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Sample records for accumulated significantly higher

  1. Significant silicon accumulation by marine picocyanobacteria

    NASA Astrophysics Data System (ADS)

    Baines, Stephen B.; Twining, Benjamin S.; Brzezinski, Mark A.; Krause, Jeffrey W.; Vogt, Stefan; Assael, Dylan; McDaniel, Hannah

    2012-12-01

    The marine silicon cycle is thought to be intimately tied to the carbon cycle through its effect on the growth of diatoms. These unicellular algae form substantial blooms in cold, nutrient-rich waters. Their dense, siliceous cell walls promote the sinking of particulate matter, and all the carbon and nutrients contained therein. As such, diatoms are thought to be the primary organisms responsible for the low levels of dissolved silicon observed in the surface ocean and the export of mineral silica to depth. Here, we use synchrotron X-ray fluorescence microscopy to determine the elemental composition of individual diatoms and cyanobacterial cells from the eastern equatorial Pacific and the Sargasso Sea. We show that cells of Synechococcus, a small unicellular marine cyanobacterium that dominates in nutrient-depleted waters, can exhibit cellular ratios of silicon to sulphur, and silicon to phosphorus, approaching those detected in diatoms in the same location. Silicon accumulation was also observed in cultured Synechococcus strains. We estimate that the water column inventory of silicon in Synechococcus can exceed that of diatoms in some cases. We suggest that picocyanobacteria may exert a previously unrecognized influence on the oceanic silicon cycle, especially in nutrient-poor waters.

  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. Competitive Intelligence: Significance in Higher Education

    ERIC Educational Resources Information Center

    Barrett, Susan E.

    2010-01-01

    Historically noncompetitive, the higher education sector is now having to adjust dramatically to new and increasing demands on numerous levels. To remain successfully operational within the higher educational market universities today must consider all relevant forces which can impact present and future planning. Those institutions that were…

  5. Significant accumulation of nitrate in Chinese semi-humid croplands

    NASA Astrophysics Data System (ADS)

    Zhou, Junyu; Gu, Baojing; Schlesinger, William H.; Ju, Xiaotang

    2016-04-01

    Soil nitrate is important for crop growth, but it can also leach to groundwater causing nitrate contamination, a threat to human health. Here, we report a significant accumulation of soil nitrate in Chinese semi-humid croplands based upon more than 7000 samples from 141 sites collected from 1994 to 2015. In the 0–4 meters depth of soil, total nitrate accumulation reaches 453 ± 39, 749 ± 75, 1191 ± 89, 1269 ± 114, 2155 ± 330 kg N ha‑1 on average in wheat, maize, open-field vegetables (OFV), solar plastic-roofed greenhouse vegetables (GHV) and orchard fields, respectively. Surprisingly, there is also a comparable amount of nitrate accumulated in the vadose-zone deeper than 4 meters. Over-use of N fertilizer (and/or manure) and a declining groundwater table are the major causes for this huge nitrate reservoir in the vadose-zone of semi-humid croplands, where the nitrate cannot be denitrified due to the presence of oxygen and lack of carbon sources. Future climatic change with more extreme rainfall events would increase the risk of accumulated nitrate moving downwards and threatening groundwater nitrate contamination.

  6. Significant accumulation of nitrate in Chinese semi-humid croplands

    PubMed Central

    Zhou, Junyu; Gu, Baojing; Schlesinger, William H.; Ju, Xiaotang

    2016-01-01

    Soil nitrate is important for crop growth, but it can also leach to groundwater causing nitrate contamination, a threat to human health. Here, we report a significant accumulation of soil nitrate in Chinese semi-humid croplands based upon more than 7000 samples from 141 sites collected from 1994 to 2015. In the 0–4 meters depth of soil, total nitrate accumulation reaches 453 ± 39, 749 ± 75, 1191 ± 89, 1269 ± 114, 2155 ± 330 kg N ha−1 on average in wheat, maize, open-field vegetables (OFV), solar plastic-roofed greenhouse vegetables (GHV) and orchard fields, respectively. Surprisingly, there is also a comparable amount of nitrate accumulated in the vadose-zone deeper than 4 meters. Over-use of N fertilizer (and/or manure) and a declining groundwater table are the major causes for this huge nitrate reservoir in the vadose-zone of semi-humid croplands, where the nitrate cannot be denitrified due to the presence of oxygen and lack of carbon sources. Future climatic change with more extreme rainfall events would increase the risk of accumulated nitrate moving downwards and threatening groundwater nitrate contamination. PMID:27114032

  7. Significant accumulation of nitrate in Chinese semi-humid croplands.

    PubMed

    Zhou, Junyu; Gu, Baojing; Schlesinger, William H; Ju, Xiaotang

    2016-01-01

    Soil nitrate is important for crop growth, but it can also leach to groundwater causing nitrate contamination, a threat to human health. Here, we report a significant accumulation of soil nitrate in Chinese semi-humid croplands based upon more than 7000 samples from 141 sites collected from 1994 to 2015. In the 0-4 meters depth of soil, total nitrate accumulation reaches 453 ± 39, 749 ± 75, 1191 ± 89, 1269 ± 114, 2155 ± 330 kg N ha(-1) on average in wheat, maize, open-field vegetables (OFV), solar plastic-roofed greenhouse vegetables (GHV) and orchard fields, respectively. Surprisingly, there is also a comparable amount of nitrate accumulated in the vadose-zone deeper than 4 meters. Over-use of N fertilizer (and/or manure) and a declining groundwater table are the major causes for this huge nitrate reservoir in the vadose-zone of semi-humid croplands, where the nitrate cannot be denitrified due to the presence of oxygen and lack of carbon sources. Future climatic change with more extreme rainfall events would increase the risk of accumulated nitrate moving downwards and threatening groundwater nitrate contamination. PMID:27114032

  8. Significant accumulation of nitrate in Chinese semi-humid croplands.

    PubMed

    Zhou, Junyu; Gu, Baojing; Schlesinger, William H; Ju, Xiaotang

    2016-01-01

    Soil nitrate is important for crop growth, but it can also leach to groundwater causing nitrate contamination, a threat to human health. Here, we report a significant accumulation of soil nitrate in Chinese semi-humid croplands based upon more than 7000 samples from 141 sites collected from 1994 to 2015. In the 0-4 meters depth of soil, total nitrate accumulation reaches 453 ± 39, 749 ± 75, 1191 ± 89, 1269 ± 114, 2155 ± 330 kg N ha(-1) on average in wheat, maize, open-field vegetables (OFV), solar plastic-roofed greenhouse vegetables (GHV) and orchard fields, respectively. Surprisingly, there is also a comparable amount of nitrate accumulated in the vadose-zone deeper than 4 meters. Over-use of N fertilizer (and/or manure) and a declining groundwater table are the major causes for this huge nitrate reservoir in the vadose-zone of semi-humid croplands, where the nitrate cannot be denitrified due to the presence of oxygen and lack of carbon sources. Future climatic change with more extreme rainfall events would increase the risk of accumulated nitrate moving downwards and threatening groundwater nitrate contamination.

  9. The significance of the accumulation of cadmium by aquatic organisms

    SciTech Connect

    Taylor, D.

    1983-02-01

    Cadmium, by virtue of its toxicity, persistence, and bioaccumulation appears on the ''black list'' of all the international conventions aimed at protecting the aquatic environment from pollution. Although there is no doubt that cadmium is both persistent and toxic to aquatic life at relatively low concentrations, its bioaccumulation potential appears to have been somewhat exaggerated. Median concentration factors for both marine and freshwater organisms are less than 100 times and for vertebrate (fish) species concentration factors are less than 20 times. There is no evidence in the literature for biomagnification of cadmium and bioconcentration is only likely to be of significance in a restricted range of gastropod mollusks and some crustacea.

  10. Regenerative capacity of old muscle stem cells declines without significant accumulation of DNA damage.

    PubMed

    Cousin, Wendy; Ho, Michelle Liane; Desai, Rajiv; Tham, Andrea; Chen, Robert Yuzen; Kung, Sunny; Elabd, Christian; Conboy, Irina M

    2013-01-01

    The performance of adult stem cells is crucial for tissue homeostasis but their regenerative capacity declines with age, leading to failure of multiple organs. In skeletal muscle this failure is manifested by the loss of functional tissue, the accumulation of fibrosis, and reduced satellite cell-mediated myogenesis in response to injury. While recent studies have shown that changes in the composition of the satellite cell niche are at least in part responsible for the impaired function observed with aging, little is known about the effects of aging on the intrinsic properties of satellite cells. For instance, their ability to repair DNA damage and the effects of a potential accumulation of DNA double strand breaks (DSBs) on their regenerative performance remain unclear. This work demonstrates that old muscle stem cells display no significant accumulation of DNA DSBs when compared to those of young, as assayed after cell isolation and in tissue sections, either in uninjured muscle or at multiple time points after injury. Additionally, there is no significant difference in the expression of DNA DSB repair proteins or globally assayed DNA damage response genes, suggesting that not only DNA DSBs, but also other types of DNA damage, do not significantly mark aged muscle stem cells. Satellite cells from DNA DSB-repair-deficient SCID mice do have an unsurprisingly higher level of innate DNA DSBs and a weakened recovery from gamma-radiation-induced DNA damage. Interestingly, they are as myogenic in vitro and in vivo as satellite cells from young wild type mice, suggesting that the inefficiency in DNA DSB repair does not directly correlate with the ability to regenerate muscle after injury. Overall, our findings suggest that a DNA DSB-repair deficiency is unlikely to be a key factor in the decline in muscle regeneration observed upon aging.

  11. 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'.

  12. 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…

  13. Nitrogen and metals in two regions in Central Europe: significant differences in accumulation in mosses due to land use?

    PubMed

    Schröder, Winfried; Hornsmann, Inga; Pesch, Roland; Schmidt, Gunther; Markert, Bernd; Fränzle, Stefan; Wünschmann, Simone; Heidenreich, Heike

    2007-10-01

    The study was conducted to test the hypothesis that the regional variability of nitrogen (N) and metal accumulations in terrestrial ecosystems are due to historical and recent ways of landuse. To this end, two regions of Central Europe were selected for investigation: the Weser-Ems Region (WER) and the Euro Region Nissa (ERN). They were assumed to have land use-specific accumulation profiles. Thus, the metal and N accumulations in both regions were examined by means of geostatistically based comparative moss analysis. The sampling and chemical analysis of mosses were conducted in accordance with the convenient guidelines and methods, respectively. The spatial representativity of the sampling sites was computed by means of a land classification which was calculated for Europe by means of classification trees and GIS-techniques. The differences of deposition loads were tested for statistical significance with regard to time and space. The measurement values corroborated the decline of metal accumulation observed since the beginning of the European Metals in Mosses Surveys in 1990. The metal loads of the mosses in the ERN exceeded those in the WER significantly. The opposite holds true for the N concentrations: those in the WER were significantly higher than those in the ERN. The reduction of emissions from power plants, factories and houses was strongly correlated with the decline of deposition and bioaccumulation of metals. As proved by the European Metals in Mosses Surveys, this tendency is due to successful environmental policies. But no such success could be verified by monitoring the accumulation of N in mosses.

  14. Palmitate induces insulin resistance without significant intracellular triglyceride accumulation in HepG2 cells.

    PubMed

    Lee, Jin-young; Cho, Hyang-Ki; Kwon, Young Hye

    2010-07-01

    Previous studies showed that increased release of free fatty acids from adipocytes leads to insulin resistance and triglyceride (TG) accumulation in the liver, which may progress into hepatic steatohepatitis. We and other investigators have previously reported that palmitate induces endoplasmic reticulum stress-mediated toxicity in several tissues. This work investigated whether palmitate could induce insulin resistance and steatosis in HepG2 cells. We treated cells with either saturated fatty acid (palmitate) or unsaturated fatty acid (oleate), and observed that palmitate significantly activated c-jun N-terminal kinase and inactivated protein kinase B. Both 4-phenylbutyric acid and glycerol significantly activated protein kinase B, confirming the involvement of endoplasmic reticulum stress in palmitate-mediated insulin resistance. Oleate, but not palmitate, significantly induced intracellular TG deposition and activated sterol regulatory element binding protein-1. Instead, diacylglycerol level and protein kinase C epsilon activity were significantly increased by palmitate, suggesting the possible role of diacylglycerol in palmitate-mediated lipotoxicity. Therefore, the present study clearly showed that palmitate impairs insulin resistance, but does not induce significant TG accumulation in HepG2 cells. PMID:20006364

  15. 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.

  16. Significant associations between hemostatic/fibrinolytic systems and accumulation of cardiovascular risk factors in Japanese elementary schoolchildren.

    PubMed

    Lin, Lisheng; Horigome, Hitoshi; Kato, Yoshiaki; Kikuchi, Toshihiro; Nakahara, Satoko; Sumazaki, Ryo

    2015-01-01

    The aim of this study was to establish the reference values of hemostatic/fibrinolytic markers and investigate their relationship with physical constitution and cardiovascular risk factors in a normal schoolchildren population. This study comprised 148 healthy Japanese children aged 9-10 years (males 73; females 75). We performed laboratory tests including blood levels of leptin, high-sensitive C-reactive protein (hs-CRP), hemostatic and fibrinolytic markers [plasminogen activator inhibitor 1 (PAI-1), coagulation factor VII (FVII), coagulation factor X (FX), fibrinogen (Fbg), protein C, protein S], as well as common biochemical markers in the morning after an overnight fast. We investigated the mean, 10th, 50th and 90th percentile values of these markers. All parameters were compared between two groups, that is those with body mass index (BMI) 90th percentile or higher and BMI less than 90th percentile, and between subgroups based on the number of cardiovascular risk factors. Multiple-linear regression was used to assess associations between these hematological parameters and the components related to metabolic syndrome (MetS). Alanine aminotransferase (ALT), uric acid, leptin, hs-CRP, and all hemostatic/fibrinolytic markers (PAI-1, FVII, FX, Fbg, protein C, protein S) tested were significantly higher in the group with BMI 90th percentile or higher, and increased with accumulation of cardiovascular risk factors. Multiple-linear regression analysis showed that these values were associated with one or more components related to MetS. Reference values of hemostatic/fibrinolytic markers in Japanese schoolchildren were obtained. Many hemostatic/fibrinolytic markers showed significant association with BMI and accumulation of cardiovascular risk factors in normal Japanese schoolchildren. PMID:25185676

  17. 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.

  18. Accumulation of Th, Pb, U, and Ra in marine phytoplankton and its geochemical significance

    SciTech Connect

    Fisher, N.S.; Teyssie, J.L.; Krishnaswami, S.; Baskaran, M.

    1987-01-01

    The bioaccumulation of U, Th, Ra, and Pb in four diverse nanoplanktonic algal species and a picoplanktonic blue-green alga was determined with radiotracers. Among the nanoplankton, differences of 1-2 orders of magnitude in volume/volume concentration factors (VCFs) were observed for a given nuclide, but larger differences were observed among the four nuclides, with VCF values of Th > Pb > Ra approx. U. The picoplankton cells, with greater surface:volume ratios, had significantly higher VCF values. The mean VCF values in the nanoplankton of Th and Pb were 1.5 x 10/sup 5/ and 3.6 x 10/sup 4/ in the light and 2.8 x 10/sup 4/ in the dark. The VCFs of Th and Pb in the picoplankton were both about 2 x 10/sup 6/, irrespective of light. Retention half-times of /sup 228/Th and /sup 210/Pb in fecal pellets of Artemia salina, fed radiolabeled diatoms, were 20-50 d, but > 120 d for /sup 228/Th at 4/sup 0/C. The results suggest that sinking plankton and their debris could account for most of the natural series radionuclides sedimenting out of oceanic surface waters.

  19. Overexpression of rice glutaredoxins (OsGrxs) significantly reduces arsenite accumulation by maintaining glutathione pool and modulating aquaporins in yeast.

    PubMed

    Verma, Pankaj Kumar; Verma, Shikha; Meher, Alok Kumar; Pande, Veena; Mallick, Shekhar; Bansiwal, Amit Kumar; Tripathi, Rudra Deo; Dhankher, Om Parkash; Chakrabarty, Debasis

    2016-09-01

    Arsenic (As) is an acute poison and class I carcinogen, can cause a serious health risk. Staple crops like rice are the primary source of As contamination in human food. Rice grown on As contaminated areas accumulates higher As in their edible parts. Based on our previous transcriptome data, two rice glutaredoxins (OsGrx_C7 and OsGrx_C2.1) were identified that showed up-regulated expression during As stress. Here, we report OsGrx_C7 and OsGrx_C2.1 from rice involved in the regulation of intracellular arsenite (AsIII). To elucidate the mechanism of OsGrx mediated As tolerance, both OsGrxs were cloned and expressed in Escherichia coli (Δars) and Saccharomyces cerevisiae mutant strains (Δycf1, Δacr3). The expression of OsGrxs increased As tolerance in E. coli (Δars) mutant strain (up to 4 mM AsV and up to 0.6 mM AsIII). During AsIII exposure, S. cerevisiae (Δacr3) harboring OsGrx_C7 and OsGrx_C2.1 have lower intracellular AsIII accumulation (up to 30.43% and 24.90%, respectively), compared to vector control. Arsenic accumulation in As-sensitive S. cerevisiae mutant (Δycf1) also reduced significantly on exposure to inorganic As. The expression of OsGrxs in yeast maintained intracellular GSH pool and increased extracellular GSH concentration. Purified OsGrxs displays in vitro GSH-disulfide oxidoreductase, glutathione reductase and arsenate reductase activities. Also, both OsGrxs are involved in AsIII extrusion by altering the Fps1 transcripts in yeast and protect the cell by maintaining cellular GSH pool. Thus, our results strongly suggest that OsGrxs play a crucial role in the maintenance of the intracellular GSH pool and redox status of the cell during both AsV and AsIII stress and might be involved in regulating intracellular AsIII levels by modulation of aquaporin expression and functions. PMID:27174139

  20. Overexpression of rice glutaredoxins (OsGrxs) significantly reduces arsenite accumulation by maintaining glutathione pool and modulating aquaporins in yeast.

