPC) in a combination with '- carrageenan (0.05%, 0.1%, and 0.5...

  20. The effect of salicylic acid and acetylsalicylic acid on red pigment formation in mechanically wounded scales of Hippeastrum x hybr. hort. and on the growth and development of Phoma narcissi

    Directory of Open Access Journals (Sweden)

    Alicja Saniewska

    2012-12-01

    Full Text Available Various organs of Hippeastrum infected by Phoma narcissi, infested with mite, Steneotarsonemus laticeps or mechanically wounded, produce red pigment on the surface of injured tissues. The aim of the present work was to study the effect of salicylic (SA and acetylsalicylic acids (ASA (inhibitors of biosynthesis of jasmonates and ethylene on red pigment formation in wounded scales of bulbs of Hippeastrum and on the mycelium growth of P. narcissi in vivo and in vitro. SA and ASA at a concentration of 1 and 2 mM partially inhibited the formation of red pigment in wounded scales, first of all in first 2 days after treatment. The growth and development of P. narcissi on basal plate and scales of longitudinally cut Hippeastrum bulb treated with SA and ASA (1 and 2 mM was similar as in control. SA (50 µg·cm-3 and ASA (250 µg·cm-3 inhibited the mycelium growth of P. narcissi on PDA medium, and concentration of 1000 µg·cm-3 of both almost totally inhibited the mycelium growth of the pathogen. Inhibitory effect of SA and ASA on the formation of red pigment in wounded scales of Hippeastrum may be caused by lowered biosynthesis and accumulation of jasmonates.

  1. Nitisinone improves eye and skin pigmentation defects in a mouse model of oculocutaneous albinism.

    Science.gov (United States)

    Onojafe, Ighovie F; Adams, David R; Simeonov, Dimitre R; Zhang, Jun; Chan, Chi-Chao; Bernardini, Isa M; Sergeev, Yuri V; Dolinska, Monika B; Alur, Ramakrishna P; Brilliant, Murray H; Gahl, William A; Brooks, Brian P

    2011-10-01

    Mutation of the tyrosinase gene (TYR) causes oculocutaneous albinism, type 1 (OCA1), a condition characterized by reduced skin and eye melanin pigmentation and by vision loss. The retinal pigment epithelium influences postnatal visual development. Therefore, increasing ocular pigmentation in patients with OCA1 might enhance visual function. There are 2 forms of OCA1, OCA-1A and OCA-1B. Individuals with the former lack functional tyrosinase and therefore lack melanin, while individuals with the latter produce some melanin. We hypothesized that increasing plasma tyrosine concentrations using nitisinone, an FDA-approved inhibitor of tyrosine degradation, could stabilize tyrosinase and improve pigmentation in individuals with OCA1. Here, we tested this hypothesis in mice homozygous for either the Tyrc-2J null allele or the Tyrc-h allele, which model OCA-1A and OCA-1B, respectively. Only nitisinone-treated Tyrc-h/c-h mice manifested increased pigmentation in their fur and irides and had more pigmented melanosomes. High levels of tyrosine improved the stability and enzymatic function of the Tyrc-h protein and also increased overall melanin levels in melanocytes from a human with OCA-1B. These results suggest that the use of nitisinone in OCA-1B patients could improve their pigmentation and potentially ameliorate vision loss.

  2. Effect of submerged and solid-state fermentation on pigment and citrinin production by Monascus purpureus.

    Science.gov (United States)

    Zhang, Liang; Li, Zhiqiang; Dai, Bing; Zhang, Wenxue; Yuan, Yongjun

    2013-09-01

    Monascus pigments, which are produced by various species of Monascus, often have been used as a natural colourant and as traditional natural food additives, especially in Southern China, Japan and Southeastern Asia. The limitation of wide using Monascus pigment is attributed to one of its secondary metabolites named citrinin. The aim of this study was to investigate the influence of pigment and citrinin production via submerged fermentation (SmF) and solid-state fermentation (SF) from rice (Oryza sativa L.) by Monascus purpureus AS3.531. The optimal fermentation temperature and pH were significantly different for pigment production through different fermentation mode (35 °C, pH 5.0 for SF and 32 °C, pH 5.5 for SmF, respectively). Adding 2% (w/v) of glycerol in the medium could enhance the pigment production. On the optimized condition, although the concentration of citrinin produced by SmF (19.02 ug/g) increased more than 100 times than that by SF (0.018 ug/g), the pigment yield by SmF (7.93 U/g/g) could be comparable to that by SF (6.63 U/g/g). Those indicate us that fermentation mode seems to be the primary factor which influence the citrinin yield and secondary factor for pigment production.

