Science.gov

Sample records for accumulated higher concentrations

  1. Passive CO2 concentration in higher plants.

    PubMed

    Sage, Rowan F; Khoshravesh, Roxana

    2016-06-01

    Photorespiratory limitations on C3 photosynthesis are substantial in warm, low CO2 conditions. To compensate, certain plants evolved mechanisms to actively concentrate CO2 around Rubisco using ATP-supported CO2 pumps such as C4 photosynthesis. Plants can also passively accumulate CO2 without additional ATP expenditure by localizing the release of photorespired and respired CO2 around Rubisco that is diffusively isolated from peripheral air spaces. Passive accumulation of photorespired CO2 occurs when glycine decarboxylase is localized to vascular sheath cells in what is termed C2 photosynthesis, and through forming sheaths of chloroplasts around the periphery of mesophyll cells. The peripheral sheaths require photorespired CO2 to re-enter chloroplasts where it can be refixed. Passive accumulation of respiratory CO2 is common in organs such as stems, fruits and flowers, due to abundant heterotrophic tissues and high diffusive resistance along the organ periphery. Chloroplasts within these organs are able to exploit this high CO2 to reduce photorespiration. CO2 concentration can also be enhanced passively by channeling respired CO2 from roots and rhizomes into photosynthetic cells of stems and leaves via lacunae, aerenchyma and the xylem stream. Through passive CO2 concentration, C3 species likely improved their carbon economy and maintained fitness during episodes of low atmospheric CO2.

  2. Characters related to higher starch accumulation in cassava storage roots

    PubMed Central

    Li, You-Zhi; Zhao, Jian-Yu; Wu, San-Min; Fan, Xian-Wei; Luo, Xing-Lu; Chen, Bao-Shan

    2016-01-01

    Cassava (Manihot esculenta) is valued mainly for high content starch in its roots. Our understanding of mechanisms promoting high starch accumulation in the roots is, however, still very limited. Two field-grown cassava cultivars, Huanan 124(H124) with low root starch and Fuxuan 01(F01) with high root starch, were characterised comparatively at four main growth stages. Changes in key sugars in the leaves, stems and roots seemed not to be strongly associated with the final amount of starch accumulated in the roots. However, when compared with H124, F01 exhibited a more compact arrangement of xylem vascular bundles in the leaf axils, much less callose around the phloem sieve plates in the stems, higher starch synthesis-related enzymatic activity but lower amylase activity in the roots, more significantly up-regulated expression of related genes, and a much higher stem flow rate (SFR). In conclusion, higher starch accumulation in the roots results from the concurrent effects of powerful stem transport capacity highlighted by higher SFR, high starch synthesis but low starch degradation in the roots, and high expression of sugar transporter genes in the stems. A model of high starch accumulation in cassava roots was therefore proposed and discussed. PMID:26892156

  3. Characters related to higher starch accumulation in cassava storage roots.

    PubMed

    Li, You-Zhi; Zhao, Jian-Yu; Wu, San-Min; Fan, Xian-Wei; Luo, Xing-Lu; Chen, Bao-Shan

    2016-02-19

    Cassava (Manihot esculenta) is valued mainly for high content starch in its roots. Our understanding of mechanisms promoting high starch accumulation in the roots is, however, still very limited. Two field-grown cassava cultivars, Huanan 124(H124) with low root starch and Fuxuan 01(F01) with high root starch, were characterised comparatively at four main growth stages. Changes in key sugars in the leaves, stems and roots seemed not to be strongly associated with the final amount of starch accumulated in the roots. However, when compared with H124, F01 exhibited a more compact arrangement of xylem vascular bundles in the leaf axils, much less callose around the phloem sieve plates in the stems, higher starch synthesis-related enzymatic activity but lower amylase activity in the roots, more significantly up-regulated expression of related genes, and a much higher stem flow rate (SFR). In conclusion, higher starch accumulation in the roots results from the concurrent effects of powerful stem transport capacity highlighted by higher SFR, high starch synthesis but low starch degradation in the roots, and high expression of sugar transporter genes in the stems. A model of high starch accumulation in cassava roots was therefore proposed and discussed.

  4. Metal accumulation and toxicity: the critical accumulated concentration of metabolically available zinc in an oyster model.

    PubMed

    Rainbow, Philip S; Liu, Fengjie; Wang, Wen-Xiong

    2015-05-01

    Invertebrates typically carry out detoxification of accumulated metals. There is, therefore, no threshold total body concentration of accumulated metal initiating toxicity, the onset of toxic effects rather being related to a critical concentration of metabolically available (MA) accumulated metal. The challenge remains as to whether any particular combination of subcellular fractions of accumulated metal can be identified to represent this theoretical MA component. One candidate combined fraction is the so-termed metal sensitive fraction (MSF), consisting of metal bound to organelles and non-detoxificatory soluble proteins. In this study, we used laboratory zinc accumulation and toxicity data for four populations of the oyster Crassostrea hongkongensis with different histories of zinc exposure in the field to address the challenge. We conclude that in a 'control' population of the oyster, the MSF does approximate to the theoretical metabolically available zinc concentration. In populations with a history of field exposure to raised zinc bioavailabilities, however, the MSF would include more zinc detoxified in the lysosome component of organelle-bound metal, and the MSF in such populations would deviate more from the theoretical MA metal concentration.

  5. Cast Stone Formulation At Higher Sodium Concentrations

    SciTech Connect

    Fox, K. M.; Edwards, T. A.; Roberts, K. B.

    2013-10-02

    concentration in the salt solution reduced the time to peak heat flow, and reducing the amount of slag in the premix increased the time to peak heat flow. These observations may help to describe some of the cured properties of the samples, in particular the differences in compressive strength observed after 28 and 90 days of curing. Samples were cured for at least 28 days at ambient temperature in the laboratory prior to cured properties analyses. The low activity waste form for disposal at the Hanford Site is required to have a compressive strength of at least 500 psi. After 28 days of curing, several of the test mixes had mean compressive strengths that were below the 500 psi requirement. Higher sodium concentrations and higher water to premix ratios led to reduced compressive strength. Higher fly ash concentrations decreased the compressive strength after 28 days of curing. This may be explained in that the cementitious phases matured more quickly in the mixes with higher concentrations of slag, as evidenced by the data for the time to peak heat generation. All of the test mixes exhibited higher mean compressive strengths after 90 days of curing, with only one composition having a mean compressive strength of less than 500 psi. Leach indices were determined for the test mixes for contaminants of interest. The leaching performance of the mixes evaluated in this study was not particularly sensitive to the factors used in the experimental design. This may be beneficial in demonstrating that the performance of the waste form is robust with respect to changes in the mix composition. The results of this study demonstrate the potential to achieve significantly higher waste loadings in Cast Stone and other low temperature, cementitious waste forms. Additional work is needed to elucidate the hydration mechanisms occurring in Cast Stone formulated with highly concentrated salt solutions since these reactions are responsible for determining the performance of the cured waste form. The

  6. Cast Stone Formulation At Higher Sodium Concentrations

    SciTech Connect

    Fox, K. M.; Roberts, K. A.; Edwards, T. B.

    2014-02-28

    concentration in the salt solution reduced the time to peak heat flow, and reducing the amount of slag in the premix increased the time to peak heat flow. These observations may help to describe some of the cured properties of the samples, in particular the differences in compressive strength observed after 28 and 90 days of curing. Samples were cured for at least 28 days at ambient temperature in the laboratory prior to cured properties analyses. The low activity waste form for disposal at the Hanford Site is required to have a compressive strength of at least 500 psi. After 28 days of curing, several of the test mixes had mean compressive strengths that were below the 500 psi requirement. Higher sodium concentrations and higher water to premix ratios led to reduced compressive strength. Higher fly ash concentrations decreased the compressive strength after 28 days of curing. This may be explained in that the cementitious phases matured more quickly in the mixes with higher concentrations of slag, as evidenced by the data for the time to peak heat generation. All of the test mixes exhibited higher mean compressive strengths after 90 days of curing, with only one composition having a mean compressive strength of less than 500 psi. Leachability indices were determined for the test mixes for contaminants of interest. The leaching performance of the mixes evaluated in this study was not particularly sensitive to the factors used in the experimental design. This may be beneficial in demonstrating that the performance of the waste form is robust with respect to changes in the mix composition. The results of this study demonstrate the potential to achieve significantly higher waste loadings in Cast Stone and other low temperature, cementitious waste forms. Additional work is needed to elucidate the hydration mechanisms occurring in Cast Stone formulated with highly concentrated salt solutions since these reactions are responsible for determining the performance of the cured waste

  7. Cast Stone Formulation At Higher Sodium Concentrations

    SciTech Connect

    Fox, K. M.; Roberts, K. A.; Edwards, T. B.

    2013-09-17

    concentration in the salt solution reduced the time to peak heat flow, and reducing the amount of slag in the premix increased the time to peak heat flow. These observations may help to describe some of the cured properties of the samples, in particular the differences in compressive strength observed after 28 and 90 days of curing. Samples were cured for at least 28 days at ambient temperature in the laboratory prior to cured properties analyses. The low activity waste form for disposal at the Hanford Site is required to have a compressive strength of at least 500 psi. After 28 days of curing, several of the test mixes had mean compressive strengths that were below the 500 psi requirement. Higher sodium concentrations and higher water to premix ratios led to reduced compressive strength. Higher fly ash concentrations decreased the compressive strength after 28 days of curing. This may be explained in that the cementitious phases matured more quickly in the mixes with higher concentrations of slag, as evidenced by the data for the time to peak heat generation. All of the test mixes exhibited higher mean compressive strengths after 90 days of curing, with only one composition having a mean compressive strength of less than 500 psi. Leach indices were determined for the test mixes for contaminants of interest. The leaching performance of the mixes evaluated in this study was not particularly sensitive to the factors used in the experimental design. This may be beneficial in demonstrating that the performance of the waste form is robust with respect to changes in the mix composition. The results of this study demonstrate the potential to achieve significantly higher waste loadings in Cast Stone and other low temperature, cementitious waste forms. Additional work is needed to elucidate the hydration mechanisms occurring in Cast Stone formulated with highly concentrated salt solutions since these reactions are responsible for determining the performance of the cured waste form. The

  8. Cadmium speciation and accumulation in periphyton in a small stream with dynamic concentration variations.

    PubMed

    Bradac, Philippe; Wagner, Bettina; Kistler, David; Traber, Jacqueline; Behra, Renata; Sigg, Laura

    2010-03-01

    Accumulation of cadmium in periphyton was investigated under field conditions while Cd concentration and speciation were dynamically varying in a small stream during rain events. Speciation in water was determined in situ by diffusion gradient in thin-films (DGT) and by modeling of complexation with fulvic acids. During the rain events, dissolved Cd concentrations increased from 0.17 nM to 0.27-0.36 nM, and 70-97% were DGT-labile. Cd content in periphyton closely followed Cd concentrations in water, despite higher concentrations of Zn and Mn, and may be controlled by either free or DGT-labile Cd concentrations. Decrease of Cd content in periphyton after the rain events was slower than the decrease of Cd concentration in water. Concentrations of Zn, Mn, Cu, Pb and Fe in periphyton also followed the dynamic variations of metal concentrations in water. Repeated exposure of periphyton to elevated dissolved Cd may lead to Cd accumulation.

  9. Concentration is not enough to evaluate accumulation of heavy metals and nutrients in plants.

    PubMed

    Vymazal, Jan

    2016-02-15

    Wetland plants produce high aboveground biomass and possess the ability to accumulate heavy metals and nutrients. This ability is used for phytoremediation purposes including removal of nutrients and heavy metals from polluted waters. The concentrations of heavy metals are usually much higher in the belowground then in aboveground biomass, especially in roots which are primary sites of uptake. This may lead to the conclusion that accumulation of heavy metals is higher in the belowground biomass. However, in case the aboveground is much higher than belowground biomass the accumulation could be higher in the aboveground biomass. Concentration of nitrogen and phosphorus is always higher in leaves than in stems. However, the stem biomass is often much higher in robust emergent species such as Phragmites australis and therefore, more nutrients can be stored in stems. The examples shown in this communication clearly reveal that to evaluate properly the accumulation of heavy metals and nutrients in particular plant compartment biomass amount must be taken into consideration. In the first study, concentrations of Cd, Cr and Hg in Phalaris arundinacea belowground/aboveground biomass were 150/80 μg/kg, 5420/228 μg/kg and 38/18 μg/kg. The high aboveground biomass (1196 g/m(2)) and low belowground biomass (244 g/(2)) resulted in much higher accumulation of Cd and Hg in aboveground biomass (96 μg/m(2) and 21.2 μg/m(2), respectively) than in belowground biomass (36 μg/m(2) and 9.3 μg/m(2), respectively). Only for chromium, belowground accumulation (1312 μg/m(2)) was higher than aboveground accumulation (272 μg/m(2)). In the second study, both nitrogen and phosphorus concentrations were higher (26.7 mg/g and 749 mg/kg, respectively) in leaves than in stems (8.2mg/g and 534 mg/kg, respectively) of P. australis. The higher biomass of stems (1835 g/m(2)) than leaves (967 g/m(2)) resulted in higher accumulation of nitrogen but lower accumulation of phosphorus in leaves as

  10. Intracellular accumulation of boceprevir according to plasma concentrations and pharmacogenetics.

    PubMed

    Cusato, Jessica; Allegra, Sarah; De Nicolò, Amedeo; Boglione, Lucio; Fatiguso, Giovanna; Abdi, Adnan Mohamed; Cariti, Giuseppe; Di Perri, Giovanni; D'Avolio, Antonio

    2015-06-01

    Boceprevir (BOC) is a directly-acting antiviral agent for the treatment of hepatitis C virus genotype 1 (HCV-1) infection. It is a mixture of two stereoisomers, the inactive R and the active S isomers. No data have previously been published on BOC intracellular accumulation. In this study, BOC isomer concentrations in peripheral blood mononuclear cells (PBMCs) and plasma were determined. The influence of various single nucleotide polymorphisms (SNPs) on plasma and intracellular drug exposure at Week 4 of triple therapy were also evaluated. Plasma and intracellular BOC concentrations were determined at the end of the dosing interval (C(trough)) using a UPLC-MS/MS validated method. Allelic discrimination was performed through real-time PCR. Median plasma concentrations were 65.97 ng/mL for the S isomer and 36.31 ng/mL for the R isomer; the median S/R plasma concentration ratio was 1.66. The median PBMC concentration was 2285.88 ng/mL for the S isomer; the R isomer was undetectable within PBMCs. The median S isomer PBMC/plasma concentration ratio was 28.59. A significant positive correlation was found between plasma and PBMC S isomer concentrations. ABCB1 1236, SLC28A2 124 and IL28B rs12979860 SNPs were associated with the S isomer PBMC/plasma concentration ratio. In regression models, S isomer plasma levels and FokI polymorphism were able to predict S isomer intracellular exposure, whereas SNPs in AKR1, BCRP1 and SLC28A2 predicted the S isomer PBMC/plasma concentration ratio. No similar data regarding BOC pharmacogenetics and pharmacokinetics have been published previously. This study adds a novel and useful overview of the pharmacological properties of this drug. PMID:25836019

  11. Intracellular accumulation of boceprevir according to plasma concentrations and pharmacogenetics.

    PubMed

    Cusato, Jessica; Allegra, Sarah; De Nicolò, Amedeo; Boglione, Lucio; Fatiguso, Giovanna; Abdi, Adnan Mohamed; Cariti, Giuseppe; Di Perri, Giovanni; D'Avolio, Antonio

    2015-06-01

    Boceprevir (BOC) is a directly-acting antiviral agent for the treatment of hepatitis C virus genotype 1 (HCV-1) infection. It is a mixture of two stereoisomers, the inactive R and the active S isomers. No data have previously been published on BOC intracellular accumulation. In this study, BOC isomer concentrations in peripheral blood mononuclear cells (PBMCs) and plasma were determined. The influence of various single nucleotide polymorphisms (SNPs) on plasma and intracellular drug exposure at Week 4 of triple therapy were also evaluated. Plasma and intracellular BOC concentrations were determined at the end of the dosing interval (C(trough)) using a UPLC-MS/MS validated method. Allelic discrimination was performed through real-time PCR. Median plasma concentrations were 65.97 ng/mL for the S isomer and 36.31 ng/mL for the R isomer; the median S/R plasma concentration ratio was 1.66. The median PBMC concentration was 2285.88 ng/mL for the S isomer; the R isomer was undetectable within PBMCs. The median S isomer PBMC/plasma concentration ratio was 28.59. A significant positive correlation was found between plasma and PBMC S isomer concentrations. ABCB1 1236, SLC28A2 124 and IL28B rs12979860 SNPs were associated with the S isomer PBMC/plasma concentration ratio. In regression models, S isomer plasma levels and FokI polymorphism were able to predict S isomer intracellular exposure, whereas SNPs in AKR1, BCRP1 and SLC28A2 predicted the S isomer PBMC/plasma concentration ratio. No similar data regarding BOC pharmacogenetics and pharmacokinetics have been published previously. This study adds a novel and useful overview of the pharmacological properties of this drug.

  12. A comparative study of aluminium and nutrient concentrations in mistletoes on aluminium-accumulating and non-accumulating hosts.

    PubMed

    Scalon, M C; Haridasan, M; Franco, A C

    2013-09-01

    Mistletoes offer a unique model to study interactions among Al and nutrients in vascular plants, because they grow and reproduce on hosts with distinct Al uptake strategies. We investigated Al distribution and nutrient relations of mistletoes on Al-accumulating and non-accumulating hosts. We hypothesised that mistletoes would exhibit similar leaf nutrient and Al concentrations as their host plants, but a strong compartmentalisation of Al when growing on Al-accumulators. We measured concentrations of N, P, K, Ca, Mg, Cu, Fe, Mn, Zn in leaves and Al in leaves, seeds and branches of Phthirusa ovata and Psittacanthus robustus infecting Miconia albicans, an Al-accumulator, and Ph. ovata infecting Byrsonima verbascifolia, a non-Al-accumulator. High leaf concentrations of Al in Ph. ovata only occurred while parasitizing the Al-accumulating host; there was no accumulation in branches or seeds. In P. robustus, large concentrations of Al were found in leaves, branches and seeds. Mistletoe seed viability and leaf nutrient concentrations were not affected by Al accumulation. Passive uptake of Al, Ca, Mg, Mn and Cu in mistletoes was evidenced by significant correlations between mistletoes and host leaf concentrations, but not of N, P and K. Al was retranslocated to different plant organs in P. robustus, whereas it was mostly restricted to leaves in Ph. ovata. We suggest that Al might have some specific function in P. robustus, which only parasitizes Al-accumulator hosts, while the host generalist Ph. ovata can be considered a facultative Al-accumulator.

  13. Cadmium speciation and accumulation in periphyton in a small stream with dynamic concentration variations.

    PubMed

    Bradac, Philippe; Wagner, Bettina; Kistler, David; Traber, Jacqueline; Behra, Renata; Sigg, Laura

    2010-03-01

    Accumulation of cadmium in periphyton was investigated under field conditions while Cd concentration and speciation were dynamically varying in a small stream during rain events. Speciation in water was determined in situ by diffusion gradient in thin-films (DGT) and by modeling of complexation with fulvic acids. During the rain events, dissolved Cd concentrations increased from 0.17 nM to 0.27-0.36 nM, and 70-97% were DGT-labile. Cd content in periphyton closely followed Cd concentrations in water, despite higher concentrations of Zn and Mn, and may be controlled by either free or DGT-labile Cd concentrations. Decrease of Cd content in periphyton after the rain events was slower than the decrease of Cd concentration in water. Concentrations of Zn, Mn, Cu, Pb and Fe in periphyton also followed the dynamic variations of metal concentrations in water. Repeated exposure of periphyton to elevated dissolved Cd may lead to Cd accumulation. PMID:19913341

  14. Effects of water management on cadmium and arsenic accumulation and dimethylarsinic acid concentrations in Japanese rice.

    PubMed

    Arao, Tomohito; Kawasaki, Akira; Baba, Koji; Mori, Shinsuke; Matsumoto, Shingo

    2009-12-15

    Rice consumption is a major source of cadmium and arsenic for the population of Asia. We investigated the effects of water management in rice paddy on levels of cadmium and arsenic in Japanese rice grains. Flooding increased arsenic concentrations in rice grains, whereas aerobic treatment increased the concentration of cadmium. Flooding for 3 weeks before and after heading was most effective in reducing grain cadmium concentrations, but this treatment increased the arsenic concentration considerably, whereas aerobic treatment during the same period was effective in reducing arsenic concentrations but increased the cadmium concentration markedly. Flooding treatment after heading was found to be more effective than flooding treatment before heading in reducing rice grain cadmium without a concomitant increase in total arsenic levels, although it increased inorganic arsenic levels. Concentrations of dimethylarsinic acid (DMA) in grain were very low under aerobic conditions but increased under flooded conditions. DMA accounted for 3-52% of the total arsenic concentration in grain grown in soil with a lower arsenic concentration and 10-80% in soil with a higher arsenic concentration. A possible explanation for the accumulation of DMA in rice grains is that DMA translocates from shoots/roots to the grains more readily than does inorganic arsenic. PMID:20000530

  15. Potassium concentration effect on growth, gas exchange and mineral accumulation in potatoes

    NASA Technical Reports Server (NTRS)

    Cao, W.; Tibbitts, T. W.

    1991-01-01

    This study was conducted to evaluate the responses of potatoes to six K solution concentrations maintained with a flow-through nutrient film system. Potato plants were grown for 42 days in sloping shallow trays containing a 1 cm layer of quartz gravel with a continuous flow of 4 ml min-1 of nutrient solutions having K concentrations of 0.10, 0.55, 1.59, 3.16, 6.44, 9.77 meq L-1. Plant leaf area, total and tuber dry weights were reduced over 25% at 0.10 meq L-1 of K and over 17% at 9.77 meq L-1 of K compared to concentrations of 0.55, 1.59, 3.16 and 6.44 meq L-1 of K. Gas exchange measurements on leaflets in situ after 39 days of growth demonstrated no significant differences among different K treatments in CO2 assimilation rate, stomatal conductance, intercellular CO2 concentration, and transpiration. Further measurements made only on plants grown at 0.10, 1.59, 6.44 meq L-1 of K showed similar responses of CO2 assimilation rate to different intercellular CO2 concentrations. This suggested that the photosynthetic systems were not affected by different K nutrition. The leaves of plants accumulated about 60% less K at 0.10 meq L-1 of K than at higher K concentrations. However, Ca and Mg levels in the leaves were higher at 0.10 meq L-1 of K than at higher K concentrations. This indicates that low K nutrition not only reduced plant growth, but also affected nutrient balance between major cations.

  16. Higher transcription levels in ascorbic acid biosynthetic and recycling genes were associated with higher ascorbic acid accumulation in blueberry.

    PubMed

    Liu, Fenghong; Wang, Lei; Gu, Liang; Zhao, Wei; Su, Hongyan; Cheng, Xianhao

    2015-12-01

    In our preliminary study, the ripe fruits of two highbush blueberry (Vaccinium corymbosum L.) cultivars, cv 'Berkeley' and cv 'Bluecrop', were found to contain different levels of ascorbic acid. However, factors responsible for these differences are still unknown. In the present study, ascorbic acid content in fruits was compared with expression profiles of ascorbic acid biosynthetic and recycling genes between 'Bluecrop' and 'Berkeley' cultivars. The results indicated that the l-galactose pathway was the predominant route of ascorbic acid biosynthesis in blueberry fruits. Moreover, higher expression levels of the ascorbic acid biosynthetic genes GME, GGP, and GLDH, as well as the recycling genes MDHAR and DHAR, were associated with higher ascorbic acid content in 'Bluecrop' compared with 'Berkeley', which indicated that a higher efficiency ascorbic acid biosynthesis and regeneration was likely to be responsible for the higher ascorbic acid accumulation in 'Bluecrop'.

  17. Accumulating Human Capital While Increasing Educational Inequality: A Study on Higher Education Policy in China

    ERIC Educational Resources Information Center

    Chan, Wing Kit; Ngok, Kinglun

    2011-01-01

    Since 1999, the expansion of higher education has been viewed as an important step in accumulating human capital for China that was to gradually open its domestic sectors to the global market at a turbulent time at the turn of the century. Recent studies suggest that the improvement of human capital has succeeded in preparing China with a solid…

  18. Low acetate concentrations favor polyphosphate-accumulating organisms over glycogen-accumulating organisms in enhanced biological phosphorus removal from wastewater.

    PubMed

    Tu, Yunjie; Schuler, Andrew J

    2013-04-16

    Glycogen-accumulating organisms (GAOs) are thought to compete with polyphosphate-accumulating organisms (PAOs) in enhanced biological phosphorus removal (EBPR) wastewater treatment systems. A laboratory sequencing batch reactor (SBR) was operated for one year to test the hypothesis that PAOs have a competitive advantage at low acetate concentrations, with a focus on low pH conditions previously shown to favor GAOs. PAOs dominated the system under conventional SBR operation with rapid acetate addition (producing high in-reactor concentrations) and pH values of 7.4-8.4. GAOs dominated when the pH was decreased (6.4-7.0). Decreasing the acetate addition rate led to very low reactor acetate concentrations, and PAOs recovered, supporting the study hypothesis. When the acetate feed rate was increased, EBPR failed again. Dominant PAOs and GAOs were Candidatus Accumulibacter phosphatis and Defluviicoccus Cluster 2, respectively, according to fluorescent in situ hybridization and 454 pyrosequencing. Surprisingly, GAOs were not the immediate causes of PAO failures, based on functional and population measurements. Pyrosequencing results suggested Dechloromonas and Tetrasphaera spp. may have also been PAOs, and additional potential GAOs were also identified. Full-scale systems typically have lower in-reactor acetate concentrations than laboratory SBRs, and so, previous laboratory studies may have overestimated the practical importance of GAOs as causes of EBPR failure. PMID:23477409

  19. Low acetate concentrations favor polyphosphate-accumulating organisms over glycogen-accumulating organisms in enhanced biological phosphorus removal from wastewater.

    PubMed

    Tu, Yunjie; Schuler, Andrew J

    2013-04-16

    Glycogen-accumulating organisms (GAOs) are thought to compete with polyphosphate-accumulating organisms (PAOs) in enhanced biological phosphorus removal (EBPR) wastewater treatment systems. A laboratory sequencing batch reactor (SBR) was operated for one year to test the hypothesis that PAOs have a competitive advantage at low acetate concentrations, with a focus on low pH conditions previously shown to favor GAOs. PAOs dominated the system under conventional SBR operation with rapid acetate addition (producing high in-reactor concentrations) and pH values of 7.4-8.4. GAOs dominated when the pH was decreased (6.4-7.0). Decreasing the acetate addition rate led to very low reactor acetate concentrations, and PAOs recovered, supporting the study hypothesis. When the acetate feed rate was increased, EBPR failed again. Dominant PAOs and GAOs were Candidatus Accumulibacter phosphatis and Defluviicoccus Cluster 2, respectively, according to fluorescent in situ hybridization and 454 pyrosequencing. Surprisingly, GAOs were not the immediate causes of PAO failures, based on functional and population measurements. Pyrosequencing results suggested Dechloromonas and Tetrasphaera spp. may have also been PAOs, and additional potential GAOs were also identified. Full-scale systems typically have lower in-reactor acetate concentrations than laboratory SBRs, and so, previous laboratory studies may have overestimated the practical importance of GAOs as causes of EBPR failure.

  20. Accumulation of polychlorobiphenyl congeners and p,p'-DDE at environmental concentrations by corn and beans

    SciTech Connect

    Shane, L.A.; Bush, B.

    1989-02-01

    The uptake of polychlorinated biphenyl (PCB) congeners present at low concentrations in the environment was investigated in leaf composites of four crop species and final fruits at two sites. All four species preferentially accumulated the same eight congeners, although not in the same degree or rank. No bean species demonstrated a significant increase in accumulation over time, and corn significantly reduced its PCB load over time. Mechanisms are suggested for such behavior. Fruits were 100 times less contaminated than plant leaves.

  1. Lethal body concentrations and accumulation patterns determine time-dependent toxicity of cadmium in soil arthropods

    SciTech Connect

    Crommentuijn, T.; Doodeman, C.J.A.M.; Doornekamp, A.; Pol, J.J.C. van der; Bedaux, J.J.M.; Gestel, C.A.M. van )

    1994-11-01

    Time-dependent toxicity in bioassays is usually explained in terms of uptake and elimination kinetics of the toxicant. By comparing different species with essentially different accumulation kinetics, a firm test of this concept may be made. This article compares the sensitivity of six soil arthropods, the collembolans Orchesella cincta and Tomocerus minor, the oribatid mite Platynothrus peltifer, the isopods Porcellio scaber and Oniscus asellus, and the diplopod Cylindroiulus britannicus, when exposed to cadmium in the food. Survival was determined at various time intervals; accumulation of cadmium in the animals was measured at one time interval. Kinetic-based toxicity models were fitted to the data, and estimates were obtained for lethal body concentration, uptake rate constant, elimination rate constant, and ultimate LC50. Two different accumulation patterns could be discerned; these were correlated with time-survival relationships. One, species that have the possibility to eliminate cadmium will reach an equilibrium for the internal concentration and also an ultimate LC50. Two, species that are unable to eliminate cadmium but store it in the body will have an ultimate LC50 equal to zero. For these species the time in which the lethal body concentration is reached is more important. Taxonomically related species appeared to have comparable accumulation patterns, but lethal body concentrations differed. It is concluded that knowledge of the accumulation pattern is indispensable for the evaluation of species' sensitivities to toxicants.

  2. Effect of nitrogen and/or oxygen concentration on poly(3-hydroxybutyrate) accumulation by Halomonas boliviensis.

    PubMed

    García-Torreiro, María; Lu-Chau, Thelmo A; Lema, Juan M

    2016-09-01

    The behaviour of Halomonas boliviensis during growth in fed-batch culture under different kind of nutrient restrictions was examined. The metabolic switch between growth and accumulation phase is determined by the limitation in one or more essential nutrient for bacterial growth. The aim of this study was to test the effect of applying limitations of a essential nutrient, such as nitrogen, and the influence of different O2 concentrations on poly(3-hydroxybutyrate) (PHB) production during the accumulation phase. Single limitations of nitrogen and oxygen provoke PHB accumulations of 45 and 37 % (g g(-1)), respectively, while N limitation with low O2 supply causes the highest PHB accumulation of 73 %. The characterization of the PHB production with the strain H. boliviensis would allow a better optimization of the process and enrich the knowledge about the PHB production from strains different than Cupriavidus necator. PMID:27126501

  3. Higher blood concentrations of synthetic musks in women above fifty years than in younger women.

    PubMed

    Hutter, H-P; Wallner, P; Hartl, W; Uhl, M; Lorbeer, G; Gminski, R; Mersch-Sundermann, V; Kundi, M

    2010-03-01

    Synthetic musk compounds are widely used as fragrance ingredients in many consumer products. Little is known about their accumulation in humans and especially in older persons. In this study, we determined concentrations of 11 synthetic musks in women above fifty years and compared the results with earlier results from samples of young females. Blood was taken from 53 women above 50 years of age, visiting outpatients of the Department of Angiology at the Hanusch-Krankenhaus in Vienna, Austria. The used analytical methods consist of an extraction and clean-up step and a chromatographic analysis by GC/MS. Tonalide-D3 was used as recovery standard in all samples. Hexachlorobenzene (13)C(6) was used as internal standard. Study participants also completed a questionnaire on the use of cosmetics, about nutrition and other life-style aspects. The two substances which could be detected in higher percentages of the blood plasma samples were galaxolide (89 percent, maximum concentration 6900 ng/L) and musk xylene (62 percent, maximum concentration 190 ng/L). Regression analysis revealed a significant association of galaxolide concentration with frequent use of perfumes, deodorants and shampoos. Frequent use of soaps and fabric softener was associated with higher plasma concentrations of musk xylene. Nutrition habits, skin type, body mass index or surface area were not related to plasma concentration of these musk compounds. From the study group investigated older persons showed higher plasma concentrations. These findings could be due to the higher use of lotions and crèmes on face and hands and a more frequent use of skin care products because older persons reported more frequently dry skin. In addition, physiological aging related changes might be responsible for higher dermal absorption of synthetic musks. These results indicate that more focus on aging tissues is needed.

  4. Higher β-HCG concentrations and higher birthweights ensue from single vitrified embryo transfers.

    PubMed

    Keane, Kevin N; Mustafa, Kamarul Bahyah; Hinchliffe, Peter; Conceicao, Jason; Yovich, John L

    2016-08-01

    To examine the effect of cryopreservation on developmental potential of human embryos, this study compared quantitative β-HCG concentrations at pregnancy test after IVF-fresh embryo transfer (IVF-ET) with those arising after frozen embryo transfer (FET). It also tracked outcomes of singleton pregnancies resulting from single-embryo transfers that resulted in singleton live births (n = 869; with 417 derived from IVF-ET and 452 from FET). The initial serum β-HCG concentration indicating successful implantation was measured along with the birthweight of the ensuing infants. With testing at equivalent luteal phase lengths, the median pregnancy test β-HCG was significantly higher following FET compared with fresh IVF-ET (844.5 IU/l versus 369 IU/l; P < 0.001). Despite no significant difference in the average period of gestation (38 weeks 5 days for both groups), the mean birthweight of infants born following FET was significantly heavier by 161 g (3370 g versus 3209 g; P < 0.001). Furthermore, more infants exceeded 4000 g (P < 0.001) for FET although there was no significant difference for the macrosomic category (≥4500 g). We concluded that FET programme embryos lead to infants with equivalent (if not better) developmental potential compared with IVF-ET, demonstrated by higher pregnancy β-HCG concentrations and ensuing birthweights. PMID:27209497

  5. Impacts of CO2 concentration on growth, lipid accumulation, and carbon-concentrating-mechanism-related gene expression in oleaginous Chlorella.

    PubMed

    Fan, Jianhua; Xu, Hui; Luo, Yuanchan; Wan, Minxi; Huang, Jianke; Wang, Weiliang; Li, Yuanguang

    2015-03-01

    Biodiesel production by microalgae with photosynthetic CO2 biofixation is thought to be a feasible way in the field of bioenergy and carbon emission reduction. Knowledge of the carbon-concentrating mechanism plays an important role in improving microalgae carbon fixation efficiency. However, little information is available regarding the dramatic changes of cells suffered upon different environmental factors, such as CO2 concentration. The aim of this study was to investigate the growth, lipid accumulation, carbon fixation rate, and carbon metabolism gene expression under different CO2 concentrations in oleaginous Chlorella. It was found that Chlorella pyrenoidosa grew well under CO2 concentrations ranging from 1 to 20 %. The highest biomass and lipid productivity were 4.3 g/L and 107 mg/L/day under 5 % CO2 condition. Switch from high (5 %) to low (0.03 %, air) CO2 concentration showed significant inhibitory effect on growth and CO2 fixation rate. The amount of the saturated fatty acids was increased obviously along with the transition. Low CO2 concentration (0.03 %) was suitable for the accumulation of saturated fatty acids. Reducing the CO2 concentration could significantly decrease the polyunsaturated degree in fatty acids. Moreover, the carbon-concentrating mechanism-related gene expression revealed that most of them, especially CAH2, LCIB, and HLA3, had remarkable change after 1, 4, and 24 h of the transition, which suggests that Chlorella has similar carbon-concentrating mechanism with Chlamydomonas reinhardtii. The findings of the present study revealed that C. pyrenoidosa is an ideal candidate for mitigating CO2 and biodiesel production and is appropriate as a model for mechanism research of carbon sequestration.

  6. Damage accumulation in ion-irradiated Ni-based concentrated solid-solution alloys

    DOE PAGES

    Ullah, Mohammad W.; Aidhy, Dilpuneet S.; Zhang, Yanwen; Weber, William J.

    2016-01-01

    We investigate Irradiation-induced damage accumulation in Ni0.8Fe0.2 and Ni0.8Cr0.2 alloys by using molecular dynamics simulations to assess possible enhanced radiation-resistance in these face-centered cubic (fcc), single-phase, concentrated solid-solution alloys, as compared with pure fcc Ni.

  7. Transient concentrations of NaCl affect the PHA accumulation in mixed microbial culture.

    PubMed

    Palmeiro-Sánchez, T; Fra-Vázquez, A; Rey-Martínez, N; Campos, J L; Mosquera-Corral, A

    2016-04-01

    The present study explores the feasibility of the accumulation of polyhydroxyalkanoates (PHAs) under the presence of transient concentrations of added sodium chloride, by means of a mixed microbial culture (MMC). This culture was enriched on a mixture of volatile fatty acids (VFAs) containing 0.8g Na(+)/L as NaOH. This MMC presented a maximum PHA accumulation capacity of 53wt% with 27Cmol% HV. Accumulation experiments performed with added NaCl at concentrations of 7, 13 and 20g/L shown that this salt provoked a decrease of the biomass PHA production rate, with an IC50 value close to 7gNaCl/L. The accumulated PHA was lower than the corresponding value of the assay without the addition of salt. Furthermore, the composition of the biopolymer, in terms of HB:HV ratio, changed from 2.71 to 6.37Cmol/Cmol, which means a HV decrease between 27 and 14Cmol%. Summarizing, the PHA accumulation by a MMC non-adapted to saline conditions affected the polymer composition and lead to lower production yields and rates than in absence of added NaCl. PMID:26780589

  8. Metal accumulation and metallothionein concentrations in tree swallow nestlings near acidified lakes

    SciTech Connect

    St. Louis, V.; Breebaart, L. . Dept. of Zoology); Barlow, J.C. . Dept. of Zoology Royal Ontario Museum, Toronto, Ontario . Dept. of Ornithology); Klaverkamp, J.F. . Dept. of Fisheries and Oceans)

    1993-07-01

    The authors studied metal accumulation in hepatic and renal tissues of tree swallow (Tachycineta bicolor) nestlings at acidified and nonacid reference lakes in northwestern Ontario. Hepatic concentrations of metallothionein (metal-binding proteins, MT) in tree swallow nestlings were negatively correlated with pH of the nest-site lake. Combined concentrations of Cu and Zn in the liver were correlated with liver MT concentrations, but Cd was not. Although no overt signs of metal toxicity were observed in nestlings near acid lakes, the results clearly provided evidence that metals are transferred from acid lakes to birds and that these metals are correlated with increases in hepatic MT production.

  9. Higher milk fat content is associated with higher 25-hydroxyvitamin D concentration in early childhood.

    PubMed

    Vanderhout, Shelley M; Birken, Catherine S; Parkin, Patricia C; Lebovic, Gerald; Chen, Yang; O'Connor, Deborah L; Maguire, Jonathon L

    2016-05-01

    Current guidelines for cow's milk consumption in children older than age 2 years suggest 1% or 2% milk to reduce the risk of obesity. Given that milk is the main dietary source of vitamin D for North American children and that vitamin D is fat soluble, we hypothesized 25-hydroxyvitamin D (25(OH)D) concentration to be positively associated with the fat content of milk. The objective was to determine the relationship between the fat content of milk consumed and the serum 25(OH)D concentration; our secondary objective was to explore the role that the volume of milk consumed played in this relationship. We completed a cross-sectional study of children aged 12-72 months in the TARGetKids! research network. Multivariable linear regression was used to test the association between milk fat content and child 25(OH)D, adjusted for clinically relevant covariates. The interaction between volume of milk and fat content was examined. Two thousand eight hundred fifty-seven children were included in the analysis. The fat content of milk was positively associated with 25(OH)D (p = 0.03), and the interaction between the volume of milk consumed and the milk fat content was statistically significant (p = 0.005). Children who drank 1% milk needed 2.46 cups (95% confidence interval (CI) 2.38-2.54) of milk to have a 25(OH)D concentration similar to that of children who drank 1 cup of homogenized milk (3.25% fat). Children who consumed 1% milk had 2.05 (95% CI 1.73-2.42) times higher odds of having a 25(OH)D concentration <50 nmol/L compared with children who consumed homogenized milk. In conclusion, recommendations for children to drink lower-fat milk (1% or 2%) may compromise serum 25(OH)D levels and may require study to ensure optimal childhood health.

  10. Peatlands as Dynamic Biogeochemical Ecotones: Elemental Concentrations, Stoichiometries and Accumulation in Peatland Soils of Ontario, Canada

    NASA Astrophysics Data System (ADS)

    Moore, T. R.; Wang, M.; Talbot, J.; Riley, J. L.

    2015-12-01

    Peatlands act as biogeochemical interfaces between terrestrial and aquatic systems and are 'hotspots', particularly for carbon cycling and the accumulation of nutrients and other elements within the peat profile. This results in storage of substantial amounts of carbon, nutrients and metals, particularly in northern peatlands. Using a data base of over 400 peat profiles and 1700 individual peat samples from bog, fen and swamp sites in Ontario, Canada, we examine the profile concentrations of C, N, P, Ca, Mg, K, Hg, Pb, As, Cu, Mn, Zn, Fe and Al, and estimate the storage and accumulation of these elements. We show how these profiles, spatial patterns, stoichiometries and accumulation rates are controlled by biogeochemical processes and influenced by geochemical setting, hydrology, atmospheric input and pollution, and ecological and microbial transformations.

  11. Selenium accumulation and selenium tolerance of salt grass from soils with elevated concentrations of Se and salinity.

    PubMed

    Wu, L; Huang, Z Z

    1991-12-01

    Biomass production, selenium accumulation, and the role of the bioextraction of selenium by salt grass (Distichlis spicata L.) in soils with elevated concentrations of Se and salinity at Kesterson, California, were studied. Salt grass contributed more than 80% vegetative coverage and 90% dry weight in the grassland communities where the soil Se concentrations were 100 times (1000 to 3000 micrograms kg-1) higher than the Se concentrations found in soils of the control sites. No evidence for evolution of Se tolerance was found in the salt grass populations. The successful colonization of salt grass in the soil with elevated Se and salinity is attributable to the presence of high concentrations of soil sulfate. Salt grass accumulated less Se than other salt-tolerant plant species existing in the same area, and no predation of animals and insects on salt grass has been noticed. Salt grass can transpire substantial amounts of volatile Se through its plant tissue. Under field conditions, a 1-m2 salt grass plot may produce 180 micrograms volatile selenium per day. However, no reduction of soil Se concentration in the salt grass habitat was detected over a period of 1 year. A long-term monitoring of Se status is needed in order to make predictions of the effectiveness of efforts to clean up Se-contaminated soils through the use of native plant species.

  12. Boron uptake and accumulation by higher plants: A literature review: Final report

    SciTech Connect

    Sposito, G.; Calderone, S.J.

    1988-05-01

    This study provides a review of the literature on boron uptake and accumulation by higher plants, particularly trees. It addresses those aspects of the soil chemistry of boron that are most relevant to uptake by trees, then discusses the plant biochemistry of boron, its uptake and accumulation in plant tissue, and its phytotoxicity symptoms in plant species. The literature reviewed suggests that boron uptake is accomplished by a passive, massflow mechanism, as opposed to a metabolic process, with the most likely chemical form taken up being the neutral complex, H/sub 3/BO/sub 3/. The biochemical role of boron is not well understood, but evidence exists for its involvement with carbohydrate transformations and the control of growth-regulating compounds. Because of the mass-flow uptake mechanism, the distribution of boron in trees is connected intimately with the patterns of transpiration, which are species-dependent. Precise data on the effect of plant genotype on boron uptake, however, were not found in the published literature. The phytotoxicity symptoms of boron in trees also are species-dependent, although a consensus does exist as to the general nature of external symptoms and the basis of boron tolerance.

  13. Damage accumulation in ion-irradiated Ni-based concentrated solid-solution alloys

    SciTech Connect

    Ullah, Mohammad W.; Aidhy, Dilpuneet S.; Zhang, Yanwen; Weber, William J.

    2016-01-01

    We investigate Irradiation-induced damage accumulation in Ni0.8Fe0.2 and Ni0.8Cr0.2 alloys by using molecular dynamics simulations to assess possible enhanced radiation-resistance in these face-centered cubic (fcc), single-phase, concentrated solid-solution alloys, as compared with pure fcc Ni.

  14. Will an algal CO2-concentrating mechanism work in higher plants?

    PubMed

    Meyer, Moritz T; McCormick, Alistair J; Griffiths, Howard

    2016-06-01

    Many algae use a biophysical carbon concentrating mechanism for active accumulation and retention of inorganic carbon within chloroplasts, with CO2 fixation by RuBisCO within a micro-compartment, the pyrenoid. Engineering such mechanisms into higher plant chloroplasts is a possible route to augment RuBisCO operating efficiency and photosynthetic rates. Significant progress has been made recently in characterising key algal transporters and identifying factors responsible for the aggregation of RuBisCO into the pyrenoid. Several transporters have now also been successfully incorporated into higher plant chloroplasts. Consistent with the predictions from modelling, regulation of higher plant plastidic carbonic anhydrases and some form of RuBisCO aggregation will be needed before the mechanism delivers potential benefits. Key research priorities include a better understanding of the regulation of the algal carbon concentrating mechanism, advancing the fundamental characterisation of known components, evaluating whether higher plant chloroplasts can accommodate a pyrenoid, and, ultimately, testing transgenic lines under realistic growth conditions. PMID:27194106

  15. Hydrophilic nanoparticles stabilising mesophase curvature at low concentration but disrupting mesophase order at higher concentrations.

    PubMed

    Beddoes, Charlotte M; Berge, Johanna; Bartenstein, Julia E; Lange, Kathrin; Smith, Andrew J; Heenan, Richard K; Briscoe, Wuge H

    2016-07-13

    Using high pressure small angle X-ray scattering (HP-SAXS), we have studied monoolein (MO) mesophases at 18 wt% hydration in the presence of 10 nm silica nanoparticles (NPs) at NP-lipid number ratios (ν) of 1 × 10(-6), 1 × 10(-5) and 1 × 10(-4) over the pressure range 1-2700 bar and temperature range 20-60 °C. In the absence of the silica NPs, the pressure-temperature (p-T) phase diagram of monoolein exhibited inverse bicontinuous cubic gyroid (Q), lamellar alpha (Lα), and lamellar crystalline (Lc) phases. The addition of the NPs significantly altered the p-T phase diagram, changing the pressure (p) and the temperature (T) at which the transitions between these mesophases occurred. In particular, a strong NP concentration effect on the mesophase behaviour was observed. At low NP concentration, the p-T region pervaded by the Q phase and the Lα-Q mixture increased, and we attribute this behaviour to the NPs forming clusters at the mesophase domain boundaries, encouraging transition to the mesophase with a higher curvature. At high NP concentrations, the Q phase was no longer observed in the p-T phase diagram. Instead, it was dominated by the lamellar (L) phases until the transition to a fluid isotropic (FI) phase at 60 °C at low pressure. We speculate that NPs formed aggregates with a "chain of pearls" structure at the mesophase domain boundaries, hindering transitions to the mesophases with higher curvatures. These observations were supported by small angle neutron scattering (SANS) and scanning electron microscopy (SEM). Our results have implications to nanocomposite materials and nanoparticle cellular entry where the interactions between NPs and organised lipid structures are an important consideration. PMID:27340807

  16. The effect of low fluoride concentrations on microdamage accumulation in mouse tibias under impact loading

    NASA Astrophysics Data System (ADS)

    Luo, Qing; Chen, Nan; Zhou, Yan-Heng; Rong, Qi-Guo

    2015-12-01

    Microdamage accumulation in bone is one of the mechanisms for energy dissipation during the fracture process. Changes in the ultrastructure and composition of bone constituents due to aging or diseases could affect microdamage accumulation. Low concentration (1 mM) of sodium fluoride (NaF) has been used in this study to investigate the effect of ultrastructural changes on microdamage accumulation in mouse tibias following free-fall impact loadings. Twenty-two tibias were divided randomly into control and NaF-treated groups. Free-fall impact loading was conducted twice on each tibia to produce microdamage. The elastic modulus of NaF-treated tibias decreased significantly after the impact loadings, while there was no significant difference in the modulus of untreated samples between pre- and post-damage loadings. Microdamage morphology analysis showed that less and shorter microcracks existed in NaF-treated tibias compared with control bones. Meanwhile, more and longer microcracks were observed in tensile regions in untreated samples compared with that in compressive regions, whereas no significant difference was observed between tensile and compressive regions in NaF-treated bones. The results of this study indicate that more energy is required to generate microcracks in NaF-treated bone than in normal bone. A low concentration of fluoride treatment may increase the toughness of bone under impact loading.

  17. Pressure drop increase by biofilm accumulation in spiral wound RO and NF membrane systems: role of substrate concentration, flow velocity, substrate load and flow direction.

    PubMed

    Vrouwenvelder, J S; Hinrichs, C; Van der Meer, W G J; Van Loosdrecht, M C M; Kruithof, J C

    2009-01-01

    In an earlier study, it was shown that biofouling predominantly is a feed spacer channel problem. In this article, pressure drop development and biofilm accumulation in membrane fouling simulators have been studied without permeate production as a function of the process parameters substrate concentration, linear flow velocity, substrate load and flow direction. At the applied substrate concentration range, 100-400 microg l(-1) as acetate carbon, a higher concentration caused a faster and greater pressure drop increase and a greater accumulation of biomass. Within the range of linear flow velocities as applied in practice, a higher linear flow velocity resulted in a higher initial pressure drop in addition to a more rapid and greater pressure drop increase and biomass accumulation. Reduction of the linear flow velocity resulted in an instantaneous reduction of the pressure drop caused by the accumulated biomass, without changing the biofilm concentration. A higher substrate load (product of substrate concentration and flow velocity) was related to biomass accumulation. The effect of the same amount of accumulated biomass on the pressure drop increase was related to the linear flow velocity. A decrease of substrate load caused a gradual decline in time of both biomass concentration and pressure drop increase. It was concluded that the pressure drop increase over spiral wound reverse osmosis (RO) and nanofiltration (NF) membrane systems can be reduced by lowering both substrate load and linear flow velocity. There is a need for RO and NF systems with a low pressure drop increase irrespective of the biomass formation. Current efforts to control biofouling of spiral wound membranes focus in addition to pretreatment on membrane improvement. According to these authors, adaptation of the hydrodynamics, spacers and pressure vessel configuration offer promising alternatives. Additional approaches may be replacing heavily biofouled elements and flow direction reversal.

  18. Species richness and selenium accumulation of plants in soils with elevated concentration of selenium and salinity.

    PubMed

    Huang, Z Z; Wu, L

    1991-12-01

    Field studies were conducted in soils with elevated concentrations of Se and salinity at Kesterson, California. Biomass distribution, species richness, and selenium accumulation of plants were examined for two sites where 15 cm of surface soil was removed and replaced with fill dirt in the fall of 1989, and two sites were native soil cover. The Se concentrations in the top 15 cm of fill dirt ranged from undetectable to 36 ng g-1. For the native soil sites, Se levels ranged from 75 to 550 ng g-1. Soil Se concentrations below 15 cm ranged from 300 to 700 ng g-1 and were comparable between the fill dirt and the native soil sites. At least 20 different plant species were brought into the two fill dirt sites with the top soil. Avena fatua L., Bassia hyssopifolia Kuntze Rev. Gen. Pl., Centaurea solstitialis L., Erysimum officianale L., Franseria acanthicarpa Cav. Icon., and Melilotus indica (L.) All. contributed over 60% of the total biomass. Only 5 species were found in the native soil sites, and salt grass (Distichlis spicata L.) was the predominant species and accounted for over 80% of the total biomass. Between 1989 and 1990, two years after the surface soil replacement, the two fill dirt sites had a 70% reduction in species richness. Plant tissue selenium concentrations were found to be quite variable between plant species and between sites of sampling. At the fill dirt sites, the plant species with deep root systems accumulated greater amounts of selenium than the shallow-rooted species. The soil selenium concentration of the field soil had no negative effect on pollen fertility, seed set, and seed germination for the plant species examined. However, seedling growth was impaired by the soil selenium concentrations. This suggests that a selection pressure of soil Se concentration may have been imposed on plant species such as M. indica in an early stage of its life cycle.

  19. Growth, carbon dioxide exchange and mineral accumulation in potatoes grown at different magnesium concentrations

    NASA Technical Reports Server (NTRS)

    Cao, W.; Tibbitts, T. W.

    1992-01-01

    Plants of Norland potatoes (Solanum tuberosum L.) were maintained for 42 days at Mg concentrations of 0.05, 0.125, 0.25, 1, 2, and 4 mM in a nonrecirculating nutrient film system under controlled environment. With the increased Mg supply from 0.05 to 4 mM, Mg concentrations in the leaves of the 42-day old plants increased significantly from 1.1 to 11.2 mg g-1 dry weight. Plant leaf area and plant and tuber dry weights increased with increased Mg concentrations up to 1 mM in solution or 6.7 mg g-1 in leaves, and then decreased with further increases in Mg concentrations. Rates of CO2 assimilation measured on leaflets in situ at ambient and various intercellular CO2 concentrations were consistently lower at 0.05 and 4 mM Mg than at other Mg treatments, which may indicate decreased photosynthetic activity in mesophyll tissues at the lowest and highest Mg concentrations. Dark respiration rates in leaves were highest at 0.05 and 4 mM Mg, lowest at 0.25 and 1 mM Mg, and intermediate at 0.125 and 2 mM Mg. The different Mg treatments also influenced accumulation of other minerals in leaves. Leaf concentrations of Ca and Mn decreased with increased Mg supply except that Ca and Mn were lower at 0.05 mM than at 0.125 mM Mg. Leaf K concentrations were lower at 1, 2 and 4 mM Mg than at other Mg treatments. Foliar concentrations of P, Fe, Zn, and Cu had small but inconsistent variation with different Mg concentrations. Leaf concentrations of N, S, and B were similar at different Mg concentrations. This study demonstrates that various Mg nutrition, along with altered accumulation of other nutrients, could regulate dry matter production in potatoes by affecting not only leaf area but also leaf carbon dioxide assimilation and respiration.

  20. Different palm oil preparations reduce plasma cholesterol concentrations and aortic cholesterol accumulation compared to coconut oil in hypercholesterolemic hamsters.

    PubMed

    Wilson, Thomas A; Nicolosi, Robert J; Kotyla, Timothy; Sundram, Kalyana; Kritchevsky, David

    2005-10-01

    Several studies have reported on the effect of refined, bleached and deodorized palm oil (RBD-PO) incorporation into the diet on blood cholesterol concentrations and on the development of atherosclerosis. However, very little work has been reported on the influence of red palm oil (RPO), which is higher in carotenoid and tocopherol content than RBD-PO. Thus, we studied the influence of RPO, RBD-PO and a RBD-PO plus red palm oil extract (reconstituted RBD-PO) on plasma cholesterol concentrations and aortic accumulation vs. hamsters fed coconut oil. Forty-eight F1B Golden Syrian hamsters (Mesocricetus auratus) (BioBreeders, Watertown, MA) were group housed (three/cage) in hanging polystyrene cages with bedding in an air-conditioned facility maintained on a 12-h light/dark cycle. The hamsters were fed a chow-based hypercholesterolemic diet (HCD) containing 10% coconut oil and 0.1% cholesterol for 2 weeks at which time they were bled after an overnight fast and segregated into four groups of 12 with similar plasma cholesterol concentrations. Group 1 continued on the HCD, Group 2 was fed the HCD containing 10% RPO in place of coconut oil, Group 3 was fed the HCD containing 10% RBD-PO in place of coconut oil and Group 4 was fed the HCD with 10% reconstituted RBD-PO for an additional 10 weeks. Plasma total cholesterol (TC) and non-high-density lipoprotein-cholesterol (HDL-C) (very low- and low-density lipoprotein) concentrations were significantly lower in the hamsters fed the RPO (-42% and -48%), RBD-PO (-32% and -36%) and the reconstituted RBD-PO (-37% and -41%) compared to the coconut oil-fed hamsters. Plasma HDL-C concentrations were significantly higher by 14% and 31% in hamsters fed the RBD-PO and RPO compared to the coconut oil-fed hamsters. Plasma triglyceride (TG) concentrations were significantly lower in hamsters fed RBD-PO (-32%) and the reconstituted RBD-PO (-31%) compared to the coconut oil-fed hamsters. The plasma gamma-tocopherol concentrations were higher

  1. Different palm oil preparations reduce plasma cholesterol concentrations and aortic cholesterol accumulation compared to coconut oil in hypercholesterolemic hamsters.

    PubMed

    Wilson, Thomas A; Nicolosi, Robert J; Kotyla, Timothy; Sundram, Kalyana; Kritchevsky, David

    2005-10-01

    Several studies have reported on the effect of refined, bleached and deodorized palm oil (RBD-PO) incorporation into the diet on blood cholesterol concentrations and on the development of atherosclerosis. However, very little work has been reported on the influence of red palm oil (RPO), which is higher in carotenoid and tocopherol content than RBD-PO. Thus, we studied the influence of RPO, RBD-PO and a RBD-PO plus red palm oil extract (reconstituted RBD-PO) on plasma cholesterol concentrations and aortic accumulation vs. hamsters fed coconut oil. Forty-eight F1B Golden Syrian hamsters (Mesocricetus auratus) (BioBreeders, Watertown, MA) were group housed (three/cage) in hanging polystyrene cages with bedding in an air-conditioned facility maintained on a 12-h light/dark cycle. The hamsters were fed a chow-based hypercholesterolemic diet (HCD) containing 10% coconut oil and 0.1% cholesterol for 2 weeks at which time they were bled after an overnight fast and segregated into four groups of 12 with similar plasma cholesterol concentrations. Group 1 continued on the HCD, Group 2 was fed the HCD containing 10% RPO in place of coconut oil, Group 3 was fed the HCD containing 10% RBD-PO in place of coconut oil and Group 4 was fed the HCD with 10% reconstituted RBD-PO for an additional 10 weeks. Plasma total cholesterol (TC) and non-high-density lipoprotein-cholesterol (HDL-C) (very low- and low-density lipoprotein) concentrations were significantly lower in the hamsters fed the RPO (-42% and -48%), RBD-PO (-32% and -36%) and the reconstituted RBD-PO (-37% and -41%) compared to the coconut oil-fed hamsters. Plasma HDL-C concentrations were significantly higher by 14% and 31% in hamsters fed the RBD-PO and RPO compared to the coconut oil-fed hamsters. Plasma triglyceride (TG) concentrations were significantly lower in hamsters fed RBD-PO (-32%) and the reconstituted RBD-PO (-31%) compared to the coconut oil-fed hamsters. The plasma gamma-tocopherol concentrations were higher

  2. Higher lipid accumulation in broilers fed on saturated fats than in those fed on unsaturated fats.

    PubMed

    Sanz, M; Flores, A; De Ayala, P P; Lopez-Bote, C J

    1999-03-01

    1. Two experiments were conducted to assess the effect of fat sources differing in degree of saturation on the performance of and fat deposition in broiler chickens fed on isocaloric and isonitrogenous diets. 2. There were no differences in initial body weight between sexes but female broilers had lower daily gains (P<0.0001), final weights (P<0.0001) and food intakes (P<0.0001) than males. Abdominal fat pad weight was lower in male broilers than in female (P<0.001). 3. There were no significant differences in intake, weight gain, final body weight or food-to-gain ratios between birds fed on diets differing solely in the degree of fat saturation. Broilers fed on diets containing an animal fat blend or tallow had higher abdominal fat pad weight (P<0.001) and intramuscular lipid content (P=0.0085) than those fed on diets containing sunflower oil. 4. It was concluded that dietary fat saturation affects fat accumulation in broiler chickens.

  3. Novel Approaches for the Accumulation of Oxygenated Intermediates to Multi-Millimolar Concentrations

    PubMed Central

    Krebs, Carsten; Dassama, Laura M. K.; Matthews, Megan L.; Jiang, Wei; Price, John C.; Korboukh, Victoria; Li, Ning; Bollinger, J. Martin

    2012-01-01

    Metalloenzymes that utilize molecular oxygen as a co-substrate catalyze a wide variety of chemically difficult oxidation reactions. Significant insight into the reaction mechanisms of these enzymes can be obtained by the application of a combination of rapid kinetic and spectroscopic methods to the direct structural characterization of intermediate states. A key limitation of this approach is the low aqueous solubility (< 2 mM) of the co-substrate, O2, which undergoes further dilution (typically by one-third or one-half) upon initiation of reactions by rapid-mixing. This situation imposes a practical upper limit on [O2] (and therefore on the concentration of reactive intermediate(s) that can be rapidly accumulated) of ∼1-1.3 mM in such experiments as they are routinely carried out. However, many spectroscopic methods benefit from or require significantly greater concentrations of the species to be studied. To overcome this problem, we have recently developed two new approaches for the preparation of samples of oxygenated intermediates: (1) direct oxygenation of reduced metalloenzymes using gaseous O2 and (2) the in situ generation of O2 from chlorite catalyzed by the enzyme chlorite dismutase (Cld). Whereas the former method is applicable only to intermediates with half lives of several minutes, owing to the sluggishness of transport of O2 across the gas-liquid interface, the latter approach has been successfully applied to trap several intermediates at high concentration and purity by the freeze-quench method. The in situ approach permits generation of a pulse of at least 5 mM O2 within ∼ 1 ms and accumulation of O2 to effective concentrations of up to ∼ 11 mM (i.e. ∼ 10-fold greater than by the conventional approach). The use of these new techniques for studies of oxygenases and oxidases is discussed. PMID:24368870

  4. Reverse osmosis concentrate treatment via a PAC-MF accumulative countercurrent adsorption process.

    PubMed

    Zhao, Chunxia; Gu, Ping; Cui, Hangyu; Zhang, Guanghui

    2012-01-01

    Organic pollutants in reverse osmosis (RO) concentrates from wastewater reclamation are mainly comprised of low molecular weight biorefractory compounds. Generally, advanced oxidation methods for oxidizing these organics require a relatively high level of energy consumption. In addition, conventional adsorption removal methods require a large dose of activated carbon. However, the dose can be reduced if its full adsorption capacity can be used. Therefore, the combined technology of powdered activated carbon (PAC) adsorption and microfiltration (MF) membrane filtration was studied to develop a countercurrent two-stage adsorption process. A PAC accumulative adsorption prediction method was proposed based on the verification of a PAC multi-stage adsorption capacity equation. Moreover, the prediction method was amended for a more accurate prediction of the effluent quality because adsorption isotherm constants were affected by the initial adsorbate concentration. The required PAC dose for the accumulative countercurrent two-stage adsorption system was 0.6 g/L, whereas that of the conventional adsorption process was 1.05 g/L when the dilution factor(F) was 0.1 and the COD and DOC removal rates were set to 70% and 68.1%, respectively. Organic pollutants were satisfactorily removed with less consumption of PAC. Effluent from this combined technology can be further reclaimed by an RO process to improve the overall recovery rate to between 91.0% and 93.8% with both economic and environmental benefits. PMID:22082527

  5. Reverse osmosis concentrate treatment via a PAC-MF accumulative countercurrent adsorption process.

    PubMed

    Zhao, Chunxia; Gu, Ping; Cui, Hangyu; Zhang, Guanghui

    2012-01-01

    Organic pollutants in reverse osmosis (RO) concentrates from wastewater reclamation are mainly comprised of low molecular weight biorefractory compounds. Generally, advanced oxidation methods for oxidizing these organics require a relatively high level of energy consumption. In addition, conventional adsorption removal methods require a large dose of activated carbon. However, the dose can be reduced if its full adsorption capacity can be used. Therefore, the combined technology of powdered activated carbon (PAC) adsorption and microfiltration (MF) membrane filtration was studied to develop a countercurrent two-stage adsorption process. A PAC accumulative adsorption prediction method was proposed based on the verification of a PAC multi-stage adsorption capacity equation. Moreover, the prediction method was amended for a more accurate prediction of the effluent quality because adsorption isotherm constants were affected by the initial adsorbate concentration. The required PAC dose for the accumulative countercurrent two-stage adsorption system was 0.6 g/L, whereas that of the conventional adsorption process was 1.05 g/L when the dilution factor(F) was 0.1 and the COD and DOC removal rates were set to 70% and 68.1%, respectively. Organic pollutants were satisfactorily removed with less consumption of PAC. Effluent from this combined technology can be further reclaimed by an RO process to improve the overall recovery rate to between 91.0% and 93.8% with both economic and environmental benefits.

  6. Anaerobic biodegradability and digestion in accumulation systems for concentrated black water and kitchen organic-wastes.

    PubMed

    Elmitwalli, T A; van Leeuwen, M; Kujawa-Roeleveld, K; Sanders, W; Zeeman, G

    2006-01-01

    The feasibility of two accumulation-systems (AC) for anaerobic digestion and storage of concentrated black water with (AC1) or without (AC2) urine + kitchen organic-wastes was investigated. The waste(water) was collected by two vacuum toilet/transport systems. The influent-total COD of the AC2 (53,000 mg/L) was more concentrated by four times than that of the AC1. The suspended COD represented the major part (71-73%) of influent total COD of the two systems. The batch-experiments results showed a high anaerobic biodegradability of the waste(water) (> 85%). The AC systems demonstrated stable performance. There was no inhibition effect of NH4 and VFA concentration decreased in time. Total COD removal of 58% was achieved in both systems, after 105 days at 20 degrees C. Moreover, if only the supernatant in AC1 is withdrawn and the settled sludge stays for the next runs, only 20% of the influent total COD will be in the supernatant. In AC2, 74% of influent ortho-P was removed by precipitation. Therefore, the settled sludge in the AC2 had a high total-P concentration of 1,300 mg/L. The C:N:P ratios of the supernatant and the sludge were 26:13:1 and 35:4.5:1, respectively, in the AC1, and were 28:14:1 and 32:2.4:1, respectively, in AC2.

  7. Nitrite accumulation performance of aerobic MBBR treating Lurgi coal gasification waste water by adjusting pollutant load and DO concentration.

    PubMed

    Li, Hui-Qiang; Han, Hong-Jun

    2015-01-01

    An aerobic moving bed biofilm reactor (MBBR) was adopted to treat Lurgi coal gasification waste water (LCGW) in about 10 months. The pollutant load and dissolve oxygen (DO) concentration were adjusted by trying to maximize the accumulation of [Formula: see text] in the MBBR for LCGW treatment. The highest [Formula: see text] accumulation proportion [Formula: see text] was 73.9%, but was not stable with influent chemical oxygen demand (COD) and DO concentrations of around 1000 and 1.5 mg/L, respectively. Around 1500 mg/L of influent COD concentration and 1.5 mg/L of DO concentration were proper operation conditions for the aerobic MBBR to achieve relatively stable [Formula: see text] accumulation, with [Formula: see text] ratio at 53% and [Formula: see text] ratio at just 4.3% in the effluent. More specifically, free ammonia concentration and DO concentration affected [Formula: see text] accumulation much more obvious than phenols concentration. The activity and quantity of nitrifying bacteria growth in suspended sludge and biofilm of the MBBR were monitored simultaneously to explain the variations of [Formula: see text] accumulation performance under different operation conditions. An aerobic moving bed biofilm reactor (MBBR) was adopted to treat Lurgi coal gasification waste water (LCGW)in about 10 months. The pollutant load and dissolve oxygen (DO) concentration were adjusted by trying to maximize the accumulation of NO(−)(2)−N in the MBBR for LCGW treatment. The highest NO(−)(2)−N accumulation proportion(NO(−)(2)−Neffluent/TN effluent) was 73.9%, but was not stable with influent chemical oxygen demand (COD) and DO concentrations of around 1000 and 1.5 mg/L, respectively. Around 1500 mg/L of influent COD concentration and 1.5 mg/L of DO concentration were proper operation conditions for the aerobic MBBR to achieve relatively stable NO(−)(2)−N accumulation,with NO(−)(2)−N/TN ratio at 53% and NO(-)(3)−N/TN ratio at just 4.3% in the

  8. Capacity of the aquatic fern (Salvinia minima Baker) to accumulate high concentrations of nickel in its tissues, and its effect on plant physiological processes.

    PubMed

    Fuentes, Ignacio I; Espadas-Gil, Francisco; Talavera-May, Carlos; Fuentes, Gabriela; Santamaría, Jorge M

    2014-10-01

    An experiment was designed to assess the capacity of Salvinia minima Baker to uptake and accumulate nickel in its tissues and to evaluate whether or not this uptake can affect its physiology. Our results suggest that S. minima plants are able to take up high amounts of nickel in its tissues, particularly in roots. In fact, our results support the idea that S. minima might be considered a hyper-accumulator of nickel, as it is able to accumulate 16.3 mg g(-1) (whole plant DW basis). Our results also showed a two-steps uptake pattern of nickel, with a fast uptake of nickel at the first 6 to 12h of being expose to the metal, followed by a slow take up phase until the end of the experiment at 144 h. S. minima thus, may be considered as a fern useful in the phytoremediation of residual water bodies contaminated with this metal. Also from our results, S. minima can tolerate fair concentrations of the metal; however, at concentrations higher than 80 μM Ni (1.5 mg g(-1) internal nickel concentration), its physiological performance can be affected. For instance, the integrity of cell membranes was affected as the metal concentration and exposure time increased. The accumulation of high concentrations of internal nickel did also affect photosynthesis, the efficiency of PSII, and the concentration of photosynthetic pigments, although at a lower extent.

  9. Impact of lignite and hydrocarbon accumulations on {sup 222}Radon concentrations in drinking water supplies

    SciTech Connect

    Wolosz, T.H.

    1995-09-01

    Lignite and hydrocarbon accumulations are efficient uranium sinks, and {sup 222}Radon has been associated with the presence of hydrocarbon-trapping faults and salt domes. Lung exposure to this radioactive respiratory carcinogen can result upon the release of radon from domestic water during normal household activities. To determine if an association was present between elevated radon levels and factors affecting the distribution of {sup 238}Uranium and its decay products, 27 individual water wells and 48 public water systems of nine rural counties in and adjacent to an Texas Eocene Wilcox lignite belt were sampled and the water assayed. Radon levels in these water supplies ranged from <10 to 1359 pCi 1{sup -1}. Statistical analysis of radon concentrations and variables representing the presence of potential sinks was performed. A highly significant model (P,0.001) that explained 21.3% of radon variation. Mapping showed the highest radon concentrations were from lignite belt samples, which suggests that lignite may be a radionuclide source. The proposed standard for radon in public drinking water supplies is 300 pCi1{sup -1}. Thus, the demonstrated association between elevated radon concentrations and petroleum fields and low-rank coal may provide an informational tool for decision-making with regard to drilling public and private domestic water wells in the Eastern United States.

  10. Concentration and distribution of cobalt in higher plants: The use of micro-PIXE spectroscopy

    NASA Astrophysics Data System (ADS)

    Bakkaus, E.; Gouget, B.; Gallien, J.-P.; Khodja, H.; Carrot, F.; Morel, J. L.; Collins, R.

    2005-04-01

    Cobalt is not classified as an essential element for plants, however, it is usually described as "beneficial". This trace element can be a contaminant in soils due to agricultural additives or metal refineries. Certain plants species have the ability to extract metals (such as Co) from soils, thus, cleaning the environment. Therefore, knowledge of the physiological mechanisms of metal absorption is required to improve these phytoremediation technologies. Patterns of cobalt accumulation and storage were determined in tomato (Lycopersicon esculentum) and wheat (Triticum aestivum) species. Plants were grown in nutrient solutions, with different Co treatments, using controlled environmental conditions. The spatial distributions of K, Ca, Fe and Co in whole plants, and in leaf and stem sections, were examined by micro-PIXE. In conjunction, total Co concentrations were determined by ICP-MS. Micro-PIXE spectroscopy proved to be a convenient technique for indicating Co concentrations and distribution patterns in these plants. This knowledge aids in the identification of vegetal Co sequestration and, thus, helps to unravel how Co is transported in higher plants.

  11. Soybean Ferritin Expression in Saccharomyces cerevisiae Modulates Iron Accumulation and Resistance to Elevated Iron Concentrations

    PubMed Central

    de Llanos, Rosa; Martínez-Garay, Carlos Andrés; Fita-Torró, Josep; Romero, Antonia María; Martínez-Pastor, María Teresa

    2016-01-01

    ABSTRACT Fungi, including the yeast Saccharomyces cerevisiae, lack ferritin and use vacuoles as iron storage organelles. This work explored how plant ferritin expression influenced baker's yeast iron metabolism. Soybean seed ferritin H1 (SFerH1) and SFerH2 genes were cloned and expressed in yeast cells. Both soybean ferritins assembled as multimeric complexes, which bound yeast intracellular iron in vivo and, consequently, induced the activation of the genes expressed during iron scarcity. Soybean ferritin protected yeast cells that lacked the Ccc1 vacuolar iron detoxification transporter from toxic iron levels by reducing cellular oxidation, thus allowing growth at high iron concentrations. Interestingly, when simultaneously expressed in ccc1Δ cells, SFerH1 and SFerH2 assembled as heteropolymers, which further increased iron resistance and reduced the oxidative stress produced by excess iron compared to ferritin homopolymer complexes. Finally, soybean ferritin expression led to increased iron accumulation in both wild-type and ccc1Δ yeast cells at certain environmental iron concentrations. IMPORTANCE Iron deficiency is a worldwide nutritional disorder to which women and children are especially vulnerable. A common strategy to combat iron deficiency consists of dietary supplementation with inorganic iron salts, whose bioavailability is very low. Iron-enriched yeasts and cereals are alternative strategies to diminish iron deficiency. Animals and plants possess large ferritin complexes that accumulate, detoxify, or buffer excess cellular iron. However, the yeast Saccharomyces cerevisiae lacks ferritin and uses vacuoles as iron storage organelles. Here, we explored how soybean ferritin expression influenced yeast iron metabolism, confirming that yeasts that express soybean seed ferritin could be explored as a novel strategy to increase dietary iron absorption. PMID:26969708

  12. Dual Mode NOx Sensor: Measuring Both the Accumulated Amount and Instantaneous Level at Low Concentrations

    PubMed Central

    Groß, Andrea; Beulertz, Gregor; Marr, Isabella; Kubinski, David J.; Visser, Jaco H.; Moos, Ralf

    2012-01-01

    The accumulating-type (or integrating-type) NOx sensor principle offers two operation modes to measure low levels of NOx: The direct signal gives the total amount dosed over a time interval and its derivative the instantaneous concentration. With a linear sensor response, no baseline drift, and both response times and recovery times in the range of the gas exchange time of the test bench (5 to 7 s), the integrating sensor is well suited to reliably detect low levels of NOx. Experimental results are presented demonstrating the sensor’s integrating properties for the total amount detection and its sensitivity to both NO and to NO2. We also show the correlation between the derivative of the sensor signal and the known gas concentration. The long-term detection of NOx in the sub-ppm range (e.g., for air quality measurements) is discussed. Additionally, a self-adaption of the measurement range taking advantage of the temperature dependency of the sensitivity is addressed. PMID:22736980

  13. [Concentrations of mercury in ambient air in wastewater irrigated area of Tianjin City and its accumulation in leafy vegetables].

    PubMed

    Zheng, Shun-An; Han, Yun-Lei; Zheng, Xiang-Qun

    2014-11-01

    limit of mercury in food. Spinach appeared to accumulate more mercury than the other four vegetables, in which the median and mean mercury content were both higher than 20 μg x kg(-1). The mercury concentrations in rape, lettuce and allium tuberosum were lower than the standard. Moreover, test results indicated that the Hg content in leafy vegetables was mainly the gaseous mercury through leaf adsorption but not the Hg particulates. This study clearly manifested that there should be a great concern on the pollution risk of both air-and soil borne mercury when cultivating leafy vegetables in long-term wastewater-irrigated area.

  14. Effect of sewage-sludge application on concentrations of higher-brominated diphenyl ethers in soils and earthworms.

    PubMed

    Sellström, Ulla; de Wit, Cynthia A; Lundgren, Nadja; Tysklind, Mats

    2005-12-01

    Polybrominated diphenyl ethers (PBDEs), including octa-decaBDEs, were found in soil and earthworm samples collected in 2000 from three research stations (reference plots and sewage-sludge-amended plots) and two farms (reference and amended/flooded soils) in Sweden. Sewage-sludge amendment at the research stations increased concentrations of all BDE congeners 2- to 13-fold, with the highest increases for BDE-209. Concentrations 100-to 1000-fold higher were seen in contaminated soils at both farms. BDE-209 was the predominant congener in all soils. sigmaPBDE concentrations in worms ranged from 3.1 to 38 000 ng/g lipid weight and were correlated to soil concentrations, including the octa-decaBDEs. Biota-soil accumulation factors declined in the following order: TeBDE > PeBDE > HxBDE > OcBDE > NoBDE > DeBDE, and ranged from 0.3 to 2 for the octa-decaBDEs. Thus, higher-brominated PBDEs, including BDE-209, are bioavailable from soils and accumulate in earthworms, presenting an exposure pathway into the terrestrial food web. High levels found at one farm 20 years after the last use of PBDEs indicate high persistence of PBDEs in soils, including BDE-209. No evidence of photolytic debromination of BDE-209 in soils was seen. PMID:16382926

  15. hsp82 is an essential protein that is required in higher concentrations for growth of cells at higher temperatures.

    PubMed Central

    Borkovich, K A; Farrelly, F W; Finkelstein, D B; Taulien, J; Lindquist, S

    1989-01-01

    hsp82 is one of the most highly conserved and abundantly synthesized heat shock proteins of eucaryotic cells. The yeast Saccharomyces cerevisiae contains two closely related genes in the HSP82 gene family. HSC82 was expressed constitutively at a very high level and was moderately induced by high temperatures. HSP82 was expressed constitutively at a much lower level and was more strongly induced by heat. Site-directed disruption mutations were produced in both genes. Cells homozygous for both mutations did not grow at any temperature. Cells carrying other combinations of the HSP82 and HSC82 mutations grew well at 25 degrees C, but their ability to grow at higher temperatures varied with gene copy number. Thus, HSP82 and HSC82 constitute an essential gene family in yeast cells. Although the two proteins had different patterns of expression, they appeared to have equivalent functions; growth at higher temperatures required higher concentrations of either protein. Biochemical analysis of hsp82 from vertebrate cells suggests that the protein binds to a variety of other cellular proteins, keeping them inactive until they have reached their proper intracellular location or have received the proper activation signal. We speculate that the reason cells require higher concentrations of hsp82 or hsc82 for growth at higher temperatures is to maintain proper levels of complex formation with these other proteins. Images PMID:2674684

  16. Organic and inorganic amendments affect soil concentration and accumulation of cadmium and lead in wheat in calcareous alkaline soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irrigation with untreated effluent in periurban agriculture could result in accumulation and bioconcentrations of cadmium (Cd) and lead (Pb). Different amendments were used to investigate their effect on availability, concentration, and uptake of metals by wheat in texturally different soils. Crop w...

  17. ELEVATED CO2 AND ELEVATED TEMPERATURE AFFECT CARBON AND NITROGEN CONCENTRATIONS BUT NOT ACCUMULATION IN PSEUDOTSUGA MENZIESII SEEDLINGS

    EPA Science Inventory

    To determine the impact of climate change on concentrations and accumulation of C and N in trees, we grew Pseudotsuga menziesii (Mirb.) Franco (Douglas-fir) seedlings treated with ambient or elevated (+180 mol mol-1) CO2, and with ambient or elevated (+3.5 C) temperature for f...

  18. Effects of environmental and physiological variables on the accumulated concentrations of trace metals in the New Zealand cockle Austrovenus stutchburyi.

    PubMed

    Marsden, Islay D; Smith, Brian D; Rainbow, Phillip S

    2014-02-01

    We examined potential causes of variation in trace element accumulation in an estuarine bivalve Austrovenus stutchburyi from two estuarine systems in South Island, New Zealand which differed in their metal contamination and salinity regimes. Concentrations of Ag, As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Ti, V and Zn were measured (ICP-OES) in whole body tissues of bivalves collected from 10 sites, seston collected at high tide (a potential food resource) and in the sediment at the sites. All 13 elements showed a relationship between log bioaccumulated trace element concentration (mgkg(-1) dry weight tissue) and log shell length (mm), either in the whole data set or at least one site (ANCOVA). Growth rates of cockles varied significantly amongst sites. Accumulated soft tissue concentrations of Ag, As, Co and Cr increased with age of cockle, those of Pb and Zn decreased, with no clear age-related trend for the remaining metals (ANCOVA). Shell length was generally a good proxy for age when allowing for any size effect in metal accumulation by the cockle. There was no consistent pattern between the estuarine systems, probably reflecting unidentified contaminant inputs. Following depuration, tissue concentrations decreased significantly for some elements (Fe, Mn, Ti and V), indicating high concentrations of these metals in the gut contents. Trace element concentrations in the seston generally did not correlate with the bivalve tissue concentrations. There were few (Spearman's Rank) correlations between environmental variables at the time of sampling and cockle tissue trace element concentrations. The main sources of variation in bioaccumulated trace metal concentrations in the whole tissues of the cockle are location, shell length and age.

  19. Effects of environmental and physiological variables on the accumulated concentrations of trace metals in the New Zealand cockle Austrovenus stutchburyi.