    PubMed

    Verma, Pankaj Kumar; Verma, Shikha; Meher, Alok Kumar; Pande, Veena; Mallick, Shekhar; Bansiwal, Amit Kumar; Tripathi, Rudra Deo; Dhankher, Om Parkash; Chakrabarty, Debasis

    2016-09-01

    Arsenic (As) is an acute poison and class I carcinogen, can cause a serious health risk. Staple crops like rice are the primary source of As contamination in human food. Rice grown on As contaminated areas accumulates higher As in their edible parts. Based on our previous transcriptome data, two rice glutaredoxins (OsGrx_C7 and OsGrx_C2.1) were identified that showed up-regulated expression during As stress. Here, we report OsGrx_C7 and OsGrx_C2.1 from rice involved in the regulation of intracellular arsenite (AsIII). To elucidate the mechanism of OsGrx mediated As tolerance, both OsGrxs were cloned and expressed in Escherichia coli (Δars) and Saccharomyces cerevisiae mutant strains (Δycf1, Δacr3). The expression of OsGrxs increased As tolerance in E. coli (Δars) mutant strain (up to 4 mM AsV and up to 0.6 mM AsIII). During AsIII exposure, S. cerevisiae (Δacr3) harboring OsGrx_C7 and OsGrx_C2.1 have lower intracellular AsIII accumulation (up to 30.43% and 24.90%, respectively), compared to vector control. Arsenic accumulation in As-sensitive S. cerevisiae mutant (Δycf1) also reduced significantly on exposure to inorganic As. The expression of OsGrxs in yeast maintained intracellular GSH pool and increased extracellular GSH concentration. Purified OsGrxs displays in vitro GSH-disulfide oxidoreductase, glutathione reductase and arsenate reductase activities. Also, both OsGrxs are involved in AsIII extrusion by altering the Fps1 transcripts in yeast and protect the cell by maintaining cellular GSH pool. Thus, our results strongly suggest that OsGrxs play a crucial role in the maintenance of the intracellular GSH pool and redox status of the cell during both AsV and AsIII stress and might be involved in regulating intracellular AsIII levels by modulation of aquaporin expression and functions.

  1. Pattern of annual snow accumulation along a west Greenland flow line: no significant change observed during recent decades

    NASA Astrophysics Data System (ADS)

    Anklin, Martin; Stauffer, Bernhard; Geis, Klaus; Wagenbach, Dietmar

    1994-09-01

    At 10 positions on a traverse along a West Greenland flow line, shallow drillings and pit studies were performed in summer 1990. Continuous in situ hydrogen peroxide analyses on these samples allowed the seasonal firn stratigraphy to be established and thus to collect seasonally adjusted subsamples from the core in the field. The mean annual accumulation rate decreases from about 440mm water equivalent at the western sites T9 and T13 to about 250mm at the central positions T41 and Crête. Most of the prominent inter-annual changes of the surface mass balance appear to be well preserved over the area investigated. A comparison of the accumulation rates of the last decades with earlier measurements along the same Greenland flow line shows no significant change in accumulation rates during the last forty years. Further, there is no significant evidence for a pronounced increase in the Greenland surface mass balance as suggested by satellite altimetry.

  2. The Significance of Australian Vocational Education Institutions in Opening Access to Higher Education

    ERIC Educational Resources Information Center

    Moodie, Gavin; Wheelahan, Leesa

    2009-01-01

    Vocational education provides an educational but not a social ladder of opportunity to Australian higher education. The five dual-sector universities with significant enrolments in both vocational and higher education admit about twice the proportion of students transferring from vocational education as other universities. However, since the…

  3. The significance of Rzehakia shell accumulations in the Lower Miocene of the Central Paratethys

    NASA Astrophysics Data System (ADS)

    Mandic, O.

    2009-04-01

    Rzehakia is a bivalve genus endemic for the Paratethys. Rzehakia bearing deposits can be traced from the Western Alpine Foredeep of the Swabian Alb (Kirchberg Formation; Upper Marine Molasse) over the Eastern Alpine and Carpathian Foredeep (upper Ottnangian of the Central Paratethys) up to Georgia in the East (Kotsakhurian of the Eastern Paratethys). Their deposition coincides with the tectonic inversion and the final onset of lacustrine and terrestrial environment in the Alpine Foredeep. Furthermore they are time equivalents of the initial subsidence and rifting of the Pannonian Basin System. Rzehakia shell accumulations mark the most prominent Lower Miocene restriction and endemic event in the Central Paratethys. They represent the major regression in the late Ottnangian before the last Lower Miocene marine pulse of the Karpatian. The Rzehakiidae representatives are accompanied in corresponding deposits by endemic Lymnocardiidae bivalves and different lacustrine to marginal marine gastropod species. Their faunal distribution pattern provides strong evidence for the well established paleogeographic connection throughout the Paratethys during late Ottnangian. In the Central Paratethys, however, conspicuous West-East faunal gradient is present with the western assemblage characterized through Rzehakia guembeli and Limnopagetia bavarica and the eastern assemblage bearing Rzehakia socialis, Limnopagetia moravica and Limnopagetia ammoni. Mandic & Ćorić (2007: Eine neue Molluskenfauna aus dem oberen Ottnangium von Rassing (NÖ) - taxonomische, biostratigraphische, paläoökologische und paläobiogeographische Auswertung. - Jahrbuch der Geologischen Bundesanstalt, 147: 387-398) located currently their transitional contact in the Lower Austrian Eastern Alpine Foredeep, showing co-occurrence of species from both paleobiogeographic entities. The study is part of the Austrian FWF Project P18519-B17.

  4. Phytochelatin synthesis is essential for the detoxification of excess zinc and contributes significantly to the accumulation of zinc.

    PubMed

    Tennstedt, Pierre; Peisker, Daniel; Böttcher, Christoph; Trampczynska, Aleksandra; Clemens, Stephan

    2009-02-01

    The synthesis of phytochelatins (PCs) is essential for the detoxification of nonessential metals and metalloids such as cadmium and arsenic in plants and a variety of other organisms. To our knowledge, no direct evidence for a role of PCs in essential metal homeostasis has been reported to date. Prompted by observations in Schizosaccharomyces pombe and Saccharomyces cerevisiae indicating a contribution of PC synthase expression to Zn2+ sequestration, we investigated a known PC-deficient Arabidopsis (Arabidopsis thaliana) mutant, cad1-3, and a newly isolated second strong allele, cad1-6, with respect to zinc (Zn) homeostasis. We found that in a medium with low cation content PC-deficient mutants show pronounced Zn2+ hypersensitivity. This phenotype is of comparable strength to the well-documented Cd2+ hypersensitivity of cad1 mutants. PC deficiency also results in significant reduction in root Zn accumulation. To be able to sensitively measure PC accumulation, we established an assay using capillary liquid chromatography coupled to electrospray ionization quadrupole time-of-flight mass spectrometry of derivatized extracts. Plants grown under control conditions consistently showed PC2 accumulation. Analysis of plants treated with same-effect concentrations revealed that Zn2+-elicited PC2 accumulation in roots reached about 30% of the level of Cd2+-elicited PC2 accumulation. We conclude from these data that PC formation is essential for Zn2+ tolerance and provides driving force for the accumulation of Zn. This function might also help explain the mysterious occurrence of PC synthase genes throughout the plant kingdom and in a wide range of other organisms.

  5. The Inception of the Meaning and Significance of Endowment in American Higher Education, 1890-1930

    ERIC Educational Resources Information Center

    Kimball, Bruce A.; Johnson, Benjamin Ashby

    2012-01-01

    Background/Context: Endowments of institutions of higher education in the United States have attracted widespread attention in recent decades due to their meteoric rise in value and their precipitous decline during the recent recession. But there has been little research on the beginnings of the significant interest in and importance of…

  6. Biological significance of ( sup 14 C)phenol accumulation in different organs of a murrel, Channa punctatus, and the common carp, Cyprinus carpio

    SciTech Connect

    Mukherjee, D.; Bhattacharya, S.; Kumar, V.; Moitra, J. )

    1990-09-01

    Phenol, a ubiquitous component of industrial effluents, is a common pollutant of water resources and a serious threat to fish. The present work demonstrates that a significant amount of phenol is retained by various tissues of the common carp, Cyprinus carpio, and the snake-headed murrel, Channa punctatus. The rate of ({sup 14}C)phenol accumulation was higher carp than in the murrel. It is suggested that retention of phenol in the brain and ovary may seriously affect the reproductive potential of the fish.

  7. PCOS women show significantly higher homocysteine level, independent to glucose and E2 level

    PubMed Central

    Eskandari, Zahra; Sadrkhanlou, Rajab-Ali; Nejati, Vahid; Tizro, Gholamreza

    2016-01-01

    Background: It is reasonable to think that some biochemical characteristics of follicular fluid (FF) surrounding the oocyte may play a critical role in determining the quality of oocyte and the subsequent potential needed to achieve fertilization and embryo development. Objective: This study was carried out to evaluate the levels of FF homocysteine (Hcy) in IVF candidate polycystic ovary syndrome (PCOS) women and any relationships with FF glucose and estradiol (E2) levels. Materials and Methods: In this case control study which was performed in Dr. Tizro Day Care and IVF Center 70 infertile patients were enrolled in two groups: comprising 35 PCOS and 35 non PCOS women. Long protocol was performed for all patients. FF Hcy, glucose and E2 levels were analyzed at the time of oocyte retrieval. Results: It was observed that FF Hcy level was significantly higher in PCOS patients compared with non PCOSs (p<0.01). Observations demonstrated that in PCOS group, the Hcy level increased independent to E2, glucose levels, BMI and age, while the PCOS group showed significantly higher BMI compared with non-PCOS group (p=0.03). However, no significant differences were revealed between groups for FF glucose and E2 levels. Conclusion: Present data showed that although FF glucose and E2 levels were constant in PCOS and non PCOS patients, but the FF Hcy levels in PCOS were significantly increased (p=0.01). PMID:27679823

  8. PCOS women show significantly higher homocysteine level, independent to glucose and E2 level

    PubMed Central

    Eskandari, Zahra; Sadrkhanlou, Rajab-Ali; Nejati, Vahid; Tizro, Gholamreza

    2016-01-01

    Background: It is reasonable to think that some biochemical characteristics of follicular fluid (FF) surrounding the oocyte may play a critical role in determining the quality of oocyte and the subsequent potential needed to achieve fertilization and embryo development. Objective: This study was carried out to evaluate the levels of FF homocysteine (Hcy) in IVF candidate polycystic ovary syndrome (PCOS) women and any relationships with FF glucose and estradiol (E2) levels. Materials and Methods: In this case control study which was performed in Dr. Tizro Day Care and IVF Center 70 infertile patients were enrolled in two groups: comprising 35 PCOS and 35 non PCOS women. Long protocol was performed for all patients. FF Hcy, glucose and E2 levels were analyzed at the time of oocyte retrieval. Results: It was observed that FF Hcy level was significantly higher in PCOS patients compared with non PCOSs (p<0.01). Observations demonstrated that in PCOS group, the Hcy level increased independent to E2, glucose levels, BMI and age, while the PCOS group showed significantly higher BMI compared with non-PCOS group (p=0.03). However, no significant differences were revealed between groups for FF glucose and E2 levels. Conclusion: Present data showed that although FF glucose and E2 levels were constant in PCOS and non PCOS patients, but the FF Hcy levels in PCOS were significantly increased (p=0.01).

  9. Risk of abnormal triple screen for Down syndrome is significantly higher in patients with female fetuses.

    PubMed

    Spong, C Y; Ghidini, A; Stanley-Christian, H; Meck, J M; Seydel, F D; Pezzullo, J C

    1999-04-01

    Previous studies have shown that mid-trimester maternal serum alpha-fetoprotein (AFP) levels are significantly higher and human chorionic gonadotrophin (hCG) levels significantly lower in women with male compared with female fetuses. We have evaluated whether triple-screen criteria are more likely to identify women with female fetuses as at risk for Down syndrome. From the Georgetown University genetics database we obtained the absolute values and corresponding multiples of the median (MoM) for AFP, hCG and unconjugated oestriol (uE3) in singleton gestations for the period database November 1992 July 1996. A Down syndrome risk of 1/270 or greater at mid-trimester was considered as high risk. A total of 977 patients with triple screen and outcome information were identified, including 502 female and 475 male fetuses. Patients with female fetuses were significantly more likely to have lower serum AFP (p=0.003) and a positive triple screen for Down syndrome (72 (14 per cent) versus 45 (9 per cent), p<0.02) than those with male fetuses. The gestational age at triple screen, maternal serum hCG and uE3, race and diabetes were not significantly different between the two groups. Since Down syndrome is less common in female than male fetuses, and the rates of female and male Down syndrome fetuses detected by triple screen and subsequent amniocentesis are not significantly different, the excess of positive mid-trimester maternal serum triple screen in women with female fetuses is likely due to false-positive results. PMID:10327139

  10. Docosahexaenoic acid content is significantly higher in ghrita prepared by traditional Ayurvedic method

    PubMed Central

    Joshi, Kalpana S.

    2014-01-01

    Background: Ghee (clarified butter) also known as ghrita, has been utilized for thousands of years in Ayurveda. Ghee is mostly prepared by traditional method in Indian households or by direct cream method at industry level. Ayurvedic classics mention that ghrita made from cow milk is superior. However, there is no scientific comparison available on preparation methods and essential fatty acids content of ghrita. Objective: To investigate fatty acid composition of ghrita prepared by traditional/Ayurvedic method and commercial method (direct cream method). Materials and Methods: Fatty Acid Methyl Esters (FAME) extracted from ghrita samples were analysed on Gas Chromatography (GC) Shimadzu B using capillary column BPX70 (0.32 mm*60 m, ID of 0.25 mm). The fatty acids in the samples were identified by comparing peaks with the external standard 68A (Nu-Chek-Prep, Inc.USA). Significant differences between the experimental groups were assessed by analysis of variance. Results: Distribution of fatty acids was compared in ghrita samples prepared by traditional method and direct cream method which is commercially used. Saturated fatty acids were predominant in both the groups. Mono unsaturated fatty acids and poly unsaturated fatty acids were in the range of 17-18% and 3-6% respectively. DHA content was significantly higher in ghee prepared by traditional method using curd starter fermentation. Conclusion: The findings suggested that ghrita prepared by traditional ayurvedic methods contains higher amount of DHA; Omega-3 long-chain polyunsaturated fatty acids, which is a major component of retinal and brain tissues and remains important in prevention of various diseases. PMID:24948858

  11. Significantly Higher Prevalence Rate of Asthma and Bipolar Disorder Co-Morbidity

    PubMed Central

    Wu, Ming-Kung; Wang, Hung-Yu; Chen, Yen-Wen; Lin, Pao-Yen; Wu, Ching-Kuan; Tseng, Ping-Tao

    2016-01-01

    Abstract Asthma and bipolar disorder (BD) are 2 distinct diseases that share similar pathophysiology. This study aimed to determine their relationship thorough a meta-analysis of articles on their comorbidity rate. The aim of the study is to examine the overall prevalence rate of BD in asthmatic patients and of asthma in BD patients compared to healthy controls. Electronic research of PubMed and ClinicalTrials.gov was performed. Articles discussing the prevalence rate of BD in patients with/without asthma and the prevalence rate of asthma in those with/without BD, as well as clinical trials in humans and case-controlled trials or cohort studies, were all included. Case reports or series and nonclinical trials were excluded. Through a random-effects model, a meta-analysis of the results of 4 studies comparing the prevalence rate of BD in patients with/without asthma, and in 6 studies comparing the prevalence rate of asthma in subjects with/without BD were performed. There were significantly higher prevalence rates of BD in asthmatic patients than in healthy controls (P < 0.001) and of asthma in BD patients than in healthy controls (P < 0.001). Only the patient's mean age significantly modulated the odds ratio of the prevalence rate of asthma in BD patients (slope = 0.015, P < 0.001). Only 10 studies were included and most were cross-sectional studies. The possible confounding effect of medication on BD or asthma onset was not investigated. Any possible etiology of the comorbidity was also not determined. This meta-analysis highlights the importance of the significantly high comorbid rate of BD and asthma, and the positive association with age. Special attention must be given to the comorbidity of asthma and BD, especially in older patients. PMID:27043688

  12. Significantly Improving Regional Seismic Amplitude Tomography at Higher Frequencies by Determining S -Wave Bandwidth

    DOE PAGES

    Fisk, Mark D.; Pasyanos, Michael E.

    2016-05-03

    Characterizing regional seismic signals continues to be a difficult problem due to their variability. Calibration of these signals is very important to many aspects of monitoring underground nuclear explosions, including detecting seismic signals, discriminating explosions from earthquakes, and reliably estimating magnitude and yield. Amplitude tomography, which simultaneously inverts for source, propagation, and site effects, is a leading method of calibrating these signals. A major issue in amplitude tomography is the data quality of the input amplitude measurements. Pre-event and prephase signal-to-noise ratio (SNR) tests are typically used but can frequently include bad signals and exclude good signals. The deficiencies ofmore » SNR criteria, which are demonstrated here, lead to large calibration errors. To ameliorate these issues, we introduce a semi-automated approach to assess the bandwidth of a spectrum where it behaves physically. We determine the maximum frequency (denoted as Fmax) where it deviates from this behavior due to inflections at which noise or spurious signals start to bias the spectra away from the expected decay. We compare two amplitude tomography runs using the SNR and new Fmax criteria and show significant improvements to the stability and accuracy of the tomography output for frequency bands higher than 2 Hz by using our assessments of valid S-wave bandwidth. We compare Q estimates, P/S residuals, and some detailed results to explain the improvements. Lastly, for frequency bands higher than 4 Hz, needed for effective P/S discrimination of explosions from earthquakes, the new bandwidth criteria sufficiently fix the instabilities and errors so that the residuals and calibration terms are useful for application.« less

  13. Higher resolution stimulus facilitates depth perception: MT+ plays a significant role in monocular depth perception.

    PubMed

    Tsushima, Yoshiaki; Komine, Kazuteru; Sawahata, Yasuhito; Hiruma, Nobuyuki

    2014-01-01

    Today, we human beings are facing with high-quality virtual world of a completely new nature. For example, we have a digital display consisting of a high enough resolution that we cannot distinguish from the real world. However, little is known how such high-quality representation contributes to the sense of realness, especially to depth perception. What is the neural mechanism of processing such fine but virtual representation? Here, we psychophysically and physiologically examined the relationship between stimulus resolution and depth perception, with using luminance-contrast (shading) as a monocular depth cue. As a result, we found that a higher resolution stimulus facilitates depth perception even when the stimulus resolution difference is undetectable. This finding is against the traditional cognitive hierarchy of visual information processing that visual input is processed continuously in a bottom-up cascade of cortical regions that analyze increasingly complex information such as depth information. In addition, functional magnetic resonance imaging (fMRI) results reveal that the human middle temporal (MT+) plays a significant role in monocular depth perception. These results might provide us with not only the new insight of our neural mechanism of depth perception but also the future progress of our neural system accompanied by state-of- the-art technologies. PMID:25327168

  14. Magnitude and significance of the higher-order reduced density matrix cumulants

    NASA Astrophysics Data System (ADS)

    Herbert, John M.