  3. Use of red pigment extracted from eggplant (Solanum melongena L.) peels as natural antioxidant and colorant

    International Nuclear Information System (INIS)

    Abdeldaiem, M. H.

    2013-01-01

    The present study was carried out to extract of red pigment from eggplant (Solanum melongena L.) peels by using ethanol ( 70%) acidified with 1.5N HCl ( 85:15 v/v). In addition to study the effect of gamma irradiation at dose levels of 0, 2, 4 and 6 kGy on total phenolic compounds, total antioxidant activity and total anthocyanins of red pigment extracted from eggplant peels and the effect of using non-irradiated pigment as food colorants on the sensory attributes of food items used. The results illustrated that the non-irradiated red pigment extracted from eggplant peel samples had a higher content of total phenolic compounds, total anthocyanins and exhibited high antioxidant activities compared with irradiated samples. Thus, based on these results, the effect ph values ( 1 and 10) and heat treatment ( 50 and 100°C) on color stability and on retention anthocyanins, respectively in samples of non-irradiated red pigment extracted from eggplant peel samples were investigated. Furthermore, the results showed that the concentration of color changes with the values of ph, where he was more concentrated at low values of ph. Also, the results exhibited retain the red pigment extracted from the eggplant peels high concentrations of authenticity after heat treatment at different temperatures and for different periods. Moreover, the results of sensory evaluation obvious that the natural red pigment extracted from eggplant peels could be blended with meat products beef sausage, some fruit juices such as strawberry, red grape and pomegranate to substitute the losses that may occur in the anthocyanins during heat treatments as pasteurization. Therefore, this study suggested that the red pigment extracted from eggplant can be used as natural food additives to increase antioxidant activity and colorant in many foods as an alternative to synthetic dyes that are harmful to health effects.

  4. Glucose metabolism in rat retinal pigment epithelium.

    Science.gov (United States)

    Coffe, Víctor; Carbajal, Raymundo C; Salceda, Rocío

    2006-01-01

    The retinal pigment epithelium (RPE) is the major transport pathway for exchange of metabolites and ions between choroidal blood supply and the neural retina. To gain insight into the mechanisms controlling glucose metabolism in RPE and its possible relationship to retinopathy, we studied the influence of different glucose concentrations on glycogen and lactate levels and CO(2) production in RPE from normal and streptozotocin-treated diabetic rats. Incubation of normal RPE in the absence of glucose caused a decrease in lactate production and glycogen content. In normal RPE, increasing glucose concentrations from 5.6 mM to 30 mM caused a four-fold increase in glucose accumulation and CO(2) yield, as well as reduction in lactate and glycogen production. In RPE from diabetic rats glucose accumulation did not increase in the presence of high glucose substrate, but it showed a four- and a seven-fold increase in CO(2) production through the mitochondrial and pentose phosphate pathways, respectively. We found high glycogen levels in RPE which can be used as an energy reserve for RPE itself and/or neural retina. Findings further show that the RPE possesses a high oxidative capacity. The large increase in glucose shunting to the pentose phosphate pathway in diabetic retina exposed to high glucose suggests a need for reducing capacity, consistent with increased oxidative stress.