    PubMed

    Marsden, Islay D; Smith, Brian D; Rainbow, Phillip S

    2014-02-01

    We examined potential causes of variation in trace element accumulation in an estuarine bivalve Austrovenus stutchburyi from two estuarine systems in South Island, New Zealand which differed in their metal contamination and salinity regimes. Concentrations of Ag, As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Ti, V and Zn were measured (ICP-OES) in whole body tissues of bivalves collected from 10 sites, seston collected at high tide (a potential food resource) and in the sediment at the sites. All 13 elements showed a relationship between log bioaccumulated trace element concentration (mgkg(-1) dry weight tissue) and log shell length (mm), either in the whole data set or at least one site (ANCOVA). Growth rates of cockles varied significantly amongst sites. Accumulated soft tissue concentrations of Ag, As, Co and Cr increased with age of cockle, those of Pb and Zn decreased, with no clear age-related trend for the remaining metals (ANCOVA). Shell length was generally a good proxy for age when allowing for any size effect in metal accumulation by the cockle. There was no consistent pattern between the estuarine systems, probably reflecting unidentified contaminant inputs. Following depuration, tissue concentrations decreased significantly for some elements (Fe, Mn, Ti and V), indicating high concentrations of these metals in the gut contents. Trace element concentrations in the seston generally did not correlate with the bivalve tissue concentrations. There were few (Spearman's Rank) correlations between environmental variables at the time of sampling and cockle tissue trace element concentrations. The main sources of variation in bioaccumulated trace metal concentrations in the whole tissues of the cockle are location, shell length and age. PMID:24144937

  20. Re-Setting the Concentration Levels of Students in Higher Education: An Exploratory Study

    ERIC Educational Resources Information Center

    Burke, Lisa A.; Ray, Ruth

    2008-01-01

    Evidence suggests that college students' concentration levels are limited and hard to maintain. Even though relevant in higher education, scant empirical research exists on interventions to "re-set" their concentration during a college lecture. Using a within-subjects design, four active learning interventions are administered across two…

  1. Differences in energy expenditures and growth dilution explain higher PCB concentrations in male summer flounder

    USGS Publications Warehouse

    Madenjian, Charles P.; Jensen, Olaf P.; Rediske, Richard R.; O'Keefe, James P.; Vastano, Anthony R.; Pothoven, Steven A.

    2016-01-01

    Comparison of polychlorinated biphenyl (PCB) concentrations between the sexes of mature fish may reveal important behavioral and physiological differences between the sexes. We determined whole-fish PCB concentrations in 23 female summer flounder Paralichthys dentatus and 27 male summer flounder from New Jersey coastal waters. To investigate the potential for differences in diet or habitat utilization between the sexes, carbon and nitrogen stable isotope ratios were also determined. In 5 of the 23 female summer flounder, PCB concentrations in the somatic tissue and ovaries were determined. In addition, we used bioenergetics modeling to assess the contribution of the growth dilution effect to the observed difference in PCB concentrations between the sexes. Whole-fish PCB concentrations for females and males averaged 87 and 124 ng/g, respectively; thus males were 43% higher in PCB concentration compared with females. Carbon and nitrogen stable isotope ratios did not significantly differ between the sexes, suggesting that diet composition and habitat utilization did not vary between the sexes. Based on PCB determinations in the somatic tissue and ovaries, we predicted that PCB concentration of females would increase by 0.6%, on average, immediately after spawning due to release of eggs. Thus, the change in PCB concentration due to release of eggs did not explain the higher PCB concentrations observed in males. Bioenergetics modeling results indicated that the growth dilution effect could account for males being 19% higher in PCB concentration compared with females. Thus, the bulk of the observed difference in PCB concentrations between the sexes was not explained by growth dilution. We concluded that a higher rate of energy expenditure in males, stemming from greater activity and a greater resting metabolic rate, was most likely the primary driver for the observed difference in PCB concentrations between the sexes.

  2. Differences in Energy Expenditures and Growth Dilution Explain Higher PCB Concentrations in Male Summer Flounder.

    PubMed

    Madenjian, Charles P; Jensen, Olaf P; Rediske, Richard R; O'Keefe, James P; Vastano, Anthony R; Pothoven, Steven A

    2016-01-01

    Comparison of polychlorinated biphenyl (PCB) concentrations between the sexes of mature fish may reveal important behavioral and physiological differences between the sexes. We determined whole-fish PCB concentrations in 23 female summer flounder Paralichthys dentatus and 27 male summer flounder from New Jersey coastal waters. To investigate the potential for differences in diet or habitat utilization between the sexes, carbon and nitrogen stable isotope ratios were also determined. In 5 of the 23 female summer flounder, PCB concentrations in the somatic tissue and ovaries were determined. In addition, we used bioenergetics modeling to assess the contribution of the growth dilution effect to the observed difference in PCB concentrations between the sexes. Whole-fish PCB concentrations for females and males averaged 87 and 124 ng/g, respectively; thus males were 43% higher in PCB concentration compared with females. Carbon and nitrogen stable isotope ratios did not significantly differ between the sexes, suggesting that diet composition and habitat utilization did not vary between the sexes. Based on PCB determinations in the somatic tissue and ovaries, we predicted that PCB concentration of females would increase by 0.6%, on average, immediately after spawning due to release of eggs. Thus, the change in PCB concentration due to release of eggs did not explain the higher PCB concentrations observed in males. Bioenergetics modeling results indicated that the growth dilution effect could account for males being 19% higher in PCB concentration compared with females. Thus, the bulk of the observed difference in PCB concentrations between the sexes was not explained by growth dilution. We concluded that a higher rate of energy expenditure in males, stemming from greater activity and a greater resting metabolic rate, was most likely the primary driver for the observed difference in PCB concentrations between the sexes.

  3. Differences in Energy Expenditures and Growth Dilution Explain Higher PCB Concentrations in Male Summer Flounder

    PubMed Central

    Madenjian, Charles P.; Jensen, Olaf P.; Rediske, Richard R.; O’Keefe, James P.; Vastano, Anthony R.; Pothoven, Steven A.

    2016-01-01

    Comparison of polychlorinated biphenyl (PCB) concentrations between the sexes of mature fish may reveal important behavioral and physiological differences between the sexes. We determined whole-fish PCB concentrations in 23 female summer flounder Paralichthys dentatus and 27 male summer flounder from New Jersey coastal waters. To investigate the potential for differences in diet or habitat utilization between the sexes, carbon and nitrogen stable isotope ratios were also determined. In 5 of the 23 female summer flounder, PCB concentrations in the somatic tissue and ovaries were determined. In addition, we used bioenergetics modeling to assess the contribution of the growth dilution effect to the observed difference in PCB concentrations between the sexes. Whole-fish PCB concentrations for females and males averaged 87 and 124 ng/g, respectively; thus males were 43% higher in PCB concentration compared with females. Carbon and nitrogen stable isotope ratios did not significantly differ between the sexes, suggesting that diet composition and habitat utilization did not vary between the sexes. Based on PCB determinations in the somatic tissue and ovaries, we predicted that PCB concentration of females would increase by 0.6%, on average, immediately after spawning due to release of eggs. Thus, the change in PCB concentration due to release of eggs did not explain the higher PCB concentrations observed in males. Bioenergetics modeling results indicated that the growth dilution effect could account for males being 19% higher in PCB concentration compared with females. Thus, the bulk of the observed difference in PCB concentrations between the sexes was not explained by growth dilution. We concluded that a higher rate of energy expenditure in males, stemming from greater activity and a greater resting metabolic rate, was most likely the primary driver for the observed difference in PCB concentrations between the sexes. PMID:26794728

  4. Differences in Energy Expenditures and Growth Dilution Explain Higher PCB Concentrations in Male Summer Flounder.

    PubMed

    Madenjian, Charles P; Jensen, Olaf P; Rediske, Richard R; O'Keefe, James P; Vastano, Anthony R; Pothoven, Steven A

    2016-01-01

    Comparison of polychlorinated biphenyl (PCB) concentrations between the sexes of mature fish may reveal important behavioral and physiological differences between the sexes. We determined whole-fish PCB concentrations in 23 female summer flounder Paralichthys dentatus and 27 male summer flounder from New Jersey coastal waters. To investigate the potential for differences in diet or habitat utilization between the sexes, carbon and nitrogen stable isotope ratios were also determined. In 5 of the 23 female summer flounder, PCB concentrations in the somatic tissue and ovaries were determined. In addition, we used bioenergetics modeling to assess the contribution of the growth dilution effect to the observed difference in PCB concentrations between the sexes. Whole-fish PCB concentrations for females and males averaged 87 and 124 ng/g, respectively; thus males were 43% higher in PCB concentration compared with females. Carbon and nitrogen stable isotope ratios did not significantly differ between the sexes, suggesting that diet composition and habitat utilization did not vary between the sexes. Based on PCB determinations in the somatic tissue and ovaries, we predicted that PCB concentration of females would increase by 0.6%, on average, immediately after spawning due to release of eggs. Thus, the change in PCB concentration due to release of eggs did not explain the higher PCB concentrations observed in males. Bioenergetics modeling results indicated that the growth dilution effect could account for males being 19% higher in PCB concentration compared with females. Thus, the bulk of the observed difference in PCB concentrations between the sexes was not explained by growth dilution. We concluded that a higher rate of energy expenditure in males, stemming from greater activity and a greater resting metabolic rate, was most likely the primary driver for the observed difference in PCB concentrations between the sexes. PMID:26794728

  5. Differences in the accumulated metal concentrations in two epigeic earthworm species (Lumbricus rubellus and Dendrodrilus rubidus) living in contaminated soils

    SciTech Connect

    Morgan, J.E.; Morgan, A.J. )

    1991-08-01

    Lumbricus rubellus and Denrodrilus rubidus are acid-tolerant epigeic species, which are often the only species inhabiting the poorly vegetated and heavily contaminated soils associated with many abandoned mine sites. Although both species probably consume similar food materials, observations on worms collected from acidic and calcareous mine sites indicate that they accumulate significantly different metal concentrations in their tissues: the larger L. rubellus accumulates more Zn and Ca, but less Pb and Cd than D. rubidus. The aim of the present study was to analyze these two epigeic species sampled from ten diverse sites to determine whether the inter-species differences in relative metal accumulation is a general feature of these sympatrics.

  6. Optimization of macroelement concentrations, pH and osmolarity for triacylglycerol accumulation in Rhodococcus opacus strain PD630

    PubMed Central

    2013-01-01

    The refinement of biodiesel or renewable diesel from bacterial lipids has a great potential to make a contribution for energy production in the future. This study provides new data concerning suitable nutrient concentrations for cultivation of the Gram-positive Rhodococcus opacus PD630, which is able to accumulate large amounts of lipids during nitrogen limitation. Enhanced concentrations of magnesium have been shown to increase the final optical density and the lipid content of the cells. Elevated phosphate concentrations slowed down the onset of the accumulation phase, without a clear effect on the final optical density and the cell’s lipid content. A robust growth of R. opacus was possible in the presence of ammonium concentrations of up to 1.4 g l-1 and sucrose concentrations of up to 240 g l-1, with an optimum regarding growth and lipid storage observed in the range of 0.2 to 0.4 g l-1 ammonium and 20 to 40 g l-1 sucrose, respectively. Moreover, R. opacus showed tolerance to high salt concentrations. PMID:23855965

  7. Vacuolar accumulation of heavy metals in Datura cultured cells is metal concentration dependent

    SciTech Connect

    Krotz, R.M.; Wagner, G.J.

    1987-04-01

    Vacuolar-extravacuolar compartmentation studies were performed to determine if the vacuole serves as an accumulation site for Cd, Zn, and Ni, after growth of Datura cultured cells in trace and high levels of these metals. After 3 to 4 days growth with 0.12 ..mu..M Cd or 0.02 ..mu..M Ni (radiolabeled) no evidence was obtained for vacuolar accumulation of these metals. In contrast, growth with 30 or 45 ..mu..M Cd, 11 ..mu..M Ni (with or without trace radiolabel), or 300 and 500 ..mu..M Zn resulted in isolated vacuoles which were enriched in metal. Compartmentation after exposure to low levels of Zn and also Cu is being investigated as is the subcellular site(s) of Cd-binding peptide formed during growth in high Cd. The hypothesis that Zn is accumulated as vacuolar organic acid salts is being tested directly because no evidence was found for formation of substantial ligand of Cd-peptide in response to Zn exposure.

  8. Accumulation of radionuclides by fish in relation to presence of bottom deposits and concentration of microelements in the water

    SciTech Connect

    Katkov, A.E.

    1980-03-01

    This paper is devoted to determination of the special features of accumulation of hydrobionts of radionuclides desorbed from the bottom in comparison with the accumulation of radionuclides entering the water directly. The investigations were stimulated by published information indicating that bottom deposits can shield bottom bionts against the uptake of some radionuclides and that the uptake of radionuclides by plants is enhanced by the presence of bottom deposits. We also sum up the results of experimental investigations of concentration factors (CF) for nuclides in relation to their concentration in water to obtain a more accurate picture of the role of mineralization in the exchange of microelements. The experiments were conducted on adult (6 to 8 years old) goldfish (Carassius carassius) from a body of water containing fresh water with a total mineral content of 0.06 g/liter.

  9. Heavy metal accumulation in Diplodus annularis, Liza aurata, and Solea vulgaris relevant to their concentration in water and sediment from the southwestern Mediterranean (coast of Sfax).

    PubMed

    Ben Salem, Zohra; Ayadi, Habib

    2016-07-01

    The concentrations of heavy metals (Cd, Cu, Fe, Pb, Ni, and Zn) were measured in the liver, gills, and muscle of Solea vulgaris, Liza aurata, and Diplodus annularis, collected from the south coast of Sfax (Gabes Gulf, southwestern Mediterranean). The concentrations of heavy metals in water exhibited the following decreasing order (expressed in μg l(-1)): Fe > Ni > Zn > Cu > Pb > Cd whereas the trend is somewhat different in sediments (mg kg(-1) D.W.) Fe > Zn > Pb > Ni > Cu > Cd. The levels of heavy metals varied significantly among fish species and tissues. Heavy metal levels were found generally higher in the liver and gills than the muscle in all species. The liver was the target organ for Cd, Cu, Fe, Ni, and Zn accumulation. Nickel and lead, however, exhibited their highest concentrations in the gills. The three studied fishes showed a difference in metals accumulation decreasing in following order S. vulgaris > D. annularis > L. aurata. Solea vulgaris with the highest TFwater, TFsediment, and metal concentrations in tissues would be considered as a potential bio-indicator in the south coast of Sfax for the assessment of environmental pollution status. Comparative studies with Luza zone indicate considerable bioaccumulation of heavy metals (Pb and Zn) in the various tissues of fish samples of the south coast of Sfax.

  10. Relationship of cadmium accumulation to zinc or copper concentration in horse liver and kidney

    SciTech Connect

    Koizumi, Naoko; Ninomiya, Ruriko; Fujita, Daisuke; Tsukamoto, Toshiyuki ); Inoue, Yoshiki )

    1989-06-01

    The concentrations of Cd, Zn, Cu, and metallothionein (MT) in the liver, renal cortex, and renal medulla were determined in 24 male and 15 female younger thoroughbreds (age 27 to 97 months) and two old male horses (age 154 months and 190 months). High correlations were found between Zn and MT in the liver, between Cd and MT in the renal cortex, and between Cd and Zn in the renal cortex, while the correlation between Cd and MT in the liver was low. In the renal medulla, high correlations were found between Cd and Zn, between Zn and Cu, and between Cd and Cu. Therefore, in the liver, the MT concentration is the most highly correlated with the Zn concentration and is not correlated with the Cd concentration unless artificially exposed to Cd. In the renal cortex, the MT and Cd concentrations are very highly correlated with each other. The Zn concentration is about 20 {mu}/g when the Cd concentration in the renal cortex is the lowest.

  11. Distribution of the concentration of heavy metals associated with the sediment particles accumulated on road surfaces.

    PubMed

    Zafra, C A; Temprano, J; Tejero, I

    2011-07-01

    The heavy metal pollution caused by road run-off water constitutes a problem in urban areas. The metallic load associated with road sediment must be determined in order to study its impact in drainage systems and receiving waters, and to perfect the design of prevention systems. This paper presents data regarding the sediment collected on road surfaces in the city of Torrelavega (northern Spain) during a period of 65 days (132 samples). Two sample types were collected: vacuum-dried samples and those swept up following vacuuming. The sediment loading (g m(-2)), particle size distribution (63-2800 microm) and heavy metal concentrations were determined. The data showed that the concentration of heavy metals tends to increase with the reduction in the particle diameter (exponential tendency). The concentrations ofPb, Zn, Cu, Cr, Ni, Cd, Fe, Mn and Co in the size fraction <63 microm were 350, 630, 124, 57, 56, 38, 3231, 374 and 51 mg kg(-1), respectively (average traffic density: 3800 vehicles day(-1)). By increasing the residence time of the sediment, the concentration increases, whereas the ratio of the concentration between the different size fractions decreases. The concentration across the road diminishes when the distance between the roadway and the sampling siteincreases; when the distance increases, the ratio between size fractions for heavy metal concentrations increases. Finally, the main sources of heavy metals are the particles detached by braking (brake pads) and tyre wear (rubber), and are associated with particle sizes <125 microm.

  12. Preexposure to low ozone concentrations does not diminish the pulmonary function response on exposure to higher ozone concentrations

    SciTech Connect

    Gliner, J.A.; Horvath, S.M.; Folinsbee, L.J.

    1983-01-01

    To determine whether persons repeatedly exposed to low ozone concentrations would demonstrate a diminished responsivity, as a result of adaptation or desensitization, when subsequently exposed to a higher ozone concentration, we performed the following study. Respiratory sensitivity (pulmonary function response) to 2 h of exposure to 0.42 or 0.50 ppm ozone (acute exposure) was determined 3 months before or 6 to 8 wk after the study. Twenty-one subjects (8 men, 13 women) were exposed for 2 h or 5 consecutive days to filtered air, 0.20, 0.20, 0.20, and 0.42 to 0.50 ppm ozone, respectively. There were no significant differences between the responses of men and women to ozone. Subjects were divided into a sensitive group (greater than 20% drop in FEV1) and a nonsensitive group (less than 10% drop in FEV1) on the basis of their responses to the acute exposure. Neither the overall group nor the nonsensitive group showed a significant response to 0.20 ppm. Sensitive subjects (n . 9) showed small but significant decreases in FEV1 on exposure to 0.20 ppm. The predominant finding was that the 3 days of preexposure to 0.20 ppm ozone had no effect on the response to 0.42 or 0.50 ppm ozone on the fourth day (when compared with the previous acute exposure to 0.42 or 0.50 ppm). We conclude that subjects repeatedly (3 times) exposed to a low (0.20 ppm) concentration of ozone do not demonstrate a pulmonary function adaptation or desensitization on a subsequent exposure to a higher (0.42 or 0.50 ppm) ozone concentration.

  13. Capture and accumulation of perchlorate in lettuce. Effect of genotype, temperature, perchlorate concentration, and competition with anions.

    PubMed

    Calderón, Raúl; Palma, Paulina; Parker, David; Escudey, Mauricio

    2014-09-01

    Various studies have evaluated the accumulation of ClO4(-) in lettuce (Lactuca sativa), but very few have dealt with the variables that can interfere with its capture. The present study evaluates the transfer of ClO4(-) in two L. sativa varieties: butter head (L. sativa var. capitata) and cos lettuce (L. sativa var. crispa) under hydroponic conditions. The ClO4(-) concentrations used correspond to levels (1 and 2mgL(-1)), measured in irrigation water in the Iquique region in the north of Chile. Results indicate that the capture of ClO4(-) is dependent on its concentration, lettuce genotype, and temperature. The butter head variety accumulates the highest perchlorate concentrations. Anion competition involving NO3(-) (16 and 48mM), Cl(-) (23 and 56mM), and SO4(2-) (10 and 20mM) was evaluated, being NO3(-) (48mM), the most significant competition reducing the concentration of ClO4(-) in tissues of L. sativa varieties.

  14. POSSIBLE RAMIFICATIONS OF HIGHER MERCURY CONCENTRATIONS IN FILLET TISSUE OF SKINNIER FISH

    EPA Science Inventory

    Mercury concentrations were found to be statistically higher in the fillet tissue of the skinnier individuals of a fish species (striped bass) that was experiencing starvation when collected from Lake Mead, which is located on the Arizona-Nevada border. This is considered a conse...

  15. Effects of elevated CO2 concentrations and fly ash amended soils on trace element accumulation and translocation among roots, stems and seeds of Glycine max (L.) Merr.

    PubMed

    Rodriguez, J H; Klumpp, A; Fangmeier, A; Pignata, M L

    2011-03-15

    The carbon dioxide (CO(2)) levels of the global atmosphere and the emissions of heavy metals have risen in recent decades, and these increases are expected to produce an impact on crops and thereby affect yield and food safety. In this study, the effects of elevated CO(2) and fly ash amended soils on trace element accumulation and translocation in the root, stem and seed compartments in soybean [Glycine max (L.) Merr.] were evaluated. Soybean plants grown in fly ash (FA) amended soil (0, 1, 10, 15, and 25% FA) at two CO(2) regimes (400 and 600 ppm) in controlled environmental chambers were analyzed at the maturity stage for their trace element contents. The concentrations of Br, Co, Cu, Fe, Mn, Ni, Pb and Zn in roots, stems and seeds in soybeans were investigated and their potential risk to the health of consumers was estimated. The results showed that high levels of CO(2) and lower concentrations of FA in soils were associated with an increase in biomass. For all the elements analyzed except Pb, their accumulation in soybean plants was higher at elevated CO(2) than at ambient concentrations. In most treatments, the highest concentrations of Br, Co, Cu, Fe, Mn, and Pb were found in the roots, with a strong combined effect of elevated CO(2) and 1% of FA amended soils on Pb accumulation (above maximum permitted levels) and translocation to seeds being observed. In relation to non-carcinogenic risks, target hazard quotients (TQHs) were significant in a Chinese individual for Mn, Fe and Pb. Also, the increased health risk due to the added effects of the trace elements studied was significant for Chinese consumers. According to these results, soybean plants grown for human consumption under future conditions of elevated CO(2) and FA amended soils may represent a toxicological hazard. Therefore, more research should be carried out with respect to food consumption (plants and animals) under these conditions and their consequences for human health.

  16. Serum creatinine concentration at the onset of uremia: higher levels in black males.

    PubMed

    Abuelo, J G; Shemin, D; Chazan, J A

    1992-06-01

    We compared serum creatinine and blood urea nitrogen concentrations, estimated creatinine clearances and frequency of uremic symptoms at the start of chronic hemodialysis in all 20 black and 179 white males treated between 1969 and 1983. Serum creatinine concentrations were significantly higher in black males (16.5 +/- 5.9 mg/dl) than in white males (11.7 +/- 4.7 mg/dl; p = 0.016). There were no significant differences in blood urea nitrogen concentration, estimated creatinine clearance and frequency of uremic symptoms between the two groups. Blood urea nitrogen to serum creatinine ratios were lower in black males, (7.3 +/- 1.9) than in white males (11.4 +/- 3.8; p = 0.0001), and only one black male had a ratio greater than 10 compared to 60% of whites. We concluded that black males tend to have higher serum creatinine concentrations than white males at the onset of uremic symptoms, and that higher striated muscle creatinine production in black males and not lower renal function may be the cause.

  17. Arbuscular mycorrhiza increase artemisinin accumulation in Artemisia annua by higher expression of key biosynthesis genes via enhanced jasmonic acid levels.

    PubMed

    Mandal, Shantanu; Upadhyay, Shivangi; Wajid, Saima; Ram, Mauji; Jain, Dharam Chand; Singh, Ved Pal; Abdin, Malik Zainul; Kapoor, Rupam

    2015-07-01

    It is becoming increasingly evident that the formation of arbuscular mycorrhiza (AM) enhances secondary metabolite production in shoots. Despite mounting evidence, relatively little is known about the underlying mechanisms. This study suggests that increase in artemisinin concentration in Artemisia annua colonized by Rhizophagus intraradices is due to altered trichome density as well as transcriptional patterns that are mediated via enhanced jasmonic acid (JA) levels. Mycorrhizal (M) plants had higher JA levels in leaf tissue that may be due to induction of an allene oxidase synthase gene (AOS), encoding one of the key enzymes for JA production. Non-mycorrhizal (NM) plants were exogenously supplied with a range of methyl jasmonic acid concentrations. When leaves of NM and M plants with similar levels of endogenous JA were compared, these matched closely in terms of shoot trichome density, artemisinin concentration, and transcript profile of artemisinin biosynthesis genes. Mycorrhization increased artemisinin levels by increasing glandular trichome density and transcriptional activation of artemisinin biosynthesis genes. Transcriptional analysis of some rate-limiting enzymes of mevalonate and methyl erythritol phosphate (MEP) pathways revealed that AM increases isoprenoids by induction of the MEP pathway. A decline in artemisinin concentration in shoots of NM and M plants treated with ibuprofen (an inhibitor of JA biosynthesis) further confirmed the implication of JA in the mechanism of artemisinin production.

  18. Acute systemic accumulation of acrolein in mice by inhalation at a concentration similar to that in cigarette smoke

    PubMed Central

    Tully, Melissa; Zheng, Lingxing; Acosta, Glen; Tian, Ran; Shi, Riyi

    2015-01-01

    Cigarette smoke is an important environmental factor associated with a wide array of public health concerns. Acrolein, a component of tobacco smoke and a known toxin to various cell types, may be a key pathological factor mediating the adverse effects linked with tobacco smoke. Although acrolein is known to accumulate in the respiratory system after acute nasal exposure, it is not clear if it accumulates systemically, and less is known in the nervous system. The aim of this study was to assess the degree of acrolein accumulation in the circulation and in the spinal cord following acute acrolein inhalation in mice. Using a laboratory-fabricated inhalation chamber, we found elevated urinary 3-HPMA, an acrolein metabolite, and increased acrolein adducts in the spinal cord after weeks of nasal exposure to acrolein at a concentration similar to that in tobacco smoke. The data indicated that acrolein is absorbed into the circulatory system and some enters the nervous system. It is expected that these findings may facilitate further studies to probe the pathological role of acrolein in the nervous system resulting from smoke and other external sources. PMID:25446876

  19. Acute systemic accumulation of acrolein in mice by inhalation at a concentration similar to that in cigarette smoke.

    PubMed

    Tully, Melissa; Zheng, Lingxing; Acosta, Glen; Tian, Ran; Shi, Riyi

    2014-12-01

    Cigarette smoke is an important environmental factor associated with a wide array of public health concerns. Acrolein, a component of tobacco smoke and a known toxin to various cell types, may be a key pathological factor mediating the adverse effects linked with tobacco smoke. Although acrolein is known to accumulate in the respiratory system after acute nasal exposure, it is not clear if it accumulates systemically, and less is known in the nervous system. The aim of this study was to assess the degree of acrolein accumulation in the circulation and in the spinal cord following acute acrolein inhalation in mice. Using a laboratory-fabricated inhalation chamber, we found elevated urinary 3-HPMA, an acrolein metabolite, and increased acrolein adducts in the spinal cord after weeks of nasal exposure to acrolein at a concentration similar to that in tobacco smoke. The data indicated that acrolein is absorbed into the circulatory system and some enters the nervous system. It is expected that these findings may facilitate further studies to probe the pathological role of acrolein in the nervous system resulting from smoke and other external sources.

  20. Effects of high Zn and Pb concentrations on Phragmites australis (Cav.) Trin. Ex. Steudel: Photosynthetic performance and metal accumulation capacity under controlled conditions.

    PubMed

    Bernardini, A; Salvatori, E; Guerrini, V; Fusaro, L; Canepari, S; Manes, F

    2016-01-01

    The response of Phragmites australis (Cav.) Trin. Ex. Steudel to zinc (Zn) and lead (Pb) was studied separately in two hydroponic tests, during a three weeks experiment. The effects on ecophysiology and biomass partitioning were evaluated during the metal treatments and at the recovery, and total metal content and accumulation capacity in different plant organs were assessed. Zn and Pb had different effects on the overall measured parameters, highlighting different mechanism of action. In particular, Zn concentration was higher in roots and, being a micronutrient, it was translocated into leaves, producing a reduction of assimilation rate, stomatal conductance (-71.9 and -81.3% respect to the control plant respectively), and a strong down regulation of photosystems functionality both at PSII and PSI level. Otherwise, Pb was accumulated mainly in the more lignified tissue such as rhizomes, with slightly effect on gas exchange. Chlorophyll a fluorescence highlighted that Pb inhibits the electron transfer process at the PSI donor side, without recovery after the removal of the metal stress. Despite these physiological limitations, P. australis showed a high capacity to accumulate both metals, and only slight reduction of biomass, being therefore a suitable species for phytoremediation interventions.

  1. Trace metal concentrations are higher in cartilage than in bones of scaup and pochard wintering in Poland.

    PubMed

    Kalisińska, Elzbieta; Salicki, Wiesław; Kavetska, Katarzyna M; Ligocki, Marek

    2007-12-15

    Bones and cartilage of two species of diving ducks: the scaup Aythya marila (n=24) and the pochard A. ferina (n=24) were studied. Scaup is protected in Poland where it spends only the winter, while pochard is a game bird, abundant and breeding in Poland. In winter, the two species form large flocks off the southern coast of the Baltic, particularly in the Szczecin Lagoon where they were collected for this study. The bones and cartilage (trachea) were assayed for concentrations (dry weight-based) of three essential metals: iron (Fe), copper (Cu), and zinc (Zn); concentrations of the two toxic metals: lead (Pb) and cadmium (Cd) were assayed as well. These hard tissues of the two species showed the following order of metal concentrations Zn>Fe>Pb>Cu>Cd. In scaup and pochard bones, the respective geometric mean concentrations of Zn, Fe, Pb, Cu, and Cd were 94.4 and 102.0; 20.2 and 24.7; 6.2 and 9.6; 0.19 and 0.26; 0.114 and 0.162 mg/kg. The levels of all the metals in cartilage (Zn 149.1 and 165.8; Fe 58.4 and 116.3; Pb 10.6 and 14.9; Cu 1.41 and 3.31; Cd 0.144 and 0.175 mg/kg, respectively) were higher than in the bones of A. marila and A. ferina. However, statistically significant differences were found in respect to the essential metals only (Zn, Fe, Cu). The inter-species comparisons showed the two species to differ in their cartilage concentrations of Fe, Cu, Zn, and Cd and in their bone concentrations of Pb and Cd. In each case, the pochard exhibited higher concentrations of metals. This study showed distinct differences between trace element accumulation by two heavily mineralised avian body parts: leg bones (tarsometatarsus) and cartilage (trachea). The results are in agreement with data reported by other workers who analysed trace metals in cartilaginous and bone components of the femoral head in homoiotherm vertebrates, including humans. Therefore it is important that intra- and inter-species comparisons of hard biological components be based on corresponding

  2. Effects of lead concentration and accumulation on the performance and microbial community of aerobic granular sludge in sequencing batch reactors.

    PubMed

    Tan, Guangcai; Xu, Nan; Liu, Yong; Hao, Hongshan; Sun, Weiling

    2016-11-01

    The present study investigated the effects of lead on the morphological structure, physical and chemical properties, wastewater treatment performance and microbial community structure of aerobic granular sludge (AGS) in sequencing batch reactors (SBRs). The results showed that at Pb(2+) concentration of 1 mg/L, the mixed liquid suspended solids decreased, the settling velocity increased and the sludge volume index increased sharply. Meanwhile, AGS began to disintegrate and show an irregular shape. In terms of wastewater treatment in an SBR, the phosphorus removal rate was affected only until the Pb(2+) concentration was up to 1 mg/L. The [Formula: see text] removal efficiency began to decline when the Pb(2+) concentration increased to 6 mg/L, while the removal of chemical oxygen demand increased slightly within the Pb(2+) concentration range of 1-6 mg/L. Significant changes were observed in the microbial community structure, especially the dominant bacteria. Compared to the Pb(2+) accumulation on the sludge, the Pb(2+) concentration in the aqueous phase played a more important role in the performance and microbial community of AGS in SBRs. PMID:27012589

  3. Collapse of higher-order solute concentration moments in groundwater transport

    NASA Astrophysics Data System (ADS)

    Srzic, Veljko; Andricevic, Roko; Gotovac, Hrvoje; Cvetkovic, Vladimir

    2013-08-01

    In this paper, we use numerical simulations based on a Lagrangian framework to study contaminant transport through highly heterogeneous porous media due to advection and local diffusion (under local diffusion, we assume coupled effect of mechanical dispersion and molecular diffusion). The analysis of the concentration field is done for the case of a two-dimensional hydraulic conductivity domain representing the aquifer, with three log-conductivity structures that differ in spatial correlation. In addition to different conductivity structures, we focus our investigation on mild and highly heterogeneous porous media characterized by the values of hydraulic log-conductivity variance >(σY2>) being equal to 1 and 8. In the concentration moment analysis, we show that a linear relationship exists between higher-order to second-order normalized concentration moments on a log-log scale up to the fourth-order moment. This leads to the important finding that moments of a higher than the second order can be derived based on information about the first two concentration moments only. Such a property has been observed previously for boundary-layer water channels, wind tunnels, and turbulent diffusion in open terrain and laboratory experiments. Normalized moments are shown to collapse for different types of hydraulic conductivity structures, Peclet (Pe) numbers and σY2 values. In the case of local diffusion absence, a linear log-log relationship is derived analytically and is set as a lower limit. The deviation from the lower limit is explained to be predominantly caused by the local diffusion, which needs time to evolve. In the case of local diffusion presence, we define the moment deriving function (MDF) to describe the linear log-log relationship between higher-order concentration moments to the second-order normalized one. Finally, the comparison between numerical results and those obtained from the Columbus Air Force Base Macrodispersion Experiment (MADE 1) is used to

  4. Higher serum 25-hydroxyvitamin D concentrations are related to a reduced risk of depression.

    PubMed

    Jääskeläinen, Tuija; Knekt, Paul; Suvisaari, Jaana; Männistö, Satu; Partonen, Timo; Sääksjärvi, Katri; Kaartinen, Niina E; Kanerva, Noora; Lindfors, Olavi

    2015-05-14

    Vitamin D has been suggested to protect against depression, but epidemiological evidence is scarce. The present study investigated the relationship of serum 25-hydroxyvitamin D (25(OH)D) with the prevalence of depressive and anxiety disorders. The study population consisted of a representative sample of Finnish men and women aged 30-79 years from the Health 2000 Survey. The sample included 5371 individuals, of which 354 were diagnosed with depressive disorder and 222 with anxiety disorder. Serum 25(OH)D concentration was determined from frozen samples. In a cross-sectional study, a total of four indicators of depression and one indicator of anxiety were used as dependent variables. Serum 25(OH)D was the risk factor of interest, and logistic models used further included sociodemographic and lifestyle variables as well as indicators of metabolic health as confounding and/or effect-modifying factors. The population attributable fraction (PAF) was estimated. Individuals with higher serum 25(OH)D concentrations showed a reduced risk of depression. The relative odds between the highest and lowest quartiles was 0.65 (95% CI 0.46, 0.93; P for trend = 0.006) after adjustment for sociodemographic, lifestyle and metabolic factors. Higher serum 25(OH)D concentrations were associated with a lower prevalence of depressive disorder especially among men, younger, divorced and those who had an unhealthy lifestyle or suffered from the metabolic syndrome. The PAF was estimated to be 19% for depression when serum 25(OH)D concentration was at least 50 nmol/l. These results support the hypothesis that higher serum 25(OH)D concentrations protect against depression even after adjustment for a large number of sociodemographic, lifestyle and metabolic factors. Large-scale prospective studies are needed to confirm this finding.

  5. Increased palmitate intake: higher acylcarnitine concentrations without impaired progression of β-oxidation1[S

    PubMed Central

    Kien, C. Lawrence; Matthews, Dwight E.; Poynter, Matthew E.; Bunn, Janice Y.; Fukagawa, Naomi K.; Crain, Karen I.; Ebenstein, David B.; Tarleton, Emily K.; Stevens, Robert D.; Koves, Timothy R.; Muoio, Deborah M.

    2015-01-01

    Palmitic acid (PA) is associated with higher blood concentrations of medium-chain acylcarnitines (MCACs), and we hypothesized that PA may inhibit progression of FA β-oxidation. Using a cross-over design, 17 adults were fed high PA (HPA) and low PA/high oleic acid (HOA) diets, each for 3 weeks. The [1-13C]PA and [13-13C]PA tracers were administered with food in random order with each diet, and we assessed PA oxidation (PA OX) and serum AC concentration to determine whether a higher PA intake promoted incomplete PA OX. Dietary PA was completely oxidized during the HOA diet, but only about 40% was oxidized during the HPA diet. The [13-13C]PA/[1-13C]PA ratio of PA OX had an approximate value of 1.0 for either diet, but the ratio of the serum concentrations of MCACs to long-chain ACs (LCACs) was significantly higher during the HPA diet. Thus, direct measurement of PA OX did not confirm that the HPA diet caused incomplete PA OX, despite the modest, but statistically significant, increase in the ratio of MCACs to LCACs in blood. PMID:26156077

  6. Increased palmitate intake: higher acylcarnitine concentrations without impaired progression of β-oxidation.

    PubMed

    Kien, C Lawrence; Matthews, Dwight E; Poynter, Matthew E; Bunn, Janice Y; Fukagawa, Naomi K; Crain, Karen I; Ebenstein, David B; Tarleton, Emily K; Stevens, Robert D; Koves, Timothy R; Muoio, Deborah M

    2015-09-01

    Palmitic acid (PA) is associated with higher blood concentrations of medium-chain acylcarnitines (MCACs), and we hypothesized that PA may inhibit progression of FA β-oxidation. Using a cross-over design, 17 adults were fed high PA (HPA) and low PA/high oleic acid (HOA) diets, each for 3 weeks. The [1-(13)C]PA and [13-(13)C]PA tracers were administered with food in random order with each diet, and we assessed PA oxidation (PA OX) and serum AC concentration to determine whether a higher PA intake promoted incomplete PA OX. Dietary PA was completely oxidized during the HOA diet, but only about 40% was oxidized during the HPA diet. The [13-(13)C]PA/[1-(13)C]PA ratio of PA OX had an approximate value of 1.0 for either diet, but the ratio of the serum concentrations of MCACs to long-chain ACs (LCACs) was significantly higher during the HPA diet. Thus, direct measurement of PA OX did not confirm that the HPA diet caused incomplete PA OX, despite the modest, but statistically significant, increase in the ratio of MCACs to LCACs in blood.

  7. Growth, compatible solute and salt accumulation of five mycorrhizal fungal species grown over a range of NaCl concentrations.

    PubMed

    Bois, G; Bertrand, A; Piché, Y; Fung, M; Khasa, D P

    2006-03-01

    The oil sand industry in northeastern Alberta produces vast areas of severely disturbed land. The sodicity of these anthropic soils is one of the principal constraints that impede their revegetation. Previous in vitro studies have shown that the ectomycorrhizal fungi Laccaria bicolor (Maire) Orton UAMH 8232 and Hebeloma crustuliniforme (Bull) Quel. UAMH 5247 have certain salt-resistant traits and thus are candidate species for the inoculation of tree seedlings to be outplanted on salt-affected soil. In this study, the in vitro development of these fungi was compared to that of three mycorrhizal fungi [Suillus tomentosus (Kauff.) Sing., Snell and Dick; Hymenoscyphus sp. and Phialocephala sp.] isolated from a sodic site created by Syncrude Canada Ltd. Their growth, osmotica and Na/Cl contents were assessed over a range (0, 50, 100, 200 mM) of NaCl concentrations. After 21 days, the two ascomycetes (Hymenoscyphus sp. and Phialocephala sp.) were shown to be more resistant to the NaCl treatments than the three basidiomycete species. Of the basidiomycetes, L. bicolor was the most sensitive to NaCl stress, while H. crustuliniforme showed greater water stress resistance, and the S. tomentosus isolate exhibited greater Na and Cl filtering capacities and had a better biomass yield over the NaCl gradient tested. Both ascomycetes used mechanisms other than carbohydrate accumulation to palliate NaCl stress. While the Hymenoscyphus isolate accumulated proline in response to NaCl treatments, the darker Phialocephala isolate may have used compounds such as melanin. The basidiomycete species accumulated mainly mannitol and/or proline in response to increasing concentrations of NaCl.

  8. Shallow Sediment Trace Metal Concentrations and Short-Term Accumulation Rates in the Neponset River Estuary, Massachusetts, USA

    NASA Astrophysics Data System (ADS)

    Spencer, J. R.; Zhu, J.; Olsen, C. R.

    2010-12-01

    The Neponset River estuary is a small estuary that drains into the Boston Harbor on the east coast of the United States. It is also a highly urbanized estuary and has a long history of urban development over 450 years. In July 2006, six sediment cores were collected in the Neponset River estuary to examine particle dynamics and sediment accumulation via radionuclide (Beryllium-7) dating, and to determine sediment metal concentrations (As, Cu, Pb, and Zn) via ED-XRF measurements. Measured sediment Be-7 profiles indicate various sedimentation environments, where sediment accumulation, resuspension or redeposition is likely to occur. High metal concentrations were often corresponding to high Be-7 inventories in sediment cores. Possible sources of trace metal contaminants in the water column include: storm water run-off, Combined Sewer Overflows (CSOs), a well-documented industrial pollution event that occurred upstream in the early to mid twentieth century, and the resuspension of sediment. Existing and future data will provide baseline information for quantifying the effects of the proposed and pending environmental restoration project, which includes the removal of the Baker Dam. The combined pre- and post-Dam removal data may then be used in cost-benefit analyses for other similar estuarine restoration projects.

  9. Dry matter and nitrogen accumulation are not affected by superoptimal concentration of ammonium in flowing solution culture with pH control

    NASA Technical Reports Server (NTRS)

    Rideout, J. W.; Raper, C. D. Jr; Raper CD, J. r. (Principal Investigator)

    1994-01-01

    While it is known that superoptimal concentrations of the nitrate (NO3-) ion in solution culture do not increase NO3- uptake or dry matter accumulation, the same is not known for the ammonium (NH4+) ion. An experiment was conducted utilizing flowing solution culture with pH control to investigate the influence of superoptimal NH4+ concentrations on dry matter, nitrogen (N), potassium (K), calcium (Ca), and magnesium (Mg) accumulation by nonnodulated soybean plants. Increasing the NH4+ concentration in solution from 1 to 10 mM did not affect dry matter or N accumulation. Accumulations of K, Ca, and Mg were slightly decreased with increased NH4+ concentration. The NH4+ uptake system, which is saturated at less than 1mM NH4+, is able to regulate uptake of NH4+ at concentrations as high as 10 mM.

  10. High concentrations of isovaleric acid in the fats of odontocetes: variation and patterns of accumulation in blubber vs. stability in the melon.

    PubMed

    Koopman, H N; Iverson, S J; Read, A J

    2003-04-01

    Isovaleric acid (iso5:0) is an unusual fatty acid that is important for echolocation and hearing in acoustic tissues of some odontocetes, but its functional significance in blubber is unknown. We examined patterns of accumulation of this compound in blubber in 30 species of odontocetes ( n=299). Iso5:0 concentrations in blubber varied with phylogeny, ontogeny and body topography. Iso5:0 accumulated in greater quantities in superficial/outer blubber than in deep/inner blubber. In the outer blubber of northern right whale and Hector's dolphins, iso5:0 accounted for one-third to one-half of all fatty acids. Total blubber burden of iso5:0 in harbour porpoises represented up to 15 times the amount deposited in the melon. The composition of the melon does not change during starvation in harbour porpoises, supporting the hypothesis that lipids in melon are conserved for a specific function. Some odontocetes continually deposit iso5:0 in blubber after levels in melon have reached asymptotic levels, suggesting independent control of iso5:0 synthesis and storage in these compartments. Dolphins and porpoises inhabiting cold waters possess higher concentrations of iso5:0 in their outer blubber layers than species from warmer regions. We propose that this relationship represents an adaptive secondary role for iso5:0 in maintaining blubber flexibility in cold environments. PMID:12743728

  11. Water cycle dynamic increases resilience of vegetation under higher atmospheric carbon dioxide concentration

    NASA Astrophysics Data System (ADS)

    Lemordant, L. A.; Gentine, P.; Stéfanon, M.; Drobinski, P. J.; Fatichi, S.

    2015-12-01

    Plant stomata couple the energy, water and carbon cycles. Photosynthesis requires stomata to open to take up carbon dioxide. In the process water vapor is released as transpiration. As atmospheric CO2 concentration rises, for the same amount of CO2 uptake, less water vapor is transpired, translating into higher water use efficiency. Reduced water vapor losses will increase soil water storage if the leaf area coverage remains similar. This will in turn alter the surface energy partitioning: more heat will be dissipated as sensible heat flux, resulting in possibly higher surface temperatures. In contrast with this common hypothesis, our study shows that the water saved during the growing season by increased WUE can be mobilized by the vegetation and help reduce the maximum temperature of mid-latitude heat waves. The large scale meteorological conditions of 2003 are the basis of four regional model simulations coupling an atmospheric model to a surface model. We performed two simulations with respectively 2003 (CTL) and 2100 (FUT) atmospheric CO2 applied to both the atmospheric and surface models. A third (RAD) and a fourth (FER) simulations are run with 2100 CO2 concentration applied to respectively the atmospheric model only and the surface model only. RAD investigates the impact of the radiative forcing, and FER the response to vegetation CO2 fertilization. Our results show that the water saved through higher water use efficiency during the growing season enabled by higher atmospheric carbon dioxide concentrations helps the vegetation to cope during severe heat and dryness conditions in the summer of mid-latitude climate. These results demonstrate that consideration of the vegetation carbon cycle is essential to model the seasonal water cycle dynamic and land-atmosphere interactions, and enhance the accuracy of the model outputs especially for extreme events. They also have important implications for the future of agriculture, water resources management, ecosystems

  12. [Effects of elevated CO2 concentration and nitrogen deposition on the biomass accumulation and allocation in south subtropical main native tree species and their mixed communities].

    PubMed

    Zhao, Liang; Zhou, Guo-yi; Zhang, De-qiang; Duan, Hong-lang; Liu, Ju-xiu

    2011-08-01

    A 5-year experiment was conducted to study the effects of simulated elevated CO2 concentration, nitrogen deposition, and their combination on the biomass accumulation and allocation in five south subtropical native tree species Schima superba, Ormosia pinnata, Acmena acuminatissima, Syzygium hancei, and Castanopsis hystrix and their mixed communities. The test tree species had different responses in their biomass accumulation and allocation to the elevated CO2 concentration and nitrogen deposition. Elevated CO2 concentration and nitrogen deposition increased the biomass of legume species by 49.3% and 71.0%, respectively, and promoted the biomass accumulation in sun species. Nitrogen deposition increased the biomass of shade-preference species significantly, but elevated CO2 concentration was in adverse. Elevated CO2 concentration inhibited the biomass allocation in the belowground part of sun species but promoted the biomass allocation in the belowground part of shade-preference species. Elevated CO2 concentration, nitrogen deposition, and their interaction all promoted the biomass accumulation in mixed communities. Elevated CO2 concentration increased the biomass accumulation in the belowground part of the communities, while nitrogen deposition increased the biomass accumulation in the aboveground part. Under the background of global climate change, Ormosia pinnata and Castanopsis hystrix tended to be the appropriate species for carbon fixation in south subtropical area.

  13. Higher order concentration moments collapse in the expected mass fraction (EMF) based risk assessment

    NASA Astrophysics Data System (ADS)

    Srzic, Veljko; Gotovac, Hrvoje; Cvetkovic, Vladimir; Andricevic, Roko

    2014-05-01

    In this work Langrangian framework is used for conservative tracer transport simulations through 2-D extremely heterogeneous porous media. Conducted numerical simulations enable large sets of concentration values in both spatial and temporal domains. In addition to the advection, which acts on all scales, an additional mechanism considered is local scale dispersion (LSD), accounting for both mechanical dispersion and molecular diffusion. The ratio between these two mechanisms is quantified by the Peclet (Pe) number. In its base, the work gives answers to concentration scalar features when influenced by: i) different log-conductivity variance; ii) log-conductivity structures defined by the same global variogram but with different log conductivity patterns correlated; and iii) for a wide range of Peclet values. Results conducted by Monte Carlo analysis show a complex interplay between the aforementioned parameters, indicating the influence of aquifer properties to temporal LSD evolution. A remarkable collapse of higher order to second-order concentration moments [Yee, 2009] leads to the conclusion that only two concentration moments are required for an accurate description of concentration fluctuations. This explicitly holds for the pure advection case, while in the case of LSD presence the moment deriving function(MDF) is involved to ensure the moment collapse validity. An inspection of the Beta distribution leads to the conclusion that the two-parametric distribution can be used for concentration fluctuation characterization even in cases of high aquifer heterogeneity and/or for different log-conductivity structures, independent of the sampling volume used. Furthermore, the expected mass fraction (EMF) [Heagy & Sullivan, 1996] concept is applied in groundwater transport. In its origin, EMF is function of the concentration but with lower number of realizations needed for its determination, compared to the one point PDF. From practical point of view, EMF excludes

  14. Assessment of sources for higher Uranium concentration in ground waters of the Central Tamilnadu, India

    NASA Astrophysics Data System (ADS)

    Adithya, V. S.; Chidambaram, S.; Tirumalesh, K.; Thivya, C.; Thilagavathi, R.; Prasanna, M. V.

    2016-03-01

    The uranium concentration in groundwater has attained greater importance considering the health effects in mankind. Groundwater being the major source of uranium; sampling and analysis of groundwater for the major cations and anions along with uranium has been carried out in hard rock aquifers of Madurai district. The sampling has been carried out in varied aquifers like, Charnockites, Hornblende Biotite Gneiss, Granites, Quartzites, Laterites and sandstone. The cation and anions showed the following order of dominance Na+>Ca2+>Mg2+>K+ and that of anions are HCO3 ->Cl->SO4 2-> NO3 ->PO4 3-. Higher concentration of uranium was found along the granitic aquifers and it varied along the groundwater table condition. Further it was identified that the mineral weathering was the predominant source of U in groundwater. Tritium studies also reveal the fact that the younger waters are more enriched in uranium than the older groundwater with longer residence time.

  15. Cell wall targeted in planta iron accumulation enhances biomass conversion and seed iron concentration in Arabidopsis and rice.

    PubMed

    Yang, Haibing; Wei, Hui; Ma, Guojie; Antunes, Mauricio S; Vogt, Stefan; Cox, Joseph; Zhang, Xiao; Liu, Xiping; Bu, Lintao; Gleber, S Charlotte; Carpita, Nicholas C; Makowski, Lee; Himmel, Michael E; Tucker, Melvin P; McCann, Maureen C; Murphy, Angus S; Peer, Wendy A

    2016-10-01

    Conversion of nongrain biomass into liquid fuel is a sustainable approach to energy demands as global population increases. Previously, we showed that iron can act as a catalyst to enhance the degradation of lignocellulosic biomass for biofuel production. However, direct addition of iron catalysts to biomass pretreatment is diffusion-limited, would increase the cost and complexity of biorefinery unit operations and may have deleterious environmental impacts. Here, we show a new strategy for in planta accumulation of iron throughout the volume of the cell wall where iron acts as a catalyst in the deconstruction of lignocellulosic biomass. We engineered CBM-IBP fusion polypeptides composed of a carbohydrate-binding module family 11 (CBM11) and an iron-binding peptide (IBP) for secretion into Arabidopsis and rice cell walls. CBM-IBP transformed Arabidopsis and rice plants show significant increases in iron accumulation and biomass conversion compared to respective controls. Further, CBM-IBP rice shows a 35% increase in seed iron concentration and a 40% increase in seed yield in greenhouse experiments. CBM-IBP rice potentially could be used to address iron deficiency, the most common and widespread nutritional disorder according to the World Health Organization.

  16. The lead accumulation and hematological findings in juvenile rock fish Sebastes schlegelii exposed to the dietary lead (II) concentrations.

    PubMed

    Kim, Jun-Hwan; Kang, Ju-Chan

    2015-05-01

    Juvenile rockfish (mean length 14.2 ± 1.9 cm, and mean weight 57.3 ± 5.2g) were exposed for 4 weeks with the different levels of dietary lead (Pb(2+)) at 0, 30, 60, 120 and 240 mg/L. The exposure concentration and period of Pb have induced significant amount of it the specific tissues of rockfish. The highest Pb accumulation was observed in the kidney tissue by the dietary lead exposure. The growth rate and hepatosomatic index were considerably inhibited over 120 mg/kg. The hematological parameters such as red blood cell (RBC) counts, hematocrit (Ht) value, and hemoglobin (Hb) concentration were significantly decreased over 60 mg/kg Pb concentration. In the inorganic components, the values of calcium and magnesium in plasma were significantly decreased. The glucose and cholesterol values were notably increased, whereas total protein was decreased. The enzyme components, glutamic oxalate transaminase (GOT) and glutamic pyruvate transaminase (GPT), were significantly elevated by the dietary lead exposure, but no change was observed in alkaline phosphatase (ALP).

  17. Further studies on the use of enzyme profiles to monitor residue accumulation in wildlife: Plasma enzymes in starlings fed graded concentrations of morsodren, DDE, Aroclor 1254, and malathion

    USGS Publications Warehouse

    Dieter, M.P.

    1975-01-01

    Wild-trapped starlings (Sturnus vulgaris) were fed concentrations of Morsodren (2, 4, and 8 ppm), DDE or Aroclor 1254 (5, 25, and 100 ppm), or malathion (8, 35, and 160 ppm) that were found to be sublethal in pen-reared Coturnix quail fed these amounts for 12 weeks. Plasma enzymes had to be measured earlier than planned in starlings fed Morsodren (at three weeks) or the organochlorine compounds (at seven weeks) because of unexpected, subsequent mortality. Variations in enzyme response were greater in wild than in pen-reared birds, but not enough to mask the toxicant-induced changes in enzyme activity. Cholinesterase activities decreased in birds fed Morsodren or malathion, and increased in those fed the organochlorine compounds. Lactate dehydrogenase activities increased two-fold in starlings fed Morsodren and two- to four-fold in those fed the organochlorine compounds, but only 50% in those fed malathion. Further examination of enzyme profiles showed that creatine kinase and aspartate aminotransferase activities increased two-to four-fold in birds fed Morsodren or the organochlorine compounds but not at all in those fed malathion. Thus the classes of environmental contaminants fed to starlings could be easily distinguished by these enzymatic parameters. Evaluation of enzymatic profiles appears to be a potentially valuable technique to monitor the presence of toxicants in wild populations, especially if used to complement standard chemical residue analyses. Here the residue analyses showed, after three weeks feeding, that mercury in the carcasses reflected the concentrations fed daily, whereas accumulation in the livers was two- to four-fold greater. After seven weeks feeding, liver residues of either organochlorine compound were about three-fold higher than the concentrations fed daily. However, four times as much DDE as Aroclor 1254 had accumulated in the carcasses.

  18. Higher aluminum concentration in Alzheimer's disease after Box-Cox data transformation.

    PubMed

    Rusina, Robert; Matěj, Radoslav; Kašparová, Lucie; Kukal, Jaromír; Urban, Pavel

    2011-11-01

    Evidence regarding the role of mercury and aluminum in the pathogenesis of Alzheimer's disease (AD) remains controversial. The aims of our project were to investigate the content of the selected metals in brain tissue samples and the use of a specific mathematical transform to eliminate the disadvantage of a strong positive skew in the original data distribution. In this study, we used atomic absorption spectrophotometry to determine mercury and aluminum concentrations in the hippocampus and associative visual cortex of 29 neuropathologically confirmed AD and 27 age-matched controls. The Box-Cox data transformation was used for statistical evaluation. AD brains had higher mean aluminum concentrations in the hippocampus than controls (0.357 vs. 0.090 μg/g; P = 0.039) after data transformation. Results for mercury were not significant. Original data regarding microelement concentrations are heavily skewed and do not pass the normality test in general. A Box-Cox transformation can eliminate this disadvantage and allow parametric testing.

  19. Flurbiprofen concentration in soft tissues is higher after topical application than after oral administration

    PubMed Central

    Kai, Shuken; Kondo, Eiji; Kawaguchi, Yasuyuki; Kitamura, Nobuto; Yasuda, Kazunori

    2013-01-01

    Aim To compare tissue concentrations of flurbiprofen resulting from topical application and oral administration according to the regulatory approved dosing guidelines. Method Sixteen patients were included in this study. Each patient was randomly assigned to the topical application or oral administration group. In each group, a pair of tapes or a tablet, containing a total of 40 mg flurbiprofen, was administered twice at 16 and 2 h before the surgery. Results The flurbiprofen concentration in the fat, tendon, muscle and periosteum tissues was significantly higher (P < 0.0330) after topical application (992 ng g−1 [95% CI 482, 1503], 944 [95% CI 481, 1407], 492 [95% CI 248, 735], and 455 [95% CI 153, 756], respectively) than after oral administration (150 ng g−1 [95% CI 84, 217], 186 [95% CI 118, 254], 82 [95% CI 49, 116],and 221 [95% CI, 135, 307], respectively). Conclusion Topical application is an effective method to deliver flurbiprofen to the human body, particularly to soft tissues near the body surface. PMID:22822928

  20. Recent Increases in Snow Accumulation and Decreases in Sea-Ice Concentration Recorded in a Coastal NW Greenland Ice Core

    NASA Astrophysics Data System (ADS)

    Osterberg, E. C.; Thompson, J. T.; Wong, G. J.; Hawley, R. L.; Kelly, M. A.; Lutz, E.; Howley, J.; Ferris, D. G.

    2013-12-01

    A significant rise in summer temperatures over the past several decades has led to widespread retreat of the Greenland Ice Sheet (GIS) margin and surrounding sea ice. Recent observations from geodetic stations and GRACE show that ice mass loss progressed from South Greenland up to Northwest Greenland by 2005 (Khan et al., 2010). Observations from meteorological stations at the U.S. Thule Air Force Base, remote sensing platforms, and climate reanalyses indicate a 3.5C mean annual warming in the Thule region and a 44% decrease in summer (JJAS) sea-ice concentrations in Baffin Bay from 1980-2010. Mean annual precipitation near Thule increased by 12% over this interval, with the majority of the increase occurring in fall (SON). To improve projections of future ice loss and sea-level rise in a warming climate, we are currently developing multi-proxy records (lake sediment cores, ice cores, glacial geologic data, glaciological models) of Holocene climate variability and cryospheric response in NW Greenland, with a focus on past warm periods. As part of our efforts to develop a millennial-length ice core paleoclimate record from the Thule region, we collected and analyzed snow pit samples and short firn cores (up to 20 m) from the coastal region of the GIS (2Barrel site; 76.9317 N, 63.1467 W) and the summit of North Ice Cap (76.938 N, 67.671 W) in 2011 and 2012, respectively. The 2Barrel ice core was sampled using a continuous ice core melting system at Dartmouth, and subsequently analyzed for major anion and trace element concentrations and stable water isotope ratios. Here we show that the 2Barrel ice core spanning 1990-2010 records a 25% increase in mean annual snow accumulation, and is positively correlated (r = 0.52, p<0.01) with ERA-Interim precipitation. The 2Barrel annual sea-salt Na concentration is strongly correlated (r = 0.5-0.8, p<0.05) with summer and fall sea-ice concentrations in northern Baffin Bay near Thule (Figure 1). We hypothesize that the positive

  1. Accumulate-Repeat-Accumulate-Accumulate-Codes

    NASA Technical Reports Server (NTRS)

    Divsalar, Dariush; Dolinar, Sam; Thorpe, Jeremy

    2004-01-01

    Inspired by recently proposed Accumulate-Repeat-Accumulate (ARA) codes [15], in this paper we propose a channel coding scheme called Accumulate-Repeat-Accumulate-Accumulate (ARAA) codes. These codes can be seen as serial turbo-like codes or as a subclass of Low Density Parity Check (LDPC) codes, and they have a projected graph or protograph representation; this allows for a high-speed iterative decoder implementation using belief propagation. An ARAA code can be viewed as a precoded Repeat-and-Accumulate (RA) code with puncturing in concatenation with another accumulator, where simply an accumulator is chosen as the precoder; thus ARAA codes have a very fast encoder structure. Using density evolution on their associated protographs, we find examples of rate-lJ2 ARAA codes with maximum variable node degree 4 for which a minimum bit-SNR as low as 0.21 dB from the channel capacity limit can be achieved as the block size goes to infinity. Such a low threshold cannot be achieved by RA or Irregular RA (IRA) or unstructured irregular LDPC codes with the same constraint on the maximum variable node degree. Furthermore by puncturing the accumulators we can construct families of higher rate ARAA codes with thresholds that stay close to their respective channel capacity thresholds uniformly. Iterative decoding simulation results show comparable performance with the best-known LDPC codes but with very low error floor even at moderate block sizes.

  2. Accumulation of heavy metals in the fish, Oreochromis niloticus and Poecilia latipinna and their concentration in water and sediment of dam lake of Wadi Namar, Saudi Arabia.

    PubMed

    Ahmad, Zubair; Al-Ghanim, Khalid A; Al-Balawi, Hmoud F Al-Kahem; Al-Misned, Fahad; Maboob, Shahid; Suliman, El-Amin M

    2015-01-01

    The present study reports the accumulation of heavy metals like Cu, Hg, Cd, Pb and Cr in different tissues viz. liver, kidney, gills and muscles of Oreochromisniloticus and Poecilia latipinna from two sites in dam lake of Wadi Namar. Water and sediment samples were also collected from two sites for heavy metal analysis. Metal concentration in water and sediment samples of both the sites were observed in the following order: Cu>Cr>Pb>Cd>Hg; however, their concentration was found to be more at site 2 as compared to site 1. The order of metal accumulation in different tissues of O. niloticus and P. latipinna was in the following order: Cu>Cr>Pb>Cd>Hg at both the sites, while liver accumulated maximum amounts of metals followed by kidney, gills and muscles. The results showed the site 2 was more polluted by metals than Site 1 and O. niloticus accumulated greater amount of metals than P. latipinna.

  3. Influence of high concentrations of mineral salts on production process and NaCl accumulation by Salicornia europaea plants as a constituent of the LSS phototroph link.

    PubMed

    Tikhomirova, N A; Ushakova, S A; Kovaleva, N P; Gribovskaya, I V; Tikhomirov, A A

    2005-01-01

    biomass of an average plant totaled 8 g. The increase of K quantity in the experimental solutions resulted in an elevated content of the element in the plants. The increase of K uptake in the second experimental variant was accompanied by a 30-50% decrease of Na content in comparison with the other variants. Comparative Na content in the other variants was practically identical. N, Mg and P content in the control and experimental variants was also practically identical. The increase of S quantity in the second experimental variant also increased S uptake by the plants. But Ca quantity, accumulated in aboveground plants biomass in the experimental variants was lower than in the control. NaCl uptake by plants, depending on the concentration of mineral salts in the experimental solutions, ranged from 8 g (maximum salt content) up to 15 g (minimum salt content) on a plant growth area that totaled 0.032 m2. Thus, high concentrations of mineral salts simulating the content of mineral salts contained in urine did not result in a significant decrease of S. europaea productivity. The present work also considers the influence of higher light intensity concentrations on productivity and NaCl accumulation by S. europaea plants grown on experimental solutions with high salt content.

  4. Rice bran oil and oryzanol reduce plasma lipid and lipoprotein cholesterol concentrations and aortic cholesterol ester accumulation to a greater extent than ferulic acid in hypercholesterolemic hamsters.

    PubMed

    Wilson, Thomas A; Nicolosi, Robert J; Woolfrey, Benjamin; Kritchevsky, David

    2007-02-01

    plasma triglyceride concentrations compared to the control (-53% and -65%, respectively) and ferulic acid (-47% and -60%, respectively) diets. Hamsters fed the control and ferulic acid diets had significantly higher plasma vitamin E concentrations compared to the RBO (201% and 161%, respectively) and oryzanol (548% and 462%, respectively) diets; the ferulic acid and oryzanol diets had significantly lower plasma lipid hydroperoxide levels than the control (-57% and -46%, respectively) diet. The oryzanol-fed hamsters excreted significantly more coprostenol and cholesterol in their feces than the ferulic acid (127% and 120%, respectively) diet. The control diet had significantly greater aortic TC and FC accumulation compared to the RBO (115% and 89%, respectively), ferulic acid (48% and 58%, respectively) and the oryzanol (74% and 70%, respectively) diets. However, only the RBO and oryzanol diets had significantly lower aortic cholesterol ester accumulation compared to the control (-73% and -46%, respectively) diet. The present study suggests that at equal dietary levels, oryzanol has a greater effect on lowering plasma non-HDL-C levels and raising plasma HDL-C than ferulic acid, possibly through a greater extent to increase fecal excretion of cholesterol and its metabolites. However, ferulic acid may have a greater antioxidant capacity via its ability to maintain serum vitamin E levels compared to RBO and oryzanol. Thus, both oryzanol and ferulic acid may exert similar antiatherogenic properties, but through different mechanisms.

  5. Higher habitual intake of dietary fat and carbohydrates are associated with lower leptin and higher ghrelin concentrations in overweight and obese postmenopausal women with elevated insulin levels.

    PubMed

    Kong, Angela; Neuhouser, Marian L; Xiao, Liren; Ulrich, Cornelia M; McTiernan, Anne; Foster-Schubert, Karen E

    2009-11-01

    A highly regulated homeostatic system governs body weight; however, it is possible that this system might be impaired by the sustained intake of highly palatable foods. Short-term feeding studies suggest that the appetite-stimulating hormone ghrelin is suppressed less effectively by dietary fat intake, and diets high in sucrose decrease levels of the adipose hormone leptin. We hypothesized that higher habitual intake of dietary fat and carbohydrate (CHO) would be associated with elevated concentrations of circulating plasma ghrelin and lower circulating leptin in humans, a hormonal profile that could promote weight gain. To test our hypothesis, we examined the cross-sectional associations of ghrelin and leptin with the habitual macronutrient intake of 165 healthy overweight and obese sedentary women and tested the modifying role of insulin in these associations. We observed a significant inverse association between leptin concentrations and percentage energy from CHO independent of body mass index, percentage body fat, age, and intraabdominal fat (beta = -0.11 P = .04). No significant associations were observed between ghrelin and macronutrients or their subtypes among the total cohort. Among women with insulin concentrations at or greater than the median, we found a statistically significant positive association between intake of saturated fat and ghrelin concentrations, as well as additional statistically significant associations between leptin concentrations and macronutrients not observed among the total cohort. Our results provide some evidence that diets higher in fat and CHO are associated with a hormonal profile (ie, lower leptin and higher ghrelin concentrations), which could enhance weight gain, particularly among individuals with higher circulating insulin concentrations.

  6. A Lower Olfactory Capacity Is Related to Higher Circulating Concentrations of Endocannabinoid 2-Arachidonoylglycerol and Higher Body Mass Index in Women.

    PubMed

    Pastor, Antoni; Fernández-Aranda, Fernando; Fitó, Montserrat; Jiménez-Murcia, Susana; Botella, Cristina; Fernández-Real, Jose M; Frühbeck, Gema; Tinahones, Francisco J; Fagundo, Ana B; Rodriguez, Joan; Agüera, Zaida; Langohr, Klaus; Casanueva, Felipe F; de la Torre, Rafael

    2016-01-01

    The endocannabinoid (eCB) system can promote food intake by increasing odor detection in mice. The eCB system is over-active in human obesity. Our aim is to measure circulating eCB concentrations and olfactory capacity in a human sample that includes people with obesity and explore the possible interaction between olfaction, obesity and the eCB system. The study sample was made up of 161 females with five groups of body mass index sub-categories ranging from under-weight to morbidly obese. We assessed olfactory capacity with the "Sniffin´Sticks" test, which measures olfactory threshold-discrimination-identification (TDI) capacity. We measured plasma concentrations of the eCBs 2-arachidonoylglycerol (2-AG) and N-arachidonoylethanolamine or anandamide (AEA), and several eCB-related compounds, 2-acylglycerols and N-acylethanolamines. 2-AG and other 2-acylglycerols fasting plasma circulating plasma concentrations were higher in obese and morbidly obese subjects. AEA and other N-acylethanolamine circulating concentrations were lower in under-weight subjects. Olfactory TDI scores were lower in obese and morbidly obese subjects. Lower TDI scores were independently associated with higher 2-AG fasting plasma circulating concentrations, higher %body fat, and higher body mass index, after controlling for age, smoking, menstruation, and use of contraceptives. Our results show that obese subjects have a lower olfactory capacity than non-obese ones and that elevated fasting plasma circulating 2-AG concentrations in obesity are linked to a lower olfactory capacity. In agreement with previous studies we show that eCBs AEA and 2-AG, and their respective congeners have a distinct profile in relation to body mass index. The present report is the first study in humans in which olfactory capacity and circulating eCB concentrations have been measured in the same subjects. PMID:26849214

  7. A Lower Olfactory Capacity Is Related to Higher Circulating Concentrations of Endocannabinoid 2-Arachidonoylglycerol and Higher Body Mass Index in Women

    PubMed Central

    Pastor, Antoni; Fernández-Aranda, Fernando; Fitó, Montserrat; Jiménez-Murcia, Susana; Botella, Cristina; Fernández-Real, Jose M.; Frühbeck, Gema; Tinahones, Francisco J.; Fagundo, Ana B.; Rodriguez, Joan; Agüera, Zaida; Langohr, Klaus; Casanueva, Felipe F.; de la Torre, Rafael

    2016-01-01

    The endocannabinoid (eCB) system can promote food intake by increasing odor detection in mice. The eCB system is over-active in human obesity. Our aim is to measure circulating eCB concentrations and olfactory capacity in a human sample that includes people with obesity and explore the possible interaction between olfaction, obesity and the eCB system. The study sample was made up of 161 females with five groups of body mass index sub-categories ranging from under-weight to morbidly obese. We assessed olfactory capacity with the “Sniffin´Sticks” test, which measures olfactory threshold-discrimination-identification (TDI) capacity. We measured plasma concentrations of the eCBs 2-arachidonoylglycerol (2-AG) and N-arachidonoylethanolamine or anandamide (AEA), and several eCB-related compounds, 2-acylglycerols and N-acylethanolamines. 2-AG and other 2-acylglycerols fasting plasma circulating plasma concentrations were higher in obese and morbidly obese subjects. AEA and other N-acylethanolamine circulating concentrations were lower in under-weight subjects. Olfactory TDI scores were lower in obese and morbidly obese subjects. Lower TDI scores were independently associated with higher 2-AG fasting plasma circulating concentrations, higher %body fat, and higher body mass index, after controlling for age, smoking, menstruation, and use of contraceptives. Our results show that obese subjects have a lower olfactory capacity than non-obese ones and that elevated fasting plasma circulating 2-AG concentrations in obesity are linked to a lower olfactory capacity. In agreement with previous studies we show that eCBs AEA and 2-AG, and their respective congeners have a distinct profile in relation to body mass index. The present report is the first study in humans in which olfactory capacity and circulating eCB concentrations have been measured in the same subjects. PMID:26849214

  8. Energetics responses to higher greenhouse gas concentrations, and the role of the warming pattern

    NASA Astrophysics Data System (ADS)

    Hernandez-Deckers, D.; von Storch, J.

    2009-12-01

    Because of increasing greenhouse gas concentrations, the atmosphere warms up. However, it is not so evident whether this warming implies changes in the energetics of the atmosphere, i.e., the generation of available potential energy, its conversion into kinetic energy, and further dissipation. The Lorenz Energy Cycle (LEC) describes these processes, and provides a fundamental view of the atmosphere's behavior from which other properties may be inferred (like storm activity from the eddy components, for example). To study the energetics responses of the atmosphere, we diagnose changes in the LEC due to higher CO2 concentrations in the global atmosphere-ocean ECHAM5/MPI-OM model. We analyze two experiments in T63L31 resolution: 50 years from a preindustrial control experiment (1xCO2), and 50 years from a 2xCO2 equilibrium experiment (reached after 1% CO2-increase per year from the preindustrial run). The results are in good agreement with our previous results with a lower resolution version of the model (T31L19). Globally, doubling of CO2 results in a decrease in the LEC-strength --defined as the total conversion of available potential energy into kinetic energy-- but an increase in the zonal-mean kinetic energy (Km). These global changes are caused by the strengthening of the LEC in the upper troposphere and its weakening further below. The two opposite responses result from the simulated warming pattern that shows the strongest warming in the upper tropical troposphere and in the lower troposphere at high latitudes. This warming structure causes an increase in zonal mean available potential energy (Pm) in the upper troposphere and a net decrease further below, which triggers the two opposite responses. Regarding the response of the upper troposphere, the strong increase in Km can be reproduced using only the thermal wind relationship together with the simulated zonal mean warming pattern. A very good approximation is also achieved when considering the warming only

  9. Influence of high concentrations of mineral salts on production process and NaCl accumulation by Salicornia europaea plants as a constituent of the LSS phototroph link

    NASA Astrophysics Data System (ADS)

    Tikhomirova, N. A.; Ushakova, S. A.; Kovaleva, N. P.; Gribovskaya, I. V.; Tikhomirov, A. A.

    compounded 7,9g. In addition NaCl minimum content in above-ground plants organs in the experiment compounded 23 % and was equivalent to this parameter of the control variant. Thus, high concentrations of mineral salts contained in the human's fluid excretions after physicochemical processing cannot be the source of oppression of production processes and NaCl accumulations by S. europaea plants. In the given work the influence of higher light intensity and NaCl concentrations on productivity and NaCl accumulation by S.europaea plants grown on modeling solutions with high salt content is discussed.

  10. CONCENTRATION DEPENDENT ACCUMULATION OF [3H]-DELTAMETHRIN IN SODIUM CHANNEL N AV1.2 EXPRESSING XENOPUS LAEVIS OOCYTES.

    EPA Science Inventory

    Disruption of neuronal voltage-sensitive sodium channels (VSSCs) by pyrethroid insecticides such as deltamethrin (DLT) has been widely studied using Xenopus laevis oocytes transfected with VSSC. However, the extent of pyrethroid accumulation in VSSC-expressing oocytes is unknown....

  11. ESTIMATION OF BIOTA SEDIMENT ACCUMULATION FACTOR (BSAF) FROM PAIRED OBSERVATIONS OF CHEMICAL CONCENTRATIONS IN BIOTA AND SEDIMENT (FINAL REPORT)

    EPA Science Inventory

    Biota Sediment Accumulation Factor (BSAF) is a parameter describing bioaccumulation of sediment-associated organic compounds or metals into tissues of ecological receptors. The report provides information on methodologies to estimate BSAF for nonionic organic chemicals.

  12. Effect of inoculum concentrations of Aspergillus flavus and A. parasiticus on aflatoxin accumulation and kernel infection in resistant and susceptible maize hybrids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over a three year period, we compared aflatoxin accumulation and kernel infection in maize hybrids inoculated with six inoculum concentrations of Aspergillus flavus isolate NRRL 3357 or A. parasiticus isolate NRRL 6111 which is a norsolorinic acid producer. Aflatoxin resistant and susceptible mai...

  13. Clonal variation in heavy metal accumulation and biomass production in a poplar coppice culture: I. Seasonal variation in leaf, wood and bark concentrations.

    PubMed

    Laureysens, I; Blust, R; De Temmerman, L; Lemmens, C; Ceulemans, R

    2004-10-01

    The use of plants to decontaminate soils polluted by heavy metals has received considerable attention in recent years as a low-cost technique. Poplars (Populus spp.) can accumulate relatively high levels of certain metals, and have the added advantage of producing biomass that can be used for energy production. A short rotation coppice culture with 13 poplar clones was established on a former waste disposal site, which was moderately polluted with heavy metals. Total content of metals in leaves, wood and bark were determined in August and October/November. Significant clonal differences in accumulation were found for most metals, although clones with the highest concentration of all metals were not found. Cadmium, zinc and aluminium were most efficiently taken up. The lowest concentration was found in wood; the highest concentrations were generally found in senescing leaves, making removal and treatment of fallen leaves necessary.

  14. The influence of biotic and abiotic factors on (137)Cs accumulation in higher fungi after the accident at Chernobyl NPP.

    PubMed

    Zarubina, N

    2016-09-01

    Levels of soil contamination with (137)Cs, the belonging of fungi to a certain ecological group, the localization depth of the main part of mycelium in soil are the primary factors influencing the value of (137)Cs specific activity in higher fungi after the accident at Chernobyl NPP. It has been found that the value of (137)Cs specific activity in fungi of one species could vary by more than 10 times during a vegetation period. A correlation between the changes of (137)Cs content in fungi during the vegetation period and the amount of precipitates during various periods preceding the collection of samples has not been determined. An assumption has been proposed stating dependence between peculiarities of mycelium growth during the vegetation period and the changes of (137)Cs specific activity in fungi. PMID:26690320

  15. The influence of biotic and abiotic factors on (137)Cs accumulation in higher fungi after the accident at Chernobyl NPP.

    PubMed

    Zarubina, N

    2016-09-01

    Levels of soil contamination with (137)Cs, the belonging of fungi to a certain ecological group, the localization depth of the main part of mycelium in soil are the primary factors influencing the value of (137)Cs specific activity in higher fungi after the accident at Chernobyl NPP. It has been found that the value of (137)Cs specific activity in fungi of one species could vary by more than 10 times during a vegetation period. A correlation between the changes of (137)Cs content in fungi during the vegetation period and the amount of precipitates during various periods preceding the collection of samples has not been determined. An assumption has been proposed stating dependence between peculiarities of mycelium growth during the vegetation period and the changes of (137)Cs specific activity in fungi.

  16. Higher Fusarium Toxin Accumulation in Grain of Winter Triticale Lines Inoculated with Fusarium culmorum as Compared with Wheat †

    PubMed Central

    Góral, Tomasz; Wiśniewska, Halina; Ochodzki, Piotr; Walentyn-Góral, Dorota

    2016-01-01

    Resistance to Fusarium head blight in 32 winter triticale and 34 winter wheat accessions was evaluated. Triticale and wheat were sown in field experiments in two locations. At the time of flowering, heads were inoculated with three Fusarium culmorum isolates. Fusarium head blight index was scored and after the harvest percentage of Fusarium damaged kernels was assessed. Grain was analysed for type B trichothecenes (deoxynivalenol and derivatives, nivalenol) and zearalenone (ZEN) content. The average Fusarium head blight indexes were 28.0% for wheat and 19.2% for triticale accessions. The percentage of Fusarium damaged kernels was also higher for wheat and came to 55.6%, while for triticale this figure was 40.2%. The average content of deoxynivalenol (DON) for wheat amounted to 11.65 mg/kg and was lower than the result for triticale which was 14.12 mg/kg. The average contents of nivalenol were similar in both cereals: 4.13 mg/kg and 5.19 mg/kg for wheat and triticale respectively. Considerable amounts of DON derivatives in the cereals were also detected. The ZEN content in the grain was 0.60 mg/kg for wheat and 0.66 mg/kg for triticale. Relationships between Fusarium head blight index, Fusarium damaged kernels and mycotoxin contents were statistically significant for wheat and mostly insignificant for triticale. Triticale proved to have less infected heads and kernels than wheat. However, the content of type B trichothecenes was higher in triticale grain than in wheat grain. PMID:27763547

  17. Manganese accumulation in bone following chronic exposure in rats: steady-state concentration and half-life in bone.

    PubMed

    O'Neal, Stefanie L; Hong, Lan; Fu, Sherleen; Jiang, Wendy; Jones, Alexander; Nie, Linda H; Zheng, Wei

    2014-08-17

    Literature data indicate that bone is a major storage organ for manganese (Mn), accounting for 43% of total body Mn. However, the kinetic nature of Mn in bone, especially the half-life (t(1/2)), remained unknown. This study was designed to understand the time-dependence of Mn distribution in rat bone after chronic oral exposure. Adult male rats received 50 mg Mn/kg (as MnCl2) by oral gavage, 5 days per week, for up to 10 weeks. Animals were sacrificed every 2 weeks during Mn administration for the uptake study, and on day 1, week 2, 4, 8, or 12 after the cessation at 6-week Mn exposure for the t(1/2) study. Mn concentrations in bone (MnBn) were determined by AAS analysis. By the end of 6-week's treatment, MnBn appeared to reach the steady state (T(ss)) level, about 2-3.2 fold higher than MnBn at day 0. Kinetic calculation revealed t(1/2)s of Mn in femur, tibia, and humerus bone of 77 (r=0.978), 263 (r=0.988), and 429 (r=0.994) days, respectively; the average t(1/2) in rat skeleton was about 143 days, equivalent to 8.5 years in human bone. Moreover, MnBn were correlated with Mn levels in striatum, hippocampus, and CSF. These data support MnBn to be a useful biomarker of Mn exposure.

  18. Estimation of Biota Sediment Accumulation Factor (BSAF) from Paired Observations of Chemical Concentrations in Biota and Sediment (External Review Draft)

    EPA Science Inventory

    This report was written in response to a March 2004 request from EPA's Ecological Risk Assessment Forum (ERAF) for information about estimating Biota-Sediment Accumulation Factors (BSAFs). BSAF is a parameter describing bioaccumulation of sediment-associated organic compounds or...

  19. Thrombopoietin concentration in umbilical cord blood of healthy term newborns is higher than in adult controls.

    PubMed

    Walka, M M; Sonntag, J; Dudenhausen, J W; Obladen, M

    1999-01-01

    Thrombopoietin (TPO) concentrations were determined in umbilical cord plasma of 121 healthy term newborns. The lower detection limit of the enzyme immunoassay employed was 32.5 pg/ml. Median cord plasma TPO concentration was 78 (interquartile range 55-107) pg/ml. 95th percentile was 255 pg/ml. In only 8% (10/121), TPO was below the detection limit compared to 81% of healthy adults (25/31). In cord blood and adult controls, there were no significant correlations of TPO with platelet count or mass.

  20. The effect of carbon concentration and plastic deformation on ultrasonic higher order elastic properties of steel

    NASA Technical Reports Server (NTRS)

    Heyman, J. S.; Allison, S. G.; Salama, K.

    1985-01-01

    The behavior of higher order elastic properties, which are much more sensitive to material state than are second order properties, has been studied for steel alloys AISI 1016, 1045, 1095, and 8620 by measuring the stress derivative of the acoustic natural velocity to determine the stress acoustic constants (SAC's). Results of these tests show a 20 percent linear variation of SAC's with carbon content as well as even larger variations with prestrain (plastic deformation). The use of higher order elastic characterization permits quantitative evaluation of solids and may prove useful in studies of fatigue and fracture.