    Using full configuration interaction wave functions for Be and LiH, in both minimal and extended basis sets, we examine the absolute magnitude and energetic significance of various contributions to the three-electron reduced density matrix (3-RDM) and its connected (size-consistent) component, the 3-RDM cumulant (3-RDMC). Minimal basis sets are shown to suppress the magnitude of the 3-RDMC in an artificial manner, whereas in extended basis sets, 3-RDMC matrix elements are often comparable in magnitude to the corresponding 3-RDM elements, even in cases where this result is not required by spin angular momentum coupling. Formal considerations suggest that these observations should generalize to higher-order p-RDMs and p-RDMCs (p > 3). This result is discussed within the context of electronic structure methods based on the contracted Schrödinger equation (CSE), as solution of the CSE relies on 3- and 4-RDM ?reconstruction functionals? that neglect the 3-RDMC, the 4-RDMC, or both. Although the 3-RDMC is responsible for at most 0.2% of the total electronic energy in Be and LiH, it accounts for up to 70% of the correlation energy, raising questions regarding whether (and how) the CSE can offer a useful computational methodology.

  15. Higher resolution stimulus facilitates depth perception: MT+ plays a significant role in monocular depth perception.

    PubMed

    Tsushima, Yoshiaki; Komine, Kazuteru; Sawahata, Yasuhito; Hiruma, Nobuyuki

    2014-10-20

    Today, we human beings are facing with high-quality virtual world of a completely new nature. For example, we have a digital display consisting of a high enough resolution that we cannot distinguish from the real world. However, little is known how such high-quality representation contributes to the sense of realness, especially to depth perception. What is the neural mechanism of processing such fine but virtual representation? Here, we psychophysically and physiologically examined the relationship between stimulus resolution and depth perception, with using luminance-contrast (shading) as a monocular depth cue. As a result, we found that a higher resolution stimulus facilitates depth perception even when the stimulus resolution difference is undetectable. This finding is against the traditional cognitive hierarchy of visual information processing that visual input is processed continuously in a bottom-up cascade of cortical regions that analyze increasingly complex information such as depth information. In addition, functional magnetic resonance imaging (fMRI) results reveal that the human middle temporal (MT+) plays a significant role in monocular depth perception. These results might provide us with not only the new insight of our neural mechanism of depth perception but also the future progress of our neural system accompanied by state-of- the-art technologies.

  16. Higher Education Financing in the Fifty States: Significance for the 'Adams' States.

    ERIC Educational Resources Information Center

    Budig, Jeanne E.; Khan, Anwar

    Findings of a study on higher education financing in the states are summarized with specific reference for the states covered by the 1977 Adams versus Richardson decision. The study, "Higher Education Financing in the Fifty States: Interstate Comparisons" (Marilyn McCoy, D. Kent Halstead), was jointly issued by the National Center for Higher…

  17. Significant accumulation of persistent organic pollutants and dysregulation in multiple DNA damage repair pathways in the electronic-waste-exposed populations

    SciTech Connect

    He, Xiaobo; Jing, Yaqing; Wang, Jianhai; Li, Keqiu; Yang, Qiaoyun; Zhao, Yuxia; Li, Ran; Ge, Jie; Qiu, Xinghua; Li, Guang

    2015-02-15

    Electronic waste (e-waste) has created a worldwide environmental and health problem, by generating a diverse group of hazardous compounds such as persistent organic pollutants (POPs). Our previous studies demonstrated that populations from e-waste exposed region have a significantly higher level of chromosomal aberrancy and incidence of DNA damage. In this study, we further demonstrated that various POPs persisted at a significantly higher concentration in the exposed group than those in the unexposed group. The level of reactive oxygen species and micronucleus rate were also significantly elevated in the exposed group. RNA sequencing analysis revealed 31 genes in DNA damage responses and repair pathways that were differentially expressed between the two groups (Log 2 ratio >1 or <−1). Our data demonstrated that both females and males of the exposed group have activated a series of DNA damage response genes; however many important DNA repair pathways have been dysregulated. Expressions of NEIL1/3 and RPA3, which are critical in initiating base pair and nucleotide excision repairs respectively, have been downregulated in both females and males of the exposed group. In contrast, expression of RNF8, an E3 ligase involved in an error prone non-homologous end joining repair for DNA double strand break, was upregulated in both genders of the exposed group. The other genes appeared to be differentially expressed only when the males or females of the two groups were compared respectively. Importantly, the expression of cell cycle regulatory gene CDC25A that has been implicated in multiple kinds of malignant transformation was significantly upregulated among the exposed males while downregulated among the exposed females. In conclusion, our studies have demonstrated significant correlations between e-waste disposing and POPs accumulation, DNA lesions and dysregulation of multiple DNA damage repair mechanisms in the residents of the e-waste exposed region. - Highlights:

  18. The Significance of Blackstone's Understanding of Sovereign Immunity for America's Public Institutions of Higher Education.

    ERIC Educational Resources Information Center

    Snow, Brian A.; Thro, William E.

    2001-01-01

    Asserts that from the perspective of America's public institutions of higher education, Blackstone's greatest legacy is his understanding of sovereign immunity. Explores the similarities between Blackstone's understanding of sovereign immunity and the current jurisprudence of the U.S. Supreme Court. (EV)

  19. Significance of neuro-cardiac control mechanisms governed by higher regions of the brain.

    PubMed

    Taggart, Peter; Critchley, Hugo; van Duijvendoden, Stefan; Lambiase, Pier D

    2016-08-01

    Advances in investigative techniques have led to an increasing awareness and understanding of the role of central neural control in the autonomic nervous system regulation of the heart. Substantial evidence exists for a role of the higher centres in neuro-cardiac control including the effect of focal brain stimulation and acute brain lesions on cardiac electrophysiology, blood pressure, contractile function and the development of arrhythmias. Mental stress and strong emotions have long been associated with sudden cardiac death. There is an emerging literature relating the gene-environment interactions in determining the neural patterning responsible for the stress response itself. The role of the higher brain centres in determining myocardial behaviour has become accessible through the utilisation of optogenetic techniques to modulate activity in specific brainstem nuclei, enabling the dissection of specific vagal and sympathetic inputs on cardiac electrophysiology and arrhythmogenesis. Central cardiac control mechanisms are modulated by afferent signals from the heart. Ascending interoceptive pathways from heart to several forebrain regions influence the behavioural response and autonomic output to the heart. These processes are expressed as control loops at multiple levels of the neuraxis and are assumed to converge in part at the level of the baroreflex to shape the efferent drive to the heart and vasculature. PMID:27595200

  20. Tacrolimus dose requirement in renal transplant recipients is significantly higher when used in combination with corticosteroids

    PubMed Central

    Hesselink, Dennis A; Ngyuen, Hien; Wabbijn, Marike; Gregoor, Peter J H Smak; Steyerberg, Ewout W; van Riemsdijk, Iza C; Weimar, Willem; van Gelder, Teun

    2003-01-01

    Aims To evaluate the effect of corticosteroids on tacrolimus pharmacokinetics. Methods In a randomized trial, kidney transplant recipients were treated with tacrolimus and mycophenolate mofetil with either daclizumab (n = 31) or 3 months of prednisone (n = 34). Tacrolimus dose-adjusted predose concentrations (C0) at month 1–6 were compared between both groups and within the corticosteroid group before and after prednisone withdrawal. Results At month 1 the tacrolimus dose-adjusted C0 in the corticosteroid group was 83 ± 8 vs 119 ± 17 ng ml−1 mg−1 kg−1 in the daclizumab group. The tacrolimus dose-adjusted C0 within the corticosteroid group at month 1 and 2 was 42% and 29% lower compared with month 4 (P < 0.001). Conclusions A higher tacrolimus dose is required to reach target concentrations when used in combination with corticosteroids. PMID:12919182

  1. Spatially resolved flux measurements of NOx from London suggest significantly higher emissions than predicted by inventories.

    PubMed

    Vaughan, Adam R; Lee, James D; Misztal, Pawel K; Metzger, Stefan; Shaw, Marvin D; Lewis, Alastair C; Purvis, Ruth M; Carslaw, David C; Goldstein, Allen H; Hewitt, C Nicholas; Davison, Brian; Beevers, Sean D; Karl, Thomas G

    2016-07-18

    To date, direct validation of city-wide emissions inventories for air pollutants has been difficult or impossible. However, recent technological innovations now allow direct measurement of pollutant fluxes from cities, for comparison with emissions inventories, which are themselves commonly used for prediction of current and future air quality and to help guide abatement strategies. Fluxes of NOx were measured using the eddy-covariance technique from an aircraft flying at low altitude over London. The highest fluxes were observed over central London, with lower fluxes measured in suburban areas. A footprint model was used to estimate the spatial area from which the measured emissions occurred. This allowed comparison of the flux measurements to the UK's National Atmospheric Emissions Inventory (NAEI) for NOx, with scaling factors used to account for the actual time of day, day of week and month of year of the measurement. The comparison suggests significant underestimation of NOx emissions in London by the NAEI, mainly due to its under-representation of real world road traffic emissions. A comparison was also carried out with an enhanced version of the inventory using real world driving emission factors and road measurement data taken from the London Atmospheric Emissions Inventory (LAEI). The measurement to inventory agreement was substantially improved using the enhanced version, showing the importance of fully accounting for road traffic, which is the dominant NOx emission source in London. In central London there was still an underestimation by the inventory of 30-40% compared with flux measurements, suggesting significant improvements are still required in the NOx emissions inventory.

  2. Spatially resolved flux measurements of NOx from London suggest significantly higher emissions than predicted by inventories.

    PubMed

    Vaughan, Adam R; Lee, James D; Misztal, Pawel K; Metzger, Stefan; Shaw, Marvin D; Lewis, Alastair C; Purvis, Ruth M; Carslaw, David C; Goldstein, Allen H; Hewitt, C Nicholas; Davison, Brian; Beevers, Sean D; Karl, Thomas G

    2016-07-18

    To date, direct validation of city-wide emissions inventories for air pollutants has been difficult or impossible. However, recent technological innovations now allow direct measurement of pollutant fluxes from cities, for comparison with emissions inventories, which are themselves commonly used for prediction of current and future air quality and to help guide abatement strategies. Fluxes of NOx were measured using the eddy-covariance technique from an aircraft flying at low altitude over London. The highest fluxes were observed over central London, with lower fluxes measured in suburban areas. A footprint model was used to estimate the spatial area from which the measured emissions occurred. This allowed comparison of the flux measurements to the UK's National Atmospheric Emissions Inventory (NAEI) for NOx, with scaling factors used to account for the actual time of day, day of week and month of year of the measurement. The comparison suggests significant underestimation of NOx emissions in London by the NAEI, mainly due to its under-representation of real world road traffic emissions. A comparison was also carried out with an enhanced version of the inventory using real world driving emission factors and road measurement data taken from the London Atmospheric Emissions Inventory (LAEI). The measurement to inventory agreement was substantially improved using the enhanced version, showing the importance of fully accounting for road traffic, which is the dominant NOx emission source in London. In central London there was still an underestimation by the inventory of 30-40% compared with flux measurements, suggesting significant improvements are still required in the NOx emissions inventory. PMID:27098421

  3. In vivo speciation studies and antioxidant properties of bromine in Laminaria digitata reinforce the significance of iodine accumulation for kelps.

    PubMed

    Küpper, Frithjof C; Carpenter, Lucy J; Leblanc, Catherine; Toyama, Chiaki; Uchida, Yuka; Maskrey, Benjamin H; Robinson, Joanne; Verhaeghe, Elodie F; Malin, Gill; Luther, George W; Kroneck, Peter M H; Kloareg, Bernard; Meyer-Klaucke, Wolfram; Muramatsu, Yasuyuki; Megson, Ian L; Potin, Philippe; Feiters, Martin C

    2013-07-01

    The metabolism of bromine in marine brown algae remains poorly understood. This contrasts with the recent finding that the accumulation of iodide in the brown alga Laminaria serves the provision of an inorganic antioxidant - the first case documented from a living system. The aim of this study was to use an interdisciplinary array of techniques to study the chemical speciation, transformation, and function of bromine in Laminaria and to investigate the link between bromine and iodine metabolism, in particular in the antioxidant context. First, bromine and iodine levels in different Laminaria tissues were compared by inductively coupled plasma MS. Using in vivo X-ray absorption spectroscopy, it was found that, similarly to iodine, bromine is predominantly present in this alga in the form of bromide, albeit at lower concentrations, and that it shows similar behaviour upon oxidative stress. However, from a thermodynamic and kinetic standpoint, supported by in vitro and reconstituted in vivo assays, bromide is less suitable than iodide as an antioxidant against most reactive oxygen species except superoxide, possibly explaining why kelps prefer to accumulate iodide. This constitutes the first-ever study exploring the potential antioxidant function of bromide in a living system and other potential physiological roles. Given the tissue-specific differences observed in the content and speciation of bromine, it is concluded that the bromide uptake mechanism is different from the vanadium iodoperoxidase-mediated uptake of iodide in L. digitata and that its function is likely to be complementary to the iodide antioxidant system for detoxifying superoxide.

  4. In vivo speciation studies and antioxidant properties of bromine in Laminaria digitata reinforce the significance of iodine accumulation for kelps

    PubMed Central

    Küpper, Frithjof C.; Carpenter, Lucy J.; Leblanc, Catherine; Toyama, Chiaki; Uchida, Yuka; Maskrey, Benjamin H.; Robinson, Joanne; Verhaeghe, Elodie F.; Malin, Gill; Luther, George W.; Kroneck, Peter M. H.; Kloareg, Bernard; Meyer-Klaucke, Wolfram; Muramatsu, Yasuyuki; Megson, Ian L.; Potin, Philippe; Feiters, Martin C.

    2013-01-01

    The metabolism of bromine in marine brown algae remains poorly understood. This contrasts with the recent finding that the accumulation of iodide in the brown alga Laminaria serves the provision of an inorganic antioxidant – the first case documented from a living system. The aim of this study was to use an interdisciplinary array of techniques to study the chemical speciation, transformation, and function of bromine in Laminaria and to investigate the link between bromine and iodine metabolism, in particular in the antioxidant context. First, bromine and iodine levels in different Laminaria tissues were compared by inductively coupled plasma MS. Using in vivo X-ray absorption spectroscopy, it was found that, similarly to iodine, bromine is predominantly present in this alga in the form of bromide, albeit at lower concentrations, and that it shows similar behaviour upon oxidative stress. However, from a thermodynamic and kinetic standpoint, supported by in vitro and reconstituted in vivo assays, bromide is less suitable than iodide as an antioxidant against most reactive oxygen species except superoxide, possibly explaining why kelps prefer to accumulate iodide. This constitutes the first-ever study exploring the potential antioxidant function of bromide in a living system and other potential physiological roles. Given the tissue-specific differences observed in the content and speciation of bromine, it is concluded that the bromide uptake mechanism is different from the vanadium iodoperoxidase-mediated uptake of iodide in L. digitata and that its function is likely to be complementary to the iodide antioxidant system for detoxifying superoxide. PMID:23606364

  5. 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

  6. 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.

  7. [Endarterectomy more favourable than stenting in symptomatic significant carotid stenosis: higher risk of ischaemic stroke or death following stenting].

    PubMed

    Meerwaldt, Robbert; Beuk, Roland J; Huisman, Ad B; Manschot, Sanne M; Zeebregts, Clark J; Geelkerken, Robert H

    2011-01-01

    Carotid endarterectomy (CEA) has proven its value in the treatment of patients with recent significant carotid artery stenosis. Percutaneous transluminal angioplasty with carotid artery stenting ('stenting' in short) is an alternative to CEA. The results of stenting and CEA in patients with symptomatic significant carotid artery stenosis were evaluated in 9 prospective randomized controlled trials and 11 meta-analyses. Almost all of these trials failed to show superiority of stenting to CEA. According to the 4 largest and most recent studies in this field the risk of a stroke or death within 30 days after the intervention is considerably higher following stenting than following CEA. In the long run the results of stenting and CEA seem to be comparable. CEA remains the gold standard in treatment of significant carotid artery stenosis, in particular in patients older than 70. PMID:21329537

  8. [Endarterectomy more favourable than stenting in symptomatic significant carotid stenosis: higher risk of ischaemic stroke or death following stenting].

    PubMed

    Meerwaldt, Robbert; Beuk, Roland J; Huisman, Ad B; Manschot, Sanne M; Zeebregts, Clark J; Geelkerken, Robert H

    2011-01-01

    Carotid endarterectomy (CEA) has proven its value in the treatment of patients with recent significant carotid artery stenosis. Percutaneous transluminal angioplasty with carotid artery stenting ('stenting' in short) is an alternative to CEA. The results of stenting and CEA in patients with symptomatic significant carotid artery stenosis were evaluated in 9 prospective randomized controlled trials and 11 meta-analyses. Almost all of these trials failed to show superiority of stenting to CEA. According to the 4 largest and most recent studies in this field the risk of a stroke or death within 30 days after the intervention is considerably higher following stenting than following CEA. In the long run the results of stenting and CEA seem to be comparable. CEA remains the gold standard in treatment of significant carotid artery stenosis, in particular in patients older than 70.

  9. Reoxygenation of Asphyxiated Newborn Piglets: Administration of 100% Oxygen Causes Significantly Higher Apoptosis in Cortical Neurons, as Compared to 21%

    PubMed Central

    Faa, G.; Fanos, V.; Fanni, D.; Gerosa, C.; Faa, A.; Fraschini, M.; Pais, M. E.; Di Felice, E.; Papalois, A.; Varsami, M.; Xanthos, T.; Iacovidou, N.

    2014-01-01

    Objective. Evaluation of neuronal changes in an animal experimental model of normocapnic hypoxia- reoxygenation. Materials and Methods. Fifty male piglets were the study subjects; normocapnic hypoxia was induced in 40 piglets and ten were sham-operated (controls). When bradycardia and/or severe hypotension occurred, reoxygenation was initiated. Animals were allocated in 4 groups according to the oxygen concentration, they were resuscitated with 18%, 21%, 40%, and 100% O2. Persisting asystole despite 10 minutes of cardiopulmonary resuscitation and return of spontaneous circulation were the endpoints of the experiment. Surviving animals were euthanized and brain cortex samples were collected, hematoxylin and eosin-stained, and examined for apoptotic bodies observing 10 consecutive high power fields. Results. Histological examination of the control group did not show any pathological change. On the contrary, apoptosis of neurons was found in 87.5% of treated animals. When specimens were examined according to the oxygen concentration used for resuscitation, we found marked intergroup variability; a higher percentage of apoptotic neurons was observed in piglets of group 4 (100% oxygen) compared to the others (P = 0.001). Conclusions. This preliminary data shows that normocapnic hypoxia and reoxygenation in Landrace/Large White piglets resulted in significant histological changes in the brain cortex. The degree of pathological changes in cortical neurons was significantly associated with the oxygen concentration used for reoxygenation, with a higher percentage of apoptotic neurons being observed in piglets reoxygenated with 100% compared to 18% O2 and to 21% O2. PMID:24783208

  10. 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

  11. 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.

  12. 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.