  5. Characterizing estuarine plume discharge into the coastal ocean using fatty acid biomarkers and pigment analysis.

    Science.gov (United States)

    Fischer, Andrew M; Ryan, John P; Levesque, Christian; Welschmeyer, Nicholas

    2014-08-01

    The transformation of estuaries by human activities continues to alter the biogeochemical balance of the coastal ocean. The disruption of this balance can negatively impact the provision of goods and services, including fisheries, commerce and transportation, recreation and esthetic enjoyment. Here we examine a link, between the Elkhorn Slough and the coastal ocean in Monterey Bay, California (USA) using a novel application of fatty acid and pigment analysis. Fatty acid analysis of filtered water samples showed biologically distinct water types between the Elkhorn Slough plume and the receiving waters of the coastal ocean. A remarkable feature of the biological content of the plume entering the coastal ocean was the abundance of bacteria-specific fatty acids, which correlated well with concentrations of colored dissolved organic matter (CDOM). Pigment analysis showed that plume waters contained higher concentrations of diatoms and cryptophytes, while the coastal ocean waters showed higher relative concentrations of dinoflagellates. Bacteria and cryptophytes can provide a source of labile, energy-rich organic matter that may be locally important as a source of food for pelagic and benthic communities. Surface and depth surveys of the plume show that the biogeochemical constituents of the slough waters are injected into the coastal waters and become entrained in the northward flowing, nearshore current of Monterey Bay. Transport of these materials to the northern portion of the bay can fuel a bloom incubator, which exists in this region. This study shows that fatty acid markers can reveal the biogeochemical interactions between estuaries and the coastal ocean and highlights how man-made changes have the potential to influence coastal ecological change. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. The relationship between the violet pigment PP-V production and intracellular ammonium level in Penicillium purpurogenum.

    Science.gov (United States)

    Kojima, Ryo; Arai, Teppei; Matsufuji, Hiroshi; Kasumi, Takafumi; Watanabe, Taisuke; Ogihara, Jun

    2016-12-01

    Penicillium purpurogenum is the fungus that produces an azaphilone pigment. However, details about the pigment biosynthesis pathway are unknown. The violet pigment PP-V is the one of the main pigments biosynthesized by this fungus. This pigment contains an amino group in a pyran ring as its core structure. We focused on this pigment and examined the relationship between intracellular ammonium concentration and pigment production using glutamine as a nitrogen source. The intracellular ammonium level decreased about 1.5-fold in conditions favoring PP-V production. Moreover, P. purpurogenum was transferred to medium in which it commonly produces the related pigment PP-O after cultivating it in the presence or absence of glutamine to investigate whether this fungus biosynthesizes PP-V using surplus ammonium in cells. Only mycelia cultured in medium containing 10 mM glutamine produced the violet pigment, and simultaneously intracellular ammonium levels decreased under this condition. From comparisons of the amount of PP-V that was secreted with quantity of surplus intracellular ammonium, it is suggested that P. purpurogenum maintains ammonium homeostasis by excreting waste ammonium as PP-V.

  7. Analysis of ancient pigments by Raman microscopy

    International Nuclear Information System (INIS)

    Zuo Jian; Xu Cunyi

    1999-01-01

    Raman microscopy can be applied for the spatial resolution, and non-destructive in situ analysis of inorganic pigments in pottery, manuscripts and paintings. Compared with other techniques, it is the best single technique for this purpose. An overview is presented of the applications of Raman microscopy in the analysis of ancient pigments

  8. Thin Layer Chromatography (TLC) of Chlorophyll Pigments.

    Science.gov (United States)

    Foote, Jerry

    1984-01-01

    Background information, list of materials needed, procedures used, and discussion of typical results are provided for an experiment on the thin layer chromatography of chlorophyll pigments. The experiment works well in high school, since the chemicals used are the same as those used in paper chromatography of plant pigments. (JN)

  9. 21 CFR 178.3725 - Pigment dispersants.

    Science.gov (United States)

    2010-04-01

    ... HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: ADJUVANTS, PRODUCTION AIDS, AND SANITIZERS Certain Adjuvants and Production Aids § 178.3725 Pigment dispersants. Subject to the provisions of this... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Pigment dispersants. 178.3725 Section 178.3725 Food...