  1. Leaf Optical Properties in Higher Plants: Linking Spectral Characteristics to Stress and Chlorophyll Concentration

    NASA Technical Reports Server (NTRS)

    Carter, Gregory A.; Knapp, Alan K.

    2000-01-01

    A number of studies have linked responses in leaf spectral reflectance, transmittance or absorptance to physiological stress. A variety of stressors including dehydration, flooding,freezing, ozone, herbicides, competition, disease, insects and deficiencies in ectomycorrhizal development and N fertilization have been imposed on species ranging from grasses to conifers and deciduous trees. In this cases, the maximum difference in reflectance within the 400 - 850 nm wavelength range between control and stressed states occurred as a reflectance increase at wavelength near 700 nm. In studies that included transmittance and absorptance as well as reflectance, maximum differences occurred as increases and decreases, respectively, near 700 nm. This common optical response to stress could be simulated closely by varying the chlorophyll concentrations in senescent leaves of five species. The optical response to stress near 700 nm, as well as corresponding changes in reflectance that occur in the green-yellow spectrum, can be explained by the general tendency of stress to reduce leaf chlorophyll concentration.

  2. Higher Plasma S100B Concentrations in Schizophrenia Patients, and Dependently Associated with Inflammatory Markers

    PubMed Central

    Hong, Wu; Zhao, Min; Li, Haozhe; Peng, Fanglan; Wang, Fan; Li, Ningning; Xiang, Hui; Su, Yousong; Huang, Yueqi; Zhang, Shengyu; Zhao, Guoqin; Zhou, Rubai; Mao, Ling; Lin, Zhiguang; Fang, Yiru; Zhang, Qinting; Xie, Bin

    2016-01-01

    Glial damage and immune dysfunction are involved in pathogenesis of schizophrenia. However, interaction between glial damage and immune dysfunction in schizophrenia is undefined. This study aims to compare plasma S100 calcium binding protein (S100B) levels between schizophrenia patients and healthy participants, and to determine if immune markers are independently related with concentration of S100B in schizophrenia patients. Forty-one schizophrenia patients and thirty-three healthy volunteers were enrolled. Enzyme-linked immunosorbent assay (ELISA) was used to assess the concentrations of plasma S100B and inflammatory markers. We found that concentrations of S100B were elevated in schizophrenia patients than healthy participants (p < 0.05), and were negatively related with the severity of symptoms (p = 0.046). Receiver operating characteristic (ROC) curve analysis showed that different S100B levels between schizophrenia and healthy participants can be used as a clinical diagnostic factor (predictive value: 0.666, p = 0.015). Multiple linear regression analysis found that length of illness (Beta = −0.161), plasma levels of inflammatory regulation factors (including TGF-β1, logIL-23 and logIL-10) (Beta = 0.119, 0.475, 0.514) were independently associated with concentrations of S100B (Adjusted R2 = 0.897, p < 0.001). Therefore, our results suggest the possible function of S100B in pathogenesis of schizophrenia, and implicate the important role of autoimmune response and balance to glial dysfunction in patients with schizophrenia. PMID:27279465

  3. OPTIMIZATION OF SALT CONCENTRATIONS FOR A HIGHER CAROTENOID PRODUCTION IN DUNALIELLA SALINA (CHLOROPHYCEAE)(1).

    PubMed

    Farhat, Nèjia; Rabhi, Mokded; Falleh, Hanen; Jouini, Jihène; Abdelly, Chedly; Smaoui, Abderrazak

    2011-10-01

    Dunaliella salina (Dunal) Teodor, when treated over 25 d with a wide range of NaCl salinities (0.6-4.5 M), showed its maximal growth potentialities at 1.5-3.0 M NaCl and was able to survive even at 4.5 M NaCl. Sodium concentrations increased significantly at the supraoptimal salinities, reaching up to 5 mmol · g(-1) dry weight (dwt) at 4.5 M NaCl. Interestingly, ability of D. salina to take up essential mineral nutrients was not impaired by increased salinity. As for growth, chl concentrations were maximal in the 1.5-3.0 M NaCl range. Interestingly, carotenoid concentrations increased with the increasing salinity. The highest values of total antioxidant activity (5.2-6.9 mg gallic acid equivalents [GAE] · g(-1) dwt), antiradical activity, and reducing power were measured at 1.5-3.0 M NaCl. As a whole, these results showed that at 1.5-3.0 M NaCl, D. salina produce appreciable antioxidant level. But, once it reaches its growth maximum, a salt addition up to 4.5 M could enhance its carotenoid yield.

  4. Myotubes from Severely Obese Type 2 Diabetic Subjects Accumulate Less Lipids and Show Higher Lipolytic Rate than Myotubes from Severely Obese Non-Diabetic Subjects

    PubMed Central

    Bakke, Siril S.; Kase, Eili T.; Moro, Cedric; Stensrud, Camilla; Damlien, Lisbeth; Ludahl, Marianne O.; Sandbu, Rune; Solheim, Brita Marie; Rustan, Arild C.; Hjelmesæth, Jøran; Thoresen, G. Hege; Aas, Vigdis

    2015-01-01

    About 80% of patients with type 2 diabetes are classified as overweight. However, only about 1/3 of severely obese subjects have type 2 diabetes. This indicates that several severely obese individuals may possess certain characteristics that protect them against type 2 diabetes. We therefore hypothesized that this apparent paradox could be related to fundamental differences in skeletal muscle lipid handling. Energy metabolism and metabolic flexibility were examined in human myotubes derived from severely obese subjects without (BMI 44±7 kg/m2) and with type 2 diabetes (BMI 43±6 kg/m2). Lower insulin sensitivity was observed in myotubes from severely obese subjects with type 2 diabetes. Lipolysis rate was higher, and oleic acid accumulation, triacylglycerol content, and fatty acid adaptability were lower in myotubes from severely obese subjects with type 2 diabetes compared to severely obese non-diabetic subjects. There were no differences in lipid distribution and mRNA and protein expression of the lipases HSL and ATGL, the lipase cofactor CGI-58, or the lipid droplet proteins PLIN2 and PLIN3. Glucose and oleic acid oxidation were also similar in cells from the two groups. In conclusion, myotubes established from severely obese donors with established type 2 diabetes had lower ability for lipid accumulation and higher lipolysis rate than myotubes from severely obese donors without diabetes. This indicates that a difference in intramyocellular lipid turnover might be fundamental in evolving type 2 diabetes. PMID:25790476

  5. Cast Stone Formulation for Nuclear Waste Immobilization at Higher Sodium Concentrations

    DOE PAGES

    Fox, Kevin; Cozzi, Alex; Roberts, Kimberly; Edwards, Thomas

    2014-11-01

    Low activity radioactive waste at U.S. Department of Energy sites can be immobilized for permanent disposal using cementitious waste forms. This study evaluated waste forms produced with simulated wastes at concentrations up to twice that of currently operating processes. The simulated materials were evaluated for their fresh properties, which determine processability, and cured properties, which determine waste form performance. The results show potential for greatly reducing the volume of material. Fresh properties were sufficient to allow for processing via current practices. Cured properties such as compressive strength meet disposal requirements. Leachability indices provide an indication of expected long-term performance.

  6. Higher Potassium Concentration in Shoots Reduces Gray Mold in Sweet Basil.

    PubMed

    Yermiyahu, Uri; Israeli, Lior; David, Dalia Rav; Faingold, Inna; Elad, Yigal

    2015-08-01

    Nutritional elements can affect plant susceptibility to plant pathogens, including Botrytis cinerea. We tested the effect of potassium (K) fertilization on gray mold in sweet basil grown in pots, containers, and soil. Increased K in the irrigation water and in the sweet basil tissue resulted in an exponential decrease in gray mold severity. Potassium supplied to plants by foliar application resulted in a significant decrease in gray mold in plants grown with a low rate of K fertigation. Lower K fertigation resulted in a significant increase in B. cinerea infection under semi-commercial conditions. Gray mold severity in harvested shoots was significantly negatively correlated with K concentration in the irrigation solution, revealing resistance to B. cinerea infection as a result of high K concentration in sweet basil tissue. Gray mold was reduced following K foliar application of the plants. In general, there was no synergy between the fertigation and foliar spray treatments. Proper K fertilization can replace some of the required chemical fungicide treatments and it may be integrated into gray mold management for improved disease suppression. PMID:25760521

  7. Higher Potassium Concentration in Shoots Reduces Gray Mold in Sweet Basil.

    PubMed

    Yermiyahu, Uri; Israeli, Lior; David, Dalia Rav; Faingold, Inna; Elad, Yigal

    2015-08-01

    Nutritional elements can affect plant susceptibility to plant pathogens, including Botrytis cinerea. We tested the effect of potassium (K) fertilization on gray mold in sweet basil grown in pots, containers, and soil. Increased K in the irrigation water and in the sweet basil tissue resulted in an exponential decrease in gray mold severity. Potassium supplied to plants by foliar application resulted in a significant decrease in gray mold in plants grown with a low rate of K fertigation. Lower K fertigation resulted in a significant increase in B. cinerea infection under semi-commercial conditions. Gray mold severity in harvested shoots was significantly negatively correlated with K concentration in the irrigation solution, revealing resistance to B. cinerea infection as a result of high K concentration in sweet basil tissue. Gray mold was reduced following K foliar application of the plants. In general, there was no synergy between the fertigation and foliar spray treatments. Proper K fertilization can replace some of the required chemical fungicide treatments and it may be integrated into gray mold management for improved disease suppression.

  8. Higher Plasma Concentration of Food-Specific Antibodies in Persons with Autistic Disorder in Comparison to Their Siblings

    ERIC Educational Resources Information Center

    Trajkovski, Vladimir; Petlichkovski, Aleksandar; Efinska-Mladenovska, Olivija; Trajkov, Dejan; Arsov, Todor; Strezova, Ana; Ajdinski, Ljubomir; Spiroski, Mirko

    2008-01-01

    Specific IgA, IgG, and IgE antibodies to food antigens in 35 participants with autistic disorder and 21 of their siblings in the Republic of Macedonia were examined. Statistically significant higher plasma concentration of IgA antibodies against alpha-lactalbumin, beta-lactoglobulin, casein, and gliadin were found in the children with autistic…

  9. Investigation of Higher Than Standard Lead Concentrations in Drinking Water From Washington, D.C.

    NASA Astrophysics Data System (ADS)

    Adarkwah, N. E.; Ararso, I.; Garcia, N.; Goldman, A.; Lieu, C.; Mondragon, J.; Swamy, V.; Unigarro, M.; Cuff, K.

    2005-12-01

    For over two years, the Washington, D.C. area has been plagued by the incidence of alarming concentrations of lead found in local drinking water. During this period, water with lead concentration levels above the U.S. Environmental Protection Agency's (EPA) action limit of 15 ppb has been found in approximately 66% of the homes tested. Because of the problems with lead in drinking water in the D.C. area, the EPA has begun the process of trying to determine whether or not this problem occurs nationwide by obtaining as much lead data as possible. However, it recently reported that no current information exists on lead levels from 78 percent of the nation's public drinking water systems, and that it has no data from as many as 20 states. In an effort to generate information that contributes to a greater understanding of the scope and nature of this real-world environmental health problem, we have begun collecting and performing lead analysis of drinking water samples from different parts of the country. As San Francisco Bay Area - based participants in the NSF-sponsored Environmental Science Information Technology Activities (ESITA) project, we began by establishing E-mail correspondence with children who attend elementary schools in the Washington, D.C. area two years ago, during the first year of the lead crisis. Since that time the elementary school children have sent over 150 water samples from their homes and schools, along with information on the locations from which the water samples were collected to the Bay Area. Upon receipt, we prepare and analyze these samples at UC Berkeley's Lawrence Hall of Science. Following analysis results are compiled, statistically analyzed, and used to create maps that aid in the interpretation of our data. The majority of samples collected from the D.C. area were obtained from schools and homes located in the central north-northeast section of the District. Of these samples, 72% contained lead in excess of the EPA action limit

  10. Monitoring of PBDEs concentration in umbilical cord blood and breast milk from Korean population and estimating the effects of various parameters on accumulation in humans.

    PubMed

    Kim, Un-Jung; Lee, In-Seok; Kim, Hyung Sik; Oh, Jeong-Eun

    2011-10-01

    In this study, we investigated concentration, congener distribution pattern, and effects of potential environmental factors that affect PBDE accumulation. We also estimated correlation between PBDE concentration and health status or thyroid function by analyzing 90 cord blood and 21 breast milk samples obtained from Korean population. Seven from tri- to hepta-BDEs were analyzed by solid phase extraction-high-resolution gas chromatography/high-resolution mass spectrometry (SPE-HRGC/HRMS). The total concentration of 7 PBDEs in cord blood was 2.786-94.64 ng g(-1) lipid and that in breast milk was 1.076-8.664 ng g(-1) lipid. Tetra-BDE (#47) was the predominant type of PBDE and was present at concentrations of over 40% in both sample types. A weak correlation was observed between the concentration of BDE28 and 153 and thyroid hormone concentration only in the breast milk samples. In children, a weak negative correlation was observed between free thyroxine (FT4) concentration and BDE28 concentration (0.302, p<0.05), while in mothers, a weak positive correlation was observed between thyroid hormone concentration and BDE153 concentration (0.403, p<0.05). No significant correlations between PBDE concentration and work and residential environments were found in this study, but a weak correlation between BDE concentration in cord blood and potential PBDE sources was confirmed by investigating the frequency of oil paint usage (0.510, p<0.001). A weak correlation was also found between PBDE concentration in breast milk during pregnancy and dietary habits such as green tea drinking (0.541, p=0.025) and Trichiuridae intake (0.565, p=0.015). PMID:21890170

  11. The evaluation of heavy metal accumulation and application of a comprehensive bio-concentration index for woody species on contaminated sites in Hunan, China.

    PubMed

    Zhao, Xiulian; Liu, Jianfeng; Xia, Xinli; Chu, Jianmin; Wei, Yuan; Shi, Shengqing; Chang, Ermei; Yin, Weilun; Jiang, Zeping

    2014-04-01

    Fast-growing metal-accumulating woody plants are considered potential candidates for phytoextraction of metals. Shuikoushan mining, one of the biggest Pb and Zn production bases in China, presents an important source of the pollution of environment during the last 100 years. Over 150 km(2) of fertile soil have been contaminated by the dust, slag, and tailings from this mining. The goal of the present work has been to determine the content of Pb, Zn, Cd, and Cu in wild woody plants (18 species) naturally growing in this area. Two hundred five plant and soil samples from 11 contaminated sites were collected and analyzed. In addition, to assess the ability of multi-metal accumulation of these trees, we proposed a predictive comprehensive bio-concentration index (CBCI) based on fuzzy synthetic assessment. Our data suggest some adult trees could also accumulate a large amount of metals. Pb concentrations in leaves of Paulownia fortunei (Seem.) Hemsl. (1,179 mg/kg) exceeded the hyperaccumulation threshold (1,000 mg/kg). Elevated Pb concentrations (973.38 mg/kg) were also found in the leaves of Broussonetia papyrifera (L.) Vent., with a Pb bio-concentration factor of up to 0.701. Endemic species, Zenia insignis Chun exhibited huge potential for Zn and Cd phytoextraction, with the highest concentrations of Zn (1,968 mg/kg) and Cd (44.40 mg/kg), characteristic root nodules, and fast growth rates in poor soils. As for multi-metal accumulation ability, native species B. papyrifera was calculated to have the most exceptional ability to accumulate various metals simultaneously (CBCI 2.93), followed by Amorpha fruticosa L. (CBCI 2.72) and Lagerstroemia indica L. (CBCI 2.53). A trend of increasing metal from trunks to leaves (trunks < branches < leaves) and towards fine roots has been shown by metal partitioning between tissues. The proposed CBCI would allow for the selection of suitable trees for phytoremediation in the future. PMID:24374615

  12. Astrocytic and neuronal accumulation of elevated extracellular K+ with a 2/3 K+/Na+ flux ratio—consequences for energy metabolism, osmolarity and higher brain function

    PubMed Central

    Hertz, Leif; Xu, Junnan; Song, Dan; Yan, Enzhi; Gu, Li; Peng, Liang

    2013-01-01

    Brain excitation increases neuronal Na+ concentration by 2 major mechanisms: (i) Na+ influx caused by glutamatergic synaptic activity; and (ii) action-potential-mediated depolarization by Na+ influx followed by repolarizating K+ efflux, increasing extracellular K+ concentration. This review deals mainly with the latter and it concludes that clearance of extracellular K+ is initially mainly effectuated by Na+,K+-ATPase-mediated K+ uptake into astrocytes, at K+ concentrations above ~10 mM aided by uptake of Na+,K+ and 2 Cl− by the cotransporter NKCC1. Since operation of the astrocytic Na+,K+-ATPase requires K+-dependent glycogenolysis for stimulation of the intracellular ATPase site, it ceases after normalization of extracellular K+ concentration. This allows K+ release via the inward rectifying K+ channel Kir4.1, perhaps after trans-astrocytic connexin- and/or pannexin-mediated K+ transfer, which would be a key candidate for determination by synchronization-based computational analysis and may have signaling effects. Spatially dispersed K+ release would have little effect on extracellular K+ concentration and allow K+ accumulation by the less powerful neuronal Na+,K+-ATPase, which is not stimulated by increases in extracellular K+. Since the Na+,K+-ATPase exchanges 3 Na+ with 2 K+, it creates extracellular hypertonicity and cell shrinkage. Hypertonicity stimulates NKCC1, which, aided by β-adrenergic stimulation of the Na+,K+-ATPase, causes regulatory volume increase, furosemide-inhibited undershoot in [K+]e and perhaps facilitation of the termination of slow neuronal hyperpolarization (sAHP), with behavioral consequences. The ion transport processes involved minimize ionic disequilibria caused by the asymmetric Na+,K+-ATPase fluxes. PMID:23986689

  13. Carvacrol and rosemary oil at higher concentrations induce apoptosis in human hepatoma HepG2 cells.

    PubMed

    Melušová, Martina; Jantová, Soňa; Horváthová, Eva

    2014-12-01

    Natural essential oils are volatile herbal complex compounds which manifest cytotoxic effects on living cells depending on their type and concentration but usually they are not genotoxic. Our previous studies showed that carvacrol (CA) and rosemary essential oil (RO) induced growth inhibition of both human cell lines HepG2 and BHNF-1, with hepatoma HepG2 cells being more sensitive to either compound tested. Cytotoxic concentrations of CA and RO induced the formation of DNA strand breaks. Further ex vivo studies showed that extracts prepared from hepatocytes of CA- and RO-supplemented rats did not increase incision repair activity compared to extracts from liver cells of control animals. Therefore, the aim of this work was to determine the effect of cytotoxic concentrations of CA and RO on the cell cycle and the ability of both natural volatiles to induce DNA fragmentation and apoptotic death of human hepatoma HepG2 cells. These effects were measured after 24 h incubation of HepG2 cells with CA and RO using three independent methods - flow cytometry, internucleosomal DNA fragmentation (electrophoresis) and micronucleus assay. Evaluation of morphological changes and formation of micronuclei in HepG2 cells showed no increase in the number of micronuclei in cells treated by CA and RO compared to control cells. On the other hand, CA and RO induced morphological changes typical for apoptosis in concentration-dependent manner. The presence of necrosis was negligible. Both natural compounds caused shrinking of cytoplasmic membrane and formation of apoptotic bodies. In addition, the highest concentrations of CA and RO induced internucleosomal DNA fragmentation (formation of DNA ladder) in HepG2 cells. Cell cycle analysis revealed the accumulation of cells in the G1 phase, which was accompanied by a reduction in the number of cells in the S phase after 24 h exposure to the substances tested. The cell division was thus slowed down or stopped and this process resulted in cell

  14. Combined effects of elevated temperature and CO2 concentration on Cd and Zn accumulation dynamics in Triticum aestivum L.

    PubMed

    Wang, Xiaoheng; Li, Yu; Lu, Hong; Wang, Shigong

    2016-09-01

    A simulated climate warming experiment was conducted to evaluate the combined effects of elevated temperature and CO2 concentration on the bioaccumulation, translocation and subcellular distributions of Cd and Zn in wheat seedlings (Triticum aestivum L. cv. Xihan 1.) at Dingxi, Gansu Province, China. The objective was to find evidence that global climate change is affecting the bioaccumulation of Cd and Zn in T. aestivum L. cv. Xihan 1. The results showed that compared to control A, elevated temperature and CO2 increased Cd bioaccumulation in the shoots by 1.4-2.5 times, and increased that in the roots by 1.2-1.5 times, but decreased Zn levels in wheat shoots by 1.4-2.0 times, while decreased that in the roots by 1.6-1.9 times. Moreover, temperature and CO2 concentration increase also led to increased Cd concentration, and decreased Zn concentration in subcellular compartments of wheat seedlings. The largest Cd concentration increase (174.4%) was observed in the cell wall and debris fractions of shoots after they were subjected to the highest CO2 and temperature treatment (TC3). The largest Zn concentration decrease (53.1%) was observed in the soluble (F3) fractions of shoots after they were subjected to the medium CO2 and temperature treatment (TC2). The temperature and CO2 increase had no significant effect on the proportional distribution of Cd and Zn in the subcellular fractions. The root-to-shoot translocation of Cd increased with the increasing temperature and CO2 concentration. However, the Zn distributions only fluctuated within a small range.

  15. Combined effects of elevated temperature and CO2 concentration on Cd and Zn accumulation dynamics in Triticum aestivum L.

    PubMed

    Wang, Xiaoheng; Li, Yu; Lu, Hong; Wang, Shigong

    2016-09-01

    A simulated climate warming experiment was conducted to evaluate the combined effects of elevated temperature and CO2 concentration on the bioaccumulation, translocation and subcellular distributions of Cd and Zn in wheat seedlings (Triticum aestivum L. cv. Xihan 1.) at Dingxi, Gansu Province, China. The objective was to find evidence that global climate change is affecting the bioaccumulation of Cd and Zn in T. aestivum L. cv. Xihan 1. The results showed that compared to control A, elevated temperature and CO2 increased Cd bioaccumulation in the shoots by 1.4-2.5 times, and increased that in the roots by 1.2-1.5 times, but decreased Zn levels in wheat shoots by 1.4-2.0 times, while decreased that in the roots by 1.6-1.9 times. Moreover, temperature and CO2 concentration increase also led to increased Cd concentration, and decreased Zn concentration in subcellular compartments of wheat seedlings. The largest Cd concentration increase (174.4%) was observed in the cell wall and debris fractions of shoots after they were subjected to the highest CO2 and temperature treatment (TC3). The largest Zn concentration decrease (53.1%) was observed in the soluble (F3) fractions of shoots after they were subjected to the medium CO2 and temperature treatment (TC2). The temperature and CO2 increase had no significant effect on the proportional distribution of Cd and Zn in the subcellular fractions. The root-to-shoot translocation of Cd increased with the increasing temperature and CO2 concentration. However, the Zn distributions only fluctuated within a small range. PMID:27593278

  16. Obese Women Have Lower Monosodium Glutamate Taste Sensitivity and Prefer Higher Concentrations Than Do Normal-weight Women

    PubMed Central

    Pepino, M. Yanina; Finkbeiner, Susana; Beauchamp, Gary K.; Mennella, Julie A.

    2010-01-01

    The goal of this study was to determine whether obese women exhibit altered umami and sweet taste perception compared to normal-weight women. A total of 57 subjects (23 obese and 34 normal weight) participated in a 2-day study separated by 1 week. Half of the women in each group were evaluated using monosodium glutamate (MSG; prototypical umami stimulus) on the first test day and sucrose on the second test day; the order was reversed for the remaining women. We used two-alternative forced-choice staircase procedures to measure taste detection thresholds, forced-choice tracking technique to measure preferences, the general Labeled Magnitude Scale (gLMS) to measure perceived intensity of suprathreshold concentrations, and a triangle test to measure discrimination between 29 mmol/l MSG and 29 mmol/l NaCl. Obese women required higher MSG concentrations to detect a taste and preferred significantly higher MSG concentrations in a soup-like vehicle. However, their perception of MSG at suprathreshold concentrations, their ability to discriminate MSG from salt, and their preference for sucrose were similar to that observed in normal-weight women. Regardless of their body weight category, 28% of the women did not discriminate 29 mmol/l MSG from 29 mmol/l NaCl (nondiscriminators). Surprisingly, we found that, relative to discriminators, nondiscriminators perceived less savoriness when tasting suprathreshold MSG concentrations and less sweetness from suprathreshold sucrose concentrations but had similar MSG and sucrose detection thresholds. Taken together, these data suggest that body weight is related to some components of umami taste and that different mechanisms are involved in the perception of threshold and suprathreshold MSG concentrations. PMID:20075854

  17. Arsenic response of AtPCS1- and CePCS-expressing plants - effects of external As(V) concentration on As-accumulation pattern and NPT metabolism.

    PubMed

    Wojas, Sylwia; Clemens, Stephan; Skłodowska, Aleksandra; Maria Antosiewicz, Danuta

    2010-02-15

    Phytochelatins (PCs) are small, cysteine-rich peptides, known to play a major role in detoxification of both cadmium and arsenic. The aim of this study was to determine whether overexpression of either of two PC synthase (PCS) genes, AtPCS1 and CePCS in Nicotiana tabacum (previously shown to cause decrease and increase, respectively, of cadmium tolerance of tobacco - Wojas et al., 2008) also contributes to such contrasting phenotypes with respect to arsenic (As) tolerance and accumulation, and how observed responses relate to non-protein thiol (NPT) metabolism. The expression of both genes resulted in an increase of As-tolerance, with CePCS plants most tolerant. We showed for the first time that the response of PCS overexpressing plants to As qualitatively depends on the external As(V) concentration. At the less toxic 50muM As(V), AtPCS1 and CePCS transformants accumulated more As in roots and leaves than WT. An increase in PC production and the level of PC2 species was detected in leaves of AtPCS1 and CePCS plants, which might explain their enhanced As-accumulation and tolerance. In contrast, at the highly toxic 200muM As(V), several disturbances in thiol metabolism of PCS overexpressing plants were found, surprisingly, including decrease of PC levels both in roots and leaves of transgenic plants relative to WT. The increase in As-tolerance and accumulation due to AtPCS1 and CePCS overexpression, observed at the As(V) concentrations similar to those found in As-contaminated soils, makes these genes promising candidates for plant engineering for phytoremediation.

  18. Dietary source of stearidonic acid promotes higher muscle DHA concentrations than linolenic acid in hybrid striped bass.

    PubMed

    Bharadwaj, Anant S; Hart, Steven D; Brown, Billie J; Li, Yong; Watkins, Bruce A; Brown, Paul B

    2010-01-01

    Rapid expansion of aquacultural production is placing increasing demand on fish oil supplies and intensified the search for alternative lipid sources. Many of the potential alternative sources contain low concentrations of long chain n-3 fatty acids and the conversion of dietary linolenic acid to longer chain highly unsaturated fatty acids is a relatively inefficient process in some species. A 6-week study was conducted to compare tissue fatty acid (FA) concentrations in hybrid striped bass fed either 18:3n-3 (alpha-linolenic acid; ALA) or 18:4n-3 (stearidonic acid; SDA). Hybrid striped bass were fed either a control diet containing fish oil, or diets containing ALA or SDA at three different levels (0.5, 1 and 2% of the diet). There were no significant differences in whole animal responses between fish fed ALA or SDA. Liver and muscle concentrations of ALA and SDA were responsive to dosages fed. However, only 22:6n-3 concentrations in muscle were significantly affected by dietary source of 18 carbon precursors. Muscle 22:6n-3 concentrations were significantly higher in fish fed SDA compared to fish fed ALA. Based on these data, it appears that feeding SDA can increase long chain n-3 fatty acid concentrations in fish muscle.

  19. Higher serum total bilirubin concentration is associated with lower risk of renal insufficiency in an adult population

    PubMed Central

    Lee, Ang-Tse; Wang, Ya-Yu; Lin, Shih-Yi; Liang, Jiin-Tsae; Sheu, Wayne Huey-Herng; Song, Yuh-Min; Chang, Wen-Dau

    2015-01-01

    Background: Chronic inflammation is proposed to play a central role in the pathogenesis of chronic kidney disease (CKD), and serum bilirubin has antioxidant and anti-inflammatory effects. We investigated the association between serum total bilirubin (Tb) concentration and renal function in an adult population. Methods: We conducted a cross-sectional study and collected anthropometric measurements, fasting blood tests, lifestyle habits and medical history of 3876 subjects attending a health examination. Renal insufficiency was defined as estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2 calculated by using the CKD-EPI equation. Results: Serum Tb concentrations were higher in subjects without renal insufficiency than in those with renal insufficiency. Multivariable linear regression analysis showed that Tb concentration was positively associated with eGFR after adjusting for important CKD risk factors (P=0.04). Multivariable logistic regression analysis also revealed that higher Tb concentration (each increment of 1.71 μmol/L) (0.1 mg/dL) was associated with a reduced risk of renal insufficiency: odds ratios were 0.94 (P=0.005) for men and 0.90 (P=0.015) for women, respectively. When subjects were divided into quartiles of serum Tb, multivariable-adjusted odds ratios for renal insufficiency comparing the fourth to the first Tb quartile were 0.49 (P=0.001) for men and 0.35 (P=0.003) for women. A stepwise exclusion of subjects, first those with possible liver disease and second, those with CKD stage 4 and 5, showed consistent results. Conclusion: Higher serum Tb concentration was associated with lower risk of renal insufficiency, regardless of other conventional CKD risk factors. PMID:26770557

  20. Responses in growth, lipid accumulation, and fatty acid composition of four oleaginous microalgae to different nitrogen sources and concentrations

    NASA Astrophysics Data System (ADS)

    Li, Tao; Wan, Linglin; Li, Aifen; Zhang, Chengwu

    2013-11-01

    Nitrogen deficiency is an effective strategy for enhancing lipid production in microalgae. Close relationships exist among lipid production, microalgal species, and nitrogen sources. We report growth, lipid accumulation, and fatty acid composition in four microalgae ( Chlorococcum ellipsoideum UTEX972, Chlorococcum nivale LB2225, Chlorococcum tatrense UTEX2227, and Scenedesmus deserticola JNU19) under nitrate- and urea-nitrogen deficiencies. We found three patterns of response to nitrogen deficiency: Type-A (decrease in biomass and increase in lipid content), Type-B (reduction in both biomass and lipid content), and Type-C (enhancement of both biomass and lipid content). Type-C microalgae are potential candidates for large-scale oil production. Chlorococcum ellipsoideum, for example, exhibited a neutral lipid production of up to 239.6 mg/(L·d) under urea-nitrogen deficiency. In addition, nitrogen deficiency showed only a slight influence on lipid fractions and fatty acid composition. Our study provides useful information for further screening hyper-lipid microalgal strains for biofuel production.

  1. Vertical distribution of trace-element concentrations and occurrence of metallurgical slag particles in accumulated bed sediments of Lake Roosevelt, Washington, September 2002

    USGS Publications Warehouse

    Cox, S.E.; Bell, P.R.; Lowther, J.S.; Van Metre, P.C.

    2005-01-01

    Sediment cores were collected from six locations in Lake Roosevelt to determine the vertical distributions of trace-element concentrations in the accumulated sediments of Lake Roosevelt. Elevated concentrations of arsenic, cadmium, copper, lead, mercury, and zinc occurred throughout much of the accumulated sediments. Concentrations varied greatly within the sediment core profiles, often covering a range of 5 to 10 fold. Trace-element concentrations typically were largest below the surficial sediments in the lower one-half of each profile, with generally decreasing concentrations from the 1964 horizon to the surface of the core. The trace-element profiles reflect changes in historical discharges of trace elements to the Columbia River by an upstream smelter. All samples analyzed exceeded clean-up guidelines adopted by the Confederated Tribes of the Colville Reservation for cadmium, lead, and zinc and more than 70 percent of the samples exceeded cleanup guidelines for mercury, arsenic, and copper. Although 100 percent of the samples exceeded sediment guidelines for cadmium, lead, and zinc, surficial concentrations of arsenic, copper, and mercury in some cores were less than the sediment-quality guidelines. With the exception of copper, the trace-element profiles of the five cores collected along the pre-reservoir Columbia River channel typically showed trends of decreasing concentrations in sediments deposited after the 1964 time horizon. The decreasing concentrations of trace elements in the upper half of cores from along the pre-reservoir Columbia River showed a pattern of decreasing concentrations similar to reductions in trace-element loading in liquid effluent from an upstream smelter. Except for arsenic, trace-element concentrations typically were smaller at downstream reservoir locations along the pre-reservoir Columbia River. Trace-element concentration in sediments from the Spokane Arm of the reservoir showed distinct differences compared to the similarities

  2. Effects of inorganic carbon concentration on carbon formation, nitrate utilization, biomass and oil accumulation of Nannochloropsis oculata CS 179.

    PubMed

    Lin, Qiang; Gu, Na; Li, Gang; Lin, Junda; Huang, Liangmin; Tan, LingLing

    2012-05-01

    This investigation examined the effects of the inorganic carbon concentration (4, 0.8 and 0 g/L NaHCO(3)) on the carbon formation, nitrate utilization, growth and fatty acids compositions of Nannochloropsis oculata. The dissolved inorganic carbon (DIC) concentration in the three treatments decreased sharply during the first 6 days, and the percentage of dissolved organic carbon (DOC) (% of total organic carbon (TOC)) decreased with the depletion of the DIC. The NO(3)(-) assimilation of the algae was correlated with the DIC concentration. The algae in the highest DIC treatment had the highest specific grow rate (0.0843 d(-1)) (P<0.0001), and their biomass and fatty acid methyl esters (FAME) productivity were 84.00 and 9.69 mg/L/d, respectively (P<0.0001). Contents of C16 and C18 series (% of FAME) were high and the C16:0 increased with the decrease of C18:1 during the cultivation. The iodine value (IV) of the algae was low at the low DIC media. PMID:22386465

  3. Effects of inorganic carbon concentration on carbon formation, nitrate utilization, biomass and oil accumulation of Nannochloropsis oculata CS 179.

    PubMed

    Lin, Qiang; Gu, Na; Li, Gang; Lin, Junda; Huang, Liangmin; Tan, LingLing

    2012-05-01

    This investigation examined the effects of the inorganic carbon concentration (4, 0.8 and 0 g/L NaHCO(3)) on the carbon formation, nitrate utilization, growth and fatty acids compositions of Nannochloropsis oculata. The dissolved inorganic carbon (DIC) concentration in the three treatments decreased sharply during the first 6 days, and the percentage of dissolved organic carbon (DOC) (% of total organic carbon (TOC)) decreased with the depletion of the DIC. The NO(3)(-) assimilation of the algae was correlated with the DIC concentration. The algae in the highest DIC treatment had the highest specific grow rate (0.0843 d(-1)) (P<0.0001), and their biomass and fatty acid methyl esters (FAME) productivity were 84.00 and 9.69 mg/L/d, respectively (P<0.0001). Contents of C16 and C18 series (% of FAME) were high and the C16:0 increased with the decrease of C18:1 during the cultivation. The iodine value (IV) of the algae was low at the low DIC media.

  4. The high-affinity phosphate-binding protein PstS is accumulated under high fructose concentrations and mutation of the corresponding gene affects differentiation in Streptomyces lividans.

    PubMed

    Díaz, Margarita; Esteban, Ana; Fernández-Abalos, José Manuel; Santamaría, Ramón I

    2005-08-01

    The secreted protein pattern of Streptomyces lividans depends on the carbon source present in the culture media. One protein that shows the most dramatic change is the high-affinity phosphate-binding protein PstS, which is strongly accumulated in the supernatant of liquid cultures containing high concentrations (>3 %) of certain sugars, such as fructose, galactose and mannose. The promoter region of this gene and that of its Streptomyces coelicolor homologue were used to drive the expression of a xylanase in S. lividans that was accumulated in the culture supernatant when grown in the presence of fructose. PstS accumulation was dramatically increased in a S. lividans polyphosphate kinase null mutant (Deltappk) and was impaired in a deletion mutant lacking phoP, the transcriptional regulator gene of the two-component phoR-phoP system that controls the Pho regulon. Deletion of the pstS genes in S. lividans and S. coelicolor impaired phosphate transport and accelerated differentiation and sporulation on solid media. Complementation with a single copy in a S. lividans pstS null mutant returned phosphate transport and sporulation to levels similar to those of the wild-type strain. The present work demonstrates that carbon and phosphate metabolism are linked in the regulation of genes and that this can trigger the genetic switch towards morphogenesis.

  5. Carvacrol and rosemary oil at higher concentrations induce apoptosis in human hepatoma HepG2 cells

    PubMed Central

    Melušová, Martina; Jantová, Soňa

    2014-01-01

    Natural essential oils are volatile herbal complex compounds which manifest cytotoxic effects on living cells depending on their type and concentration but usually they are not genotoxic. Our previous studies showed that carvacrol (CA) and rosemary essential oil (RO) induced growth inhibition of both human cell lines HepG2 and BHNF-1, with hepatoma HepG2 cells being more sensitive to either compound tested. Cytotoxic concentrations of CA and RO induced the formation of DNA strand breaks. Further ex vivo studies showed that extracts prepared from hepatocytes of CA- and RO-supplemented rats did not increase incision repair activity compared to extracts from liver cells of control animals. Therefore, the aim of this work was to determine the effect of cytotoxic concentrations of CA and RO on the cell cycle and the ability of both natural volatiles to induce DNA fragmentation and apoptotic death of human hepatoma HepG2 cells. These effects were measured after 24 h incubation of HepG2 cells with CA and RO using three independent methods – flow cytometry, internucleosomal DNA fragmentation (electrophoresis) and micronucleus assay. Evaluation of morphological changes and formation of micronuclei in HepG2 cells showed no increase in the number of micronuclei in cells treated by CA and RO compared to control cells. On the other hand, CA and RO induced morphological changes typical for apoptosis in concentration-dependent manner. The presence of necrosis was negligible. Both natural compounds caused shrinking of cytoplasmic membrane and formation of apoptotic bodies. In addition, the highest concentrations of CA and RO induced internucleosomal DNA fragmentation (formation of DNA ladder) in HepG2 cells. Cell cycle analysis revealed the accumulation of cells in the G1 phase, which was accompanied by a reduction in the number of cells in the S phase after 24 h exposure to the substances tested. The cell division was thus slowed down or stopped and this process resulted in

  6. Metal debris concentrations in soft tissues adjacent to loosened femoral stems is higher in uncemented than cemented implants

    PubMed Central

    2014-01-01

    Background There are still many questions related to aseptic femoral stem loosening. Systemic and local immune responses to the implanted “foreign body” is one of the reasons for loosening. The purpose of the study was to measure metal ion concentration (Ti, Co, Cr, Mo, Ni, Al) around loosened femoral stems and compare their levels around uncemented and cemented implants. Methods This paper reports 50 hips operated for isolated stem loosening, in 50 patients at the mean age of 57 years (from 21 to 87). There were 25 cemented (Co,Cr29,Mo,Ni) and 25 uncemented (Ti, Al) stems. The mean follow-up from primary hip replacement to revision was 10.1 years (from 0.5 to 17). During the procedure, scar tissue around the stem was taken for analysis of metal ions. Results The concentrations of titanium and aluminium in soft tissues around uncemented loosened stems were higher than cemented ones (p < 0.001, p < 0.001 respectively). However, no statistically significant differences were observed between both types of stems in terms of ions of the metal of which cemented implants had been made of (Co, Cr, Mo, Ni). Conclusions In soft tissue around a loosened stem, the concentrations of metal ions from implants are much higher in case of uncemented stems than of cemented ones. Metal ions from vitalium femoral heads were found around uncemented stems in similar values to cemented streams. PMID:25098913

  7. Concentrations and environmental fate of Ra in cation-exchange regeneration brine waste disposed to septic tanks and accumulation in sludge, New Jersey Coastal Plain, USA.

    PubMed

    Szabo, Zoltan; Jacobsen, Eric; Kraemer, Thomas F; Parsa, Bahman

    2008-06-01

    Concentrations of Ra in liquid and solid wastes generated from 15 softeners treating domestic well waters from New Jersey Coastal Plain aquifers (where combined Ra ((226)Ra plus (228)Ra) concentrations commonly exceed 0.185 Bq L(-1)) were determined. Softeners, when maintained, reduced combined Ra about 10-fold (<0.024 Bq L(-1)). Combined Ra exceeded 0.185 Bq L(-1) at 1 non-maintained system. Combined Ra was enriched in regeneration brine waste (maximum, 81.2 Bq L(-1)), but concentrations in septic-tank effluents receiving brine waste were less than in the untreated ground waters. The maximum combined Ra concentration in aquifer sands (40.7 Bq kg(-1) dry weight) was less than that in sludge from the septic tanks (range, 84-363 Bq kg(-1)), indicating Ra accumulation in sludge from effluent. The combined Ra concentration in sludge from the homeowners' septic systems falls within the range reported for sludge samples from publicly owned treatment works within the region.

  8. Concentrations and environmental fate of Ra in cation-exchange regeneration brine waste disposed to septic tanks and accumulation in sludge, New Jersey Coastal Plain, USA

    USGS Publications Warehouse

    Szabo, Z.; Jacobsen, E.; Kraemer, T.F.; Parsa, B.

    2008-01-01

    Concentrations of Ra in liquid and solid wastes generated from 15 softeners treating domestic well waters from New Jersey Coastal Plain aquifers (where combined Ra (226Ra plus 228Ra) concentrations commonly exceed 0.185 Bq L-1) were determined. Softeners, when maintained, reduced combined Ra about 10-fold (<0.024 Bq L-1). Combined Ra exceeded 0.185 Bq L-1 at 1 non-maintained system. Combined Ra was enriched in regeneration brine waste (maximum, 81.2 Bq L-1), but concentrations in septic-tank effluents receiving brine waste were less than in the untreated ground waters. The maximum combined Ra concentration in aquifer sands (40.7 Bq kg-1 dry weight) was less than that in sludge from the septic tanks (range, 84-363 Bq kg-1), indicating Ra accumulation in sludge from effluent. The combined Ra concentration in sludge from the homeowners' septic systems falls within the range reported for sludge samples from publicly owned treatment works within the region.

  9. Accumulate repeat accumulate codes

    NASA Technical Reports Server (NTRS)

    Abbasfar, Aliazam; Divsalar, Dariush; Yao, Kung

    2004-01-01

    In this paper we propose an innovative channel coding scheme called 'Accumulate Repeat Accumulate codes' (ARA). This class of codes can be viewed as serial turbo-like codes, or as a subclass of Low Density Parity Check (LDPC) codes, thus belief propagation can be used for iterative decoding of ARA codes on a graph. The structure of encoder for this class can be viewed as precoded Repeat Accumulate (RA) code or as precoded Irregular Repeat Accumulate (IRA) code, where simply an accumulator is chosen as a precoder. Thus ARA codes have simple, and very fast encoder structure when they representing LDPC codes. Based on density evolution for LDPC codes through some examples for ARA codes, we show that for maximum variable node degree 5 a minimum bit SNR as low as 0.08 dB from channel capacity for rate 1/2 can be achieved as the block size goes to infinity. Thus based on fixed low maximum variable node degree, its threshold outperforms not only the RA and IRA codes but also the best known LDPC codes with the dame maximum node degree. Furthermore by puncturing the accumulators any desired high rate codes close to code rate 1 can be obtained with thresholds that stay close to the channel capacity thresholds uniformly. Iterative decoding simulation results are provided. The ARA codes also have projected graph or protograph representation that allows for high speed decoder implementation.

  10. Co-digestion of concentrated black water and kitchen refuse in an accumulation system within the DESAR (decentralized sanitation and reuse) concept.

    PubMed

    Kujawa-Roeleveld, K; Elmitwalli, T; Gaillard, A; van Leeuwen, M; Zeeman, G

    2003-01-01

    Co-digestion of concentrated black water and kitchen refuse within the DESAR concept was the objective of this pilot research. The digestion took place in two, non-mixed accumulation reactors (AC1 and AC2) inoculated with digested primary sludge from a WWTP at a temperature of 20 degrees C for a period of around 150 days. Reactor AC1 was fed with a mixture of faeces, urine and kitchen refuse in the equivalent amount that one individual generates per day. The AC2 was fed with a mixture of faeces and kitchen refuse in the equivalent amount that two individuals produce per day. Some contribution of urine to AC2 was not to be avoided. Detailed characterisation of waste(water) was performed. The performance of the stratified reactor was followed by monitoring the reactor content for several reactors' heights as well as being based on the biogas production. In general the system exposed good process stability. The methanisation of 34 and 61% was obtained for AC1 and AC2 respectively. The biogas yield was 26.5 and 50.8 L/p/d for the respective reactors. Proper choice of inoculum as well as good buffering capacity did not lead to accumulation of VFA and an inhibitive effect due to relatively high ammonium concentration. The chosen process is a promising technology showing good process stability especially for high strength influent.

  11. The Accumulative Effect of Concentric-Biased and Eccentric-Biased Exercise on Cardiorespiratory and Metabolic Responses to Subsequent Low-Intensity Exercise: A Preliminary Study

    PubMed Central

    Gavin, James Peter; Myers, Stephen; Willems, Mark Elisabeth Theodorus

    2015-01-01

    The study investigated the accumulative effect of concentric-biased and eccentric-biased exercise on cardiorespiratory, metabolic and neuromuscular responses to low-intensity exercise performed hours later. Fourteen young men cycled at low-intensity (~60 rpm at 50% maximal oxygen uptake) for 10 min before, and 12 h after: concentric-biased, single-leg cycling exercise (CON) (performed ~19:30 h) and eccentric-biased, double-leg knee extension exercise (ECC) (~06:30 h the following morning). Respiratory measures were sampled breath-by-breath, with oxidation values derived from stoichiometry equations. Knee extensor neuromuscular function was assessed before and after CON and ECC. Cardiorespiratory responses during low-intensity cycling were unchanged by accumulative CON and ECC. The RER was lower during low-intensity exercise 12 h after CON and ECC (0.88 ± 0.08), when compared to baseline (0.92 ± 0.09; p = 0.02). Fat oxidation increased from baseline (0.24 ± 0.2 g·min−1) to 12 h after CON and ECC (0.39 ± 0.2 g·min−1; p = 0.01). Carbohydrate oxidation decreased from baseline (1.59 ± 0.4 g·min−1) to 12 h after CON and ECC (1.36 ± 0.4 g·min−1; p = 0.03). These were accompanied by knee extensor force loss (right leg: −11.6%, p < 0.001; left leg: −10.6%, p = 0.02) and muscle soreness (right leg: 2.5 ± 0.9, p < 0.0001; left leg: 2.3 ± 1.2, p < 0.01). Subsequent concentric-biased and eccentric-biased exercise led to increased fat oxidation and decreased carbohydrate oxidation, without impairing cardiorespiration, during low-intensity cycling. An accumulation of fatiguing and damaging exercise increases fat utilisation during low intensity exercise performed as little as 12 h later. PMID:26839613

  12. The Accumulative Effect of Concentric-Biased and Eccentric-Biased Exercise on Cardiorespiratory and Metabolic Responses to Subsequent Low-Intensity Exercise: A Preliminary Study.

    PubMed

    Gavin, James Peter; Myers, Stephen; Willems, Mark Elisabeth Theodorus

    2015-12-22

    The study investigated the accumulative effect of concentric-biased and eccentric-biased exercise on cardiorespiratory, metabolic and neuromuscular responses to low-intensity exercise performed hours later. Fourteen young men cycled at low-intensity (~60 rpm at 50% maximal oxygen uptake) for 10 min before, and 12 h after: concentric-biased, single-leg cycling exercise (CON) (performed ~19:30 h) and eccentric-biased, double-leg knee extension exercise (ECC) (~06:30 h the following morning). Respiratory measures were sampled breath-by-breath, with oxidation values derived from stoichiometry equations. Knee extensor neuromuscular function was assessed before and after CON and ECC. Cardiorespiratory responses during low-intensity cycling were unchanged by accumulative CON and ECC. The RER was lower during low-intensity exercise 12 h after CON and ECC (0.88 ± 0.08), when compared to baseline (0.92 ± 0.09; p = 0.02). Fat oxidation increased from baseline (0.24 ± 0.2 g·min(-1)) to 12 h after CON and ECC (0.39 ± 0.2 g·min(-1); p = 0.01). Carbohydrate oxidation decreased from baseline (1.59 ± 0.4 g·min(-1)) to 12 h after CON and ECC (1.36 ± 0.4 g·min(-1); p = 0.03). These were accompanied by knee extensor force loss (right leg: -11.6%, p < 0.001; left leg: -10.6%, p = 0.02) and muscle soreness (right leg: 2.5 ± 0.9, p < 0.0001; left leg: 2.3 ± 1.2, p < 0.01). Subsequent concentric-biased and eccentric-biased exercise led to increased fat oxidation and decreased carbohydrate oxidation, without impairing cardiorespiration, during low-intensity cycling. An accumulation of fatiguing and damaging exercise increases fat utilisation during low intensity exercise performed as little as 12 h later.

  13. Hair cortisol concentrations in higher- and lower-stress mother-daughter dyads: A pilot study of associations and moderators.

    PubMed

    Ouellette, Sarah J; Russell, Evan; Kryski, Katie R; Sheikh, Haroon I; Singh, Shiva M; Koren, Gideon; Hayden, Elizabeth P

    2015-07-01

    Hair cortisol concentrations (HCC) are receiving increased attention as a novel biomarker of psychophysiological responses to chronic stress, with potential relevance for psychopathology risk research. We examined the validity of HCC as a marker of psychosocial stress in mother (M(age)  = 37.87 years)-daughter (M(age)  = 7.62 years) dyads characterized by higher (n = 30) or lower (n = 30) maternal chronic stress. Additionally, we examined whether early care moderated similarity of HCC levels within dyads. Higher-stress mothers had significantly lower HCC compared to lower-stress mothers, consistent with other research showing that chronic stress leads to blunted HPA axis activity over time. Further, HCC in daughters were significantly and positively associated with previously assessed salivary cortisol stress reactivity. Finally, mother-daughter HCC associations were significantly moderated by negative parenting styles, such that associations became stronger as quality of parenting decreased. Findings overall indicate that HCC may be a useful marker of cortisol responses to chronic stress.

  14. Lower fracture risk in older men with higher sclerostin concentration: a prospective analysis from the MINOS study.

    PubMed

    Szulc, Pawel; Bertholon, Cindy; Borel, Olivier; Marchand, Francois; Chapurlat, Roland

    2013-04-01

    Sclerostin is synthesized by osteocytes and inhibits bone formation. We measured serum sclerostin levels in 710 men aged 50 years and older. Bone mineral density (BMD) was measured at the lumbar spine, hip, and distal forearm. Serum sclerostin increased with age (unadjusted r = 0.30, p < 0.001). After adjustment for age, weight, and bioavailable 17β-estradiol, serum sclerostin correlated positively with BMD (r = 0.24 to 0.35, p < 0.001) and negatively with the levels of bone turnover markers (r = - 0.09 to - 0.23, p < 0.05 to 0.001). During a 10-year follow-up, 75 men sustained fragility fractures. Fracture risk was lower in the two upper quintiles of sclerostin combined versus three lower quintiles combined (6.1 versus 13.5%, p < 0.01). We compared fracture risk in the two highest quintiles combined versus three lower quintiles combined using the Cox model adjusted for age, weight, leisure physical activity, BMD, bone width (tubular bones), prevalent fracture, prevalent falls, ischemic heart disease, and severe abdominal aortic calcification. Men with higher sclerostin concentration had lower fracture risk (adjusted for hip BMD, hazard ratio [HR] = 0.55, 95% confidence interval [CI] 0.31 to 0.96, p < 0.05). The results were similar in 47 men with major fragility fractures (adjusted for lumbar spine BMD: HR = 0.39, 95% CI 0.17 to 0.90, p < 0.05). Men who had higher sclerostin and higher BMD (two highest quintiles) had lower risk of fracture compared with men who had lower BMD and lower sclerostin levels (three lower quintiles) (HR = 0.24, 95% CI 0.10 to 0.62, p < 0.005). Circulating sclerostin was not associated with mortality rate or the incidence of major cardiovascular events. Thus, in older men, higher serum sclerostin levels are associated with lower risk of fracture, higher BMD, and lower bone turnover rate. PMID:23165952

  15. Si-Accumulation In Artemisia annua Glandular Trichomes Increases Artemisinin Concentration, but Does Not Interfere In the Impairment of Toxoplasma gondii Growth

    PubMed Central

    Rostkowska, Cristina; Mota, Caroline M.; Oliveira, Taísa C.; Santiago, Fernanda M.; Oliveira, Lilian A.; Korndörfer, Gaspar H.; Lana, Regina M. Q.; Rossi, Monica L.; Nogueira, Neusa L.; Simonnet, Xavier; Mineo, Tiago W. P.; Silva, Deise A.O.; Mineo, José R.

    2016-01-01

    Artemisia annua is used as a source of artemisinin, a potent therapeutic agent used for the treatment of infectious diseases, chiefly malaria. However, the low concentration (from 0.01 to 1.4% of dried leaf matter) of artemisinin in the plant obtained with the traditional cropping system makes it a relatively expensive drug, especially in developing countries. Considering that artemisinin and silicon (Si) are both stored in A. annua glandular trichomes, and that Si accumulation has never been investigated, this study aimed to look into Si effects on A. annua trichome artemisinin concentration, and whether leaf infusion from Si-treated A. annua plants is able to control Toxoplasma gondii growth. T. gondii is the etiologic agent of toxoplasmosis, a zoonotic parasitic disease whose traditional treatment shows significant side effects. The experimental design consisted of A. annua seedlings randomly planted in soil treated with different doses of calcium/magnesium silicate (0, 200, 400, 800, and 1600 kg ha-1). Analysis of foliar macronutrients showed significant increases of nitrogen content only at the highest dose of silicate. Foliar micronutrients, Si concentrations, and plant height were not affected by any of the silicate doses. However, the dose of 400 kg ha-1 of silicate increased the trichome size, which in turn raised artemisinin concentration in leaves and the infusion. In contrast, the 800 and 1600 kg ha-1 doses dramatically decreased artemisinin concentration. HeLa cell treatment with the infusion of A. annua grown in soil treated with 400 kg ha-1 of silicate decreased parasite proliferation in a dose-dependent manner when the treatment was carried out after or along with T. gondii infection. However, this effect was similar to A. annua grown in soil without silicate treatment. Thus, it can be concluded that, even though Si applied to the soil at 400 kg ha-1 has a positive effect on the A. annua glandular trichome size and the artemisinin concentration

  16. Linking environmental heavy metal concentrations and salinity gradients with metal accumulation and their effects: A case study in 3 mussel species of Vitória estuary and Espírito Santo bay, Southeast Brazil.

    PubMed

    Kumar, Vikas; Sinha, Amit Kumar; Rodrigues, Paulo Pinheiro; Mubiana, Valentine K; Blust, Ronny; De Boeck, Gudrun

    2015-08-01

    The present study was conducted to link the heavy metal load in three species of mussels (Perna perna, Mytella falcata and Mytella guyanensis) from the estuaries and bays around Vitória island, south-east of Brazil, with the salinity gradient and the heavy metal levels in the abiotic environment (including water, suspended particulate matter (SPM) and sediment). Primarily based on the salinity gradient, a total of 26 sites around Vitória Island were selected for sampling of water, SPM, sediments and organisms. Besides tissue metal levels, the condition index and energy stores (glycogen, lipid and protein) were quantified as an indicator of fitness in response to metal pollution. Dissolved metals in water indicate that Cd and Mn content was higher along Espírito Santo Bay, while Al, Co, Cu, Cr and Fe were elevated in the sites with low salinity such as river mouths, estuarine and sewage canals. Likewise, suspended matter sampled from low salinity sites showed a higher heavy metal load compared to moderate and high salinity sites. Though mussels were sampled from different sites, the contamination for Cd, Cu, Fe and Mn was higher in mussels inhabiting low salinity sites (M. guyanensis and M. falcata) compared to P. perna, a high saline water inhabitant. However, a higher Zn body burden was observed for P. perna compared to Mytella species. Tissue Fe accumulation (but not Mn and Zn) correlated with heavy metal levels in suspended material for all three species, and for M. falcata this correlation also existed for Cd and Cu. Energy store and condition index in all mussels varied depending on the sampling sites and correlated with salinity gradient rather than tissue metal concentration. Overall, metal concentration in mussels did not exceed the safe levels as per the international standards for metals, and would be of no risk for human consumption.

  17. C-reactive Protein Concentration Is Associated With a Higher Risk of Mortality in a Rural Korean Population

    PubMed Central

    Kim, Mi Kyung; Shin, Min-Ho; Shin, Dong Hoon; Koh, Sang-Baek; Ahn, Song Vogue; Lee, Tae-Yong; Ryu, So Yeon; Song, Jae-Sok; Choe, Hong-Soon; Lee, Young-Hoon

    2016-01-01

    Objectives C-reactive protein (CRP), an inflammatory biomarker, has been widely used as a preclinical marker predictive of morbidity and mortality. Although many studies have reported a positive association between CRP and mortality, uncertainty still remains about this association in various populations, especially in rural Korea. Methods A total of 23 233 middle-aged participants (8862 men and 14 371 women) who were free from cardiovascular disease, cancer, and acute inflammation (defined by a CRP level ≥10 mg/L) were drawn from 11 rural communities in Korea between 2005 and 2011. Blood CRP concentration was analyzed as a categorical variable (low: 0.0-0.9 mg/L; intermediate: 1.0-3.0 mg/L; high: 3.1-9.9 mg/L) as well as a continuous variable. Each participant’s vital status through December 2013 was confirmed by death statistics from the National Statistical Office. Cox proportional hazard models were used to assess the independent association between CRP and mortality after adjusting for other risk factors. Results The total quantity of observed person-years was 57 975 for men and 95 146 for women, and the number of deaths was 649 among men and 367 among women. Compared to the low-CRP group, the adjusted hazard ratio for all-cause mortality of the intermediate group was 1.17 (95% confidence interval [CI], 0.98 to 1.40) for men and 1.27 (95% CI, 1.01 to 1.61) for women, and the corresponding values for the high-CRP group were 1.98 (95% CI, 1.61 to 2.42) for men and 1.41 (95% CI, 1.03 to 1.95) for women. Similar trends were found for CRP evaluated as a continuous variable and for cardiovascular mortality. Conclusions Higher CRP concentrations were associated with higher mortality in a rural Korean population, and this association was more prominent in men than in women. PMID:27744669

  18. Higher initial tacrolimus blood levels and concentration-dose ratios in kidney transplant recipients who develop diabetes mellitus.

    PubMed

    Rodrigo, E; de Cos, M A; Fernández-Fresnedo, G; Sánchez, B; Ruiz, J C; Piñera, C; Palomar, R; Cotorruelo, J G; Gómez-Alamillo, C; de Castro, S Sanz; de Francisco, A L M; Arias, M

    2005-11-01

    Posttransplantation diabetes mellitus (PTDM) is a common complication of kidney transplantation, associated with poorer graft and patient outcomes. Tacrolimus is a strong immunosuppressive drug associated with low acute rejection rates, but a higher risk for PTDM. High trough levels of tacrolimus during the first month after transplantation have been found to be a significant risk factor for the development of PTDM. The aim of this single-center study was to identify the risk factors for the development of PTDM among kidney transplant recipients under tacrolimus therapy. We examined 73 cadaveric kidney transplant recipients receiving tacrolimus between 1994 and 2003. Age, donor and recipient gender, dialysis method, body mass index (BMI), first year weight gain, mismatches, incidence of acute rejection and delayed graft function, hepatitis C serology, first year cumulative steroid dose, first tacrolimus blood level, first tacrolimus blood level <15 ng/mL, and corresponding tacrolimus daily doses and concentration/dose ratios (CDR) were also collected. PTDM was defined as at least 2 fasting blood glucose values > or =126 mg/dL, according to the World Health Organization criteria. Incidence of first year PTDM was 27.4%. Patients with PTDM showed significantly higher age, BMI, first tacrolimus blood level, first tacrolimus CDR, and CDR with tacrolimus blood level <15 ng/mL as well as less 1-year weight gain. After logistic regression, age (relative risk [RR] 1.060, confidence interval [CI] 95%, 1.001-1.122; P = .043) and first tacrolimus blood level (RR 1.154; CI 95%, 1.038-1.283; P = .008) remain significant risk factors for developing PTDM. Older age and initial tacrolimus blood levels were the main risk factors for PTDM among our group of patients. Kidney transplant recipients who develop PTDM maintain a high CDR of tacrolimus.

  19. Higher baseline irisin concentrations are associated with greater reductions in glycemia and insulinemia after weight loss in obese subjects

    PubMed Central

    Lopez-Legarrea, P; de la Iglesia, R; Crujeiras, A B; Pardo, M; Casanueva, F F; Zulet, M A; Martinez, J A

    2014-01-01

    Irisin is assumed to be a relevant link between muscle and weight maintenance as well as to mediate exercise benefits on health. The aim of this study was to assess the possible associations between irisin levels and glucose homeostasis in obese subjects with metabolic syndrome (MetS) following an energy-restricted treatment. Ninety-six adults with excessive body weight and MetS features underwent a hypocaloric dietary pattern for 8 weeks, within the RESMENA randomized controlled trial (www.clinicaltrials.gov; NCT01087086). After the intervention, dietary restriction significantly reduced body weight and evidenced a dietary-induced decrease in circulating levels of irisin in parallel with improvements on glucose homeostasis markers. Interestingly, participants with higher irisin values at baseline (above the median) showed a greater reduction on glucose (P=0.022) and insulin (P=0.021) concentrations as well as on the homeostasis model assessment index (P=0.008) and triglycerides (P=0.006) after the dietary intervention, compared with those presenting low-irisin baseline values (below the median). Interestingly, a positive correlation between irisin and carbohydrate intake was found at the end of the experimental period. In conclusion, irisin appears to be involved in glucose metabolism regulation after a dietary-induced weight loss. PMID:24567125

  20. Amazonian mid- to high-latitude glaciation on Mars: Supply-limited ice sources, ice accumulation patterns, and concentric crater fill glacial flow and ice sequestration

    NASA Astrophysics Data System (ADS)

    Fastook, James L.; Head, James W.

    2014-02-01

    Concentric crater fill (CCF) occurs in the interior of impact craters in mid- to high latitudes on Mars and is interpreted to have formed by glacial ice flow and debris covering. We use the characteristics and orientation of deposits comprising CCF, the thickness of pedestal deposits in mid- to high-latitude pedestal craters (Pd), the volumes of the current polar caps, and information about regional slopes and ice rheology to address questions about (1) the maximum thickness of regional ice deposits during the Late Amazonian, (2) the likelihood that these deposits flowed regionally, (3) the geological regions and features most likely to induce ice-flow, and (4) the locations and environments in which ice is likely to have been sequestered up to the present. We find that regional ice flow under Late Amazonian climate conditions requires ice thicknesses exceeding many hundreds of meters for slopes typical of the vast majority of the surface of Mars, a thickness for the mid-latitudes that is well in excess of the total volume available from polar ice reservoirs. This indicates that although conditions for mid- to high-latitude glaciation may have persisted for tens to hundreds of millions of years, the process is “supply limited”, with a steady state reached when the polar ice cap water ice supply becomes exhausted. Impact craters are by far the most abundant landform with associated slopes (interior wall and exterior rim) sufficiently high to induce glacial ice flow under Late Amazonian climate conditions, and topographic slope data show that Amazonian impact craters have been clearly modified, undergoing crater interior slope reduction and floor shallowing. We show that these trends are the predictable response of ice deposition and preferential accumulation and retention in mid- to high-latitude crater interiors during episodes of enhanced spin-axis obliquity. We demonstrate that flow from a single episode of an inter-crater terrain layer comparable to Pedestal

  1. Increasing sulfate concentrations result in higher sulfide production and phosphorous mobilization in a shallow eutrophic freshwater lake.

    PubMed

    Chen, Mo; Li, Xiao-Hong; He, Yu-Hong; Song, Na; Cai, Hai-Yuan; Wang, Changhui; Li, Yun-Tao; Chu, Hai-Yan; Krumholz, Lee R; Jiang, He-Long

    2016-06-01

    Increasing sulfate input has been seen as an issue in management of aquatic ecosystems, but its influences on eutrophic freshwater lakes is not clear. In this study, it was observed that increasing sulfate concentration without additional cyanobacterial bloom biomass (CBB) addition did not have an obvious effect on element cycling during 1-year continuous flow mesocosm experiments in which water and sediments were taken from a shallow eutrophic lake with sulfate levels near 1 mM. However, following addition of CBB to mesocosms, sulfate-reducing bacteria (SRB) were observed in the water column, and increasing numbers of SRB in the water column were associated with higher sulfate input. Sulfate amendment (0-70 mg L(-1)) also resulted in a larger amount of total dissolved sulfide (peak values of 5.90 ± 0.36 to 7.60 ± 0.12 mg L(-1)) in the water column and acid volatile sulfide (1081.71 ± 69.91 to 1557.98 ± 41.72 mg kg(-1)) in 0-1 cm surface sediments due to sulfate reduction. During the period of CBB decomposition, increasing sulfate levels in the water column were positively correlated with increasing diffusive phosphate fluxes of 1.23 ± 0.32 to 2.17 ± 0.01 mg m(-2) d(-1) at the water-sediment interface. As increases in sulfide and phosphate release rates deteriorated the water quality/ecosystem and even spurred the occurrence of a black water problem in lakes, the control of sulfate input level should be considered for shallow eutrophic lake management, especially during cyanobacterial bloom periods. PMID:27023925

  2. Accumulate-Repeat-Accumulate-Accumulate Codes

    NASA Technical Reports Server (NTRS)

    Divsalar, Dariush; Dolinar, Samuel; Thorpe, Jeremy

    2007-01-01

    Accumulate-repeat-accumulate-accumulate (ARAA) codes have been proposed, inspired by the recently proposed accumulate-repeat-accumulate (ARA) codes. These are error-correcting codes suitable for use in a variety of wireless data-communication systems that include noisy channels. ARAA codes can be regarded as serial turbolike codes or as a subclass of low-density parity-check (LDPC) codes, and, like ARA codes they have projected graph or protograph representations; these characteristics make it possible to design high-speed iterative decoders that utilize belief-propagation algorithms. The objective in proposing ARAA codes as a subclass of ARA codes was to enhance the error-floor performance of ARA codes while maintaining simple encoding structures and low maximum variable node degree.

  3. Atmospheric mercury accumulation and washoff processes on impervious urban surfaces

    USGS Publications Warehouse

    Eckley, C.S.; Branfireun, B.; Diamond, M.; Van Metre, P.C.; Heitmuller, F.

    2008-01-01

    The deposition and transport of mercury (Hg) has been studied extensively in rural environments but is less understood in urbanized catchments, where elevated atmospheric Hg concentrations and impervious surfaces may efficiently deliver Hg to waterways in stormwater runoff. We determined the rate at which atmospheric Hg accumulates on windows, identified the importance of washoff in removing accumulated Hg, and measured atmospheric Hg concentrations to help understand the relationship between deposition and surface accumulation. The main study location was Toronto, Ontario. Similar samples were also collected from Austin, Texas for comparison of Hg accumulation between cities. Windows provided a good sampling surface because they are ubiquitous in urban environments and are easy to clean/blank allowing the assessment of contemporary Hg accumulation. Hg Accumulation rates were spatially variable ranging from 0.82 to 2.7 ng m-2 d-1 in Toronto and showed similar variability in Austin. The highest accumulation rate in Toronto was at the city center and was 5?? higher than the rural comparison site (0.58 ng m-2 d-1). The atmospheric total gaseous mercury (TGM) concentrations were less than 2?? higher between the rural and urban locations (1.7 ?? 0.3 and 2.7 ?? 1.1 ng m-3, respectively). The atmospheric particulate bound fraction (HgP), however, was more than 3?? higher between the rural and urban sites, which may have contributed to the higher urban Hg accumulation rates. Windows exposed to precipitation had 73 ?? 9% lower accumulation rates than windows sheltered from precipitation. Runoff collected from simulated rain events confirmed that most Hg accumulated on windows was easily removed and that most of the Hg in washoff was HgP. Our results indicate that the Hg flux from urban catchments will respond rapidly to changes in atmospheric concentrations due to the mobilization of the majority of the surface accumulated Hg during precipitation events. ?? 2008 Elsevier

  4. Accumulation of DOC in Low Phosphate Low Chlorophyll (LPLC) area: is it related to higher production under high N:P ratio?

    NASA Astrophysics Data System (ADS)

    Mauriac, R.; Moutin, T.; Baklouti, M.

    2010-09-01

    The biogeochemistry of carbon and nutrients (N, P) in the surface layer of the ocean strongly depends on the interaction between C, N and P at the cell level and at the population level where interaction between primary producers (phytoplankton) and remineralizers (heterotrophic bacteria) impact the overall stock and dynamics of organic carbon. To understand these interactions in the surface layer of the Mediterranean Sea, we implemented, using Eco3M, a multi-element, steady state, mechanistic model. This cell-based model intend to represent the growth of phytoplankton and heterotrophic bacteria under various amount of nutrients. As a results, it displays the expected biogeochemical characteristics of the system and give us insight on the expected interaction between phytoplankton and heterotrophic bacteria both in term of competition for inorganic nutrients and in term of commensalism for organic carbon. In this study, we found a good quantitative agreement between model results and literrature data for stocks and fluxes of the western Mediterranean basin. In addition, for phytoplankton we show how the uncoupling between carbon production and growth could impact the overall DOC dynamic and based on these results, we proposed a new explanantion for the observed DOC accumulation in the surface layer of the Mediterranean Sea.

  5. Higher Serum 25-Hydroxyvitamin D Concentrations Associate with a Faster Recovery of Skeletal Muscle Strength after Muscular Injury

    PubMed Central

    Barker, Tyler; Henriksen, Vanessa T.; Martins, Thomas B.; Hill, Harry R.; Kjeldsberg, Carl R.; Schneider, Erik D.; Dixon, Brian M.; Weaver, Lindell K.

    2013-01-01

    The primary purpose of this study was to identify if serum 25-hydroxyvitamin D (25(OH)D) concentrations predict muscular weakness after intense exercise. We hypothesized that pre-exercise serum 25(OH)D concentrations inversely predict exercise-induced muscular weakness. Fourteen recreationally active adults participated in this study. Each subject had one leg randomly assigned as a control. The other leg performed an intense exercise protocol. Single-leg peak isometric force and blood 25(OH)D, aspartate and alanine aminotransferases, albumin, interferon (IFN)-γ, and interleukin-4 were measured prior to and following intense exercise. Following exercise, serum 25(OH)D concentrations increased (p < 0.05) immediately, but within minutes, subsequently decreased (p < 0.05). Circulating albumin increases predicted (p < 0.005) serum 25(OH)D increases, while IFN-γ increases predicted (p < 0.001) serum 25(OH)D decreases. Muscular weakness persisted within the exercise leg (p < 0.05) and compared to the control leg (p < 0.05) after the exercise protocol. Serum 25(OH)D concentrations inversely predicted (p < 0.05) muscular weakness (i.e., control leg vs. exercise leg peak isometric force) immediately and days (i.e., 48-h and 72-h) after exercise, suggesting the attenuation of exercise-induced muscular weakness with increasing serum 25(OH)D prior to exercise. Based on these data, we conclude that pre-exercise serum 25(OH)D concentrations could influence the recovery of skeletal muscle strength after an acute bout of intense exercise. PMID:23595134

  6. Higher antioxidant and lower cadmium concentrations and lower incidence of pesticide residues in organically grown crops: a systematic literature review and meta-analyses.

    PubMed

    Barański, Marcin; Srednicka-Tober, Dominika; Volakakis, Nikolaos; Seal, Chris; Sanderson, Roy; Stewart, Gavin B; Benbrook, Charles; Biavati, Bruno; Markellou, Emilia; Giotis, Charilaos; Gromadzka-Ostrowska, Joanna; Rembiałkowska, Ewa; Skwarło-Sońta, Krystyna; Tahvonen, Raija; Janovská, Dagmar; Niggli, Urs; Nicot, Philippe; Leifert, Carlo

    2014-09-14

    Demand for organic foods is partially driven by consumers' perceptions that they are more nutritious. However, scientific opinion is divided on whether there are significant nutritional differences between organic and non-organic foods, and two recent reviews have concluded that there are no differences. In the present study, we carried out meta-analyses based on 343 peer-reviewed publications that indicate statistically significant and meaningful differences in composition between organic and non-organic crops/crop-based foods. Most importantly, the concentrations of a range of antioxidants such as polyphenolics were found to be substantially higher in organic crops/crop-based foods, with those of phenolic acids, flavanones, stilbenes, flavones, flavonols and anthocyanins being an estimated 19 (95 % CI 5, 33) %, 69 (95 % CI 13, 125) %, 28 (95 % CI 12, 44) %, 26 (95 % CI 3, 48) %, 50 (95 % CI 28, 72) % and 51 (95 % CI 17, 86) % higher, respectively. Many of these compounds have previously been linked to a reduced risk of chronic diseases, including CVD and neurodegenerative diseases and certain cancers, in dietary intervention and epidemiological studies. Additionally, the frequency of occurrence of pesticide residues was found to be four times higher in conventional crops, which also contained significantly higher concentrations of the toxic metal Cd. Significant differences were also detected for some other (e.g. minerals and vitamins) compounds. There is evidence that higher antioxidant concentrations and lower Cd concentrations are linked to specific agronomic practices (e.g. non-use of mineral N and P fertilisers, respectively) prescribed in organic farming systems. In conclusion, organic crops, on average, have higher concentrations of antioxidants, lower concentrations of Cd and a lower incidence of pesticide residues than the non-organic comparators across regions and production seasons. PMID:24968103

  7. Neuroprotective effects of chronic exposure of SH-SY5Y to low lithium concentration involve glycolysis stimulation, extracellular pyruvate accumulation and resistance to oxidative stress.

    PubMed

    Nciri, Riadh; Desmoulin, Frank; Allagui, Mohamed Saleh; Murat, Jean-Claude; Feki, Abdelfattah El; Vincent, Christian; Croute, Françoise

    2013-03-01

    Recent studies suggest that lithium protects neurons from death induced by a wide array of neurotoxic insults, stimulates neurogenesis and could be used to prevent age-related neurodegenerative diseases. In this study, SH-SY5Y human neuronal cells were cultured in the absence (Con) or in the presence (Li+) of a low lithium concentration (0.5 mm Li2CO3, i.e. 1 mm lithium ion) for 25-50 wk. In the course of treatment, growth rate of Con and Li+ cells was regularly analysed using Alamar Blue dye. Resistance to oxidative stress was investigated by evaluating: (1) the adverse effects of high concentrations of lithium (4-8 mm) or glutamate (20-90 mm) on cell growth rate; (2) the levels of lipid peroxidation (TBARS) and total glutathione; (3) the expression levels of the anti-apoptotic Bcl-2 protein. In addition, glucose metabolism was investigated by analysing selected metabolites in culture media and cell extracts by 1H-NMR spectroscopy. As compared to Con, Li+ cells multiplied faster and were more resistant to stress, as evidenced by a lower dose-dependent decrease of Alamar Blue reduction and dose-dependent increase of TBARS levels induced by toxic doses of lithium and glutamate. Total glutathione content and Bcl-2 level were increased in Li+ cells. Glucose consumption and glycolytic activity were enhanced in Li+ cells and an important release of pyruvate was observed. We conclude that chronic exposure to lithium induces adaptive changes in metabolism of SH-SY5Y cells involving a higher cell growth rate and a better resistance to oxidative stress.

  8. Crystallization of a perovskite film for higher performance solar cells by controlling water concentration in methyl ammonium iodide precursor solution

    NASA Astrophysics Data System (ADS)

    Adhikari, Nirmal; Dubey, Ashish; Gaml, Eman A.; Vaagensmith, Bjorn; Reza, Khan Mamun; Mabrouk, Sally Adel Abdelsalam; Gu, Shaopeng; Zai, Jiantao; Qian, Xuefeng; Qiao, Qiquan

    2016-01-01

    An optimal small amount of water added into methyl ammonium iodide (MAI) solution in isopropyl alcohol (IPA) helps perovskite crystallization and leads to larger grain size from sequential deposition of perovskite films. The concentration of water was varied from 1% to 7% (vol% of IPA) in MAI solution and optical absorption, crystallization, morphology of perovskite films and their photovoltaic performance were studied in perovskite solar cells. 5% by volume was found to lead to preferential crystallization in the (110) plane with grain size about three times that of perovskite films prepared without adding water into the MAI solution. The optimal water concentration of 5% by volume in the MAI solution led to average perovskite grain size of ~600 nm and solar cell efficiency of 12.42% at forward scan with a rate of 0.5 V s-1. Device performance decreases after increasing water concentration beyond 5% in the MAI solution due to formation of the PbI2 phase. Transient photocurrent and photovoltage measurements show the shortest charge transport time at 0.99 μs and the longest charge carrier life time at 13.6 μs for perovskite films prepared from 5% water in MAI solution, which improved perovskite solar cell efficiency from 9.04% to 12.42%.An optimal small amount of water added into methyl ammonium iodide (MAI) solution in isopropyl alcohol (IPA) helps perovskite crystallization and leads to larger grain size from sequential deposition of perovskite films. The concentration of water was varied from 1% to 7% (vol% of IPA) in MAI solution and optical absorption, crystallization, morphology of perovskite films and their photovoltaic performance were studied in perovskite solar cells. 5% by volume was found to lead to preferential crystallization in the (110) plane with grain size about three times that of perovskite films prepared without adding water into the MAI solution. The optimal water concentration of 5% by volume in the MAI solution led to average perovskite

  9. Crystallization of a perovskite film for higher performance solar cells by controlling water concentration in methyl ammonium iodide precursor solution.

    PubMed

    Adhikari, Nirmal; Dubey, Ashish; Gaml, Eman A; Vaagensmith, Bjorn; Reza, Khan Mamun; Mabrouk, Sally Adel Abdelsalam; Gu, Shaopeng; Zai, Jiantao; Qian, Xuefeng; Qiao, Qiquan

    2016-02-01

    An optimal small amount of water added into methyl ammonium iodide (MAI) solution in isopropyl alcohol (IPA) helps perovskite crystallization and leads to larger grain size from sequential deposition of perovskite films. The concentration of water was varied from 1% to 7% (vol% of IPA) in MAI solution and optical absorption, crystallization, morphology of perovskite films and their photovoltaic performance were studied in perovskite solar cells. 5% by volume was found to lead to preferential crystallization in the (110) plane with grain size about three times that of perovskite films prepared without adding water into the MAI solution. The optimal water concentration of 5% by volume in the MAI solution led to average perovskite grain size of ∼600 nm and solar cell efficiency of 12.42% at forward scan with a rate of 0.5 V s(-1). Device performance decreases after increasing water concentration beyond 5% in the MAI solution due to formation of the PbI2 phase. Transient photocurrent and photovoltage measurements show the shortest charge transport time at 0.99 μs and the longest charge carrier life time at 13.6 μs for perovskite films prepared from 5% water in MAI solution, which improved perovskite solar cell efficiency from 9.04% to 12.42%. PMID:26758661

  10. Crystallization of a perovskite film for higher performance solar cells by controlling water concentration in methyl ammonium iodide precursor solution.

    PubMed

    Adhikari, Nirmal; Dubey, Ashish; Gaml, Eman A; Vaagensmith, Bjorn; Reza, Khan Mamun; Mabrouk, Sally Adel Abdelsalam; Gu, Shaopeng; Zai, Jiantao; Qian, Xuefeng; Qiao, Qiquan

    2016-02-01

    An optimal small amount of water added into methyl ammonium iodide (MAI) solution in isopropyl alcohol (IPA) helps perovskite crystallization and leads to larger grain size from sequential deposition of perovskite films. The concentration of water was varied from 1% to 7% (vol% of IPA) in MAI solution and optical absorption, crystallization, morphology of perovskite films and their photovoltaic performance were studied in perovskite solar cells. 5% by volume was found to lead to preferential crystallization in the (110) plane with grain size about three times that of perovskite films prepared without adding water into the MAI solution. The optimal water concentration of 5% by volume in the MAI solution led to average perovskite grain size of ∼600 nm and solar cell efficiency of 12.42% at forward scan with a rate of 0.5 V s(-1). Device performance decreases after increasing water concentration beyond 5% in the MAI solution due to formation of the PbI2 phase. Transient photocurrent and photovoltage measurements show the shortest charge transport time at 0.99 μs and the longest charge carrier life time at 13.6 μs for perovskite films prepared from 5% water in MAI solution, which improved perovskite solar cell efficiency from 9.04% to 12.42%.

  11. Gaseous polycyclic aromatic hydrocarbon concentrations are higher in urban forests than adjacent open areas during summer but not in winter--Exploratory study.

    PubMed

    Viippola, Viljami; Rantalainen, Anna-Lea; Yli-Pelkonen, Vesa; Tervo, Peatta; Setälä, Heikki

    2016-01-01

    While the potential of plants to uptake polycyclic aromatic hydrocarbons (PAHs) is widely acknowledged, empirical evidence of the effects of this process on local atmospheric PAH concentrations and human health is tenuous. We measured gaseous PAH concentrations using passive samplers in urban tree-covered areas and adjacent open, treeless areas in a near-road environment in Finland to gain information on the ability of urban vegetation to improve air quality. The ability of urban, mostly deciduous, vegetation to affect PAHs was season dependent: during summer, concentrations were significantly higher in tree-covered areas, while in the fall, concentrations in open areas exceeded those in tree-covered areas. During winter, concentrations in tree-covered areas were either lower or did not differ from those in open areas. Results of this study imply that the commonly believed notion that trees unequivocally improve air quality does not apply to PAHs studied here.