  13. Significance of Trends on Enrolment, Budget and Actual Expenditure in the Examination of Higher Education Financing in Tanzania

    ERIC Educational Resources Information Center

    Memba, Albert Zephaniah; Feng, Zhao Jun

    2016-01-01

    Financing of higher education in Tanzania is considered a crucial factor in realizing the country's development vision. It is for these reasons that Tanzania has been financing its higher education since its inception. Diminishing resource capacity and competing interests for government finance plunged the higher education into financial doldrums.…

  14. 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

  15. Tribes and Territories in the 21st Century: Rethinking the Significance of Disciplines in Higher Education. International Studies in Higher Education

    ERIC Educational Resources Information Center

    Trowler, Paul, Ed.; Saunders, Murray, Ed.; Bamber, Veronica, Ed.

    2012-01-01

    The "tribes and territories" metaphor for the cultures of academic disciplines and their roots in different knowledge characteristics has been used by those interested in university life and work since the early 1990s. This book draws together research, data and theory to show how higher education has gone through major change since then and how…

  16. Judgments of learning are significantly higher following feedback on relatively good versus relatively poor trials despite no actual learning differences.

    PubMed

    Carter, Michael J; Smith, Victoria; Ste-Marie, Diane M

    2016-02-01

    Studies have consistently shown that prospective metacognitive judgments of learning are often inaccurate because humans mistakenly interpret current performance levels as valid indices of learning. These metacognitive discrepancies are strongly related to conditions of practice. Here, we examined how the type of feedback (after good versus poor trials) received during practice and awareness (aware versus unaware) of this manipulation affected judgments of learning and actual learning. After each six-trial block, participants received feedback on their three best trials or three worst trials and half of the participants were made explicitly aware of the type of feedback they received while the other half were unaware. Judgments of learning were made at the end of each six-trial block and before the 24-h retention test. Results indicated no motor performance differences between groups in practice or retention; however, receiving feedback on relatively good compared to relatively poor trials resulted in significantly higher judgments of learning in practice and retention, irrespective of awareness. These results suggest that KR on relatively good versus relatively poor trials can have dissociable effects on judgments of learning in the absence of actual learning differences, even when participants are made aware of their feedback manipulation.

  17. How Different Are Higher Education Institutions in the UK, US and Australia? The Significance of Government Involvement

    ERIC Educational Resources Information Center

    Moodie, Gavin

    2015-01-01

    Governments in the UK and many other countries have long sought to promote the diversity of their higher education institutions. However, diversity is hard to define, harder to measure and even more difficult to compare between countries. Most empirical analyses of the diversity of higher education systems use categorical variables, which shape…

  18. Higher Education in the United Arab Emirates: An Analysis of the Outcomes of Significant Increases in Supply and Competition

    ERIC Educational Resources Information Center

    Wilkins, Stephen

    2010-01-01

    During the last decade, several countries across the Middle and Far East have established higher education hubs, some of which have grown rapidly by attracting foreign universities to set up international branch campuses. The United Arab Emirates (UAE) is by far the largest host of international branch campuses globally, having over 40 providers…

  19. 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.

  20. Sources of Inspiration: The role of significant persons in young people's choice of science in higher education

    NASA Astrophysics Data System (ADS)

    Sjaastad, Jørgen

    2012-07-01

    The objectives of this article were to investigate to which extent and in what ways persons influence students' choice of science, technology, engineering, and mathematics (STEM) in tertiary education, and to assess the suitability of an analytical framework for describing this influence. In total, 5,007 Norwegian STEM students completed a questionnaire including multiple-choice as well as open-ended questions about sources of inspiration for their educational choice. Using the conceptualisation of significant persons suggested by Woelfel and Haller, the respondents' descriptions of parents and teachers are presented in order to elaborate on the different ways these significant persons influence a STEM-related educational choice. Parents engaged in STEM themselves are models, making the choice of STEM familiar, and they help youngsters define themselves through conversation and support, thus being definers. Teachers are models by displaying how STEM might bring fulfilment in someone's life and by giving pupils a positive experience with the subjects. They help young people discover their STEM abilities, thus being definers. Celebrities are reported to have minor influence on STEM-related educational choices. Both qualitative and quantitative analyses indicate that interpersonal relationships are key factors in order to inspire and motivate a choice of STEM education. Implications for recruitment issues and for research on interpersonal influence are discussed. It is suggested that initiatives to increase recruitment to STEM might be aimed at parents and other persons in interpersonal relationships with youth as a target group.

  1. Low Carbon Rice Farming Practices in the Mekong Delta Yield Significantly Higher Profits and Lower Greenhouse Gas Emissions

    NASA Astrophysics Data System (ADS)

    Rudek, J.; Van Sanh, N.; Tinh, T. K.; Tin, H. Q.; Thu Ha, T.; Pha, D. N.; Cui, T. Q.; Tin, N. H.; Son, N. N.; Thanh, H. H.; Kien, H. T.; Kritee, K.; Ahuja, R.

    2014-12-01

    The Vietnam Low-Carbon Rice Project (VLCRP) seeks to significantly reduce GHG emissions from rice cultivation, an activity responsible for more than 30% of Vietnam's overall GHG emissions, while improving livelihoods for the rice farmer community by decreasing costs and enhancing yield as well as providing supplemental farmer income through the sale of carbon credits. The Mekong Delta makes up 12% of Vietnam's land area, but produces more than 50% of the country's rice, including more than 90% of the rice for export. Rice cultivation is the main source of income for 80% of farmers in the Mekong Delta. VLCRP was launched in late 2012 in the Mekong Delta in two major rice production provinces, Kien Giang and An Giang. To date, VLCRP has completed 11 crop seasons (in Kien Giang and An Giang combined), training over 400 farmer households in applying VLCRP's package of practices (known as 1 Must - 6 Reductions) and building technical capacity to its key stakeholders and rice farmer community leaders. By adopting the 1 Must- 6 Reductions practices (including reduced seeding density, reduced fertilizer and pesticide application, and alternative wetting and drying water management), rice farmers reduce their input costs while maintaining or improving yields, and decreasing greenhouse gas emissions. The VLCRP package of practices also deliver other environmental and social co-benefits, such as reduced water pollution, improved habitat for fishery resources and reduced health risks for farmers through the reduction of agri-chemicals. VLCRP farmers use significantly less inputs (50% reduction in seed, 30% reduction in fertilizer, 40-50% reduction in water) while improving yields 5-10%, leading to an increase in profit from 10% to as high as 60% per hectare. Preliminary results indicate that the 1 Must- 6 Reductions practices have led to approximately 40-65% reductions in greenhouse gas emissions, equivalent to 4 tons of CO2e/ha/yr in An Giang and 35 tons of CO2e/ha/yr in Kien

  2. Administrators' Perceptions of Factors Related to Student Retention at Colleges with a Significant Black Student Enrollment Affiliated with the Association for Biblical Higher Education

    ERIC Educational Resources Information Center

    Wilson, Wesley B.

    2013-01-01

    This study described and explored the factors perceived as relevant to student retention by administrators at colleges and universities with significant Black student populations. The sample was 31 institutions affiliated with the Association for Biblical Higher Education (ABHE) that had Black student enrollment of 20% or more. The study sought to…

  3. Review of the Observations which have Accumulated with regard to the Significance of Diphtheria Types in the Last Four Years (1931-1935)

    PubMed Central

    Cooper, K. E.; Happold, F. C.; McLeod, J. W.; De C. Woodcock, H. E.

    1936-01-01

    , the rougher strains representing the more virulent forms in each type, receives a good deal of support from a wide survey of the accumulated observations. A considerable group of freely growing and rough-non-starch fermenting forms which are non-pathogenic would form an exception to this rule as these would be classified as rough “Mitis.” These may, however, eventually prove with further investigation to be diphtheroid strains distinct from “Mitis.” PMID:19990761

  4. 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.

  5. 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.

  6. 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

  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. 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.

  9. A puzzle form of a non-verbal intelligence test gives significantly higher performance measures in children with severe intellectual disability

    PubMed Central

    Bello, Katrina D; Goharpey, Nahal; Crewther, Sheila G; Crewther, David P

    2008-01-01

    Background Assessment of 'potential intellectual ability' of children with severe intellectual disability (ID) is limited, as current tests designed for normal children do not maintain their interest. Thus a manual puzzle version of the Raven's Coloured Progressive Matrices (RCPM) was devised to appeal to the attentional and sensory preferences and language limitations of children with ID. It was hypothesized that performance on the book and manual puzzle forms would not differ for typically developing children but that children with ID would perform better on the puzzle form. Methods The first study assessed the validity of this puzzle form of the RCPM for 76 typically developing children in a test-retest crossover design, with a 3 week interval between tests. A second study tested performance and completion rate for the puzzle form compared to the book form in a sample of 164 children with ID. Results In the first study, no significant difference was found between performance on the puzzle and book forms in typically developing children, irrespective of the order of completion. The second study demonstrated a significantly higher performance and completion rate for the puzzle form compared to the book form in the ID population. Conclusion Similar performance on book and puzzle forms of the RCPM by typically developing children suggests that both forms measure the same construct. These findings suggest that the puzzle form does not require greater cognitive ability but demands sensory-motor attention and limits distraction in children with severe ID. Thus, we suggest the puzzle form of the RCPM is a more reliable measure of the non-verbal mentation of children with severe ID than the book form. PMID:18671882

  10. SU-E-J-66: Significant Anatomical and Dosimetric Changes Observed with the Pharyngeal Constrictor During Head and Neck Radiotherapy Elicited From Daily Deformable Image Registration and Dose Accumulation

    SciTech Connect

    Kumarasiri, A; Siddiqui, F; Liu, C; Kamal, M; Fraser, C; Chetty, I; Kim, J

    2015-06-15

    Purpose: To evaluate the anatomical changes and associated dosimetric consequences to the pharyngeal constrictor (PC) that occurs during head and neck radiotherapy (H&N RT). Methods: A cohort of 13 oro-pharyngeal cancer patients, who had daily CBCT’s for localization, was retrospectively studied. On every 5th CBCT, PC was manually delineated by a radiation oncologist. The anterior-posterior PC thickness was measured at the C3 level. Delivered dose to PC was estimated by calculating daily doses on CBCT’s, and accumulating to corresponding planning CT images. For accumulation, a parameter-optimized B- spline-based deformable image registration algorithm (Elastix) was used, in conjunction with an energy-mass mapping dose transfer algorithm. Mean and maximum dose (Dmean, Dmax) to PC was determined and compared with corresponding planned quantities. Results: The mean (±standard deviation) volume increase (ΔV) and thickness increase (Δt) over the course of 35 total fractions were 54±33% (11.9±7.6 cc), and 63±39% (2.9±1.9 mm), respectively. The resultant cumulative mean dose increase from planned dose to PC (ΔDmean) was 1.4±1.3% (0.9±0.8 Gy), while the maximum dose increase (ΔDmax) was 0.0±1.6% (0.0±1.1 Gy). Patients with adaptive replanning (n=6) showed a smaller mean dose increase than those without (n=7); 0.5±0.2% (0.3±0.1 Gy) vs. 2.2±1.4% (1.4±0.9 Gy). There was a statistically significant (p<0.0001) strong correlation between ΔDmean and Δt (Pearson coefficient r=0.78), and a moderate-to-strong correlation (r=0.52) between ΔDmean and ΔV. Correlation between ΔDmean and weight loss ΔW (r=0.1), as well as ΔV and ΔW (r=0.2) were negligible. Conclusion: Patients were found to undergo considerable anatomical changes to pharyngeal constrictor during H&N RT, resulting in non-negligible dose deviations from intended dose. Results are indicative that pharyngeal constrictor thickness, measured at C3 level, is a good predictor for the dose change to

  11. 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.

  12. Stages in the Making of the Competence Approach and Its Significance to Teaching Medical Disciplines at Institutions of Higher Medical Learning

    ERIC Educational Resources Information Center

    Mayev, Igor V.; Dautova, Olga B.; Dicheva, Diana T.; Andreyev, Dmitry N.; Goncharenko, Aleksandra Yu.; Kucheryavy, Yury A.; Aleksandrova, Kseniya O.

    2014-01-01

    This article examines the preconditions and origins of the competence approach and various approaches to apprehending the essence of competencies: personal, functional, and cognitive. The authors cover the major stages in the making of the competence approach at institutions of higher medical learning.

  13. Significant Labor and Employment Law Issues in Higher Education During the Past Decade and What To Look for Now: A Union Perspective.

    ERIC Educational Resources Information Center

    Hendrickson, Rachel

    2000-01-01

    A union perspective of major issues in higher education labor law in the 1990s includes the 11th Circuit Court cases on whether Congress abrogated states' 11th Amendment immunity for suits under the Age Discrimination in Employment Act (ADEA) and under the Americans with Disabilities Act (ADA). Analyzes contract issues of protection around age…

  14. Significant Labor and Employment Law Issues in Higher Education During the Past Decade and What To Look for Now: A Management Perspective.

    ERIC Educational Resources Information Center

    Hunsicker Jr., J. Freedley

    2000-01-01

    A management perspective of major issues in higher education labor law in the 1990s addresses: sexual harassment; the Civil Rights Act of 1991; diversity on campus, elimination of mandatory retirement for faculty; development of contingent work force; and unionization of residents, interns, and graduate assistants. Predicts alternatives to…

  15. Significant Labor and Employment Law Issues in Higher Education During the Past Decade and What to Look for Now: The Perspective of an Academician.

    ERIC Educational Resources Information Center

    Bodah, Matthew M.

    2000-01-01

    An academician explores major issues in higher education labor law during the 1990s: union organizing by graduate teaching assistants, bargaining and workload issues, developments concerning grievance arbitration, and rights of individual faculty members within unions. Issues likely to arise in the next decade include alternatives to tenure,…

  16. Significance of the sexual openings and supplementary structures on the phylogeny of brachyuran crabs (Crustacea, Decapoda, Brachyura), with new nomina for higher-ranked podotreme taxa.

    PubMed

    Guinot, Danièle; Tavares, Marcos; Castro, Peter

    2013-01-01

    The patterns of complexity of the male and female sexual openings in Brachyura, which have been the source of uncertainties and conflicting opinions, are documented, together with a study of the morphologies of the coxal and sternal gonopores in both sexes, penises, spermathecae, and gonopods. The vulvae, male gonopores and penises are described among selected taxa of Eubrachyura, and their function and evolution examined in the context of a wide variety of mating behaviours. The location of female and male gonopores, the condition of the penis (coxal and sternal openings and modalities of protection), and related configurations of thoracic sternites 7 and 8, which are modified by the intercalation of a wide sternal part (thoracic sternites 7 and 8) during carcinisation, show evidence of deep homology. They represent taxonomic criteria at all ranks of the family-series and may be used to test lineages. Of particular significance are the consequences of the posterior expansion of the thoracic sternum, which influences the condition, shape, and sclerotisation of the penis, and its emergence from coxal (heterotreme) to coxo-sternal, which is actually still coxal (heterotreme), in contrast to a sternal emergence (thoracotreme). The heterotreme-thoracotreme distinction results from two different trajectories of the vas deferens and its ejaculatory duct via the P5 coxa (Heterotremata) or through the thoracic sternum (Thoracotremata). Dissections of males of several families have demonstrated that this major difference not only affects the external surface (perforation of the coxa or the sternum by the ejaculatory duct) but also the internal anatomy. There is no evidence for an ejaculatory duct passing through the articular membrane between the P5 coxa and the thoracic sternum in any Brachyura, even when the sternal male gonopore is very close to the P5 coxa. Trends towards the coxo-sternal condition are exemplified by multistate characters, varying from a shallow

  17. 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.

  18. The significance of recruiting underrepresented minorities in medicine: an examination of the need for effective approaches used in admissions by higher education institutions

    PubMed Central

    Figueroa, Obed

    2014-01-01

    The purpose of this paper is to examine the significance of recruiting underrepresented minorities in medicine (URM). This would include African Americans, Hispanics, and Native Americans. The research findings support the belief that URMs, upon graduating, are more likely to become practitioners in underserved communities, thereby becoming a resource that prompts us to find effective ways to help increase their college enrollments statewide. This paper analyzes the recruitment challenges for institutions, followed by a review of creative and effective approaches used by organizations and universities. The results have shown positive outcomes averaging a 50% increase in minority enrollments and retention. In other areas, such as cognitive development, modest gains were achieved in programs that were shorter in duration. The results nevertheless indicated steps in the right direction inspiring further program developments. PMID:25192970

  19. 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.

  20. [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.

  1. HIF-1α 1772 C/T and 1790 G/A Polymorphisms Are Significantly Associated with Higher Cancer Risk: An Updated Meta-Analysis from 34 Case-Control Studies

    PubMed Central

    Zhang, Chi; Qin, Qin; Liu, Jia; Xu, Li-Ping; Zhao, Lian-Jun; Zhang, Qu; Cai, Jing; Ma, Jian-Xin; Cheng, Hong-Yan; Sun, Xin-Chen

    2013-01-01

    Background HIF-1 activates various genes in cancer progression and metastasis. HIF-1α 1772 C/T and 1790 G/A polymorphisms are reportedly associated with cancer risk; however, the results are inconclusive. Methodology/Principal Findings A meta-analysis of 34 studies that involved 7522 cases and 9847 controls for 1772 C/T and 24 studies that involved 4884 cases and 8154 controls for 1790 G/A was conducted to identify the association of C/T and G/A polymorphisms with cancer risk. Odds ratio (OR) and 95% confidence intervals (95% CI) were used to assess the strength of association. HIF-1α 1772 C/T and 1790 G/A polymorphisms were associated with higher cancer risk in homozygote comparison (1772C/T: TT vs. CC: OR = 2.45, 95% CI: 1.52, 3.96; Pheterogeneity = 0.028; 1790G/A: AA vs. GG: OR=4.74, 95% CI: 1.78, 12.6; Pheterogeneity < 0.01), dominant model (1772C/T: TT/CT vs. CC: OR = 1.27, 95% CI: 1.04, 1.55; Pheterogeneity < 0.01, 1790G/A: AA/GA vs. GG: OR = 1.65, 95% CI: 1.05, 2.60; Pheterogeneity < 0.01), T allele versus C allele (T vs. C: OR = 1.42, 95% CI: 1.18, 1.70; Pheterogeneity < 0.01), and A allele versus G allele (A vs. G: OR = 1.83, 95% CI: 1.13, 2.96; Pheterogeneity < 0.01). On a subgroup analysis, the 1772 C/T polymorphism was significantly linked to higher risks for breast cancer, lung cancer, prostate cancer, and cervical cancer, whereas the 1790 G/A polymorphism was significantly linked to higher risks for lung cancer and prostate cancer. A significantly increased cancer risk was found in both Asians and Caucasians for 1772C/T polymorphism, whereas a significantly increased cancer risk was found in Caucasians in the heterozygote comparison and recessive model for 1790G/A polymorphism. Conclusions HIF-1α 1772 C/T and 1790 G/A polymorphisms are significantly associated with higher cancer risk. PMID:24260383

  2. 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…

  3. 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.