  10. Quantifying Abdominal Pigmentation in Drosophila melanogaster.

    Science.gov (United States)

    Saleh Ziabari, Omid; Shingleton, Alexander W

    2017-06-01

    Pigmentation is a morphologically simple but highly variable trait that often has adaptive significance. It has served extensively as a model for understanding the development and evolution of morphological phenotypes. Abdominal pigmentation in Drosophila melanogaster has been particularly useful, allowing researchers to identify the loci that underlie inter- and intraspecific variations in morphology. Hitherto, however, D. melanogaster abdominal pigmentation has been largely assayed qualitatively, through scoring, rather than quantitatively, which limits the forms of statistical analysis that can be applied to pigmentation data. This work describes a new methodology that allows for the quantification of various aspects of the abdominal pigmentation pattern of adult D. melanogaster. The protocol includes specimen mounting, image capture, data extraction, and analysis. All the software used for image capture and analysis feature macros written for open-source image analysis. The advantage of this approach is the ability to precisely measure pigmentation traits using a methodology that is highly reproducible across different imaging systems. While the technique has been used to measure variation in the tergal pigmentation patterns of adult D. melanogaster, the methodology is flexible and broadly applicable to pigmentation patterns in myriad different organisms.

  11. Pigmented skin disorders: Evaluation and treatment

    NARCIS (Netherlands)

    Kroon, M.W.

    2015-01-01

    Pigmentary disorders are disturbances of human skin color. Minor changes in the cellular physiology of the skin can dramatically affect pigment production in positive or negative manner. In this these, associated diseases, therapeutical options and disease parameters for the pigmentation disorder

  12. A Model for Interpreting High-Tower CO2 Concentration Records for the Surface Carbon Balance Information

    Science.gov (United States)

    Chen, B.; Chen, J. M.; Higuchi, K.; Chan, D.; Shashkov, A.

    2002-05-01

    Atmospheric CO2 concentration measurements have been made by scientists of Meteorological Service of Canada on a 40 m tower for the last 10 years at 15 minute intervals over a mostly intact boreal forest near Fraserdale (50N, 81W), Ontario, Canada. The long time records of CO2 as well as basic meteorological variables provide a unique opportunity to investigate any potential changes in the ecosystem in terms of carbon balance. A model is needed to decipher the carbon cycle signals from the diurnal and seasonal variation patterns in the CO2 record. For this purpose, the Boreal Ecosystem Productivity Simulator (BEPS) is expanded to include a one-dimensional CO2 vertical transfer model involving the interaction between plant canopies and the atmosphere in the surface layer and the diurnal dynamics of the mixed layer. An analytical solution of the scalar transfer equation within the surface layer is found using an assumption that the diurnal oscillation of CO2 concentration at a given height is sinusoidal, which is suitable for the investigation of the changes in diurnal variation pattern over the 10 year period. The complex interactions between the daily cycle of the atmosphere and vegetation CO2 exchange and the daily evolution of mixed layer entrainment of CO2 determines the CO2 variation pattern at a given height. The expanded BEPS can simulate within ñ2 ppm the hourly CO2 records at the 40 m measurement height. The annual totals of gross primary productivity (GPP), net primary productivity (NPP) and net ecosystem productivity (NEP), summed up from the hourly results, agree within 5% of previous estimates of BEPS at daily steps, indicating the internal consistency of the hourly model. The model is therefore ready for exploring changes in the CO2 record as affected by changes in the forest ecosystems upwind of the tower. Preliminary results indicate that the diurnal variation amplitude of CO2 has increased by 10-20% over the 10 years period, and this change can

  13. Rinsing paired-agent model (RPAM) to quantify cell-surface receptor concentrations in topical staining applications of thick tissues

    Science.gov (United States)

    Xu, Xiaochun; Wang, Yu; Xiang, Jialing; Liu, Jonathan T. C.; Tichauer, Kenneth M.