  12. Gaseous polycyclic aromatic hydrocarbon concentrations are higher in urban forests than adjacent open areas during summer but not in winter--Exploratory study.

    PubMed

    Viippola, Viljami; Rantalainen, Anna-Lea; Yli-Pelkonen, Vesa; Tervo, Peatta; Setälä, Heikki

    2016-01-01

    While the potential of plants to uptake polycyclic aromatic hydrocarbons (PAHs) is widely acknowledged, empirical evidence of the effects of this process on local atmospheric PAH concentrations and human health is tenuous. We measured gaseous PAH concentrations using passive samplers in urban tree-covered areas and adjacent open, treeless areas in a near-road environment in Finland to gain information on the ability of urban vegetation to improve air quality. The ability of urban, mostly deciduous, vegetation to affect PAHs was season dependent: during summer, concentrations were significantly higher in tree-covered areas, while in the fall, concentrations in open areas exceeded those in tree-covered areas. During winter, concentrations in tree-covered areas were either lower or did not differ from those in open areas. Results of this study imply that the commonly believed notion that trees unequivocally improve air quality does not apply to PAHs studied here. PMID:26412199

  13. [Autochthonous yeasts isolated in Tenerife wines and their influence on ethyl acetate and higher alcohol concentrations analyzed by gas chromatography].

    PubMed

    Salvadores, M P; Díaz, M E; Cardell, E

    1993-12-01

    A taxonomic study of yeasts present on Tenerife wines, (Tacoronte-Acentejo Specific Denomination) has been carried out. Nine species of the genera: Saccharomyces, Torulaspora, Brettanomyces, Kluyveromyces, Debaryomyces, Saccharomycodes, Hansenula, Pichia and Candida have been isolated. Parallely we analysed volatile compounds of the wines such as ethyl acetate, methanol, isobutanol and amylic alcohols by gas chromatography. Appreciable quantities of ethyl acetate were detected due to the low fermentative power of species such as Candida glabrata and Debaryomyces hansenii. The greatest concentration of amylic alcohols were found in wines containing yeast with high alcohol producing power like Saccharomyces cerevisiae.

  14. Medium selection and effect of higher oxygen concentration pulses on Metarhizium anisopliae var. lepidiotum conidial production and quality.

    PubMed

    Tlecuitl-Beristain, Saul; Viniegra-González, Gustavo; Díaz-Godínez, Gerardo; Loera, Octavio

    2010-05-01

    Rice and oat flours were analyzed as media for the production of conidia by M. anisopliae var. lepidiotum. The presence of peptone increased conidia yield regardless of the substrate used; however, the highest yield was achieved on oat flour media. The effect of oxygen on conidia production using oat-peptone medium was also studied at two levels: Normal atmosphere (21% O(2)) and Oxygen-rich pulses (26% O(2)). Maximum conidia production (4.25 x 10(7) conidia cm(-2)) was achieved using 26% O(2) pulses after 156 h of culture, which was higher than 100% relative to conidial levels under normal atmosphere. Conidia yield per gram of biomass was 2.6 times higher with 26% O(2) (1.12 x 10(7) conidia mg(-1)). Conidia quality parameters, such as germination and hydrophobicity, did not show significant differences (P < 0.05) between those treatments. Bioassays parameters, using Tenebrio molitor adults, were analyzed for conidia obtained in both atmospheres and data were fitted to an exponential model. The specific mortality rates were 2.22 and 1.26 days(-1), whereas lethal times for 50% mortality were 3.90 and 4.31 days, for 26% O(2) pulses and 21% O(2) atmosphere, respectively. These results are relevant for production processes since an oxygen increase allowed superior levels of conidia by M. anisopliae without altering quality parameters and virulence toward Tenebrio molitor adults. PMID:20039138

  15. Sheep deficient in vitamin E preferentially select for a feed with a higher concentration of vitamin E.

    PubMed

    Amanoel, D E; Thomas, D T; Blache, D; Milton, J T B; Wilmot, M G; Revell, D K; Norman, H C

    2016-02-01

    Given the capacity of ruminants to modify diet selection based on metabolic needs, we hypothesised that, when given a choice, lambs experiencing a vitamin E deficiency would consume more of a vitamin E-enriched feed than lambs not deficient in vitamin E. Fifty-six Dohne Merino lambs were divided into two groups and fed either a vitamin E-deficient diet over 40 days to induce low plasma vitamin E or a vitamin E-enriched diet to induce high plasma vitamin E. The lambs were then offered a choice of vitamin E-enriched and vitamin E-deficient pellets. For half of the animals, the enriched diet was paired with strawberry flavour and the deficient diet was paired with orange flavour, while the reverse pairings were offered to the others. Lamb preference for the diets was measured daily for the following 15 days. There was a three-way interaction between the high and low vitamin E treatment groups×vitamin E content and type of flavour in the feed×time (days). The lambs preferred pellets flavoured with strawberry but this preference changed to orange flavour in vitamin E-deficient lambs if the orange flavour was paired with high vitamin E. Lambs without a deficiency continued to prefer strawberry-flavoured pellets, regardless of the vitamin E concentrations in the pellets. It is possible that self-learning contributed to the low vitamin E group of lambs changing preference to orange flavour in order to consume more vitamin E, presumably to remediate the deficiency.

  16. Simultaneous determination of 222Rn and 220Rn exhalation rates from building materials used in Central Italy with accumulation chambers and a continuous solid state alpha detector: influence of particle size, humidity and precursors concentration.

    PubMed

    Tuccimei, P; Moroni, M; Norcia, D

    2006-02-01

    A method to determine simultaneously the rates of 222Rn and 220Rn released from building materials quarried in Central Italy is presented. The method makes use of a continuous monitor equipped with a solid state alpha detector, in-line connected to a small accumulation chamber. The effects of chamber leakage and back diffusion on 222Rn free exhalation rate is evaluated. The influence of available exhalation surface, humidity content and precursors concentration on radon and thoron exhalation rates is investigated.

  17. Higher and longer stress-induced increase in dopamine concentrations in the nucleus accumbens of animals predisposed to amphetamine self-administration. A microdialysis study.

    PubMed

    Rougé-Pont, F; Piazza, P V; Kharouby, M; Le Moal, M; Simon, H

    1993-01-29

    Individual vulnerability to the reinforcing effects of drugs appears to be a crucial factor in the development of addiction in humans. In the rat, individuals at risk for psychostimulant self-administration (SA) may be identified from their locomotor reactivity to a stress situation such as exposure to a novel environment. Animals with high locomotor responses to novelty (high responders, HR) acquire amphetamine SA, while animals with low responses (low responders, LR) do not. In this study we examined by microdialysis whether stress-induced extracellular dopamine (DA) concentrations in the nucleus accumbens differed between these two groups of animals. This neurotransmitter was studied because it is thought to be involved in the reinforcing effects of psychostimulants. Furthermore, previous studies have shown that HR animals have a higher basal DOPAC/DA ratio in the nucleus accumbens and higher extracellular concentrations of dopamine in this structure in response to cocaine. The stress procedure used in this experiment consisted of a 10 min tail-pinch. HR animals displayed a higher and longer stress-induced changes in DA concentrations than the LR group. Regression analysis showed that stress-induced changes in DA levels accounted for 75% of the variance observed in the locomotor response to a novel environment. Since higher DA activity in the nucleus accumbens has been reported in animals in which the propensity to psychostimulant SA is induced by brain lesions or life events, this biochemical modification may be one neurobiological substrate of the predisposition to acquire psychostimulant self-administration. PMID:8448654

  18. Increased accumulation of carbohydrates and decreased photosynthetic gene transcript levels in wheat grown at an elevated CO{sub 2} concentration in the field

    SciTech Connect

    Nie, G.; Hendrix, D.L.; Webber, A.N.

    1995-07-01

    Repression of photosynthetic genes by increased soluble carbohydrate concentrations may explain acclimation of photosynthesis to elevated CO{sub 2} concentration. This hypothesis was examined in a field crop of spring wheat (Triticum aestivum L.) grown at both ambient (approximately 360 {mu}mol{sup -1}) and elevated (550 {mu}mol mol{sup -1}) atmospheric CO{sub 2} concentrations using free-air CO{sub 2} enrichment at Maricopa, Arizona. The correspondence of steady-state levels of mRNA transcripts (coding for the 83-kD photosystem 1 apoprotein, sedoheptulose-1,7-bisphosphatase, phosphoribulokinase, phosphoglcerodkinase, and the large and small subunits of ribulose-1,5-bisphosphate carboxylase/oxygenase) with leaf carbohydrate concentrations (glucose-6-phosphate, glucose, fructose, sucrose, fructans, and starch) was examined at different stages of crop and leaf development and through the diurnal cycle. Overall only a weak correspondence between increased soluble carbohydrate concentrations and decreased levels for nuclear gene transcripts was found. The difference in soluble carbohydrate concentration between leaves grown at elevated and current ambient CO{sub 2} concentrations diminished with crop development, whereas the difference in transcript levels increased. In the flag leaf, soluble carbohydrate concentrations declined markedly with the onset of grain filling; yet transcript levels also declined. The results suggest that, many other factors modified its significance in this field wheat crop. 52 refs., 8 figs.

  19. TTX accumulation in pufferfish.

    PubMed

    Noguchi, Tamao; Arakawa, Osamu; Takatani, Tomohiro

    2006-03-01

    Tetrodotoxin (TTX) has been detected in a variety of animals. The finding of TTX in the trumpet shell Charonia sauliae strongly suggested that its origin was its food, a TTX-bearing starfish Astropecten polyacanthus. Since then, the food chain has been consistently implicated as the principal means of TTX intoxication. To identify the primary producer of TTX, intestinal bacteria isolated from several TTX-bearers were investigated for their TTX production. The results demonstrated that some of them could produce TTX. Thus the primary TTX producers in the sea are concluded to be marine bacteria. Subsequently, detritus feeders and zooplankton can be intoxicated with TTX through the food chain, or in conjunction with parasitism or symbiosis. The process followed by small carnivores, omnivores or scavengers, and by organisms higher up the food chain would result in the accumulation of higher concentrations of TTX. Finally, pufferfish at the top of the food chain are intoxicated with TTX. This hypothesis is supported by the fact that net cage and land cultures produce non-toxic pufferfish that can be made toxic by feeding with a TTX-containing diet.

  20. Accumulation of 2,3,7,8-tetrachlorodibenzo-p-dioxin by rainbow trout (Onchorhynchus mykiss) at environmentally relevant dietary concentrations

    USGS Publications Warehouse

    Jones, Paul D.; Kannan, Kurunthachalam; Newsted, John L.; Tillitt, Donald E.; Williams, Lisa L.; Giesy, John P.

    2001-01-01

    Rainbow trout were fed a diet containing 1.8, 18, or 90 pg/g 3H-2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) for up to 320 d. Concentrations of TCDD were determined in muscle, liver, and ovaries at 100, 150, 200, and 250 d. Concentrations of TCDD reached an apparent steady-state concentration in liver after 100 d of exposure, whereas concentrations in other tissues continued to increase until 150 d of exposure. The greatest portion of the total mass of TCDD was present in the muscle tissue with lesser proportions in other organs. As the ovaries developed before spawning, an increase occurred in the total mass of TCDD present in this tissue. The assimilation rate of TCDD during the initial 100 d of the exposure was determined to be between 10 and 30%. This is somewhat less than estimates derived based on both uptake and elimination constants determined during shorter exposures. Biomagnification factors (BMFs) were estimated for all tissues and exposure concentrations, and at all exposure periods. Lipid-normalized BMFs for muscle ranged from 0.38 to 1.51, which is consistent with the value of 1.0 predicted from fugacity theory. Uptake and depuration rate constants were determined and used to predict individual organ TCDD concentrations. Comparison with observed values indicated that the model could be used to predict tissue concentrations from the known concentrations of TCDD in food. This model will allow more refined risk assessments by predicting TCDD concentrations in sensitive tissues such as developing eggs.

  1. Accumulation of pyrethroid compounds in primary cultures of rat cortical neurons

    EPA Science Inventory

    Recent studies have demonstrated that lipophilic compounds (e.g. methylmercury, polychlorinated biphenyls (PCBs) and polybrominated diphenylethers (PBDEs)) rapidly accumulate in cells in culture to concentrations much higher than in the surrounding media. Primary cultures of neur...

  2. [Lead accumulation and elimination in juvenile Acipenser sinensis tissues].

    PubMed

    Feng, Lin; Zhang, Long-Zhen; Zhuang, Ping; Hou, Jun-Li; Zhang, Tao; Liu, Jian; Feng, Guang-Peng

    2010-02-01

    A semi-static test of Pb exposure (0, 0.2, 0.8, and 1.6 mg L(-1)) was carried out to examine the Pb accumulation and elimination in different tissues of juvenile Chinese sturgeon (Acipenser sinensis). With increasing Pb concentration in water, the Pb concentration in juvenile A. sinensis tissues increased, showing a clear dose-response relationship. The Pb accumulation had a trend of being higher in bone (dorsalbone plate and cartilaginous bone) and muscle, followed by in stomach, intestine, and skin, and relatively low in liver, gill, and notochord. A 6-week duration test after Pb exposure showed that in low dose group (0.2 mg x L(-1)), the Pb concentration in all tissues had no significant differences to the control group, but in medium dose group (0.8 mg x L(-1)), the Pb concentration in most tissues except gill stomach, cartilaginous bone, and muscle was significantly higher than the control. In high dose group (1.6 mg x L(-1)), the Pb concentration in the tissues other than liver, intestine and skin was significantly higher than the control. Through the comparison of accumulation and elimination, it was found that after low- and medium dose exposure, the Pb concentration in skin, gill, and liver was higher than its accumulation, presuming that Pb was absorbed from gill, skin, and alimentary canal, and eliminated from gill and skin.

  3. Particulate organic matter higher concentrations, terrestrial sources and losses in bottom waters of the turbidity maximum, Delaware Estuary, U.S.A.

    NASA Astrophysics Data System (ADS)

    Hermes, Anna L.; Sikes, Elisabeth L.

    2016-10-01

    The pathway and fate of land-derived suspended particulate organic matter (POM) as it passes through estuaries remains a poorly constrained component of coastal carbon dynamics. The δ13C of bulk POC (particulate organic carbon; δ13C-POC) and n-alkane biomarkers were used to assess the proportion of algal- and land- (vascular plant) derived POM through the Delaware Estuary, on five cruises in 2010-2011. We found that POC was highly correlated with suspended sediment concentrations (SSC). Higher SSC was present in bottom waters, causing bottom waters to have consistently higher concentrations of POC than surface waters, with the bottom waters of the estuarine turbidity maximum (ETM) exhibiting maximum POC concentrations for all seasons and flow regimes. Algal-derived POM seasonally affected the δ13C-POC and n-alkane geochemical signatures of surface waters, whereas bottom waters were dominated by vascular plant-derived POM. δ13C-POC results suggested a gradual loss in vascular plant-derived POM between the riverine and marine endmember stations. In contrast, n-alkane concentrations peaked in bottom waters of the ETM at 2-5 times surface water concentrations. Indices of the relative proportions of n-alkanes and n-alkanes as a proportion of total POC had their levels decrease considerably downstream of the ETM. These biomarker analyses suggest enhanced loss of land-derived material across the ETM and that the ETM acts as a geochemical filter for vascular plant-derived POM in a classic well mixed estuary.

  4. Tailored sensitivity reduction improves pattern recognition and information recovery with a higher tolerance to varied sample concentration for targeted urinary metabolomics.

    PubMed

    Yan, Zhixiang; Yan, Ru

    2016-04-22

    Variation in total metabolite concentration among different samples has been a major challenge for urinary metabolomics. Here we investigated the potential of tailored sensitivity reduction of high abundance metabolites for improved targeted urinary metabolomics. Two levels of sensitivity reduction of the 21 predominant urinary metabolites were assessed by employing less sensitive transition or collision energy with level 1 (reduced 1) and 2 (reduced 2) exhibiting 30-90% and 2-20% of the optimal sensitivity, respectively. Five postacquisition normalization methods were compared including no normalization, probabilistic quotient normalization, and normalization to sample median, creatinine intensity, and total intensity. Normalization to total intensity with reduced 2 gave the best pattern recognition and information recovery with a higher tolerance to varied sample concentration. Pareto scaling could improve the performance of tailored sensitivity reduction (reduced 2) for targeted urinary metabolomics while data transformation and autoscaling were susceptible to varied sample concentration. Using controlled spike-in experiments, we demonstrated that tailored sensitivity reduction revealed more differentially expressed markers with higher accuracy than did the conventional optimal sensitivity. This was particularly true when the differences between the sample groups are small. This work also served as an introductory guideline for handling targeted metabolomics data using the open-source software MetaboAnalyst.

  5. Arsenic accumulation by edible aquatic macrophytes.

    PubMed

    Falinski, K A; Yost, R S; Sampaga, E; Peard, J

    2014-01-01

    Edible aquatic macrophytes grown in arsenic (As)-contaminated soil and sediment were investigated to determine the extent of As accumulation and potential risk to humans when consumed. Nasturtium officinale (watercress) and Diplazium esculentum (warabi) are two aquatic macrophytes grown and consumed in Hawaii. Neither has been assessed for potential to accumulate As when grown in As-contaminated soil. Some former sugarcane plantation soils in eastern Hawaii have been shown to have concentrations of total As over 500 mg kg(-1). It was hypothesized that both species will accumulate more As in contaminated soils than in non-contaminated soils. N. officinale and D. esculentum were collected in areas with and without As-contaminated soil and sediment. High soil As concentrations averaged 356 mg kg(-1), while low soil As concentrations were 0.75 mg kg(-1). Average N. officinale and D. esculentum total As concentrations were 0.572 mg kg(-1) and 0.075 mg kg(-1), respectively, corresponding to hazard indices of 0.12 and 0.03 for adults. Unlike previous studies where watercress was grown in As-contaminated water, N. officinale did not show properties of a hyperaccumulator, yet plant concentrations in high As areas were more than double those in low As areas. There was a slight correlation between high total As in sediment and soil and total As concentrations in watercress leaves and stems, resulting in a plant uptake factor of 0.010, an order of magnitude higher than previous studies. D. esculentum did not show signs of accumulating As in the edible fiddleheads. Hawaii is unique in having volcanic ash soils with extremely high sorption characteristics of As and P that limit release into groundwater. This study presents a case where soils and sediments were significantly enriched in total As concentration, but the water As concentration was below detection limits.

  6. Accumulate Repeat Accumulate Coded Modulation

    NASA Technical Reports Server (NTRS)

    Abbasfar, Aliazam; Divsalar, Dariush; Yao, Kung

    2004-01-01

    In this paper we propose an innovative coded modulation scheme called 'Accumulate Repeat Accumulate Coded Modulation' (ARA coded modulation). This class of codes can be viewed as serial turbo-like codes, or as a subclass of Low Density Parity Check (LDPC) codes that are combined with high level modulation. Thus at the decoder belief propagation can be used for iterative decoding of ARA coded modulation on a graph, provided a demapper transforms the received in-phase and quadrature samples to reliability of the bits.

  7. Significance of higher drug concentration in erythrocytes of mice infected with Schistosoma japonicum and treated orally with mefloquine at single doses.

    PubMed

    Tao, Yi; Xue, Jian; Jiang, Bin; Zhang, Hao-Bing; Xiao, Shu-Hua

    2015-12-01

    The purpose of the present study is to understand the pharmacokinetic feature of mefloquine measured by erythrocytes and plasma in Schistosoma japonicum (S. j.)-infected mice and non-infected mice after oral administration of the drug at single doses. A high-performance liquid chromatography (HPLC) method was used to measure the plasma and erythrocyte concentrations of mefloquine at varying intervals posttreatment. Our results demonstrated that in non-infected mice treated orally with mefloquine at an ineffective dose of 50 mg/kg or effective dose of 200 mg/kg for 2-72 h, the erythrocyte-to-plasma ratios of mefloquine were 5.8-11.2 or 2-14.2. On the other hand, in S. j.-infected mice treated with the same single doses of the drug, the erythrocyte and plasma drug concentration ratios were 3.1-4.6 or 2.9-8.5, manifesting that either in infected mice or in non-infected mice that received oral mefloquine resulted in higher concentration of mefloquine in erythrocytes than that in plasma. Unexpectedly, under oral administration of mefloquine at a higher single dose of 200 mg/kg, the pharmacokinetic parameter C max values for plasma from S. j.-infected and non-infected mice were 1.6 ± 0.3 and 2.0 ± 0.4 μg/mL, respectively, which were below the determined in vitro LC50 (50 % lethal concentration) value of 4.93 μg/mL. Therefore, the plasma concentration of mefloquine may display a little effect against schistosomes during the treatment. Although the values of T 1/2 and AUC0-∞ for erythrocytes were significantly longer and higher in infected mice than those of corresponding non-infect mice that received the same single mefloqine dose of 50 mg/kg, the C max value was only 2.6 ± 0.4 μg/mL lower than the determined in vitro LC50, which may explain why this low single dose is ineffective against schistosomes in vivo. After administration of higher mefloquine dose of 200 mg/kg, the C max value for erythrocytes in infected mice was 30 % (7.4 ± 0

  8. Higher body weight patients on clopidogrel maintenance therapy have lower active metabolite concentrations, lower levels of platelet inhibition, and higher rates of poor responders than low body weight patients.

    PubMed

    Wagner, Henrik; Angiolillo, Dominick J; Ten Berg, Jurrien M; Bergmeijer, Thomas O; Jakubowski, Joseph A; Small, David S; Moser, Brian A; Zhou, Chunmei; Brown, Patricia; James, Stefan; Winters, Kenneth J; Erlinge, David

    2014-01-01

    Body weight is a predictor of clopidogrel response. However, no prospective studies have compared pharmacodynamic (PD) and pharmacokinetic (PK) data based on body weight. We compared PD and PK effects of clopidogrel 75 mg in low body weight (LBW, <60 kg) and higher body weight (HBW, ≥60 kg) patients with stable coronary artery disease. LBW (n = 34, 56.4 ± 3.7 kg) and HBW (n = 38, 84.7 ± 14.9 kg) aspirin-treated patients received clopidogrel 75 mg for 10-14 days. The area under the concentration-time curve of active metabolite (Clop-AM) calculated through the last quantifiable concentration up to 4 h postdose, AUC(0-tlast), was calculated by noncompartmental methods. Light transmission aggregometry (LTA) (maximum platelet aggregation and inhibition of platelet aggregation to 20 μM adenosine diphosphate (ADP), and residual platelet aggregation to 5 μM ADP), VerifyNow(®) P2Y12 reaction units (PRU), and vasodilator-associated stimulated phosphoprotein phosphorylation platelet reactivity index (VASP-PRI) were performed. Mean AUC(0-tlast) was lower in HBW than LBW patients: 12.8 versus 17.9 ng h/mL. HBW patients had higher platelet reactivity as measured by LTA (all p ≤ 0.01), PRU (207 ± 68 vs. 152 ± 57, p < 0.001), and VASP-PRI (56 ± 18 vs. 39 ± 17, p < 0.001). More HBW patients exhibited high on-treatment platelet reactivity (HPR) using PRU (35 vs. 9%) and VASP-PRI (65 vs. 27%). Body weight correlated with PRU and VASP-PRI (both p < 0.001), and inversely with log transformed AUC(0-tlast) (p < 0.001). In conclusion, HBW patients had lower levels of Clop-AM, and higher platelet reactivity and rates of HPR than LBW subjects, contributing to their suboptimal response to clopidogrel. PMID:24043374

  9. Metals and metalloids in fruits of tomatoes (Solanum lycopersicum) and their cultivation soils in the Basque Country: concentrations and accumulation trends.

    PubMed

    Rodriguez-Iruretagoiena, Azibar; Trebolazabala, Josu; Martinez-Arkarazo, Irantzu; de Diego, Alberto; Madariaga, Juan Manuel

    2015-04-15

    The concentrations of several elements (Al, Fe, As, Cu, Cd, Co, Cr, Mn, Ni, Pb, Sn, V, and Zn) were measured in soils and the edible part of different vegetables (tomatoes (Solanum lycopersicum "Raf") peppers (Capsicum annuum), chards (Betavulgaris var. cicla), artichokes (Cynarascholymus)) and fruits (Raspberries (Rubusidaeus)) from 13 orchards in the Basque Country affected by different pollution sources. Multivariate analysis of data was used to look for possible correlations between metals in soil and metals in the edible part of the plant. Only manganese showed a correlation significantly different from zero. The metal concentrations found in the edible part were always below the upper limits recommended by the European legislation in force. The Bioaccumulation Index was used to investigate how efficient the plant is to uptake an element from the cultivation soil and to preserve its edible part from the element. PMID:25466128

  10. Metals and metalloids in fruits of tomatoes (Solanum lycopersicum) and their cultivation soils in the Basque Country: concentrations and accumulation trends.

    PubMed

    Rodriguez-Iruretagoiena, Azibar; Trebolazabala, Josu; Martinez-Arkarazo, Irantzu; de Diego, Alberto; Madariaga, Juan Manuel

    2015-04-15

    The concentrations of several elements (Al, Fe, As, Cu, Cd, Co, Cr, Mn, Ni, Pb, Sn, V, and Zn) were measured in soils and the edible part of different vegetables (tomatoes (Solanum lycopersicum "Raf") peppers (Capsicum annuum), chards (Betavulgaris var. cicla), artichokes (Cynarascholymus)) and fruits (Raspberries (Rubusidaeus)) from 13 orchards in the Basque Country affected by different pollution sources. Multivariate analysis of data was used to look for possible correlations between metals in soil and metals in the edible part of the plant. Only manganese showed a correlation significantly different from zero. The metal concentrations found in the edible part were always below the upper limits recommended by the European legislation in force. The Bioaccumulation Index was used to investigate how efficient the plant is to uptake an element from the cultivation soil and to preserve its edible part from the element.

  11. Root and shoot gas exchange respond additively to moderate ozone and methyl jasmonate without induction of ethylene: ethylene is induced at higher O3 concentrations

    PubMed Central

    Grantz, D.A.; Vu, H.-B.

    2012-01-01

    The available literature is conflicting on the potential protection of plants against ozone (O3) injury by exogenous jasmonates, including methyl jasmonate (MeJA). Protective antagonistic interactions of O3 and MeJA have been observed in some systems and purely additive effects in others. Here it is shown that chronic exposure to low to moderate O3 concentrations (4–114 ppb; 12 h mean) and to MeJA induced additive reductions in carbon assimilation (A n) and root respiration (R r), and in calculated whole plant carbon balance. Neither this chronic O3 regime nor MeJA induced emission of ethylene (ET) from the youngest fully expanded leaves. ET emission was induced by acute 3 h pulse exposure to much higher O3 concentrations (685 ppb). ET emission was further enhanced in plants treated with MeJA. Responses of growth, allocation, photosynthesis, and respiration to moderate O3 concentrations and to MeJA appear to be independent and additive, and not associated with emission of ET. These results suggest that responses of Pima cotton to environmentally relevant O3 are not mediated by signalling pathways associated with ET and MeJA, though these pathways are inducible in this species and exhibit a synergistic O3×MeJA interaction at very high O3 concentrations. PMID:22563119

  12. Impacts of Stabilized Criegee Intermediates, surface uptake processes and higher aromatic secondary organic aerosol yields on predicted PM2.5 concentrations in the Mexico City Metropolitan Zone

    NASA Astrophysics Data System (ADS)

    Ying, Qi; Cureño, Iris V.; Chen, Gang; Ali, Sajjad; Zhang, Hongliang; Malloy, Meagan; Bravo, Humberto A.; Sosa, Rodolfo

    2014-09-01

    The Community Multiscale Air Quality Model (CMAQ) with the SAPRC-99 gas phase photochemical mechanism and the AERO5 aerosol module was applied to model gases and particulate matter (PM) concentrations in the Mexico City Metropolitan Zone (MCMZ) and the surrounding regions for March 2006 using the official 2006 emission inventories, along with emissions from biogenic sources, biomass burning, windblown dust, the Tula Industrial Complex and the Popocatépetl volcano. The base case model was capable of reproducing the observed hourly concentrations of O3 and attaining CO, NO2 and NOx performance similar to previous modeling studies. Although the base case model performance of hourly PM2.5 and PM10 meets the model performance criteria, under-prediction of high PM2.5 concentrations in late morning indicates that secondary PM, such as sulfate and secondary organic aerosol (SOA), might be under-predicted. Several potential pathways to increase SOA and secondary sulfate were investigated, including Stabilized Criegee Intermediates (SCIs) from ozonolysis reactions of unsaturated hydrocarbons and their reactions with SO2, the reactive uptake processes of SO2, glyoxal and methylglyoxal on particle surface and higher SOA formation due to higher mass yields of aromatic SOA precursors. Averaging over the entire episode, the glyoxal and methylglyoxal reactive uptake and higher aromatics SOA yields contribute to ∼0.9 μg m-3 and ∼1.25 μg m-3 of SOA, respectively. Episode average SOA in the MCMZ reaches ∼3 μg m-3. The SCI pathway increases PM2.5 sulfate by 0.2-0.4 μg m-3 or approximately 10-15%. The relative amount of sulfate increase due to SCI agrees with previous studies in summer eastern US. Surface SO2 uptake significantly increases sulfate concentration in MCMZ by 1-3 μg m-3 or approximately 50-60%. The higher SOA and sulfate leads to improved PM2.5 and PM10 model performance.

  13. Higher concentrations of nanoscale zero-valent iron (nZVI) in soil induced rice chlorosis due to inhibited active iron transportation.

    PubMed

    Wang, Jie; Fang, Zhanqiang; Cheng, Wen; Yan, Xiaomin; Tsang, Pokeung Eric; Zhao, Dongye

    2016-03-01

    In this study, the effects of concentrations 0, 100, 250, 500, 750 and 1000 mg kg(-1) of nanoscale zero-valent iron (nZVI) on germination, seedlings growth, physiology and toxicity mechanisms were investigated. The results showed that nZVI had no effect on germination, but inhibited the rice seedlings growth in higher concentrations (>500 mg kg(-1) nZVI). The highest suppression rate of the length of roots and shoots reached 46.9% and 57.5%, respectively. The 1000mg kg(-1) nZVI caused the highest suppression rates for chlorophyll and carotenoids, at 91.6% and 85.2%, respectively. In addition, the activity of antioxidant enzymes was altered by the translocation of nanoparticles and changes in active iron content. Visible symptoms of iron deficiency were observed at higher concentrations, at which the active iron content decreased 61.02% in the shoots, but the active iron content not decreased in roots. Interestingly, the total and available amounts of iron in the soil were not less than those in the control. Therefore, the plants iron deficiency was not caused by (i) deficiency of available iron in the soil and (ii) restraint of the absorption that plant takes in the available iron, while induced by (ⅲ) the transport of active iron from the root to the shoot was blocked. The cortex tissues were seriously damaged by nZVI which was transported from soil to the root, these were proved by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS). This current study shows that the mechanism of iron deficiency in rice seedling was due to transport of active iron from the root to the shoot blocked, which was caused by the uptake of nZVI.

  14. Higher serum carotenoid concentrations associated with a lower prevalence of the metabolic syndrome in middle-aged and elderly Chinese adults.

    PubMed

    Liu, Jun; Shi, Wen-Qi; Cao, Yi; He, Li-Ping; Guan, Ke; Ling, Wen-Hua; Chen, Yu-Ming

    2014-12-28

    The association between serum carotenoids and the metabolic syndrome (MetS) remains uncertain, and little is known about this relationship in the Chinese population. The present study examined the association between serum carotenoid concentrations and the MetS in Chinese adults. We conducted a community-based cross-sectional study in which 2148 subjects (1547 women and 601 men) aged 50-75 years were recruited in urban Guangzhou, China. Dietary data and other covariates were collected during face-to-face interviews. Blood pressure, waist circumference, blood lipids, glucose and serum carotenoids (α-, β-carotene, β-cryptoxanthin, lycopene and lutein/zeaxanthin) were examined. We found dose-response inverse relationships between individual serum carotenoid concentrations and total carotenoids and the prevalence of the MetS after adjusting for potential confounders (P for trend < 0.001). The OR of the MetS for the highest (v. lowest) quartile were 0.31 (95% CI 0.20, 0.47) for α-carotene, 0.23 (95% CI 0.15, 0.36) for β-carotene, 0.44 (95% CI 0.29, 0.67) for β-cryptoxanthin, 0.39 (95% CI 0.26, 0.58) for lycopene, 0.28 (95% CI 0.18, 0.44) for lutein+zeaxanthin and 0.19 (95% CI 0.12, 0.30) for total carotenoids. Higher concentrations of each individual carotenoid and total carotenoids were significantly associated with a decrease in the number of abnormal MetS components (P for trend < 0.001-0.023). Higher serum carotenoid levels were associated with a lower prevalence of the MetS and fewer abnormal MetS components in middle-aged and elderly Chinese adults. PMID:25345663

  15. Higher concentrations of nanoscale zero-valent iron (nZVI) in soil induced rice chlorosis due to inhibited active iron transportation.

    PubMed

    Wang, Jie; Fang, Zhanqiang; Cheng, Wen; Yan, Xiaomin; Tsang, Pokeung Eric; Zhao, Dongye

    2016-03-01

    In this study, the effects of concentrations 0, 100, 250, 500, 750 and 1000 mg kg(-1) of nanoscale zero-valent iron (nZVI) on germination, seedlings growth, physiology and toxicity mechanisms were investigated. The results showed that nZVI had no effect on germination, but inhibited the rice seedlings growth in higher concentrations (>500 mg kg(-1) nZVI). The highest suppression rate of the length of roots and shoots reached 46.9% and 57.5%, respectively. The 1000mg kg(-1) nZVI caused the highest suppression rates for chlorophyll and carotenoids, at 91.6% and 85.2%, respectively. In addition, the activity of antioxidant enzymes was altered by the translocation of nanoparticles and changes in active iron content. Visible symptoms of iron deficiency were observed at higher concentrations, at which the active iron content decreased 61.02% in the shoots, but the active iron content not decreased in roots. Interestingly, the total and available amounts of iron in the soil were not less than those in the control. Therefore, the plants iron deficiency was not caused by (i) deficiency of available iron in the soil and (ii) restraint of the absorption that plant takes in the available iron, while induced by (ⅲ) the transport of active iron from the root to the shoot was blocked. The cortex tissues were seriously damaged by nZVI which was transported from soil to the root, these were proved by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS). This current study shows that the mechanism of iron deficiency in rice seedling was due to transport of active iron from the root to the shoot blocked, which was caused by the uptake of nZVI. PMID:26803790

  16. Heat accumulator

    SciTech Connect

    Bracht, A.

    1981-09-29

    A heat accumulator comprises a thermally-insulated reservoir full of paraffin wax mixture or other flowable or meltable heat storage mass, heat-exchangers immersed in the mass, a heat-trap connected to one of the heat-exchangers, and a heat user connected to the other heat-exchanger. Pumps circulate fluids through the heat-trap and the heat-using means and the respective heat-exchangers, and a stirrer agitates and circulates the mass, and the pumps and the stirrer and electric motors driving these devices are all immersed in the mass.

  17. Higher maternal serum concentrations of nicotinamide and related metabolites in late pregnancy are associated with a lower risk of offspring atopic eczema at age 12 months

    PubMed Central

    El-Heis, S; Crozier, SR; Robinson, SM; Harvey, NC; Cooper, C; Inskip, HM; Godfrey, KM

    2016-01-01

    Background Evidence that atopic eczema partly originates in utero is increasing, with some studies linking the risk of developing the condition with aspects of maternal diet during pregnancy. Nicotinamide, a naturally occurring nutrient that is maintained through the dietary intakes of vitamin B3 and tryptophan has been used in the treatment of some skin conditions including atopic eczema. Objective To examine the relation of maternal serum concentrations of nicotinamide and related tryptophan metabolites to the risk of atopic eczema in the offspring. Methods Within the UK Southampton Women Survey, infantile atopic eczema at ages 6 and 12 months was ascertained (modified UK Working Party Criteria for the Definition of Atopic Dermatitis). Maternal serum levels of kynurenine, kynurenic acid, anthranilic acid, tryptophan, nicotinamide and N1-methylnicotinamide were measured in late pregnancy by mass spectrometry, n=497 and related to the odds ratio of infantile atopic eczema. Results Maternal nicotinamide and related metabolite concentrations were not associated with offspring atopic eczema at age 6 months. Higher concentrations of nicotinamide and anthranilic acid were, however, associated with a lower risk of eczema at age 12 months (odds ratios 0.69, 95% CI 0.53-0.91 /SD change, p=0.007 and 0.63, 0.48-0.83, p=0.001, respectively). The associations were robust to adjustment for potentially confounding variables. Conclusion and clinical relevance This is the first study linking maternal serum concentrations of nicotinamide and related metabolites to the risk of atopic eczema in the offspring. The findings point to potentially modifiable maternal influences on this complex and highly prevalent condition. PMID:27517618

  18. Contributions of apoplasmic cadmium accumulation, antioxidative enzymes and induction of phytochelatins in cadmium tolerance of the cadmium-accumulating cultivar of black oat (Avena strigosa Schreb.).

    PubMed

    Uraguchi, Shimpei; Kiyono, Masako; Sakamoto, Takuya; Watanabe, Izumi; Kuno, Katsuji

    2009-07-01

    The contributions of cadmium (Cd) accumulation in cell walls, antioxidative enzymes and induction of phytochelatins (PCs) to Cd tolerance were investigated in two distinctive genotypes of black oat (Avena strigosa Schreb.). One cultivar of black oat 'New oat' accumulated Cd in the leaves at the highest concentration compared to another black oat cultivar 'Soil saver' and other major graminaceous crops. The shoot:root Cd ratio also demonstrated that 'New oat' was the high Cd-accumulating cultivar, whereas 'Soil saver' was the low Cd-accumulating cultivar. Varied levels of Cd exposure demonstrated the strong Cd tolerance of 'New oat'. By contrast, low Cd-accumulating cultivar 'Soil saver' suffered Cd toxicity such as growth defects and increased lipid peroxidation, even though it accumulated less Cd in shoots than 'New oat'. Higher activities of ascorbate peroxidase (EC 1.11.1.11) and superoxide dismutase (EC 1. 15. 1. 1) were observed in the leaves of 'New oat' than in 'Soil saver'. No advantage of 'New oat' in PCs induction was observed in comparison to Cd-sensitive cultivar 'Soil saver', although Cd exposure increased the concentration of total PCs in both cultivars. Higher and increased Cd accumulation in cell wall fraction was observed in shoots of 'New oat'. On the other hand, in 'Soil saver', apoplasmic Cd accumulation showed saturation under higher Cd exposure. Overall, the present results suggest that cell wall Cd accumulation and antioxidative activities function in the tolerance against Cd stress possibly in combination with vacuolar Cd compartmentation.

  19. Different levels in orexin concentrations and risk factors associated with higher orexin levels: comparison between detoxified opiate and methamphetamine addicts in 5 Chinese cities.

    PubMed

    Zhang, Haoran; Lian, Zhi; Yan, Shiyan; Bao, Yanping; Liu, Zhimin

    2013-01-01

    This study sought to explore the degree of orexin levels in Chinese opiate and methamphetamine addicts and the differences between them. The cross-sectional study was conducted among detoxified drug addicts from Mandatory Detoxification Center (MDC) in five Chinese cities. Orexin levels were assayed with radioimmunoassay (RIA). Mann-Whitney U test and Kruskal-Wallis test were used to detect differences across groups, and logistic regression was used to explore the association between orexin levels and characteristics of demographic and drug abuse. Between November 2009 and January 2011, 285 opiates addicts, 112 methamphetamine addicts, and 79 healthy controls were enrolled. At drug withdrawal period, both opiate and methamphetamine addicts had lower median orexin levels than controls, and median orexin levels in opiate addicts were higher than those in methamphetamine addicts (all above P < 0.05). Adjusted odds of the above median concentration of orexin were higher for injection than "chasing the dragon" (AOR = 3.1, 95% CI = 1.2-7.9). No significant factors associated with orexin levels of methamphetamine addicts were found. Development of intervention method on orexin system by different administration routes especially for injected opiate addicts at detoxification phase may be significant and was welcome. PMID:24102051

  20. Plastic accumulation in the Mediterranean sea.

    PubMed

    Cózar, Andrés; Sanz-Martín, Marina; Martí, Elisa; González-Gordillo, J Ignacio; Ubeda, Bárbara; Gálvez, José Á; Irigoien, Xabier; Duarte, Carlos M

    2015-01-01

    Concentrations of floating plastic were measured throughout the Mediterranean Sea to assess whether this basin can be regarded as a great accumulation region of plastic debris. We found that the average density of plastic (1 item per 4 m2), as well as its frequency of occurrence (100% of the sites sampled), are comparable to the accumulation zones described for the five subtropical ocean gyres. Plastic debris in the Mediterranean surface waters was dominated by millimeter-sized fragments, but showed a higher proportion of large plastic objects than that present in oceanic gyres, reflecting the closer connection with pollution sources. The accumulation of floating plastic in the Mediterranean Sea (between 1,000 and 3,000 tons) is likely related to the high human pressure together with the hydrodynamics of this semi-enclosed basin, with outflow mainly occurring through a deep water layer. Given the biological richness and concentration of economic activities in the Mediterranean Sea, the affects of plastic pollution on marine and human life are expected to be particularly frequent in this plastic accumulation region.

  1. Plastic Accumulation in the Mediterranean Sea

    PubMed Central

    Cózar, Andrés; Sanz-Martín, Marina; Martí, Elisa; González-Gordillo, J. Ignacio; Ubeda, Bárbara; Gálvez, José Á.; Irigoien, Xabier; Duarte, Carlos M.

    2015-01-01

    Concentrations of floating plastic were measured throughout the Mediterranean Sea to assess whether this basin can be regarded as a great accumulation region of plastic debris. We found that the average density of plastic (1 item per 4 m2), as well as its frequency of occurrence (100% of the sites sampled), are comparable to the accumulation zones described for the five subtropical ocean gyres. Plastic debris in the Mediterranean surface waters was dominated by millimeter-sized fragments, but showed a higher proportion of large plastic objects than that present in oceanic gyres, reflecting the closer connection with pollution sources. The accumulation of floating plastic in the Mediterranean Sea (between 1,000 and 3,000 tons) is likely related to the high human pressure together with the hydrodynamics of this semi-enclosed basin, with outflow mainly occurring through a deep water layer. Given the biological richness and concentration of economic activities in the Mediterranean Sea, the affects of plastic pollution on marine and human life are expected to be particularly frequent in this plastic accumulation region. PMID:25831129

  2. Higher Education or Higher Skilling?

    ERIC Educational Resources Information Center

    Muller, Steven

    1974-01-01

    Higher education may return to education for a minority, an unlikely course; concentrate on higher skilling, the road we are on today; or restore general education, the most attractive possibility, which can be implemented by restoring basic education in literacy, history, human biology, and language. (JH)

  3. Higher Urinary Bisphenol A Concentration Is Associated with Unexplained Recurrent Miscarriage Risk: Evidence from a Case-Control Study in Eastern China

    PubMed Central

    Shen, Yueping; Zheng, Yanmin; Jiang, Jingting; Liu, Yinmei; Luo, Xiaoming; Shen, Zongji; Chen, Xin; Wang, Yan; Dai, Yiheng; Zhao, Jing; Liang, Hong; Chen, Aimin; Yuan, Wei

    2015-01-01

    Background Evidence about the association between Bisphenol A (BPA) and the risk of recurrent miscarriage (RM) in human being is still limited. Objective We evaluated the association of urinary BPA concentrations with RM in human being. Methods A hospital-based 1:2 matched case-control study on RM was carried out in Suzhou and Kunshan in Jiangsu Province in China between August 2008 and November 2011. Total urinary BPA concentrations in 264 eligible urine samples (102 RM patients and 162 controls) were measured using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The Wilcoxon test and conditional logistic regression were used to estimate the differences between the groups and odds ratios (OR) with 95% confidence intervals (CI), respectively. Results The median ± IQR (interquartile range) (P75-P25) values of non-creatinine-adjusted total urinary BPA levels in the RM patients and the controls were 1.66±3.69ng/ml and 0.58±1.07ng/ml, respectively (0.98±2.67μg/g Cr (creatinine) and 0.40±0.77μg/g Cr. The adjusted BPA level was significantly higher in the RM patients than in the controls (Wilcoxon test, Z = 4.476, P<0.001). Higher level of urinary BPA was significantly associated with an increased risk of RM (P-trend <0.001). Compared to the groups with urinary BPA levels less than 0.16μg/g Cr, the women with levels of 0.40–0.93μg/g Cr and 0.93μg/g Cr or above had a significantly higher risk of RM (OR = 3.91, 95%CI: 1.23–12.45 and OR = 9.34, 95%CI: 3.06–28.44) that persisted after adjusting for confounding factors. The time from recently RM date to recruitment does not significantly influence the urinary BPA level (P = 0.090). Conclusion Exposure to BPA may be associated with RM risk. PMID:26011304

  4. Accumulation of heavy metals using Sorghum sp.

    PubMed

    Soudek, Petr; Petrová, Šarka; Vaňková, Radomíra; Song, Jing; Vaněk, Tomaš

    2014-06-01

    The essential requirement for the effective phytoremediation is selection of a plant species which should be metal tolerant, with high biomass production and known agronomic techniques. The above mentioned criteria are met by crop plant sorghum (Sorghum bicolor). The response of hydroponically grown S. bicolor plants to cadmium and zinc stress was followed. The impact of metal application on physiological parameters, including changes in chlorophylls contents and antioxidative enzymes activities, was followed during the stress progression. Cadmium and zinc were accumulated primarily in the roots of sorghum plants. However, elevation of metal concentrations in the media promoted their transfer to the shoots. Toxic effects of metals applied at lower concentrations were less serious in the shoots in comparison with their influence to the roots. When applied at higher concentrations, transfer of the metals into the leaves increased, causing growth reduction and leading to Chl loss and metal-induced chlorosis. Moreover, higher metal levels in the roots overcame the quenching capacity of peroxidase and glutathione transferase, which was associated with reduction of their activities. Fortification of antioxidant system by addition of glutathione significantly increased the accumulation of cadmium in the roots as well as in the shoots at the highest cadmium concentration applied.

  5. Accumulation of persistent organic pollutants in parasites.

    PubMed

    Yen Le, T T; Rijsdijk, Laurie; Sures, Bern; Hendriks, A Jan

    2014-08-01

    Organisms are simultaneously exposed to various stressors, including parasites and pollutants, that may interact with each other. Research on the accumulation of organic compounds in host-parasite systems is scant compared to studies on parasite-metal interactions and mainly focuses on intestinal endoparasites. We reviewed factors that determine the accumulation of persistent organic pollutants (POPs) in host-parasite systems. The wet/dry weight-based concentration of POPs in these parasites is usually lower than that in host tissues because of lower lipid contents in the parasites. However, the fractionation of the pollutants into parasites and their hosts may vary, depending on developmental stages in the life cycle of the parasites. Developmental stages determine the trophic relationship and the taxon of the parasite in the host-parasite systems because of different feeding strategies between the stages. Lipid-corrected concentrations of organic chemicals in the host are usually higher than those in the endoparasites studied. This phenomenon is attributed to a number of physiological and behavioural processes, such as feeding selectivity and strategy and excretion. Moreover, no significant relationship was found between the accumulation factor (i.e. the ratio between the lipid-corrected concentrations in parasites and in their hosts) for polychlorinated biphenyls and either hydrophobicity or molecular size. At the intermediate hydrophobicity, larger and more lipophilic compounds are accumulated at higher levels in both parasites and the host than smaller and less lipophilic compounds. The bioaccumulation of POPs in parasites is affected by some other abiotic, e.g. temperature, and biotic factors, e.g. the number of host species infected by parasites.

  6. Higher Surface Ozone Concentrations Over the Chesapeake Bay than Over the Adjacent Land: Observations and Models from the DISCOVER-AQ and CBODAQ Campaigns

    NASA Technical Reports Server (NTRS)

    Goldberg, Daniel L.; Loughner, Christopher P.; Tzortziou, Maria; Stehr, Jeffrey W.; Pickering, Kenneth E.; Marufu, Lackson T.; Dickerson, Russell R.

    2013-01-01

    Air quality models, such as the Community Multiscale Air Quality (CMAQ) model, indicate decidedly higher ozone near the surface of large interior water bodies, such as the Great Lakes and Chesapeake Bay. In order to test the validity of the model output, we performed surface measurements of ozone (O3) and total reactive nitrogen (NOy) on the 26-m Delaware II NOAA Small Research Vessel experimental (SRVx), deployed in the Chesapeake Bay for 10 daytime cruises in July 2011 as part of NASA's GEO-CAPE CBODAQ oceanographic field campaign in conjunction with NASA's DISCOVER-AQ air quality field campaign. During this 10-day period, the EPA O3 regulatory standard of 75 ppbv averaged over an 8-h period was exceeded four times over water while ground stations in the area only exceeded the standard at most twice. This suggests that on days when the Baltimore/Washington region is in compliance with the EPA standard, air quality over the Chesapeake Bay might exceed the EPA standard. Ozone observations over the bay during the afternoon were consistently 10-20% higher than the closest upwind ground sites during the 10-day campaign; this pattern persisted during good and poor air quality days. A lower boundary layer, reduced cloud cover, slower dry deposition rates, and other lesser mechanisms, contribute to the local maximum of ozone over the Chesapeake Bay. Observations from this campaign were compared to a CMAQ simulation at 1.33 km resolution. The model is able to predict the regional maximum of ozone over the Chesapeake Bay accurately, but NOy concentrations are significantly overestimated. Explanations for the overestimation of NOy in the model simulations are also explored

  7. Higher surface ozone concentrations over the Chesapeake Bay than over the adjacent land: Observations and models from the DISCOVER-AQ and CBODAQ campaigns

    NASA Astrophysics Data System (ADS)

    Goldberg, Daniel L.; Loughner, Christopher P.; Tzortziou, Maria; Stehr, Jeffrey W.; Pickering, Kenneth E.; Marufu, Lackson T.; Dickerson, Russell R.

    2014-02-01

    Air quality models, such as the Community Multiscale Air Quality (CMAQ) model, indicate decidedly higher ozone near the surface of large interior water bodies, such as the Great Lakes and Chesapeake Bay. In order to test the validity of the model output, we performed surface measurements of ozone (O3) and total reactive nitrogen (NOy) on the 26-m Delaware II NOAA Small Research Vessel experimental (SRVx), deployed in the Chesapeake Bay for 10 daytime cruises in July 2011 as part of NASA's GEO-CAPE CBODAQ oceanographic field campaign in conjunction with NASA's DISCOVER-AQ air quality field campaign. During this 10-day period, the EPA O3 regulatory standard of 75 ppbv averaged over an 8-h period was exceeded four times over water while ground stations in the area only exceeded the standard at most twice. This suggests that on days when the Baltimore/Washington region is in compliance with the EPA standard, air quality over the Chesapeake Bay might exceed the EPA standard. Ozone observations over the bay during the afternoon were consistently 10-20% higher than the closest upwind ground sites during the 10-day campaign; this pattern persisted during good and poor air quality days. A lower boundary layer, reduced cloud cover, slower dry deposition rates, and other lesser mechanisms, contribute to the local maximum of ozone over the Chesapeake Bay. Observations from this campaign were compared to a CMAQ simulation at 1.33 km resolution. The model is able to predict the regional maximum of ozone over the Chesapeake Bay accurately, but NOy concentrations are significantly overestimated. Explanations for the overestimation of NOy in the model simulations are also explored.

  8. Higher urinary heavy metal, phthalate, and arsenic but not parabens concentrations in people with high blood pressure, U.S. NHANES, 2011-2012.

    PubMed

    Shiue, Ivy

    2014-06-01

    Link between environmental chemicals and human health has emerged but not been completely examined in risk factors. Therefore, it was aimed to study the relationships of different sets of urinary environmental chemical concentrations and risk of high blood pressure (BP) in a national, population-based study. Data were retrieved from United States National Health and Nutrition Examination Surveys, 2011-2012 including demographics, BP readings, and urinary environmental chemical concentrations. Analyses included chi-square test, t-test and survey-weighted logistic regression modeling. After full adjustment (adjusting for urinary creatinine, age, sex, ethnicity, and body mass index), urinary cesium (OR 1.56, 95%CI 1.11-2.20, P = 0.014), molybden (OR 1.46, 95%CI 1.06-2.01, P = 0.023), manganese (OR 1.42, 95%CI 1.09-1.86, P = 0.012), lead (OR 1.58, 95%CI 1.28-1.96, P < 0.001), tin (OR 1.44, 95%CI 1.25-1.66, P < 0.001), antimony (OR 1.39, 95%CI 1.10-1.77, P = 0.010), and tungsten (OR 1.49, 95%CI 1.25-1.77, P < 0.001) concentrations were observed to be associated with high BP. People with higher urinary mono-2-ethyl-5-carboxypentyl phthalate (OR 1.33, 95%CI 1.00-1.62, P = 0.006), mono-n-butyl phthalate (OR 1.35, 95%CI 1.13-1.62, P = 0.002), mono-2-ethyl-5-hydroxyhexyl (OR 1.25, 95%CI 1.05-1.49, P = 0.014), mono-n-methyl phthalate (OR 1.26, 95%CI 1.07-1.48, P = 0.007), mono-2-ethyl-5-oxohexyl (OR 1.25, 95%CI 1.07-1.48, P = 0.009), and monobenzyl phthalate (OR 1.40, 95%CI 1.15-1.69, P = 0.002) tended to have high BP as well. However, there are no clear associations between environmental parabens and high BP, nor between pesticides and high BP. In addition, trimethylarsine oxide (OR 2.47, 95%CI 1.27-4.81, P = 0.011) and dimethylarsonic acid concentrations (OR 1.42, 95%CI 1.12-1.79, P = 0.006) were seen to be associated with high BP. In sum, urinary heavy metal, phthalate, and arsenic concentrations were associated with high BP, although the causal effect cannot be

  9. Mercury accumulation in bats near hydroelectric reservoirs in Peninsular Malaysia.

    PubMed

    Syaripuddin, Khairunnisa; Kumar, Anjali; Sing, Kong-Wah; Halim, Muhammad-Rasul Abdullah; Nursyereen, Muhammad-Nasir; Wilson, John-James

    2014-09-01

    In large man-made reservoirs such as those resulting from hydroelectric dam construction, bacteria transform the relatively harmless inorganic mercury naturally present in soil and the submerged plant matter into toxic methylmercury. Methylmercury then enters food webs and can accumulate in organisms at higher trophic levels. Bats feeding on insects emerging from aquatic systems can show accumulation of mercury consumed through their insect prey. In this study, we investigated whether the concentration of mercury in the fur of insectivorous bat species was significantly higher than that in the fur of frugivorous bat species, sampled near hydroelectric reservoirs in Peninsular Malaysia. Bats were sampled at Temenggor Lake and Kenyir Lake and fur samples from the most abundant genera of the two feeding guilds-insectivorous (Hipposideros and Rhinolophus) and frugivorous (Cynopterus and Megaerops) were collected for mercury analysis. We found significantly higher concentrations of total mercury in the fur of insectivorous bats. Mercury concentrations also differed significantly between insectivorous bats sampled at the two sites, with bats from Kenyir Lake, the younger reservoir, showing higher mercury concentrations, and between the insectivorous genera, with Hipposideros bats showing higher mercury concentrations. Ten bats (H. cf. larvatus) sampled at Kenyir Lake had mercury concentrations approaching or exceeding 10 mg/kg, which is the threshold at which detrimental effects occur in humans, bats and mice. PMID:24840106

  10. Cadmium uptake and speciation changes in the rhizosphere of cadmium accumulator and non-accumulator oilseed rape varieties.

    PubMed

    Su, Dechun; Xing, Jianping; Jiao, Weiping; Wong, Woonchung

    2009-01-01

    Characteristics of cadmium (Cd) uptake kinetics and distribution of Cd speciation in the rhizosphere for Cd accumulator and non-accumulator oilseed rape varieties were investigated under nutrient solution and rhizobox soil culture conditions. The results showed that the maximal influx (V(max)) for Cd2+ and Km were significantly different for the two oilseed rape varieties. The value of V(max) for Cd accumulator oilseed rape Zhucang Huazi was two-fold greater than that for oilseed rape Chuan you II-93. The exchangeable Cd concentration in the rhizosphere was significantly lower than in non-rhizospheric soils supplemented with CdSO4 for both the varieties. Carbonate-bound Cd in the rhizosphere of Cd accumulator oilseed rape was significantly higher than that in the rhizosphere of non-accumulator oilseed rape and non-rhizospheric soil. Cd accumulator oilseed rape had a higher Cd2+ affinity and more ability to uptake insoluble Cd in the soil than the non-accumulator oilseed rape.

  11. Edaphic factors affecting the toxicity and accumulation of arsenate in the earthworm Lumbricus terrestris

    SciTech Connect

    Meharg, A.A.; Shore, R.F.; Broadgate, K.

    1998-06-01

    The toxicity and accumulation of arsenate was determined in the earthworm Lumbricus terrestris in soil from different layers of a forest profile. Toxicity increased fourfold between 2 and 10 d. Edaphic factors (pH, soil organic matter, and depth in soil profile) also affected toxicity with a three fold decrease in the concentration that causes 50% mortality with increasing depth in soil. In a 4-d exposure study, there was no evidence of arsenic bioconcentration in earthworm tissue, although bioaccumulation was occurring. There was a considerable difference in tissue residues between living and dead earthworms, with dead worms having higher concentrations. This difference was dependent on both soil arsenate concentration and on soil type. Over a wide range of soil arsenate concentrations, earthworm arsenic residues are homeostatically maintained in living worms, but this homeostasis breaks down during death. Alternatively, equilibration with soil residues may occur via accumulation after death. In long-term accumulation studies in soils dosed with a sublethal arsenate concentration, bioconcentration of arsenate did not occur until day 12, after which earthworm concentrations rose steadily above the soil concentration, with residues in worms three fold higher than soil concentrations by the termination of the study. This bioconcentration only occurred in depurated worms over the time period of the study. Initially, depurated worms had lower arsenic concentrations than undepurated until tissue concentrations were equivalent to the soil concentration. Once tissue concentration was greater than soil concentration, depurated worms had higher arsenic residues than undepurated.

  12. Survival strategies of polyphosphate accumulating organisms and glycogen accumulating organisms under conditions of low organic loading.

    PubMed

    Carvalheira, Mónica; Oehmen, Adrian; Carvalho, Gilda; Reis, Maria A M

    2014-11-01

    Enhanced biological phosphorus removal (EBPR) is usually limited by organic carbon availability in wastewater treatment plants (WWTPs). Polyphosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs) were operated under extended periods with low organic carbon loading in order to examine its impact on their activity and survival. The decrease in organic carbon load affected PAOs and GAOs in different ways, where the biomass decay rate of GAOs was approximately 4times higher than PAOs. PAOs tended to conserve a relatively high residual concentration of polyhydroxyalkanoates (PHAs) under aerobic conditions, while GAOs tended to deplete their available PHA more rapidly. This slower oxidation rate of PHA by PAOs at residual concentration levels enabled them to maintain an energy source for aerobic maintenance processes for longer than GAOs. This may provide PAOs with an advantage over GAOs in surviving the low organic loading conditions commonly found in full-scale wastewater treatment plants. PMID:25270044

  13. Radiocesium accumulation properties of Chengiopanax sciadophylloides.

    PubMed

    Sugiura, Yuki; Kanasashi, Tsutomu; Ogata, Yoshimune; Ozawa, Hajime; Takenaka, Chisato

    2016-01-01

    Through the assessments of radioactive contamination after the Fukushima Dai-ichi Nuclear Power Plant (F1NPP) accident, it has been reported that some sprouts of Chengiopanax sciadophylloides (Franch. et Sav.) at the site contained radiocesium (((134),)(137)Cs) at higher concentrations than the other plants. To assess the phytoremediation properties of C. sciadophylloides for (137)Cs decontamination, we aimed to quantify the (137)Cs accumulation in C. sciadophylloides. We measured the (137)Cs concentrations in various organs of C. sciadophylloides collected from the forest in the town of Kawamata, Fukushima prefecture, together with the concentrations of other elements [potassium (K), rubidium, (133)Cs, calcium, strontium, and manganese] present. In addition, we compared the foliar concentrations of these elements in C. sciadophylloides with those in four different deciduous tree species. The mean of foliar (137)Cs concentration in C. sciadophylloides was 28.1 kBq kg(-1) DW, one order of magnitude higher than that found in the other species. The (137)Cs concentrations were in the order of leaves > bark > wood. The wood of the treetop, leaf scars, and roots contained higher amounts of (137)Cs than that of the trunk. From the distribution of (137)Cs in C. sciadophylloides, we confirmed that (137)Cs tends to accumulate in the young growing parts. The difference in the distribution of (137)Cs and (133)Cs indicated that surface uptake of (137)Cs occurs. A significant correlation between K and (137)Cs concentrations in each organ was found, which suggested that (137)Cs in the plant body is transferred through the same pathway as K. On the other hand, there was no correlation between foliar K and (137)Cs concentrations, implying that the uptake ratio of K to (137)Cs was different for each individual. To determine the factors driving specific (137)Cs accumulation and/or the variability of the ratio between K and (137)Cs, the distribution of (137)Cs and the root in soil

  14. Radiocesium accumulation properties of Chengiopanax sciadophylloides.

    PubMed

    Sugiura, Yuki; Kanasashi, Tsutomu; Ogata, Yoshimune; Ozawa, Hajime; Takenaka, Chisato

    2016-01-01

    Through the assessments of radioactive contamination after the Fukushima Dai-ichi Nuclear Power Plant (F1NPP) accident, it has been reported that some sprouts of Chengiopanax sciadophylloides (Franch. et Sav.) at the site contained radiocesium (((134),)(137)Cs) at higher concentrations than the other plants. To assess the phytoremediation properties of C. sciadophylloides for (137)Cs decontamination, we aimed to quantify the (137)Cs accumulation in C. sciadophylloides. We measured the (137)Cs concentrations in various organs of C. sciadophylloides collected from the forest in the town of Kawamata, Fukushima prefecture, together with the concentrations of other elements [potassium (K), rubidium, (133)Cs, calcium, strontium, and manganese] present. In addition, we compared the foliar concentrations of these elements in C. sciadophylloides with those in four different deciduous tree species. The mean of foliar (137)Cs concentration in C. sciadophylloides was 28.1 kBq kg(-1) DW, one order of magnitude higher than that found in the other species. The (137)Cs concentrations were in the order of leaves > bark > wood. The wood of the treetop, leaf scars, and roots contained higher amounts of (137)Cs than that of the trunk. From the distribution of (137)Cs in C. sciadophylloides, we confirmed that (137)Cs tends to accumulate in the young growing parts. The difference in the distribution of (137)Cs and (133)Cs indicated that surface uptake of (137)Cs occurs. A significant correlation between K and (137)Cs concentrations in each organ was found, which suggested that (137)Cs in the plant body is transferred through the same pathway as K. On the other hand, there was no correlation between foliar K and (137)Cs concentrations, implying that the uptake ratio of K to (137)Cs was different for each individual. To determine the factors driving specific (137)Cs accumulation and/or the variability of the ratio between K and (137)Cs, the distribution of (137)Cs and the root in soil

  15. Cadmium accumulation in leaves of leafy vegetables.

    PubMed

    Baldantoni, Daniela; Morra, Luigi; Zaccardelli, Massimo; Alfani, Anna

    2016-01-01

    Leafy vegetables have a relatively high potential for Cd uptake and translocation, and are thus considered Cd accumulators. For this reason, leaves and roots of lettuce (Lactuca sativa L.) and endive (Cichorium endivia L.) plants, grown on different agricultural soils in Campania region (southern Italy), subjected to different fertilisation treatments (unfertilisation, compost amendment and mineral fertilisation), were analysed for Cd concentrations. Moreover, to clarify if the highest concentrations found are linked to older and inedible or to younger and edible leaves, external and internal endive leaves were separately analysed. All the leafy vegetables analysed showed on average 2-fold higher Cd concentrations in leaves than in roots. Leaf Cd concentrations in both lettuce and endive plants significantly differed among fertilisation treatments, with values highest in the plants grown on mineral fertilised soils. Apart from the soil fertilisation treatments, however, Cd leaf concentrations were often higher (up to 4-fold) than the threshold deduced by the EU 420/2011 Regulation, although the plants grew on unpolluted soils. Anyway, external leaves of endive plants showed significantly higher concentrations than internal leaves (in some cases the values were 3-fold higher), partly reassuring on the consumption of the younger leaves. Moreover, this study points out two major drawbacks in the Italian and European regulatory frameworks: (1) metal concentration (as total and/or available fraction) limits in agricultural soils are lacking; (2) metal concentration thresholds (currently existing only for Cd and Pb in crops) reported in the EU 420/2011 Regulation, expressed on the fresh weight basis rather than on the dry weight basis, appear not suitable.

  16. The accumulation of nickel in human lungs

    SciTech Connect

    Edelman, D.A.; Roggli, V.L. )

    1989-05-01

    Using data from published studies, lung concentrations of nickel were compare for persons with and without occupational exposure to nickel. As expected, the concentrations were much higher for persons with occupational exposure. To estimate the effects of nickel-containing tobacco smoke and nickel in the ambient air on the amount of nickel accumulated in lungs over time, a model was derived that took into account various variables related to the deposition of nickel in lungs. The model predicted nickel concentrations that were in the range of those of persons without known nickel exposure. Nickel is a suspected carcinogen and has been associated with an increased risk of respiratory tract cancer among nickel workers. However, before the nickel content of cigarettes can be implicated in the etiology of lung cancer, further studies are needed to evaluate the independent effects of smoking and exposure to nickel.

  17. Perceptions of breath alcohol concentration (BrAC) levels among a sample of bar patrons with BrAC values of 0.08% or higher.

    PubMed

    Martin, Ryan J; Chaney, Beth H; Cremeens-Matthews, Jennifer; Vail-Smith, Karen

    2016-09-01

    Breath alcohol concentration (BrAC) is a commonly used measure of alcohol intoxication. Because of the potential negative consequences of excessive alcohol consumption, it is important to examine how accurately intoxicated individuals can estimate their BrAC values, especially individuals over the legal BrAC driving threshold (i.e., 0.08%). To better understand perceptions of BrAC values among intoxicated individuals, this field study examined actual BrAC values and BrAC range estimates (0.08% and above, 0.02-0.07%, less than 0.02%) among a sample of bar patrons (N = 454) with BrAC levels at 0.08% or higher. Bivariate and multivariate analyses were conducted to examine the relationship between actual BrAC values and perceived BrAC levels. We also examined whether the following demographic and drinking variables were associated with underestimating BrAC in this sample: gender, age, race, college student status, plans to get home, and hazardous drinking. Results indicated that the majority (60.4%) of participants underestimated their BrAC (i.e., less than 0.08%) and lower BrAC values correlated with underestimating BrAC ranges (p < .001, 95% CI[0.2, 0.6]). Further, females (p = .001, 95% CI[1.3, 3.3]) and participants under 21 (p = .039, 95% CI = 1.0, 2.6) were significantly more likely to estimate their BrAC to be less than 0.08%, which is concerning given that young (less than 21) intoxicated females are a group at high risk for sexual assault on college campuses. (PsycINFO Database Record PMID:27631614

  18. N₂O accumulation from denitrification under different temperatures.

    PubMed

    Poh, Leong Soon; Jiang, Xie; Zhang, Zhongbo; Liu, Yu; Ng, Wun Jern; Zhou, Yan

    2015-11-01

    The effects of temperature on nitrous oxide (N2O) accumulation during denitrification and denitritation were investigated. Batch experiments were performed to measure N2O accumulation at 25 and 35 °C. More N2O accumulation was observed during denitritation at the higher temperature as compared with full denitrification and low temperature tests. The highest nitrite concentration tested in this study (25 mg/L NO2 (-)N and pH 8.0) did not show inhibitory effect on N2O reduction. It was found that the major cause of more N2O accumulation during denitrification at higher temperature was due to higher N2O production rate and lower N2O solubility. Specific nitrate, nitrite, and N2O reduction rates increased 62, 61, and 41 %, respectively, when temperature rose from 25 to 35 °C. The decrease of N2O solubility in mixed liquor at 35 °C (when compared to 25 °C) resulted in faster diffusing rate of N2O from liquid to gas phase. It was also more difficult for gas phase N2O to be re-dissolved. The diffused N2O was then accumulated in the headspace, which was not available for denitrification by denitrifiers. The results of this study suggest higher temperature may worsen N2O emission from wastewater treatment plants (WWTPs).

  19. Molybdenum accumulation in chlD mutants of Escherichia coli.

    PubMed Central

    Scott, D; Amy, N K

    1989-01-01

    The content of molybdenum in wild-type and chlD cells was measured under a variety of growth conditions to determine if cells with a defective chlD gene were able to accumulate molybdenum. The chlD cells accumulated less molybdenum than wild-type cells did but concentrated molybdenum to a level at least 20-fold higher than the concentration in the culture medium. Molybdenum was present within spheroplasts of chlD cells and was not dialyzable. The chlD cells accumulated as much molybdenum as wild-type cells did when grown in medium containing 0.1 mM molybdate; thus, the capability of incorporation of molybdenum into cellular component(s) was equivalent to that of the wild type under these conditions. PMID:2646274

  20. Field controlled experiments of mercury accumulation in crops from air and soil.

    PubMed

    Niu, Zhenchuan; Zhang, Xiaoshan; Wang, Zhangwei; Ci, Zhijia

    2011-10-01

    Field open top chambers (OTCs) and soil mercury (Hg) enriched experiments were employed to study the influence of Hg concentrations in air and soil on the Hg accumulation in the organs of maize (Zea mays L.) and wheat (Triticum aestivum L.). Results showed that Hg concentrations in foliages were correlated significantly (p < 0.05) with air Hg concentrations but insignificantly correlated with soil Hg concentrations, indicating that Hg in crop foliages was mainly from air. Hg concentrations in roots were generally correlated with soil Hg concentrations (p < 0.05) but insignificantly correlated with air Hg concentrations, indicating that Hg in crop roots was mainly from soil. No significant correlations were found between Hg concentrations in stems and those in air and soil. However, Hg concentrations in upper stems were usually higher than those in bottom stems, implying air Hg might have stronger influence than soil Hg on stem Hg accumulation.

  1. Experimental models of microcystin accumulation in Daphnia magna grazing on Planktothrix rubescens: implications for water management.

    PubMed

    Shams, Shiva; Cerasino, Leonardo; Salmaso, Nico; Dietrich, Daniel R

    2014-03-01

    In this study, we investigated the kinetic aspects of the microcystin (MC) transfer from Planktothrix rubescens to Daphnia magna by carrying out exposure experiments in small simple mesocosms. We hypothesized that higher fractions of toxic cyanobacteria in the diet of grazers would shift the balance towards a greater than linear, i.e. non-linear accumulation of MC in D. magna. This hypothesis was tested by exposing D. magna to varying initial densities of MC-producing P. rubescens. The evolving models of MC accumulation differed largely as a result of the duration of exposure and initial MC concentrations used. Within the first 24h of exposure, MC accumulation in D. magna was linear, irrespective of the initial densities of toxic P. rubescens and thus MC concentrations. After 48 h of exposure, MC accumulation in D. magna showed an exponential pattern, possibly due to a delayed digestion of P. rubescens and/or decreased MC detoxification capabilities when compared with higher ambient concentrations of MC. After 72 h toxin concentrations in Daphnia drop in all experiments as a consequence of the reduced cyanobacterial cells in the medium and the detoxification of MC within Daphnia. The results obtained suggest that in lakes with higher MC content and longer cyanobacterial bloom period MC accumulation in D. magna should be more pronounced than in mesotrophic lakes with lower MC content. The latter interpretation, however, should be verified investigating accumulation of MC both in larger mesocosms and in situ, in lakes of different trophic status.

  2. Accumulation of trace elements by Pistia stratiotes: implications for phytoremediation.

    PubMed

    Odjegba, V J; Fasidi, I O

    2004-10-01

    The toxicity of eight potentially toxic trace elements (Ag, Cd, Cr, Cu, Hg, Ni, Pb and Zn) to Pistia stratiotes was examined to determine if this plant showed sufficient tolerance and metal accumulation to be used to phytoremediate waste water and/or natural water bodies polluted with these heavy metals. Young plants of equal size were grown hydroponically and amended with 0, 0.1, 0.3, 0.5, 1.0, 3.0 and 5.0 mM of each heavy metal individually for 21 days. Root elongation as well as emergence of new roots decreased significantly with increase in metal concentrations. The plant had the lowest and the highest tolerance indices for Hg and Zn respectively. The study indicated reduction in the rate of leaf expansion relative to metal type, their concentrations and the duration of exposure. A significant reduction in biomass production was observed in metal treated plants compared with the control plants. The relative growth rate of P. stratiotes was retarded by heavy metals under study. All trace elements accumulated to higher concentrations in root tissue rather than in shoot. Trace element accumulation in tissues and the bioconcentration factors were proportional to the initial concentration of individual metals in the growth medium and the duration of exposure. In terms of trace element removal, P. stratiotes presented differential accumulation and tolerance levels for different metals at similar treatment conditions. The implications of these results for phytoremediation are discussed. PMID:15673213

  3. Study of fluxes at low concentrations of l-tri-iodothyronine with rat liver cells and their plasma-membrane vesicles. Evidence for the accumulation of the hormone against a gradient

    PubMed Central

    Rao, Govind S.; Rao, Marie Luise; Thilmann, Astrid; Quednau, Hans D.

    1981-01-01

    1. Influx and efflux of l-tri-[125I]iodothyronine with isolated rat liver parenchymal cells and their plasma-membrane vesicles were studied by a rapid centrifugation technique. 2. At 23°C and in the concentration range that included the concentration of free l-tri-iodothyronine in rat plasma (3–5pm) influx into cells was saturable; an apparent Kt value of 8.6±1.6pm was obtained. 3. At 5pm-l-tri-[125I]iodothyronine in the external medium the ratios of the concentrations inside to outside in cells and plasma-membrane vesicles were 38:1 and 366:1 respectively after 7s of incubation. At equilibrium (60s at 23°C) uptake of l-tri-[125I]iodothyronine by cells was linear with the hormone concentration, whereas that by plasma-membrane vesicles exhibited an apparent saturation with a Kd value of 6.1±1.3pm. 4. Efflux of l-tri-[125I]iodothyronine from cells equilibrated with the hormone (5–123pm) was constant up to 21 s; the amount that flowed out was 17.7±3.8% when cells were equilibrated with 5pm-hormone. When plasma-membrane vesicles were equilibrated with l-tri-[125I]iodothyronine (556–1226pm) 66.8±5.8% flowed out after 21 s. 5. From a consideration of the data on efflux from cells and binding of l-tri-[125I]iodothyronine to the liver homogenate, as studied by the charcoal-adsorption and equilibrium-dialysis methods, it appears that 18–22% of the hormone exists in the free form in the cell. 6. Vinblastine and colchicine diminished the uptake of l-tri-[125I]iodothyronine by cells but not by plasma-membrane vesicles; binding to the cytosol fraction was not affected. Phenylbutazone, 6-n-propyl-2-thiouracil, methimazole and corticosterone diminished the uptake by cells, plasma-membrane vesicles and binding to the cytosol fraction to different extents. 7. These results suggest that at low concentrations of l-tri-[125I]iodothyronine rat liver cells and their plasma-membrane vesicles accumulated the hormone against an apparent gradient by a membrane-mediated process

  4. Higher maternal plasma folate but not vitamin B-12 concentrations during pregnancy are associated with better cognitive function scores in 9- to 10- year-old children in South India.

    PubMed

    Veena, Sargoor R; Krishnaveni, Ghattu V; Srinivasan, Krishnamachari; Wills, Andrew K; Muthayya, Sumithra; Kurpad, Anura V; Yajnik, Chittaranjan S; Fall, Caroline H D

    2010-05-01

    Folate and vitamin B-12 are essential for normal brain development. Few studies have examined the relationship of maternal folate and vitamin B-12 status during pregnancy and offspring cognitive function. To test the hypothesis that lower maternal plasma folate and vitamin B-12 concentrations and higher plasma homocysteine concentrations during pregnancy are associated with poorer neurodevelopment, 536 children (aged 9-10 y) from the Mysore Parthenon birth cohort underwent cognitive function assessment during 2007-2008 using 3 core tests from the Kaufman Assessment Battery, and additional tests measuring learning, long-term storage/retrieval, attention and concentration, and visuo-spatial and verbal abilities. Maternal folate, vitamin B-12, and homocysteine concentrations were measured at 30 +/- 2 wk gestation. During pregnancy, 4% of mothers had low folate concentrations (<7 nmol/L), 42.5% had low vitamin B-12 concentrations (<150 pmol/L), and 3% had hyperhomocysteinemia (>10 micromol/L). The children's cognitive test scores increased by 0.1-0.2 SD per SD increase across the entire range of maternal folate concentrations (P < 0.001 for all), with no apparent associations at the deficiency level. The associations with learning, long-term storage/retrieval, visuo-spatial ability, attention, and concentration were independent of the parents' education, socioeconomic status, religion, and the child's sex, age, current size, and folate and vitamin B-12 concentrations. There were no consistent associations of maternal vitamin B-12 and homocysteine concentrations with childhood cognitive performance. In this Indian population, higher maternal folate, but not vitamin B-12, concentrations during pregnancy predicted better childhood cognitive ability. It also suggests that, in terms of neurodevelopment, the concentration used to define folate deficiency may be set too low. PMID:20335637

  5. Higher maternal plasma folate but not vitamin B-12 concentrations during pregnancy are associated with better cognitive function scores in 9- to 10- year-old children in South India.

    PubMed

    Veena, Sargoor R; Krishnaveni, Ghattu V; Srinivasan, Krishnamachari; Wills, Andrew K; Muthayya, Sumithra; Kurpad, Anura V; Yajnik, Chittaranjan S; Fall, Caroline H D

    2010-05-01

    Folate and vitamin B-12 are essential for normal brain development. Few studies have examined the relationship of maternal folate and vitamin B-12 status during pregnancy and offspring cognitive function. To test the hypothesis that lower maternal plasma folate and vitamin B-12 concentrations and higher plasma homocysteine concentrations during pregnancy are associated with poorer neurodevelopment, 536 children (aged 9-10 y) from the Mysore Parthenon birth cohort underwent cognitive function assessment during 2007-2008 using 3 core tests from the Kaufman Assessment Battery, and additional tests measuring learning, long-term storage/retrieval, attention and concentration, and visuo-spatial and verbal abilities. Maternal folate, vitamin B-12, and homocysteine concentrations were measured at 30 +/- 2 wk gestation. During pregnancy, 4% of mothers had low folate concentrations (<7 nmol/L), 42.5% had low vitamin B-12 concentrations (<150 pmol/L), and 3% had hyperhomocysteinemia (>10 micromol/L). The children's cognitive test scores increased by 0.1-0.2 SD per SD increase across the entire range of maternal folate concentrations (P < 0.001 for all), with no apparent associations at the deficiency level. The associations with learning, long-term storage/retrieval, visuo-spatial ability, attention, and concentration were independent of the parents' education, socioeconomic status, religion, and the child's sex, age, current size, and folate and vitamin B-12 concentrations. There were no consistent associations of maternal vitamin B-12 and homocysteine concentrations with childhood cognitive performance. In this Indian population, higher maternal folate, but not vitamin B-12, concentrations during pregnancy predicted better childhood cognitive ability. It also suggests that, in terms of neurodevelopment, the concentration used to define folate deficiency may be set too low.

  6. Soil aluminium uptake and accumulation by Paspalum notatum.

    PubMed

    Huang, Juan; Xia, Hanping; Li, Zhi'an; Xiong, Yanmei; Kong, Guohui; Huang, Juan

    2009-10-01

    Paspalum notatum Flugge has been widely utilized for the purpose of ecological restoration of degraded land in the tropics and subtropics, where soil active aluminium (Al) is usually high as a result of acidification. Pot experiments were conducted to determine Al toxicity on P. notatum and to compare its potential to remove Al with another three plant species, Vetiveria zizanioides, Tristania conferta and Schima wallichii. In the Al addition experiment, the biomass of P. notatum and Al accumulation significantly decreased as the added Al concentration increased, but Al concentration in the plant markedly increased. A parallel experiment was conducted with the above four species, grown in lateritic soil and in oil shale waste containing high concentration of active Al. The biomasses of all four species were reduced obviously in the waste compared to in the soil. The effects of substrate on Al concentration, accumulation and translocation efficiency differed among species, and plants had significantly higher Al accumulation factors when grown in the soil than in the waste. Most of the Al taken up by P. notatum was transferred to above-ground parts; as a result, Al concentration in stems and leaves became quite high, over 1000 or even 3000 mg kg(-1); whereas for the other three species, Al concentration in shoots was much lower than in roots. Paspalum notatum was therefore much higher than the other three species with regard to Al translocation efficiency and therefore P. notatum may be regarded as both an effective Al hyper-accumulator and a potential Al hyper-remover.