  4. 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.

  5. Sorbitol accumulation in heart: Implication for diabetic cardiomyopathy

    SciTech Connect

    Nakada, Tustomu; Kwee, I.L. )

    1989-01-01

    Sorbitol levels in heart were determined in streptozotocin-induced diabetic rats. Significantly higher levels were found in hearts of diabetic rats compared to normal rats. The findings are compatible with either significantly higher de novo synthesis of sorbitol in heart than is generally believed or uptake of circulating sorbitol by heart as previously indicated by nuclear magnetic resonance (NMR) in vivo metabolic imaging. Sorbitol accumulation in heart tissue may play a role in the pathogenesis of diabetic cardiomyopathy as has been implicated in cataract formation.

  6. Significantly higher activity of a cytoplasmic hammerhead ribozyme than a corresponding nuclear counterpart: engineered tRNAs with an extended 3′ end can be exported efficiently and specifically to the cytoplasm in mammalian cells

    PubMed Central

    Kuwabara, Tomoko; Warashina, Masaki; Koseki, Shiori; Sano, Masayuki; Ohkawa, Jun; Nakayama, Kazuhisa; Taira, Kazunari

    2001-01-01

    Hammerhead ribozymes were expressed under the control of similar tRNA promoters, localizing transcripts either in the cytoplasm or the nucleus. The tRNAVal-driven ribozyme (tRNA-Rz; tRNA with extra sequences at the 3′ end) that has been used in our ribozyme studies was exported efficiently into the cytoplasm and ribozyme activity was detected only in the cytoplasmic fraction. Both ends of the transported tRNA-Rz were characterized comprehensively and the results confirmed that tRNA-Rz had unprocessed 5′ and 3′ ends. Furthermore, it was also demonstrated that the activity of the exported ribozyme was significantly higher than that of the ribozyme which remained in the nucleus. We suggest that it is possible to engineer tRNA-Rz, which can be exported to the cytoplasm based on an understanding of secondary structures, and then tRNA-driven ribozymes may be co-localized with their target mRNAs in the cytoplasm of mammalian cells. PMID:11433023

  7. 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.

  8. Significantly Higher Peripheral Insulin-Like Growth Factor-1 Levels in Patients With Major Depressive Disorder or Bipolar Disorder Than in Healthy Controls: A Meta-Analysis and Review Under Guideline of PRISMA.

    PubMed

    Tu, Kun-Yu; Wu, Ming-Kung; Chen, Yen-Wen; Lin, Pao-Yen; Wang, Hung-Yu; Wu, Ching-Kuan; Tseng, Ping-Tao

    2016-01-01

    An increasing amount of research has focused on insulin-like growth factor-1 (IGF-1) because of multiple neurotrophic effects, including neurogenesis, remyelination, and synaptogenesis. In addition, IGF-1 can mediate an antidepressant effect in patients with major affective disorder, and its levels in the cerebrospinal fluid have been found to vary with antidepressant treatment. Furthermore, it has been proven to crossover the blood-brain barrier, with a reciprocal feedback loop being the central effect. However, recent studies have reported inconclusive findings about the role of IGF-1 in major affective disorder. The aim of the current study was to conduct a thorough meta-analysis of changes in peripheral IGF-1 levels in patients with major depressive disorder (MDD) or bipolar disorder (BD). We conducted a thorough literature search and compared peripheral IGF-1 levels in patients with MDD or BD and in healthy controls, and investigated clinical variables through meta-regression. Electronic research was conducted through platform of PubMed. We used inclusion criteria as clinical trials discussing comparisons of peripheral IGF-1 protein levels in patients with MDD or BD and those in healthy controls. We analyzed the cases from 9 studies with the random-effect model. The main finding was that peripheral IGF-1 levels in the patients were significantly higher than in the healthy controls (P < 0.001), with a significant inverse association with duration of illness (P = 0.03). In meta-analysis comparing peripheral IGF-1 levels in patients with BD or MDD before and after treatment, there was no significant change in peripheral IGF-1 levels after treatment (P = 0.092). The small numbers of studies and lack of correlation data with growth hormone in current studies are the main limitations of this meta-analysis. Our results indicated that peripheral IGF-1 levels may not be an indicator of disease severity, but may be a disease trait marker or an indicator of

  9. Significantly Higher Peripheral Insulin-Like Growth Factor-1 Levels in Patients With Major Depressive Disorder or Bipolar Disorder Than in Healthy Controls: A Meta-Analysis and Review Under Guideline of PRISMA.

    PubMed

    Tu, Kun-Yu; Wu, Ming-Kung; Chen, Yen-Wen; Lin, Pao-Yen; Wang, Hung-Yu; Wu, Ching-Kuan; Tseng, Ping-Tao

    2016-01-01

    An increasing amount of research has focused on insulin-like growth factor-1 (IGF-1) because of multiple neurotrophic effects, including neurogenesis, remyelination, and synaptogenesis. In addition, IGF-1 can mediate an antidepressant effect in patients with major affective disorder, and its levels in the cerebrospinal fluid have been found to vary with antidepressant treatment. Furthermore, it has been proven to crossover the blood-brain barrier, with a reciprocal feedback loop being the central effect. However, recent studies have reported inconclusive findings about the role of IGF-1 in major affective disorder. The aim of the current study was to conduct a thorough meta-analysis of changes in peripheral IGF-1 levels in patients with major depressive disorder (MDD) or bipolar disorder (BD). We conducted a thorough literature search and compared peripheral IGF-1 levels in patients with MDD or BD and in healthy controls, and investigated clinical variables through meta-regression. Electronic research was conducted through platform of PubMed. We used inclusion criteria as clinical trials discussing comparisons of peripheral IGF-1 protein levels in patients with MDD or BD and those in healthy controls. We analyzed the cases from 9 studies with the random-effect model. The main finding was that peripheral IGF-1 levels in the patients were significantly higher than in the healthy controls (P < 0.001), with a significant inverse association with duration of illness (P = 0.03). In meta-analysis comparing peripheral IGF-1 levels in patients with BD or MDD before and after treatment, there was no significant change in peripheral IGF-1 levels after treatment (P = 0.092). The small numbers of studies and lack of correlation data with growth hormone in current studies are the main limitations of this meta-analysis. Our results indicated that peripheral IGF-1 levels may not be an indicator of disease severity, but may be a disease trait marker or an indicator of

  10. Heat accumulation during sequential cortical bone drilling.

    PubMed

    Palmisano, Andrew C; Tai, Bruce L; Belmont, Barry; Irwin, Todd A; Shih, Albert; Holmes, James R

    2016-03-01

    Significant research exists regarding heat production during single-hole bone drilling. No published data exist regarding repetitive sequential drilling. This study elucidates the phenomenon of heat accumulation for sequential drilling with both Kirschner wires (K wires) and standard two-flute twist drills. It was hypothesized that cumulative heat would result in a higher temperature with each subsequent drill pass. Nine holes in a 3 × 3 array were drilled sequentially on moistened cadaveric tibia bone kept at body temperature (about 37 °C). Four thermocouples were placed at the center of four adjacent holes and 2 mm below the surface. A battery-driven hand drill guided by a servo-controlled motion system was used. Six samples were drilled with each tool (2.0 mm K wire and 2.0 and 2.5 mm standard drills). K wire drilling increased temperature from 5 °C at the first hole to 20 °C at holes 6 through 9. A similar trend was found in standard drills with less significant increments. The maximum temperatures of both tools increased from <0.5 °C to nearly 13 °C. The difference between drill sizes was found to be insignificant (P > 0.05). In conclusion, heat accumulated during sequential drilling, with size difference being insignificant. K wire produced more heat than its twist-drill counterparts. This study has demonstrated the heat accumulation phenomenon and its significant effect on temperature. Maximizing the drilling field and reducing the number of drill passes may decrease bone injury.

  11. Heat accumulation during sequential cortical bone drilling.

    PubMed

    Palmisano, Andrew C; Tai, Bruce L; Belmont, Barry; Irwin, Todd A; Shih, Albert; Holmes, James R

    2016-03-01

    Significant research exists regarding heat production during single-hole bone drilling. No published data exist regarding repetitive sequential drilling. This study elucidates the phenomenon of heat accumulation for sequential drilling with both Kirschner wires (K wires) and standard two-flute twist drills. It was hypothesized that cumulative heat would result in a higher temperature with each subsequent drill pass. Nine holes in a 3 × 3 array were drilled sequentially on moistened cadaveric tibia bone kept at body temperature (about 37 °C). Four thermocouples were placed at the center of four adjacent holes and 2 mm below the surface. A battery-driven hand drill guided by a servo-controlled motion system was used. Six samples were drilled with each tool (2.0 mm K wire and 2.0 and 2.5 mm standard drills). K wire drilling increased temperature from 5 °C at the first hole to 20 °C at holes 6 through 9. A similar trend was found in standard drills with less significant increments. The maximum temperatures of both tools increased from <0.5 °C to nearly 13 °C. The difference between drill sizes was found to be insignificant (P > 0.05). In conclusion, heat accumulated during sequential drilling, with size difference being insignificant. K wire produced more heat than its twist-drill counterparts. This study has demonstrated the heat accumulation phenomenon and its significant effect on temperature. Maximizing the drilling field and reducing the number of drill passes may decrease bone injury. PMID:26334198

  12. 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.

  13. 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

  14. 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.

  15. Spatial pattern of heavy metals accumulation risk in urban soils of Beijing and its influencing factors.

    PubMed

    Liu, Rui; Wang, Meie; Chen, Weiping; Peng, Chi

    2016-03-01

    Accumulations of heavy metals in urban soils are highly spatial heterogeneity and affected by multiple factors including soil properties, land use and pattern, population and climatic conditions. We studied accumulation risks of Cd, Cu, Pb and Zn in unban soils of Beijing and their influencing based on the regression tree analysis and a GIS-based overlay model. Result shows that Zinc causes the most extensive soil pollution and Cu result in the most acute soil pollution. The soil's organic carbon content and CEC and population growth are the most significant factors affecting heavy metal accumulation. Other influence factors in land use pattern, urban landscape, and wind speed also contributed, but less pronounced. The soils in areas with higher degree of urbanization and surrounded by intense vehicular traffics have higher accumulation risk of Cd, Cu, Pb, and Zn. PMID:26716731

  16. Spatial and temporal variability of snow accumulation in East Antarctica from traverse data

    NASA Astrophysics Data System (ADS)

    Frezzotti, Massimo; Pourchet, Michel; Flora, Onelio; Gandolfi, Stefano; Gay, Michel; Urbini, Stefano; Vincent, Christian; Becagli, Silvia; Gragnani, Roberto; Proposito, Marco; Severi, Mirko; Traversi, Rita; Udisti, Roberto; Fily, Michel

    Recent snow accumulation rate is a key quantity for ice-core and mass-balance studies. Several accumulation measurement methods (stake farm, fin core, snow-radar profiling, surface morphology, remote sensing) were used, compared and integrated at eight sites along a transect from Terra Nova Bay to Dome C, East Antarctica, to provide information about the spatial and temporal variability of snow accumulation. Thirty-nine cores were dated by identifying tritium/β marker levels (1965-66) and non-sea-salt (nss) SO42- spikes of the Tambora (Indonesia) volcanic event (1816) in order to provide information on temporal variability. Cores were linked by snow radar and global positioning system surveys to provide detailed information on spatial variability in snow accumulation. Stake-farm and ice-core accumulation rates are observed to differ significantly, but isochrones (snow radar) correlate well with ice-core derived accumulation. The accumulation/ablation pattern from stake measurements suggests that the annual local noise (metre scale) in snow accumulation can approach 2 years of ablation and more than four times the average annual accumulation, with no accumulation or ablation for a 5 year period in up to 40% of cases. The spatial variability of snow accumulation at the kilometre scale is one order of magnitude higher than temporal variability at the multi-decadal/secular scale. Stake measurements and firn cores at Dome C confirm an approximate 30% increase in accumulation over the last two centuries, with respect to the average over the last 5000 years.

  17. Accumulation of 1-deoxynojirimycin in silkworm, Bombyx mori L.

    PubMed Central

    Yin, Hao; Shi, Xin-qin; Sun, Bo; Ye, Jing-jing; Duan, Zu-an; Zhou, Xiao-ling; Cui, Wei-zheng; Wu, Xiao-feng

    2010-01-01

    1-deoxynojirimycin (1-DNJ) contents in the silkworm, Bombyx mori, at different developmental stages and tissues were investigated by using reverse-phase high-performance liquid chromatography. The 1-DNJ contents of silkworm larvae change significantly with their developmental stages. The male larvae showed higher accumulation efficiency of 1-DNJ than the females and also a significant variation was observed among the silkworm strains. The present results show that tissue distribution of 1-DNJ was significantly higher in blood, digestive juice, and alimentary canal, but no 1-DNJ was observed in the silkgland. Moreover, 1-DNJ was not found in silkworms fed with artificial diet that does not contain mulberry leaf powder. This proves that silkworms obtain 1-DNJ from mulberry leaves; they could not synthesize 1-DNJ by themselves. The accumulation and excretion of 1-DNJ change periodically during the larval stage. There was no 1-DNJ in the newly-hatched larvae and 1-DNJ was mainly accumulated during the early and middle stages of every instar, while excreted at later stages of larval development. Further, it is possible to extract 1-DNJ from the larval feces and it is optimal to develop the 1-DNJ related products for diabetic auxiliary therapy. PMID:20349525

  18. 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

  19. Drivers of Holocene peatland carbon accumulation across a climate gradient in northeastern North America

    NASA Astrophysics Data System (ADS)

    Charman, Dan J.; Amesbury, Matthew J.; Hinchliffe, William; Hughes, Paul D. M.; Mallon, Gunnar; Blake, William H.; Daley, Tim J.; Gallego-Sala, Angela V.; Mauquoy, Dmitri

    2015-08-01

    Peatlands are an important component of the Holocene global carbon (C) cycle and the rate of C sequestration and storage is driven by the balance between net primary productivity and decay. A number of studies now suggest that climate is a key driver of peatland C accumulation at large spatial scales and over long timescales, with warmer conditions associated with higher rates of C accumulation. However, other factors are also likely to play a significant role in determining local carbon accumulation rates and these may modify past, present and future peatland carbon sequestration. Here, we test the importance of climate as a driver of C accumulation, compared with hydrological change, fire, nitrogen content and vegetation type, from records of C accumulation at three sites in northeastern North America, across the N-S climate gradient of raised bog distribution. Radiocarbon age models, bulk density values and %C measurements from each site are used to construct C accumulation histories commencing between 11,200 and 8000 cal. years BP. The relationship between C accumulation and environmental variables (past water table depth, fire, peat forming vegetation and nitrogen content) is assessed with linear and multivariate regression analyses. Differences in long-term rates of carbon accumulation between sites support the contention that a warmer climate with longer growing seasons results in faster rates of long-term carbon accumulation. However, mid-late Holocene accumulation rates show divergent trends, decreasing in the north but rising in the south. We hypothesise that sites close to the moisture threshold for raised bog distribution increased their growth rate in response to a cooler climate with lower evapotranspiration in the late Holocene, but net primary productivity declined over the same period in northern areas causing a decrease in C accumulation. There was no clear relationship between C accumulation and hydrological change, vegetation, nitrogen content

  20. 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.

  1. 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

  2. Structure-property relationship for cellular accumulation of macrolones in human polymorphonuclear leukocytes (PMNs).

    PubMed

    Munić Kos, Vesna; Koštrun, Sanja; Fajdetić, Andrea; Bosnar, Martina; Kelnerić, Željko; Stepanić, Višnja; Eraković Haber, Vesna

    2013-05-13

    Macrolones are a new class of antimicrobial compounds consisting of a macrolide scaffold linked to a 4-quinolone-3-carboxylic acid moiety via C(4″) position of a macrolide. As macrolides are known to possess favorable pharmacokinetic properties by accumulating in inflammatory cells, in this study we determined the intensity of accumulation in human polymorphonuclear leukocytes (PMNs) of 57 compounds of the macrolone class and analyzed the relationship between the molecular structure and this cellular pharmacokinetic property. Accumulation of macrolones ranged from 0 to 5.5-fold higher than the standard macrolide azithromycin. Distinct structural features in all three considered molecule parts: the macrolide scaffold, quinolone moiety and the linker, affect cellular accumulation. Interestingly, while the parent macrolide, azithromycin, accumulates approximately 3-fold more than clarithromycin, among macrolones all clarithromycin derivatives accumulated in PMNs significantly more than their azithromycin counterparts. Modeling cellular accumulation of macrolones with simple molecular descriptors, as well as with the measured octanol-water distribution coefficient, revealed that the number of hydrogen bond donors and secondary amide groups negatively contribute to macrolone accumulation, while lipophilicity makes a positive contribution.

  3. 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

  4. 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

  5. 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) ...

  6. 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.

  7. 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

  8. 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.

  9. 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.

  10. 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

  11. 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

  12. Systematic engineering of phytochelatin synthesis and arsenic transport for enhanced arsenic accumulation in E. coli.

    PubMed

    Singh, Shailendra; Kang, Seung Hyun; Lee, Wonkyu; Mulchandani, Ashok; Chen, Wilfred

    2010-03-01

    Phytochelatin (PC) is a naturally occurring peptide with high affinity towards arsenic (As). In this article, we demonstrated the systematic engineering of PC-producing E. coli for As accumulation by addressing different bottlenecks in PC synthesis as well as As transport. Phytochelatin synthase from Schizosaccharomyces pombe (SpPCS) was expressed in E. coli resulting in 18 times higher As accumulation. PC production was further increased by co-expressing a feedback desensitized gamma-glutamylcysteine synthetase (GshI*), resulting in 30-fold higher PC levels and additional 2-fold higher As accumulation. The significantly increased PC levels were exploited further by co-expressing an arsenic transporter GlpF, leading to an additional 1.5-fold higher As accumulation. These engineering steps were finally combined in an arsenic efflux deletion E. coli strain to achieve an arsenic accumulation level of 16.8 micromol/g DCW, a 80-fold improvement when compared to a control strain not producing phytochelatins.