    2017-06-01

    Conventional molecular assessment of tissue through histology, if adapted to fresh thicker samples, has the potential to enhance cancer detection in surgical margins and monitoring of 3D cell culture molecular environments. However, in thicker samples, substantial background staining is common despite repeated rinsing, which can significantly reduce image contrast. Recently, ‘paired-agent’ methods—which employ co-administration of a control (untargeted) imaging agent—have been applied to thick-sample staining applications to account for background staining. To date, these methods have included (1) a simple ratiometric method that is relatively insensitive to noise in the data but has accuracy that is dependent on the staining protocol and the characteristics of the sample; and (2) a complex paired-agent kinetic modeling method that is more accurate but is more noise-sensitive and requires a precise serial rinsing protocol. Here, a new simplified mathematical model—the rinsing paired-agent model (RPAM)—is derived and tested that offers a good balance between the previous models, is adaptable to arbitrary rinsing-imaging protocols, and does not require calibration of the imaging system. RPAM is evaluated against previous models and is validated by comparison to estimated concentrations of targeted biomarkers on the surface of 3D cell culture and tumor xenograft models. This work supports the use of RPAM as a preferable model to quantitatively analyze targeted biomarker concentrations in topically stained thick tissues, as it was found to match the accuracy of the complex paired-agent kinetic model while retaining the low noise-sensitivity characteristics of the ratiometric method.

  14. Synthesis and Characterization of Nanosized Fe2O3 Pigments

    Directory of Open Access Journals (Sweden)

    M. F. R. Fouda

    2012-01-01

    Full Text Available The work in this paper was devoted to investigating some nanosized iron oxide pigments prepared by microemulsion technique. The role of concentration of iron salt and surfactant (cetyltrimethylammonium bromide on the produced iron oxide was studied. The techniques employed to characterize the samples were thermogravimetric analysis, X-ray diffractometry, transmission electron microscope, infrared spectroscopy, and diffuse reflectance spectroscopy. The results revealed that the particle size of the prepared sample using 0.2 M iron sulfate and 3.2 wt% of surfactant was in the range 7–9 nm. Increasing the concentration of either iron salt or the surfactant increased the particle size of the obtained ferric oxide. The diffuse reflectance measurements showed that the charge transfer/electron pair transition absorption peak, which is closely related to the reddish color of the oxide, was shifted to a longer wavelength (blue shift by decreasing the dimension of the particles. The samples were tested as pigments. They showed different tints of red color and were found to be promising for applications as pigments in the field of paint manufacturing.

  15. Bilateral pigmented villonodular synovitis of the knee

    Directory of Open Access Journals (Sweden)

    Samir H. Shah

    2015-12-01

    Full Text Available Pigmented villonodular synovitis is a disorder resulting in a villous, nodular, or villonodular proliferation of the synovium, with pigmentation related to the presence of hemosiderin. These lesions are almost exclusively benign with rare reports of malignancy. Pigmented villonodular synovitis can occur in a variety of joints and at any age but most often occurs within the knee in the young adult. Pigmented villonodular synovitis is a rare disease entity, and bilateral synchronous or metachronous involvement of a joint is even more uncommon, with few reports previously described in the literature. We present a case of pigmented villonodular synovitis involving both the right and left knee in the same patient, with radiographic imaging, magnetic resonance imaging, photograph and video intraoperative imaging, and pathologic correlation.

  16. Visualizing and simulating flow conditions in concrete form filling using pigments

    DEFF Research Database (Denmark)

    Jacobsen, Stefan; Cepuritis, Rolands; Peng, Ya

    2013-01-01

    Flow variation at surfaces and reinforcement during form filling was visualized with grey and black SCC. The border between grey and black (pigmented) SCC was captured as frozen images on hardened sawn- and formwork surfaces in a flow box experiment. Maximum velocity occurred at the centre...... of the closed box, and lowest velocity near the formwork, particularly with reinforcement parallel to formwork. Smooth formwork gave shorter flow profiles (higher surface velocity) than rough formwork. The pigmented mixes had similar workability though somewhat increased yield stress. Flow pattern depended...

  17. Study of Biological Pigments by Single Specimen Derivative Spectrophotometry

    Science.gov (United States)

    Goldstein, Jack M.