  7. Spatial distribution of heavy metal accumulation in the sediments after dam construction.

    PubMed

    Shim, Moo Joon; Yang, Yun Mo; Oh, Da Yeon; Lee, Soo Hyung; Yoon, Yi Yong

    2015-12-01

    The sedimentary environment has been modified in the Geum River where an estuary dam and midstream dams were constructed. Furthermore, the Geum River tributaries deliver contaminants from the wastewater of an industrial complex. However, the influence of tributaries and dams on sedimentary metal deposition has not been extensively studied. The objectives of this study are to assess metal accumulation and to investigate the source of the metals. Sediments were collected in the main channel and two tributaries on October 2013. Abnormal accumulations of fine sediments were not observed above the midstream dams. Chromium, Ni, and Zn showed higher concentrations in above the midstream dam, but their concentrations were not related to grain size. Cadmium, Cu, Pb, and Hg were much higher upstream from the first midstream dam and came from one of the major tributaries. Arsenic was the only element found at higher concentrations downstream from the last midstream dam and was likely sourced from abandoned mines and/or agricultural activity. The pollution indexes indicated deposition of all metals, except Cr and Ni, may have been affected by anthropogenic activity. With respect to long-term accumulation of the metals, accumulation of Pb, Zn, and Cu by anthropogenic input largely increased, implying accumulation of these metals has continued due to anthropogenic activity since the estuary dam was constructed. Our results suggest that changes in river flow caused by the estuary dam and anthropogenic input from tributaries sources increased the accumulation of heavy metals (e.g., Pb, Zn, Cu, and As). PMID:26549487

  8. Spatial distribution of heavy metal accumulation in the sediments after dam construction.

    PubMed

    Shim, Moo Joon; Yang, Yun Mo; Oh, Da Yeon; Lee, Soo Hyung; Yoon, Yi Yong

    2015-12-01

    The sedimentary environment has been modified in the Geum River where an estuary dam and midstream dams were constructed. Furthermore, the Geum River tributaries deliver contaminants from the wastewater of an industrial complex. However, the influence of tributaries and dams on sedimentary metal deposition has not been extensively studied. The objectives of this study are to assess metal accumulation and to investigate the source of the metals. Sediments were collected in the main channel and two tributaries on October 2013. Abnormal accumulations of fine sediments were not observed above the midstream dams. Chromium, Ni, and Zn showed higher concentrations in above the midstream dam, but their concentrations were not related to grain size. Cadmium, Cu, Pb, and Hg were much higher upstream from the first midstream dam and came from one of the major tributaries. Arsenic was the only element found at higher concentrations downstream from the last midstream dam and was likely sourced from abandoned mines and/or agricultural activity. The pollution indexes indicated deposition of all metals, except Cr and Ni, may have been affected by anthropogenic activity. With respect to long-term accumulation of the metals, accumulation of Pb, Zn, and Cu by anthropogenic input largely increased, implying accumulation of these metals has continued due to anthropogenic activity since the estuary dam was constructed. Our results suggest that changes in river flow caused by the estuary dam and anthropogenic input from tributaries sources increased the accumulation of heavy metals (e.g., Pb, Zn, Cu, and As).

  9. Low iron stores are related to higher blood concentrations of manganese, cobalt and cadmium in non-smoking, Norwegian women in the HUNT 2 study

    SciTech Connect

    Margrete Meltzer, Helle; Lise Brantsaeter, Anne; Borch-Iohnsen, Berit; Ellingsen, Dag G.; Alexander, Jan; Thomassen, Yngvar; Stigum, Hein; Ydersbond, Trond A.

    2010-07-15

    Low iron (Fe) stores may influence absorption or transport of divalent metals in blood. To obtain more knowledge about such associations, the divalent metal ions cadmium (Cd), manganese (Mn), cobalt (Co), copper (Cu), zinc (Zn) and lead (Pb) and parameters of Fe metabolism (serum ferritin, haemoglobin (Hb) and transferrin) were investigated in 448 healthy, menstruating non-smoking women, age 20-55 years (mean 38 years), participating in the Norwegian HUNT 2 study. The study population was stratified for serum ferritin: 257 were iron-depleted (serum ferritin <12 {mu}g/L) and 84 had iron deficiency anaemia (serum ferritin <12 {mu}g/L and Hb<120 g/L). The low ferritin group had increased blood concentrations of Mn, Co and Cd but normal concentrations of Cu, Zn and Pb. In multiple regression models, ferritin emerged as the main determinant of Mn, Co and Cd (p<0.001), while no significant associations with Cu, Zn and Pb were found. Adjusted r{sup 2} for the models were 0.28, 0.48 and 0.34, respectively. Strong positive associations between blood concentrations of Mn, Co and Cd were observed, also when controlled for their common association with ferritin. Apart from these associations, the models showed no significant interactions between the six divalent metals studied. Very mild anaemia (110{<=}Hb<120 g/L) did not seem to have any effect independent of low ferritin. Approximately 26% of the women with iron deficiency anaemia had high concentrations of all of Mn, Co and Cd as opposed to 2.3% of iron-replete subjects. The results confirm that low serum ferritin may have an impact on body kinetics of certain divalent metal ions, but not all. Only a fraction of women with low iron status exhibited an increased blood concentration of divalent metals, providing indication of complexities in the body's handling of these metals.

  10. Concentrations of higher dicarboxylic acids C5-C13 in fresh snow samples collected at the High Alpine Research Station Jungfraujoch during CLACE 5 and 6

    NASA Astrophysics Data System (ADS)

    Winterhalter, R.; Kippenberger, M.; Williams, J.; Fries, E.; Sieg, K.; Moortgat, G. K.

    2009-03-01

    Samples of freshly fallen snow were collected at the high alpine research station Jungfraujoch (Switzerland) in February and March 2006 and 2007, during the Cloud and Aerosol Characterization Experiments (CLACE) 5 and 6. In this study a new technique has been developed and demonstrated for the measurement of organic acids in fresh snow. The melted snow samples were subjected to solid phase extraction and resulting solutions analysed for organic acids by HPLC-MS-TOF using negative electrospray ionization. A series of linear dicarboxylic acids from C5 to C13 and phthalic acid, were identified and quantified. In several samples the biogenic acid pinonic acid was also observed. In fresh snow the median concentration of the most abundant acid, adipic acid, was 0.69 μg L-1 in 2006 and 0.70 μg L-1 in 2007. Glutaric acid was the second most abundant dicarboxylic acid found with median values of 0.46 μg L-1 in 2006 and 0.61 μg L-1 in 2007, while the aromatic acid phthalic acid showed a median concentration of 0.34 μg L-1 in 2006 and 0.45 μg L-1 in 2007. The concentrations in the samples from various snowfall events varied significantly, and were found to be dependent on the back trajectory of the air mass arriving at Jungfraujoch. Air masses of marine origin showed the lowest concentrations of acids whereas the highest concentrations were measured when the air mass was strongly influenced by boundary layer air.

  11. Concentrations of higher dicarboxylic acids C5-C13 in fresh snow samples collected at the High Alpine Research Station Jungfraujoch during CLACE 5 and 6

    NASA Astrophysics Data System (ADS)

    Winterhalter, R.; Kippenberger, M.; Williams, J.; Fries, E.; Sieg, K.; Moortgat, G. K.

    2008-10-01

    Samples of freshly fallen snow were collected at the high alpine research station Jungfraujoch (Switzerland) in February and March 2006 and 2007, during the Cloud and Aerosol Characterization Experiments (CLACE) 5 and 6. In this study a new technique has been developed and demonstrated for the measurement of organic acids in fresh snow. The melted snow samples were subjected to solid phase extraction and resulting solution analysed for organic acids by HPLC-MS-TOF using negative electrospray ionization. A series of linear dicarboxylic acids from C5 to C13 and phthalic acid, were identified and quantified. In several samples the biogenic acid pinonic acid was also observed. In fresh snow the median concentration of the most abundant acid, adipic acid, was 0.69 μg L-1 in 2006 and 0.70 μg L-1 in 2007. Glutaric acid was the second most abundant dicarboxylic acid found with median values of 0.46 μg L-1 in 2006 and 0.61 μg L-1 in 2007, while the aromatic acid phthalic acid showed a median concentration of 0.34 μg L-1 in 2006 and 0.45 μg L-1 in 2007. The concentrations in the samples from various snowfall events varied significantly, and were found to be dependent on the back trajectory of the air mass arriving at Jungfraujoch. Air masses of marine origin showed the lowest concentrations of acids whereas the highest concentrations were measured when the air mass was strongly influenced by boundary layer air.

  12. Higher maternal plasma folate but not vitamin B-12 concentrations during pregnancy are associated with better cognitive function scores in 9-10 year old children in South-India1-3

    PubMed Central

    Veena, Sargoor R; Krishnaveni, Ghattu V; Srinivasan, Krishnamachari; Wills, Andrew K; Muthayya, Sumithra; Kurpad, Anura V; Yajnik, Chittaranjan S; Fall, Caroline HD

    2012-01-01

    Folate and vitamin B-12 (B-12) are essential for normal brain development. Few studies have examined the relationship of maternal folate and B-12 status during pregnancy to offspring cognitive function. To test the hypothesis that lower maternal plasma folate and B-12 concentrations and higher plasma homocysteine concentrations during pregnancy, are associated with poorer neurodevelopment, cognitive function was assessed during 2007-2008 among 536 children (aged 9-10 y) from the Mysore Parthenon birth cohort. Maternal folate, B-12 and homocysteine concentrations were measured in stored plasma samples taken at 30±2 wk gestation. The children’s cognitive function was measured using 3 core tests from the Kaufman Assessment Battery and additional tests measuring learning ability, long-term storage/retrieval, attention and concentration, visuo-spatial and verbal abilities. During pregnancy 4% of mothers had low folate concentrations (<7 nmol/L), 42.5% had low B-12 concentrations (<150 pmol/L) and 3% had hyperhomocysteinemia (>10 μmol/L). There was a 0.1-0.2 SD increase in the children’s cognitive scores per SD increase in maternal folate concentration (p<0.001 for all tests). The associations with learning ability and long-term storage/retrieval, visuo-spatial ability, attention and concentration were independent of maternal age, BMI, parity, the parents’ education, socio-economic status, rural/urban residence, religion, the child’s gestational age, birth size, sex and the children’s size, educational level and folate and B-12 concentrations at 9.5 y. There were no consistent associations of maternal B-12 and homocysteine concentrations with childhood cognitive performance. Conclusions In this Indian population higher maternal folate, but not vitamin B-12 concentrations during pregnancy, predicted better childhood cognitive ability. PMID:20335637

  13. Role of transpiration in arsenic accumulation of hyperaccumulator Pteris vittata L.

    PubMed

    Wan, Xiao-ming; Lei, Mei; Chen, Tong-bin; Yang, Jun-xing; Liu, Hong-tao; Chen, Yang

    2015-11-01

    Mechanisms of Pteris vittata L. to hyperaccumulate arsenic (As), especially the efficient translocation of As from rhizoids to fronds, are not clear yet. The present study aims to investigate the role of transpiration in the accumulation of As from the aspects of transpiration regulation and ecotypic difference. Results showed that As accumulation of P. vittata increased proportionally with an increase in the As exposure concentration. Lowering the transpiration rate by 28∼67% decreased the shoot As concentration by 19∼56%. Comparison of As distribution under normal treatment and shade treatment indicated that transpiration determines the distribution pattern of As in pinnae. In terms of the ecotypic difference, the P. vittata ecotype from moister and warmer habitat had 40% higher transpiration and correspondingly 40% higher shoot As concentration than the ecotype from drier and cooler habitat. Results disclosed that transpiration is the main driver for P. vittata to accumulate and re-distribute As in pinnae.

  14. Cow allergen (Bos d2) and endotoxin concentrations are higher in the settled dust of homes proximate to industrial-scale dairy operations

    PubMed Central

    Williams, D' Ann L; McCormack, Meredith C; Matsui, Elizabeth C; Diette, Gregory B; McKenzie, Shawn E; Geyh, Alison S; Breysse, Patrick N

    2016-01-01

    Airborne contaminants produced by industrial agricultural facilities contain chemical and biological compounds that can impact the health of residents living in close proximity. Settled dust can be a reservoir for these contaminants and can influence long-term exposures. In this study, we sampled the indoor- and outdoor-settled dust from 40 homes that varied in proximity to industrial-scale dairies (ISD; industrial-scale dairy, a term used in this paper to describe a large dairy farm and adjacent waste sprayfields, concentrated animal feeding operation or animal feeding operation, that uses industrial processes) in the Yakima Valley, Washington. We analyzed settled dust samples for cow allergen (Bos d2, a cow allergen associated with dander, hair, sweat and urine, it is a member of the lipocalin family of allergens associated with mammals), mouse allergen (Mus m1; major mouse allergen, a mouse urinary allergen, in the lipocalin family), dust mite allergens (Der p1 (Dermatophagoides pteronissinus 1) and Der f1 (Dermatophagoides farinae 1)), and endotoxin (a component of the cell walls of gram negative bacteria, lipopolysaccharide, which can be found in air and dust and can produce a strong inflammatory response). A concentration gradient was observed for Bos d2 and endotoxin measured in outdoor-settled dust samples based on proximity to ISD. Indoor-settled dust concentrations of Bos d2 and endotoxin were also highest in proximal homes. While the associated health effects of exposure to cow allergen in settled dust is unknown, endotoxin at concentrations observed in these proximal homes (100 EU/mg) has been associated with increased negative respiratory health effects. These findings document that biological contaminants emitted from ISDs are elevated in indoor- and outdoor-settled dust samples at homes close to these facilities and extend to as much as three miles (4.8 km) away. PMID:25138294

  15. Myocardial accumulation of iodinated beta-methyl-branched fatty acid analogue, iodine-125-15-(p-iodophenyl)-3-(R,S)methylpentadecanoic acid (BMIPP), in relation to ATP concentration

    SciTech Connect

    Fujibayashi, Y.; Yonekura, Y.; Takemura, Y.; Wada, K.; Matsumoto, K.; Tamaki, N.; Yamamoto, K.; Konishi, J.; Yokoyama, A. )

    1990-11-01

    To clarify the relationship between the myocardial accumulation of {sup 125}I-15-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid (BMIPP) and intracellular adenosine-5'-triphosphate (ATP) content, the effect of 2,4-dinitrophenol (DNP, an electron transport uncoupler) on myocardial BMIPP accumulation was studied, in comparison with that of thallium-201-chloride ({sup 201}Tl-Cl). In the mouse myocardium, DNP decreased the intracellular ATP and ADP levels, without affecting either acyl-CoA synthetase activity or the level of CoA-SH. Following treatment with DNP, decreases in myocardial BMIPP accumulation correlated well with those of ATP, while {sup 201}Tl-Cl showed slightly increased accumulation in the myocardium. Thus, in some diseases, BMIPP may be useful in evaluating myocardial ATP levels.

  16. Accumulation of mercury and methylmercury by mushrooms and earthworms from forest soils.

    PubMed

    Rieder, Stephan R; Brunner, Ivano; Horvat, Milena; Jacobs, Anna; Frey, Beat

    2011-10-01

    Accumulation of total and methyl-Hg by mushrooms and earthworms was studied in thirty-four natural forest soils strongly varying in soil physico-chemical characteristics. Tissue Hg concentrations of both receptors did hardly correlate with Hg concentrations in soil. Both total and methyl-Hg concentrations in tissues were species-specific and dependent on the ecological groups of receptor. Methyl-Hg was low accounting for less than 5 and 8% of total Hg in tissues of mushrooms and earthworms, respectively, but with four times higher concentrations in earthworms than mushrooms. Total Hg concentrations in mushrooms averaged 0.96 mg Hg kg(-1) dw whereas litter decomposing mushrooms showed highest total Hg and methyl-Hg concentrations. Earthworms contained similar Hg concentrations (1.04 mg Hg kg(-1) dw) whereas endogeic earthworms accumulated highest amounts of Hg and methyl-Hg.

  17. Accumulation of mercury and methylmercury by mushrooms and earthworms from forest soils.

    PubMed

    Rieder, Stephan R; Brunner, Ivano; Horvat, Milena; Jacobs, Anna; Frey, Beat

    2011-10-01

    Accumulation of total and methyl-Hg by mushrooms and earthworms was studied in thirty-four natural forest soils strongly varying in soil physico-chemical characteristics. Tissue Hg concentrations of both receptors did hardly correlate with Hg concentrations in soil. Both total and methyl-Hg concentrations in tissues were species-specific and dependent on the ecological groups of receptor. Methyl-Hg was low accounting for less than 5 and 8% of total Hg in tissues of mushrooms and earthworms, respectively, but with four times higher concentrations in earthworms than mushrooms. Total Hg concentrations in mushrooms averaged 0.96 mg Hg kg(-1) dw whereas litter decomposing mushrooms showed highest total Hg and methyl-Hg concentrations. Earthworms contained similar Hg concentrations (1.04 mg Hg kg(-1) dw) whereas endogeic earthworms accumulated highest amounts of Hg and methyl-Hg. PMID:21621314

  18. Solids Accumulation Scouting Studies

    SciTech Connect

    Duignan, M. R.; Steeper, T. J.; Steimke, J. L.

    2012-09-26

    The objective of Solids Accumulation activities was to perform scaled testing to understand the behavior of remaining solids in a Double Shell Tank (DST), specifically AW-105, at Hanford during multiple fill, mix, and transfer operations. It is important to know if fissionable materials can concentrate when waste is transferred from staging tanks prior to feeding waste treatment plants. Specifically, there is a concern that large, dense particles containing plutonium could accumulate in poorly mixed regions of a blend tank heel for tanks that employ mixing jet pumps. At the request of the DOE Hanford Tank Operations Contractor, Washington River Protection Solutions, the Engineering Development Laboratory of the Savannah River National Laboratory performed a scouting study in a 1/22-scale model of a waste staging tank to investigate this concern and to develop measurement techniques that could be applied in a more extensive study at a larger scale. Simulated waste tank solids: Gibbsite, Zirconia, Sand, and Stainless Steel, with stainless steel particles representing the heavier particles, e.g., plutonium, and supernatant were charged to the test tank and rotating liquid jets were used to mix most of the solids while the simulant was pumped out. Subsequently, the volume and shape of the mounds of residual solids and the spatial concentration profiles for the surrogate for heavier particles were measured. Several techniques were developed and equipment designed to accomplish the measurements needed and they included: 1. Magnetic particle separator to remove simulant stainless steel solids. A device was designed and built to capture these solids, which represent the heavier solids during a waste transfer from a staging tank. 2. Photographic equipment to determine the volume of the solids mounds. The mounds were photographed as they were exposed at different tank waste levels to develop a composite of topographical areas. 3. Laser rangefinders to determine the volume of

  19. Pensions and Household Wealth Accumulation

    ERIC Educational Resources Information Center

    Engelhardt, Gary V.; Kumar, Anil

    2011-01-01

    Economists have long suggested that higher private pension benefits "crowd out" other sources of household wealth accumulation. We exploit detailed information on pensions and lifetime earnings for older workers in the 1992 wave of the Health and Retirement Study and employ an instrumental-variable (IV) identification strategy to estimate…

  20. Methylotrophic bacteria symbiosis with the higher plants as means of minimization of the lower hydrocarbons concentration during artificial ecosystem gas exchange

    NASA Astrophysics Data System (ADS)

    Berkovich, Yuliy; Smolyanina, Svetlana; Moukhamedieva, Lana; Mardanov, Robert; Doronina, Nina; Ivanova, Ekaterina

    Plant growth unit should be included in the LSS for the space vehicles for vitamin greens supply and psychological support of cosmonauts during long-term missions. The lower hydrocarbons such as methane, methanol, methylated sulfuric compounds and methylated amines, ethylene and so on, are the natural products of human and plant metabolism and usually considered as the air pollutions. It is shown, that one way to decrease the lower hydrocarbons concentration in the artificial ecosystems could be colonization of the plants by methylotrophic bacteria. The aerobic methylotrophic bacteria possess unique ability to use methane and its oxidized or replaced derivatives without food damage and human, animals or plants infection. We have found that methylotrophic bacteria are the phyto-symbiotic bacteria: they stimulate growth and development of the colonized plants because of synthesizing cytokinins and auxins, and vitamin B12.Two collection strains of the obligate methylotrophic bacteria - Methylovorus mays C and Methylomonas metanica S - were chosen because of their high activity to assimilate the lower hydrocarbons due to functioning of methanoldehydrogenase, methanmonooxigenase and ribulose monophosphate cycle enzymes system.Colonization of the leaf cabbage Brassica chinensis L. by these strains led to approximately 30 % reduce of methanol and methane concentration in the air inside phytotron. Experimental estimations of the influence of methylotrophic bacteria on leafy greens growth and development are obtained.

  1. Stable strontium accumulation by earthworms: a paradigm for radiostrontium interactions with its cationic analogue, calcium.

    PubMed

    Morgan, J E; Richards, S P; Morgan, A J

    2001-06-01

    The accumulation of stable strontium and its chemical analogue calcium by four species of earthworm, representing three distinct ecophysiological groups inhabiting celestite (SrSO4)-rich natural soils, was investigated. An increase in soil strontium concentration over a four-orders-of-magnitude range was accompanied by an increase in earthworm tissue strontium concentration. In contrast, no relationship between soil and tissue calcium concentrations was apparent, indicating that this essential cation is strongly regulated within earthworm tissues but that nonessential strontium burdens are not physiologically regulated. Concentration factors for strontium ranged from 0.1 to 1.42, with an inverse relationship between this parameter and soil strontium concentration. The use of concentration factors and discrimination coefficients lead to the conclusion that earthworms discriminate against strontium accumulation at increased soil calcium concentrations, such that strontium would be predicted to be more efficiently accumulated by worms inhabiting acidic, calcium-poor soils. Although few consistent trends in strontium and calcium concentration were apparent between earthworm species, the species with the highest calcium turnover (i.e., the litter-inhabiting Lumbricus rubellus) typically accumulated higher concentrations of strontium than representatives of contrasting ecophysiological classes. These findings are considered in the context of the distribution, retention, and cycling of radiostrontium in soils.

  2. Influence of life history and sex on metal accumulation in two beetle species (insecta: Coleoptera)

    SciTech Connect

    Lindqvist, L.; Block, M.

    1997-04-01

    Insects are important components of most terrestrial environments owing to their great abundance, biomass and diversity. They also make up an important food resource for other animals. Consequently, in many food webs insects constitute important links in metal-transport chains between trophic levels. Therefore trace-metal concentrations in insects have an important influence on the trace-metal distribution in the biosphere. In various insects, Cd, Cu and Zn are usually accumulated to the extent that they reach levels above those of the food, whereas Fe is not. In response to metal pollution, accumulation of nonessential metals was found to increase markedly, whereas essential metals accumulated less owing to regulating mechanisms in the insects. In polluted environments, metal concentrations were found to be higher in predatory invertebrates than in phytophagous ones in studies where insects were analysed in broad categories such as families. However, no such trend was observed when species were treated separately. The pattern of metal accumulation can differ between species. This is true even for species utilizing the same food resource. For instance, concentrations of Cd, Cu and Fe differed between four species of sawflies feeding on pine needles from the same locality. It is therefore likely that insects with different food sources accumulate metals differently depending on the concentration and chemical form of the metals in the food. There have been few studies aimed at determining whether patterns of metal accumulation differ between males and females of the same species. In one such study on the sawfly Neodiprion sertifer concentrations of Cd, Cu and Fe tended to be higher in males than in females. However, this pattern was not found in two other sawfly species. Target organs for Cd were found to differ between males and females in the grasshopper Aiolopus thalassinus. The testis accumulated Cd to a higher degree than the ovaries.

  3. Copper accumulation by stickleback nests containing spiggin.

    PubMed

    Pinho, G L L; Martins, C M G; Barber, I

    2016-07-01

    The three-spined stickleback is a ubiquitous fish of marine, brackish and freshwater ecosystems across the Northern hemisphere that presents intermediate sensitivity to copper. Male sticklebacks display a range of elaborate reproductive behaviours that include nest construction. To build the nests, each male binds nesting material together using an endogenous glycoprotein nesting glue, known as 'spiggin'. Spiggin is a cysteine-rich protein and, therefore, potentially binds heavy metals present in the environment. The aim of this study was to investigate the capacity of stickleback nests to accumulate copper from environmental sources. Newly built nests, constructed by male fish from polyester threads in laboratory aquaria, were immersed in copper solutions ranging in concentration from 21.1-626.6 μg Cu L(-1). Bundles of polyester threads from aquaria without male fish were also immersed in the same copper solutions. After immersion, nests presented higher amounts of copper than the thread bundles, indicating a higher capacity of nests to bind this metal. A significant, positive correlation between the concentration of copper in the exposure solution and in the exposed nests was identified, but there was no such relationship for thread bundles. Since both spiggin synthesis and male courtship behaviour are under the control of circulating androgens, we predicted that males with high courtship scores would produce and secrete high levels of the spiggin protein. In the present study, nests built by high courtship score males accumulated more copper than those built by low courtship score males. Considering the potential of spiggin to bind metals, the positive relationship between fish courtship and spiggin secretion seems to explain the higher amount of copper on the nests from the fish showing high behaviour scores. Further work is now needed to determine the consequences of the copper binding potential of spiggin in stickleback nests for the health and survival of

  4. Nutrient-contaminant (Pu) plant accumulation model

    SciTech Connect

    Cowan, C.E.; Jenne, E.A.; Simpson, J.C.; Cataldo, D.A.

    1981-12-01

    A model was developed which simulates the movement and daily accumulation of nutrients and contaminants in crop plants resulting from known physiological processes in the plant. In the model, the daily contaminant accumulation is governed by daily increase in plant biomass derived from photosynthesis and by the specified thermodynamic activity of the bioavailable contaminant species in soil or hydroponic solutin. Total accumulation and resulting concentration in the plant's root, stem and branch, leaf, and reproductive compartments can be simulated any time during the growing season. Parameters were estimated from data on plutonium accumulation in soybeans and the model was calibrated against this same data set. The plutonium distribution in the plant was found to be most sensitive to parameters related to leaf accumulation. Contamination at different times during the growing season resulted in a large change in predicted leaf accumulation but very little change in predicted accumulation in other plant parts except when contamination occurred very late in the growing season.

  5. Synergy of fresh and accumulated organic matter to bacterial growth.

    PubMed

    Farjalla, Vinicius F; Marinho, Claudio C; Faria, Bias M; Amado, André M; Esteves, Francisco de A; Bozelli, Reinaldo L; Giroldo, Danilo

    2009-05-01

    The main goal of this research was to evaluate whether the mixture of fresh labile dissolved organic matter (DOM) and accumulated refractory DOM influences bacterial production, respiration, and growth efficiency (BGE) in aquatic ecosystems. Bacterial batch cultures were set up using DOM leached from aquatic macrophytes as the fresh DOM pool and DOM accumulated from a tropical humic lagoon. Two sets of experiments were performed and bacterial growth was followed in cultures composed of each carbon substrate (first experiment) and by carbon substrates combined (second experiment), with and without the addition of nitrogen and phosphorus. In both experiments, bacterial production, respiration, and BGE were always higher in cultures with N and P additions, indicating a consistent inorganic nutrient limitation. Bacterial production, respiration, and BGE were higher in cultures set up with leachate DOM than in cultures set up with humic DOM, indicating that the quality of the organic matter pool influenced the bacterial growth. Bacterial production and respiration were higher in the mixture of substrates (second experiment) than expected by bacterial production and respiration in single substrate cultures (first experiment). We suggest that the differences in the concentration of some compounds between DOM sources, the co-metabolism on carbon compound decomposition, and the higher diversity of molecules possibly support a greater bacterial diversity which might explain the higher bacterial growth observed. Finally, our results indicate that the mixture of fresh labile and accumulated refractory DOM that naturally occurs in aquatic ecosystems could accelerate the bacterial growth and bacterial DOM removal. PMID:18985269

  6. Heavy metal accumulation and source analysis in greenhouse soils of Wuwei District, Gansu Province, China.

    PubMed

    Bai, L Y; Zeng, X B; Su, S M; Duan, R; Wang, Y N; Gao, X

    2015-04-01

    Greenhouse soils and arable (wheat field) soil samples were collected to identify the effects of greenhouse cultivation on the accumulation of six heavy metals (Cd, Cu, Zn, Pb, Cr, and Ni) and to evaluate the likely sources responsible for heavy metal accumulation in the irrigated desert soils of Wuwei District, China. The results indicated that the mean concentrations of Cd, Cu, Zn, Pb, Cr, and Ni were 0.421, 33.85, 85.31, 20.76, 53.12, and 28.59 mg kg(-1), respectively. The concentrations of Cd, Cu, and Zn in greenhouse soils were 60, 23, and 14% higher than those in arable soils and 263, 40, and 25% higher than background concentrations of natural soils in the study area, respectively. These results indicated that Cd, Cu, and Zn accumulation occurred in the greenhouse soils, and Cd was the most problematically accumulated heavy metal, followed by Cu and Zn. There was a significant positive correlation between the concentrations of Cd, Cu, and Zn in greenhouse soils and the number of years under cultivation (P < 0.05). Greenhouse cultivation had little impact on the accumulation of Cr, Ni, or Pb. Correlation analysis and principal component analysis suggested that the accumulation of Cd, Cu, and Zn in greenhouse soils resulted mainly from fertilizer applications. Our results indicated that the excessive and long-term use of fertilizers and livestock manures with high heavy metal levels leads to the accumulation of heavy metals in soils. Therefore, rational fertilization programs and reductions in the concentrations of heavy metals in both fertilizers and manure must be recommended to maintain a safe concentration of heavy metals in greenhouse soils.

  7. Consumption of meat is associated with higher fasting glucose and insulin concentrations regardless of glucose and insulin genetic risk scores: a meta-analysis of 50,345 Caucasians12

    PubMed Central

    Fretts, Amanda M; Follis, Jack L; Nettleton, Jennifer A; Lemaitre, Rozenn N; Ngwa, Julius S; Wojczynski, Mary K; Kalafati, Ioanna Panagiota; Varga, Tibor V; Frazier-Wood, Alexis C; Houston, Denise K; Lahti, Jari; Ericson, Ulrika; van den Hooven, Edith H; Mikkilä, Vera; Kiefte-de Jong, Jessica C; Mozaffarian, Dariush; Rice, Kenneth; Renström, Frida; North, Kari E; McKeown, Nicola M; Feitosa, Mary F; Kanoni, Stavroula; Smith, Caren E; Garcia, Melissa E; Tiainen, Anna-Maija; Sonestedt, Emily; Manichaikul, Ani; van Rooij, Frank JA; Dimitriou, Maria; Raitakari, Olli; Pankow, James S; Djoussé, Luc; Province, Michael A; Hu, Frank B; Lai, Chao-Qiang; Keller, Margaux F; Perälä, Mia-Maria; Rotter, Jerome I; Hofman, Albert; Graff, Misa; Kähönen, Mika; Mukamal, Kenneth; Johansson, Ingegerd; Ordovas, Jose M; Liu, Yongmei; Männistö, Satu; Uitterlinden, André G; Deloukas, Panos; Seppälä, Ilkka; Psaty, Bruce M; Cupples, L Adrienne; Borecki, Ingrid B; Franks, Paul W; Arnett, Donna K; Nalls, Mike A; Eriksson, Johan G; Orho-Melander, Marju; Franco, Oscar H; Lehtimäki, Terho; Dedoussis, George V; Meigs, James B; Siscovick, David S

    2015-01-01

    Background: Recent studies suggest that meat intake is associated with diabetes-related phenotypes. However, whether the associations of meat intake and glucose and insulin homeostasis are modified by genes related to glucose and insulin is unknown. Objective: We investigated the associations of meat intake and the interaction of meat with genotype on fasting glucose and insulin concentrations in Caucasians free of diabetes mellitus. Design: Fourteen studies that are part of the Cohorts for Heart and Aging Research in Genomic Epidemiology consortium participated in the analysis. Data were provided for up to 50,345 participants. Using linear regression within studies and a fixed-effects meta-analysis across studies, we examined 1) the associations of processed meat and unprocessed red meat intake with fasting glucose and insulin concentrations; and 2) the interactions of processed meat and unprocessed red meat with genetic risk score related to fasting glucose or insulin resistance on fasting glucose and insulin concentrations. Results: Processed meat was associated with higher fasting glucose, and unprocessed red meat was associated with both higher fasting glucose and fasting insulin concentrations after adjustment for potential confounders [not including body mass index (BMI)]. For every additional 50-g serving of processed meat per day, fasting glucose was 0.021 mmol/L (95% CI: 0.011, 0.030 mmol/L) higher. Every additional 100-g serving of unprocessed red meat per day was associated with a 0.037-mmol/L (95% CI: 0.023, 0.051-mmol/L) higher fasting glucose concentration and a 0.049–ln-pmol/L (95% CI: 0.035, 0.063–ln-pmol/L) higher fasting insulin concentration. After additional adjustment for BMI, observed associations were attenuated and no longer statistically significant. The association of processed meat and fasting insulin did not reach statistical significance after correction for multiple comparisons. Observed associations were not modified by genetic

  8. Technical Decision-Making with Higher Order Structure Data: Detecting Reversible Concentration-Dependent Self-Association in a Monoclonal Antibody and a Preliminary Investigation to Eliminate It.

    PubMed

    Wei, Julie Y; Bou-Assaf, George M; Houde, Damian; Weiskopf, Andrew

    2015-11-01

    Protein self-association or aggregation is a property of significant concern for biopharmaceutical products due to the potential ability of aggregates to cause adverse toxicological and immunological effects. Thus, during the development of a protein biopharmaceutical, it is important to detect and quantify the level and nature of aggregate species as early as possible in order to make well-informed decisions and to mitigate and control potential risks. Although a deeper understanding of the mechanism of aggregation (i.e., protein-protein interactions) is desirable, such detailed assessment is not always necessary from a biopharmaceutical process development point of view. In fact, the scope of characterization efforts is often focused on achieving a well-controlled process, which generates a product that reliably meets established acceptance criteria for safety and efficacy. In this brief note, we evaluated the utility of size-exclusion chromatography, dynamic light scattering, and analytical ultracentrifugation in their simplest forms, to effectively reveal and confirm the presence of concentration-dependent reversible self-association (RSA) in a monoclonal antibody in the early stages of formulation development. Using these techniques, we also initiated preliminary work aimed at reducing the occurrence of this RSA behavior by varying the pH of the formulation buffer. PMID:26308556

  9. Assessment of cadmium (Cd) concentration in arable soil in China.

    PubMed

    Zhang, Xiuying; Chen, Dongmei; Zhong, Taiyang; Zhang, Xiaomin; Cheng, Min; Li, Xinhui

    2015-04-01

    Cadmium (Cd) concentration in arable soil has drawn broad public attention due to its direct effect on Cd concentration in food. However, there have been few studies of surveying Cd accumulation on the national scale in China. This paper collected 486 studies of Cd concentrations in Chinese arable soil. The results showed that the average Cd concentration was 0.27 mg/kg, higher than its background value, indicating that Cd had been introduced into arable soil by human activity. The Cd concentrations in areas of mining and smelting, urban areas, and areas irrigated by wastewater were obviously higher than that in remote areas. Spatially, Cd concentrations were lower in the north than those in the south, and many hotspots existed throughout China due to mining and smelting activities. Most Cd in the arable soil were accumulated from external sources in all investigated provinces except Ningxia Hui Autonomous Region.

  10. Accumulation of heavy metals in the mole in Finland.

    PubMed

    Pankakoski, E; Hyvärinen, H; Jalkanen, M; Koivisto, I

    1993-01-01

    Metal concentrations (Cu, Ni, Zn, Cd, Cr, Hg, Pb and Mo) were analysed from the liver and kidneys of moles, Talpa europaea L. (Insectivora), trapped in southern Finland on both contaminated and rural areas. In rural areas the concentrations of Cd, Cu, Zn, Pb and Mo were lower in juveniles (individuals in their first summer), except for Zn in the liver, which was lower in adults. When the animals were divided into annual classes (0-6 years), Cd and Mo concentrations in the liver increased significantly with age, while concentrations of Cu, Zn and Cr tended to decrease. Female moles had higher Pb concentrations than males, especially adult females, which also had lower levels of Cu in the liver than adult males. Moles in the metropolitan area of Helsinki clearly differed from those in rural areas in that the concentrations of heavy metals in these moles were higher (especially for the most toxic metals: Cd, Pb and Hg), and their body weight was lower. The renal concentrations of Cd in most of the moles in Helsinki exceeded the threshold that has been shown to have a nephrotoxic effect in mammals. In one subsample from Helsinki, Pb and Zn concentrations in the mole liver decreased as the distance from the highway increased. Concentrations of Pb in earthworms and several heavy metals in soil also decreased similarly in the same area. Our data indicate that Pb accumulates in moles through their diet of earthworms. PMID:15091866

  11. Primary hepatocytes from mice lacking cysteine dioxygenase show increased cysteine concentrations and higher rates of metabolism of cysteine to hydrogen sulfide and thiosulfate.

    PubMed

    Jurkowska, Halina; Roman, Heather B; Hirschberger, Lawrence L; Sasakura, Kiyoshi; Nagano, Tetsuo; Hanaoka, Kenjiro; Krijt, Jakub; Stipanuk, Martha H

    2014-05-01

    The oxidation of cysteine in mammalian cells occurs by two routes: a highly regulated direct oxidation pathway in which the first step is catalyzed by cysteine dioxygenase (CDO) and by desulfhydration-oxidation pathways in which the sulfur is released in a reduced oxidation state. To assess the effect of a lack of CDO on production of hydrogen sulfide (H2S) and thiosulfate (an intermediate in the oxidation of H2S to sulfate) and to explore the roles of both cystathionine γ-lyase (CTH) and cystathionine β-synthase (CBS) in cysteine desulfhydration by liver, we investigated the metabolism of cysteine in hepatocytes isolated from Cdo1-null and wild-type mice. Hepatocytes from Cdo1-null mice produced more H2S and thiosulfate than did hepatocytes from wild-type mice. The greater flux of cysteine through the cysteine desulfhydration reactions catalyzed by CTH and CBS in hepatocytes from Cdo1-null mice appeared to be the consequence of their higher cysteine levels, which were due to the lack of CDO and hence lack of catabolism of cysteine by the cysteinesulfinate-dependent pathways. Both CBS and CTH appeared to contribute substantially to cysteine desulfhydration, with estimates of 56 % by CBS and 44 % by CTH in hepatocytes from wild-type mice, and 63 % by CBS and 37 % by CTH in hepatocytes from Cdo1-null mice.

  12. Variation in organochlorine accumulation in relation to the life history of the Japanese eel Anguilla japonica.

    PubMed

    Arai, Takaomi

    2014-03-15

    Members of the catadromous eel live in various fresh, brackish and marine habitats. Therefore, these eels can accumulate organic pollutants and are a suitable bioindicator species for determining the levels of organic contaminants within different water bodies. The ecological risk for organochlorine compounds (OCs) in Anguilla japonica with various migration patterns, such as freshwater, estuarine and marine residences, was examined to understand the specific accumulation patterns. The concentrations of HCB, ∑HCHs, ∑CHLs and ∑DDTs in the silver stage (maturing) eel were significantly higher than those in the yellow stage (immature) eel, in accordance with the higher lipid contents in the former versus the latter. The OC accumulations were clearly different among migratory types in the eel. The ecological risk of OCs increased as the freshwater residence period in the eel lengthened. The migratory histories and the lipid contents directly affected the OC accumulation in the catadromous eel species.

  13. Higher PUFA and n-3 PUFA, conjugated linoleic acid, α-tocopherol and iron, but lower iodine and selenium concentrations in organic milk: a systematic literature review and meta- and redundancy analyses.

    PubMed

    Średnicka-Tober, Dominika; Barański, Marcin; Seal, Chris J; Sanderson, Roy; Benbrook, Charles; Steinshamn, Håvard; Gromadzka-Ostrowska, Joanna; Rembiałkowska, Ewa; Skwarło-Sońta, Krystyna; Eyre, Mick; Cozzi, Giulio; Larsen, Mette Krogh; Jordon, Teresa; Niggli, Urs; Sakowski, Tomasz; Calder, Philip C; Burdge, Graham C; Sotiraki, Smaragda; Stefanakis, Alexandros; Stergiadis, Sokratis; Yolcu, Halil; Chatzidimitriou, Eleni; Butler, Gillian; Stewart, Gavin; Leifert, Carlo

    2016-03-28

    Demand for organic milk is partially driven by consumer perceptions that it is more nutritious. However, there is still considerable uncertainty over whether the use of organic production standards affects milk quality. Here we report results of meta-analyses based on 170 published studies comparing the nutrient content of organic and conventional bovine milk. There were no significant differences in total SFA and MUFA concentrations between organic and conventional milk. However, concentrations of total PUFA and n-3 PUFA were significantly higher in organic milk, by an estimated 7 (95 % CI -1, 15) % and 56 (95 % CI 38, 74) %, respectively. Concentrations of α-linolenic acid (ALA), very long-chain n-3 fatty acids (EPA+DPA+DHA) and conjugated linoleic acid were also significantly higher in organic milk, by an 69 (95 % CI 53, 84) %, 57 (95 % CI 27, 87) % and 41 (95 % CI 14, 68) %, respectively. As there were no significant differences in total n-6 PUFA and linoleic acid (LA) concentrations, the n-6:n-3 and LA:ALA ratios were lower in organic milk, by an estimated 71 (95 % CI -122, -20) % and 93 (95 % CI -116, -70) %. It is concluded that organic bovine milk has a more desirable fatty acid composition than conventional milk. Meta-analyses also showed that organic milk has significantly higher α-tocopherol and Fe, but lower I and Se concentrations. Redundancy analysis of data from a large cross-European milk quality survey indicates that the higher grazing/conserved forage intakes in organic systems were the main reason for milk composition differences.

  14. Higher PUFA and n-3 PUFA, conjugated linoleic acid, α-tocopherol and iron, but lower iodine and selenium concentrations in organic milk: a systematic literature review and meta- and redundancy analyses.

    PubMed

    Średnicka-Tober, Dominika; Barański, Marcin; Seal, Chris J; Sanderson, Roy; Benbrook, Charles; Steinshamn, Håvard; Gromadzka-Ostrowska, Joanna; Rembiałkowska, Ewa; Skwarło-Sońta, Krystyna; Eyre, Mick; Cozzi, Giulio; Larsen, Mette Krogh; Jordon, Teresa; Niggli, Urs; Sakowski, Tomasz; Calder, Philip C; Burdge, Graham C; Sotiraki, Smaragda; Stefanakis, Alexandros; Stergiadis, Sokratis; Yolcu, Halil; Chatzidimitriou, Eleni; Butler, Gillian; Stewart, Gavin; Leifert, Carlo

    2016-03-28

    Demand for organic milk is partially driven by consumer perceptions that it is more nutritious. However, there is still considerable uncertainty over whether the use of organic production standards affects milk quality. Here we report results of meta-analyses based on 170 published studies comparing the nutrient content of organic and conventional bovine milk. There were no significant differences in total SFA and MUFA concentrations between organic and conventional milk. However, concentrations of total PUFA and n-3 PUFA were significantly higher in organic milk, by an estimated 7 (95 % CI -1, 15) % and 56 (95 % CI 38, 74) %, respectively. Concentrations of α-linolenic acid (ALA), very long-chain n-3 fatty acids (EPA+DPA+DHA) and conjugated linoleic acid were also significantly higher in organic milk, by an 69 (95 % CI 53, 84) %, 57 (95 % CI 27, 87) % and 41 (95 % CI 14, 68) %, respectively. As there were no significant differences in total n-6 PUFA and linoleic acid (LA) concentrations, the n-6:n-3 and LA:ALA ratios were lower in organic milk, by an estimated 71 (95 % CI -122, -20) % and 93 (95 % CI -116, -70) %. It is concluded that organic bovine milk has a more desirable fatty acid composition than conventional milk. Meta-analyses also showed that organic milk has significantly higher α-tocopherol and Fe, but lower I and Se concentrations. Redundancy analysis of data from a large cross-European milk quality survey indicates that the higher grazing/conserved forage intakes in organic systems were the main reason for milk composition differences. PMID:26878105

  15. Effects of surrounding land use on metal accumulation in environments and submerged plants in subtropical ponds.

    PubMed

    Liu, Hui; Bu, Hongmei; Liu, Guihua; Wang, Zhixiu; Liu, Wenzhi

    2015-12-01

    Ponds are widely used as stormwater treatment facilities to retain contaminants, including metals, and to improve water quality throughout the world. However, there is still a limited understanding of the effects of surrounding land use on metal accumulation in pond environments and organisms. To address this gap, we measured the concentrations of nine metals (i.e., Al, Ba, Ca, K, Li, Mg, Na, Se, and Sr) in water, sediments, and submerged plants collected from 37 ponds with different surrounding land uses in southwestern China and assessed the metal accumulation capacity of four dominant submerged plant species. Our results showed that Al, Ca, and K concentrations in the water were above drinking water standards. In the sediments, the average concentrations of Ca and Sr were higher than the corresponding soil background values. Ceratophyllum demersum L. could accumulate more K in aboveground biomass than Myriophyllum spicatum L. and Potamogeton maackianus A. Benn. The K concentration in submerged plants was positively influenced by the corresponding metal concentration in the water and negatively influenced by water temperature. Among the nine studied metals, only the water K concentration in ponds receiving agricultural runoff was significantly higher than that for ponds receiving urban and forested runoff. This result suggests that surrounding land use types have no significant effect on metal accumulation in sediments and submerged plants in the studied ponds. A large percentage of the metals in these ponds may be derived from natural sources such as the weathering of rocks.

  16. Effects of surrounding land use on metal accumulation in environments and submerged plants in subtropical ponds.

    PubMed

    Liu, Hui; Bu, Hongmei; Liu, Guihua; Wang, Zhixiu; Liu, Wenzhi

    2015-12-01

    Ponds are widely used as stormwater treatment facilities to retain contaminants, including metals, and to improve water quality throughout the world. However, there is still a limited understanding of the effects of surrounding land use on metal accumulation in pond environments and organisms. To address this gap, we measured the concentrations of nine metals (i.e., Al, Ba, Ca, K, Li, Mg, Na, Se, and Sr) in water, sediments, and submerged plants collected from 37 ponds with different surrounding land uses in southwestern China and assessed the metal accumulation capacity of four dominant submerged plant species. Our results showed that Al, Ca, and K concentrations in the water were above drinking water standards. In the sediments, the average concentrations of Ca and Sr were higher than the corresponding soil background values. Ceratophyllum demersum L. could accumulate more K in aboveground biomass than Myriophyllum spicatum L. and Potamogeton maackianus A. Benn. The K concentration in submerged plants was positively influenced by the corresponding metal concentration in the water and negatively influenced by water temperature. Among the nine studied metals, only the water K concentration in ponds receiving agricultural runoff was significantly higher than that for ponds receiving urban and forested runoff. This result suggests that surrounding land use types have no significant effect on metal accumulation in sediments and submerged plants in the studied ponds. A large percentage of the metals in these ponds may be derived from natural sources such as the weathering of rocks. PMID:26199006

  17. Spatially resolved analysis of variation in barley (Hordeum vulgare) grain micronutrient accumulation.

    PubMed

    Detterbeck, Amelie; Pongrac, Paula; Rensch, Stefan; Reuscher, Stefan; Pečovnik, Matic; Vavpetič, Primož; Pelicon, Primož; Holzheu, Stefan; Krämer, Ute; Clemens, Stephan

    2016-09-01

    Genetic biofortification requires knowledge on natural variation and the underlying mechanisms of micronutrient accumulation. We therefore studied diversity in grain micronutrient concentrations and spatial distribution in barley (Hordeum vulgare), a genetically tractable model cereal and an important crop with widespread cultivation. We assembled a diverse collection of barley cultivars and landraces and analysed grain micronutrient profiles in genebank material and after three independent cultivations. Lines with contrasting grain zinc (Zn) accumulation were selected for in-depth analysis of micronutrient distribution within the grain by micro-proton-induced X-ray emission (μ-PIXE). Also, we addressed association with grain cadmium (Cd) accumulation. The analysis of > 120 lines revealed substantial variation, especially in grain Zn concentrations. A large fraction of this variation is due to genetic differences. Grain dissection and μ-PIXE analysis of contrasting lines showed that differences in grain Zn accumulation apply to all parts of the grain including the endosperm. Cd concentrations exceeded the Codex Alimentarius threshold in most of the representative barley lines after cultivation in a Cd-contaminated agricultural soil. Two important conclusions for biofortification are: first, high-Zn grains contain more Zn also in the consumed parts of the grain; and second, higher micronutrient concentrations are strongly associated with higher Cd accumulation. PMID:27125321

  18. Accumulation of heavy metals in crayfish and fish from selected Czech reservoirs.

    PubMed

    Kuklina, Iryna; Kouba, Antonín; Buřič, Miloš; Horká, Ivona; Duriš, Zdeněk; Kozák, Pavel

    2014-01-01

    To evaluate the accumulation of aluminium, cadmium, chromium, copper, lead, mercury, nickel, and zinc in crayfish and fish organ tissues, specimens from three drinking water reservoirs (Boskovice, Landštejn, and Nová Říše) and one contaminated site (Darkovské moře) in the Czech Republic were examined. Crayfish hepatopancreas was confirmed to be the primary accumulating site for the majority of metals (Cu > Zn > Ni > Cd > Cr), while Hg and Cr were concentrated in abdominal muscle, and Al and Pb were concentrated in gill. Metals found in Nová Říše specimens included Cu > Zn > Ni and those found in Boskovice included Zn > Hg > Cr. Cd concentrations were observed only in Landštejn specimens, while contaminated Darkovské moře specimens showed the highest levels of accumulation (Cu > Al > Zn > Pb). The majority of evaluated metals were found in higher concentrations in crayfish: Cu > Al > Zn > Ni > Cr > Cd > Pb, with Hg being the only metal accumulating higher in fish. Due to accumulation similarities of Al in crayfish and fish gill, differences of Hg in muscle, and features noted for the remaining metals in examined tissues, biomonitoring should incorporate both crayfish and fish to produce more relevant water quality surveys.

  19. Spatially resolved analysis of variation in barley (Hordeum vulgare) grain micronutrient accumulation.

    PubMed

    Detterbeck, Amelie; Pongrac, Paula; Rensch, Stefan; Reuscher, Stefan; Pečovnik, Matic; Vavpetič, Primož; Pelicon, Primož; Holzheu, Stefan; Krämer, Ute; Clemens, Stephan

    2016-09-01

    Genetic biofortification requires knowledge on natural variation and the underlying mechanisms of micronutrient accumulation. We therefore studied diversity in grain micronutrient concentrations and spatial distribution in barley (Hordeum vulgare), a genetically tractable model cereal and an important crop with widespread cultivation. We assembled a diverse collection of barley cultivars and landraces and analysed grain micronutrient profiles in genebank material and after three independent cultivations. Lines with contrasting grain zinc (Zn) accumulation were selected for in-depth analysis of micronutrient distribution within the grain by micro-proton-induced X-ray emission (μ-PIXE). Also, we addressed association with grain cadmium (Cd) accumulation. The analysis of > 120 lines revealed substantial variation, especially in grain Zn concentrations. A large fraction of this variation is due to genetic differences. Grain dissection and μ-PIXE analysis of contrasting lines showed that differences in grain Zn accumulation apply to all parts of the grain including the endosperm. Cd concentrations exceeded the Codex Alimentarius threshold in most of the representative barley lines after cultivation in a Cd-contaminated agricultural soil. Two important conclusions for biofortification are: first, high-Zn grains contain more Zn also in the consumed parts of the grain; and second, higher micronutrient concentrations are strongly associated with higher Cd accumulation.

  20. Accumulation of Heavy Metals in Crayfish and Fish from Selected Czech Reservoirs

    PubMed Central

    Kuklina, Iryna; Kouba, Antonín; Buřič, Miloš; Horká, Ivona; Ďuriš, Zdeněk; Kozák, Pavel

    2014-01-01

    To evaluate the accumulation of aluminium, cadmium, chromium, copper, lead, mercury, nickel, and zinc in crayfish and fish organ tissues, specimens from three drinking water reservoirs (Boskovice, Landštejn, and Nová Říše) and one contaminated site (Darkovské moře) in the Czech Republic were examined. Crayfish hepatopancreas was confirmed to be the primary accumulating site for the majority of metals (Cu > Zn > Ni > Cd > Cr), while Hg and Cr were concentrated in abdominal muscle, and Al and Pb were concentrated in gill. Metals found in Nová Říše specimens included Cu > Zn > Ni and those found in Boskovice included Zn > Hg > Cr. Cd concentrations were observed only in Landštejn specimens, while contaminated Darkovské moře specimens showed the highest levels of accumulation (Cu > Al > Zn > Pb). The majority of evaluated metals were found in higher concentrations in crayfish: Cu > Al > Zn > Ni > Cr > Cd > Pb, with Hg being the only metal accumulating higher in fish. Due to accumulation similarities of Al in crayfish and fish gill, differences of Hg in muscle, and features noted for the remaining metals in examined tissues, biomonitoring should incorporate both crayfish and fish to produce more relevant water quality surveys. PMID:24738051

  1. Accumulation and chemical states of radiocesium by fungus Saccharomyces cerevisiae

    NASA Astrophysics Data System (ADS)

    Ohnuki, Toshihiko; Sakamoto, Fuminori; Kozai, Naofumi; Yamasaki, Shinya; Yu, Qianqian

    2014-05-01

    mineral for 137Cs in the medium solution. The concentration of 137Cs in the cells lowered in the medium containing higher mineral content. These results indicate that radiocesium was competively accumulated in the cells with minerals in the soil. Higher concentration of stable Cs was accumulated in the cells in the metabolically active condition than in the resting cells condition. XAFS analyses showed that the k3-weighted extended-XAFS functions and the radial structural function of Cs accumulated by the cells in the metabolically active condition were similar to those in the resting condition, indicating that chemical states of the accumulated Cs were nearly the same between both conditions. These results indicate that the fungus accumulates radiocesium by competitively with minerals in the soils, and performs higher retardation of the migration of Cs in the metabolically active condition than the resting one. A part of this study is the results of "Multidisciplinary investigation on radiocesium fate and transport for safety assessment for interim storage and disposal of heterogeneous waste" carried out under the Initiatives for Atomic Energy Basic and Generic Strategic Research by the Ministry of Education, Culture, Sports, Science and Technology of Japan.

  2. Metal accumulation by wood-decaying fungi

    SciTech Connect

    Tyler, G.

    1982-01-01

    Metal concentrations (Na, K, Rb, Mg, Ca, Sr, Mn, Fe, Cu, Zn, Cd, Al, and Pb) in the sporophores of ten wood-decaying macromycete species were related to concentrations in the wood substrates. Manganese, Sr, Ca, and Pb were usually excluded by the fungi; K, Rb, and to a lower degree, Cd, Fe, Zn, Cu, Mg and Na were accumulated. Accumulation ratios are compared with similar ratios for soil and litter inhabiting species previously studied.

  3. Accumulation of sediment-associated viruses in shellfish

    SciTech Connect

    Landry, E.F.; Vaughn, J.M.; Vicale, T.J.; Mann, R.

    1983-01-01

    The present study focused on the importance of contaminated sediments in shellfish accumulation of human viruses. Epifaunal (Crassostrea virginica) and infanual (Mercenaria mercenaria) shellfish, placed on or in cores, were exposed to either resuspended or undisturbed sediments containing bound poliovirus type 1 (LSc 2ab). Consistent bioaccumulation by oysters (four of five trials) was only noted when sediment-bound viruses occurred in the water column. Virus accumulation was observed in a single instance where sediments remained in an undisturbed state. While the incidence of bioaccumulation was higher with resuspended rather than undisturbed contaminated sediment, the actual concentration of accumulated viruses was not significantly different from the accumulation of viruses from oysters residing on uninoculated sediments. When clams were exposed to undisturbed, virus-contaminated sediments, two of five shellfish pools yielded viral isolates. Bioaccumulation of undisturbed sediments by these bivalves was considered marginal when related to the concentration of virus in contaminated sediments; they would only represent a significant threat when suspended in the water column. Arguments were advanced for water-column sampling in the region of the water-sediment interface to provide an accurate determination of the virological quality of shellfish harvesting waters.

  4. Proline accumulation in baker's yeast enhances high-sucrose stress tolerance and fermentation ability in sweet dough.

    PubMed

    Sasano, Yu; Haitani, Yutaka; Ohtsu, Iwao; Shima, Jun; Takagi, Hiroshi

    2012-01-01

    During bread-making processes, yeast cells are exposed to various baking-associated stresses. High-sucrose concentrations exert severe osmotic stress that seriously damages cellular components by generation of reactive oxygen species (ROS). Previously, we found that the accumulation of proline conferred freeze-thaw stress tolerance and the baker's yeast strain that accumulated proline retained higher-level fermentation abilities in frozen doughs than the wild-type strain. In this study, we constructed self-cloning diploid baker's yeast strains that accumulate proline. These resultant strains showed higher cell viability and lower intracellular oxidation levels than that observed in the wild-type strain under high-sucrose stress condition. Proline accumulation also enhanced the fermentation ability in high-sucrose-containing dough. These results demonstrate the usefulness of proline-accumulating baker's yeast for sweet dough baking. PMID:22041027

  5. Susceptibility of riparian wetland plants to perfluorooctanoic acid (PFOA) accumulation.

    PubMed

    Mudumbi, J B N; Ntwampe, S K O; Muganza, M; Okonkwo, J O

    2014-01-01

    As plants have been shown to accumulate organic compounds from contaminated sediments, there is a potential for long-lasting ecological impact as a result of contaminant accumulation in riparian areas of wetlands, particularly the accumulation of non-biodegradable contaminants such as perfluorooctanoic acid (PFOA). In this study, commonly found riparian wetland plants including reeds, i.e., Xanthium strumarium, Phragmites australis, Schoenoplectus corymbosus, Ruppia maritime; Populus canescens, Polygonum salicifolium, Cyperus congestus; Persicaria amphibian, Ficus carica, Artemisia schmidtiana, Eichhornia crassipes, were studied to determine their susceptibility to PFOA accumulation from PFOA contaminated riparian sediment with a known PFOA concentration, using liquid chromatography/tandem mass spectrometry (LC/MS/MS). The bioconcentration factor (BCF) indicated that the plants affinity to PFOA accumulation was; E. crassipes, > P. sali-cifolium, > C. congestus, > P. x canescens, > P. amphibian, > F. carica, > A. schmidtiana, > X. strumarium,> P. australis, > R. maritime, > S. corymbosus. The concentration of PFOA in the plants and/or reeds was in the range 11.7 to 38 ng/g, with a BCF range of 0.05 to 0.37. The highest BCF was observed in sediment for which its core water had a high salinity, total organic carbon and a pH which was near neutral. As the studied plants had a higher affinity for PFOA, the resultant effect is that riparian plants such as E. crassipes, X. strumarium, and P. salicifolium, typified by a fibrous rooting system, which grow closer to the water edge, exacerbate the accumulation of PFOA in riparian wetlands.

  6. Susceptibility of riparian wetland plants to perfluorooctanoic acid (PFOA) accumulation.

    PubMed

    Mudumbi, J B N; Ntwampe, S K O; Muganza, M; Okonkwo, J O

    2014-01-01

    As plants have been shown to accumulate organic compounds from contaminated sediments, there is a potential for long-lasting ecological impact as a result of contaminant accumulation in riparian areas of wetlands, particularly the accumulation of non-biodegradable contaminants such as perfluorooctanoic acid (PFOA). In this study, commonly found riparian wetland plants including reeds, i.e., Xanthium strumarium, Phragmites australis, Schoenoplectus corymbosus, Ruppia maritime; Populus canescens, Polygonum salicifolium, Cyperus congestus; Persicaria amphibian, Ficus carica, Artemisia schmidtiana, Eichhornia crassipes, were studied to determine their susceptibility to PFOA accumulation from PFOA contaminated riparian sediment with a known PFOA concentration, using liquid chromatography/tandem mass spectrometry (LC/MS/MS). The bioconcentration factor (BCF) indicated that the plants affinity to PFOA accumulation was; E. crassipes, > P. sali-cifolium, > C. congestus, > P. x canescens, > P. amphibian, > F. carica, > A. schmidtiana, > X. strumarium,> P. australis, > R. maritime, > S. corymbosus. The concentration of PFOA in the plants and/or reeds was in the range 11.7 to 38 ng/g, with a BCF range of 0.05 to 0.37. The highest BCF was observed in sediment for which its core water had a high salinity, total organic carbon and a pH which was near neutral. As the studied plants had a higher affinity for PFOA, the resultant effect is that riparian plants such as E. crassipes, X. strumarium, and P. salicifolium, typified by a fibrous rooting system, which grow closer to the water edge, exacerbate the accumulation of PFOA in riparian wetlands. PMID:24933893

  7. Mercury accumulation in sea lamprey (Petromyzon marinus) from Lake Huron

    USGS Publications Warehouse

    Madenjian, Charles P.; Johnson, Nicholas S.; Siefkes, Michael J.; Dettmers, John M.; Blum, Joel D.; Johnson, Marcus W.

    2014-01-01

    We determined whole-fish total mercury (Hg) concentrations of 40 male and 40 female adult sea lampreys (Petromyzon marinus) captured in the Cheboygan River, a tributary to Lake Huron, during May 2011. In addition, bioenergetics modeling was used to explore the effects of sex-related differences in activity and resting (standard) metabolic rate (SMR) on mercury accumulation. The grand mean for Hg concentrations was 519 ng/g (standard error of the mean = 46 ng/g). On average, males were 16% higher in Hg concentration than females. Bioenergetics modeling results indicated that 14% higher activity and SMR in males would account for this observed sex difference in Hg concentrations. We concluded that the higher Hg concentration in males was most likely due to higher rate of energy expenditure in males, stemming from greater activity and SMR. Our findings have implications for estimating the effects of sea lamprey populations on mercury cycling within ecosystems, as well as for the proposed opening of sea lamprey fisheries. Eventually, our results may prove useful in improving control of sea lamprey, a pest responsible for substantial damage to fisheries in lakes where it is not native.

  8. Accumulation of airborne elements from vehicles in transplanted lichens in urban sites

    SciTech Connect

    Garty, J.; Kauppi, M.; Kauppi, A.

    1996-03-01

    The objective of the current study is to compare the short-term accumulation capacity of two epiphytic lichens characterized by a different type of thallus. The lichens Hypogynmia physodes (L.) Nyl. and Usnea hirta (L.) Weber em. Mot. were transplanted either to the vicinity of streets of low volume and slow traffic or to the vicinity of a highway in the city of Oulu, N. Finland, for a period of 45 d. Eleven elements were analyzed before and after transplantation. The two lichen species were found to possess a similar accumulating capacity for K and Mn. Hypogynmia physodes manifests a higher accumulating capacity than U. hirta for Na, Fe, and Cu. whereas the more sensitive lichen U. hirta exhibits a higher accumulating capacity for Mg, despite a higher primary concentration of these elements in the thallus of H. physodes. Our findings show a relative high concentration of K, Fe, Mg, Zn, Mn, Pb, and Cu in thalli of H. physodes and Mg, Zn, Pb, Cu, and Cd in U. hirta in material transplanted to streets of low volume and slow traffic, over and above the concentration found in thalli retrieved form the vicinity of the highway. This may be explained by the higher rate of abrasion of car engines running idle near traffic lights and by the lesser ventilation near the close-clustered streets of the inner city. 65 refs., 8 tabs.

  9. Sugar Accumulation in Sugarcane

    PubMed Central

    Gayler, K. R.; Glasziou, K. T.

    1972-01-01

    The rate-limiting reaction for glucose uptake in storage tissue of sugarcane, Saccharum officinarum L., appears to be the movement of glucose across the boundary between the free space and the metabolic compartments. The mechanism for uptake of glucose across this boundary has been studied using 3-O-methyl glucose, an analogue of glucose which is not metabolized by sugar-cane tissue. This analogue is taken up by sugarcane storage tissue at a similar rate to glucose. Its rate of uptake follows Michaelis-Menten kinetics, Km = 1.9 mm, and it is competitively inhibited by glucose, Ki = 2 to 3 mm. Glucose uptake is similarly inhibited by 3-O-methyl glucose. Uptake of 3-O-methyl glucose is energy-dependent and does not appear to be the result of counterflow of glucose. It is concluded that glucose and 3-O-methyl glucose uptake across the boundary between the free space and the metabolic compartment in this tissue is mediated by an energy-dependent carrier system capable of accumulating the sugars against a concentration gradient. PMID:16658002

  10. Metal accumulation in wild-caught opossum.

    PubMed

    Lockhart, J Mitchell; Siddiqui, Samreen; Loughry, W J; Bielmyer-Fraser, Gretchen K

    2016-06-01

    The Virginia opossum (Didelphis virginiana) is widespread in the USA, ranging south through Latin America. The ecology of opossums is such that they are in frequent contact with soils, suggesting that they may function as a valuable bioindicator for chemical contamination in terrestrial environments. Surprisingly, there have been virtually no toxicology studies on opossums. Here, we provide the first analysis of metal contaminants in opossum liver tissues. Liver samples were obtained from 471 opossums, collected from 2003 to 2006, at four sites in North Florida and South Georgia, USA, and concentrations of copper, lead, nickel, selenium, and zinc were measured. We found little evidence of age differences in the concentration of any of the metals. However, there were at least some significant differences between years, males and females, and between sites for each metal, although the pattern of these differences was not always consistent across metals. Concentrations of metals in liver tissue were positively correlated with one another, primarily of each metal (except Pb) with zinc. Reference levels of metal contaminants are not available for opossums, but concentrations of Cu, Ni, Pb, and Zn in our samples were for the most part significantly higher than those reported from liver tissues of nine-banded armadillos (Dasypus novemcinctus) collected at the same sites and in the same years. Data from other small mammals studied elsewhere further indicate that metal concentrations in opossums were high, but at this time, it is not possible to determine if these elevated levels generated toxicity. The substantial temporal and spatial variation we found in metal concentrations suggests that determination of baseline levels for opossums may not be straightforward. Nonetheless, this is the first study quantifying metal accumulation in the livers of Didelphis virginiana and, as such, provides an important starting point for future research. PMID:27138002

  11. Metal accumulation in wild-caught opossum.

    PubMed

    Lockhart, J Mitchell; Siddiqui, Samreen; Loughry, W J; Bielmyer-Fraser, Gretchen K

    2016-06-01

    The Virginia opossum (Didelphis virginiana) is widespread in the USA, ranging south through Latin America. The ecology of opossums is such that they are in frequent contact with soils, suggesting that they may function as a valuable bioindicator for chemical contamination in terrestrial environments. Surprisingly, there have been virtually no toxicology studies on opossums. Here, we provide the first analysis of metal contaminants in opossum liver tissues. Liver samples were obtained from 471 opossums, collected from 2003 to 2006, at four sites in North Florida and South Georgia, USA, and concentrations of copper, lead, nickel, selenium, and zinc were measured. We found little evidence of age differences in the concentration of any of the metals. However, there were at least some significant differences between years, males and females, and between sites for each metal, although the pattern of these differences was not always consistent across metals. Concentrations of metals in liver tissue were positively correlated with one another, primarily of each metal (except Pb) with zinc. Reference levels of metal contaminants are not available for opossums, but concentrations of Cu, Ni, Pb, and Zn in our samples were for the most part significantly higher than those reported from liver tissues of nine-banded armadillos (Dasypus novemcinctus) collected at the same sites and in the same years. Data from other small mammals studied elsewhere further indicate that metal concentrations in opossums were high, but at this time, it is not possible to determine if these elevated levels generated toxicity. The substantial temporal and spatial variation we found in metal concentrations suggests that determination of baseline levels for opossums may not be straightforward. Nonetheless, this is the first study quantifying metal accumulation in the livers of Didelphis virginiana and, as such, provides an important starting point for future research.

  12. Accumulation and effects of metal mixtures in two seaweed species.

    PubMed

    Jarvis, Tayler A; Bielmyer-Fraser, Gretchen K

    2015-05-01

    Metal pollution, due to various anthropogenic sources, may pose a threat to marine ecosystems. Metals can be introduced into food chains via bioaccumulation in primary producers, and may potentially lead to toxic effects. Macroalgae are used as food by a wide variety of organisms, and are therefore extremely important in aquatic systems. This study investigated the accumulation and effects of metals in two macroalgae species. The green seaweed, Ulva lactuca and the red seaweed, Agardhiella subulata were each concurrently exposed to five metals (Cu, Ni, Pb, Cd, and Zn) and U. lactuca was also exposed to each metal individually for 48 h. Metal accumulation in the seaweed was measured, and various photosynthetic parameters were assessed, using imaging pulse amplitude modulated (PAM) fluorometry. Increased metal accumulation occurred in both seaweed species after 48 h exposure to metal mixtures and each metal individually. The distribution of metals in both seaweed species changed with increasing metal exposure concentrations, resulting in higher proportions of Cu and Zn in the metal-exposed groups, as compared to respective controls. Further, U. lactuca accumulated higher concentrations of metals when exposed to each metal individually rather than in metal mixtures, suggesting interactions among metals for uptake and/or bioaccumulation. Significant impairment of photosynthetic parameters in U. lactuca was observed after exposure to 100 and 1000 μg/L metal mixtures, as well as 100 μg/L of either Cd or Cu. These results demonstrate metal bioaccumulation and toxic effects in important primary producers, and may have implications for higher trophic levels.

  13. Possible routes for lead accumulation in feral pigeons (Columba livia).

    PubMed

    Nam, Dong-Ha; Lee, Doo-Pyo

    2006-10-01

    This study examined possible routes for lead (Pb) accumulation in resident pigeons collected from rural, urban, and four industrial sites in Korea. The accumulation pattern of Pb was comparable to the study sites. The highest Pb concentration was found in the bone, followed by kidney, liver, and lung of pigeons. Highest Pb residues in bones were found in urban (Seoul), and two industrial complex areas (Busan and Ulsan), which were about 15 times higher than rural area (Duckjuk island), and followed by Ansan and Yochon industrial areas. Regional Pb variations in liver, kidney, and lung tissues were also similar pattern with the bone Pb difference. These findings indicate that Pb accumulation in tissues of pigeons may be affected by the Pb exposure in their respective habitats. Crop contents and gizzard materials were investigated as representing the ingested items. No difference of Pb concentration was observed in major foods (maize and/or wheat) of crop contents in the study sites except Busan, whereas variations of Pb levels in gizzard materials were indicative of a similar pattern with tissue Pb differences. The Pb concentration in tissues of pigeons did not correspond well to the atmospheric Pb levels. With regard to possible Pb sources, ingested items especially materials present in the gizzard are important sources for Pb contamination to pigeons because Pb-containing sources may be expected to present in roadside particles, dusts, paint chips and building flakes. However, air Pb value being low may not affect significant as the regional variations in tissues of pigeons.

  14. Intracellular accumulation of ethanol in yeast

    SciTech Connect

    Loueiro, V.; Ferreira, H.G.

    1983-09-01

    Ethanol produced in the course of a batch fermentation by Saccharomyces cerevisiae or added from the outside, affects adversely the specific rate of growth of the yeast population, its viability, its specific rate of fermentation, and the specific rates of the uptake of sugar and amino acids. The underlying mechanisms are many and include irreversible denaturation and hyperbolic noncompetitive inhibition of glycolytic enzymes, the exponential noncompetitive inhibition of glucose, maltose, and ammonium transport, the depression of the optimum and the maximum temperature for growth, the increase of the minimum temperature for growth, and the enhancement of thermal death and petite mutation. Nagodawithana and Steinkraus reported that added ethanol was less toxic for S. cerevisiae than ethanol produced by the yeast. The death rates were lower in the presence of added ethanol than those measured at similar external ethanol concentrations endogenously produced. They proposed that, due to an unbalance between the rates of production and the net outflux of ethanol, there would be an intracellular accumulation of ethanol which in turn would explain the apparently greater inhibitory potency of endogenously produced ethanol present in the medium. This hypothesis was supported by the findings of several authors who reported that the intracellular concentration of ethanol, in the course of batch fermentation, is much higher than its concentration in the extracellular medium. The present work is an attempt to clarify this matter. (Refs. 32).

  15. Accumulation of cadmium by durum wheat roots: bases for citrate-mediated exceptions to the free ion model.

    PubMed

    Berkelaar, Edward; Hale, Beverley A

    2003-05-01

    The accumulation of Cd in durum wheat (Triticum turgidum) roots from hydroponic solutions, with the proportion of total Cd (8.9-445 nM Cd) as Cd2+ varied by the addition of citrate, was determined to test the free-ion model (FIM) of metal bioavailability for higher plants. Calcium, Mg, and K were also varied. Citrate enhanced root-Cd accumulation at higher Cd2+ concentrations but not lower relative to the same Cd2+ concentrations in solutions containing 0 mM citrate. Elevating Ca2+ and Mg2+ concentrations in the citrate solution to the same as those in control solutions alleviated some of the citrate-mediated enhancement but not all. Solutions containing 66% less Ca or Mg than control but the same Cd2+ concentration and no citrate also resulted in increased root Cd. Elevated K+ did not influence Cd accumulation. Regression relationships between root-Cd accumulation and total Cd in solution were similar for the control and pooled amended solutions, whereas they were different for root-Cd accumulation and solution Cd2+. These results contribute to the growing body of evidence that the FIM alone is likely insufficient to predict plant accumulation of metals from soils, although it may be a useful probe for the mechanistic bases of metal bioavailability.

  16. Effect of minerals on accumulation of Cs by fungus Saccaromyces cerevisiae.

    PubMed

    Ohnuki, Toshihiko; Sakamoto, Fuminori; Yamasaki, Shinya; Kozai, Naofumi; Shiotsu, Hiroyuki; Utsunomiya, Satoshi; Watanabe, Naoko; Kozaki, Tamotsu

    2015-06-01

    The accumulation of Cs by unicellular fungus of Saccharomyces cerevisiae in the presence of minerals has been studied to elucidate the role of microorganisms in the migration of radioactive Cs in the environment. Two different types of experiments were employed: experiments using stable Cs to examine the effect of a carbon source on the accumulation of Cs, and accumulation experiments of radioactive Cs from agar medium containing (137)Cs and zeolite, vermiculite, phlogopite, smectite, mica, or illite as mineral supplements. In the former type of experiments, the Cs-accumulated cells were analyzed by scanning electron microscopy equipped with energy dispersive X-ray analysis (SEM-EDS). In the latter type, the radioactivity in the yeast cells was measured by an autoradiography technique. When a carbon source was present, higher amounts of Cs accumulated in the cells than in the resting condition without a carbon source. Analyses with SEM-EDS showed that no mineral formed on the cell surface. These results indicate that the yeast cells accumulate Cs by adsorption on the cell surface and intracellular accumulation. In the presence of minerals in the agar medium, the radioactivity in the yeast cells was in the order of mica > smectite, illite > vermiculite, phlogopite, zeolite. This order is inversely correlated to the ratio of the concentration of radioactive Cs between the minerals and the medium solution. These results strongly suggest that the yeast accumulates radioactive Cs competitively with minerals.

  17. Effect of minerals on accumulation of Cs by fungus Saccaromyces cerevisiae.

    PubMed

    Ohnuki, Toshihiko; Sakamoto, Fuminori; Yamasaki, Shinya; Kozai, Naofumi; Shiotsu, Hiroyuki; Utsunomiya, Satoshi; Watanabe, Naoko; Kozaki, Tamotsu

    2015-06-01

    The accumulation of Cs by unicellular fungus of Saccharomyces cerevisiae in the presence of minerals has been studied to elucidate the role of microorganisms in the migration of radioactive Cs in the environment. Two different types of experiments were employed: experiments using stable Cs to examine the effect of a carbon source on the accumulation of Cs, and accumulation experiments of radioactive Cs from agar medium containing (137)Cs and zeolite, vermiculite, phlogopite, smectite, mica, or illite as mineral supplements. In the former type of experiments, the Cs-accumulated cells were analyzed by scanning electron microscopy equipped with energy dispersive X-ray analysis (SEM-EDS). In the latter type, the radioactivity in the yeast cells was measured by an autoradiography technique. When a carbon source was present, higher amounts of Cs accumulated in the cells than in the resting condition without a carbon source. Analyses with SEM-EDS showed that no mineral formed on the cell surface. These results indicate that the yeast cells accumulate Cs by adsorption on the cell surface and intracellular accumulation. In the presence of minerals in the agar medium, the radioactivity in the yeast cells was in the order of mica > smectite, illite > vermiculite, phlogopite, zeolite. This order is inversely correlated to the ratio of the concentration of radioactive Cs between the minerals and the medium solution. These results strongly suggest that the yeast accumulates radioactive Cs competitively with minerals. PMID:25841115

  18. Chromium accumulation by the hyperaccumulator plant Leersia hexandra Swartz.

    PubMed

    Zhang, Xue-Hong; Liu, Jie; Huang, Hai-Tao; Chen, Jun; Zhu, Yi-Nian; Wang, Dun-Qiu

    2007-04-01

    Leersia hexandra Swartz (Gramineae), which occurs in Southern China, has been found to be a new chromium hyperaccumulator by means of field survey and pot-culture experiment. The field survey showed that this species had an extraordinary accumulation capacity for chromium. The maximum Cr concentration in the dry leaf matter was 2978 mg kg(-1) on the side of a pond near an electroplating factory. The average concentration of chromium in the leaves was 18.86 times as that in the pond sediment, and 297.41 times as that in the pond water. Under conditions of the nutrient solution culture, it was found that L. hexandra had a high tolerance and accumulation capacity to Cr(III) and Cr(VI). Under 60 mg l(-1) Cr(III) and 10 mg l(-1) Cr(VI) treatment, there was no significant decrease of biomass in the leaves of L. hexandra (p>0.05). The highest bioaccumulation coefficients of the leaves for Cr(III) and Cr(VI) were 486.8 and 72.1, respectively. However, L. hexandra had a higher accumulation capacity for Cr(III) than for Cr(VI). At the Cr(III) concentration of 10 mg l(-1) in the culture solution, the concentration of chromium in leaves was 4868 mg kg(-1), while at the same Cr(VI) concentration, the concentration of chromium in leaves was only 597 mg kg(-1). These results confirmed that L. hexandra is a chromium hyperaccumulator which grows rapidly with a great tolerance to Cr and broad ecological amplitude. This species could provide a new plant resource that explores the mechanism of Cr hyperaccumulation, and has potential for usage in the phytoremediation of Cr-contaminated soil and water. PMID:17207838

  19. Higher intake of vitamin B-6 and dairy products and lower intake of green and oolong tea are independently associated with lower serum homocysteine concentration in young Japanese women.

    PubMed

    Murakami, Kentaro; Sasaki, Satoshi; Uenishi, Kazuhiro

    2013-08-01

    Little is known about the relation of modifiable dietary factors to circulating homocysteine concentrations, particularly in young adults and non-Western populations. We investigated the hypothesis that intakes of nutrients and foods are associated with serum homocysteine concentration in a group of young Japanese women. This cross-sectional study included 1050 female Japanese dietetic students aged 18 to 22 years. Dietary intake was assessed using a validated, self-administered, comprehensive diet history questionnaire. Fasting blood samples were collected, and serum homocysteine concentrations were measured. Adjustment was made for survey year, region, municipality level, current smoking, current alcohol drinking, dietary supplement use, physical activity, body mass index, energy intake, and intakes of other nutrients or foods. After adjustment for nondietary confounding factors, intakes of all B vitamins (folate, vitamin B-6, vitamin B-12, and riboflavin) were inversely associated with homocysteine concentration. However, only vitamin B-6 remained significant after further adjustment for other B vitamins. Marine-origin n-3 polyunsaturated fatty acid intake showed an inverse association, but this was not independent of intakes of B vitamins. For foods, pulses, fish and shellfish, and vegetables were independently and inversely associated with homocysteine concentration, but these associations disappeared after adjustment for intakes of other foods. Conversely, an inverse association for dairy products and a positive association for green and oolong tea remained even after adjustment for other foods. To conclude, in a group of young Japanese women, higher intake of vitamin B-6 and dairy products and lower intake of green and oolong tea were independently associated with lower serum homocysteine concentration.

  20. Cadmium re-distribution from pod and root zones and accumulation by peanut (Arachis hypogaea L.).

    PubMed

    Wang, Kairong; Song, Ningning; Zhao, Qiaoqiao; van der Zee, S E A T M

    2016-01-01

    Peanut (Arachis hypogaea L.) genotypes may differ greatly with regard to cadmium (Cd) accumulation, but the underlying mechanisms remain unclear. To determine the key factors that may contribute to Cd re-distribution and accumulation in peanut genotypes with different Cd accumulating patterns, a split-pot soil experiment was conducted with three common Chinese peanut cultivars (Fenghua-6, Huayu-20, and Huayu-23). The growth medium was separated into pod and root zones with varied Cd concentrations in each zone to determine the re-distribution of Cd after it is taken up via different routes. The peanut cultivars were divided into two groups based on Cd translocation efficiency as follows: (1) high internal Cd translocation efficiency cultivar (Fenghua-6) and (2) low internal Cd translocation efficiency cultivars (Huayu-20 and Huayu-23). Compared with Fenghua-6, low Cd translocation cultivars Huayu-20 and Huayu-23 showed higher biomass production, especially in stems and leaves, leading to dilution of metal concentrations. Results also showed that Cd concentration in roots increased significantly with increasing Cd concentrations in soils when Cd was applied in the root zone. However, there were no significant differences in the root Cd concentrations between different pod zone Cd treatments and the control, suggesting that root uptake, rather than pod uptake, is responsible for Cd accumulation in the roots of peanuts. Significant differences of Cd distribution were observed between pod and root zone Cd exposure treatments. The three peanut cultivars revealed higher kernel over total Cd fractions for pod than for root zone Cd exposure if only extra applied Cd was considered. This suggests that uptake through peg and pod shell might, at least partially, be responsible for the variation in Cd re-distribution and accumulation among peanut cultivars. Cd uptake by plants via two routes (i.e., via roots and via pegs and pods, respectively) and internal Cd translocation

  1. [Accumulation of polycyclic arenes in Baltic Sea algae].