  13. Mechanisms of intrahepatic triglyceride accumulation

    PubMed Central

    Ress, Claudia; Kaser, Susanne

    2016-01-01

    Hepatic steatosis defined as lipid accumulation in hepatocytes is very frequently found in adults and obese adolescents in the Western World. Etiologically, obesity and associated insulin resistance or excess alcohol intake are the most frequent causes of hepatic steatosis. However, steatosis also often occurs with chronic hepatitis C virus (HCV) infection and is also found in rare but potentially life-threatening liver diseases of pregnancy. Clinical significance and outcome of hepatic triglyceride accumulation are highly dependent on etiology and histological pattern of steatosis. This review summarizes current concepts of pathophysiology of common causes of hepatic steatosis, including non-alcoholic fatty liver disease (NAFLD), alcoholic fatty liver disease, chronic HCV infections, drug-induced forms of hepatic steatosis, and acute fatty liver of pregnancy. Regarding the pathophysiology of NAFLD, this work focuses on the close correlation between insulin resistance and hepatic triglyceride accumulation, highlighting the potential harmful effects of systemic insulin resistance on hepatic metabolism of fatty acids on the one side and the role of lipid intermediates on insulin signalling on the other side. Current studies on lipid droplet morphogenesis have identified novel candidate proteins and enzymes in NAFLD. PMID:26819531

  14. [Fluoride accumulation and distribution in mulberry insects near fluoride pollution sources].

    PubMed

    Chen, Yuyin; Lu, Shenggao

    2002-01-01

    Fluoride accumulation and the relative fluoride loading of different body parts in wild mulberry silkworm (Bombyx mandarina M.), mulberry geometrid (Pathonandria atrineata B.), and mulberry silkworm (Bombyx mori L.) near fluoride pollution sources were studied. Comparison of the fluoride content of insect bodies and mulberry leaves showed that insects collected from polluted sites had increased fluoride accumulation. The digestive tract of the insect had much higher fluoride content than the other parts of the body and was considered to be the important organ of fluoride accumulation. There were also wide differences in fluoride accumulation between different insect species within the same polluted site. The highly significantly correlation between fluoride contents of wild mulberry silkworm, mulberry geometrid, and mulberry silkworm with that of the mulberry leaves on which they were collected was found.

  15. 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

  16. 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.

  17. Sodium accumulation in Atriplex. Final report

    SciTech Connect

    Norton, J.A.; Caldwell, M.M.; Richardson, S.G.

    1984-09-01

    This study was undertaken to determine the ecological significance and the significance to arid land reclamation of sodium accumulation and nonaccumulation in Atriplex. There was a continuum in the genetic tendency of Atriplex canescens to accumulate sodium, from populations which accumulated almost no sodium to populations which accumulated up to 7% in the leaves. There were also substantial differences in sodium uptake between populations of A. tridentata, A. falcata and A. gardneri, with some populations having less than 0.1% leaf sodium and other populations having up to 5 or 6%. In three experiments (a field study, a greenhouse pot study and a hydroponics study) there were no significant differences in salinity tolerance between sodium accumulating and nonaccumulating A. canescens: both genotypes were highly salt tolerant. There was a significant buildup of sodium in the soil beneath sodium accumulating Atriplex plants, both in natural populations and on revegetated oil shale study plots. The sodium buildup was not sufficient to be detrimental to the growth or establishment of most herbaceous species, but with older Atriplex plants or with more saline soil, the buildup could potentially be detrimental. 14 references, 42 figures, 3 tables.

  18. 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.

  19. 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)

  20. 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.

  1. 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

  2. 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.

  3. Observations, theory, and modeling of the differential accumulation of Antarctic megadunes

    NASA Astrophysics Data System (ADS)

    Dadic, Ruzica; Mott, Rebecca; Horgan, Huw J.; Lehning, Michael

    2013-12-01

    Antarctic megadunes are characterized by significant spatial differences in accumulation rate, with higher accumulation on the windward side and near-zero accumulation on the lee side. This leads to spatial differences in physical properties of snow and surface roughness, as well as to the upwind migration of the megadunes. While previous studies agree that megadunes are a result of complex interactions between wind, topography, and snow, it is not clear how they form or why they accumulate on the windward side. Here we use ICESat observations, dimensional analysis, and atmospheric flow modeling to investigate what conditions are responsible for the accumulation patterns and upwind migration of the megadunes. First, we use ICESat data to quantify the pattern of differential surface elevation change across the megadunes. We then use dimensional analysis based on supercritical-flow theory and atmospheric flow modeling to show that the megadunes topography and a stable atmosphere will always lead to upwind dune migration. We show that a combination of persistent katabatic winds, strong stability, and spatial variability in surface roughness is responsible for the accumulation on the upwind slope and hence the upwind migration of the megadunes. We further show that spatial differences in surface roughness are the primary control on accumulation magnitudes and hence dune migration velocity. The dune migration velocity in turn influences the degree of snow-metamorphism and the physical properties of snow that are relevant for paleoclimate records. Our findings pertain to the ongoing evolution of the megadunes, but their genesis remains an open question.

  4. 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…

  5. 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…

  6. 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)…

  7. 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…

  8. 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…

  9. 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.

  10. 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

  11. Molybdenum accumulation, tolerance and molybdenum-selenium-sulfur interactions in Astragalus selenium hyperaccumulator and nonaccumulator species.

    PubMed

    DeTar, Rachael Ann; Alford, Élan R; Pilon-Smits, Elizabeth A H

    2015-07-01

    Some species hyperaccumulate selenium (Se) upwards of 0.1% of dry weight. This study addressed whether Se hyperaccumulators also accumulate and tolerate more molybdenum (Mo). A field survey revealed on average 2-fold higher Mo levels in three hyperaccumulator Astragali compared to three nonaccumulator Astragali, which were not significantly different. Next, a controlled study was performed where hyperaccumulators Astragalus racemosus and Astragalus bisulcatus were compared with nonaccumulators Astragalus drummondii and Astragalus convallarius for Mo accumulation and tolerance, alone or in the presence of Se. When grown on agar media with 0, 12, 24 or 48 mg L(-1) molybdate and/or 0, 1.6 or 3.2 mg L(-1) selenate, all species decreased in biomass with increasing Mo supply. Selenium did not impact biomass at the supplied levels. All Astragali accumulated Mo upwards of 0.1% of dry weight. Selenium levels were up to 0.08% in Astragalus racemosus and 0.04% Se in the other species. Overall, there was no correlation between Se hyperaccumulation and Mo accumulation capacity. However, the hyperaccumulators and nonaccumulators differed in some respects. While none of the species had a higher tissue Mo to sulfur (S) ratio than the growth medium, nonaccumulators had a higher Mo/S ratio than hyperaccumulators. Also, while molybdate and selenate reduced S accumulation in nonaccumulators, it did not in hyperaccumulators. Furthermore, A. racemosus had a higher Se/S ratio than its medium, while the other species did not. Additionally, Mo and Se treatment affected S levels in nonaccumulators, but not in hyperaccumulators. In conclusion, there is no evidence of a link between Se and Mo accumulation and tolerance in Astragalus. Sulfate transporters in hyperaccumulating Astragali appear to have higher sulfate specificity over other oxyanions, compared to nonaccumulators, and A. racemosus may have a transporter with enhanced selenate specificity relative to sulfate or molybdate.

  12. 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

  13. 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

  14. 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.

  15. 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

  16. 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

  17. 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.

  18. 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.

  19. A resource evaluation of the Bakken Formation (Upper Devonian and Lower Mississippian) continuous oil accumulation, Williston Basin, North Dakota and Montana

    USGS Publications Warehouse

    Schmoker, J.W.

    1996-01-01

    The Upper Devonian and Lower Mississippian Bakken Formation in the United States portion of the Williston Basin is both the source and the reservoir for a continuous oil accumulation - in effect a single very large field - underlying approximately 17,800 mi2 (46,100 km2) of North Dakota and Montana. Within this area, the Bakken Formation continuous oil accumulation is not significantly influenced by the water column and cannot be analyzed in terms of conventional, discrete fields. Rather, the continuous accumulation can be envisioned as a collection of oil-charged cells, virtually all of which are capable of producing some oil, but which vary significantly in their production characteristics. Better wellperformance statistics are linked regionally to higher levels of thermal maturity and to lower levels of reservoir heterogeneity. Although portions of the Bakken Formation continuous oil accumulation have reached a mature stage of development, the accumulation as a whole is far from depleted.

  20. 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…

  1. 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

  2. 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.

  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. 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

  5. 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.

  6. 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

  7. Heterologous expression of Ceratophyllum demersum phytochelatin synthase, CdPCS1, in rice leads to lower arsenic accumulation in grain.

    PubMed

    Shri, Manju; Dave, Richa; Diwedi, Sanjay; Shukla, Devesh; Kesari, Ravi; Tripathi, Rudra Deo; Trivedi, Prabodh Kumar; Chakrabarty, Debasis

    2014-07-22

    Recent studies have identified rice (Oryza sativa) as a major dietary source of inorganic arsenic (As) and poses a significant human health risk. The predominant model for plant detoxification of heavy metals is complexation of heavy metals with phytochelatins (PCs), synthesized non-translationally by PC synthase (PCS) and compartmentalized in vacuoles. In this study, in order to restrict As in the rice roots as a detoxification mechanism, a transgenic approach has been followed through expression of phytochelatin synthase, CdPCS1, from Ceratophyllum demersum, an aquatic As-accumulator plant. CdPCS1 expressing rice transgenic lines showed marked increase in PCS activity and enhanced synthesis of PCs in comparison to non-transgenic plant. Transgenic lines showed enhanced accumulation of As in root and shoot. This enhanced metal accumulation potential of transgenic lines was positively correlated to the content of PCs, which also increased several-fold higher in transgenic lines. However, all the transgenic lines accumulated significantly lower As in grain and husk in comparison to non-transgenic plant. The higher level of PCs in transgenic plants relative to non-transgenic presumably allowed sequestering and detoxification of higher amounts of As in roots and shoots, thereby restricting its accumulation in grain.

  8. Heterologous expression of Ceratophyllum demersum phytochelatin synthase, CdPCS1, in rice leads to lower arsenic accumulation in grain.

    PubMed

    Shri, Manju; Dave, Richa; Diwedi, Sanjay; Shukla, Devesh; Kesari, Ravi; Tripathi, Rudra Deo; Trivedi, Prabodh Kumar; Chakrabarty, Debasis

    2014-01-01

    Recent studies have identified rice (Oryza sativa) as a major dietary source of inorganic arsenic (As) and poses a significant human health risk. The predominant model for plant detoxification of heavy metals is complexation of heavy metals with phytochelatins (PCs), synthesized non-translationally by PC synthase (PCS) and compartmentalized in vacuoles. In this study, in order to restrict As in the rice roots as a detoxification mechanism, a transgenic approach has been followed through expression of phytochelatin synthase, CdPCS1, from Ceratophyllum demersum, an aquatic As-accumulator plant. CdPCS1 expressing rice transgenic lines showed marked increase in PCS activity and enhanced synthesis of PCs in comparison to non-transgenic plant. Transgenic lines showed enhanced accumulation of As in root and shoot. This enhanced metal accumulation potential of transgenic lines was positively correlated to the content of PCs, which also increased several-fold higher in transgenic lines. However, all the transgenic lines accumulated significantly lower As in grain and husk in comparison to non-transgenic plant. The higher level of PCs in transgenic plants relative to non-transgenic presumably allowed sequestering and detoxification of higher amounts of As in roots and shoots, thereby restricting its accumulation in grain. PMID:25048298

  9. Heterologous expression of Ceratophyllum demersum phytochelatin synthase, CdPCS1, in rice leads to lower arsenic accumulation in grain

    PubMed Central

    Shri, Manju; Dave, Richa; Diwedi, Sanjay; Shukla, Devesh; Kesari, Ravi; Tripathi, Rudra Deo; Trivedi, Prabodh Kumar; Chakrabarty, Debasis

    2014-01-01

    Recent studies have identified rice (Oryza sativa) as a major dietary source of inorganic arsenic (As) and poses a significant human health risk. The predominant model for plant detoxification of heavy metals is complexation of heavy metals with phytochelatins (PCs), synthesized non-translationally by PC synthase (PCS) and compartmentalized in vacuoles. In this study, in order to restrict As in the rice roots as a detoxification mechanism, a transgenic approach has been followed through expression of phytochelatin synthase, CdPCS1, from Ceratophyllum demersum, an aquatic As-accumulator plant. CdPCS1 expressing rice transgenic lines showed marked increase in PCS activity and enhanced synthesis of PCs in comparison to non-transgenic plant. Transgenic lines showed enhanced accumulation of As in root and shoot. This enhanced metal accumulation potential of transgenic lines was positively correlated to the content of PCs, which also increased several-fold higher in transgenic lines. However, all the transgenic lines accumulated significantly lower As in grain and husk in comparison to non-transgenic plant. The higher level of PCs in transgenic plants relative to non-transgenic presumably allowed sequestering and detoxification of higher amounts of As in roots and shoots, thereby restricting its accumulation in grain. PMID:25048298

  10. 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.

  11. Dynamics of soil nitrogen and carbon accumulation for 61 years after agricultural abandonment

    SciTech Connect

    Knops, J.M.H.; Tilman, D.

    2000-01-01

    The authors used two independent methods to determine the dynamics of soil carbon and nitrogen following abandonment of agricultural fields on a Minnesota sand plain. First, they used a chronosequence of 19 fields abandoned from 1927 to 1982 to infer soil carbon and nitrogen dynamics. Second, they directly observed dynamics of carbon and nitrogen over a 12-yr period in 1900 permanent plots in these fields. These observed dynamics were used in a differential equation model to predict soil carbon and nitrogen dynamics. The two methods yielded similar results. Resampling the 1,900 plots showed that the rates of accumulation of nitrogen and carbon over 12 yr depended on ambient carbon and nitrogen levels in the soil, with rates of accumulation declining at higher carbon and nitrogen levels. A dynamic model fitted to the observed rates of change predicted logistic dynamics for nitrogen and carbon accumulation. On average, agricultural practices resulted in a 75% loss of soil nitrogen and an 89% loss of soil carbon at the time of abandonment. Recovery to 95% of the preagricultural levels is predicted the soil carbon, nitrogen, and carbon:nitrogen ratio patterns observed in the chronosequence of old fields, suggesting that the chronosequence may be indicative of actual changes in soil carbon and nitrogen. Their results suggest that the rate of carbon accumulation was controlled by the rate of nitrogen accumulation, which in turn depended on atmospheric nitrogen deposition and symbiotic nitrogen fixation by legumes. Their data support the hypothesis that these abandoned fields initially retain essentially all nitrogen and have a closed nitrogen cycle. Multiple regression suggests that vegetation composition had a significant influence on the rates of accumulation of both nitrogen and carbon; legumes increased these rates, and C{sub 3} grasses and forbs decreased them. C{sub 4} grasses increased the C:N ratio of the soil organic matter and thereby increased the rate of

  12. Determinants of iron accumulation in the normal aging brain.

    PubMed

    Pirpamer, Lukas; Hofer, Edith; Gesierich, Benno; De Guio, François; Freudenberger, Paul; Seiler, Stephan; Duering, Marco; Jouvent, Eric; Duchesnay, Edouard; Dichgans, Martin; Ropele, Stefan; Schmidt, Reinhold

    2016-07-01

    In a recent postmortem study, R2* relaxometry in gray matter (GM) of the brain has been validated as a noninvasive measure for iron content in brain tissue. Iron accumulation in the normal aging brain is a common finding and relates to brain maturation and degeneration. The goal of this study was to assess the determinants of iron accumulation during brain aging. The study cohort consisted of 314 healthy community-dwelling participants of the Austrian Stroke Prevention Study. Their age ranged from 38-82 years. Quantitative magnetic resonance imaging was performed on 3T and included R2* mapping, based on a 3D multi-echo gradient echo sequence. The median of R2* values was measured in all GM regions, which were segmented automatically using FreeSurfer. We investigated 25 possible determinants for cerebral iron deposition. These included demographics, brain volume, lifestyle factors, cerebrovascular risk factors, serum levels of iron, and single nucleotide polymorphisms related to iron regulating genes (rs1800562, rs3811647, rs1799945, and rs1049296). The body mass index (BMI) was significantly related to R2* in 15/32 analyzed brain regions with the strongest correlations found in the amygdala (p = 0.0091), medial temporal lobe (p = 0.0002), and hippocampus (p ≤ 0.0001). Further associations to R2* values were found in deep GM for age and smoking. No significant associations were found for gender, GM volume, serum levels of iron, or iron-associated genetic polymorphisms. In conclusion, besides age, the BMI and smoking are the only significant determinants of brain iron accumulation in normally aging subjects. Smoking relates to iron deposition in the basal ganglia, whereas higher BMI is associated with iron content in the neocortex following an Alzheimer-like distribution. PMID:27255824

  13. 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.

  14. 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

  15. 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

  16. 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.

  17. Country's Competitiveness and Sustainability in the Context of the Higher Education System Reforms

    ERIC Educational Resources Information Center

    Jermolajeva, Elita; Aleksejeva, Ludmila

    2013-01-01

    The accumulation of knowledge and its use have become important factors that promote economic development as they contribute to a country's competitiveness in the global economy. The basic significance of research is obtained by defining new approaches in the organisation, function and efficiency of the higher education system (HES) by emphasising…

  18. 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.

  19. Geomorphic control of landscape carbon accumulation

    USGS Publications Warehouse

    Rosenbloom, N.A.; Harden, J.W.; Neff, J.C.; Schimel, D.S.

    2006-01-01

    We use the CREEP process-response model to simulate soil organic carbon accumulation in an undisturbed prairie site in Iowa. Our primary objectives are to identify spatial patterns of carbon accumulation, and explore the effect of erosion on basin-scale C accumulation. Our results point to two general findings. First, redistribution of soil carbon by erosion results in a net increase in basin-wide carbon storage relative to a noneroding environment. Landscape-average mean residence times are increased in an eroding landscape owing to the burial/preservation of otherwise labile C. Second, field observations taken along a slope transect may overlook significant intraslope variations in carbon accumulation. Spatial patterns of modeled deep C accumulation are complex. While surface carbon with its relatively short equilibration time is predictable from surface properties, deep carbon is strongly influenced by the landscape's geomorphic and climatic history, resulting in wide spatial variability. Convergence and divergence associated with upland swales and interfluves result in bimodal carbon distributions in upper and mid slopes; variability in carbon storage within modeled mid slopes was as high as simulated differences between erosional shoulders and depositional valley bottoms. The bimodality of mid-slope C variability in the model suggests that a three-dimensional sampling strategy is preferable over the traditional two-dimensional analog or "catena" approach. Copyright 2006 by the American Geophysical Union.

  20. 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.

  1. [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

  2. Comparative Ni tolerance and accumulation potentials between Mesembryanthemum crystallinum (halophyte) and Brassica juncea: Metal accumulation, nutrient status and photosynthetic activity.