    1970-01-01

    The single specimen derivative (SSD) method provides an absolute absorption spectrum of a substance in the absence of a suitable reference. Both a reference and a measuring monochromatic beam pass through a single sample, and the specimen itself acts as its own reference. The two monochromatic beams maintain a fixed wavelength difference upon scanning, and the difference in absorbance of the two beams is determined. Thus, the resulting spectrum represents the first derivative of the conventional type absorption spectrum. Tissues and cell fractions have been examined at room and liquid N2 temperature and chromophoric molecules such as the mitochondrial cytochromes and blood pigments have been detectable in low concentrations. In the case of isolated cellular components, the observed effects of substrates and inhibitors confirm similar studies by conventional spectrophotometry. The extension of the SSD concept to the microscopic level has permitted the study of the tissue compartmentalization and function of cytochromes and other pigments within layered tissue. PMID:4392452

  18. Red pigment-concentrating hormone is not limited to crustaceans

    Czech Academy of Sciences Publication Activity Database

    Gäde, G.; Auerswald, L.; Šimek, Petr; Marcoa, H. G.; Kodrík, Dalibor

    2003-01-01

    Roč. 309, - (2003), s. 967-973 ISSN 0006-291X R&D Projects: GA AV ČR IPP1050128; GA AV ČR IAA6007202 Institutional research plan: CEZ:AV0Z5007907 Keywords : Arthropods * Crustaceans * insects Subject RIV: ED - Physiology Impact factor: 2.836, year: 2003

  19. An investigation of multispectral imaging for the mapping of pigments in paintings

    Science.gov (United States)

    Zhao, Yonghui; Berns, Roy S.; Taplin, Lawrence A.; Coddington, James

    2008-02-01

    Compared with colorimetric imaging, multispectral imaging has the advantage of retrieving spectral reflectance factor of each pixel of a painting. Using this spectral information, pigment mapping is concerned with decomposing the spectrum into its constituent pigments and their relative contributions. The output of pigment mapping is a series of spatial concentration maps of the pigments comprising the painting. This approach was used to study Vincent van Gogh's The Starry Night. The artist's palette was approximated using ten oil pigments, selected from a large database of pigments used in oil paintings and a priori analytical research on one of his self portraits, executed during the same time period. The pigment mapping was based on single-constant Kubelka-Munk theory. It was found that the region of blue sky where the stars were located contained, predominantly, ultramarine blue while the swirling sky and region surrounding the moon contained, predominantly, cobalt blue. Emerald green, used in light bluish-green brushstrokes surrounding the moon, was not used to create the dark green in the cypresses. A measurement of lead white from Georges Seurat's La Grande Jatte was used as the white when mapping The Starry Night. The absorption and scattering properties of this white were replaced with a modern dispersion of lead white in linseed oil and used to simulate the painting's appearance before the natural darkening and yellowing of lead white oil paint. Pigment mapping based on spectral imaging was found to be a viable and practical approach for analyzing pigment composition, providing new insight into an artist's working method, the possibility for aiding in restorative inpainting, and lighting design.

  20. Structure of plant bile pigments

    Energy Technology Data Exchange (ETDEWEB)

    Schoenleber, R.W.

    1983-12-01

    Selective peptide cleavage has provided a general procedure for the study of the structure, including stereochemistry, of plant bile pigments. The information derived from the synthesis and spectral analysis of a series of 2,3-dihydrodioxobilins allows the determination of the trans relative stereochemistry for ring A of the ..beta../sub 1/-phycocyanobilin from C-phycocyanin as well as for ring A of phytochrome. A complete structure proof of the five phycoerythrobilins attached to the ..cap alpha.. and ..beta.. subunits of B-phycoerythrin is described. One of these tetrapyrroles is doubly-peptide linked to a single peptide chain through two thioethers at the C-3' and C-18' positions. The four remaining phycoerythrobilins are singly-linked to the protein through thioethers at the C-3' position and all possess the probable stereochemistry C-2(R), C-3(R), C-3'(R), and C-16(R).