    PubMed

    Veldre, I A; Itra, A R; Paal'me, L P; Kukk, Kh A

    1985-01-01

    The paper presents data on the level of benzo(a)pyrene (BP) and some other polycyclic arenes in alga and phanerogam specimens from different gulfs of the Baltic Sea. Algae were shown to absorb BP from sea water. The mean concentration of BP in sea water was under 0.004 microgram/1, while in algae it ranged 0.1-21.2 micrograms/kg dry weight. Algae accumulate BP to a higher degree than phanerogams. The highest concentrations of BP were found in algae Enteromorpha while the lowest ones in Furcellaria. In annual green algae, BP level was higher in autumn, i. e. at the end of vegetation period, than in spring. Brown algae Fucus vesiculosus is recommended for monitoring polycyclic arene pollution in the area from Vormsi Island to Käsmu and green algae Cladophora or Enteromorpha in the eastern part of the Finnish Gulf.

  2. [Accumulation of polycyclic arenes in Baltic Sea algae].

    PubMed

    Veldre, I A; Itra, A R; Paal'me, L P; Kukk, Kh A

    1985-01-01

    The paper presents data on the level of benzo(a)pyrene (BP) and some other polycyclic arenes in alga and phanerogam specimens from different gulfs of the Baltic Sea. Algae were shown to absorb BP from sea water. The mean concentration of BP in sea water was under 0.004 microgram/1, while in algae it ranged 0.1-21.2 micrograms/kg dry weight. Algae accumulate BP to a higher degree than phanerogams. The highest concentrations of BP were found in algae Enteromorpha while the lowest ones in Furcellaria. In annual green algae, BP level was higher in autumn, i. e. at the end of vegetation period, than in spring. Brown algae Fucus vesiculosus is recommended for monitoring polycyclic arene pollution in the area from Vormsi Island to Käsmu and green algae Cladophora or Enteromorpha in the eastern part of the Finnish Gulf. PMID:4060672

  3. Studies on heavy metal accumulation in aquatic macrophytes from Sevan (Armenia) and Carambolim (India) lake systems.

    PubMed

    Vardanyan, Lilit G; Ingole, Baban S

    2006-02-01

    Aquatic macrophytes are unchangeable biological filters and they carry out purification of the water bodies by accumulating dissolved metals and toxins in their tissue. In view of their potential to entrap several toxic heavy metals, 45 macrophytes belonging to 8 families collected from two different physiographic locations (36 from Sevan Lake, Armenia; 9 from Carambolim Lake, Old Goa, India) were studied for estimation of 14 heavy metals. The study was aimed at understanding the importance of these macrophytes in accumulation of toxic metals and controlling the heavy metal pollution and suggesting the remedial measures, if any, for the preservation and restoration of lake ecosystem. Inductively Coupled Plasma-Atomic Emission Spectrometric (ICP-AES) analyses of these aquatic macrophytes have shown the importance of aquatic macrophytes in accumulation of heavy metals and maintaining the clarity of water bodies beside their role in trophic systems. Accumulation of most of the heavy metals was higher in root system. The representative macrophytes from two different physiographic locations show similar trends and order in accumulating different metals generally. Of the 14 metals investigated, 9 (Ca, Fe, Al, Cr, Cu, Ba, Ti, Co and Pb) showed higher rates of accumulation in the root whereas 3 (Mn, Zn and Mg) showed more accumulation in stem and 1 (Ca) showed higher accumulation in the leaves. In most of the samples Cu was accumulated more in the roots (50+/-47.15 microg/g) and less in flowers (9.52+/-3.97 microg/g). Occurrence of heavy metal was much higher in macrophytes of Sevan Lake than that of the Carambolim Lake. The accumulation of 14 elements was in order of Ca>Mg>Fe>Al>Mn>Ba>Zn>Ti>Cu>Cr>Co>Ni>Pb>Cd. The present study revealed that the aquatic macrophytes play a very significant role in removing the different metals from the ambient environments. They probably play a major role in reducing the effect of high concentration of heavy metals. Therefore, the

  4. Added versus accumulated sugars on color development and acrylamide formation in french-fried potato strips.

    PubMed

    Higley, Jeremy; Kim, Jong-Yea; Huber, Kerry C; Smith, Gordon

    2012-09-01

    Added (glucose addition) versus accumulated (in situ sugar development via cold-temperature storage) sugar treatments were investigated in relation to acrylamide formation within fried potato strips at standardized levels of finish-fried color (Agtron color scores ranged from 36 to 84). The added sugar treatment exhibited a relatively reduced rate of acrylamide formation and generally possessed a lower and less variable acrylamide content (61-1290 ng/g) than the accumulated sugar scheme (61-2191 ng/g). In a subsequent experiment, added fructose applied to strip surfaces via dipping prior to frying favored acrylamide formation over color development relative to added glucose, for which the reverse trend was observed. Thus, where acrylamide differences were noted between added and accumulated sugar treatments (given equivalent Agtron color scores), this result was likely aided by the relative higher fructose content in strips of the accumulated sugar scheme rather than simply a greater relative concentration of total reducing sugars. PMID:22881236

  5. Bromine accumulation in acidic black colluvial soils

    NASA Astrophysics Data System (ADS)

    Cortizas, Antonio Martínez; Vázquez, Cruz Ferro; Kaal, Joeri; Biester, Harald; Casais, Manuela Costa; Rodríguez, Teresa Taboada; Lado, Luis Rodríguez

    2016-02-01

    Recent investigations showed that bromine is incorporated to soil organic matter (SOM), its content increasing with humification. But few research was done on its long-term accumulation and the role played by pedogenetic processes, as those involved in organic matter stabilization. We investigated bromine content and distribution in four deep, acidic, organic-rich, Holocene soils from an oceanic area of Western Europe. Bromine concentrations (93-778 μg g-1) in the silt + clay (<50 μm) fraction were on average 3-times higher than those (17-250 μg g-1) in the fine earth (<2 mm), the former containing almost all bromine (90 ± 5%). Inventories were between 148 and 314 g m-2, indicating a rather large variability in a small area, and total estimated retention was low (6-16%). The degree of SOM bromination, expressed as the Br/C molar ratio, varied between 0.03 and 1.20 mmol Br/mol C. The ratio was highly correlated (n = 23, r2 0.88, p < 0.01) with the age of the SOM for the last ∼12 ka. Partial least squares modeling indicates that bromine concentration depends on the amount of organic matter stabilized as aluminium-OM associations, and to a lesser extent on soil acidity (pH) and iron-OM associations. Thus, at scales of thousands of years, bromine accumulation in acidic soils is linked to the pool of metal-clay-stabilized organic matter.

  6. Cadmium toxicity in Maize (Zea mays L.): consequences on antioxidative systems, reactive oxygen species and cadmium accumulation.

    PubMed

    Anjum, Shakeel Ahmad; Tanveer, Mohsin; Hussain, Saddam; Bao, Mingchen; Wang, Longchang; Khan, Imran; Ullah, Ehsan; Tung, Shahbaz Atta; Samad, Rana Abdul; Shahzad, Babar

    2015-11-01

    Increased cadmium (Cd) accumulation in soils has led to tremendous environmental problems, with pronounced effects on agricultural productivity. Present study investigated the effects of Cd stress imposed at various concentrations (0, 75, 150, 225, 300, 375 μM) on antioxidant activities, reactive oxygen species (ROS), Cd accumulation, and productivity of two maize (Zea mays L.) cultivars viz., Run Nong 35 and Wan Dan 13. Considerable variations in Cd accumulation and in behavior of antioxidants and ROS were observed under Cd stress in both maize cultivars, and such variations governed by Cd were concentration dependent. Exposure of plant to Cd stress considerably increased Cd concentration in all plant parts particularly in roots. Wan Dan 13 accumulated relatively higher Cd in root, stem, and leaves than Run Nong 35; however, in seeds, Run Nong 35 recorded higher Cd accumulation. All the Cd toxicity levels starting from 75 μM enhanced H2O2 and MDA concentrations and triggered electrolyte leakage in leaves of both cultivars, and such an increment was more in Run Nong 35. The ROS were scavenged by the enhanced activities of superoxide dismutase, peroxidase, catalase, ascorbate peroxidase, and glutathione peroxidase in response to Cd stress, and these antioxidant activities were higher in Wan Dan 13 compared with Run Nong 35 at all Cd toxicity levels. The grain yield of maize was considerably reduced particularly for Run Nong 35 under different Cd toxicity levels as compared with control. The Wan Dan 13 was better able to alleviate Cd-induced oxidative damage which was attributed to more Cd accumulation in roots and higher antioxidant activities in this cultivar, suggesting that manipulation of these antioxidants and enhancing Cd accumulation in roots may lead to improvement in Cd stress tolerance.

  7. Water management practices affect arsenic and cadmium accumulation in rice grains.

    PubMed

    Sun, Liming; Zheng, Manman; Liu, Hongyan; Peng, Shaobing; Huang, Jianliang; Cui, Kehui; Nie, Lixiao

    2014-01-01

    Cadmium (Cd) and arsenic (As) accumulation in rice grains is a great threat to its productivity, grain quality, and thus human health. Pot and field studies were carried out to unravel the effect of different water management practices (aerobic, aerobic-flooded, and flooded) on Cd and As accumulation in rice grains of two different varieties. In pot experiment, Cd or As was also added into the soil as treatment. Pots without Cd or As addition were maintained as control. Results indicated that water management practices significantly influenced the Cd and As concentration in rice grains and aerobic cultivation of rice furnished less As concentration in its grains. Nonetheless, Cd concentration in this treatment was higher than the grains of flooded rice. Likewise, in field study, aerobic and flooded rice cultivation recorded higher Cd and As concentration, respectively. However, growing of rice in aerobic-flooded conditions decreased the Cd concentration by 9.38 times on average basis as compared to aerobic rice. Furthermore, this treatment showed 28% less As concentration than that recorded in flooded rice cultivation. The results suggested that aerobic-flooded cultivation may be a promising strategy to reduce the Cd and As accumulations in rice grains simultaneously. PMID:25013859

  8. Water Management Practices Affect Arsenic and Cadmium Accumulation in Rice Grains

    PubMed Central

    Liu, Hongyan; Peng, Shaobing; Huang, Jianliang; Cui, Kehui

    2014-01-01

    Cadmium (Cd) and arsenic (As) accumulation in rice grains is a great threat to its productivity, grain quality, and thus human health. Pot and field studies were carried out to unravel the effect of different water management practices (aerobic, aerobic-flooded, and flooded) on Cd and As accumulation in rice grains of two different varieties. In pot experiment, Cd or As was also added into the soil as treatment. Pots without Cd or As addition were maintained as control. Results indicated that water management practices significantly influenced the Cd and As concentration in rice grains and aerobic cultivation of rice furnished less As concentration in its grains. Nonetheless, Cd concentration in this treatment was higher than the grains of flooded rice. Likewise, in field study, aerobic and flooded rice cultivation recorded higher Cd and As concentration, respectively. However, growing of rice in aerobic-flooded conditions decreased the Cd concentration by 9.38 times on average basis as compared to aerobic rice. Furthermore, this treatment showed 28% less As concentration than that recorded in flooded rice cultivation. The results suggested that aerobic-flooded cultivation may be a promising strategy to reduce the Cd and As accumulations in rice grains simultaneously. PMID:25013859

  9. Accumulation, Speciation And Cellular Localization of Copper in 'Sesbania Drummondii'

    SciTech Connect

    Sahi, S.V.; Israr, M.; Srivastava, A.K.; Gardea-Torresdey, J.L.; Parsons, J.G.; /Western Kentucky U. /Texas U., El Paso

    2007-07-12

    Growth, accumulation and intracellular speciation and distribution of copper (Cu) in Sesbania drummondii was studied using scanning-electron microscopy (SEM), X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS). The growth of seedlings was assessed in terms of biomass accumulation. The growth of the seedling was enhanced by 73.5% at a low Cu concentration (50 mg l{sup -1}) compared to the control treatment. Additionally, seedling growth was inhibited by 18% at 300 mg l{sup -1} Cu with respect to the control. Copper concentration in roots and shoots was increased with increasing Cu concentration in the growth solution. The accumulation of Cu was found to be higher in roots than in the shoots. At a concentration of 300 mg l{sup -1} Cu, the roots accumulated 27,440 mg Cu kg{sup -1} dry weight (dw) while shoots accumulated 1282 mg Cu kg{sup -1} dw. Seedlings were assessed for photosynthetic activity by measuring chlorophyll a fluorescence parameters: Fv/Fm and Fv/F0 values. Photosynthetic integrity was not affected by any of the Cu treatments. The X-ray absorption spectroscopic (XAS) studies showed that Cu was predominantly present as Cu(II) in Sesbania tissue. In addition, from the XAS studies it was shown that the Cu exists in a mixture of different coordination states consisting of Cu bound to sugars and small organic acids with some possible precipitated copper oxide. From the EXAFS studies, the coordination of Cu was determined to have four equatorial oxygen(nitrogen) ligands at 1.96 angstroms and two axial oxygen ligands at 2.31 angstroms. Scanning-electron microscopy studies revealed the distribution of Cu within the seedlings tissues, predominantly accumulated in the cortical and vascular (xylem) regions of root tissues. In the stem, most of the Cu was found within the xylem tissue. However, the deposition of Cu within the leaf tissues was in the parenchyma. The present study demonstrates the mechanisms employed by

  10. Microbial accumulation of uranium, radium, and cesium

    SciTech Connect

    Strandberg, G.W.; Shumate, S.E. II; Parrott, J.R. Jr.; North, S.E.

    1981-05-01

    Diverse microbial species varied considerably in their ability to accumulate uranium, cesium, and radium. Mechanistic differences in uranium uptake by Saccharomyces cerevisiae and Pseudomonas aeruginosa were indicated. S. serevisiae exhibited a slow (hours) surface accumulation of uranium which was subject to environmental factors, while P. aeruginosa accumulated uranium rapidly (minutes) as dense intracellular deposits and did not appear to be affected by environmental parameters. Metabolism was not required for uranium uptake by either organism. Cesium and radium were concentrated to a considerably lesser extent than uranium by the several species tested.

  11. Accumulation and phytotoxicity of engineered nanoparticles to Cucurbita pepo.

    PubMed

    Hawthorne, Joseph; Musante, Craig; Sinha, Saion K; White, Jason C

    2012-04-01

    The effect of bulk and engineered nanoparticle (NP) Ag, Au, Cu, Si, and C at 250 and 750 mg/L on zucchini biomass, transpiration, and element content was determined. The pH of bulk and NP solutions prior to plant growth frequently differed. Nanoparticle Cu solution pH was significantly higher than bulk Cu, whereas for Ag and C, the NPs had significantly lower pH. Plants were unaffected by Au, regardless of particle size or concentration. NP Ag reduced plant biomass and transpiration by 49-91% compared to equivalent bulk Ag. NP Si at 750 mg/L reduced plant growth and transpiration by 30-51% relative to bulk Si. Bulk and NP Cu were phytotoxic but much of the effect was alleviated by humic acid. The shoot Ag and Cu content did not differ based on particle size or concentration. The accumulation of bulk Au was greater than the NP, but humic acid increased the accumulation of NP and bulk Au by 5.6-fold and 80%, respectively. The uptake of NP Si was 5.6-6.5-fold greater than observed with the bulk element. These findings show that the NPs may have unique phytotoxicity or accumulation patterns and that solution properties can significantly impact particle fate and effects. PMID:22567722

  12. Accumulation and phytotoxicity of engineered nanoparticles to Cucurbita pepo.

    PubMed

    Hawthorne, Joseph; Musante, Craig; Sinha, Saion K; White, Jason C

    2012-04-01

    The effect of bulk and engineered nanoparticle (NP) Ag, Au, Cu, Si, and C at 250 and 750 mg/L on zucchini biomass, transpiration, and element content was determined. The pH of bulk and NP solutions prior to plant growth frequently differed. Nanoparticle Cu solution pH was significantly higher than bulk Cu, whereas for Ag and C, the NPs had significantly lower pH. Plants were unaffected by Au, regardless of particle size or concentration. NP Ag reduced plant biomass and transpiration by 49-91% compared to equivalent bulk Ag. NP Si at 750 mg/L reduced plant growth and transpiration by 30-51% relative to bulk Si. Bulk and NP Cu were phytotoxic but much of the effect was alleviated by humic acid. The shoot Ag and Cu content did not differ based on particle size or concentration. The accumulation of bulk Au was greater than the NP, but humic acid increased the accumulation of NP and bulk Au by 5.6-fold and 80%, respectively. The uptake of NP Si was 5.6-6.5-fold greater than observed with the bulk element. These findings show that the NPs may have unique phytotoxicity or accumulation patterns and that solution properties can significantly impact particle fate and effects.

  13. Accumulation rates of airborne heavy metals in wetlands

    USGS Publications Warehouse

    Souch, C.J.; Filippelli, G.M.; Dollar, N.; Perkins, S.; Mastalerz, Maria

    2002-01-01

    Accumulation rates of heavy metals (Cd, Cr, Cu, Mn, Pb, and Zn) retained in wetland sediments in northwest Indiana-downwind of the Chicago-Gary-Hammond industrial area-are quantified to assess anthropogenic influences on atmospheric fluxes. Metal concentrations for 22 sediment cores are determined by ICP-AES after ashing and strong acid extraction. Relations between organic content and metal concentrations at depth are used to separate natural and anthropogenic sources. Accumulation rates over the lifetime of the wetlands (???4500 years) have averaged 0.2 (Cd), 1.4 (Cu), 1.7 (Cr), 13.4 (Mn), 4.8 (Pb), and 18.7 (Zn) mg m-2 y-1. Rates for the last 100 years have increased on average by factors of 6 (Cd), 8 (Cu), 10 (Mn), 15 (Pb), and 30 (Zn), remaining effectively constant for Cr. Where the wetlands have been drained, metals have been lost from the sediments, owing to changes in organic content and local hydrochemistry (exposure to acidic rainfall). Sediment-based accumulation rates at the undrained sites are higher, though generally consistent, with measured and modeled atmospheric fluxes documented by short-term studies conducted over the last three decades. The fraction of the total metals in the wetlands estimated to be of anthropogenic origin ranges from approximately 3% for Cr, up to approximately 35% for Pb, and 70% for Zn. This historic legacy of contamination must be considered in land management decisions, particularly when wetlands are drained.

  14. Enhanced accumulation of atropine in Atropa belladonna transformed by Rac GTPase gene isolated from Scoparia dulcis.

    PubMed

    Asano, Kyouhei; Lee, Jung-Bum; Yamamura, Yoshimi; Kurosaki, Fumiya

    2013-12-01

    Leaf tissues of Atropa belladonna were transformed by Sdrac2, a Rac GTPase gene, that is isolated from Scoparia dulcis, and the change in atropine concentration of the transformants was examined. Re-differentiated A. belladonna overexpressing Sdrac2 accumulated considerable concentration of atropine in the leaf tissues, whereas the leaves of plants transformed by an empty vector accumulated only a very low concentration of the compound. A. belladonna transformed by CASdrac2, a modified Sdrac2 of which translate was expected to bind guanosine triphosphate (GTP) permanently, accumulated very high concentrations of atropine (approximately 2.4-fold excess to those found in the wild-type plant in its natural habitat). In sharp contrast, the atropine concentration in transformed A. belladonna prepared with negatively modified Sdrac2, DNSdrac2, expected to bind guanosine diphosphate instead of GTP, was very low. These results suggested that Rac GTPases play an important role in the regulation of secondary metabolism in plant cells and that overexpression of the gene(s) may be capable of enhancing the production of natural products accumulated in higher plant cells. PMID:23852262

  15. Galactinol synthase enzyme activity influences raffinose family oligosaccharides (RFO) accumulation in developing chickpea (Cicer arietinum L.) seeds.

    PubMed

    Gangola, Manu P; Jaiswal, Sarita; Kannan, Udhaya; Gaur, Pooran M; Båga, Monica; Chibbar, Ravindra N

    2016-05-01

    To understand raffinose family oligosaccharides (RFO) metabolism in chickpea (Cicer arietinum L.) seeds, RFO accumulation and corresponding biosynthetic enzymes activities were determined during seed development of chickpea genotypes with contrasting RFO concentrations. RFO concentration in mature seeds was found as a facilitator rather than a regulating step of seed germination. In mature seeds, raffinose concentrations ranged from 0.38 to 0.68 and 0.75 to 0.99 g/100 g, whereas stachyose concentrations varied from 0.79 to 1.26 and 1.70 to 1.87 g/100 g indicating significant differences between low and high RFO genotypes, respectively. Chickpea genotypes with high RFO concentration accumulated higher concentrations of myo-inositol and sucrose during early seed developmental stages suggesting that initial substrate concentrations may influence RFO concentration in mature seeds. High RFO genotypes showed about two to three-fold higher activity for all RFO biosynthetic enzymes compared to those with low RFO concentrations. RFO biosynthetic enzymes activities correspond with accumulation of individual RFO during seed development.

  16. Galactinol synthase enzyme activity influences raffinose family oligosaccharides (RFO) accumulation in developing chickpea (Cicer arietinum L.) seeds.

    PubMed

    Gangola, Manu P; Jaiswal, Sarita; Kannan, Udhaya; Gaur, Pooran M; Båga, Monica; Chibbar, Ravindra N

    2016-05-01

    To understand raffinose family oligosaccharides (RFO) metabolism in chickpea (Cicer arietinum L.) seeds, RFO accumulation and corresponding biosynthetic enzymes activities were determined during seed development of chickpea genotypes with contrasting RFO concentrations. RFO concentration in mature seeds was found as a facilitator rather than a regulating step of seed germination. In mature seeds, raffinose concentrations ranged from 0.38 to 0.68 and 0.75 to 0.99 g/100 g, whereas stachyose concentrations varied from 0.79 to 1.26 and 1.70 to 1.87 g/100 g indicating significant differences between low and high RFO genotypes, respectively. Chickpea genotypes with high RFO concentration accumulated higher concentrations of myo-inositol and sucrose during early seed developmental stages suggesting that initial substrate concentrations may influence RFO concentration in mature seeds. High RFO genotypes showed about two to three-fold higher activity for all RFO biosynthetic enzymes compared to those with low RFO concentrations. RFO biosynthetic enzymes activities correspond with accumulation of individual RFO during seed development. PMID:26953100

  17. Genotypic Variation in the Concentration of β-N-Oxalyl-L-α,β-diaminopropionic Acid (β-ODAP) in Grass Pea (Lathyrus sativus L.) Seeds Is Associated with an Accumulation of Leaf and Pod β-ODAP during Vegetative and Reproductive Stages at Three Levels of Water Stress.

    PubMed

    Xiong, Jun-Lan; Xiong, You-Cai; Bai, Xue; Kong, Hai-Yan; Tan, Rui-Yue; Zhu, Hao; Siddique, Kadambot H M; Wang, Jian-Yong; Turner, Neil C

    2015-07-15

    Grass pea (Lathyrus sativus L.) cultivation is limited because of the presence in seeds and tissues of the nonprotein amino acid β-N-oxalyl-L-α,β-diaminopropionic acid (β-ODAP), a neurotoxin that can cause lathyrism in humans. Seven grass pea genotypes differing in seed β-ODAP concentration were grown in pots at three levels of water availability to follow changes in the concentration and amount of β-ODAP in leaves and pods and seeds. The concentration and amount of β-ODAP decreased in leaves in early reproductive development and in pods as they matured, while water stress increased β-ODAP concentration in leaves and pods at these stages. The net amount of β-ODAP in leaves and pods at early podding was positively associated with seed β-ODAP concentration at maturity. We conclude that variation among genotypes in seed β-ODAP concentration results from variation in net accumulation of β-ODAP in leaves and pods during vegetative and early reproductive development.

  18. Tolerance and accumulation of hexavalent chromium by two seaweed associated aspergilli.

    PubMed

    Vala, Anjana K; Anand, Nisha; Bhatt, Purva N; Joshi, H V

    2004-05-01

    Marine seaweed (Eucheuma sp.) associated strains of Aspergillus flavus and Aspergillus niger were tested for their Cr(VI) tolerance. Both the isolates showed luxuriant growth in different concentrations of Cr(VI), i.e., 25, 50 and 100 ppm. There was no marked variation in the dry weight of control and test isolates, which indicated that both the isolates can tolerate a wide range of hexavalent chromium and their application for bioremediation purpose can be envisaged as XRF data revealed both the isolates accumulated more than 25% of the chromium supplied. A. flavus invariably exhibited higher accumulation potential. PMID:15111047

  19. Evaluating Insects as Bioindicators of Heavy Metal Contamination and Accumulation near Industrial Area of Gujrat, Pakistan

    PubMed Central

    Azam, Iqra; Afsheen, Sumera; Zia, Ahmed; Javed, Muqaddas; Saeed, Rashid; Sarwar, Muhammad Kaleem; Munir, Bushra

    2015-01-01

    To study the accumulation and contamination of heavy metals (i.e., Cd, Cr, Cu, Ni, and Zn) in soil, air, and water, few insect species were assayed as ecological indicators. Study area comes under industrial zone of district Gujrat of Punjab, Pakistan. Insects used as bioindicators included a libellulid dragonfly (Crocothemis servilia), an acridid grasshopper (Oxya hyla hyla), and a nymphalid butterfly (Danaus chrysippus) near industrial zone of Gujrat. Accumulation of Cd was highest in insect species followed by Cu, Cr, Zn, and Ni at p < 0.05. Hierarchical cluster analysis (HACA) was carried out to study metal accumulation level in all insects. Correlation and regression analysis confirmed HACA observations and declared concentration of heavy metals above permissible limits. Metal concentrations in insects were significantly higher near industries and nallahs in Gujrat and relatively higher concentrations of metals were found in Orthoptera than Odonata and Lepidoptera. The total metal concentrations in insects were pointed significantly higher at sites S3 (Mid of HalsiNala), S9 (End of HalsiNala), and S1 (Start of HalsiNala), whereas lowest value was detected at site S6 (Kalra Khasa) located far from industrial area. HACA indicates that these insect groups are potential indicators of metal contamination and can be used in biomonitoring. PMID:26167507

  20. Evaluating Insects as Bioindicators of Heavy Metal Contamination and Accumulation near Industrial Area of Gujrat, Pakistan.

    PubMed

    Azam, Iqra; Afsheen, Sumera; Zia, Ahmed; Javed, Muqaddas; Saeed, Rashid; Sarwar, Muhammad Kaleem; Munir, Bushra

    2015-01-01

    To study the accumulation and contamination of heavy metals (i.e., Cd, Cr, Cu, Ni, and Zn) in soil, air, and water, few insect species were assayed as ecological indicators. Study area comes under industrial zone of district Gujrat of Punjab, Pakistan. Insects used as bioindicators included a libellulid dragonfly (Crocothemis servilia), an acridid grasshopper (Oxya hyla hyla), and a nymphalid butterfly (Danaus chrysippus) near industrial zone of Gujrat. Accumulation of Cd was highest in insect species followed by Cu, Cr, Zn, and Ni at p < 0.05. Hierarchical cluster analysis (HACA) was carried out to study metal accumulation level in all insects. Correlation and regression analysis confirmed HACA observations and declared concentration of heavy metals above permissible limits. Metal concentrations in insects were significantly higher near industries and nallahs in Gujrat and relatively higher concentrations of metals were found in Orthoptera than Odonata and Lepidoptera. The total metal concentrations in insects were pointed significantly higher at sites S3 (Mid of HalsiNala), S9 (End of HalsiNala), and S1 (Start of HalsiNala), whereas lowest value was detected at site S6 (Kalra Khasa) located far from industrial area. HACA indicates that these insect groups are potential indicators of metal contamination and can be used in biomonitoring. PMID:26167507

  1. Evaluating Insects as Bioindicators of Heavy Metal Contamination and Accumulation near Industrial Area of Gujrat, Pakistan.

    PubMed

    Azam, Iqra; Afsheen, Sumera; Zia, Ahmed; Javed, Muqaddas; Saeed, Rashid; Sarwar, Muhammad Kaleem; Munir, Bushra

    2015-01-01

    To study the accumulation and contamination of heavy metals (i.e., Cd, Cr, Cu, Ni, and Zn) in soil, air, and water, few insect species were assayed as ecological indicators. Study area comes under industrial zone of district Gujrat of Punjab, Pakistan. Insects used as bioindicators included a libellulid dragonfly (Crocothemis servilia), an acridid grasshopper (Oxya hyla hyla), and a nymphalid butterfly (Danaus chrysippus) near industrial zone of Gujrat. Accumulation of Cd was highest in insect species followed by Cu, Cr, Zn, and Ni at p < 0.05. Hierarchical cluster analysis (HACA) was carried out to study metal accumulation level in all insects. Correlation and regression analysis confirmed HACA observations and declared concentration of heavy metals above permissible limits. Metal concentrations in insects were significantly higher near industries and nallahs in Gujrat and relatively higher concentrations of metals were found in Orthoptera than Odonata and Lepidoptera. The total metal concentrations in insects were pointed significantly higher at sites S3 (Mid of HalsiNala), S9 (End of HalsiNala), and S1 (Start of HalsiNala), whereas lowest value was detected at site S6 (Kalra Khasa) located far from industrial area. HACA indicates that these insect groups are potential indicators of metal contamination and can be used in biomonitoring.

  2. [Effects of soil type and crop genotype on cadmium accumulation in peanut (Arachis hypogaea) kernels].

    PubMed

    Wang, Shan-Shan; Zhang, Hong; Wang, Yan-Hong; Wang, Shi-Cheng; Cui, Jie-Hua; Li, Bo; Yang, Jing-Jing

    2012-08-01

    Taking burozem and fluvo-aquic soil in the main peanut (Arachis hypogaea) production areas of China as test soil types and selecting three widely cultivated peanut genotypes Baisha 1016, Huayu 22, and Zhanyou 27 as test crops, a pot experiment with no Cd addition (control) and added with 1.5 mg x kg(-1) of Cd was conducted to elucidate the effects of soil type and crop genotype on the cadmimum (Cd) accumulation in peanut kernels. In the control, the Cd concentrations in the kernels of the three peanut genotypes growing on the two soil types were lower than the national food safety standard. In treatment Cd addition, the opposite was observed. For the same soil types, the Cd concentrations in the kernels of the three peanut genotypes were significantly higher in treatment Cd addition than in the control. The Cd accumulation in the kernels of the three peanut genotypes was in the order of Zhanyou 27 > Baisha 1016 > Huayu 22, and the Cd concentrations in the kernels of the peanut genotypes growing on the two soil types were higher on burozem than on fluvo-aquic soil. The values of the Cd bioaccumulation factor for the kernels of the three peanut genotypes were all higher than 1.0 in the control but lower than 1.0 in treatment Cd addition, suggesting that the peanut kernels had a stronger ability in accumulating the Cd from soil, and, when the soil Cd concentration increased, this ability decreased.

  3. [Cadmium-hyperaccumulator Solanum nigrum L. and its accumulating characteristics].

    PubMed

    Wei, Shu-he; Zhou, Qi-xing; Wang, Xin

    2005-05-01

    It is main groundwork and the first step of phytoextraction of its commercial application on a large scale to screen out a series of ideal hyperaccumulators that can effectively remedy contaminated soil by heavy metals, which is also difficult point and front field of contaminated environment phytoremediation. With the properties of strong endurance to adverse environment, fast growing and high reproduction, especially the characteristic of the biomass could increase sharply under feasible environmental factors, weed can supply a gap of discovered hyperaccumulating plants, so it is a kind of ideal remediative resource. A cadmium-hyperaccumulator Solanum nigrum L. (weed) was first discovered by using the pot-culture method arranged in outdoor and sampling-analyzing experiments carried out in heavy metal contaminated areas. The pot-culture experiments show that the average concentration of Cd in stems and leaves of S. nigrum growing in soil added with 25 mg/kg of Cd were all greater than the accepted critical concentration of 100 mg/kg what Cd hyperaccumulator should accumulate. The Cd concentration in its overground parts was higher than that in its roots, and the Cd accumulation coefficient in its overground parts was higher than 1 too. Compared with the control, the overground biomass of S. nigrum under the condition of 25 mg/kg (Cd) was not decreased significantly. Furthermore, it was also confirmed that S. nigrum had basic characteristics of Cd-hyperaccumulator by sample-analyze experiment in contaminated area with heavy metals. This kind of method of identifying hyper accumulators in a clean area is useful to the discovery of materials applied to the phytoremediation of contaminated soils with Cd. PMID:16124492

  4. Transport and intracellular accumulation of acetaldehyde in Saccharomyces cerevisiae

    SciTech Connect

    Stanley, G.A.; Pamment, N.B. )

    1993-06-05

    The rate of acetaldehyde efflux from yeast cells and its intracellular concentration were studied in the light of recent suggestions that acetaldehyde inhibition may be an important factor in yeast ethanol fermentations. When the medium surrounding cells containing ethanol and acetaldehyde was suddenly diluted, the rate of efflux of acetaldehyde was slow relative to the rate of ethanol efflux, suggesting that acetaldehyde, unlike ethanol, may accumulate intracellularly. Intracellular acetaldehyde concentrations were measured during high cell density fermentations, using direct injection gas chromatography to avoid the need to concentrate or disrupt the cells. Intracellular acetaldehyde concentrations substantially exceeded the extracellular concentrations throughout fermentation and were generally much higher than the acetaldehyde concentrations normally recorded in the culture broth in ethanol fermentations. The technique used was sensitive to the time taken to cool and freeze the samples. Measured intracellular acetaldehyde concentrations fell rapidly as the time taken to freeze the suspensions was extended beyond 2 s. The results add weight to recent claims that acetaldehyde toxicity is responsible for some of the effects previously ascribed to ethanol in alcohol fermentations, especially Zymomonas fermentations. Further work is required to confirm the importance of acetaldehyde toxicity under other culture conditions.

  5. The impact of aeration on the competition between polyphosphate accumulating organisms and glycogen accumulating organisms.

    PubMed

    Carvalheira, Mónica; Oehmen, Adrian; Carvalho, Gilda; Eusébio, Mário; Reis, Maria A M

    2014-12-01

    In wastewater treatment plants (WWTPs), aeration is the major energetic cost, thus its minimisation will improve the cost-effectiveness of the process. This study shows that both the dissolved oxygen (DO) concentration and aerobic hydraulic retention time (HRT) affect the competition between polyphosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs). At low DO levels, Accumulibacter PAOs were shown to have an advantage over Competibacter GAOs, as PAOs had a higher oxygen affinity and thus largely maintained their aerobic activity at low DO levels, while GAO activity decreased. Bioreactor operation at low DO levels was found to increase the PAO fraction of the sludge. Furthermore, an increase in aerobic HRT (at a DO level of 2 mg O2/L), promoted the proliferation of GAOs over PAOs, decreasing the EBPR efficiency. Overall, this study shows that low aeration can be beneficial for EBPR performance through selecting for PAOs over GAOs, which should be incorporated into WWTP models in order to minimise energetic costs and improve WWTP sustainability. PMID:25222333

  6. Water management affects arsenic and cadmium accumulation in different rice cultivars.

    PubMed

    Hu, Pengjie; Huang, Jiexue; Ouyang, Younan; Wu, Longhua; Song, Jing; Wang, Songfeng; Li, Zhu; Han, Cunliang; Zhou, Liqiang; Huang, Yujuan; Luo, Yongming; Christie, Peter

    2013-12-01

    Paddy rice (Oryza sativa L.) is a staple food and one of the major sources of dietary arsenic (As) and cadmium (Cd) in Asia. A field experiment was conducted to investigate the effects of four water management regimes (aerobic, intermittent irrigation, conventional irrigation and flooding) on As and Cd accumulation in seven major rice cultivars grown in Zhejiang province, east China. With increasing irrigation from aerobic to flooded conditions, the soil HCl-extractable As concentrations increased significantly and the HCl-extractable Cd concentrations decreased significantly. These trends were consistent with the As and Cd concentrations in the straw, husk and brown rice. Water management both before and after the full tillering stage affected As and Cd accumulation in the grains. The intermittent and conventional treatments produced higher grain yields than the aerobic and flooded treatments. Cd concentrations in brown rice varied 13.1-40.8 times and As varied 1.75-8.80 times among the four water management regimes. Cd and As accumulation in brown rice varied among the rice cultivars, with Guodao 6 (GD6) was a low Cd but high-As-accumulating cultivar while Indonesia (IR) and Yongyou 9 (YY9) were low As but high-Cd-accumulating cultivars. Brown rice Cd and As concentrations in the 7 cultivars were significantly negatively correlated. The results indicate that As and Cd accumulated in rice grains with opposite trends that were influenced by both water management and rice cultivar. Production of 'safe' rice with respect to As and Cd might be possible by balancing water management and rice cultivar according to the severity of soil pollution. PMID:23719663

  7. Factors influencing cadmium accumulation and its toxicity to marine organisms

    PubMed Central

    Engel, David W.; Fowler, Bruce A.

    1979-01-01

    The toxicity of dissolved cadmium to a variety of marine animals has been found to be related to salinity, with decreased toxicity observed at higher salinities. Recent data from our laboratory have demonstrated that the toxicity of cadmium to estuarine shrimp and larval fish is a function of free cadmium ion concentration, which in turn is controlled by the chloride concentration of the water. As the chloride concentration (i.e., salinity of the water) increases, the concentration of free cadmium ion decreases relative to total dissolved metal, due to its complexation with chloride ions. These observations have been given further support by measurements involving the uptake of 115mCd by shrimp which showed that accumulation of 115mCd and chloride concentration also are inversely related. Experiments also have been conducted on the physiological effects of cadmium on the respiration of excised oyster gill tissue. Although tissues from oysters exposed for 14 days to 0.1 ppm total dissolved cadmium accumulated significant quantities of metal, no measurable effects on respiration rates were detected. Higher doses (0.3 and 0.6 ppm) caused both mortalities of oysters and accelerated respiration of excised oyster gill. Exposure to 0.1 ppm cadmium also caused the induction of and/or increased binding of cadmium to a specific low molecular weight protein in oysters. This protein appeared to have a detoxification function at low cadmium exposure levels, but in animals exposed to 0.6 ppm cadmium the induction mechanism apparently became saturated, allowing the excess cadmium to bind critical sites with resultant damage. PMID:488052

  8. Neurodegeneration with Brain Iron Accumulation

    MedlinePlus

    ... Diversity Find People About NINDS NINDS Neurodegeneration with Brain Iron Accumulation Information Page Synonym(s): Hallervorden-Spatz Disease, ... done? Clinical Trials Organizations What is Neurodegeneration with Brain Iron Accumulation? Neurodegeneration with brain iron accumulation (NBIA) ...

  9. Mercury accumulation in sediments and seabird feathers from the Antarctic Peninsula.

    PubMed

    Calle, Paola; Alvarado, Omar; Monserrate, Lorena; Cevallos, Juan Manuel; Calle, Nastenka; Alava, Juan José

    2015-02-28

    In an effort to assess the impact of mercury in the Antarctic Peninsula, we conducted ecotoxicological research in this region during the summer of 2012 and 2013. The objectives were to assess: (a) mercury levels in sediment samples; (b) mercury accumulation in Antarctic seabird feathers: Catharacta lonnbergi (brown skua), Pygoscelis papua (gentoo penguin) and Pygoscelis antarctica (chinstrap penguin); and (c) biomagnification (BMF predator/prey) and biota sediment accumulation (BSAF skuas/sediment) factors. Mercury concentrations in sediment were relatively low. Mercury concentrations were significantly higher in brown skuas and gentoo penguins than in chinstrap penguins (2012), and significantly higher in brown skuas than in both penguins (2013). BMF indicated 2-7.5 times greater mercury levels in brown skuas than in penguins. BSAF values suggested an apparent temporal decrease of 18.2% of this ratio from 2012 to 2013. Long-range environmental transport is the likely route of entry of mercury into the Antarctic Peninsula.

  10. Plastids and Carotenoid Accumulation.

    PubMed

    Li, Li; Yuan, Hui; Zeng, Yunliu; Xu, Qiang

    2016-01-01

    Plastids are ubiquitously present in plants and are the organelles for carotenoid biosynthesis and storage. Based on their morphology and function, plastids are classified into various types, i.e. proplastids, etioplasts, chloroplasts, amyloplasts, and chromoplasts. All plastids, except proplastids, can synthesize carotenoids. However, plastid types have a profound effect on carotenoid accumulation and stability. In this chapter, we discuss carotenoid biosynthesis and regulation in various plastids with a focus on carotenoids in chromoplasts. Plastid transition related to carotenoid biosynthesis and the different capacity of various plastids to sequester carotenoids and the associated effect on carotenoid stability are described in light of carotenoid accumulation in plants. PMID:27485226

  11. Plastids and Carotenoid Accumulation.

    PubMed

    Li, Li; Yuan, Hui; Zeng, Yunliu; Xu, Qiang

    2016-01-01

    Plastids are ubiquitously present in plants and are the organelles for carotenoid biosynthesis and storage. Based on their morphology and function, plastids are classified into various types, i.e. proplastids, etioplasts, chloroplasts, amyloplasts, and chromoplasts. All plastids, except proplastids, can synthesize carotenoids. However, plastid types have a profound effect on carotenoid accumulation and stability. In this chapter, we discuss carotenoid biosynthesis and regulation in various plastids with a focus on carotenoids in chromoplasts. Plastid transition related to carotenoid biosynthesis and the different capacity of various plastids to sequester carotenoids and the associated effect on carotenoid stability are described in light of carotenoid accumulation in plants.

  12. Cadmium accumulation in the rootless macrophyte Wolffia globosa and its potential for phytoremediation.

    PubMed

    Xie, Wan-Ying; Huang, Qing; Li, Gang; Rensing, Christopher; Zhu, Yong-Guan

    2013-01-01

    Cadmium (Cd) pollution around the world is a serious issue demanding acceptable solutions, one of which is phytoremediation that is both cost-effective and eco-friendly. Removal of Cd from contaminated water using plants with high growth rates and sufficient Cd accumulation abilities could be an appropriate choice. Here, we investigated a potential Cd accumulator, Wolffia, a rootless duckweed with high growth rate. Cd uptake, accumulation, tolerance, and phytofiltration ability by Wolffia globosa were examined. Furthermore, the effects of arsenic (As) on Cd uptake and phytofiltration by W. globosa were also studied. Cd uptake kinetics showed a linear pattern and a hyperbolic pattern without a plateau in lower (0-2 microM) and higher (0-200 microM) Cd concentration ranges, respectively, suggesting rapid Cd uptake by W. globosa Cd accumulation ability by W. globosa was higher at Cd concentrations < 10 microM than at >10 microM. All the five species of Wolffia exposed to I microM Cd for 5 days accumulated > 500 mg Cd kg(-1) DW. Ten gram fresh W. globosa could diminish almost all the Cd (2 microM) in a 200 mL solution. This enormous accumulation ability was mostly due to passive adsorption of Cd by the apoplast. Arsenic had no significant effect on Cd uptake and phytofiltration. The fresh fronds also showed a great As extracting ability. The results indicated that Wolffia is a strong Cd accumulator and has great Cd phytoremediation potential. Therefore, this plant can be used in fresh aquatic environments co-contaminated by low-levels of Cd and As. PMID:23488004

  13. Aluminum inhibits root growth and induces hydrogen peroxide accumulation in Plantago algarbiensis and P. almogravensis seedlings.

    PubMed

    Martins, Neusa; Gonçalves, Sandra; Romano, Anabela

    2013-12-01

    We have evaluated the impact of aluminum (Al) on germination, relative root growth, Al accumulation in roots tips, H2O2 levels, plasma membrane integrity, pigment levels, protein content, and the activities of superoxide dismutase (SOD) and catalase (CAT) in seedlings of the endangered Portuguese species Plantago algarbiensis and Plantago almogravensis. We found that up to 400 μM Al had no impact on the germination percentage in either species but inhibited root growth in a concentration-dependent manner (more severely in P. algarbiensis). Al accumulation in the root tips of both species was concentration dependent up to 200 μM but declined thereafter despite the absence of membrane damage. We observed a concentration-dependent induction of SOD activity but no change in CAT activity resulting in the accumulation of H2O2 (a known growth inhibitor), although its impact in P. almogravensis may be partially ameliorated by the accumulation of carotenoid pigments. Our data suggest an association between Al uptake, H2O2 production, and the inhibition of root growth during early seedling development in P. algarbiensis and P. almogravensis, although the latter is more tolerant towards higher concentrations of the metal. PMID:23702818

  14. Purification and partial kinetic and physical characterization of two NADP-specific glutamate dehydrogenase isoenzymes and their protein precursors, and measurement of the patterns of accumulation and rates of degradation of their nonidentical subunits in synchronized cells of Chlorella cultured in different concentrations of ammonia

    SciTech Connect

    Bascomb, N.F.

    1986-01-01

    Two ammonium-inducible, chloroplast-localized, NADP-specific glutamate dehydrogenases were purified from Chlorella sorokiniana. They were homopolymers of either alpha or beta subunits with molecular weights of 55,500 and 53,000, respectively. These isoenzymes were separated by their differential binding to the substrate affinity column. Peptide mapping of purified alpha and beta subunits showed them to have a high degree of sequence homology. By use of SDS slab-gel electrophoresis and a Western blot/immunodetection procedure, patterns of accumulation of alpha and beta subunits (in their holoenzyme) were measured in cells cultured in media, containing different concentrations of ammonia. Pulse-chase experiments with (/sup 35/S)sulfate were performed to measured the rates of degradation of the two isoenzymes. When the culture medium contained 2 mM ammonia or lower, cells accumulated only the alpha holoenzyme. Above 2 mM ammonia, cells contained both enzymes; however, their patterns of accumulation and rates of degradation were very different. The physiological role of alpha and beta holoenzymes appears to be ammonia assimilation at low and high external ammonia concentrations, respectively. From in vitro-translation studies with total cellular poly(A)/sup +/RNA, isolated from cells engaged in synthesis of alpha or beta holoenzymes or both, it was concluded that alpha and beta subunits have protein precursor(s) or identical molecular weight (M/sub r/ = 58,500). When the putative protein-precursor(s) were incubated in vitro, with cell-free extracts from Chlorella cells, they were processed to proteins the size of alpha and beta subunits.

  15. Accumulation of perchlorate in aquatic and terrestrial plants at a field scale.

    PubMed

    Tan, Kui; Anderson, Todd A; Jones, Matthew W; Smith, Philip N; Jackson, W Andrew

    2004-01-01

    Previous laboratory-scale studies have documented perchlorate ClO(-)(4) uptake by different plant species, but less information is available at field scale, where ClO(-)(4) uptake may be affected by environmental conditions, such as distance to streams or shallow water tables, exposure duration, and species. This study examined uptake of ClO(-)(4) in smartweed (Polygonum spp.) and watercress (Nasturtium spp.) as well as more than forty trees, including ash (Fraxinus greggii A. Gray), chinaberry (Melia azedarach L.), elm (Ulmus parvifolia Jacq.), willow (Salix nigra Marshall), mulberry [Broussonetia papyrifera (L.) Vent.], and hackberry (Celtis laevigata Willd.) from multiple streams surrounding a perchlorate-contaminated site. Results indicate a large potential for ClO(-)(4) accumulation in aquatic and terrestrial plants, with ClO(-)(4) concentration in plant tissues approximately 100 times higher than that in bulk water. Perchlorate accumulation in leaves of terrestrial plants was also dependent on species, with hackberry, willow, and elm having a strong potential to accumulate ClO(-)(4). Generally, trees located closer to the stream had a higher ClO(-)(4) accumulation than trees located farther away from the stream. Seasonal leaf sampling of terrestrial plants indicated that ClO(-)(4) accumulation also was affected by exposure duration, with highest accumulation observed in the late growing cycle, although leaf concentrations for a given tree were highly variable. Perchlorate may be re-released into the environment via leaching and rainfall as indicated by lower perchlorate concentrations in collected leaf litter. Information obtained from this study will be helpful to understand the fate of ClO(-)(4) in macrophytes and natural systems.

  16. Accumulation of perchlorate in aquatic and terrestrial plants at a field scale.

    PubMed

    Tan, Kui; Anderson, Todd A; Jones, Matthew W; Smith, Philip N; Jackson, W Andrew

    2004-01-01

    Previous laboratory-scale studies have documented perchlorate ClO(-)(4) uptake by different plant species, but less information is available at field scale, where ClO(-)(4) uptake may be affected by environmental conditions, such as distance to streams or shallow water tables, exposure duration, and species. This study examined uptake of ClO(-)(4) in smartweed (Polygonum spp.) and watercress (Nasturtium spp.) as well as more than forty trees, including ash (Fraxinus greggii A. Gray), chinaberry (Melia azedarach L.), elm (Ulmus parvifolia Jacq.), willow (Salix nigra Marshall), mulberry [Broussonetia papyrifera (L.) Vent.], and hackberry (Celtis laevigata Willd.) from multiple streams surrounding a perchlorate-contaminated site. Results indicate a large potential for ClO(-)(4) accumulation in aquatic and terrestrial plants, with ClO(-)(4) concentration in plant tissues approximately 100 times higher than that in bulk water. Perchlorate accumulation in leaves of terrestrial plants was also dependent on species, with hackberry, willow, and elm having a strong potential to accumulate ClO(-)(4). Generally, trees located closer to the stream had a higher ClO(-)(4) accumulation than trees located farther away from the stream. Seasonal leaf sampling of terrestrial plants indicated that ClO(-)(4) accumulation also was affected by exposure duration, with highest accumulation observed in the late growing cycle, although leaf concentrations for a given tree were highly variable. Perchlorate may be re-released into the environment via leaching and rainfall as indicated by lower perchlorate concentrations in collected leaf litter. Information obtained from this study will be helpful to understand the fate of ClO(-)(4) in macrophytes and natural systems. PMID:15356223

  17. Effect of temperature on accumulation of methylmercuric chloride and p,p'DDT by rainbow trout (Salmo gairdneri)

    USGS Publications Warehouse

    Reinert, Robert E.; Stone, Linda J.; Willford, Wayne A.

    1974-01-01

    Amounts of mercury and DDT residues accumulated from water by yearling rainbow trout (Salmo gairdneri) in the laboratory increased as water temperature increased. Fish exposed to methylmercuric chloride at concentrations of 234–263 parts per trillion for 12 wk at 5, 10, and 15 C accumulated 1.19, 1.71, and 1.96 ppm; fish exposed to p,p′DDT at concentrations of 133–176 parts per trillion accumulated 3.76, 5.93, and 6.82 ppm. Concentrations of mercury accumulated by the fish were significantly different (P < 0.01) at each of the three temperatures, and the concentrations of DDT were significantly different at 5 and 10 and 5 and 15 C. Throughout the period of exposure, the concentration factors (concentration of contaminant in the fish/concentration in water) at each of the three temperatures were far higher for p,p′DDT than for methylmercuric chloride.

  18. Accumulation of methylmercury in the earthworm, Eisenia foetida, and its effect on regeneration

    SciTech Connect

    Beyer, W.N.; Cromartie, E.; Moment, G.B.

    1985-08-01

    Earthworms provide an appropriate model for evaluating the environmental hazards of metals in soil, and they are also excellent organisms for studying the process of regeneration. Two studies have found that concentrations of mercury in earthworms were higher than those in the soil where they lived. This study investigates the accumulation of methylmercury in the earthworm, Eisenia foetida (Savigny), and its effect on regeneration after excision of the caudal end.

  19. Effects of perchlorate on growth of four wetland plants and its accumulation in plant tissues.

    PubMed

    He, Hongzhi; Gao, Haishuo; Chen, Guikui; Li, Huashou; Lin, Hai; Shu, Zhenzhen

    2013-10-01

    Perchlorate contamination in water is of concern because of uncertainties about toxicity and health effects, impact on ecosystems, and possible indirect exposure pathways to humans. Therefore, it is very important to investigate the ecotoxicology of perchlorate and to screen plant species for phytoremediation. Effects of perchlorate (20, 200, and 500 mg/L) on the growth of four wetland plants (Eichhornia crassipes, Acorus calamus L., Thalia dealbata, and Canna indica) as well as its accumulation in different plant tissues were investigated through water culture experiments. Twenty milligrams per liter of perchlorate had no significant effects on height, root length, aboveground part weight, root weight, and oxidizing power of roots of four plants, except A. calamus, and increasing concentrations of perchlorate showed that out of the four wetland plants, only A. calamus had a significant (p<0.05) dose-dependent decrease in these parameters. When treated with 500 mg/L perchlorate, these parameters and chlorophyll content in the leaf of plants showed significant decline contrasted to control groups, except the root length of E. crassipes and C. indica. The order of inhibition rates of perchlorate on root length, aboveground part weight and root weight, and oxidizing power of roots was: A. calamus > C. indica > T. dealbata > E. crassipes and on chlorophyll content in the leaf it was: A. calamus > T. dealbata > C. indica > E. crassipes. The higher the concentration of perchlorate used, the higher the amount of perchlorate accumulation in plants. Perchlorate accumulation in aboveground tissues was much higher than that in underground tissues and leaf was the main tissue for perchlorate accumulation. The order of perchlorate accumulation content and the bioconcentration factor in leaf of four plants was: E. crassipes > C. indica > T. dealbata > A. calamus. Therefore, E. crassipes might be an ideal plant with high tolerance ability and accumulation ability for constructing

  20. Effects of perchlorate on growth of four wetland plants and its accumulation in plant tissues.

    PubMed

    He, Hongzhi; Gao, Haishuo; Chen, Guikui; Li, Huashou; Lin, Hai; Shu, Zhenzhen

    2013-10-01

    Perchlorate contamination in water is of concern because of uncertainties about toxicity and health effects, impact on ecosystems, and possible indirect exposure pathways to humans. Therefore, it is very important to investigate the ecotoxicology of perchlorate and to screen plant species for phytoremediation. Effects of perchlorate (20, 200, and 500 mg/L) on the growth of four wetland plants (Eichhornia crassipes, Acorus calamus L., Thalia dealbata, and Canna indica) as well as its accumulation in different plant tissues were investigated through water culture experiments. Twenty milligrams per liter of perchlorate had no significant effects on height, root length, aboveground part weight, root weight, and oxidizing power of roots of four plants, except A. calamus, and increasing concentrations of perchlorate showed that out of the four wetland plants, only A. calamus had a significant (p<0.05) dose-dependent decrease in these parameters. When treated with 500 mg/L perchlorate, these parameters and chlorophyll content in the leaf of plants showed significant decline contrasted to control groups, except the root length of E. crassipes and C. indica. The order of inhibition rates of perchlorate on root length, aboveground part weight and root weight, and oxidizing power of roots was: A. calamus > C. indica > T. dealbata > E. crassipes and on chlorophyll content in the leaf it was: A. calamus > T. dealbata > C. indica > E. crassipes. The higher the concentration of perchlorate used, the higher the amount of perchlorate accumulation in plants. Perchlorate accumulation in aboveground tissues was much higher than that in underground tissues and leaf was the main tissue for perchlorate accumulation. The order of perchlorate accumulation content and the bioconcentration factor in leaf of four plants was: E. crassipes > C. indica > T. dealbata > A. calamus. Therefore, E. crassipes might be an ideal plant with high tolerance ability and accumulation ability for constructing

  1. Chimpanzee accumulative stone throwing.

    PubMed

    Kühl, Hjalmar S; Kalan, Ammie K; Arandjelovic, Mimi; Aubert, Floris; D'Auvergne, Lucy; Goedmakers, Annemarie; Jones, Sorrel; Kehoe, Laura; Regnaut, Sebastien; Tickle, Alexander; Ton, Els; van Schijndel, Joost; Abwe, Ekwoge E; Angedakin, Samuel; Agbor, Anthony; Ayimisin, Emmanuel Ayuk; Bailey, Emma; Bessone, Mattia; Bonnet, Matthieu; Brazolla, Gregory; Buh, Valentine Ebua; Chancellor, Rebecca; Cipoletta, Chloe; Cohen, Heather; Corogenes, Katherine; Coupland, Charlotte; Curran, Bryan; Deschner, Tobias; Dierks, Karsten; Dieguez, Paula; Dilambaka, Emmanuel; Diotoh, Orume; Dowd, Dervla; Dunn, Andrew; Eshuis, Henk; Fernandez, Rumen; Ginath, Yisa; Hart, John; Hedwig, Daniela; Ter Heegde, Martijn; Hicks, Thurston Cleveland; Imong, Inaoyom; Jeffery, Kathryn J; Junker, Jessica; Kadam, Parag; Kambi, Mohamed; Kienast, Ivonne; Kujirakwinja, Deo; Langergraber, Kevin; Lapeyre, Vincent; Lapuente, Juan; Lee, Kevin; Leinert, Vera; Meier, Amelia; Maretti, Giovanna; Marrocoli, Sergio; Mbi, Tanyi Julius; Mihindou, Vianet; Moebius, Yasmin; Morgan, David; Morgan, Bethan; Mulindahabi, Felix; Murai, Mizuki; Niyigabae, Protais; Normand, Emma; Ntare, Nicolas; Ormsby, Lucy Jayne; Piel, Alex; Pruetz, Jill; Rundus, Aaron; Sanz, Crickette; Sommer, Volker; Stewart, Fiona; Tagg, Nikki; Vanleeuwe, Hilde; Vergnes, Virginie; Willie, Jacob; Wittig, Roman M; Zuberbuehler, Klaus; Boesch, Christophe

    2016-01-01

    The study of the archaeological remains of fossil hominins must rely on reconstructions to elucidate the behaviour that may have resulted in particular stone tools and their accumulation. Comparatively, stone tool use among living primates has illuminated behaviours that are also amenable to archaeological examination, permitting direct observations of the behaviour leading to artefacts and their assemblages to be incorporated. Here, we describe newly discovered stone tool-use behaviour and stone accumulation sites in wild chimpanzees reminiscent of human cairns. In addition to data from 17 mid- to long-term chimpanzee research sites, we sampled a further 34 Pan troglodytes communities. We found four populations in West Africa where chimpanzees habitually bang and throw rocks against trees, or toss them into tree cavities, resulting in conspicuous stone accumulations at these sites. This represents the first record of repeated observations of individual chimpanzees exhibiting stone tool use for a purpose other than extractive foraging at what appear to be targeted trees. The ritualized behavioural display and collection of artefacts at particular locations observed in chimpanzee accumulative stone throwing may have implications for the inferences that can be drawn from archaeological stone assemblages and the origins of ritual sites.

  2. Chimpanzee accumulative stone throwing

    PubMed Central

    Kühl, Hjalmar S.; Kalan, Ammie K.; Arandjelovic, Mimi; Aubert, Floris; D’Auvergne, Lucy; Goedmakers, Annemarie; Jones, Sorrel; Kehoe, Laura; Regnaut, Sebastien; Tickle, Alexander; Ton, Els; van Schijndel, Joost; Abwe, Ekwoge E.; Angedakin, Samuel; Agbor, Anthony; Ayimisin, Emmanuel Ayuk; Bailey, Emma; Bessone, Mattia; Bonnet, Matthieu; Brazolla, Gregory; Buh, Valentine Ebua; Chancellor, Rebecca; Cipoletta, Chloe; Cohen, Heather; Corogenes, Katherine; Coupland, Charlotte; Curran, Bryan; Deschner, Tobias; Dierks, Karsten; Dieguez, Paula; Dilambaka, Emmanuel; Diotoh, Orume; Dowd, Dervla; Dunn, Andrew; Eshuis, Henk; Fernandez, Rumen; Ginath, Yisa; Hart, John; Hedwig, Daniela; Ter Heegde, Martijn; Hicks, Thurston Cleveland; Imong, Inaoyom; Jeffery, Kathryn J.; Junker, Jessica; Kadam, Parag; Kambi, Mohamed; Kienast, Ivonne; Kujirakwinja, Deo; Langergraber, Kevin; Lapeyre, Vincent; Lapuente, Juan; Lee, Kevin; Leinert, Vera; Meier, Amelia; Maretti, Giovanna; Marrocoli, Sergio; Mbi, Tanyi Julius; Mihindou, Vianet; Moebius, Yasmin; Morgan, David; Morgan, Bethan; Mulindahabi, Felix; Murai, Mizuki; Niyigabae, Protais; Normand, Emma; Ntare, Nicolas; Ormsby, Lucy Jayne; Piel, Alex; Pruetz, Jill; Rundus, Aaron; Sanz, Crickette; Sommer, Volker; Stewart, Fiona; Tagg, Nikki; Vanleeuwe, Hilde; Vergnes, Virginie; Willie, Jacob; Wittig, Roman M.; Zuberbuehler, Klaus; Boesch, Christophe

    2016-01-01

    The study of the archaeological remains of fossil hominins must rely on reconstructions to elucidate the behaviour that may have resulted in particular stone tools and their accumulation. Comparatively, stone tool use among living primates has illuminated behaviours that are also amenable to archaeological examination, permitting direct observations of the behaviour leading to artefacts and their assemblages to be incorporated. Here, we describe newly discovered stone tool-use behaviour and stone accumulation sites in wild chimpanzees reminiscent of human cairns. In addition to data from 17 mid- to long-term chimpanzee research sites, we sampled a further 34 Pan troglodytes communities. We found four populations in West Africa where chimpanzees habitually bang and throw rocks against trees, or toss them into tree cavities, resulting in conspicuous stone accumulations at these sites. This represents the first record of repeated observations of individual chimpanzees exhibiting stone tool use for a purpose other than extractive foraging at what appear to be targeted trees. The ritualized behavioural display and collection of artefacts at particular locations observed in chimpanzee accumulative stone throwing may have implications for the inferences that can be drawn from archaeological stone assemblages and the origins of ritual sites. PMID:26923684

  3. Chimpanzee accumulative stone throwing.

    PubMed

    Kühl, Hjalmar S; Kalan, Ammie K; Arandjelovic, Mimi; Aubert, Floris; D'Auvergne, Lucy; Goedmakers, Annemarie; Jones, Sorrel; Kehoe, Laura; Regnaut, Sebastien; Tickle, Alexander; Ton, Els; van Schijndel, Joost; Abwe, Ekwoge E; Angedakin, Samuel; Agbor, Anthony; Ayimisin, Emmanuel Ayuk; Bailey, Emma; Bessone, Mattia; Bonnet, Matthieu; Brazolla, Gregory; Buh, Valentine Ebua; Chancellor, Rebecca; Cipoletta, Chloe; Cohen, Heather; Corogenes, Katherine; Coupland, Charlotte; Curran, Bryan; Deschner, Tobias; Dierks, Karsten; Dieguez, Paula; Dilambaka, Emmanuel; Diotoh, Orume; Dowd, Dervla; Dunn, Andrew; Eshuis, Henk; Fernandez, Rumen; Ginath, Yisa; Hart, John; Hedwig, Daniela; Ter Heegde, Martijn; Hicks, Thurston Cleveland; Imong, Inaoyom; Jeffery, Kathryn J; Junker, Jessica; Kadam, Parag; Kambi, Mohamed; Kienast, Ivonne; Kujirakwinja, Deo; Langergraber, Kevin; Lapeyre, Vincent; Lapuente, Juan; Lee, Kevin; Leinert, Vera; Meier, Amelia; Maretti, Giovanna; Marrocoli, Sergio; Mbi, Tanyi Julius; Mihindou, Vianet; Moebius, Yasmin; Morgan, David; Morgan, Bethan; Mulindahabi, Felix; Murai, Mizuki; Niyigabae, Protais; Normand, Emma; Ntare, Nicolas; Ormsby, Lucy Jayne; Piel, Alex; Pruetz, Jill; Rundus, Aaron; Sanz, Crickette; Sommer, Volker; Stewart, Fiona; Tagg, Nikki; Vanleeuwe, Hilde; Vergnes, Virginie; Willie, Jacob; Wittig, Roman M; Zuberbuehler, Klaus; Boesch, Christophe

    2016-01-01

    The study of the archaeological remains of fossil hominins must rely on reconstructions to elucidate the behaviour that may have resulted in particular stone tools and their accumulation. Comparatively, stone tool use among living primates has illuminated behaviours that are also amenable to archaeological examination, permitting direct observations of the behaviour leading to artefacts and their assemblages to be incorporated. Here, we describe newly discovered stone tool-use behaviour and stone accumulation sites in wild chimpanzees reminiscent of human cairns. In addition to data from 17 mid- to long-term chimpanzee research sites, we sampled a further 34 Pan troglodytes communities. We found four populations in West Africa where chimpanzees habitually bang and throw rocks against trees, or toss them into tree cavities, resulting in conspicuous stone accumulations at these sites. This represents the first record of repeated observations of individual chimpanzees exhibiting stone tool use for a purpose other than extractive foraging at what appear to be targeted trees. The ritualized behavioural display and collection of artefacts at particular locations observed in chimpanzee accumulative stone throwing may have implications for the inferences that can be drawn from archaeological stone assemblages and the origins of ritual sites. PMID:26923684

  4. Accumulation of ergot alkaloids during conidiophore development in Aspergillus fumigatus.

    PubMed

    Mulinti, Prashanthi; Allen, Natalie A; Coyle, Christine M; Gravelat, Fabrice N; Sheppard, Donald C; Panaccione, Daniel G

    2014-01-01

    Production of ergot alkaloids in the opportunistic fungal pathogen Aspergillus fumigatus is restricted to conidiating cultures. These cultures typically accumulate several pathway intermediates at concentrations comparable to that of the pathway end product. We investigated the contribution of different cell types that constitute the multicellular conidiophore of A. fumigatus to the production of ergot alkaloid pathway intermediates versus the pathway end product, fumigaclavine C. A relatively minor share (11 %) of the ergot alkaloid yield on a molar basis was secreted into the medium, whereas the remainder was associated with the conidiating colonies. Entire conidiating cultures (containing hyphae, vesicle of conidiophore, phialides of conidiophore, and conidia) accumulated higher levels of the pathway intermediate festuclavine and lower levels of the pathway end product fumigaclavine C than did isolated, abscised conidia, indicating that conidiophores and/or hyphae have a quantitatively different ergot alkaloid profile compared to that of conidia. Differences in alkaloid accumulation among cell types also were indicated by studies with conidiophore development mutants. A ∆medA mutant, in which conidiophores are numerous but develop poorly, accumulated higher levels of pathway intermediates than did the wildtype or a complemented ∆medA mutant. A ∆stuA mutant, which grows mainly as hyphae and produces very few, abnormal conidiophores, produced no detectable ergot alkaloids. The data indicated heterogeneous spatial distribution of ergot alkaloid pathway intermediates versus pathway end product in conidiating cultures of A. fumigatus. This skewed distribution may reflect differences in abundance or activity of pathway enzymes among cell types of those conidiating cultures. PMID:23925951

  5. Effect of end-of-day irradiations on polyamine accumulation in petal cultures of Araujia sericifera.

    PubMed

    Moysset, Luisa; Trull, Olga; Santos, M. Asunción; Simón, Esther; Torné, Josep M

    2002-01-01

    We have studied photoperiodic control and the effect of phytochrome photoconversion at the end-of-day (EOD) on polyamine (PA) accumulation in petal explants of Araujia sericifera. Petals from immature flowers were cultured under long (LD) and short (SD) days. Light was provided by Gro-lux fluorescent lamps (90-100 &mgr;mol m-2 s-1). Red (R), far red (FR), red followed by far-red (R-FR) and far-red followed by red (FR-R) light treatments were applied daily at the end of the photoperiod. The free and bound putrescine (Put), spermidine (Spd) and spermine (Spm) fractions in petal explants were determined 40 days after the beginning of the culture. We also aimed to clarify the involvement of PA changes by using two inhibitors of PA biosynthesis: D-l-alpha-difluoromethylarginine (DFMA) and methylglyoxal bis(guanylhydrazone) (MGBG). We found PA accumulation to be under photoperiodic control, and the inhibitory effect of DFMA on this accumulation suggests that arginine decarboxylase (ADC) is the major pathway for Put biosynthesis. Polyamine levels were higher under LD, mainly as a result of the accumulation of free and bound Put. FR-EOD treatment, which dramatically reduced the R : FR ratio after LD, increased the accumulation of PA, mainly as free Put and free and bound Spd. Sequential R-FR and FR-R-EOD treatments strongly increased bound Spd. The concentration of MGBG used increased total PA accumulation, mainly as Put. However, all EOD light treatments dramatically reduced Put accumulation in the presence of MGBG. This may be due to a dual role of FR light in PA accumulation: (1) FR per se stimulates PA production, probably via ADC, and (2) in the presence of MGBG, FR inhibits Put accumulation, probably via ethylene production.

  6. [Effects of farmland use type and winter irrigation on nitrate accumulation in sandy farmland soil].

    PubMed

    Yang, Rong; Su, Yong-zhong

    2009-03-01

    With the sandy farmland in the marginal oasis in middle reaches of Heihe River Basin, Northwest China as test object, this paper studied soil NO3- -N accumulation and leaching under effects of different farmland use type and winter irrigation. The results showed that the mean NO3- -N concentration in 0-300 cm soil profile in different farmlands ranged from 1.27 mg x kg(-1) to 83.60 mg x kg(-1) Soil NO3- -N concentration was higher in 0-40 cm and 135-300 cm layers, but lower in 40-135 cm layer. Greenhouse vegetable field had a significantly higher soil NO3- -N concentration than the other farmland use types. The accumulated amount of soil NO3- -N decreased in the order of greenhouse vegetable field > tomato field > cotton field > seed maize field > maize-wheat rotation field > maize-wheat stripe intercropping field > alfalfa field > jujube plantation. The NO3- -N accumulation in 0-300 cm soil profile in greenhouse vegetable filed reached 2171.45 kg x hm(-2), which would be a serious menace to groundwater quality, followed by tomato field and cotton field. Lesser accumulation of soil NO3- -N was found in seed maize field, maize-wheat intercropping field, maize-wheat rotation field, alfalfa field, and jujube plantation, but its pollution potential would not be neglected. After winter irrigation, soil NO3- -N concentration decreased in 0-80 cm layer but increased in 80-300 cm layer, indicating that winter irrigation caused NO3- -N leaching into deeper soil depth. The leached amount of soil NO3- -N to deeper layers increased with increasing amount of winter irrigation. To mitigate soil NO3- -N leaching and groundwater contamination, a comprehensive consideration should be made on the rational arrangement of farmland use type, proper decrease of planting N-accumulated crops, and reasonable winter irrigation.

  7. Arsenic species and their accumulation features in green turtles (Chelonia mydas).

    PubMed

    Agusa, Tetsuro; Takagi, Kozue; Iwata, Hisato; Tanabe, Shinsuke

    2008-01-01

    Total arsenic (As) and its compounds were determined in liver, kidney, muscle, and stomach contents of green turtles (Chelonia mydas). Total As concentrations in the muscle were higher than those in the kidney and liver. Arsenobetaine (AB) was the predominant compound in all the three tissues and its levels were positively correlated with total As concentrations. This indicates that AB greatly contributes to As accumulation in green turtles. Higher concentrations of remaining As in the sample after extraction were detected in the liver, implying that lipid-soluble or protein bound As compounds accumulate in the liver of green turtles. Total As levels in tissues showed significant negative correlations with standard carapace length. The size-dependence of As accumulation in green turtles may be related to their feeding habit, shifting from carnivore to herbivore at different growth stages. Concentrations of AB and dimethylarsinic acid (DMA) were low in the stomach contents but high in the tissues, implying bioaccumulation of these arsenicals in green turtles. PMID:18291422

  8. Implication of citrate, malate and histidine in the accumulation and transport of nickel in Mesembryanthemum crystallinum and Brassica juncea.

    PubMed

    Amari, Taoufik; Lutts, Stanley; Taamali, Manel; Lucchini, Giorgio; Sacchi, Gian Attilio; Abdelly, Chedly; Ghnaya, Tahar

    2016-04-01

    Citrate, malate and histidine have been involved in many processes including metal tolerance and accumulation in plants. These molecules have been frequently reported to be the potential nickel chelators, which most likely facilitate metal transport through xylem. In this context, we assess here, the relationship between organics acids and histidine content and nickel accumulation in Mesembryanthemum crystallinum and Brassica juncea grown in hydroponic media added with 25, 50 and 100 µM NiCl2. Results showed that M. crystallinum is relatively more tolerant to Ni toxicity than B. juncea. For both species, xylem transport rate of Ni increased with increasing Ni supply. A positive correlation was established between nickel and citrate concentrations in the xylem sap. In the shoot of B. juncea, citric and malic acids concentrations were significantly higher than in the shoot of M. crystallinum. Also, the shoots and roots of B. juncea accumulated much more histidine. In contrast, a higher root citrate concentration was observed in M. crystallinum. These findings suggest a specific involvement of malic and citric acid in Ni translocation and accumulation in M. crystallinum and B. juncea. The high citrate and histidine accumulation especially at 100µM NiCl2, in the roots of M. crystallinum might be among the important factors associated with the tolerance of this halophyte to toxic Ni levels.

  9. Implication of citrate, malate and histidine in the accumulation and transport of nickel in Mesembryanthemum crystallinum and Brassica juncea.

    PubMed

    Amari, Taoufik; Lutts, Stanley; Taamali, Manel; Lucchini, Giorgio; Sacchi, Gian Attilio; Abdelly, Chedly; Ghnaya, Tahar

    2016-04-01

    Citrate, malate and histidine have been involved in many processes including metal tolerance and accumulation in plants. These molecules have been frequently reported to be the potential nickel chelators, which most likely facilitate metal transport through xylem. In this context, we assess here, the relationship between organics acids and histidine content and nickel accumulation in Mesembryanthemum crystallinum and Brassica juncea grown in hydroponic media added with 25, 50 and 100 µM NiCl2. Results showed that M. crystallinum is relatively more tolerant to Ni toxicity than B. juncea. For both species, xylem transport rate of Ni increased with increasing Ni supply. A positive correlation was established between nickel and citrate concentrations in the xylem sap. In the shoot of B. juncea, citric and malic acids concentrations were significantly higher than in the shoot of M. crystallinum. Also, the shoots and roots of B. juncea accumulated much more histidine. In contrast, a higher root citrate concentration was observed in M. crystallinum. These findings suggest a specific involvement of malic and citric acid in Ni translocation and accumulation in M. crystallinum and B. juncea. The high citrate and histidine accumulation especially at 100µM NiCl2, in the roots of M. crystallinum might be among the important factors associated with the tolerance of this halophyte to toxic Ni levels. PMID:26745003

  10. Variations in phthalate ester (PAE) accumulation and their formation mechanism in Chinese flowering cabbage (Brassica parachinensis L.) cultivars grown on PAE-contaminated soils.

    PubMed

    Zhao, Hai-Ming; Du, Huan; Xiang, Lei; Chen, Yi-Liang; Lu, Lei-An; Li, Yan-Wen; Li, Hui; Cai, Quan-Ying; Mo, Ce-Hui

    2015-11-01

    Phthalate ester (PAE) accumulation in crops poses great risks to human health and has aroused great concern. Here, we investigated variations in di-n-butylphthalate (DBP) and di-(2-ethylhexyl) phthalate (DEHP) accumulation by various Chinese flowering cabbage cultivars and revealed their variation mechanism. There were significant differences (p < 0.05) in shoot PAE concentrations of 28 cultivars. Moreover, significant positive correlations between DBP and DEHP concentrations in shoots of all cultivars indicated that they could be taken up simultaneously by various cultivars. Due to the lower translocation factor of low-PAE accumulator, its shoot PAEs concentrations were much lower than root compared to high-PAE accumulator. Further, subcellular distribution showed that PAE concentrations of root cell walls and organelles were much higher than those of shoots in low-PAE accumulator. Therefore, lower translocation from root to shoot and more PAEs accumulating in cell walls and organelles of root might act as main formation mechanism of low-PAE accumulator.

  11. [Characteristics of Number Concentration Size Distributions of Aerosols Under Processes in Beijing].

    PubMed

    Su, Jie; Zhao, Pu-sheng; Chen, Yi-na

    2016-04-15

    The aerosol number concentration size distributions were measured by a Wide-Range Particle Spectrometer (WPS-1000XP) at an urban site of Beijing from 2012 to 2014; and the characteristics of the size distributions in different seasons and weather conditions were discussed. The results showed that the daily average number concentration of Aitken mode aerosols was highest in the spring and lowest in the autumn; the daily average number concentration of accumulation mode aerosols was bigher in the spring and winter, while lowest in summer; and the average concentration of coarse mode was highest during the winter. The Aitken mode particles had the most significant diurnal variations resulted from the traffic sources and the summer photochemical reactions. In the spring, autumn and winter, the number concentrations of accumulation mode of the nighttime was higher than that of the daytime. The coarse mode particles did not have obvious diurnal variation. During the heavy pollution process, the accumulation mode aerosols played a decisive role in PM₂.₅ concentrations and was usually removed by the north wind. The precipitation could effectively eliminate the coarse mode particles, but it bad no obvious effect on the accumulation mode particles under small speed wind and zero speed wind. During the dust process, the concentrations of coarse mode particles increased significantly, while the accumulation mode aerosol concentration was obviously decreased. PMID:27548939

  12. dCTP pyrophosphohydrase exhibits nucleic accumulation in multiple carcinomas.

    PubMed

    Zhang, Y; Ye, W Y; Wang, J Q; Wang, S J; Ji, P; Zhou, G Y; Zhao, G P; Ge, H L; Wang, Y

    2013-09-25

    Nucleoside triphosphate pyrophosphohydrolase (NTP-PPase) functions as one of the mechanisms to guarantee the fidelity of DNA replication through the cleavage of non-canonical nucleotides into di- or monophosphates. Human NTP-PPase is poorly understood and investigated. In the present study, by using tissue microassays with the paired cancer and adjacent regions, we found that with the prevalent expression of dCTP pyrophosphohydrase (DCTPP1) in the cytosol and nucleus in tumors investigated, DCTPP1 was inclined to accumulate in the nucleus of cancer cells compared to the paired adjacent tissue cells in multiple carcinoma including lung, breast, liver, cervical, gastric and esophagus cancer. More significantly, the higher DCTPP1 expression in the nucleus of lung, gastric and esophagus cancer cells was associated with histological subtypes. The nucleic accumulation of DCTPP1 was apparently observed as well when cancer cell line MCF-7 was treated with H2O2 in vitro. Considering the roles of DCTPP1 on restricting the concentration of non-canonical nucleotides in the nucleotide pool, accumulation of DCTPP1 in the nucleus of cancer cells might suffice for maintaining the proper DNA replication in order to fulfill the requirement for the survival and proliferation of tumor cells.

  13. Arsenic accumulation in lichens of Mandav monuments, Dhar district, Madhya Pradesh, India.

    PubMed

    Bajpai, Rajesh; Upreti, D K; Dwivedi, S K

    2009-12-01

    Total arsenic in four different growth forms of lichens growing on old monuments in the city of Mandav, Dhar district of Madhya Pradesh, India was analyzed. Among the different growth forms, foliose lichens were found to accumulate higher amounts of arsenic followed by leprose form. The squamulose and crustose form accumulates the lower concentration of arsenic and ranged between 0.46 +/- 0.03 and 20.99 +/- 0.58 mircog g(-1) dry weight, while the foliose and leprose lichens have ranges from 10.98-51.95 and 28.63-51.20 mircog g(-1) dry weight, respectively. The substrate having high arsenic ranges also exhibit higher ranges of arsenic on lichens growing on them. The cyanolichens exhibit higher concentration of arsenic than the green photobiont-containing squamulose form. The higher concentration of arsenic was found at site having past mining activities. LSD (1%) shows significant difference for As concentration in lichens thallus between the selected sites and species both.

  14. Physiological changes and tissue metal accumulation in rainbow trout exposed to foodborne and waterborne metals

    SciTech Connect

    Farag, A.A.; Boese, C.J.; Bergman, H.L. . Dept. of Zoology and Physiology); Woodward, D.F. )

    1994-12-01

    Sublethal physiological effects and metal residue accumulation in tissues were measured in adult and juvenile rainbow trout fed a metal-contaminated diet and/or exposed to waterborne metals for 21 d. The consumption of metal-contaminated invertebrates from the Clark Fork River, Montana, significantly affected scale loss and metal accumulation in gut tissue of adult trout. Survival, scale loss, and metal accumulation in gill and kidney tissue were affected by exposure to a waterborne mixture of Cd, Cu, and Pb at twice the acceptable levels and Zn at the maximum acceptable level established by the US Environmental Protection Agency for protection of aquatic wildlife. A combination of dietary and waterborne metals also caused lipid peroxidation in the kidney of adult fish and decreased whole-body potassium of juvenile trout. In general, metal accumulation in tissues was higher in gill and kidney with waterborne exposures and was higher in stomach and pyloric caeca with dietary exposure. And metal concentrations in juvenile whole-body tissues accumulated significantly with a combination of waterborne and dietary metals. Although some physiological changes were noted (scale loss, lipid peroxidation of kidney), an exposure time longer than 21 d is probably needed to observe more extensive physiological changes. Regardless, results from this study suggest that a full assessment of metal exposure to fish populations in natural systems must include evaluation of dietary as well as waterborne metal contamination.

  15. Accumulator with preclosing preventer

    SciTech Connect

    Murthy, R.R.; Rice, B.J.

    1981-11-24

    A guided-float accumulator suitable for use with a hydraulic system for an oil well blowout preventer is provided with a wing shut-off valve. Radially inwardly directed outlet parts are aimed at the bottom of the valve wing to generate unbalanced reaction forces which oppose the bernoulli effect forces caused by rapid movement of fluid through the chamber of the shut-off valve, thus preventing premature closing of the valve.