    PubMed

    Amari, Taoufik; Ghnaya, Tahar; Debez, Ahmed; Taamali, Manel; Ben Youssef, Nabil; Lucchini, Giorgio; Sacchi, Gian Attilio; Abdelly, Chedly

    2014-11-01

    Saline soils often constitute sites of accumulation of industrial and urban wastes contaminated by heavy metals. Halophytes, i.e. native salt-tolerant species, could be more suitable for heavy metal phytoextraction from saline areas than glycophytes, most frequently used so far. In the framework of this approach, we assess here the Ni phytoextraction potential in the halophyte Mesembryanthemum crystallinum compared with the model species Brassica juncea. Plants were hydroponically maintained for 21 days at 0, 25, 50, and 100μM NiCl2. Nickel addition significantly restricted the growth activity of both species, and to a higher extent in M. crystallinum, which did not, however, show Ni-related toxicity symptoms on leaves. Interestingly, photosynthesis activity, chlorophyll content and photosystem II integrity assessed by chlorophyll fluorescence were less impacted in Ni-treated M. crystallinum as compared to B. juncea. The plant mineral nutrition was differently affected by NiCl2 exposure depending on the element, the species investigated and even the organ. In both species, roots were the preferential sites of Ni(2+) accumulation, but the fraction translocated to shoots was higher in B. juncea than in M. crystallinum. The relatively good tolerance of M. crystallinum to Ni suggests that this halophyte species could be used in the phytoextraction of moderately polluted saline soils. PMID:25171515

  3. Influence of toxic cyanobacteria on community structure and microcystin accumulation of freshwater molluscs.

    PubMed

    Gérard, Claudia; Poullain, Virginie; Lance, Emilie; Acou, Anthony; Brient, Luc; Carpentier, Alexandre

    2009-02-01

    Community structure and microcystin accumulation of freshwater molluscs were studied before and after cyanobacterial proliferations, in order to assess the impact of toxic blooms on molluscs and the risk of microcystin transfer in food web. Observed decrease in mollusc abundance and changes in species richness in highly contaminated waters were not significant; however, relative abundances of taxa (prosobranchs, pulmonates, bivalves) were significantly different before and after cyanobacterial bloom. Pulmonates constituted the dominant taxon, and bivalves never occurred after bloom. Microcystin accumulation was significantly higher in molluscs from highly (versus lowly) contaminated waters, in adults (versus juveniles) and in pulmonates (versus prosobranchs and bivalves). Results are discussed according to the ecology of molluscs, their sensitivity and their ability to detoxify.

  4. 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…

  5. 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.

  6. 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

  7. 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

  8. Effect of transpiration on plant accumulation and translocation of PPCP/EDCs.

    PubMed

    Dodgen, Laurel K; Ueda, Aiko; Wu, Xiaoqin; Parker, David R; Gan, Jay

    2015-03-01

    The reuse of treated wastewater for agricultural irrigation in arid and hot climates where plant transpiration is high may affect plant accumulation of pharmaceutical and personal care products (PPCPs) and endocrine disrupting chemicals (EDCs). In this study, carrot, lettuce, and tomato plants were grown in solution containing 16 PPCP/EDCs in either a cool-humid or a warm-dry environment. Leaf bioconcentration factors (BCF) were positively correlated with transpiration for chemical groups of different ionized states (p < 0.05). However, root BCFs were correlated with transpiration only for neutral PPCP/EDCs (p < 0.05). Neutral and cationic PPCP/EDCs showed similar accumulation, while anionic PPCP/EDCs had significantly higher accumulation in roots and significantly lower accumulation in leaves (p < 0.05). Results show that plant transpiration may play a significant role in the uptake and translocation of PPCP/EDCs, which may have a pronounced effect in arid and hot climates where irrigation with treated wastewater is common.

  9. Effect of Transpiration on Plant Accumulation and Translocation of PPCP/EDCs

    PubMed Central

    Dodgen, Laurel K; Ueda, Aiko; Wu, Xiaoqin; Parker, David R; Gan, Jay

    2015-01-01

    The reuse of treated wastewater for agricultural irrigation in arid and hot climates where plant transpiration is high may affect plant accumulation of pharmaceutical and personal care products (PPCPs) and endocrine disrupting chemicals (EDCs). In this study, carrot, lettuce, and tomato plants were grown in solution containing 16 PPCP/EDCs in either a cool-humid or a warm-dry environment. Leaf bioconcentration factors (BCF) were positively correlated with transpiration for chemical groups of different ionized states (p < 0.05). However, root BCFs were correlated with transpiration only for neutral PPCP/EDCs (p < 0.05). Neutral and cationic PPCP/EDCs showed similar accumulation, while anionic PPCP/EDCs had significantly higher accumulation in roots and significantly lower accumulation in leaves (p < 0.05). Results show that plant transpiration may play a significant role in the uptake and translocation of PPCP/EDCs, which may have a pronounced effect in arid and hot climates where irrigation with treated wastewater is common. PMID:25594843

  10. Effect of transpiration on plant accumulation and translocation of PPCP/EDCs.

    PubMed

    Dodgen, Laurel K; Ueda, Aiko; Wu, Xiaoqin; Parker, David R; Gan, Jay

    2015-03-01

    The reuse of treated wastewater for agricultural irrigation in arid and hot climates where plant transpiration is high may affect plant accumulation of pharmaceutical and personal care products (PPCPs) and endocrine disrupting chemicals (EDCs). In this study, carrot, lettuce, and tomato plants were grown in solution containing 16 PPCP/EDCs in either a cool-humid or a warm-dry environment. Leaf bioconcentration factors (BCF) were positively correlated with transpiration for chemical groups of different ionized states (p < 0.05). However, root BCFs were correlated with transpiration only for neutral PPCP/EDCs (p < 0.05). Neutral and cationic PPCP/EDCs showed similar accumulation, while anionic PPCP/EDCs had significantly higher accumulation in roots and significantly lower accumulation in leaves (p < 0.05). Results show that plant transpiration may play a significant role in the uptake and translocation of PPCP/EDCs, which may have a pronounced effect in arid and hot climates where irrigation with treated wastewater is common. PMID:25594843

  11. Spatial and temporal variations in sediment accumulation and their impacts on coral communities in the Sanya Coral Reef Reserve, Hainan, China

    NASA Astrophysics Data System (ADS)

    Li, Xiu-bao; Huang, Hui; Lian, Jian-sheng; Liu, Sheng; Huang, Liang-min; Yang, Jian-hui

    2013-11-01

    This study investigated the spatial and temporal variations of sediment accumulation and their impacts on coral communities in four sites at two or three depths (3 m, 6 m and 9 m) at the Sanya Coral Reef Reserve by deploying sediment traps on the sea floor during 2007-2009. Rainfall and typhoon events, which appeared to control sediment accumulation in the sea floor of the coral reef, were positively correlated with total sediment and sand-sized (i.e. 63-2000 µm) sediment accumulation. Sediment accumulation rate significantly decreased with the distance far away from the coast in Sanya. The mean sediment accumulation rates in Ximaozhou, Luhuitou and Xiaodonghai during 2007 to 2009 were close to 20 mg cm-2 d-1, and they were significantly higher than that in Yalongwan, probably as a result of terrestrial soil erosion caused by strong coast human activities (e.g. coastal construction, dredging and hillside clearing). Correlation analysis revealed that silt-clay-sized sediment accumulation rate was highly negatively correlated with total live coral cover and coral cover in some taxa, such as Montipora and branching Porites. whereas, Diploastrea heliopora was positively correlated with silt-clay-sized sediment accumulation. Correlation analysis also suggested that silt-clay-sized sediment accumulation had a higher efficiency in predicting the spatial variation of total live coral cover in Sanya than did the total sediment accumulation. Based on this investigation, we conclude that high rates of sediment accumulation pose a severe threat to the Sanya Coral Reef Reserve, highlighting the importance of integrated watershed management practices in the Sanya Coral Reef Reserve.

  12. Large spin accumulation near a resistive interface due to spin-charge coupling

    SciTech Connect

    Chen, Shuhan; Zou, Han; Chui, Siu-Tat; Ji, Yi

    2013-12-14

    We experimentally and theoretically investigate large spin signals in special nonlocal spin valves, where a vacuum break-junction is formed between the ferromagnetic spin detector and the nonmagnetic channel. The spin signals are clearly nonlocal and can be either non-inverted (meaning high nonlocal resistance for parallel states and low resistance for antiparallel states) or inverted. The magnitudes are significantly larger than those of standard metallic nonlocal devices with similar dimensions. The magnitudes and the signs can be understood by a theory of spin-charge coupling. The coupling between spin accumulation and charge accumulation across a resistive break junction leads to a large interfacial spin accumulation and thereby large spin signals. By analyzing the profiles of electrochemical potentials near the interface, we show that the sign of the spin signal depends on the values of spin-dependent conductivities, diffusion constants, and densities of states. The magnitude of the spin accumulation in the ferromagnetic spin detector can be higher than that in the nonmagnetic channel, enabling a rare amplification effect for spin accumulation.

  13. 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

  14. 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

  15. 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.

  16. Trehalose accumulation enhances tolerance of Saccharomyces cerevisiae to acetic acid.

    PubMed

    Yoshiyama, Yoko; Tanaka, Koichi; Yoshiyama, Kohei; Hibi, Makoto; Ogawa, Jun; Shima, Jun

    2015-02-01

    Trehalose confers protection against various environmental stresses on yeast cells. In this study, trehalase gene deletion mutants that accumulate trehalose at high levels showed significant stress tolerance to acetic acid. The enhancement of trehalose accumulation can thus be considered a target in the breeding of acetic acid-tolerant yeast strains.

  17. Lipid accumulation by oleaginous and non-oleaginous yeast strains in nitrogen and phosphate limitation.

    PubMed

    Kolouchová, Irena; Maťátková, Olga; Sigler, Karel; Masák, Jan; Řezanka, Tomáš

    2016-09-01

    We investigated the possibility of utilizing both oleaginous yeast species accumulating large amounts of lipids (Yarrowia lipolytica, Rhodotorula glutinis, Trichosporon cutaneum, Candida sp.) and traditional biotechnological non-oleaginous ones characterized by high biomass yield (Kluyveromyces polysporus, Torulaspora delbrueckii, Saccharomyces cerevisiae) as potential producers of biofuel-utilizable and nutritionally valuable lipids. The main objective was to increase lipid accumulation by increasing C/P ratio together with higher C/N ratio, while maintaining high biomass yield. The C/N ratio of 30 was found to lead to higher biomass content and the total lipid content increased significantly with higher C/P ratio. With higher ratios of both C/N and C/P, the content of monounsaturated fatty acids (FAs) in cell lipids increased while polyunsaturated FAs decreased. Oleaginous yeast species had a lower proportion of unsaturated FAs (approx. 80 %) than non-oleaginous strains (approx. 90 %). At a C/N ratio of 30 and C/P ratio 1043, T. cutaneum produced a high amount of ω-6 unsaturated linoleic acid, the precursor of some prostaglandins, leukotrienes, and thromboxanes, while Candida sp. and K. polysporus accumulated a high content of palmitoleic acid.

  18. Gypsum accumulation on carbonate stone

    USGS Publications Warehouse

    McGee, E.S.; Mossotti, V.G.

    1992-01-01

    The accumulation of gypsum on carbonate stone has been investigated through exposure of fresh samples of limestone and marble at monitored sites, through examination of alteration crusts from old buildings and through laboratory experiments. Several factors contribute to gypsum accumulation on carbonate stone. Marble or limestone that is sheltered from direct washing by rain in an urban environment with elevated pollution levels is likely to accumulate a gypsum crust. Crust development may be enhanced if the stone is porous or has an irregular surface area. Gypsum crusts are a surficial alteration feature; gypsum crystals form at the pore opening-air interface, where evaporation is greatest.

  19. Accumulative Tritium Transfer from Water into Biosystems

    SciTech Connect

    Baumgaertner, Franz

    2005-07-15

    The energy balance of hydrogen isotopes in H bonds of water and biomolecules results in accumulative tritium transfer from water into biomolecules. Tests of DNA dissolved in tritiated water and of maize or barley hydroponically grown in tritiated water confirm the increase. The primary hydration shell of DNA shows an accumulation factor of {approx}1.4, and the exchangeable hydrogens inside DNA show {approx}2. Logistic growth analyses of maize and barley reveal the intrinsic growth rates of tritium 1.3 and 1.2 times larger than that of hydrogen. The higher rate of tritium than hydrogen incorporation in solid biomatter is caused by the hydration shells, which constitute an intrinsic component of biomolecules.

  20. High Rates of Species Accumulation in Animals with Bioluminescent Courtship Displays.

    PubMed

    Ellis, Emily A; Oakley, Todd H

    2016-07-25

    One of the great mysteries of evolutionary biology is why closely related lineages accumulate species at different rates. Theory predicts that populations undergoing strong sexual selection will more quickly differentiate because of increased potential for genetic isolation [1-6]. Whether or not these population genetic processes translate to more species at macroevolutionary scales remains contentious [7]. Here we show that lineages with bioluminescent courtship, almost certainly a sexually selected trait, have more species and faster rates of species accumulation than their non-luminous relatives. In each of ten distantly related animal lineages from insects, crustaceans, annelid worms, and fishes, we find more species in lineages with bioluminescent courtship compared to their sister groups. Furthermore, we find under a Yule model that lineages with bioluminescent courtship displays have significantly higher rates of species accumulation compared to a larger clade that includes them plus non-luminous relatives. In contrast, we do not find more species or higher rates in lineages that use bioluminescence for defense, a function presumably not under sexual selection. These results document an association between the origin of bioluminescent courtship and increased accumulation of species, supporting theory predicting sexual selection increases rates of speciation at macroevolutionary scales to influence global patterns of biodiversity. PMID:27345160

  1. Accumulation of Poly(3-hydroxybutyrate) Helps Bacterial Cells to Survive Freezing

    PubMed Central

    Krzyzanek, Vladislav; Mravec, Filip; Hrubanova, Kamila; Samek, Ota; Kucera, Dan; Benesova, Pavla; Marova, Ivana

    2016-01-01

    Accumulation of polyhydroxybutyrate (PHB) seems to be a common metabolic strategy adopted by many bacteria to cope with cold environments. This work aimed at evaluating and understanding the cryoprotective effect of PHB. At first a monomer of PHB, 3-hydroxybutyrate, was identified as a potent cryoprotectant capable of protecting model enzyme (lipase), yeast (Saccharomyces cerevisiae) and bacterial cells (Cupriavidus necator) against the adverse effects of freezing-thawing cycles. Further, the viability of the frozen–thawed PHB accumulating strain of C. necator was compared to that of the PHB non-accumulating mutant. The presence of PHB granules in cells was revealed to be a significant advantage during freezing. This might be attributed to the higher intracellular level of 3-hydroxybutyrate in PHB accumulating cells (due to the action of parallel PHB synthesis and degradation, the so-called PHB cycle), but the cryoprotective effect of PHB granules seems to be more complex. Since intracellular PHB granules retain highly flexible properties even at extremely low temperatures (observed by cryo-SEM), it can be expected that PHB granules protect cells against injury from extracellular ice. Finally, thermal analysis indicates that PHB-containing cells exhibit a higher rate of transmembrane water transport, which protects cells against the formation of intracellular ice which usually has fatal consequences. PMID:27315285

  2. Accumulation of Poly(3-hydroxybutyrate) Helps Bacterial Cells to Survive Freezing.

    PubMed

    Obruca, Stanislav; Sedlacek, Petr; Krzyzanek, Vladislav; Mravec, Filip; Hrubanova, Kamila; Samek, Ota; Kucera, Dan; Benesova, Pavla; Marova, Ivana

    2016-01-01

    Accumulation of polyhydroxybutyrate (PHB) seems to be a common metabolic strategy adopted by many bacteria to cope with cold environments. This work aimed at evaluating and understanding the cryoprotective effect of PHB. At first a monomer of PHB, 3-hydroxybutyrate, was identified as a potent cryoprotectant capable of protecting model enzyme (lipase), yeast (Saccharomyces cerevisiae) and bacterial cells (Cupriavidus necator) against the adverse effects of freezing-thawing cycles. Further, the viability of the frozen-thawed PHB accumulating strain of C. necator was compared to that of the PHB non-accumulating mutant. The presence of PHB granules in cells was revealed to be a significant advantage during freezing. This might be attributed to the higher intracellular level of 3-hydroxybutyrate in PHB accumulating cells (due to the action of parallel PHB synthesis and degradation, the so-called PHB cycle), but the cryoprotective effect of PHB granules seems to be more complex. Since intracellular PHB granules retain highly flexible properties even at extremely low temperatures (observed by cryo-SEM), it can be expected that PHB granules protect cells against injury from extracellular ice. Finally, thermal analysis indicates that PHB-containing cells exhibit a higher rate of transmembrane water transport, which protects cells against the formation of intracellular ice which usually has fatal consequences. PMID:27315285

  3. Statistical or biological significance?

    PubMed

    Saxon, Emma

    2015-01-01

    Oat plants grown at an agricultural research facility produce higher yields in Field 1 than in Field 2, under well fertilised conditions and with similar weather exposure; all oat plants in both fields are healthy and show no sign of disease. In this study, the authors hypothesised that the soil microbial community might be different in each field, and these differences might explain the difference in oat plant growth. They carried out a metagenomic analysis of the 16 s ribosomal 'signature' sequences from bacteria in 50 randomly located soil samples in each field to determine the composition of the bacterial community. The study identified >1000 species, most of which were present in both fields. The authors identified two plant growth-promoting species that were significantly reduced in soil from Field 2 (Student's t-test P < 0.05), and concluded that these species might have contributed to reduced yield. PMID:26541972

  4. 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.

  5. Manganese As a Metal Accumulator

    EPA Science Inventory

    Manganese deposits in water distribution systems accumulate metals, radionuclides and oxyanions by a combination of surface complexation, adsorption and solid substitution, as well as a combination of oxidation followed by manganese reduction and sorption of the oxidized constitu...

  6. 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

  7. Snf1 Is a Regulator of Lipid Accumulation in Yarrowia lipolytica

    PubMed Central

    Seip, John; Jackson, Raymond; He, Hongxian; Zhu, Quinn

    2013-01-01

    In the oleaginous yeast Yarrowia lipolytica, de novo lipid synthesis and accumulation are induced under conditions of nitrogen limitation (or a high carbon-to-nitrogen ratio). The regulatory pathway responsible for this induction has not been identified. Here we report that the SNF1 pathway plays a key role in the transition from the growth phase to the oleaginous phase in Y. lipolytica. Strains with a Y. lipolytica snf1 (Ylsnf1) deletion accumulated fatty acids constitutively at levels up to 2.6-fold higher than those of the wild type. When introduced into a Y. lipolytica strain engineered to produce omega-3 eicosapentaenoic acid (EPA), Ylsnf1 deletion led to a 52% increase in EPA titers (7.6% of dry cell weight) over the control. Other components of the Y. lipolytica SNF1 pathway were also identified, and their function in limiting fatty acid accumulation is suggested by gene deletion analyses. Deletion of the gene encoding YlSnf4, YlGal83, or YlSak1 significantly increased lipid accumulation in both growth and oleaginous phases compared to the wild type. Furthermore, microarray and quantitative reverse transcription-PCR (qRT-PCR) analyses of the Ylsnf1 mutant identified significantly differentially expressed genes during de novo lipid synthesis and accumulation in Y. lipolytica. Gene ontology analysis found that these genes were highly enriched with genes involved in lipid metabolism. This work presents a new role for Snf1/AMP-activated protein kinase (AMPK) pathways in lipid accumulation in this oleaginous yeast. PMID:24056466

  8. 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.