  1. Manipulation of lipoplex concentration at the cell surface boosts transfection efficiency in hard-to-transfect cells.

    Science.gov (United States)

    Palchetti, Sara; Pozzi, Daniela; Marchini, Cristina; Amici, Augusto; Andreani, Cristina; Bartolacci, Caterina; Digiacomo, Luca; Gambini, Valentina; Cardarelli, Francesco; Di Rienzo, Carmine; Peruzzi, Giovanna; Amenitsch, Heinz; Palermo, Rocco; Screpanti, Isabella; Caracciolo, Giulio

    2017-02-01

    To date, efficiency upon non-viral DNA delivery remains low and this implies the existence of unidentified transfection barriers. Here we explore the mechanisms of action of multicomponent (MC) cationic liposome/DNA complexes (lipoplexes) by a combination of reporter technologies, dynamic light scattering (DLS), synchrotron small angle X-ray scattering (SAXS), fluorescence activated cell sorting (FACS) analysis and laser scanning confocal microscopy (LSCM) in live cells. Lipofectamine - the gold standard among transfection reagents - was used as a reference. On the basis of our results, we suggest that an additional transfection barrier impairs transfection efficiency, that is: low lipoplex concentration at the cell surface. Based on the acquired knowledge we propose an optimized transfection protocol that allowed us to efficiently transfect DND41, JURKAT, MOLT3, P12-ICHIKAWA, ALL-SILL, TALL-1 human T-cell acute lymphoblastic leukemia (T-ALL) cell lines known to be difficult-to-transfect by using non-viral vectors and where LFN-based technologies fail to give satisfactory results. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Transport processes associated with the initial elevated concentrations of Chernobyl radioactivity in surface air in the United States

    International Nuclear Information System (INIS)

    Larsen, R.J.; Haagenson, P.L.; Reiss, N.M.

    1989-01-01

    Elevated concentrations of radioactivity from the Chernobyl accident were encountered in the surface air over the United States along the east coast and in the north-west on 9 and 10 May 1986. The nearly simultaneous arrival of radioactive debris at widely separated locations resulted from different paths being taken by the debris released at different times during the course of the accident. Debris released during the explosion at the Chernobyl reactor was transported across the Arctic, within the lower troposphere, and zonally across Asia and the North Pacific Ocean, within the mid-troposphere. This debris descended into the planetary boundary layer along the east coast of the US. The descent was associated with a quasi-stationary cyclone located over the western North Atlantic Ocean. Debris that had a different composition of radioactivity was released from the damaged reactor during the week immediately following the initial explosion. This debris was then transported zonally across Asia and the North Pacific Ocean within the planetary boundary layer and lower troposphere and was swept into the north-western US. (author)

  3. Heavy metals concentrations of surface dust from e-waste recycling and its human health implications in southeast China.

    Science.gov (United States)

    Leung, Anna O W; Duzgoren-Aydin, Nurdan S; Cheung, K C; Wong, Ming H

    2008-04-01

    The recycling of printed circuit boards in Guiyu, China, a village intensely involved in e-waste processing, may present a significant environmental and human health risk. To evaluate the extent of heavy metals (Cd, Co, Cr, Cu, Ni, Pb, Zn) contamination from printed circuit board recycling, surface dust samples were collected from recycling workshops, adjacent roads, a schoolyard, and an outdoor food market. ICP-OES analyses revealed elevated mean concentrations in workshop dust (Pb 110,000, Cu 8360, Zn 4420, and Ni 1500 mg/kg) and in dust of adjacent roads (Pb 22,600, Cu 6170, Zn 2370, and Ni 304 mg/kg). Lead and Cu in road dust were 330 and 106, and 371 and 155 times higher, respectively, than non e-waste sites located 8 and 30 km away. Levels at the schoolyard and food market showed that public places were adversely impacted. Risk assessment predicted that Pb and Cu originating from circuit board recycling have the potential to pose serious health risks to workers and local residents of Guiyu, especially children, and warrants an urgent investigation into heavy metal related health impacts. The potential environmental and human health consequences due to uncontrolled e-waste recycling in Guiyu serves as a case study for other countries involved in similar crude recycling activities.