  16. Natural radionuclide accumulation by raindrops

    NASA Astrophysics Data System (ADS)

    Gusev, Anatoly; Martin, Inacio; Shkevov, Rumen; Alves, Mauro

    2016-07-01

    The laboratory of environmental radiation of ITA (São José dos Campos, 23°11'11″S, 45°52'43″W, 650 MAMSL) performs simultaneous monitoring of a natural radiation background and meteorological parameters. A time resolution of up to 1 minute allows a detailed comparison of changes in meteorological parameters with those of a concentration of ambient radon progenies in the atmosphere. Results of a study of variation of a fallout of radon progenies ^{214}Pb and ^{214}Bi concomitanting rainfalls are present. The radionuclide fallout rate is reconstructed from the observed gamma rate through a simulation of the first kind Volterra integral equation with difference kernel, determined by ratio of precipitating rates of 214Pb and 214Bi and their decay half times. An original straightforward step-by-step procedure was used for the numerical solution of the equation. The radionuclide concentration in the rainwater is calculated as a ratio of the reconstructed fallout to the measured rainfall. It was observed that the radionuclide fallout rate increases as the rainfall one in approximately power 0.6, i.e. the same as the mean raindrop volume. The concentration thereafter decreases as the rainfall rate in power 0.4. A numerical simulation of the process of accumulation of the radionuclides during diffusion and coalescence drop growth and aerosol scavenging during a passage from a cloud to the ground was performed. The results of the simulations agree with the experimental data.

  17. Toxicity and accumulation of mercury in three species of crabs with different osmoregulatory capacities

    SciTech Connect

    Bianchini, A.; Gilles, R.

    1996-07-01

    Synergism between mercury and salinity has been shown in invertebrates. Two authors have tied to correlate salinity effects with a higher or lower accumulation of mercury. Zauke, demonstrated lower mercury levels in several benthic invertebrates from limnic regions of the Elbe estuary when compared to those from Marine regions. On the other hand, Kendall did not report any significant difference in mercury concentrations in benthic macroinvertebrates throughout a salinity gradient in two estuaries from Georgia. In species hyperosmoregulating in diluted media, it could, however, be considered that the high water turnover would favor mercury accumulation. In this context, one could also expect a relationship between environmental salinity and mercury toxicity in different euryhaline species depending on their osmoregulatory capacities. We have tested this hypothesis analyzing the toxic effects and accumulation of mercury in three euryhaline crabs presenting different osmoregulatory capacities: Eriocheir sinensis (strong hyperosmoregulator), Carcinus maenas (weak hyperosmoregulator) and Cancer pagurus (osmoconformer). 16 refs., 4 figs., 1 tab.

  18. Distribution and accumulation of hexachlorobutadiene in soils and terrestrial organisms from an agricultural area, East China.

    PubMed

    Tang, Zhenwu; Huang, Qifei; Cheng, Jiali; Qu, Dan; Yang, Yufei; Guo, Wei

    2014-10-01

    Hexachlorobutadiene (HCBD) is a potential persistent organic pollutant that has been found in abiotic environments and organisms. However, information on HCBD in soils and its accumulation in terrestrial food chains is scarce. This study investigated the accumulation of HCBD in soils, plants, and terrestrial fauna in a typical agricultural area in Eastern China, and drew comparisons with organochlorine pesticides (OCPs). The HCBD concentrations in soils were <0.02-3.1ng/g dry weight, which were similar to α-endosulfan concentrations but much lower than the concentrations of some other OCPs. The HCBD soil-plant accumulation factors, 8.5-38.1, were similar to those of o,p'-DDT and higher than those of HCHs and p,p'-DDT, indicating that HCBD is strongly bioaccumulated by rice and vegetables. HCBD concentrations of 1.3-8.2ng/g lipid weight were found in herbivorous insects, earthworms, and Chinese toads. The biomagnification factor, the ratio between the lipid-normalized concentrations in the predator and the prey, was found to be 0.16-0.64 for different food chains of Chinese toads, so HCBD was found not to biomagnify, which is in contrast with OCPs. Further research into whether HCBD is biomagnified in high trophic level organisms or through the entire terrestrial food web is required. PMID:25124679

  19. Variation in arsenic accumulation and translocation among wheat cultivars: the relationship between arsenic accumulation, efflux by wheat roots and arsenate tolerance of wheat seedlings.

    PubMed

    Shi, Gao Ling; Zhu, Shun; Meng, Ji Rong; Qian, Meng; Yang, Na; Lou, Lai Qing; Cai, Qing Sheng

    2015-05-30

    Fifty-seven wheat cultivars were used to investigate the differences in arsenic (As) accumulation, efflux and translocation among wheat cultivars and their relationship with arsenate (As(V)) tolerance under hydroponic condition. The relationship between wheat root As accumulation, As(V) uptake, arsenite (As(III)) efflux and As(V) tolerance of 14 wheat cultivars were also investigated. The results showed there were significant (p<0.001) differences in As(V) tolerance, As accumulation and translocation among 57 wheat cultivars. Arsenate tolerance of wheat seedlings was positively correlated with As(V) uptake (p<0.05), root As concentration (p<0.001), but negatively correlated (p<0.05) with TFs and relative As(III) efflux. No significant correlation between As(III) efflux and As(V) tolerance was found (p=0.442). 56-83% of total As taken up by roots was extruded to nutrient solution. Root As concentration was positively correlated with As(V) uptake (not significant, p=0.100), negatively correlated (p<0.001) with relative As(III) efflux, whereas not significantly correlated (p=0.773) with As(III) efflux. The results indicated that As(V) tolerant wheat cultivars have much higher capacity of root As accumulation. Arsenic detoxification in root cells is important for wheat seedlings under As(V) exposure. PMID:25725341

  20. Higher Education.

    ERIC Educational Resources Information Center

    Hendrickson, Robert M.

    This eighth chapter of "The Yearbook of School Law, 1986" summarizes and analyzes over 330 state and federal court cases litigated in 1985 in which institutions of higher education were involved. Among the topics examined were relationships between postsecondary institutions and various governmental agencies; discrimination in the employment of…

  1. Higher Education.

    ERIC Educational Resources Information Center

    Hendrickson, Robert M.; Gregory, Dennis E.

    Decisions made by federal and state courts during 1983 concerning higher education are reported in this chapter. Issues of employment and the treatment of students underlay the bulk of the litigation. Specific topics addressed in these and other cases included federal authority to enforce regulations against age discrimination and to revoke an…

  2. Higher Education.

    ERIC Educational Resources Information Center

    Hendrickson, Robert M.

    Litigation in 1987 was very brisk with an increase in the number of higher education cases reviewed. Cases discussed in this chapter are organized under four major topics: (1) intergovernmental relations; (2) employees, involving discrimination claims, tenured and nontenured faculty, collective bargaining and denial of employee benefits; (3)…

  3. Higher Education.

    ERIC Educational Resources Information Center

    Hendrickson, Robert M.; Finnegan, Dorothy E.

    The higher education case law in 1988 is extensive. Cases discussed in this chapter are organized under five major topics: (1) intergovernmental relations; (2) employees, involving discrimination claims, tenured and nontenured faculty, collective bargaining, and denial of employee benefits; (3) students, involving admissions, financial aid, First…

  4. Higher Learning.

    ERIC Educational Resources Information Center

    Bok, Derek

    Factors that distinguish the United States higher education system and its performance are considered, with attention to new developments, propsects for change, undergraduate education, and professional schools (especially law, business, and medicine). The way universities change the methods and content of their teaching in response to new…

  5. Selenium accumulation in flowers and its effects on pollination.

    PubMed

    Quinn, Colin F; Prins, Christine N; Freeman, John L; Gross, Amanda M; Hantzis, Laura J; Reynolds, Ray J B; Yang, Soo in; Covey, Paul A; Bañuelos, Gary S; Pickering, Ingrid J; Fakra, Sirine C; Marcus, Matthew A; Arathi, H S; Pilon-Smits, Elizabeth A H

    2011-11-01

    • Selenium (Se) hyperaccumulation has a profound effect on plant-arthropod interactions. Here, we investigated floral Se distribution and speciation in flowers and the effects of floral Se on pollen quality and plant-pollinator interactions. • Floral Se distribution and speciation were compared in Stanleya pinnata, an Se hyperaccumulator, and Brassica juncea, a comparable nonhyperaccumulator. Pollen germination was measured from plants grown with varying concentrations of Se and floral visitation was compared between plants with high and low Se. • Stanleya pinnata preferentially allocated Se to flowers, as nontoxic methyl-selenocysteine (MeSeCys). Brassica juncea had higher Se concentrations in leaves than flowers, and a lower fraction of MeSeCys. For B. juncea, high floral Se concentration impaired pollen germination; in S. pinnata Se had no effect on pollen germination. Floral visitors collected from Se-rich S. pinnata contained up to 270 μg g(-1), concentrations toxic to many herbivores. Indeed, floral visitors showed no visitation preference between high- and low-Se plants. Honey from seleniferous areas contained 0.4-1 μg Se g(-1), concentrations that could provide human health benefits. • This study is the first to shed light on the possible evolutionary cost, through decreased pollen germination in B. juncea, of Se accumulation and has implications for the management of seleniferous areas. PMID:21793829

  6. PCB concentrations of lake whitefish (Coregonus clupeaformis) vary by sex

    USGS Publications Warehouse

    Madenjian, Charles P.; Ebener, Mark P.; Sepulveda, Maria S.

    2015-01-01

    We determined whole-fish polychlorinated biphenyl (PCB) concentrations in 26 female lake whitefish (Coregonus clupeaformis) and 34 male lake whitefish from northern Lake Huron. In 5 of the 26 female lake whitefish, we also determined PCB concentrations in the somatic tissue and ovaries. In addition, bioenergetics modeling was used to determine the contribution of the growth dilution effect to the observed difference in PCB concentrations between the sexes. Whole-fish PCB concentrations for females and males averaged 60 ng/g and 80 ng/g, respectively; thus males were 34% higher in PCB concentration compared with females. Based on the PCB determinations in the somatic tissue and ovaries, we predicted that PCB concentration of females would increase by 2.5%, on average, immediately after spawning due to release of eggs. Thus, the change in PCB concentration due to release of eggs did not explain, to any degree, the higher PCB concentrations observed in males compared with females. Bioenergetics modeling results indicated that the growth dilution effect could account for males being only 0.7% higher in PCB concentration compared with females. Thus, the growth dilution effect contributed very little to the observed difference in PCB concentrations between the sexes. We conclude that males were higher than females in PCB concentration most likely due to a higher rate of energy expenditure, stemming from greater activity and a greater resting metabolic rate. A higher rate of energy expenditure leads to a higher rate of food consumption, which, in turn, leads to a higher PCB accumulation rate.

  7. Accumulation of Pb, Cd, Cu and Zn in plants and hyperaccumulator choice in Lanping lead-zinc mine area, China.

    PubMed

    Yanqun, Zu; Yuan, Li; Schvartz, Christian; Langlade, Laurent; Fan, Liu

    2004-06-01

    A field survey of higher terrestrial plants growing on Lanping lead-zinc mine, China were conducted to identify species accumulating exceptionally large concentrations of Pb, Cd, Cu and Zn of 20 samples of 17 plant species. Concentrations of Pb and Zn in soil and in plant were higher than that of Cu and Cd. Significant difference was observed among the average concentrations of four heavy metals in plants (except Cd and Cu) and in soil (except Pb and Zn) (P<0.05). For the enrichment coefficient of the four heavy metals in plant, the order of average was Pbhigher than 1 in Llex plyneura and Rhododendron annae in Paomaping for Pb, Salix cathayana, L. plyneura and R. annae in Paomaping for Cd, and R. annae in Paomaping for Zn, respectively. Concentrations and enrichment coefficient of Pb, Cd and Zn of Rhododendron were higher than that of Gramimeae. Enrichment coefficient of Pb, Cd and Zn were bush>tree>herbaceous, and herbaceous grew in soil with the highest concentrations of four heavy metals. In different areas, the concentrations of Pb, Cd, Cu and Zn in plants and soils and enrichment coefficient were different. Plants in Paomaping had more accumulating ability to Pb, Cd and Zn, and plants in Jinfeng River had more accumulating ability to Cu. Six plant species, i.e. S. cathayana, Lithocarpus dealbatus, L. plyneura, Fargesia dura, Arundinella yunnanensis and R. annae in Paomaping, had high accumulation capacity. R. annae in Paomaping had hyperaccumulating capacity to Pb, Cd and Zn, L. plyneura to Pb and Cd, and S. cathayana to Cd, respectively. PMID:15031017

  8. Lead accumulation potential in Acacia victoria.

    PubMed

    Mahdavi, Ali; Khermandar, Khadijeh; Asbchin, Salman Ahmady; Tabaraki, Reza

    2014-01-01

    To assess the potential of Pb+2 accumulation in different parts of Acacia victoria, one year old A. victoria seedlings were exposed to Pb2+(NO3)2 in 5 different concentrations: 0, 50, 250, 500 and 1000 (mg Pb2+ L(-1)) for 45 days. Subsequently, Pb2+ uptake was quantified in roots, shoots and leaves of the seedlings by Atomic Absorption Spectroscopy (AAS). In addition, some physiological parameters such as biomass production, shoots and roots length, plant appearance, tissue concentrations and chlorophyll content were examined. Tissue concentrations increased as Pb2+ concentration increased for A. victoria. The visible toxicity symptoms (chlorosis and necrosis) appeared only to the highest concentration (1000 mg Pb2+ L(-1)), resulting in photosynthesis decrease, plant height, root length and dry biomass reduction. Almost 70% (up to 3580 mg Kg(-1) of dry tissue) from the Pb2+ was accumulated in the entire plant tissues was retained in the roots in the seedlings exposed to 1000 mg Pb2+ L(-1). The seedlings accumulated between 403 to 913 mg Kg(-1) of Pb2+ in shoots and 286 to 650 mg Kg(-1) of Pb2+ in leaves at different treatments. Bioconcentration and translocation factors were determined 5.14 and 0.255, respectively. The results show that A. victoria is suitable for lead-phytostabilization in Pb(2+) -contaminated soil.

  9. Uptake and concentration factor af Aroclor 1254 in aquatic organisms

    SciTech Connect

    Gooch, J.A.; Hamdy, M.K.

    1983-10-01

    There are several factors that affect PCB bioaccumulation. These include: concentration in the surrounding environment; duration of exposure; temperature; solubility of the pollutant; species age, weight, feeding habits and lipid content; trophic level variations; and adsorption. Bioaccumulation can occur either through ingestion of contaminated food organisms or by direct absorption through the integument. Higher concentrations of PCBs have been found in plankton than in fish, indicating that direct absorption is the primary route of accumulation. This investigation was conducted to follow the uptake and concentration factor (CF) of Aroclor 1254 in selected organisms representing a simple aquatic ecosystem.

  10. Selenium accumulation in sea ducks wintering at Lake Ontario.

    PubMed

    Schummer, Michael L; Badzinski, Shannon S; Petrie, Scott A; Chen, Yu-Wei; Belzile, Nelson

    2010-04-01

    Numbers of wintering sea ducks, including buffleheads (Bucephala albeola; BUFF), common goldeneyes (Bucephala clangula; COGO), and long-tailed ducks (Clangula hyemalis; LTDU), increased substantially at Lake Ontario after Dreissenid mussels (Dreissena bugensis and D. polymorpha) colonized the Great Lakes. Invertebrates, including Dreissenid mussels, are major diving duck prey items that can transfer some trace elements, such as selenium (Se) to higher trophic levels. Se can be problematic for waterfowl and it often has been detected at elevated levels in organisms using the Great Lakes. There are, however, few data on hepatic Se concentrations in sea ducks, particularly during the winter at Lake Ontario. In this study, we evaluated interspecific differences and temporal trends in hepatic Se concentrations among BUFF (n = 77), COGO (n = 77), and LTDU (n = 79) wintering at Lake Ontario. All three species accumulated Se throughout winter, but COGO did so at a higher rate than did BUFF and LTDU. Overall, Se concentrations were higher in LTDU [mean = 22.7; 95% CI = 20.8-24.8 microg/g dry weight (dw)] than in BUFF ([mean = 12.3; 95% CI = 11.6-13.1 microg/g dw) and COGO ([mean = 12.0; 95% CI = 10.7-3.5 microg/g dw) throughout the winter. Se concentrations were deemed elevated (>33 microg/g dw) in 0%, 5%, and 19% of BUFF, COGO, and LTDU, respectively. Presently there are no data on Se toxicity end points for these species, so it is unclear how acquiring concentrations of these magnitudes affect their short- and long-term health or reproduction. PMID:19653029

  11. Phytotoxicity, accumulation and transport of silver nanoparticles by Arabidopsis thaliana.

    PubMed

    Geisler-Lee, Jane; Wang, Qiang; Yao, Ying; Zhang, Wen; Geisler, Matt; Li, Kungang; Huang, Ying; Chen, Yongsheng; Kolmakov, Andrei; Ma, Xingmao

    2013-05-01

    The widespread availability of nano-enabled products in the global market may lead to the release of a substantial amount of engineered nanoparticles in the environment, which frequently display drastically different physiochemical properties than their bulk counterparts. The purpose of the study was to evaluate the impact of citrate-stabilised silver nanoparticles (AgNPs) on the plant Arabidopsis thaliana at three levels, physiological phytotoxicity, cellular accumulation and subcellular transport of AgNPs. The monodisperse AgNPs of three different sizes (20, 40 and 80 nm) aggregated into much larger sizes after mixing with quarter-strength Hoagland solution and became polydisperse. Immersion in AgNP suspension inhibited seedling root elongation and demonstrated a linear dose-response relationship within the tested concentration range. The phytotoxic effect of AgNPs could not be fully explained by the released silver ions. Plants exposed to AgNP suspensions bioaccumulated higher silver content than plants exposed to AgNO3 solutions (Ag(+) representative), indicating AgNP uptake by plants. AgNP toxicity was size and concentration dependent. AgNPs accumulated progressively in this sequence: border cells, root cap, columella and columella initials. AgNPs were apoplastically transported in the cell wall and found aggregated at plasmodesmata. In all the three levels studied, AgNP impacts differed from equivalent dosages of AgNO3.

  12. Plants use macronutrients accumulated in leaf-cutting ant nests

    PubMed Central

    da S.L Sternberg, Leonel; Pinzon, Maria Camila; Moreira, Marcelo Z; Moutinho, Paulo; Rojas, Enith I; Herre, Edward Allen

    2006-01-01

    Leaf-cutting ants (Atta spp.) are known for their extensive defoliation in neo-tropical forests and savannahs. Debate about the costs and benefits of their activities has been largely dominated by their detrimental effects on agriculture and agroforestry. However, the large accumulation of nutrients and changes in soil properties near their nests might benefit plants growing near them. Here, we test whether trees use nutrients that accumulate in debris piles near, or refuse chambers within, leaf-cutting ant nests. At two tropical sites (a moist tropical forest site in Panama and a savannah site in Brazil), we fed leaves labelled with the stable isotope 15N to two species of leaf-cutting ants (Atta colombica and Atta laevigata) and traced the stable isotope label in plants surrounding the two nests. Thus, we show that plants in both sites access resources associated with Atta nests. In addition, leaf tissue of trees near the nests labelled with 15N had significantly higher calcium concentrations than those of distal, unlabelled conspecifics. It has been documented that calcium is a limiting macronutrient in tropical forests and savannahs. Atta may thus play an important ecological role through their long-distance transport, redistribution and concentration of critical macronutrients. PMID:17164194

  13. Variation in selenium tolerance and accumulation among 19 Arabidopsis thaliana accessions.

    PubMed

    Zhang, Lihong; Ackley, Ashley R; Pilon-Smits, Elizabeth A H

    2007-03-01

    Selenium (Se) is an essential element for many organisms but also toxic at higher levels. The objective of this study was to identify accessions from the model species Arabidopsis thaliana that differ in Se tolerance and accumulation. Nineteen Arabidopsis accessions were grown from seed on agar medium with or without selenate (50 microM) or selenite (20 microM), followed by analysis of Se tolerance and accumulation. Tissue sulfur levels were also compared. The Se Tolerance Index (root length+Se/root length control) varied among the accessions from 0.11 to 0.44 for selenite and from 0.05 to 0.24 for selenate. When treated with selenite, the accessions differed by two-fold in shoot Se concentration (up to 250 mgkg(-1)) and three-fold in root Se concentration (up to 1000 mgkg(-1)). Selenium accumulation from selenate varied 1.7-fold in shoot (up to 1000 mgkg(-1)) and two-fold in root (up to 650 mgkg(-1)). Across all accessions, a strong correlation was observed between Se and S concentration in both shoot and root under selenate treatment, and in roots of selenite-treated plants. Shoot Se accumulation from selenate and selenite were also correlated. There was no correlation between Se tolerance and accumulation, either for selenate or selenite. The F(1) offspring from a cross between the extreme selenate-sensitive Dijon G and the extreme selenate-tolerant Estland accessions showed intermediate selenate tolerance. In contrast, the F(1) offspring from a cross between selenite-sensitive and -tolerant accessions (Dijon GxCol-PRL) were selenite tolerant. The results from this study give new insight into the mechanisms of plant selenium (Se) tolerance and accumulation, which may help develop better plants for selenium phytoremediation or as fortified foods. PMID:16513208

  14. PBDE and PCB accumulation in benthos near marine wastewater outfalls: the role of sediment organic carbon.

    PubMed

    Dinn, Pamela M; Johannessen, Sophia C; Ross, Peter S; Macdonald, Robie W; Whiticar, Michael J; Lowe, Christopher J; van Roodselaar, Albert

    2012-12-01

    Polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) were measured in sediments and benthic invertebrates near submarine municipal outfalls in Victoria and Vancouver, B.C., Canada, two areas with contrasting receiving environments. PBDE concentrations in wastewater exceeded those of the legacy PCBs by eight times at Vancouver and 35 times at Victoria. Total PBDE concentrations in benthic invertebrates were higher near Vancouver than Victoria, despite lower concentrations in sediments, and correlated with organic carbon-normalized concentrations in sediment. Principal Components Analysis indicated uptake of individual PBDE congeners was determined by sediment properties (organic carbon, grain size), while PCB congener uptake was governed by physico-chemical properties (octanol-water partitioning coefficient). Results suggest the utility of sediment quality guidelines for PBDEs and likely PCBs benefit if based on organic carbon-normalized concentrations. Also, where enhanced wastewater treatment increases the PBDEs to particulate organic carbon ratio in effluent, nearfield benthic invertebrates may face increased PBDE accumulation.

  15. Accumulation, distribution, and speciation of arsenic in wheat grain.

    PubMed

    Zhao, Fang-Jie; Stroud, Jacqueline L; Eagling, Tristan; Dunham, Sarah J; McGrath, Steve P; Shewry, Peter R

    2010-07-15

    Food can be an important source of inorganic As for human intake. Recent studies have focused on rice, while little information is available on As accumulation, distribution, and speciation in wheat, which is the second most important food grain cereal. Grain samples of 26 wheat cultivars grown in five field trials located in productive farming regions in Europe were therefore analyzed for As concentration and speciation. Grain from four trials contained low concentrations of total As (7.7 +/- 5.4 microg kg(-1)), reflecting low levels of As in the soils (1.3-11 mg kg(-1)). In contrast, at one of the trial sites the As level in the soil was greater (29 mg kg(-1)), and much higher As concentrations (69 +/- 17 microg kg(-1)) were present in the wheat grain. Milling of wheat grain into bran and white flour fraction showed the concentration of As in the bran, with a 3.8-4.7-fold higher As concentration than in the white flour. Two methods (a phosphate buffer solution and 1% HNO(3)) were used to extract As species from wholemeal, bran, and white flour of wheat, with average extraction efficiencies of 65% and 88%, respectively. Only inorganic As was found in the extracts, with no methylated As being detected. The contribution of wheat to human intake of inorganic As is small for wheat crops grown in uncontaminated soils but becomes significant for those grown in soils with elevated As. In the latter case, milling can be used to reduce the As concentration in the white flour. PMID:20578703

  16. Heat exchanger-accumulator

    DOEpatents

    Ecker, Amir L.

    1980-01-01

    What is disclosed is a heat exchanger-accumulator for vaporizing a refrigerant or the like, characterized by an upright pressure vessel having a top, bottom and side walls; an inlet conduit eccentrically and sealingly penetrating through the top; a tubular overflow chamber disposed within the vessel and sealingly connected with the bottom so as to define an annular outer volumetric chamber for receiving refrigerant; a heat transfer coil disposed in the outer volumetric chamber for vaporizing the liquid refrigerant that accumulates there; the heat transfer coil defining a passageway for circulating an externally supplied heat exchange fluid; transferring heat efficiently from the fluid; and freely allowing vaporized refrigerant to escape upwardly from the liquid refrigerant; and a refrigerant discharge conduit penetrating sealingly through the top and traversing substantially the length of the pressurized vessel downwardly and upwardly such that its inlet is near the top of the pressurized vessel so as to provide a means for transporting refrigerant vapor from the vessel. The refrigerant discharge conduit has metering orifices, or passageways, penetrating laterally through its walls near the bottom, communicating respectively interiorly and exteriorly of the overflow chamber for controllably carrying small amounts of liquid refrigerant and oil to the effluent stream of refrigerant gas.

  17. Amino acid concentrations in human embryological fluids.

    PubMed

    Jauniaux, E; Sherwood, R A; Jurkovic, D; Boa, F G; Campbell, S

    1994-06-01

    The concentrations of amino acids in samples of coelomic fluid (n = 15), amniotic fluid (n = 9) and maternal serum (n = 15) obtained from normal pregnancies between 7 and 12 weeks of gestation were measured using reversed-phase chromatography with pre-column derivatization. The total molar concentration of the 18 amino acids measured was 2.3 times higher in coelomic fluid than in maternal serum. All amino acids except serine and tryptophan were present in significantly higher concentrations in coelomic fluid than in maternal serum. Significant correlations between maternal serum and coelomic fluid were only found for proline, tyrosine, and tryptophan, suggesting that levels of the other amino acids are mainly influenced by placental synthesis and do not directly depend on maternal amino acid metabolism. Levels of all amino acids were significantly higher in coelomic fluid compared to amniotic fluid. Compared to maternal serum, the amniotic fluid contained significantly higher levels of arginine, lysine, alanine and tyrosine and lower levels of serine, glutamine and tryptophan. The total molar amino acid concentration decreased significantly with gestational age in both coelomic fluid and maternal serum. These results suggest that amino acids accumulate in coelomic fluid to support the metabolism of the secondary yolk sac, and that the exocoelomic cavity is the reservoir for most nutrients needed by the embryo and early fetus in the first trimester of human pregnancy.

  18. Effects of water deficit on radicle apex elongation and solute accumulation in Zea mays L.

    PubMed

    Velázquez-Márquez, S; Conde-Martínez, V; Trejo, C; Delgado-Alvarado, A; Carballo, A; Suárez, R; Mascorro, J O; Trujillo, A R

    2015-11-01

    In this study, we examined the effects of water deficit on the elongation of radicles of maize seedlings and on the accumulation of solutes in the radicle apices of two maize varieties: VS-22 (tolerant) and AMCCG-2 (susceptible). Sections of radicle corresponding to the first 2 mm of the primary roots were marked with black ink, and the seedlings were allowed to grow for 24, 48, and 72 h in polyvinyl chloride (PVC) tubes filled with vermiculite at three different water potentials (Ψ(w), -0.03, -1.0, and -1.5 MPa). The radicle elongation, sugar accumulation, and proline accumulation were determined after each of the growth periods specified above. The Ψ(w) of the substrate affected the dynamics of primary root elongation in both varieties. In particular, the lowest Ψ(w) (-1.5 MPa) inhibited root development by 72% and 90% for the VS-22 and AMCCG-2 varieties, respectively. The osmotic potential (Ψ(o)) was reduced substantially in both varieties to maintain root turgor; however, VS-22 had a higher root turgor (0.67 MPa) than AMCCG-2 (0.2 MPa). These results suggest that both varieties possess a capacity for osmotic adjustment. Sugar began to accumulate within the first 24 h of radicle apex growth. The sugar concentration was higher in VS-22 root apices compared to AMCCG-2, and the amount of sugar accumulation increased with a decrease in Ψ(w). Significant amounts of trehalose accumulated in VS-22 and AMCCG-2 (29.8 μmol/g fresh weight [FW] and 5.24 μmol/g FW, respectively). Starch accumulation in the root apices of these two maize varieties also differed significantly, with a lower level in VS-22. In both varieties, the proline concentration also increased as a consequence of the water deficit. At 72 h, the proline concentration in VS-22 (16.2 μmol/g FW) was almost 3 times greater than that in AMCCG-2 (5.19 μmol/g FW). Trehalose also showed a 3-fold increase in the tolerant variety. Accumulation of these solutes in the root growth zone may indicate an osmotic

  19. Which Factors Determine Metal Accumulation in Agricultural Soils in the Severely Human-Coupled Ecosystem?

    PubMed Central

    Xu, Li; Cao, Shanshan; Wang, Jihua; Lu, Anxiang

    2016-01-01

    Agricultural soil is typically an important component of urban ecosystems, contributing directly or indirectly to the general quality of human life. To understand which factors influence metal accumulation in agricultural soils in urban ecosystems is becoming increasingly important. Land use, soil type and urbanization indicators all account for considerable differences in metal accumulation in agricultural soils, and the interactions between these factors on metal concentrations were also examined. Results showed that Zn, Cu, and Cd concentrations varied significantly among different land use types. Concentrations of all metals, except for Cd, were higher in calcareous cinnamon soil than in fluvo-aquic soil. Expansion distance and road density were adopted as urbanization indicators, and distance from the urban center was significantly negatively correlated with concentrations of Hg, and negatively correlated with concentrations of Zn, and road density was positively correlated with Cd concentrations. Multivariate analysis of variance indicated that Hg concentration was significantly influenced by the four-way interaction among all factors. The results in this study provide basic data to support the management of agricultural soils and to help policy makers to plan ahead in Beijing. PMID:27196922

  20. [Relationships between cadmium accumulation and organic acids in leaves of Solanum nigrum L. as a cadmium-hyperaccumulator].

    PubMed

    Sun, Rui-lian; Zhou, Qi-xing; Wang, Xin

    2006-04-01

    The influence of different cadmium concentrations on the organic acid level in leaves of the Cd hyperaccumulator, Solanum nigrum L., in particular, the relationship of organic acids with Cd accumulation in S. nigrum was investigated based on the pot-culture experiment. The results showed that the Cd concentration in S. nigrum leaves exceeded 100 microg x g(-1), the threshold value used to define Cd-hyperaccumulators, and the bioaccumulation coefficient of cadmium in shoots of S. nigrum was higher than 1 when Cd concentration in soil was 25 microg x g(-1). The level of organic acids in leaves of S. nigrum had significant differences between the seedling stage and the mature stage. At the seedling stage, the sequence of organic acids in leaves of S. nigrum was acetic acid> tartaric acid> malic acid> citric acid. On the contrary, the accumulation of organic acids in S. nigrum at the mature stage was approximately in the following sequence malic acid> tartaric acid, acetic acid> citric acid. The significant positive correlation between Cd accumulation in leaves of S. nigrum and the concentration of tartaric acid in leaves of S. nigrum was observed at the seedling stage, whereas there was a significant positive correlation between Cd accumulation in leaves of S. nigrum and both acetic and citric acid concentrations at the mature stage. These results indicated that tartaric, acetic and citric acids in leaves of S. nigrum might act as the indication of Cd hyperaccumulation. PMID:16768003

  1. Sediment accumulation and mercury (Hg) flux in Avicennia marina forest of Deep Bay, China

    NASA Astrophysics Data System (ADS)

    Li, Ruili; Chai, Minwei; Guo, Meixian; Qiu, Guo Yu

    2016-08-01

    To investigate the rate of sediment accumulation and mercury (Hg) flux in Avicennia marina forest of Deep Bay, China, sediment cores were analyzed. The results showed that Hg concentrations were much higher at all depths compared to the background level. A high correlation between Hg and total organic carbon (TOC) indicated their similar anthropogenic origin. Sedimentation rate was estimated to be 1.38 cm a-1 by 210Pb geochronology. The increase in the mass sediment accumulation rates was rapid (range: 0.5-0.94 g cm-2 a-1), and the Hg fluxes ranged between 76 and 116 ng cm-2 a-1 during the last three decades. The reduction in both Hg concentrations and flux during the last decade may be due to the adoption of contamination control policies. Our results support the notion that the Hg fluxes determined from the sediment cores reveal the effects of anthropogenic influences from the areas around Deep Bay.

  2. Sorbitol accumulation in male and female rats consuming starch or fructose diets with or without copper

    SciTech Connect

    Lewis, C.G.; Fields, M.; Beal, T. )

    1989-02-09

    The present study was designed to examine the relationship between the sex of the rats, tissue sorbitol accumulation and copper deficiency in rats consuming dietary fructose. Rats were provided with a diet containing either 62.7% fructose or starch, and either 6.0 or 0.6 {mu}g copper/g for three weeks. Hepatic copper concentration of all rats consuming the copper-deficient diets was about 40% of copper sufficient rats. Hepatic, renal and thymic sorbitol concentrations were significantly elevated in males consuming the fructose, copper-deficient diet when compared to all other dietary groups regardless of the sex of the rat. Hepatic, renal the thymic fructose concentrations were significantly higher in rats eating fructose as compared to female rats. Hepatic glucose concentration was higher in males and females consuming the fructose, copper-deficient diet when compared to all other dietary groups. Renal glucose concentration was elevated in males as compared to females. These results demonstrate that the pathology and complications of copper deficiency in the male rat consuming fructose closely parallel aberration in tissue sorbitol accumulation.

  3. The influence of sedimentation on metal accumulation and cellular oxidative stress markers in the Antarctic bivalve Laternula elliptica

    NASA Astrophysics Data System (ADS)

    Husmann, G.; Abele, D.; Monien, D.; Monien, P.; Kriews, M.; Philipp, E. E. R.

    2012-10-01

    Recent rapid climate warming at the western Antarctic Peninsula (WAP) results in elevated glacial melting, enhanced sedimentary run-off, increased turbidity and impact of ice-scouring in shallow coastal areas. Discharge of mineral suspension from volcanic bedrock ablation and chronic physical disturbance is expected to influence sessile filter feeders such as the Antarctic soft shell clam Laternula elliptica (King and Broderip, 1832). We investigated effects of sedimentary run-off on the accumulation of trace metals, and together with physical disturbance, the cumulative effect on oxidative stress parameters in younger and older L. elliptica from two stations in Potter Cove (King George Island, Antarctica) which are distinctly impacted by turbidity and ice-scouring. Fe, Mn, Sr, V and Zn concentrations were slightly higher in sediments of the station receiving more sediment run-off, but not enriched in bivalves of this station. The only element that increased in bivalves experimentally exposed to sediment suspension for 28 days was Mn. Concentration of the waste accumulation biomarker lipofuscin in nervous tissue was higher in L. elliptica from the “exposed” compared to the “less exposed” site, whereas protein carbonyl levels in bivalve mantle tissue were higher at the less sediment impacted site. Tissue metal content and lipofuscin in nervous tissue were generally higher in older compared to younger individuals from both field stations. We conclude that elevated sediment ablation does not per se result in higher metal accumulation in L. elliptica. Instead of direct absorbance from sediment particles, metal accumulation in gills seems to indicate uptake of compounds dissolved in the water column, whereas metals in digestive gland appear to originate from enriched planktonic or detritic food. Accumulation of cellular waste products and potentially reactive metals over lifetime presumably alters L. elliptica physiological performance with age and may

  4. Carotenogenic gene expression and carotenoid accumulation in three varieties of Cucurbita pepo during fruit development.

    PubMed

    Obrero, Ángeles; González-Verdejo, Clara I; Die, Jose V; Gómez, Pedro; Del Río-Celestino, Mercedes; Román, Belén

    2013-07-01

    The control of gene expression is a crucial regulatory mechanism in carotenoid accumulation of fruits and flowers. We investigated the role of transcriptional regulation of nine genes involved in the carotenoid biosynthesis pathway in three varieties of Cucurbita pepo with evident differences in fruit color. The transcriptional levels of the key genes involved in the carotenoid biosynthesis were higher in flower-, leaf-, and fruit skin tissues than flesh tissues. This correlated with higher concentration of carotenoid content in these tissues. The differential expression among the colored and white cultivars detected for some genes, such as LCYe, in combination with other regulatory mechanisms, could explain the large differences found in terms of carotenoid content among the three varieties. These results are a first step to elucidate carotenogenesis in C. pepo and demonstrate that, in general, regulation of the pathway genes is a critical factor that determines the accumulation of these compounds.

  5. Germanium and Rare Earth Element accumulation in woody bioenergy crops

    NASA Astrophysics Data System (ADS)

    Hentschel, Werner

    2016-04-01

    Germanium and REEs are strategic elements that are used for high tech devices and engineered systems, however these elements are hardly concentrated into mineable ore deposits. Since these elements occur widely dispersed in the earth crust with concentrations of several mgṡkg‑1 (Ge 1.6 mgṡkg‑1, Nd 25 mgṡkg‑1) a new possibility to gain these elements could be phytomining, a technique that uses plants to extract elements from soils via their roots. Since knowledge about accumulating plant species is quite limited we conducted research on the concentrations of strategic elements in wood and leaves of fast growing tree species (Salix spec., Populus spec., Betula pendula, Alnus glutinosa, Fraxinus excelsior, Acer pseudoplatanus). In total 35 study sites were selected in the mining affected area around Freiberg (Saxony, Germany), differing in their species composition and degree of contamination with toxic trace metals (Pb, As, Cd). On each site plant tissues (wood and leaves, respectively) of different species were sampled. In addition soil samples were taken from a soil depth of 0 - 30 cm and 30 - 60 cm. The aim of our work was to investigate correlations between the concentrations of the target elements in plant tissues and soil characteristics like pH, texture, nutrients and concentrations in six operationally defined soil fractions (mobile, acid soluble, oxidizable, amorphic oxides, crystalline oxides, residual or siliceous). Concentrations of elements in soil extracts and plant tissues were measured with ICP-MS. The element Nd was selected as representative for the group of REEs, since this element showed a high correlation with the concentrations of the other REE We found that the concentration of Nd in the leaves (0.31 mgṡkg‑1Nd) were several times higher than in herbaceous species (0.05 mgṡkg‑1 Nd). The concentration of Ge in leaves were ten times lower than that of Nd whereas in herbaceous species Nd and Ge were in equal magnitude. Within

  6. Germanium and Rare Earth Element accumulation in woody bioenergy crops

    NASA Astrophysics Data System (ADS)

    Hentschel, Werner

    2016-04-01

    Germanium and REEs are strategic elements that are used for high tech devices and engineered systems, however these elements are hardly concentrated into mineable ore deposits. Since these elements occur widely dispersed in the earth crust with concentrations of several mgṡkg-1 (Ge 1.6 mgṡkg-1, Nd 25 mgṡkg-1) a new possibility to gain these elements could be phytomining, a technique that uses plants to extract elements from soils via their roots. Since knowledge about accumulating plant species is quite limited we conducted research on the concentrations of strategic elements in wood and leaves of fast growing tree species (Salix spec., Populus spec., Betula pendula, Alnus glutinosa, Fraxinus excelsior, Acer pseudoplatanus). In total 35 study sites were selected in the mining affected area around Freiberg (Saxony, Germany), differing in their species composition and degree of contamination with toxic trace metals (Pb, As, Cd). On each site plant tissues (wood and leaves, respectively) of different species were sampled. In addition soil samples were taken from a soil depth of 0 - 30 cm and 30 - 60 cm. The aim of our work was to investigate correlations between the concentrations of the target elements in plant tissues and soil characteristics like pH, texture, nutrients and concentrations in six operationally defined soil fractions (mobile, acid soluble, oxidizable, amorphic oxides, crystalline oxides, residual or siliceous). Concentrations of elements in soil extracts and plant tissues were measured with ICP-MS. The element Nd was selected as representative for the group of REEs, since this element showed a high correlation with the concentrations of the other REE We found that the concentration of Nd in the leaves (0.31 mgṡkg-1Nd) were several times higher than in herbaceous species (0.05 mgṡkg-1 Nd). The concentration of Ge in leaves were ten times lower than that of Nd whereas in herbaceous species Nd and Ge were in equal magnitude. Within the tree

  7. Bicarbonate trigger for inducing lipid accumulation in algal systems

    SciTech Connect

    Gardner, Robert; Peyton, Brent; Cooksey, Keith E.

    2015-08-04

    The present invention provides bicarbonate containing and/or bicarbonate-producing compositions and methods to induce lipid accumulation in an algae growth system, wherein the algae growth system is under light-dark cycling condition. By adding said compositions at a specific growth stage, said methods lead to much higher lipid accumulation and/or significantly reduced total time required for accumulating lipid in the algae growth system.

  8. Zinc accumulation in fiddler crabs Uca annulipes latreille and Uca triangularis (Milne Edwards)

    SciTech Connect

    Uma Devi, V.; Rao, Y.P. )

    1989-10-01

    The effect of exposure time and concentration on the tissue-specific accumulation of Zn in two fiddler crabs, Uca annulipes and Uca triangularis, obtained from polluted (Visakhapatnam Harbor) and unpolluted (Bhimilipatnam) areas was studied. Hepatopancreas registered major accumulation of Zn when the crabs were exposed to sublethal concentrations (6.38 to 15.39 ppm) for 30 days. However, when the crabs were exposed to different concentrations of Zn (LCO, LC25, LC50, LC75) ranging from 12.93 to 99.38 ppm, higher accumulation was recorded in gills than in hepatopancreas. There was a progressive increase in the percentage body burden of Zn in hepatopancreas, but that in gills showed a decreasing trend. The standardized body burdens for both species of crabs were calculated to evaluate their sensitivity to exposure time as well as to concentration. The fractional retention coefficients for exposure time estimated for exposed crabs indicate that U. triangularis from Bhimilipatnam, having the highest value, is sensitive and U. annulipes from Visakhapatnam Harbor, showing the lowest value, is resistant.

  9. Two-Compartment Kinetic Modeling of Radiocesium Accumulation in Marine Bivalves under Hypothetical Exposure Regimes.

    PubMed

    Pan, Ke; Tan, Qiao-Guo; Wang, Wen-Xiong

    2016-03-01

    Interpreting the variable concentrations of (137)Cs in the field biological samples requires mechanistic understanding of both environmental and biological behavior of (137)Cs. In this study, we used a two-compartment model to estimate and compare the (137)Cs biokinetics in three species of subtropical marine bivalves. Significant interspecific difference of (137)Cs biokinetics was observed among oysters, mussels, and scallops. There was considerable (137)Cs assimilation from phytoplankton in the bivalves, but the calculated trophic transfer factors were generally between 0.04 and 0.4. We demonstrated a major efflux of radiocesium in the scallops (with a rate constant of 0.207 d(-1)), whereas the efflux was comparable between oysters and mussels (0.035-0.038 d(-1)). A two-compartment kinetic model was developed to simulate the (137)Cs accumulation in the three bivalves under four hypothetical exposure regimes. We showed that the bivalves respond differently to the exposure regimes in terms of time to reach equilibrium, equilibrium concentration, and maximum concentration. Bivalves suffering more frequent intermittent exposure may have higher maximum concentrations than those receiving less frequent exposure. The interspecific difference of (137)Cs accumulation in bivalves has important implications for biomonitoring and implementing management techniques. This study represents one of the first attempts to combine both dissolved and dietary pathways to give a realistic simulation of (137)Cs accumulation in marine bivalves under dynamic exposure regimes.

  10. Effect of potential-dependent potassium uptake on calcium accumulation in rat brain mitochondria.

    PubMed

    Akopova, O V; Kolchinskaya, L I; Nosar, V I; Bouryi, V A; Mankovskaya, I N; Sagach, V F

    2013-01-01

    The effect of potential-dependent potassium uptake at 0-120 mM K+ on matrix Ca2+ accumulation in rat brain mitochondria was studied. An increase in oxygen consumption and proton extrusion rates as well as increase in matrix pH with increase in K+ content in the medium was observed due to K+ uptake into the mitochondria. The accumulation of Ca2+ was shown to depend on K+ concentration in the medium. At K+ concentration ≤30 mM, Ca2+ uptake is decreased due to K+-induced membrane depolarization, whereas at higher K+ concentrations, up to 120 mM K+, Ca2+ uptake is increased in spite of membrane depolarization caused by matrix alkalization due to K+ uptake. Mitochondrial K+(ATP)-channel blockers (glibenclamide and 5-hydroxydecanoic acid) diminish K+ uptake as well as K+-induced depolarization and matrix alkalization, which results in attenuation of the potassium-induced effects on matrix Ca2+ uptake, i.e. increase in Ca2+ uptake at low K+ content in the medium due to the smaller membrane depolarization and decrease in Ca2+ uptake at high potassium concentrations because of restricted rise in matrix pH. The results show the importance of potential-dependent potassium uptake, and especially the K+(ATP) channel, in the regulation of calcium accumulation in rat brain mitochondria.

  11. Effects of the Fungal Endophyte Acremonium coenophialum on Nitrogen Accumulation and Metabolism in Tall Fescue

    PubMed Central

    Lyons, Philip C.; Evans, John J.; Bacon, Charles W.

    1990-01-01

    Infection by the fungal endophyte Acremonium coenophialum affected the accumulation of inorganic and organic N in leaf blades and leaf sheaths of KY 31 tall fescue (Festuca arundinacea Schreb.) grown under greenhouse conditions. Total soluble amino acid concentrations were increased in either the blade or sheath of the leaf from infected plants. A number of amino acids were significantly increased in the sheath, but only asparagine increased in the blade. Infection resulted in higher sheath NH4+ concentrations, whereas NO3− concentrations decreased in both leaf parts. The effects on amino acid, NO3−, and NH4+ concentrations were dependent upon the level of N fertilization and were usually apparent only at the high rate (10 millimolar) of application. Administration of 14CO2 to the leaf blades increased the accumulation of 14C in their amino acid fraction but not in the sheaths of infected plants. This may indicate that infection increased amino acid synthesis in the blade but that translocation to the sheath, which is the site of fungal colonization, was not affected. Glutamine synthetase activity was greater in leaf blades of infected plants at high and low N rates of fertilization, but nitrate reductase activity was not affected in either part of the leaf. Increased activities of glutamine synthetase together with the other observed changes in N accumulation and metabolism in endophyte-infected tall fescue suggest that NH4+ reassimilation could also be affected in the leaf blade. PMID:16667341

  12. Accumulation and distribution of trace metals within soils and the austral cordgrass Spartina densiflora in a Patagonian salt marsh.

    PubMed

    Idaszkin, Yanina L; Lancelotti, Julio L; Bouza, Pablo J; Marcovecchio, Jorge E

    2015-12-15

    Concentrations of Cd, Cu, Fe, Pb, and Zn were determined in soils and in below- and above-ground structures of Spartina densiflora in a Patagonian salt marsh (San Antonio, Río Negro, Argentina). Also, the relationship between trace metal concentrations in soils and plants was investigated to improve our knowledge regarding the ability of this plant species to take up and accumulate trace metals from the soil. Our results indicate that, within the studied salt marsh, soil trace metal concentrations follow a decreasing concentration gradient toward the sea. They show moderate pollution and a potentially negative biological effect in one site of the salt marsh. While below-ground structures reflect the soil metal concentration pattern, this is not so evident in above-ground concentrations. Also, S. densiflora is able to absorb a limited amount of metals present in the soil, the soil bioaccumulation factor being lower in sites where soil metal concentration is higher.

  13. Accumulation and distribution of trace metals within soils and the austral cordgrass Spartina densiflora in a Patagonian salt marsh.

    PubMed

    Idaszkin, Yanina L; Lancelotti, Julio L; Bouza, Pablo J; Marcovecchio, Jorge E

    2015-12-15

    Concentrations of Cd, Cu, Fe, Pb, and Zn were determined in soils and in below- and above-ground structures of Spartina densiflora in a Patagonian salt marsh (San Antonio, Río Negro, Argentina). Also, the relationship between trace metal concentrations in soils and plants was investigated to improve our knowledge regarding the ability of this plant species to take up and accumulate trace metals from the soil. Our results indicate that, within the studied salt marsh, soil trace metal concentrations follow a decreasing concentration gradient toward the sea. They show moderate pollution and a potentially negative biological effect in one site of the salt marsh. While below-ground structures reflect the soil metal concentration pattern, this is not so evident in above-ground concentrations. Also, S. densiflora is able to absorb a limited amount of metals present in the soil, the soil bioaccumulation factor being lower in sites where soil metal concentration is higher. PMID:26481413

  14. Accumulation of Trace Metal Elements (Cu, Zn, Cd, and Pb) in Surface Sediment via Decomposed Seagrass Leaves: A Mesocosm Experiment Using Zostera marina L.

    PubMed Central

    Konuma, Susumu; Nakamura, Yoshiyuki

    2016-01-01

    Accumulation of Cu, Zn, Cd, and Pb in the sediment of seagrass ecosystems was examined using mesocosm experiments containing Zostera marina (eelgrass) and reference pools. Lead was approximately 20-fold higher in the surface sediment in the eelgrass pool than in eelgrass leaves and epiphytes on the eelgrass leaves, whereas zinc and cadmium were significantly lower in the surface sediment than in the leaves, with intermediate concentrations in epiphytes. Copper concentrations were similar in both the surface sediment and leaves but significantly lower in epiphytes. Carbon and nitrogen contents increased significantly with increasing δ13C in surface sediments of both the eelgrass and reference pools. Copper, Zn, Cd, and Pb also increased significantly with increasing δ13C in the surface sediment in the eelgrass pool but not in the reference pool. By decomposition of eelgrass leaves with epiphytes, which was examined in the eelgrass pool, copper and lead concentrations increased more than 2-fold and approximately a 10-fold, whereas zinc and cadmium concentrations decreased. The high copper and lead concentrations in the surface sediment result from accumulation in decomposed, shed leaves, whereas zinc and cadmium remobilized from decomposed shed leaves but may remain at higher concentrations in the leaves than in the original sediments. The results of our mesocosm study demonstrate that whether the accumulation or remobilization of trace metals during the decomposition of seagrass leaves is trace metal dependent, and that the decomposed seagrass leaves can cause copper and lead accumulation in sediments in seagrass ecosystems. PMID:27336306

  15. Accumulation of Trace Metal Elements (Cu, Zn, Cd, and Pb) in Surface Sediment via Decomposed Seagrass Leaves: A Mesocosm Experiment Using Zostera marina L.

    PubMed

    Hosokawa, Shinya; Konuma, Susumu; Nakamura, Yoshiyuki

    2016-01-01

    Accumulation of Cu, Zn, Cd, and Pb in the sediment of seagrass ecosystems was examined using mesocosm experiments containing Zostera marina (eelgrass) and reference pools. Lead was approximately 20-fold higher in the surface sediment in the eelgrass pool than in eelgrass leaves and epiphytes on the eelgrass leaves, whereas zinc and cadmium were significantly lower in the surface sediment than in the leaves, with intermediate concentrations in epiphytes. Copper concentrations were similar in both the surface sediment and leaves but significantly lower in epiphytes. Carbon and nitrogen contents increased significantly with increasing δ13C in surface sediments of both the eelgrass and reference pools. Copper, Zn, Cd, and Pb also increased significantly with increasing δ13C in the surface sediment in the eelgrass pool but not in the reference pool. By decomposition of eelgrass leaves with epiphytes, which was examined in the eelgrass pool, copper and lead concentrations increased more than 2-fold and approximately a 10-fold, whereas zinc and cadmium concentrations decreased. The high copper and lead concentrations in the surface sediment result from accumulation in decomposed, shed leaves, whereas zinc and cadmium remobilized from decomposed shed leaves but may remain at higher concentrations in the leaves than in the original sediments. The results of our mesocosm study demonstrate that whether the accumulation or remobilization of trace metals during the decomposition of seagrass leaves is trace metal dependent, and that the decomposed seagrass leaves can cause copper and lead accumulation in sediments in seagrass ecosystems.

  16. Trace element accumulation in the moss Hypnum cupressiforme Hedw. and the trees Quercus ilex L. and Pinus halepensis Mill. in Catalonia.

    PubMed

    Sardans, Jordi; Peñuelas, Josep

    2005-09-01

    We studied trace element accumulation in the moss Hypnum cupressiforme and the widely distributed Mediterranean trees Quercus ilex and Pinus halepensis located at increasing distances from the Barcelona Metropolitan Area. Hypnum cupressiforme, Quercus ilex and, to a somewhat lesser extent, Pinus halepensis, have proved to be adequate as possible accumulative monitoring species in relation to trace elements pollution. No significant effects of crown orientation were found. One-year old leaves generally accumulated more trace elements than current-year leaves. All the studied trace elements showed greatest concentrations in the Barcelona Metropolitan Area, with lead, cadmium and arsenic concentrations being especially high. In general, trace element concentrations in biomass were similar or higher than the values reported from other Mediterranean urban areas of Europe. The top soil-layer concentrations were also higher in the Barcelona Metropolitan Area indicating the existence of mechanisms of atmospheric deposition and/or concentration in the soil. The lower values of Pb of airborne origin relative to other elements such as Cd, Cu, Zn and Sb suggest that traffic exhausts are not the only important focus of pollutants in this area. The results of biomass concentrations and of enrichment factor of biomasses respect to bedrock and soils show that atmospheric inputs account for the higher trace element concentrations in the Barcelona Metropolitan Area.

  17. The investigation of heavy element accumulation in some Hydrophilidae (Coleoptera) species.

    PubMed

    Aydoğan, Zeynep; Gürol, Ali; İncekara, Ümit

    2016-04-01

    First of all, this study aimed to find out the measures of some heavy elements (Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Sr, Pb) as heavy element pollution in Erzurum Province, and secondly to observe whether some hydrophilidae (Coleoptera) species can be used as a biomonitor. Insect samples were collected from five different localities of Erzurum in June, July, and August 2014. Heavy element levels in sediment, water, and insect samples were analyzed by energy-dispersive X-ray fluorescence (EDXRF) spectrometer device. According to the results of analysis derived through EDXRF spectrometry, heavy element concentrations display differences between stations and also species. The results pointed out that the insects were contaminated by the sediment and water; therefore, some hydrophilidae species accumulate higher concentration of elements than their environment. Results for levels in water were compared to national water quality guidelines. The values of some heavy elements found at higher concentration than acceptable limits. PMID:26935735

  18. Genetic analyses of anthocyanin concentrations and the intensity of red color in onion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Higher concentrations of anthocyanins in vegetables are important for attractive appearance and may offer health benefits for consumers. The red color of onion bulbs is due primarily to the accumulation of anthocyanins. Segregating haploid plants from the cross of yellow and red inbreds were asexual...

  19. Acetate limitation and nitrite accumulation during denitrification

    SciTech Connect

    Oh, J.; Silverstein, J.

    1999-03-01

    Nitrite accumulated in denitrifying activated sludge mixed liquor when the carbon and electron source, acetate, was limited. If acetate was added to obtain a carbon-to-nitrogen (C:N) ratio in the range of 2:1 to 3:1, nitrate was completely consumed at the same rate with no nitrite accumulation, indicating that nitrate concentration controlled the respiration rate as long as sufficient substrate was present. However, when acetate was reduced to a C:N ratio of 1:1, while nitrate continued to be consumed, > 50% of the initial nitrate-nitrogen accumulated as nitrite and 29% persisted as nitrite throughout an endogenous denitrification period of 8--9 h. While nitrite accumulated during acetate-limited denitrification, the specific nitrate reduction rate increased significantly compared with the rate when excess acetate was provided as follows: 0.034 mg-NO{sub 3}-N/mg-mixed liquid volatile suspended solids/h versus 0.023 mg-NO{sub 3}-N/mg-mixed liquid volatile suspended solids/h, respective. This may be explained by nitrate respiration out-competing nitrite respiration for limited acetate electrons. Complete restoration of balanced denitrification and elimination of nitrite accumulation during denitrification required several weeks after the C:N ratio was increased back to 2:1.

  20. Uptake, removal, accumulation, and phytotoxicity of phenol in willow trees (Salix viminalis).

    PubMed

    Ucisik, Ahmed Suheyl; Trapp, Stefan

    2006-09-01

    Phenol is an intermediate in the metabolism of plants, but it also is a high-volume production compound frequently found in the environment. The relation between removal, uptake, accumulation, and toxicity of phenol in willow trees (Salix viminalis) was determined. Willows were exposed to phenol levels up to 1000 mg/L in hydroponic solution and sand, respectively. The change on water transpiration of the trees was used to determine toxic effects. In both hydroponic solution and sand, only small inhibition of transpiration was detected up to phenol concentrations of 250 mg/L. For concentrations of 500 mg/L or greater, transpiration fell to 50% or less, and the trees wilted. The trees exposed to 1000 mg/L wilted and eventually died. For initial nominal concentrations of 1000 mg/L, a significantly higher amount of phenol remained at the end of the experiment compared to the amount remaining with all other concentrations. Phenol loss was approximately 90% for the trees that survived, except for trees exposed to the lowest concentration (10 mg/L). The loss of phenol was only 15 to 18% in experiments performed without trees. The results demonstrate a clear relation between removal, accumulation, and toxic effects of phenol in trees. Phenol levels of less than 250 mg/L could be degraded by "in planta" metabolism; therefore, no significant buildup of phenol nor any toxic effects in plants occurred. With higher levels, phenol was still degraded quickly, but an accumulation in trees accompanied by severe toxic effects occurred. Phytoremediation of phenol would be best with concentrations in water or soil solution of less than 250 mg/L, at which the degradation of phenol by willows or associated bacteria is rapid and efficient and the toxic effects on trees are negligible.

  1. Acclimation of two tomato species to high atmospheric CO sub 2 : I. Sugar and starch concentrations

    SciTech Connect

    Yelle, S.; Beeson, R.C. Jr.; Trudel, M.J.; Gosselin, A. )

    1989-08-01

    Lycopersicon esculentum Mill. cv Vedettos and Lycopersicon chmielewskii Rick, LA1028, were exposed to two CO{sub 2} concentrations for 10 weeks. Tomato plants grown at 900 microliters per liter contained more starch and more sugars than the control. However, we found no significant accumulation of starch and sugars in the young leaves of L. esculentum exposed to high CO{sub 2}. Carbon exchange rates were significantly higher in CO{sub 2}-enriched plants for the first few weeks of treatment but thereafter decreased as tomato plants acclimated to high atmospheric CO{sub 2}. This indicates that the long-term decline of photosynthetic efficiency of leaf 5 cannot be attributed to an accumulation of sugar and/or starch. The average concentration of starch in leaves 5 and 9 was always higher in L. esculentum than in L. chmielewskii (151.7% higher). A higher proportion of photosynthates was directed into starch for L. esculentum than for L. chmielewskii. However, these characteristics did not improve the long-term photosynthetic efficiency of L. chmielewskii grown at high CO{sub 2} when compared with L. esculentum. The chloroplasts of tomato plants exposed to the higher CO{sub 2} concentration exhibited a marked accumulation of starch. The results reported here suggest that starch and/or sugar accumulation under high CO{sub 2} cannot entirely explain the loss of photosynthetic efficiency of high CO{sub 2}-grown plants.

  2. Interaction between sulfur and lead in toxicity, iron plaque formation and lead accumulation in rice plant.

    PubMed

    Yang, Junxing; Liu, Zhiyan; Wan, Xiaoming; Zheng, Guodi; Yang, Jun; Zhang, Hanzhi; Guo, Lin; Wang, Xuedong; Zhou, Xiaoyong; Guo, Qingjun; Xu, Ruixiang; Zhou, Guangdong; Peters, Marc; Zhu, Guangxu; Wei, Rongfei; Tian, Liyan; Han, Xiaokun

    2016-06-01

    Human activities have resulted in lead and sulfur accumulation in paddy soils in parts of southern China. A combined soil-sand pot experiment was conducted to investigate the influence of S supply on iron plaque formation and Pb accumulation in rice (Oryza sativa L.) under two Pb levels (0 and 600 mg kg(-1)), combined with four S concentrations (0, 30, 60, and 120 mg kg(-1)). Results showed that S supply significantly decreased Pb accumulation in straw and grains of rice. This result may be attributed to the enhancement of Fe plaque formation, decrease of Pb availability in soil, and increase of reduced glutathione (GSH) in rice leaves. Moderate S supply (30 mg kg(-1)) significantly increased Fe plaque formation on the root surface and in the rhizosphere, whereas excessive S supply (60 and 120 mg kg(-1)) significantly decreased the amounts of iron plaque on the root surface. Sulfur supply significantly enhanced the GSH contents in leaves of rice plants under Pb treatment. With excessive S application, the rice root acted as a more effective barrier to Pb accumulation compared with iron plaque. Excessive S supply may result in a higher monosulfide toxicity and decreased iron plaque formation on the root surface during flooded conditions. However, excessive S supply could effectively decrease Pb availability in soils and reduce Pb accumulation in rice plants. PMID:26946285

  3. The Effects of the Capital Accumulation Ratio on Wealth

    ERIC Educational Resources Information Center

    Harness, Nathaniel J.; Finke, Michael S.; Chatterjee, Swarn

    2009-01-01

    The capital accumulation ratio (CAR) is commonly used in academic research as a measure of household portfolio quality. This study tested whether a higher initial CAR impacts change in wealth over a decade among households in the accumulation life cycle stage. Meeting the 25% CAR guideline resulted in a 28.1% increase in net worth between 1994 and…

  4. Differential accumulation of heavy metals by web spiders and ground spiders in an old-field

    SciTech Connect

    Larsen, K.J.; Brewer, S.R.; Taylor, D.H. . Dept. of Zoology)

    1994-03-01

    Accumulation of the heavy metals Cd, Cu, Pb, and Zn by web spiders (orb weavers: Araneidae) and ground spiders was examined in an old-field that had been subjected to 11 years of nutrient enrichment. The study area consistent of six 0.1-ha plots treated from 1978 to 1988 with municipal sewage sludge containing heavy-metal contaminants, urea-phosphate fertilizer, or left as untreated controls. In 1991 and 1992, heavy-metal concentrations in the soil, ground spiders, and web spiders were measured with a flame AA spectrophotometer. Spiders accumulated Cd, Cu, and Zn to concentrations greater than those present in the soil but did not accumulate Pb. Ground spiders contained significantly higher levels of Cd and Cu than web spiders, whereas web spiders contained slightly greater levels of Pb than ground spiders. No trend between spider guilds was apparent for Zn accumulation. To understand the impact of the application of metal-contaminated municipal sludge on ecosystem, the toxicological effects on the biology and behavior of major biotic components in terrestrial food webs must be known.

  5. Leaf gas exchange and solute accumulation in the halophyte Salvadora persica grown at moderate salinity.

    PubMed

    Maggio; Reddy; Joly

    2000-08-01

    The domestication of halophytes has been proposed as a strategy to expand cultivation onto unfavorable land. However, halophytes mainly have been considered for their performance in extremely saline environments, and only a few species have been characterized in terms of their tolerance and physiological responses to moderately high levels of salinity. Salvadora persica is an evergreen perennial halophyte capable of growing under extreme conditions, from very dry environments to highly saline soils. It possesses high potential economic value as a source of oil and medicinal compounds. To quantify its response to salinity, S. persica seedlings were exposed to 200 mM NaCl for 3 weeks, and growth, leaf gas exchange and solute accumulation were measured. The presence of NaCl induced a 100% increase in fresh weight and a 30% increase in dry weight, relative to non-salinized controls. Increases in fresh weight and dry weight were not associated with higher rates of net CO(2) assimilation, however. Analysis of ion accumulation revealed that S. persica leaves accumulated Na(+) as a primary osmoticum. The concentration of Na(+) in leaves of salinized plants was approximately 40-fold greater than that measured in non-salinized controls, and this was associated with significant reductions in leaf K(+) and Ca(2+) concentrations. In addition, a significant accumulation of proline, probably associated with osmotic adjustment and protection of membrane stability, occurred in roots of salinized plants.

  6. Choline metabolism in glycinebetaine accumulating and non-accumulating near-isogenic lines of Zea mays and Sorghum bicolor.

    PubMed

    Peel, Gregory J; Mickelbart, Michael V; Rhodes, David

    2010-03-01

    Glycinebetaine (GB) is a compatible solute that is accumulated by some plant species, especially under conditions leading to tissue osmotic stress. Genetic modification for accumulation of GB in an attempt to produce more stress tolerant plants has been a focus for several groups in recent years. However, attempts to increase tissue GB concentrations have been unsuccessful, with many transgenic lines accumulating far lower concentrations than naturally-occurring GB accumulators. A better understanding of the metabolic regulation of GB synthesis is necessary for successful molecular breeding and biotechnology. We utilized previously developed near-isogenic lines for GB accumulation to characterize the biochemical basis for GB deficiency in maize and sorghum. Salinity resulted in increased accumulation of choline in both accumulating and non-accumulating lines. When grown in the presence of NaCl, GB-non-accumulating lines had increased concentrations of choline and phosphocholine, but not GB. Decreased GB synthesis can be explained from the increased concentrations of phosphocholine in planta and the strong inhibition of N-phosphoethanolamine methyltransferase by phosphocholine observed in vitro. The lack of GB accumulation in GB-/- homozygous NILs was not due to the lack of the putative choline monooxygenase (the enzyme responsible for choline oxidation to betaine aldehyde) gene or protein that we describe. The previously identified bet1 locus does not appear to be choline monooxygenase. However, the lack of GB synthesis does affect the synthesis and turnover of choline moieties in GB non-accumulating lines, which may lead to alterations in overall 1-carbon metabolism in plants.

  7. Effects of water management on arsenic and cadmium speciation and accumulation in an upland rice cultivar.

    PubMed

    Hu, Pengjie; Ouyang, Younan; Wu, Longhua; Shen, Libo; Luo, Yongming; Christie, Peter

    2015-01-01

    Pot and field experiments were conducted to investigate the effects of water regimes on the speciation and accumulation of arsenic (As) and cadmium (Cd) in Brazilian upland rice growing in soils polluted with both As and Cd. In the pot experiment constant and intermittent flooding treatments gave 3-16 times higher As concentrations in soil solution than did aerobic conditions but Cd showed the opposite trend. Compared to arsenate, there were more marked changes in the arsenite concentrations in the soil solution as water management shifted, and therefore arsenite concentrations dominated the As speciation and bioavailability in the soil. In the field experiment As concentrations in the rice grains increased from 0.14 to 0.21 mg/kg while Cd concentrations decreased from 0.21 to 0.02 mg/kg with increasing irrigation ranging from aerobic to constantly flooding conditions. Among the various water regimes the conventional irrigation treatment produced the highest rice grain yield of 6.29 tons/ha. The As speciation analysis reveals that the accumulation of dimethylarsinic acid (from 11.3% to 61.7%) made a greater contribution to the increase in total As in brown rice in the intermittent and constant flooding treatments compared to the intermittent-aerobic treatment. Thus, water management exerted opposite effects on Cd and As speciation and bioavailability in the soil and consequently on their accumulation in the upland rice. Special care is required when irrigation regime methods are employed to mitigate the accumulation of metal(loid)s in the grain of rice grown in soils polluted with both As and Cd. PMID:25597681

  8. Pollutant accumulation patterns in nestlings of an avian top predator: biochemical and metabolic effects.

    PubMed

    Ortiz-Santaliestra, Manuel E; Resano-Mayor, Jaime; Hernández-Matías, Antonio; Rodríguez-Estival, Jaime; Camarero, Pablo R; Moleón, Marcos; Real, Joan; Mateo, Rafael

    2015-12-15

    The exposure to persistent pollutants such as organochlorine compounds (OCs) or metals has been associated with declines in top predator populations, which can accumulate high amounts of these pollutants from their prey. However, understanding how variation in OC and metal accumulation in wild species affects their biochemical and physiological responses is a big challenge, especially for endangered predators like the Bonelli's eagle (Aquila fasciata). This bird of prey is an interesting study model because the differences in diet composition among populations and territories can account for important pollutant uptake variations. We compared OC and metal accumulation in blood of Bonelli's eagle nestlings from three populations across Spain as a function of origin, age class (nestlings vs. adults), sex and number of siblings per nest, and related accumulation patterns to responses indicative of body condition, biochemistry and antioxidant status. Nestlings from Catalonia, the most industrialized area, showed the highest concentrations of PCBs and arsenic, and the lowest concentrations of zinc. The two former substances, together with DDTs, exerted an overall influence on nestling's physiology. PCBs and arsenic were associated with reduced retinol levels, pointing to oxidative damage in exposed individuals, which was also consistent with the low zinc levels in individuals from the polluted region. Increased plasma DDT levels were related to reduced body condition and lower levels of triglycerides. Mercury accumulation in Castile and Leon was higher in nestlings that were alone in the nest than in nestlings that shared it with a sibling; this suggests an increased mercury uptake from secondary prey in territories where preferred prey (i.e. rabbits) are scarce, which are also the territories where productivity is reduced. Overall, the results reveal a spatial variation in pollutant accumulation patterns and associated physiological effects, and suggest the major role

  9. Making sense of nickel accumulation and sub-lethal toxic effects in saline waters: Fate and effects of nickel in the green crab, Carcinus maenas.

    PubMed

    Blewett, Tamzin A; Glover, Chris N; Fehsenfeld, Sandra; Lawrence, Michael J; Niyogi, Som; Goss, Greg G; Wood, Chris M

    2015-07-01

    In freshwater, invertebrates nickel (Ni) is considered an ionoregulatory toxicant, but its mechanism of toxicity in marine settings, and how this varies with salinity, is poorly understood. This study investigated Ni accumulation and physiological mechanisms of sub-lethal Ni toxicity in the euryhaline green crab Carcinus maenas. Male crabs were exposed to 8.2μg/L (the US EPA chronic criterion concentration for salt waters) of waterborne Ni (radiolabelled with (63)Ni) at three different salinities, 20%, 60% and 100% SW for 24h. Whole body Ni accumulation in 20% SW was 3-5 fold greater than in 60% or 100% SW, and >80% of accumulated Ni was in the carapace at all salinities. Ni also accumulated in posterior gill 8, which showed a higher accumulation in 20% SW than in other salinities, a pattern also seen at higher exposure concentrations of Ni (500 and 3000μg/L). Gill perfusion experiments revealed that Ni was taken up by both anterior and posterior gills, but in 20% SW the posterior gill 8, which performs ionoregulatory functions, accumulated more Ni than the anterior gill 5, which primarily has a respiratory function. The sub-lethal consequences of Ni exposure were investigated by placing crabs in Ni concentrations of 8.2, 500, and 3000μg/L at 20, 60 or 100% SW for 24h. In 20% SW, haemolymph Ca levels were significantly decreased by exposure to Ni concentrations of 8.2μg/L or higher, whereas Na concentrations were depressed only at 3000μg/L. Na(+)/K(+)-ATPase activity was inhibited at both 500 and 3000μg/L in gill 8, but only in 20% SW. Haemolymph K, Mg, and osmolality were unaffected throughout, though all varied with salinity in the expected fashion. These data suggest that Ni impacts ionoregulatory function in the green crab, in a gill- and salinity-dependent manner. PMID:25914092

  10. Effect of different arbuscular mycorrhizal fungal isolates on growth and arsenic accumulation in Plantago lanceolata L.

    PubMed

    Orłowska, Elżbieta; Godzik, Barbara; Turnau, Katarzyna

    2012-09-01

    The role of indigenous and non-indigenous arbuscular mycorrhizal fungi (AMF) on As uptake by Plantago lanceolata L. growing on substrate originating from mine waste rich in As was assessed in a pot experiment. P. lanceolata inoculated with AMF had higher shoot and root biomass and lower concentrations of As in roots than the non-inoculated plants. There were significant differences in As concentration and uptake between different AMF isolates. Inoculation with the indigenous isolate resulted in increased transfer of As from roots to shoots; AMF from non-polluted area apparently restricted plants from absorbing As to the tissue; and plants inoculated with an AMF isolate from Zn-Pb waste showed strong As retainment within the roots. Staining with dithizone indicated that AMF might be actively involved in As accumulation. The mycorrhizal colonization affected also the concentration of Cd and Zn in roots and Pb concentration, both in shoots and roots. PMID:22609863

  11. Accumulation and regulation of zinc in Daphnia magna: links with homeostasis and toxicity.

    PubMed

    Muyssen, B T A; Janssen, C R

    2002-11-01

    Zinc accumulation in Daphnia magna was investigated, and the results were linked to the previously established optimal concentration range for zinc and D. magna. It was observed that organisms cultured in this optimal range (300-600 microg Zn/L) contained 212 +/- 57 to 254 +/- 79 microg Zn/g dry weight. Lower and higher zinc contents were obtained after acclimation to previously established culture concentrations inducing deficiency and toxicity, respectively. The calculation of bioconcentration factors indicated that zinc was actively regulated, at least up to a concentration of 600 microg Zn/L. Zinc uptake and elimination are rapid processes; major increases and decreases in body content occurred within 1 day. Zinc concentrations in daphnids exposed to 600 microg Zn/L fluctuated with 2- to 3-day intervals, suggesting a role of molting in the regulation and elimination of zinc. PMID:12399922

  12. Phosphorus accumulation and eutrophication in feed-supply freshwater fishponds.

    PubMed

    Zhang, Ming-kui; Fang, Li-ping

    2006-01-01

    The rapid growth and intensification of freshwater fishery can cause imbalances between phosphorus (P) input in feed and its output in produce. This aquaculture can result in enriching exogenous P in fishponds and, consequently, accelerates the process of eutrophication. To assess relations among input, accumulation, release of P and as a consequence degrading water quality in terms of chlorophyll-a (Chl-a) in freshwater fishponds, fourteen fishponds with feed supply, nine fishponds without feed supply, and five non-fish ponds in Shaoxing Plain, southeast China were selected for comparing P accumulation in their waters and surface sediments. Surface sediment samples were collected from each pond to evaluate their total P, water soluble P, Olsen P, algal available P, and P fractions. Water samples were also collected from the ponds to measure concentrations of dissolved P and Chl-a. Total P in the sediments ranged from 0.88 to 1.73 g/kg in the fishponds with feed supply, that in the non-fish ponds ranged from 0.47 to 0.86 g/kg. Organic P, accounted for 23% to 60% of total P in the sediments, was an important P fraction and increased linearly with increasing organic matter. Long-term application of feeds resulted in increased P availability in the bottom sediments and degradation of water quality in the freshwater fishponds. Compared with non-fish ponds, sediments from the feed-supplied fishponds contained considerably higher Olsen P, algal available P, and water soluble P. Higher proportions of the labile P (NH4Cl-P) and potentially labile P (NaOH-IP) were also found in the sediments from the fishponds. High solubility of P in the sediments resulted in elevation of P and chlorophyll-a concentration in the pond water. The dissolved P concentration in the pond water increased in the order of non-fish ponds (12 microg/L) < fishponds without feed supply (24 microg/L) < fishponds with feed supply (66 microg/L). Linear correlations between concentrations of total P, Olsen

  13. Effect of continuous ozone injection on performance and biomass accumulation of biofilters treating gaseous toluene.

    PubMed

    Xi, Jinying; Saingam, Prakit; Gu, Feng; Hu, Hong-Ying; Zhao, Xuefei

    2014-11-01

    Biofilters treating high-concentration gaseous volatile organic compounds (VOC) can be subject to bed clogging induced by excess biomass accumulation. In this study, O3 was continuously injected into biofilters to control biomass. Its effects on the performance of the biofilters and on biomass accumulation were investigated. Four identical biofilters designed to treat gaseous toluene were operated for 70 days, and three of them were continuously injected with O3 at different concentrations (from 80 to 320 mg/m(3)). The results showed that continuous O3 injection could effectively keep the bed pressure drop stable and had no adverse effect on toluene removal when O3 concentrations were 180-220 mg/m(3). The maximum toluene elimination capacity of the four biofilters was 140 g-toluene/m(3)/h, and the bed pressure drop of the biofilter fed with 180-220 mg/m(3) O3 remained below 3 mmH2O/m throughout the operation period. The biomass accumulation rates of the three biofilters with O3 at 80-320 mg/m(3) were lowered by 0.15-0.25 g/L/day compared with the biofilter without O3. The decreases in biomass accumulation resulted in higher void fractions of the filter beds with O3 injection. Carbon balance analysis indicated that CO2 production had increased while biomass accumulation and leachate waste production decreased in response to O3 injection. Based on the experimental results, it was concluded here that continuous O3 injection can reduce increases in bed pressure effectively, preserve VOC removal capacity, and prevent production of extra leachate waste.

  14. Effect of continuous ozone injection on performance and biomass accumulation of biofilters treating gaseous toluene.

    PubMed

    Xi, Jinying; Saingam, Prakit; Gu, Feng; Hu, Hong-Ying; Zhao, Xuefei

    2015-01-01

    Biofilters treating high-concentration gaseous volatile organic compounds (VOC) can be subject to bed clogging induced by excess biomass accumulation. In this study, O3 was continuously injected into biofilters to control biomass. Its effects on the performance of the biofilters and on biomass accumulation were investigated. Four identical biofilters designed to treat gaseous toluene were operated for 70 days, and three of them were continuously injected with O3 at different concentrations (from 80 to 320 mg/m(3)). The results showed that continuous O3 injection could effectively keep the bed pressure drop stable and had no adverse effect on toluene removal when O3 concentrations were 180-220 mg/m(3). The maximum toluene elimination capacity of the four biofilters was 140 g-toluene/m(3)/h, and the bed pressure drop of the biofilter fed with 180-220 mg/m(3) O3 remained below 3 mmH2O/m throughout the operation period. The biomass accumulation rates of the three biofilters with O3 at 80-320 mg/m(3) were lowered by 0.15-0.25 g/L/day compared with the biofilter without O3. The decreases in biomass accumulation resulted in higher void fractions of the filter beds with O3 injection. Carbon balance analysis indicated that CO2 production had increased while biomass accumulation and leachate waste production decreased in response to O3 injection. Based on the experimental results, it was concluded here that continuous O3 injection can reduce increases in bed pressure effectively, preserve VOC removal capacity, and prevent production of extra leachate waste.

  15. Spatial and interspecific variation of accumulated trace metals between remote and urbane dwelling birds of Pakistan.

    PubMed

    Abbasi, Naeem Akhtar; Khan, Muhammad Usman; Jaspers, Veerle Leontina Bernard; Chaudhry, Muhammad Jamshed Iqbal; Malik, Riffat Naseem

    2015-03-01

    The current study was designed to evaluate the hypothesis that birds of urbanized and/or industrialized origin depict higher metal accumulation as compared to remote dwellers. We selected seven representative species from three families (Anatidae, Motacillidae and Sturnidae) at two different locations; Baroghil valley (remote location) and Soan valley (urbanized location) of Pakistan and analyzed the concentrations of 8 metals Pb, Cd, Cr, Ni, Cu, Mn, Fe and Zn in feathers of these species. Feathers from Soan valley which is under higher anthropogenic influence exhibited significantly (P<0.001) higher metal concentrations when compared with the feathers of the same species at Baroghil valley which has negligible anthropogenic input. Terrestrial birds of the Baroghil valley revealed greater metal loads than aquatic birds while at Soan valley it was vice versa. In general, elevated concentrations of metals were recorded in insectivorous species as compared to omnivorous species. Within each location, species belonging to Anatidae and Motacillidae revealed similar metal contamination patterns. Principal component Analysis (PCA) based on correlation matrices depicted a clear tendency of metals towards the species originating from areas with greater pollution load (Soan valley) than relatively undisturbed sites (Baroghil valley) and hence corroborated our hypothesis. The pattern of metal accumulation in feathers of both the locations suggested that there may be a flux of migration between the two regions and/or trans-boundary movement of pollutants/metals, which either singly or synergistically influence the overall metal profile in the studied bird species.

  16. Evaluation of chitooligosaccharide application on mineral accumulation and plant growth in Phaseolus vulgaris.

    PubMed

    Chatelain, Philippe G; Pintado, Manuela E; Vasconcelos, Marta W

    2014-02-01

    Chitooligosaccharides (COS) - water soluble derivatives from chitin, are an interesting group of molecules for several biological applications, for they can enter plant cells and bind negatively charged molecules. Several studies reported an enhanced plant growth and higher crop yield due to chitosan application in soil grown plants, but no studies have looked on the effect of COS application on plant mineral nutrient dynamics in hydroponically grown plants. In this study, Phaseolus vulgaris was grown in hydroponic culture and the effect of three different concentrations of COS on plant growth and mineral accumulation was assessed. There were significant changes in mineral allocations for Mo, B, Zn, P, Pb, Cd, Mn, Fe, Mg, Ca, Cu, Na, Al and K among treatments. Plant morphology was severely affected in high doses of COS, as well as lignin concentration in the stem and the leaves, but not in the roots. Chlorophyll A, B and carotenoid concentrations did not change significantly among treatments, suggesting that even at higher concentrations, COS application did not affect photosynthetic pigment accumulation. Plants grown at high COS levels had shorter shoots and roots, suggesting that COS can be phytotoxic to the plant. The present study is the first detailed report on the effect of COS application on mineral nutrition in plants, and opens the door for future studies that aim at utilizing COS in biofortification or phytoremediation programs.

  17. Evaluation of chitooligosaccharide application on mineral accumulation and plant growth in Phaseolus vulgaris.

    PubMed

    Chatelain, Philippe G; Pintado, Manuela E; Vasconcelos, Marta W

    2014-02-01

    Chitooligosaccharides (COS) - water soluble derivatives from chitin, are an interesting group of molecules for several biological applications, for they can enter plant cells and bind negatively charged molecules. Several studies reported an enhanced plant growth and higher crop yield due to chitosan application in soil grown plants, but no studies have looked on the effect of COS application on plant mineral nutrient dynamics in hydroponically grown plants. In this study, Phaseolus vulgaris was grown in hydroponic culture and the effect of three different concentrations of COS on plant growth and mineral accumulation was assessed. There were significant changes in mineral allocations for Mo, B, Zn, P, Pb, Cd, Mn, Fe, Mg, Ca, Cu, Na, Al and K among treatments. Plant morphology was severely affected in high doses of COS, as well as lignin concentration in the stem and the leaves, but not in the roots. Chlorophyll A, B and carotenoid concentrations did not change significantly among treatments, suggesting that even at higher concentrations, COS application did not affect photosynthetic pigment accumulation. Plants grown at high COS levels had shorter shoots and roots, suggesting that COS can be phytotoxic to the plant. The present study is the first detailed report on the effect of COS application on mineral nutrition in plants, and opens the door for future studies that aim at utilizing COS in biofortification or phytoremediation programs. PMID:24388524

  18. Role of taurine accumulation in keratinocyte hydration.

    PubMed

    Janeke, Guido; Siefken, Wilfried; Carstensen, Stefanie; Springmann, Gunja; Bleck, Oliver; Steinhart, Hans; Höger, Peter; Wittern, Klaus-Peter; Wenck, Horst; Stäb, Franz; Sauermann, Gerhard; Schreiner, Volker; Doering, Thomas

    2003-08-01

    Epidermal keratinocytes are exposed to a low water concentration at the stratum corneum-stratum granulosum interface. When epithelial tissues are osmotically perturbed, cellular protection and cell volume regulation is mediated by accumulation of organic osmolytes such as taurine. Previous studies reported the presence of taurine in the epidermis of several animal species. Therefore, we analyzed human skin for the presence of the taurine transporter (TAUT) and studied the accumulation of taurine as one potential mechanism protecting epidermal keratinocytes from dehydration. According to our results, TAUT is expressed as a 69 kDa protein in human epidermis but not in the dermis. For the epidermis a gradient was evident with maximal levels of TAUT in the outermost granular keratinocyte layer and lower levels in the stratum spinosum. No TAUT was found in the basal layer or in the stratum corneum. Keratinocyte accumulation of taurine was induced by experimental induction of skin dryness via application of silica gel to human skin. Cultured human keratinocytes accumulated taurine in a concentration- and osmolarity-dependent manner. TAUT mRNA levels were increased after exposure of human keratinocytes to hyperosmotic culture medium, indicating osmosensitive TAUT mRNA expression as part of the adaptation of keratinocytes to hyperosmotic stress. Keratinocyte uptake of taurine was inhibited by beta-alanine but not by other osmolytes such as betaine, inositol, or sorbitol. Accumulation of taurine protected cultured human keratinocytes from both osmotically induced and ultraviolet-induced apoptosis. Our data indicate that taurine is an important epidermal osmolyte required to maintain keratinocyte hydration in a dry environment. PMID:12880428

  19. Uptake and accumulation of phosphorus by dominant plant species growing in a phosphorus mining area.

    PubMed

    Xiao, Guangli; Li, Tingxuan; Zhang, Xizhou; Yu, Haiying; Huang, Huagang; Gupta, D K

    2009-11-15

    Phosphorus accumulation potentials were investigated for 12 dominant plant species growing in a phosphorus mining area in Shifang, as well as their corresponding non-mining ecotypes growing in Ya'an, China. High phosphorus concentrations were observed in the seedling and flowering stages of two species, Pilea sinofasciata and Polygonum hydropiper, up to 16.23 and 8.59 g kg(-1), respectively, which were 3.4 and 7 times higher than in the non-mining ecotypes. Available phosphorus levels in the respective rhizosphere soils of these plants were 112.84 and 121.78 mg kg(-1), 12 and 4 times higher than in the non-rhizosphere soil. Phosphorus concentrations in shoots of the mining ecotypes of all 12 species were significantly negatively correlated with available phosphorus in the rhizosphere soils (p<0.05), whereas a positive correlation was observed in the non-mining ecotypes. The biomass in shoot of the mining ecotype of P. hydropiper was nearly 2 times that in the non-mining ecotype. The results suggested that P. sinofasciata and P. hydropiper were efficient candidates among the tested species for phosphorus accumulation in shoots, and that further studies should be conducted to investigate their potential to be adopted as phosphorus accumulators.

  20. Variation in organotin accumulation in relation to the life history in the Japanese eel Anguilla japonica

    NASA Astrophysics Data System (ADS)

    Ohji, Madoka; Harino, Hiroya; Arai, Takaomi

    2009-08-01

    In order to examine the ecological risks caused by organotin compounds (OTs) in diadromous fish migrating between sea and freshwaters, tributyltin (TBT) and triphenyltin (TPT) compounds and their breakdown products were determined in the catadromous eel Anguilla japonica, which has sea, estuarine and river life histories, collected in Japanese sea, brackish and freshwaters within the same region. Ontogenic changes in otolith strontium (Sr) and calcium (Ca) concentrations were examined along the life history transect to discriminate the migration type. There were generally three different patterns, which were categorized as 'sea eels', 'estuarine eels' and 'river eels' according to the otolith Sr:Ca ratio. The concentrations of TBT in silver eels (mature eels) were significantly higher than that in yellow eels (immature eels), and the percentages of TBT were also higher in silver eels than in yellow eels. A positive correlation was found between TBT concentration and the gonad-somatic index (GSI). It is thus considered that silver eels have a higher risk of contamination by TBT than yellow eels. TBT and TPT concentrations in sea eels were significantly higher than those in river eels, while no significant differences were observed in TBT and TPT concentrations in estuarine eels compared to sea and river eels. These results suggest that sea eels have a higher ecological risk of OT contamination than river eels during their life history, and the risk of OTs in estuarine eels is considered to be intermediate between that of sea and river eels. Positive linear relationships were found between Sr:Ca ratios and the concentrations of TBT and TPT. Therefore, these results suggest that the ecological risk of OTs increase as the sea residence period in the eel becomes longer. TBT and TPT concentrations in sea eels were significantly higher than those in river eels even at the same growth stage. Thus, it is clear that migratory type is the most important factor for OT

  1. Proline accumulation and metabolism-related genes expression profiles in Kosteletzkya virginica seedlings under salt stress

    PubMed Central

    Wang, Hongyan; Tang, Xiaoli; Wang, Honglei; Shao, Hong-Bo

    2015-01-01

    Proline accumulation is a common response to salt stress in many plants. Salt stress also increased proline concentration in roots, stems, and leaves of Kosteletzkya virginica seedling treated with 300 mM NaCl for 24 h and reached 3.75-, 4.76-, and 6.83-fold higher than controls. Further study on proline content in leaves under salt stress showed that proline content increased with increasing NaCl concentrations or time. The proline level peaked at 300 mM NaCl for 24 h and reached more than sixfold higher than control, but at 400 mM NaCl for 24 h proline content fell back slightly along with wilting symptom. To explore the cause behind proline accumulation, we first cloned full length genes related to proline metabolism including KvP5CS1, KvOAT, KvPDH, and KvProT from K. virginica and investigated their expression profiles. The results revealed that the expressions of KvP5CS1 and KvProT were sharply up-regulated by salt stress and the expression of KvOAT showed a slight increase with increasing salt concentrations or time, while the expression of KvPDH was not changed much and slightly decreased before 12 h and then returned to the original level. As the key enzyme genes for proline biosynthesis, the up-regulated expression of KvP5CS1 played a more important role than KvOAT for proline accumulation in leaves under salt stress. The low expression of KvPDH for proline catabolism also made a contribution to proline accumulation before 12 h. PMID:26483809

  2. Enhanced arsenic accumulation by engineered yeast cells expressing Arabidopsis thaliana phytochelatin synthase.

    PubMed

    Singh, Shailendra; Lee, Wonkyu; Dasilva, Nancy A; Mulchandani, Ashok; Chen, Wilfred

    2008-02-01

    Phytochelatins (PCs) are naturally occurring peptides with high-binding capabilities for a wide range of heavy metals including arsenic (As). PCs are enzymatically synthesized by phytochelatin synthases and contain a (gamma-Glu-Cys)(n) moiety terminated by a Gly residue that makes them relatively proteolysis resistant. In this study, PCs were introduced by expressing Arabidopsis thaliana Phytochelatin Synthase (AtPCS) in the yeast Saccharomyces cerevisiae for enhanced As accumulation and removal. PCs production in yeast resulted in six times higher As accumulation as compared to the control strain under a wide range of As concentrations. For the high-arsenic concentration, PCs production led to a substantial decrease in levels of PC precursors such as glutathione (GSH) and gamma-glutamyl cysteine (gamma-EC). The levels of As(III) accumulation were found to be similar between AtPCS-expressing wild type strain and AtPCS-expressing acr3Delta strain lacking the arsenic efflux system, suggesting that the arsenic uptake may become limiting. This is further supported by the roughly 1:3 stoichiometric ratio between arsenic and PC2 (n = 2) level (comparing with a theoretical value of 1:2), indicating an excess availability of PCs inside the cells. However, at lower As(III) concentration, PC production became limiting and an additive effect on arsenic accumulation was observed for strain lacking the efflux system. More importantly, even resting cells expressing AtPCS pre-cultured in Zn(2+) enriched media showed PCs production and two times higher arsenic removal than the control strain. These results open up the possibility of using cells expressing AtPCS as an inexpensive sorbent for the removal of toxic arsenic.

  3. Sublethal effects of contamination on the Mediterranean sponge Crambe crambe: metal accumulation and biological responses.

    PubMed

    Cebrian, E; Martí, R; Uriz, J M; Turon, X

    2003-10-01

    The effect of low levels of pollution on the growth, reproduction output, morphology and survival of adult sponges and settlers of the sponge Crambe crambe were examined. We transplanted sponges from a control area to a contaminated site and measured the main environmental variables (chemical and physical) of both sites during the study period. Except some punctual differences in particulate organic matter, silicates, nitrates, and water motion, most environmental variables in the water were similar at both sites during the study months. Mainly copper, lead and OM concentrations in the sediment, and water motion were significantly higher at the polluted site and may be implicated in the biological effects observed: decrease in the percentage of specimens with embryos, increase in shape irregularity and decrease in growth rate. Individuals naturally occurring at the polluted site and those transplanted there for four months accumulated ten times more copper than either untouched or transplant controls. Although lead concentration in sediment did not differ between sites, native specimens from the contaminated site accumulated this metal more than untouched controls. Vanadium concentration also tended to increase in the sponges living at or transplanted to the contaminated site but this difference was not significant. C. crambe is a reliable indicator of metal contamination since it accumulates copper, lead and vanadium in high amounts. At the contaminated site, sponge growth, fecundity and survival were inhibited, whereas sponge irregularity ending in sponge fission was promoted. All these effects may compromise the structure and dynamics of the sponge populations in sheltered, metal-contaminated habitats.

  4. Accumulation of storage products in oat during kernel development.

    PubMed

    Banaś, A; Dahlqvist, A; Debski, H; Gummeson, P O; Stymne, S

    2000-12-01

    Lipids, proteins and starch are the main storage products in oat seeds. As a first step in elucidating the regulatory mechanisms behind the deposition of these compounds, two different oat varieties, 'Freja' and 'Matilda', were analysed during kernel development. In both cultivars, the majority of the lipids accumulated at very early stage of development but Matilda accumulated about twice the amount of lipids compared to Freja. Accumulation of proteins and starch started also in the early stage of kernel development but, in contrast to lipids, continued over a considerably longer period. The high-oil variety Matilda also accumulated higher amounts of proteins than Freja. The starch content in Freja kernels was higher than in Matilda kernels and the difference was most pronounced during the early stage of development when oil synthesis was most active. Oleosin accumulation continued during the whole period of kernel development.

  5. Phytoremediation of heavy-metal-polluted soils: screening for new accumulator plants in Angouran mine (Iran) and evaluation of removal ability.

    PubMed

    Chehregani, Abdolkarim; Noori, Mitra; Yazdi, Hossein Lari

    2009-07-01

    Heavy metal pollution is a worldwide problem. Phytoremediation is an effective and low-cost interesting technology. This study was conducted in a dried waste pool of a lead and zinc mine in Angouran (Iran) to find accumulator plant(s). Concentrations of heavy metals were determined both in the soil and the plants that were grown in the mine and out of mine. The concentration of total Cu, Fe, Zn, Pb and Ni in the mine area were higher than the control soil. The results showed that five dominant vegetations namely Amaranthus retroflexus, Polygonum aviculare, Gundelia tournefortii, Noea mucronata and Scariola orientalis accumulated heavy metals. Based on the results, it was concluded that N. mucronata is the best accumulator for Pb, Zn, Cu, Cd and Ni, but the best Fe accumulator is A. retroflexus. Phytoremediation ability of N. mucronata was evaluated in experimental pots. The study showed that the amounts of heavy metals were decreased in polluted soils during experiments. The accumulation of metals in the root, leave and shoot portions of N. mucronata varied significantly but all the concentrations were more than natural soils. The results indicated that N. mucronata is an effective accumulator plant for phytoremediation of heavy-metals-polluted soils.

  6. Nitrogen accumulation in forests. Exposure monitoring by mosses.

    PubMed

    Pesch, Roland; Schröder, Winfried; Schmidt, Gunther

    2007-03-21

    At present, there is still little information on nitrogen (N) accumulation in forests contrasting with the crucial importance of N in forest ecosystems. This work analyzes the N bioaccumulation in mosses from forested areas from Lower Saxony and North Rhine-Westphalia (two of 16 federal states of Germany), the Weser Ems Region (part of Lower Saxony), and the Euro Region Nissa (covering the Czech Republic, Germany, Poland). The studies involved samples collected from 190 sites between 1998 and 2005. Different spatial scales and regional differences in land use were chosen to assess the factors affecting N bioaccumulation in forested areas. A continuous reduction of N bioaccumulation was found from Lower Saxony (a region where agriculture is most predominant) to North Rhine-Westphalia (mostly urban). The Weser Ems Region (an agricultural region) showed a higher N concentration in mosses than the Euroregion Nissa (a former industrial region). Statistical analyses performed at the different spatial scales revealed that the areas showing greater agricultural and livestock spatial densities favor N bioaccumulation in mosses. N concentration in mosses was moderately correlated with the N concentration in the leaves and needles of the surrounding trees. No significant relationships were found regarding the crown density of forest trees or N deposition estimations from a combination of atmospheric models and deposition measurements.

  7. Accumulation of dieldrin in an alga (Scenedesmus obliquus), Daphnia magna, and the guppy (Poecilia reticulata)

    USGS Publications Warehouse

    Reinert, Robert E.

    1972-01-01

    Scenedesmus obliquus, Daphnia magna, and Poecilia reticulata accumulated dieldrin directly from water; average concentration factors (concentration in organism, dry weight, divided by concentration in water) were 1282 for the alga, 13,954 for D. magna, and 49,307 (estimated) for the guppy. The amount accumulated by each species at equilibrium (after about 1.5, 3-4, and 18 days, respectively) was directly proportional to the concentration of dieldrin in the water. Daphnia magna and guppies accumulated more dieldrin from water than from food that had been exposed to similar concentrations in water. When guppies were fed equal daily rations of D. magna containing different concentrations of insecticide, the amounts of dieldrin accumulated by the fish were directly proportional to the concentration in D. magna; when two lots of guppies were fed different quantities of D. magna (10 and 20 organisms per day) containing identical concentrations of dieldrin, however, the amounts accumulated did not differ substantially.

  8. Relation of Nickel Concentrations in Tree Rings to Groundwater Contamination

    NASA Astrophysics Data System (ADS)

    Yanosky, Thomas M.; Vroblesky, Don A.

    1992-08-01

    Increment cores were collected from trees growing at two sites where groundwater is contaminated by nickel. Proton-induced X ray emission spectroscopy was used to determine the nickel concentrations in selected individual rings and in parts of individual rings. Ring nickel concentrations were interpreted on the basis of recent concentrations of nickel in aquifers, historical information about site use activities, and model simulations of groundwater flow. Nickel concentrations in rings increased during years of site use but not in trees outside the contaminated aquifers. Consequently, it was concluded that trees may preserve in their rings an annual record of nickel contamination in groundwater. Tulip trees and oaks contained higher concentrations of nickel than did sassafras, sweet gum, or black cherry. No evidence was found that nickel accumulates consistently within parts of individual rings or that nickel is translocated across ring boundaries.

  9. Phytochelatin concentrations in the equatorial Pacific

    NASA Astrophysics Data System (ADS)

    Ahner, Beth A.; Lee, Jennifer G.; Price, Neil M.; Morel, François M. M.

    1998-11-01

    Phytochelatin, an intracellular metal-binding polypeptide synthesized in eucaryotic algae in response to metals such as Cd and Cu, was measured in particulate samples collected from the equatorial Pacific. The concentrations in these samples (normalized to total particulate chl a) were unexpectedly high compared to laboratory culture data and were on average slightly more than in coastal areas where the metal concentrations are typically much greater. In part, the high field concentrations can be explained by the low cellular concentrations of chlorophyll a resulting from very low ambient Fe, but laboratory experiments provide a possible explanation for the rest of the difference. At low concentrations of inorganic Cd (Cd'=3 pM), increasing amounts of phytochelatin were induced by decreasing Zn concentrations in the culture medium of two diatoms: Thalassiosira weissflogii, a coastal species, and T. parthenaia, an isolate from the equatorial Pacific. In all previous studies, phytochelatin production has been directly correlated with increasing metal concentrations. Decreasing Co also resulted in higher phytochelatin concentrations in T. weissflogii and Emiliania huxleyi. Replicating the field concentrations of Zn, Co, and Cd in the laboratory results in cellular concentrations (amol -1 cell) that are very similar to those estimated for the field. Contrary to the expectation that high metal concentrations in the equatorial upwelling would cause elevated phytochelatin concentrations, there was no increase in phytochelatin concentrations from 20° S to 10° N—near surface samples were roughly the same at all stations. Also, most of the depth profiles had a distinct subsurface maximum. Neither of these features is readily explained by the available Zn and Cd data. Incubations with additions of Cd and Cu performed on water sampled at four separate stations induced significantly higher concentrations of phytochelatins than those in controls in a majority of the samples

  10. Seasonal variations of number size distributions and mass concentrations of atmospheric particles in Beijing

    NASA Astrophysics Data System (ADS)

    Yu, Jianhua; Guinot, Benjamin; Yu, Tong; Wang, Xin; Liu, Wenqing

    2005-06-01

    Particle number and mass concentrations were measured in Beijing during the winter and summer periods in 2003, together with some other parameters including black carbon (BC) and meteorological conditions. Particle mass concentrations exhibited low seasonality, and the ratio of PM2.5/PM10 in winter was higher than that in summer. Particle number size distribution (PSD) was characterized by four modes and exhibited low seasonality. BC was well correlated with the number and mass concentrations of accumulation and coarse particles, indicating these size particles are related to anthropogenic activities. Particle mass and number concentrations (except ultra-fine and nucleation particles) followed well the trends of BC concentration for the majority of the day, indicating that most particles were associated with primary emissions. The diurnal number distributions of accumulation and coarse mode particles were characterized by two peaks.

  11. Accumulation of furanocoumarins by Bituminaria bituminosa in relation to plant development and environmental stress.

    PubMed

    Walker, David J; Martínez-Fernández, Domingo; Correal, Enrique; Romero-Espinar, Pascual; Antonio Del Río, José

    2012-05-01

    Bituminaria bituminosa (L.) C.H. Stirton (Fabaceae) accumulates high concentrations of the furanocoumarins (FCs) angelicin and psoralen, which protect against infection and herbivory. The effects on FC accumulation of the exposure of two populations of B. bituminosa to abiotic stress (cold, heat and drought) under field conditions were determined, as well as the effect of temperature under controlled conditions, in hydroponic culture. In field conditions, psoralen and angelicin levels in the leaf dry matter were 400-6000 and 1500-11,000 μg g(-), respectively. There were significant effects of population on the psoralen concentration and psoralen:angelicin ratio. In hydroponic culture, exposure to a diurnal temperature of 33 °C increased FC levels in population Calnegre but not in Llano del Beal, compared with plants grown at 22 °C; however, high summer temperatures in the field (>30 °C) did not coincide with the highest leaf FC levels, since the plants accumulated FCs preferentially in the fruits. Hence, leaf FC levels were higher in winter. Irrigation, to alleviate water stress in the semi-arid conditions, increased the fruit psoralen concentration but produced only minor decreases in leaf FC levels. There was a significant, positive correlation (P < 0.001) between the FC and nitrogen concentrations in the plant organs analysed (both increased in the order: fruits > growing leaves > mature leaves), reflecting their respective contributions to plant fitness. The genetically- and developmentally-regulated accumulation of FCs by B. bituminosa is altered by short-term variations in environmental conditions, particularly temperature.

  12. Accumulation of chlorinated benzenes in earthworms

    USGS Publications Warehouse

    Beyer, W.N.

    1996-01-01

    Chlorinated benzenes are widespread in the environment. Hexachlorobenzene, pentachlorobenzene and all isomers of dichlorobenzenes, trichlorobenzenes, and tetrachlorobenzenes, have been detected in fish, water, and sediments from the Great Lakes. This paper describes a long-term (26 week) experiment relating the concentrations of chlorinated benzenes in earthworms to 1) the length of exposure, and it describes three 8-week experiments relating concentrations of chlorinated benzenes in earthworms to 2) their concentration in soil 3) the soil organic matter content and, 4) the degree of chlorination. In the 26-week experiment, the concentration of 1,2,4 - trichlorobenzene in earthworms fluctuated only slightly about a mean of 0.63 ppm (Fig. 1). Although a statistically significant decrease can be demonstrated over the test (Pearson correlation coefficient, r = -0.62 p < 0.05), the decrease was minor. Hexachlorobenzene in earthworms showed a cyclical trend that coincided with replacement of the media, and a slight but statistically significant tendency to increase from about 2 to 3 ppm over the 26 weeks (r = 0.55, p < 0.05). Concentrations of both trichlorobenzene and hexachlorobenzene in earthworms increased as the concentrations in the soil increased (Fig. 2), but leveled off at the highest soil concentrations. The most surprising result of this study was the relatively low concentrations in earthworms compared to those in soils. The average concentration of each of the six isomers of trichlorobenzene and tetrachlorobenzene in earthworms was only about 1 ppm (Table 2); the isomeric structure did not affect accumulation. The concentration of organic matter in soil had a prominent effect on hexachlorobenzene concentrations in earthworms (Fig. 3). Hexachlorobenzene concentrations decreased steadily from 9.3 ppm in earthworms kept in soil without any peat moss added to about 1 ppm in soil containing 16 or 32% organic matter.

  13. Nitrogen Accumulation, Transformations, And Export In Urban Ecosystems

    NASA Astrophysics Data System (ADS)

    Zhu, W.

    2006-05-01

    Global N biogeochemical cycle, like the global C cycle, has been fundamentally altered by human activities. Unlike C cycling, N inputs are regionally concentrated in human-dominated ecosystems such as large cities. The fate of elevated N input has important ecological and environmental consequences. In the arid Southwest, large quantities of N inputs can be accumulated in soils, due to the primary constraints of water on N usages and transfers. In a probability-based field sampling conducted in year 2000 in Central Arizona-Phoenix (a 6400- km2 study area), we found that farming and urbanization on average had caused an accumulative storage of 72.3 kg N/ha, mostly in the form of nitrate, in the surface 30 cm of soils. Hydrologic flowpaths over the arid urban landscapes could affect the fate of N. Our measured denitrification in urban retention basins had rates that were comparable to the highest reported in literature and constituted an important mechanism for N removal. In mesic Northeast, elevated atmospheric N deposition could alleviate natural N limitation to the ecosystem. Studies in remnant forests along an urban-to-rural gradient in the New York City metropolitan area showed higher soil N mineralization in urban sites than in rural sites. N transformations were found shifting from soluble organic N and NH4+ dominance to NO3- and nitrification, in agreement with the N saturation hypothesis. Changes in N biogeochemistry, however, are likely due to the combination of exotic earthworm invasion and the increase of N input, with both closely tied to human activities. Increases in ecosystem N availability and the shifting of N biogeochemical pathways lead to elevated N export. Using a small watershed approach, we studied Upper Susquehanna River drainage basin, the headwater area of the Chesapeake Bay. Our results showed significantly higher nitrate concentrations in urban streams than those watersheds with considerable agricultural land-use and rural watersheds

  14. Ontogenetic dynamics of mercury accumulation in Northwest Atlantic sea lamprey (Petromyzon marinus)

    USGS Publications Warehouse

    Drevnick, P.E.; Horgan, M.J.; Oris, J.T.; Kynard, B.E.

    2006-01-01

    We examined the ontogenetic dynamics of mercury accumulation in sea lamprey (Petromyzon marinus) from the Connecticut River, USA. Mercury concentrations in eggs (mean 84 ng??g-1 wet weight) were lowest of all life stages and correlated to concentrations in females. There was a higher rate of maternal transfer of mercury to eggs compared with teleosts. Ammocoetes had high mercury concentrations for their trophic level (e.g., mean of age-4 ammocoetes 492 ng??g-1 wet weight). A further investigation of four streams showed that ammocoetes reflected the level of contamination in their nursery streams. Concentrations of mercury decreased during metamorphosis from ammocoete to adult. Mercury concentrations in adults ranged from 83 to 942 ng??g-1 wet weight and, unlike teleosts, showed no relation to sex, length, or weight. We provide evidence from stable isotope analyses that this high variability is due to feeding ecology. There are fundamental differences in mercury accumulation between sea lamprey and teleosts. ?? 2006 NRC Canada.

  15. Plasma Hypoxanthine-Guanine Phosphoribosyl Transferase Activity in Bottlenose Dolphins Contributes to Avoiding Accumulation of Non-recyclable Purines

    PubMed Central

    López-Cruz, Roberto I.; Crocker, Daniel E.; Gaxiola-Robles, Ramón; Bernal, Jaime A.; Real-Valle, Roberto A.; Lugo-Lugo, Orlando; Zenteno-Savín, Tania

    2016-01-01

    Marine mammals are exposed to ischemia/reperfusion and hypoxia/reoxygenation during diving. During oxygen deprivation, adenosine triphosphate (ATP) breakdown implies purine metabolite accumulation, which in humans is associated with pathological conditions. Purine recycling in seals increases in response to prolonged fasting and ischemia. Concentrations of metabolites and activities of key enzymes in purine metabolism were examined in plasma and red blood cells from bottlenose dolphins (Tursiops truncatus) and humans. Hypoxanthine and inosine monophosphate concentrations were higher in plasma from dolphins than humans. Plasma hypoxanthine-guanine phosphoribosyl transferase (HGPRT) activity in dolphins suggests an elevated purine recycling rate, and a mechanism for avoiding accumulation of non-recyclable purines (xanthine and uric acid). Red blood cell concentrations of hypoxanthine, adenosine diphosphate, ATP and guanosine triphosphate were lower in dolphins than in humans; adenosine monophosphate and nicotinamide adenine dinucleotide concentrations were higher in dolphins. HGPRT activity in red blood cells was higher in humans than in dolphins. The lower concentrations of purine catabolism and recycling by-products in plasma from dolphins could be beneficial in providing substrates for recovery of ATP depleted during diving or vigorous swimming. These results suggest that purine salvage in dolphins could be a mechanism for delivering nucleotide precursors to tissues with high ATP and guanosine triphosphate requirements. PMID:27375492

  16. Plasma Hypoxanthine-Guanine Phosphoribosyl Transferase Activity in Bottlenose Dolphins Contributes to Avoiding Accumulation of Non-recyclable Purines.

    PubMed

    López-Cruz, Roberto I; Crocker, Daniel E; Gaxiola-Robles, Ramón; Bernal, Jaime A; Real-Valle, Roberto A; Lugo-Lugo, Orlando; Zenteno-Savín, Tania

    2016-01-01

    Marine mammals are exposed to ischemia/reperfusion and hypoxia/reoxygenation during diving. During oxygen deprivation, adenosine triphosphate (ATP) breakdown implies purine metabolite accumulation, which in humans is associated with pathological conditions. Purine recycling in seals increases in response to prolonged fasting and ischemia. Concentrations of metabolites and activities of key enzymes in purine metabolism were examined in plasma and red blood cells from bottlenose dolphins (Tursiops truncatus) and humans. Hypoxanthine and inosine monophosphate concentrations were higher in plasma from dolphins than humans. Plasma hypoxanthine-guanine phosphoribosyl transferase (HGPRT) activity in dolphins suggests an elevated purine recycling rate, and a mechanism for avoiding accumulation of non-recyclable purines (xanthine and uric acid). Red blood cell concentrations of hypoxanthine, adenosine diphosphate, ATP and guanosine triphosphate were lower in dolphins than in humans; adenosine monophosphate and nicotinamide adenine dinucleotide concentrations were higher in dolphins. HGPRT activity in red blood cells was higher in humans than in dolphins. The lower concentrations of purine catabolism and recycling by-products in plasma from dolphins could be beneficial in providing substrates for recovery of ATP depleted during diving or vigorous swimming. These results suggest that purine salvage in dolphins could be a mechanism for delivering nucleotide precursors to tissues with high ATP and guanosine triphosphate requirements.

  17. Plasma Hypoxanthine-Guanine Phosphoribosyl Transferase Activity in Bottlenose Dolphins Contributes to Avoiding Accumulation of Non-recyclable Purines.

    PubMed

    López-Cruz, Roberto I; Crocker, Daniel E; Gaxiola-Robles, Ramón; Bernal, Jaime A; Real-Valle, Roberto A; Lugo-Lugo, Orlando; Zenteno-Savín, Tania

    2016-01-01

    Marine mammals are exposed to ischemia/reperfusion and hypoxia/reoxygenation during diving. During oxygen deprivation, adenosine triphosphate (ATP) breakdown implies purine metabolite accumulation, which in humans is associated with pathological conditions. Purine recycling in seals increases in response to prolonged fasting and ischemia. Concentrations of metabolites and activities of key enzymes in purine metabolism were examined in plasma and red blood cells from bottlenose dolphins (Tursiops truncatus) and humans. Hypoxanthine and inosine monophosphate concentrations were higher in plasma from dolphins than humans. Plasma hypoxanthine-guanine phosphoribosyl transferase (HGPRT) activity in dolphins suggests an elevated purine recycling rate, and a mechanism for avoiding accumulation of non-recyclable purines (xanthine and uric acid). Red blood cell concentrations of hypoxanthine, adenosine diphosphate, ATP and guanosine triphosphate were lower in dolphins than in humans; adenosine monophosphate and nicotinamide adenine dinucleotide concentrations were higher in dolphins. HGPRT activity in red blood cells was higher in humans than in dolphins. The lower concentrations of purine catabolism and recycling by-products in plasma from dolphins could be beneficial in providing substrates for recovery of ATP depleted during diving or vigorous swimming. These results suggest that purine salvage in dolphins could be a mechanism for delivering nucleotide precursors to tissues with high ATP and guanosine triphosphate requirements. PMID:27375492

  18. Mercury accumulation of three Lactarius mushroom species.

    PubMed

    Falandysz, Jerzy

    2017-01-01

    Accumulation, distribution and potential dietary intake of mercury accumulated by mushrooms of Lactarius species L. delicious, L. volemus and L. deterrimus were studied in the Pomerania region of Poland. In total, 212 fruiting bodies and 106 underlying topsoil samples were analyzed. Analysis indicated that the concentrations of Hg were at low levels both in mushrooms and forest topsoils for a majority of the locations investigated. L. volemus that grew in soils with only a slightly elevated contamination (0.11±0.07mgkg(-1) of dried soil), very efficiently accumulated Hg in fruiting bodies and concentration levels were at 3.7±1.3mgkg(-1) of dry biomass in caps and at 1.9±0.9mgkg(-1) of dry biomass in stipes. Consumption of mushrooms foraged from the Sobowidz forest, which is close to a foundry using ferrous and non-ferrous metals could result in a Hg intake that exceeds the current statutory limits. PMID:27507453

  19. Noise Reduction by Signal Accumulation

    ERIC Educational Resources Information Center

    Kraftmakher, Yaakov

    2006-01-01

    The aim of this paper is to show how the noise reduction by signal accumulation can be accomplished with a data acquisition system. This topic can be used for student projects. In many cases, the noise reduction is an unavoidable part of experimentation. Several techniques are known for this purpose, and among them the signal accumulation is the…

  20. Trace-element accumulation by Hygrohypnum ochraceum in the upper Rio Grande Basin, Colorado and New Mexico, USA

    SciTech Connect

    Carter, L.F.; Porter, S.D.

    1997-12-01

    Accumulation of 12 trace elements by transplanted aquatic bryophytes (Hygrohypnum ochraceum) was determined at 13 sites in the Rio Grande and tributary streams in southern Colorado and northern New Mexico as part of the US Geological Survey`s National Water-Quality Assessment Program. The purposes of the study were to determine the spatial distribution of trace elements in relation to land-use practices in the upper Rio Grande Basin, compare accumulation rates of metals in bryophytes at sites contaminated by trace elements, and evaluate transplanted aquatic bryophytes as a tool for examining the bioavailability of trace elements in relation to concentrations in water and bed sediment. Concentrations of Cd, Cu, Pb, and Zn in bryophytes, water, and bed sediment were significantly higher at sites that receive drainage from mining areas than at sites near agricultural or urban activities. Concentrations of most trace elements were lower in a tributary stream below an urban source than at sites near mining or agricultural use. Concentrations of Cu and Zn in bryophytes correlated with concentrations in water and bed sediment. In addition, bryophyte concentrations of As, Cd, and Pb correlated with concentrations in bed sediment. Transplanted bryophytes can provide an indication of bioavailability. Rates of accumulation were related to the magnitude of ambient trace-element concentrations; maximal uptake occurred during the first 10 d of exposure. Trace-element concentrations in transplanted bryophytes could potentially be used to predict water and sediment concentrations that represent an integration of conditions over short to intermediate lengths of time, rather than instantaneous conditions as measured using water samples.

  1. Trace-element accumulation by Hygrohypnum ochraceum in the upper Rio Grande Basin, Colorado and New Mexico, Usa

    USGS Publications Warehouse

    Carter, L.F.; Porter, S.D.

    1997-01-01

    Accumulation of 12 trace elements by transplanted aquatic bryophytes (Hygrohypnum ochraceum) was determined at 13 sites in the Rio Grande and tributary streams in southern Colorado and northern New Mexico as part of the U.S. Geological Survey's National Water-Quality Assessment Program. The purposes of the study were to determine the spatial distribution of trace elements in relation to land-use practices in the upper Rio Grande Basin, compare accumulation rates of metals in bryophytes at sites contaminated by trace elements, and evaluate transplanted aquatic bryophytes as a tool for examining the bioavailability of trace elements in relation to concentrations in water and bed sediment. Concentrations of Cd, Cu, Pb, and Zn in bryophytes, water, and bed sediment were significantly higher at sites that receive drainage from mining areas than at sites near agricultural or urban activities. Concentrations of most trace elements were lower in a tributary stream below an urban source than at sites near mining or agricultural use. Concentrations of Cu and Zn in bryophytes correlated with concentrations in water and bed sediment. In addition, bryophyte concentrations of As, Cd, and Pb correlated with concentrations in bed sediment. Transplanted bryophytes can provide an indication of bioavailability. Rates of accumulation were related to the magnitude of ambient trace-element concentrations; maximal uptake occurred during the first 10 d of exposure. Trace-element concentrations in transplanted bryophytes could potentially be used to predict water and sediment concentrations that represent an integration of conditions over short to intermediate lengths of time, rather than instantaneous conditions as measured using water samples.

  2. Characteristics of nonylphenol and bisphenol A accumulation by fish and implications for ecological and human health.

    PubMed

    Lee, Ching-Chang; Jiang, Ling-Ying; Kuo, Yi-Ling; Chen, Chung-Yu; Hsieh, Chia-Yi; Hung, Chung-Feng; Tien, Chien-Jung

    2015-01-01

    Fish populations constitute an important part of aquatic ecosystems. Thus, their accumulation of nonylphenol (NP) and bisphenol A (BPA) may pose risks to ecosystems and human health. This study analyzed the concentrations of NP and BPA in four types of fishes (i.e., wild/farmed freshwater fishes and wild/farmed marine fishes). Wild freshwater fishes contained higher concentrations of NP and BPA than the other three types of fishes. The concentrations of NP in the wild freshwater fishes ranged from 1.01 to 277 μg/kg ww, with bioconcentration factors (BCFs) and biota-sediment accumulation factors (BSAFs) ranging from 74.0 to 2.60 × 10(4)L/kg and from 0.003 to 18.3, respectively. The wild freshwater fishes contained relatively low amounts of BPA, varying from ND to 25.2 μg/kg ww, with the BCFs and BSAFs ranging from 1.00 to 274L/kg and from 0.003 to 3.40, respectively. Five fish species particularly showed high BCFs and BSAFs, indicating that they could be an important source of NP for higher trophic levels, most likely resulting in ecological risks. The demersal fishes showed a greater ability to accumulate NP than the pelagic ones. The fact that the 95th percentile values of the risk quotient (RQ) for NP and BPA were higher than the acceptable threshold indicated that these two compounds would have adverse effects on aquatic organisms in Taiwanese rivers. The consumption of wild marine fishes had the highest 95th percentile values of hazard quotient (HQ) for NP and BPA among the four types of fishes, particularly for the population aged 0-3 years. However, the 95th percentile values of HQ for NP and BPA were all less than 1, suggesting that exposure to NP and BPA through fish consumption posed no remarkable risk to human health in Taiwan.

  3. Element accumulation, distribution, and phytoremediation potential in selected metallophytes growing in a contaminated area.

    PubMed

    Nadgórska-Socha, Aleksandra; Kandziora-Ciupa, Marta; Ciepał, Ryszard

    2015-07-01

    The distribution of elements in three pseudometallophytes species Cardaminopsis arenosa, Plantago lanceolata, and Plantago major, naturally occurring at metalliferous and non-metalliferous sites in southern Poland, was investigated. The accumulation of Al, Cd, Cu, Fe, Mn, Pb, Zn, as well as Ca, P, Na, and K in shoots and roots was measured. The level of the accumulated trace elements (ATE) was visibly higher in C. arenosa and P. lanceolata from metalliferous sites than non-contaminated ones. However, the level of the accumulated nutrient elements (ANE) was visibly higher only in C. arenosa plants. Also, higher potassium share in ANE was found in the shoots of C. arenosa and Plantago species from metalliferous sites than non-contaminated ones. The highest content of Cd, Zn, Pb, Al, Fe, and Mn was found in C. arenosa, which better reflected metal concentrations in the metalliferous and non-metalliferous soil than other plants. In the studied Plantago species, in almost all cases in all sites TF (translocation coefficient) and MR (mobility ratio) were below 1, which indicates they use the excluder strategy. The best accumulation ability was found for C. arenosa. The higher translocation coefficients (TF > 1) for Zn and Cd in C. arenosa shoots make it suitable for phytoextraction from soil, while the lower translocation ratios (TF < 1) for Zn and Cd in Plantago species and also for Pb in C. arenosa make them suitable for phytostabilization. Almost in all cases the plants had enrichment coefficient >2, which suggested that they may act as indicators of the soil metal contamination.

  4. Element accumulation, distribution, and phytoremediation potential in selected metallophytes growing in a contaminated area.

    PubMed

    Nadgórska-Socha, Aleksandra; Kandziora-Ciupa, Marta; Ciepał, Ryszard

    2015-07-01

    The distribution of elements in three pseudometallophytes species Cardaminopsis arenosa, Plantago lanceolata, and Plantago major, naturally occurring at metalliferous and non-metalliferous sites in southern Poland, was investigated. The accumulation of Al, Cd, Cu, Fe, Mn, Pb, Zn, as well as Ca, P, Na, and K in shoots and roots was measured. The level of the accumulated trace elements (ATE) was visibly higher in C. arenosa and P. lanceolata from metalliferous sites than non-contaminated ones. However, the level of the accumulated nutrient elements (ANE) was visibly higher only in C. arenosa plants. Also, higher potassium share in ANE was found in the shoots of C. arenosa and Plantago species from metalliferous sites than non-contaminated ones. The highest content of Cd, Zn, Pb, Al, Fe, and Mn was found in C. arenosa, which better reflected metal concentrations in the metalliferous and non-metalliferous soil than other plants. In the studied Plantago species, in almost all cases in all sites TF (translocation coefficient) and MR (mobility ratio) were below 1, which indicates they use the excluder strategy. The best accumulation ability was found for C. arenosa. The higher translocation coefficients (TF > 1) for Zn and Cd in C. arenosa shoots make it suitable for phytoextraction from soil, while the lower translocation ratios (TF < 1) for Zn and Cd in Plantago species and also for Pb in C. arenosa make them suitable for phytostabilization. Almost in all cases the plants had enrichment coefficient >2, which suggested that they may act as indicators of the soil metal contamination. PMID:26088758

  5. Influences of major nutrient elements on Pb accumulation of two crops from a Pb-contaminated soil.

    PubMed

    Lin, Changcun; Zhu, Tingcheng; Liu, Li; Wang, Deli

    2010-02-15

    To know about the effect of major nutrient elements on various forms of Pb and metal extraction, a greenhouse experiment was conducted to assess the effects of various major nutrient elements on Pb accumulation in two crops (Spinacia oleracea, SO and Sonchus arvensis, SA) in Changchun, China. Results indicated that, for SO, the Pb concentrations in both shoots and roots had no difference with increasing nutrients except for low nutrient treatment (1/2H). For SA, high nutrient treatments (2H and 3H) resulted in higher Pb concentrations in roots than low and standard nutrient treatments (1/2H and C), but high Pb concentration in shoot appeared in low and highest nutrient treatments (1/2H and 3H). The nitrogenous nutrient treatment (2N) had the most effect of increasing Pb concentrations in roots of SO and SA. The potassic and phosphorus nutrient treatments (2K and 2P) had little effect on the Pb concentrations in plant tissues for SO. Pb concentration in SO was lower than SA. Because of the higher total biomass in SO than SA, the ability to Pb accumulation in SO was better than SA. Sequential extraction results indicated that the addition of soil amendments transform soil Pb from bioavailable fractions to non-bioavailable fraction substantially. The results suggest that nitrogen fertilizer for SO and phosphorus fertilizer for SA are the most effective materials for the remediation of Pb-contaminated soils, and increase the tolerance of crops to Pb contamination.

  6. Interaction of Nickel and Manganese in Accumulation and Localization in Leaves of the Ni Hyperaccumulators Alyssum murale and Alyssum corsicum

    SciTech Connect

    Broadhurst, C.; Tappero, R; Maugel, T; Erbe, E; Sparks, D; Chaney, R

    2009-01-01

    The genus Alyssum contains >50 Ni hyperaccumulator species; many can achieve >2.5% Ni in dry leaf. In soils with normal Mn levels, Alyssum trichome bases were previously observed to accumulate Ni and Mn to high levels. Here we report concentration and localization patterns in A. murale and A. corsicum grown in soils with nonphytotoxic factorial additions of Ni and Mn salts. Four leaf type subsets based on size and age accumulated Ni and Mn similarly. The greatest Mn accumulation (10 times control) was observed in A. corsicum with 40 mmol Mn kg-1 and 40 mmol Ni kg-1 added to potting soil. Whole leaf Ni concentrations decreased as Mn increased. Synchrotron X-ray fluorescence mapping of whole fresh leaves showed localized in distinct high-concentration Mn spots associated with trichomes, Ni and Mn distributions were strongly spatially correlated. Standard X-ray fluorescence point analysis/mapping of cryofractured and freeze-dried samples found that Ni and Mn were co-located and strongly concentrated only in trichome bases and in cells adjacent to trichomes. Nickel concentration was also strongly spatially correlated with sulfur. Results indicate that maximum Ni phytoextraction by Alyssum may be reduced in soils with higher phytoavailable Mn, and suggest that Ni hyperaccumulation in Alyssum species may have developed from a Mn handling system.

  7. Elliptical concentrators.

    PubMed

    Garcia-Botella, Angel; Fernandez-Balbuena, Antonio Alvarez; Bernabeu, Eusebio

    2006-10-10

    Nonimaging optics is a field devoted to the design of optical components for applications such as solar concentration or illumination. In this field, many different techniques have been used to produce optical devices, including the use of reflective and refractive components or inverse engineering techniques. However, many of these optical components are based on translational symmetries, rotational symmetries, or free-form surfaces. We study a new family of nonimaging concentrators called elliptical concentrators. This new family of concentrators provides new capabilities and can have different configurations, either homofocal or nonhomofocal. Translational and rotational concentrators can be considered as particular cases of elliptical concentrators. PMID:17068595

  8. Naturally evolved enhanced Cd tolerance of Dianthus carthusianorum L. is not related to accumulation of thiol peptides and organic acids.

    PubMed

    Wójcik, Małgorzata; Dresler, Sławomir; Plak, Andrzej; Tukiendorf, Anna

    2015-05-01

    Two contrasting ecotypes of Dianthus carthusianorum L., metallicolous (M) and nonmetallicolous (NM), were cultivated in hydroponics at 0-50 μM Cd for 14 days to compare their Cd accumulation, sensitivity and tolerance mechanisms. While both ecotypes contained similar concentrations of Cd in the shoots and roots, the M ecotype was more Cd-tolerant (as measured by fresh weight production and root and leaf viability). Both ecotypes accumulated phytochelatins (PCs) in response to Cd with a higher amount thereof found in the NM ecotype. Concentrations of PCs remained unchanged with increasing Cd concentrations in the root tissues, but their content in the shoots increased. The addition of L-buthionine-sulfoximine (BSO) diminished glutathione (GSH) accumulation and arrested PC production, which increased the sensitivity to Cd of the NM, but not M ecotype. Organic acids (malate and citrate) as well as proline accumulation did not change significantly after Cd exposition and was at the same level in both ecotypes. The enhanced Cd tolerance of the M ecotype of D. carthusianorum cannot be explained in terms of restricted Cd uptake and differential production of PCs, organic acids or proline; some other mechanisms must be involved in its adaptation to the high Cd content in the environment. PMID:25510617

  9. Naturally evolved enhanced Cd tolerance of Dianthus carthusianorum L. is not related to accumulation of thiol peptides and organic acids.

    PubMed

    Wójcik, Małgorzata; Dresler, Sławomir; Plak, Andrzej; Tukiendorf, Anna

    2015-05-01

    Two contrasting ecotypes of Dianthus carthusianorum L., metallicolous (M) and nonmetallicolous (NM), were cultivated in hydroponics at 0-50 μM Cd for 14 days to compare their Cd accumulation, sensitivity and tolerance mechanisms. While both ecotypes contained similar concentrations of Cd in the shoots and roots, the M ecotype was more Cd-tolerant (as measured by fresh weight production and root and leaf viability). Both ecotypes accumulated phytochelatins (PCs) in response to Cd with a higher amount thereof found in the NM ecotype. Concentrations of PCs remained unchanged with increasing Cd concentrations in the root tissues, but their content in the shoots increased. The addition of L-buthionine-sulfoximine (BSO) diminished glutathione (GSH) accumulation and arrested PC production, which increased the sensitivity to Cd of the NM, but not M ecotype. Organic acids (malate and citrate) as well as proline accumulation did not change significantly after Cd exposition and was at the same level in both ecotypes. The enhanced Cd tolerance of the M ecotype of D. carthusianorum cannot be explained in terms of restricted Cd uptake and differential production of PCs, organic acids or proline; some other mechanisms must be involved in its adaptation to the high Cd content in the environment.

  10. Accumulations of heavy metals in roadside soils close to zhaling, eling and nam co lakes in the tibetan plateau.

    PubMed

    Yan, Xuedong; Zhang, Fan; Gao, Dan; Zeng, Chen; Xiang, Wang; Zhang, Man

    2013-06-07

    Concentrations of four typical heavy metals (Cu; Zn; Cd and Pb) in roadside soils close to three lakes in the Tibetan Plateau were investigated in this study. The hierarchical tree-based regression method was applied to classify concentrations of the heavy metals and analyze their potential influencing factors. It was found that the Tibetan Plateau meadow soils with higher content of sand lead to higher concentrations of Cu; Zn and Pb. The concentrations of Cd and Pb increase with road traffic volume; and for the road segments with higher traffic volume; the Cd and Pb concentrations significantly decrease with the roadside distance. Additionally; the concentrations of Zn and Pb increase as the altitude of sampling site increases. Furthermore; the Hakanson potential ecological risk index method was used to assess the contamination degree of the heavy metals for the study regions. The results show that accumulations of Cu; Zn and Pb in roadside soils remain an unpolluted level at all sites. However; the Cd indices in the regions with higher traffic volume have reached a strong potential ecological risk level; and some spots with peak concentrations have even been severely polluted due to traffic activities.

  11. Accumulations of Heavy Metals in Roadside Soils Close to Zhaling, Eling and Nam Co Lakes in the Tibetan Plateau

    PubMed Central

    Yan, Xuedong; Zhang, Fan; Gao, Dan; Zeng, Chen; Xiang, Wang; Zhang, Man

    2013-01-01

    Concentrations of four typical heavy metals (Cu; Zn; Cd and Pb) in roadside soils close to three lakes in the Tibetan Plateau were investigated in this study. The hierarchical tree-based regression method was applied to classify concentrations of the heavy metals and analyze their potential influencing factors. It was found that the Tibetan Plateau meadow soils with higher content of sand lead to higher concentrations of Cu; Zn and Pb. The concentrations of Cd and Pb increase with road traffic volume; and for the road segments with higher traffic volume; the Cd and Pb concentrations significantly decrease with the roadside distance. Additionally; the concentrations of Zn and Pb increase as the altitude of sampling site increases. Furthermore; the Hakanson potential ecological risk index method was used to assess the contamination degree of the heavy metals for the study regions. The results show that accumulations of Cu; Zn and Pb in roadside soils remain an unpolluted level at all sites. However; the Cd indices in the regions with higher traffic volume have reached a strong potential ecological risk level; and some spots with peak concentrations have even been severely polluted due to traffic activities. PMID:23749055

  12. Evidence of aluminium accumulation in aluminium welders.

    PubMed Central

    Elinder, C G; Ahrengart, L; Lidums, V; Pettersson, E; Sjögren, B

    1991-01-01

    Using atomic absorption spectrometry the aluminium concentrations in blood and urine and in two iliac bone biopsies obtained from welders with long term exposure to fumes containing aluminium were measured. The urinary excretion of two workers who had welded for 20 and 21 years varied between 107 and 351 micrograms Al/l, more than 10 times the concentration found in persons without occupational exposure. Urinary aluminium excretion remained high many years after stopping exposure. Blood and bone aluminium concentrations (4-53 micrograms Al/l and 18-29 micrograms Al/g respectively) were also raised but not to the same extent as urine excretion. It is concluded that long term exposure to aluminium by inhalation gives rise to accumulation of aluminium in the body and skeleton of health persons, and that the elimination of retained aluminium is very slow, in the order of several years. PMID:1954151

  13. Accumulation of current-use pesticides in neotropical montane forests.

    PubMed

    Daly, Gillian L; Lei, Ying D; Teixeira, Camilla; Muir, Derek C G; Castillo, Luisa E; Wania, Frank

    2007-02-15

    In Central America, chemical-intensive tropical agriculture takes place in close proximity to highly valued and biologically diverse ecosystems, yet the potential for atmospheric transport of pesticides from plantations to national parks and other reserves is poorly characterized. The specific meteorological conditions of mountain ranges can lead to contaminant convergence at high altitudes, raising particular concern for montane forest ecosystems downwind from pesticide use areas. Here we show, based on a wide-ranging air and soil sampling campaign across Costa Rica, that soils in some neotropical montane forests indeed display much higher concentrations of currently used pesticides than soils elsewhere in the country. Specifically, elevated concentrations of the fungicide chlorothalonil, the herbicide dacthal, and the insecticide metabolite endosulfan sulfate on volcanoes Barva and Poas, lying directly downwind of the extensive banana plantations of the Caribbean lowland, indicate the occurrence of atmospheric transport and wet deposition of pesticides at high altitudes. Calculations with a contaminant fate model, designed for mountain regions and parametrized to the Costa Rican environment, show that chemicals with a log K(AW) between -3 and -5 have a greater potential for accumulation at high altitudes. This enrichment behavior is quantified by the Mountain Contamination Potential and is sensitive to contaminant degradability. The modeling work supports the hypothesis suggested by the field results that it is enhanced precipitation scavenging at high elevations (caused by lower temperatures and governed by K(AW)) that causes pesticides to accumulate in tropical montane areas. By providing for the first time evidence of significant transfer of currently used pesticides to Central American montane cloud forests, this study highlights the need to evaluate the risk that tropical agricultural practices place on the region's ecological reserves.

  14. Accumulation of current-use pesticides in neotropical montane forests.

    PubMed

    Daly, Gillian L; Lei, Ying D; Teixeira, Camilla; Muir, Derek C G; Castillo, Luisa E; Wania, Frank

    2007-02-15

    In Central America, chemical-intensive tropical agriculture takes place in close proximity to highly valued and biologically diverse ecosystems, yet the potential for atmospheric transport of pesticides from plantations to national parks and other reserves is poorly characterized. The specific meteorological conditions of mountain ranges can lead to contaminant convergence at high altitudes, raising particular concern for montane forest ecosystems downwind from pesticide use areas. Here we show, based on a wide-ranging air and soil sampling campaign across Costa Rica, that soils in some neotropical montane forests indeed display much higher concentrations of currently used pesticides than soils elsewhere in the country. Specifically, elevated concentrations of the fungicide chlorothalonil, the herbicide dacthal, and the insecticide metabolite endosulfan sulfate on volcanoes Barva and Poas, lying directly downwind of the extensive banana plantations of the Caribbean lowland, indicate the occurrence of atmospheric transport and wet deposition of pesticides at high altitudes. Calculations with a contaminant fate model, designed for mountain regions and parametrized to the Costa Rican environment, show that chemicals with a log K(AW) between -3 and -5 have a greater potential for accumulation at high altitudes. This enrichment behavior is quantified by the Mountain Contamination Potential and is sensitive to contaminant degradability. The modeling work supports the hypothesis suggested by the field results that it is enhanced precipitation scavenging at high elevations (caused by lower temperatures and governed by K(AW)) that causes pesticides to accumulate in tropical montane areas. By providing for the first time evidence of significant transfer of currently used pesticides to Central American montane cloud forests, this study highlights the need to evaluate the risk that tropical agricultural practices place on the region's ecological reserves. PMID:17593708

  15. Cadmium tolerance and accumulation in cultivars of a high-biomass tropical tree (Averrhoa carambola) and its potential for phytoextraction.

    PubMed

    Li, J T; Liao, B; Lan, C Y; Ye, Z H; Baker, A J M; Shu, W S

    2010-01-01

    Averrhoa carambola is a high-biomass tropical tree that has been identified as a Cd accumulator. In the present study, field survey, pot, and hydroponic experiments were conducted to investigate the variation of Cd tolerance and accumulation in cultivars of A. carambola as well as its potential for phytoextraction. In the field survey, it was found that concentrations of Cd in aerial tissues of A. carambola varied greatly among sites and cultivars. The Cd bioconcentration factors (BCFs) and Cd removals by the field-grown A. carambola differed significantly among sites but not among cultivars. Nonetheless, all four carambola cultivars investigated were able to accumulate considerably high concentrations of Cd in their shoots, which indicated that the 4-yr-old carambola stands could remove 0.3 to 51.8% of the total Cd content in the top 20-cm soil layer. When cultured in Cd-spiked soils, the carambola cultivar Hua-Di always showed higher Cd tolerance than the other cultivars; however, this tendency was not confirmed by hydroponic experiment. The Cd BCFs of cultivar Thailand grown in soils with 6 and 12 mg Cd kg(-1) were highest among cultivars, whereas this trend was reversed at 120 mg Cd kg(-1) treatment. Nevertheless, the pot- and hydroponics-grown carambola cultivars generally showed higher capacities to tolerate and accumulate Cd, compared with the control species. The present results indicate that a strong ability to tolerate and accumulate Cd seems to be a trait at the species level in A. carambola, although some degree of variances in both Cd tolerance and accumulation exists among cultivars.

  16. Comparison of two ferns (Adiantum capillus-veneris Linn. and Microsorium punctatum (Linn.) Copel) for their Cr accumulation potential and antioxidant responses.

    PubMed

    Sinam, Geetgovind; Behera, Sandip K; Mishra, Rohit K; Sinha, Sarita; Mallick, Shekhar; Khare, P B

    2012-08-01

    Study was undertaken to compare Cr accumulation in two ferns (Adiantum capillus-veneris Linn. and Microsorium punctatum (Linn.) Copel) and the role of antioxidants were also investigated towards metal tolerance in order to assess the use of ferns in phytomediation/ phytostabilization. Different concentrations (0, 50, 100, 150 microg g(-1) dw) of Cr were added to fern planted in pot containing 1 kg soil. In both the ferns, Cr accumulation increased with increase in metal concentration and maximum accumulation of 800.5 microg g(-1) (fronds) and 1457.4 microg g(-1) (roots) in M. punctatum and 660.8 microg g(-1) (fronds) and 1259.6 microg g(-1) (roots) in A. capillus-veneris was recorded. The increase in the levels of malondialdehyde, antioxidants and antioxidant enzymes (superoxide dismutase, glutathione peroxidase) in A. capillus-veneris was less pronounced than M. punctatum under Cr exposure as compared to their respective controls. In view of less decrease in chlorophyll content and antioxidants along with higher accumulation of Cr in the fronds M. punctatum, is indicative of its higher tolerance towards Cr. However, bioaccumulation factor (concentration of Cr in fronds/concentration of Cr in the soil) of both the ferns was recorded > 1 which qualifies the plants as potential Cr hyperaccumulator and suitable for phytoremediaton.

  17. Trehalose reserve in Saccharomyces cerevisiae: phenomenon of transport, accumulation and role in cell viability.

    PubMed

    Plourde-Owobi, L; Durner, S; Goma, G; François, J

    2000-04-10

    Strains of Saccharomyces cerevisiae deleted for TPS1 encoding trehalose-6-phosphate synthase still accumulate trehalose when harbouring a functional MAL locus. We demonstrate that this accumulation results from an active uptake of trehalose present in the 'yeast extract' used to make the enriched culture media and that no accumulation is observed in mineral media. The uptake of trehalose was shown to be mediated by the alpha-glucoside transporter encoded by AGT1, the expression of which is linked to the presence of a functional MAL locus. Deletion of this gene in a MAL+ tps1 mutant abolished trehalose accumulation on a maltose or galactose mineral medium. However, small amounts of disaccharide were still detected in a agt1 tps1 double mutant when the medium was supplemented with 10 g trehalose l(-1), indicating the existence of a non-concentrative low-affinity sugar transporter. The presence of the high-affinity trehalose permease allowed us to investigate the effect of increasing exogenous trehalose from 0 to 10 g(-1) on intracellular accumulation. A maximum of ca. 10% (wt/wt dry cells) trehalose was attained in the presence of only 1 g l(-1) of disaccharide in the medium. The capability to monitor the intracellular content of trehalose by varying its extracellular concentration, independent of genetic alterations of the trehalose metabolic machinery, allowed the remarkable contribution of this molecule in stress tolerance to be demonstrated, as the higher the trehalose content, the longer the cell survival to a severe heat shock and to glucose starvation.

  18. Development of a liquid chromatography/mass spectrometry-based drug accumulation assay in Pseudomonas aeruginosa.

    PubMed

    Cai, Hongliang; Rose, Kelly; Liang, Lan-Hsin; Dunham, Steve; Stover, Charles

    2009-02-15

    Bacterial resistance to antibiotic therapy remains a worldwide problem. In Pseudomonasaeruginosa, rates of efflux confer inherent resistance to many antimicrobial agents, including fluoroquinolones, due to a high level of expression and a relatively high turnover number of the efflux pumps in gram-negative bacteria. To understand the roles of efflux pumps in both the influx and efflux of compounds in P. aeruginosa and to aid the chemistry compound design by bridging in vitro enzymatic binding data (IC(50) values) with whole cell results (MIC numbers), a collaborative effort was put forward to validate a series of bacterial penetration/accumulation assays for assessment of intracellular drug concentration. Initially, using 2-(4-dimethylaminostyryl)-1-ethylpyridinium cation (DMP) as the tracer, a 96-well fluorescence assay was established to measure the time-dependent accumulation of DMP in wild-type (PAO1), MexABOprM deletion (PAO200), and MexABOprM-MexCDOprJ-MexJKL:FRT deletion mutants (PAO314). At steady state, the order of DMP accumulation was PAO314>PAO200>PAO1. Subsequently, the established assay conditions were applied to a radiolabeled assay format using (3)H-labeled ciprofloxacin. At the concentration tested, the accumulation of [(3)H]ciprofloxacin approached a plateau after 15 min and the amount of accumulation in PAO314 was higher (~2- to 10-fold) than that in PAO1. Finally, with an additional step of cell lysis, a liquid chromatography/mass spectrometry-based assay was established with ciprofloxacin with (i) superior sensitivity (the detection limit can be as low as 0.24 ng/ml for ciprofloxacin) and (ii) the ability to monitor cold or nonfluorescent compounds in a drug discovery setting. PMID:19032927

  19. [Accumulation Characteristics and Evaluation of Heavy Metals in Soil-Crop System Affected by Wastewater Irrigation Around a Chemical Factory in Shenmu County].

    PubMed

    Qi, Yan-bing; Chu, Wan-lin; Pu, Jie; Liu, Meng-yun; Chang, Qing-rui

    2015-04-01

    Soil heavy metals Cu, Pb, Zn, and Cd, are regarded as "chemical time bombs" because of their propensity for accumulation in the soil and uptake by crops. This ultimately causes human toxicity in both the short and long-term, making farmland ecosystems dangerous to health. In this paper, accumulation and spatial variability of Cu, Zn, Pb and Cd in soil-crop system affected by wastewater irrigation around a chemical factor in northern Shaanxi province were analyzed. Results showed that wastewater irrigation around the chemical factory induced significant accumulation in soils compared with control areas. The average concentrations of available Cu and total Cu were 4.32 mg x kg(-1) and 38.4 mg x kg(-1), which were twice and 1.35 times higher than those of the control area, respectively. Soil Zn and Pb were slightly accumulated. Whereas soil Cd was significantly accumulated and was higher than the critical level of soil environmental quality (II), the available and total Cd concentrations were 0.248 mg x kg(-1) and 1.21 mg x kg(-1), which were 10 and 6.1 times higher than those of the control areas. No significant correlations were found between available and total heavy metals except between available Cd and total Cd. All the heavy metals were mainly accumulated in the top layer (0-10 cm). Spatially, soils and plants high in heavy metal concentration were distributed within the radius of about 100 m from the waste water outlet for Cu, Zn and Cd and about 200 m for Pb, and decreased exponentially with the distance from the factory. Affected by wastewater irrigation, contents of Cu, Pb and Cd in maize were 4.74, 0.129 and 0.036 mg x kg(-1) which were slightly higher than those in the control area. The content of Zn was similar to that in the control area. Affected by the vehicle exhaust, the over standard rate of Pb was 5.7% in maize. All the heavy metals did not show significant correlation between soil and crop, except Cd. The square correlation coefficients were 0

  20. [Accumulation Characteristics and Evaluation of Heavy Metals in Soil-Crop System Affected by Wastewater Irrigation Around a Chemical Factory in Shenmu County].

    PubMed

    Qi, Yan-bing; Chu, Wan-lin; Pu, Jie; Liu, Meng-yun; Chang, Qing-rui

    2015-04-01

    Soil heavy metals Cu, Pb, Zn, and Cd, are regarded as "chemical time bombs" because of their propensity for accumulation in the soil and uptake by crops. This ultimately causes human toxicity in both the short and long-term, making farmland ecosystems dangerous to health. In this paper, accumulation and spatial variability of Cu, Zn, Pb and Cd in soil-crop system affected by wastewater irrigation around a chemical factor in northern Shaanxi province were analyzed. Results showed that wastewater irrigation around the chemical factory induced significant accumulation in soils compared with control areas. The average concentrations of available Cu and total Cu were 4.32 mg x kg(-1) and 38.4 mg x kg(-1), which were twice and 1.35 times higher than those of the control area, respectively. Soil Zn and Pb were slightly accumulated. Whereas soil Cd was significantly accumulated and was higher than the critical level of soil environmental quality (II), the available and total Cd concentrations were 0.248 mg x kg(-1) and 1.21 mg x kg(-1), which were 10 and 6.1 times higher than those of the control areas. No significant correlations were found between available and total heavy metals except between available Cd and total Cd. All the heavy metals were mainly accumulated in the top layer (0-10 cm). Spatially, soils and plants high in heavy metal concentration were distributed within the radius of about 100 m from the waste water outlet for Cu, Zn and Cd and about 200 m for Pb, and decreased exponentially with the distance from the factory. Affected by wastewater irrigation, contents of Cu, Pb and Cd in maize were 4.74, 0.129 and 0.036 mg x kg(-1) which were slightly higher than those in the control area. The content of Zn was similar to that in the control area. Affected by the vehicle exhaust, the over standard rate of Pb was 5.7% in maize. All the heavy metals did not show significant correlation between soil and crop, except Cd. The square correlation coefficients were 0

  1. Heavy metal accumulation in lichens growing in north side of Lucknow city, India.

    PubMed

    Saxena, Shalini; Upreti, D K; Sharma, Neeta

    2007-01-01

    Accumulation of Pb, Fe, Cr, Zn, Cd, Ni, Cu and Hg metals in six common lichen species growing on Mangifera indica trees in mango orchard surrounding the north side of the Lucknow city, were analyzed. The study revealed the higher concentration of Pb (3.3 - 15.6 microgg(-1)), Cr (25.6 - 137.5 microgg(-1)), Zn (49.4 - 219.7 microgg(-1)), Cu (10.2 - 66.6 microgg(-1)) and Fe (1748 - 19374 microgg(-1)). PMID:17717985

  2. Uptake and Accumulation of Pharmaceuticals in Lettuce Under Surface and Overhead Irrigations

    NASA Astrophysics Data System (ADS)

    Bhalsod, G.; Chuang, Y. H.; Jeon, S.; Gui, W.; Li, H.; Guber, A.; Zhang, W.

    2015-12-01

    Pharmaceuticals and personal care products are being widely detected in wastewater and surface waters. As fresh water becomes scarcer, interests in using reclaimed water for crop irrigation is intensified. Since reclaimed waters often carry trace levels of pharmaceuticals, accumulation of pharmaceuticals in food crops could increase the risk of human exposure. This study aims to investigate uptake and accumulations of pharmaceuticals in greenhouse-grown lettuce under contrasting irrigation practices (i.e., overhead and surface irrigations). Lettuce was irrigated with water spiked with 11 commonly used pharmaceuticals (acetaminophen, caffeine, carbamazepine, sulfadiazine, sulfamethoxazole, carbadox, trimethoprim, lincomycin hydrochloride, oxytetracycline hydrochloride, monensin sodium, and tylosin). Weekly sampling of lettuce roots, shoots, and soils were continued for 5 weeks, and the samples were freeze dried, extracted for pharmaceuticals and analyzed by LC-MS/MS. Preliminary results indicate that higher concentrations of pharmaceuticals were found in overhead irrigated lettuce compared to surface irrigated lettuce. For carbamezapine, sulfadiazine, trimethoprim, oxytetracycline, and monensin sodium, their concentrations generally increased in lettuce shoots in the overhead treatment over time. However, acetaminophen was found at higher concentrations in both shoots and roots, indicating that acetaminophen can be easily transported in the plant system. This study provides insight on developing better strategies for using reclaimed water for crop irrigations, while minimizing the potential risks of pharmaceutical contamination of vegetables.

  3. [Effect of precursor on growth and accumulation of alkaloids of Lycoris radiata suspension cells].

    PubMed

    Zhang, Yuqiong; Li, Yong; Zhou, Jianhui; Chen, Na; Wang, Meifang; Dong, Zhaorong; Gao, Cuiyun; Zhong, Yanlong

    2014-02-01

    In order to investigate the effects of phenylalanine, tyrosine and tyramine on the growth of Lycoris radiata suspension cells and the accumulation of alkaloids, the growth quantity of the cells as well as the content of alkaloids in cells were determined, which were treated with above three kinds of precursors alone and phenylalanine combined with tyrosine respectively. The results indicate that the addition of phenylalanine alone and addition of phenylalanine on the basis of tyrosine at high concentration (200 micromol/L) had no significant effect on the growth of Lycoris radiata suspension cells and the content of alkaloids in cells; whereas tyrosine and tyramine promoted the growth of the cells and alkaloids accumulation. Treated with tyrosine at high concentration (200 micromol/L), the content of alkaloids of the cells was 2.56-fold higher than that of the control group, the amounts of lycoramine (3.77 mg/g) and galanthamine (4.46 mg/g) were 6.61-fold and 6.97-fold higher than that of the control group, respectively. When treated with tyramine (200 micromol/L), the amount of alkaloids in Lycoris radiata suspension cells was 2.63-fold higher than that of the control group, and the amounts of lycoramine (4.45 mg/g) and galanthamine (5.14 mg/g) were 9.08-fold and 9.18-fold higher than that of the control group, respectively. The above results demonstrate that adding tyrosine and tyramine in the media significantly promoted the growth of the Lycoris radiata suspension cells and alkaloids accumulation in the cells. PMID:24945053

  4. Differences in organotin accumulation among ecological migratory types of the Japanese eel Anguilla japonica

    NASA Astrophysics Data System (ADS)

    Ohji, Madoka; Harino, Hiroya; Arai, Takaomi

    2006-08-01

    In order to examine the ecological risks caused by organotin compounds (OTs) in diadromous fish migrating between sea and freshwater, tributyltin (TBT) and triphenyltin (TPT) compounds, and their breakdown products, were determined in the catadromous eel Anguilla japonica having sea, estuarine and river life histories, collected in Japanese sea, brackish and fresh waters. Ontogenic changes in otolith strontium (Sr) and calcium (Ca) concentrations were examined along life history transect to discriminate the migration type. There were generally three different patterns, which were categorized 'sea eels' (spent most of their life in the sea and did not enter freshwater), 'estuarine eels' (inhabited estuaries or switched between different habitats), and 'river eels' (entered and remained in freshwater river habitats after arrival in the estuary) according to the otolith Sr:Ca ratio. There were generally no significant correlations between TBT and TPT accumulation and various biological characteristics such as total length (TL), body weight (BW), age and sex in A. japonica. The concentrations of TBT and TPT in silver eels (mature eels) were significantly higher than those in yellow eels (immature eels), and the percentages of TBT and TPT were also higher in silver eels than in yellow eels. A positive correlation was found between TBT concentration and the gonad-somatic index (GSI). It is thus considered that silver eels have a higher risk of contamination by TBT than yellow eels. TBT and TPT concentrations in sea eels were significantly higher than those in river eels. In contrast, no significant differences were observed in TBT and TPT concentrations in estuarine eels compared to sea and river eels. These results suggest that sea eels have a higher ecological risk of OT contamination than river eels during their life history, and the risk of OTs in estuarine eels is considered to be intermediate between that of sea and river eels. Positive linear relationships were

  5. Ocean acidification increases the accumulation of toxic phenolic compounds across trophic levels

    PubMed Central

    Jin, Peng; Wang, Tifeng; Liu, Nana; Dupont, Sam; Beardall, John; Boyd, Philip W.; Riebesell, Ulf; Gao, Kunshan

    2015-01-01

    Increasing atmospheric CO2 concentrations are causing ocean acidification (OA), altering carbonate chemistry with consequences for marine organisms. Here we show that OA increases by 46–212% the production of phenolic compounds in phytoplankton grown under the elevated CO2 concentrations projected for the end of this century, compared with the ambient CO2 level. At the same time, mitochondrial respiration rate is enhanced under elevated CO2 concentrations by 130–160% in a single species or mixed phytoplankton assemblage. When fed with phytoplankton cells grown under OA, zooplankton assemblages have significantly higher phenolic compound content, by about 28–48%. The functional consequences of the increased accumulation of toxic phenolic compounds in primary and secondary producers have the potential to have profound consequences for marine ecosystem and seafood quality, with the possibility that fishery industries could be influenced as a result of progressive ocean changes. PMID:26503801

  6. Ocean acidification increases the accumulation of toxic phenolic compounds across trophic levels.

    PubMed

    Jin, Peng; Wang, Tifeng; Liu, Nana; Dupont, Sam; Beardall, John; Boyd, Philip W; Riebesell, Ulf; Gao, Kunshan

    2015-10-27

    Increasing atmospheric CO2 concentrations are causing ocean acidification (OA), altering carbonate chemistry with consequences for marine organisms. Here we show that OA increases by 46-212% the production of phenolic compounds in phytoplankton grown under the elevated CO2 concentrations projected for the end of this century, compared with the ambient CO2 level. At the same time, mitochondrial respiration rate is enhanced under elevated CO2 concentrations by 130-160% in a single species or mixed phytoplankton assemblage. When fed with phytoplankton cells grown under OA, zooplankton assemblages have significantly higher phenolic compound content, by about 28-48%. The functional consequences of the increased accumulation of toxic phenolic compounds in primary and secondary producers have the potential to have profound consequences for marine ecosystem and seafood quality, with the possibility that fishery industries could be influenced as a result of progressive ocean changes.

  7. Ocean acidification increases the accumulation of toxic phenolic compounds across trophic levels

    NASA Astrophysics Data System (ADS)

    Jin, Peng; Wang, Tifeng; Liu, Nana; Dupont, Sam; Beardall, John; Boyd, Philip W.; Riebesell, Ulf; Gao, Kunshan

    2015-10-01

    Increasing atmospheric CO2 concentrations are causing ocean acidification (OA), altering carbonate chemistry with consequences for marine organisms. Here we show that OA increases by 46-212% the production of phenolic compounds in phytoplankton grown under the elevated CO2 concentrations projected for the end of this century, compared with the ambient CO2 level. At the same time, mitochondrial respiration rate is enhanced under elevated CO2 concentrations by 130-160% in a single species or mixed phytoplankton assemblage. When fed with phytoplankton cells grown under OA, zooplankton assemblages have significantly higher phenolic compound content, by about 28-48%. The functional consequences of the increased accumulation of toxic phenolic compounds in primary and secondary producers have the potential to have profound consequences for marine ecosystem and seafood quality, with the possibility that fishery industries could be influenced as a result of progressive ocean changes.

  8. Comparative Study of Lead Concentration in Feathers of Urban and Rural Passerines in Merida, Mexico.

    PubMed

    Nava-Diaz, Remedios; Hoogesteijn, Almira L; Erosa, Mercy Dzul; Febles, Jose L; Mendez-Gonzalez, Rosa M

    2015-10-01

    Lead is a commonly monitored heavy metal because of potential health effects on exposed organisms. We quantified lead in secondary feathers of two passerine bird species, clay-colored thrushes (Turdus grayi) and great-tailed grackles (Quiscalus mexicanus), from an urban and a rural site in the municipality of Merida, Yucatan. Urban lead concentration was significantly higher than its rural counterpart for both species (p < 0.05). In the urban site, lead concentration was similar in both species (p = 0.14). However, data from the rural site showed that lead concentration was significantly higher in thrush feathers (p < 0.05). Lead levels herein presented are among the lowest ever reported suggesting that either lead accumulation or absorption is limited. Finally, our data seem to support the hypothesis that species feeding ecology plays a major role in lead accumulation. PMID:26253842

  9. Comparative Study of Lead Concentration in Feathers of Urban and Rural Passerines in Merida, Mexico.

    PubMed

    Nava-Diaz, Remedios; Hoogesteijn, Almira L; Erosa, Mercy Dzul; Febles, Jose L; Mendez-Gonzalez, Rosa M

    2015-10-01

    Lead is a commonly monitored heavy metal because of potential health effects on exposed organisms. We quantified lead in secondary feathers of two passerine bird species, clay-colored thrushes (Turdus grayi) and great-tailed grackles (Quiscalus mexicanus), from an urban and a rural site in the municipality of Merida, Yucatan. Urban lead concentration was significantly higher than its rural counterpart for both species (p < 0.05). In the urban site, lead concentration was similar in both species (p = 0.14). However, data from the rural site showed that lead concentration was significantly higher in thrush feathers (p < 0.05). Lead levels herein presented are among the lowest ever reported suggesting that either lead accumulation or absorption is limited. Finally, our data seem to support the hypothesis that species feeding ecology plays a major role in lead accumulation.

  10. Saturating Light Induces Sustained Accumulation of Oil in Plastidal Lipid Droplets in Chlamydomonas reinhardtii.

    PubMed

    Goold, Hugh Douglas; Cuiné, Stéphan; Légeret, Bertrand; Liang, Yuanxue; Brugière, Sabine; Auroy, Pascaline; Javot, Hélène; Tardif, Marianne; Jones, Brian; Beisson, Fred; Peltier, Gilles; Li-Beisson, Yonghua

    2016-08-01

    Enriching algal biomass in energy density is an important goal in algal biotechnology. Nitrogen (N) starvation is considered the most potent trigger of oil accumulation in microalgae and has been thoroughly investigated. However, N starvation causes the slow down and eventually the arrest of biomass growth. In this study, we show that exposing a Chlamydomonas reinhardtii culture to saturating light (SL) under a nonlimiting CO2 concentration in turbidostatic photobioreactors induces a sustained accumulation of lipid droplets (LDs) without compromising growth, which results in much higher oil productivity than N starvation. We also show that the polar membrane lipid fraction of SL-induced LDs is rich in plastidial lipids (approximately 70%), in contrast to N starvation-induced LDs, which contain approximately 60% lipids of endoplasmic reticulum origin. Proteomic analysis of LDs isolated from SL-exposed cells identified more than 200 proteins, including known proteins of lipid metabolism, as well as 74 proteins uniquely present in SL-induced LDs. LDs induced by SL and N depletion thus differ in protein and lipid contents. Taken together, lipidomic and proteomic data thus show that a large part of the sustained oil accumulation occurring under SL is likely due to the formation of plastidial LDs. We discuss our data in relation to the different metabolic routes used by microalgae to accumulate oil reserves depending on cultivation conditions. Finally, we propose a model in which oil accumulation is governed by an imbalance between photosynthesis and growth, which can be achieved by impairing growth or by boosting photosynthetic carbon fixation, with the latter resulting in higher oil productivity. PMID:27297678

  11. Influence of diet in the accumulation of organochlorine compounds in herons breeding in remote riverine environments.

    PubMed

    Huertas, David; Grimalt, Joan O; Jover, Lluis; Sanpera, Carola

    2016-02-01

    The composition of organochlorine compounds (OCs), pentachlorobenzene (PeCB), hexachlorobenzene (HCB), hexachlorocyclohexanes (HCHs), DDTs and polychlorobiphenyls (PCBs), has been analyzed in eggs from cattle egret (Bubulcus ibis) and little egret (Egretta garzetta), two species of herons (family Ardeidae), nesting at the same remote riverine environment (Aiguabarreig, Ebro River). These two species were selected to evaluate the importance of diet in the accumulation of OCs. Cattle egret essentially feeds on dry grassy habitats and follow cattle or other large animals whereas little egret feeds on fish, amphibians and crustaceans captured in shallow waters. The δ(15)N and δ(13)C isotopic composition of the sampled eggs was studied and the results were consistent with these species feeding habits. In both species, the compounds accumulated the most were the less volatile and more lipophilic, e.g. PCB congeners of higher chlorination, DDT and metabolites. The distinct foraging species preferences were reflected in significant higher concentrations in little egret than cattle egret of all pollutant groups analysed. These differences were statistically significant for DDTs and PCBs (p < 0.015 and p < 0.047, respectively), e.g. the p,p'-DDE and PCB concentrations were 6 and 4.5 times higher, respectively, in the former than the latter. This strong contrast indicates that in remote environments aquatic riverine ecosystems are more efficient OC reservoirs than the terrestrial ecosystem.

  12. Perfluorooctane sulfonate toxicity, isomer-specific accumulation, and maternal transfer in zebrafish (Danio rerio) and rainbow trout (Oncorhynchus mykiss).

    PubMed

    Sharpe, Rainie L; Benskin, Jonathan P; Laarman, Anne H; Macleod, Sherri L; Martin, Jonathan W; Wong, Charles S; Goss, Greg G

    2010-09-01

    Perfluorooctane sulfonate (PFOS; C(8)F(17)SO(3) (-)) bioaccumulation and toxicity have been demonstrated in both aquatic and terrestrial organisms. The majority of investigations have examined total PFOS concentrations in wildlife and in toxicity testing, but isomer-specific monitoring studies are less common, and no laboratory-based study of PFOS isomer accumulation in fish has been reported. The present study examined accumulation and maternal transfer of PFOS isomers in zebrafish and tissue-specific accumulation of PFOS isomers in trout parr. A median lethal dose (LC50) of 22.2 and 2.5 mg/L was calculated for adult zebrafish and trout parr, respectively. A two-week PFOS exposure resulted in tissue-specific PFOS accumulation in trout, with maximum concentrations identified in the liver tissue (>50 microg/g). Prior exposure to PFOS as alevin did not affect the accumulation of PFOS in tissues later in life. In both species, accumulation of branched PFOS isomers generally occurred to a lesser extent than linear PFOS, which may explain the relative deficiency of branched PFOS isomers in some aquatic species in the field. Analysis of exposed trout tissues indicated that isomer discrimination may occur at the level of elimination or uptake and elimination processes in the kidney or gill, respectively. When zebrafish underwent a reproductive cycle in the presence of PFOS, approximately 10% (wt) of the adult PFOS body burden was transferred to the developing embryos, resulting in a higher total PFOS concentration in eggs (116 +/- 13.3 microg/g) than in the parent fish (72.1 +/- 7.6 m