  4. Radiation Stability of Zinc Oxide Pigment Modified by Zirconium Oxide and Aluminum Oxide Nanopowders

    International Nuclear Information System (INIS)

    Mikhailov, M. M.; Neshchimenko, V. V.; Li Chundong

    2009-01-01

    The effect on the reflective spectra of heat treatment and modification of ZnO pigments by 1-30 wt.%ZrO 2 and Al 2 O 3 nanoparticles has been investigated before and after irradiation by 100 keV protons with a fluence of 5x10 15 cm -2 . It is established that with the optimum concentration of 5 wt.% nanoparticles and the temperature of 800 deg. C a 20% increase in the radiation stability is observed for the modified ZnO pigment in comparison with the not modified pigment. The decrease of absorption in the modified pigments is determined by the decrease of the intensity of the absorption bands of the zinc vacancies (V zn - ), oxygen vacancies (V o + ) and donor-acceptor couples (V zn - - Zn i 0 ).

  5. Fungal and Bacterial Pigments: Secondary Metabolites with Wide Applications

    Science.gov (United States)

    Narsing Rao, Manik Prabhu; Xiao, Min; Li, Wen-Jun

    2017-01-01

    The demand for natural colors is increasing day by day due to harmful effects of some synthetic dyes. Bacterial and fungal pigments provide a readily available alternative source of naturally derived pigments. In contrast to other natural pigments, they have enormous advantages including rapid growth, easy processing, and independence of weather conditions. Apart from colorant, bacterial and fungal pigments possess many biological properties such as antioxidant, antimicrobial and anticancer activity. This review outlines different types of pigments. It lists some bacterial and fungal pigments and current bacterial and fungal pigment status and challenges. It also focuses on possible fungal and bacterial pigment applications. PMID:28690593

  6. Fungal and Bacterial Pigments: Secondary Metabolites with Wide Applications

    Directory of Open Access Journals (Sweden)

    Manik Prabhu Narsing Rao

    2017-06-01

    Full Text Available The demand for natural colors is increasing day by day due to harmful effects of some synthetic dyes. Bacterial and fungal pigments provide a readily available alternative source of naturally derived pigments. In contrast to other natural pigments, they have enormous advantages including rapid growth, easy processing, and independence of weather conditions. Apart from colorant, bacterial and fungal pigments possess many biological properties such as antioxidant, antimicrobial and anticancer activity. This review outlines different types of pigments. It lists some bacterial and fungal pigments and current bacterial and fungal pigment status and challenges. It also focuses on possible fungal and bacterial pigment applications.

  7. Utilization and optimization of a waste stream cellulose culture medium for pigment production by Penicillium spp.

    Science.gov (United States)

    Sopandi, T; Wardah, A; Surtiningsih, T; Suwandi, A; Smith, J J

    2013-03-01

    This research sought to determine optimal corn waste stream-based fermentation medium C and N sources and incubation time to maximize pigment production by an indigenous Indonesian Penicillium spp., as well as to assess pigment pH stability. A Penicillium spp. was isolated from Indonesian soil, identified as Penicillium resticulosum, and used to test the effects of carbon and nitrogen type and concentrations, medium pH, incubation period and furfural on biomass and pigment yield (PY) in a waste corncob hydrolysate basal medium. Maximum red PY (497.03 ± 55.13 mg l(-1)) was obtained with a 21 : 1 C : N ratio, pH 5.5-6.0; yeast extract-, NH(4) NO(3)-, NaNO(3)-, MgSO(4) ·7H(2) O-, xylose- or carboxymethylcellulose (CMC)-supplemented medium and 12 days (25 °C, 60-70% relative humidity, dark) incubation. C source, C, N and furfural concentration, medium pH and incubation period all influenced biomass and PY. Pigment was pH 2-9 stable. Penicillium resticulosum demonstrated microbial pH-stable-pigment production potential using a xylose or CMC and N source, supplemented waste stream cellulose culture medium. Corn derived, waste stream cellulose can be used as a culture medium for fungal pigment production. Such application provides a process for agricultural waste stream resource reuse for production of compounds in increasing demand. © 2012 The Society for Applied Microbiology.

  8. Sedimentary pigments and nature of organic matter within the oxygen minimum zone (OMZ) of the Eastern Arabian Sea (Indian margin)

    Digital Repository Service at National Institute of Oceanography (India)

    Rasiq, K.T.; Kurian, S.; Karapurkar, S.G.; Naqvi, S.W.A.