  9. Ocean acidification increases cadmium accumulation in marine bivalves: a potential threat to seafood safety

    NASA Astrophysics Data System (ADS)

    Shi, Wei; Zhao, Xinguo; Han, Yu; Che, Zhumei; Chai, Xueliang; Liu, Guangxu

    2016-01-01

    To date, the effects of ocean acidification on toxic metals accumulation and the underlying molecular mechanism remains unknown in marine bivalve species. In the present study, the effects of the realistic future ocean pCO2 levels on the cadmium (Cd) accumulation in the gills, mantle and adductor muscles of three bivalve species, Mytilus edulis, Tegillarca granosa, and Meretrix meretrix, were investigated. The results obtained suggested that all species tested accumulated significantly higher Cd (p < 0.05) in the CO2 acidified seawater during the 30 days experiment and the health risk of Cd (based on the estimated target hazard quotients, THQ) via consumption of M. meretrix at pH 7.8 and 7.4 significantly increased 1.21 and 1.32 times respectively, suggesting a potential threat to seafood safety. The ocean acidification-induced increase in Cd accumulation may have occurred due to (i) the ocean acidification increased the concentration of Cd and the Cd2+/Ca2+ in the seawater, which in turn increased the Cd influx through Ca channel; (ii) the acidified seawater may have brought about epithelia damage, resulting in easier Cd penetration; and (iii) ocean acidification hampered Cd exclusion.

  10. Ocean acidification increases cadmium accumulation in marine bivalves: a potential threat to seafood safety.

    PubMed

    Shi, Wei; Zhao, Xinguo; Han, Yu; Che, Zhumei; Chai, Xueliang; Liu, Guangxu

    2016-01-21

    To date, the effects of ocean acidification on toxic metals accumulation and the underlying molecular mechanism remains unknown in marine bivalve species. In the present study, the effects of the realistic future ocean pCO2 levels on the cadmium (Cd) accumulation in the gills, mantle and adductor muscles of three bivalve species, Mytilus edulis, Tegillarca granosa, and Meretrix meretrix, were investigated. The results obtained suggested that all species tested accumulated significantly higher Cd (p < 0.05) in the CO2 acidified seawater during the 30 days experiment and the health risk of Cd (based on the estimated target hazard quotients, THQ) via consumption of M. meretrix at pH 7.8 and 7.4 significantly increased 1.21 and 1.32 times respectively, suggesting a potential threat to seafood safety. The ocean acidification-induced increase in Cd accumulation may have occurred due to (i) the ocean acidification increased the concentration of Cd and the Cd(2+)/Ca(2+) in the seawater, which in turn increased the Cd influx through Ca channel; (ii) the acidified seawater may have brought about epithelia damage, resulting in easier Cd penetration; and (iii) ocean acidification hampered Cd exclusion.

  11. 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.

  12. Ocean acidification increases cadmium accumulation in marine bivalves: a potential threat to seafood safety

    PubMed Central

    Shi, Wei; Zhao, Xinguo; Han, Yu; Che, Zhumei; Chai, Xueliang; Liu, Guangxu

    2016-01-01

    To date, the effects of ocean acidification on toxic metals accumulation and the underlying molecular mechanism remains unknown in marine bivalve species. In the present study, the effects of the realistic future ocean pCO2 levels on the cadmium (Cd) accumulation in the gills, mantle and adductor muscles of three bivalve species, Mytilus edulis, Tegillarca granosa, and Meretrix meretrix, were investigated. The results obtained suggested that all species tested accumulated significantly higher Cd (p < 0.05) in the CO2 acidified seawater during the 30 days experiment and the health risk of Cd (based on the estimated target hazard quotients, THQ) via consumption of M. meretrix at pH 7.8 and 7.4 significantly increased 1.21 and 1.32 times respectively, suggesting a potential threat to seafood safety. The ocean acidification-induced increase in Cd accumulation may have occurred due to (i) the ocean acidification increased the concentration of Cd and the Cd2+/Ca2+ in the seawater, which in turn increased the Cd influx through Ca channel; (ii) the acidified seawater may have brought about epithelia damage, resulting in easier Cd penetration; and (iii) ocean acidification hampered Cd exclusion. PMID:26795597

  13. 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

  14. 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

  15. [Absorption and accumulation of heavy metals by plants around a smelter].

    PubMed

    Cui, Shunag; Zhou, Qixing; Chao, Lei

    2006-03-01

    The study on the absorption and accumulation of heavy metals lead, zinc, copper and cadmium by 8 plant species around a smelter showed that the metals accumulation by plants differed with plant species, their parts, and kinds of metals. Abutilon theophrasti had a higher capability of absorbing and accumulating Pb, Conyza canadensis, Ambrosia trifida, Polygonumn lapathifolium, A. theophrasti, Solanum nigrum, Chenopodium acuminatum and Helianthus tuberosus had a higher capability of absorbing and accumulating Zn, C. acuminatunz and A. theophrasti had a higher capability of absorbing and accumulating Cu, and S. nigrum, C. acuminatum, A. theophrasti, P. lapathifolium and C. canadensis had a higher capability of absorbing and accumulating Cd. These plants had TF values higher than 1, and were suitable for phytoextraction to remedy polluted soil. As for the plants with TF values lower than 1, they were suitable as the phytostabilizers of heavy metals-contaminated lands. PMID:16724753

  16. [Absorption and accumulation of heavy metals by plants around a smelter].

    PubMed

    Cui, Shunag; Zhou, Qixing; Chao, Lei

    2006-03-01

    The study on the absorption and accumulation of heavy metals lead, zinc, copper and cadmium by 8 plant species around a smelter showed that the metals accumulation by plants differed with plant species, their parts, and kinds of metals. Abutilon theophrasti had a higher capability of absorbing and accumulating Pb, Conyza canadensis, Ambrosia trifida, Polygonumn lapathifolium, A. theophrasti, Solanum nigrum, Chenopodium acuminatum and Helianthus tuberosus had a higher capability of absorbing and accumulating Zn, C. acuminatunz and A. theophrasti had a higher capability of absorbing and accumulating Cu, and S. nigrum, C. acuminatum, A. theophrasti, P. lapathifolium and C. canadensis had a higher capability of absorbing and accumulating Cd. These plants had TF values higher than 1, and were suitable for phytoextraction to remedy polluted soil. As for the plants with TF values lower than 1, they were suitable as the phytostabilizers of heavy metals-contaminated lands.

  17. Mineral accumulation in vegetative and reproductive tissues during seed development in Medicago truncatula

    PubMed Central

    Garcia, Christina B.; Grusak, Michael A.

    2015-01-01

    Enhancing nutrient density in legume seeds is one of several strategies being explored to improve the nutritional quality of the food supply. In order to develop crop varieties with increased seed mineral concentration, a more detailed understanding of mineral translocation within the plant is required. By studying mineral accumulation in different organs within genetically diverse members of the same species, it may be possible to identify variable traits that modulate seed mineral concentration. We utilized two ecotypes (A17 and DZA315.16) of the model legume, Medicago truncatula, to study dry mass and mineral accumulation in the leaves, pod walls, and seeds during reproductive development. The pod wall dry mass was significantly different between the two ecotypes beginning at 12 days after pollination, whereas there was no significant difference in the average dry mass of individual seeds between the two ecotypes at any time point. There were also no significant differences in leaf dry mass between ecotypes; however, we observed expansion of A17 leaves during the first 21 days of pod development, while DZA315.16 leaves did not display a significant increase in leaf area. Mineral profiling of the leaves, pod walls, and seeds highlighted differences in accumulation patterns among minerals within each tissue as well as genotypic differences with respect to individual minerals. Because there were differences in the average seed number per pod, the total seed mineral content per pod was generally higher in A17 than DZA315.16. In addition, mineral partitioning to the seeds tended to be higher in A17 pods. These data revealed that mineral retention within leaves and/or pod walls might attenuate mineral accumulation within the seeds. As a result, strategies to increase seed mineral content should include approaches that will enhance export from these tissues. PMID:26322063

  18. Integration of algae cultivation as biodiesel production feedstock with municipal wastewater treatment: strains screening and significance evaluation of environmental factors.

    PubMed

    Li, Yecong; Zhou, Wenguang; Hu, Bing; Min, Min; Chen, Paul; Ruan, Roger R

    2011-12-01

    The objectives of this study are to find the robust strains for the centrate cultivation system and to evaluate the effect of environmental factors including light intensity, light-dark cycle, and exogenous CO2 concentration on biomass accumulation, wastewater nutrient removal and biodiesel production. The results showed that all 14 algae strains from the genus of Chlorella, Haematococcus, Scenedesmus, Chlamydomonas, and Chloroccum were able to grow on centrate. The highest net biomass accumulation (2.01 g/L) was observed with Chlorella kessleri followed by Chlorella protothecoides (1.31 g/L), and both of them were proved to be capable of mixotrophic growth when cultivated on centrate. Environmental factors had significant effect on algal biomass accumulation, wastewater nutrients removal and biodiesel production. Higher light intensity and exogenous CO2 concentration with longer lighting period promote biomass accumulation, biodiesel production, as well as the removal of chemical oxygen demand and nitrogen, while, lower exogenous CO2 concentration promotes phosphorus removal.

  19. Extrapulmonary sites of radiogallium accumulation in sarcoidosis

    SciTech Connect

    Sulavik, S.B.; Palestro, C.J.; Spencer, R.P.; Swyer, A.J.; Goldsmith, S.J.; Tierstein, A.S. )

    1990-12-01

    In an effort to detect extrapulmonary sites of radiogallium accumulation in cases of sarcoidosis, 145 separate Ga-67 citrate studies of 114 patients with biopsy-proven sarcoidosis were examined. The most characteristic extrapulmonary radiogallium uptake pattern was the panda sign in 47 patients (41%). The most common site of prominent extrapulmonary radiogallium uptake was the lacrimal glands in 101 patients (88%). Second most common was activity in one or more superficial lymph node regions such as the cervical, axillary, femoral, or inguinal in 19 patients (17%). Other extrapulmonary sites included breast uptake in 6 out of 80 women (8%), prominent splenic and nasal uptake in 9 (8%) patients, periportal accumulation in 7 (6%), and cutaneous/subcutaneous activity in 4 (4%). Because many of these individuals were receiving corticosteroids, the natural (untreated) prevalence of extrapulmonary findings may be even higher. Although the sensitivity and specificity of extrapulmonary radiogallium accumulation has still to be determined, many of the sites may be accessible to biopsy both for diagnostic purposes and to follow the effects of medications. It is therefore suggested that whole-body imaging be performed when radiogallium is administered to patients with suspected or known sarcoidosis.

  20. [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.

  1. 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.

  2. 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

  3. Solar-Panel Dust Accumulation and Cleanings

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Air-fall dust accumulates on the solar panels of NASA's Mars Exploration Rovers, reducing the amount of sunlight reaching the solar arrays. Pre-launch models predicted steady dust accumulation. However, the rovers have been blessed with occasional wind events that clear significant amounts of dust from the solar panels.

    This graph shows the effects of those panel-cleaning events on the amount of electricity generated by Spirit's solar panels. The horizontal scale is the number of Martian days (sols) after Spirit's Jan. 4, 2005, (Universal Time) landing on Mars. The vertical scale indicates output from the rover's solar panels as a fraction of the amount produced when the clean panels first opened. Note that the gradual declines are interrupted by occasional sharp increases, such as a dust-cleaning event on sol 420.

  4. 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.

  5. Maximum likelihood decoding analysis of Accumulate-Repeat-Accumulate Codes

    NASA Technical Reports Server (NTRS)

    Abbasfar, Aliazam; Divsalar, Dariush; Yao, Kung

    2004-01-01

    Repeat-Accumulate (RA) codes are the simplest turbo-like codes that achieve good performance. However, they cannot compete with Turbo codes or low-density parity check codes (LDPC) as far as performance is concerned. The Accumulate Repeat Accumulate (ARA) codes, as a subclass of LDPC codes, are obtained by adding a pre-coder in front of RA codes with puncturing where an accumulator is chosen as a precoder. These codes not only are very simple, but also achieve excellent performance with iterative decoding. In this paper, the performance of these codes with (ML) decoding are analyzed and compared to random codes by very tight bounds. The weight distribution of some simple ARA codes is obtained, and through existing tightest bounds we have shown the ML SNR threshold of ARA codes approaches very closely to the performance of random codes. We have shown that the use of precoder improves the SNR threshold but interleaving gain remains unchanged with respect to RA code with puncturing.

  6. 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).

  7. Carbon accumulation and sequestration of lakes in China during the Holocene.

    PubMed

    Wang, Mei; Chen, Huai; Yu, Zicheng; Wu, Jianghua; Zhu, Qiu'an; Peng, Changhui; Wang, Yanfen; Qin, Boqiang

    2015-12-01

    Understanding the responses of lake systems to past climate change and human activity is critical for assessing and predicting the fate of lake carbon (C) in the future. In this study, we synthesized records of the sediment accumulation from 82 lakes and of C sequestration from 58 lakes with direct organic C measurements throughout China. We also identified the controlling factors of the long-term sediment and C accumulation dynamics in these lakes during the past 12 ka (1 ka = 1000 cal yr BP). Our results indicated an overall increasing trend of sediment and C accumulation since 12 ka, with an accumulation peak in the last couple of millennia for lakes in China, corresponding to terrestrial organic matter input due to land-use change. The Holocene lake sediment accumulation rate (SAR) and C accumulation rate (CAR) averaged (mean ± SE) 0.47 ± 0.05 mm yr(-1) and 7.7 ± 1.4 g C m(-2)  yr(-1) in China, respectively, comparable to the previous estimates for boreal and temperate regions. The SAR for lakes in the East Plain of subtropical China (1.05 ± 0.28 mm yr(-1) ) was higher than those in other regions (P < 0.05). However, CAR did not vary significantly among regions. Overall, the variability and history of climate and anthropogenic interference regulated the temporal and spatial dynamics of sediment and C sequestration for lakes in China. We estimated the total amount of C burial in lakes of China as 8.0 ± 1.0 Pg C. This first estimation of total C storage and dynamics in lakes of China confirms the importance of lakes in land C budget in monsoon-influenced regions. PMID:26220607

  8. Carbon accumulation and sequestration of lakes in China during the Holocene.

    PubMed

    Wang, Mei; Chen, Huai; Yu, Zicheng; Wu, Jianghua; Zhu, Qiu'an; Peng, Changhui; Wang, Yanfen; Qin, Boqiang

    2015-12-01

    Understanding the responses of lake systems to past climate change and human activity is critical for assessing and predicting the fate of lake carbon (C) in the future. In this study, we synthesized records of the sediment accumulation from 82 lakes and of C sequestration from 58 lakes with direct organic C measurements throughout China. We also identified the controlling factors of the long-term sediment and C accumulation dynamics in these lakes during the past 12 ka (1 ka = 1000 cal yr BP). Our results indicated an overall increasing trend of sediment and C accumulation since 12 ka, with an accumulation peak in the last couple of millennia for lakes in China, corresponding to terrestrial organic matter input due to land-use change. The Holocene lake sediment accumulation rate (SAR) and C accumulation rate (CAR) averaged (mean ± SE) 0.47 ± 0.05 mm yr(-1) and 7.7 ± 1.4 g C m(-2)  yr(-1) in China, respectively, comparable to the previous estimates for boreal and temperate regions. The SAR for lakes in the East Plain of subtropical China (1.05 ± 0.28 mm yr(-1) ) was higher than those in other regions (P < 0.05). However, CAR did not vary significantly among regions. Overall, the variability and history of climate and anthropogenic interference regulated the temporal and spatial dynamics of sediment and C sequestration for lakes in China. We estimated the total amount of C burial in lakes of China as 8.0 ± 1.0 Pg C. This first estimation of total C storage and dynamics in lakes of China confirms the importance of lakes in land C budget in monsoon-influenced regions.

  9. Velocity Estimates for Signal Propagation Leading to Systemic Jasmonic Acid Accumulation in Wounded Arabidopsis*

    PubMed Central

    Glauser, Gaetan; Dubugnon, Lucie; Mousavi, Seyed A. R.; Rudaz, Serge; Wolfender, Jean-Luc; Farmer, Edward E.

    2009-01-01

    The wound response prohormone jasmonic acid (JA) accumulates rapidly in tissues both proximal and distal to injury sites in plants. Using quantitative liquid chromatography-mass spectrometry after flash freezing of tissues, we found that JA accumulated within 30 s of injury in wounded Arabidopsis leaves (p = 3.5 e−7). JA augmentation distal to wounds was strongest in unwounded leaves with direct vascular connections to wounded leaves wherein JA levels increased significantly within 120 s of wounding (p = 0.00027). This gave conservative and statistically robust temporal boundaries for the average velocity of the long distance signal leading to distal JA accumulation in unwounded leaves of 3.4–4.5 cm min−1. Like JA, transcripts of the JA synthesis gene LIPOXYGENASE2 (LOX2) and the jasmonate response gene JAZ10.3 also accumulated to higher levels in directly interconnected leaves than in indirectly connected leaves. JA accumulation in a lox2-1 mutant plant was initiated rapidly after wounding then slowed progressively compared with the wild type (WT). Despite this, JAZ10.3 expression in the two genotypes was similar. Free cyclopentenone jasmonate levels were similar in both resting WT and lox2-1. In contrast, bound cyclopentenone jasmonates (arabidopsides) were far lower in lox2-1 than in the WT. The major roles of LOX2 are to generate arabidopsides and the large levels of JA that accumulate proximal to the wound. LOX2 is not essential for some of the most rapid events elicited by wounding. PMID:19846562

  10. 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

  11. [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.

  12. [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

  13. [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

  14. [Characteristics of dry matter production and nitrogen accumulation in barley genotypes with high nitrogen utilization efficiency].

    PubMed

    Huang, Yi; Li, Ting-Xuan; Zhang, Xi-Zhou; Ji, Lin

    2014-07-01

    A pot experiment was conducted under low (125 mg x kg-1) and normal (250 mg x kg(-1)) nitrogen treatments. The nitrogen uptake and utilization efficiency of 22 barley cultivars were investigated, and the characteristics of dry matter production and nitrogen accumulation in barley were analyzed. The results showed that nitrogen uptake and utilization efficiency were different for barley under two nitrogen levels. The maximal values of grain yield, nitrogen utilization efficiency for grain and nitrogen harvest index were 2.87, 2.91 and 2.47 times as those of the lowest under the low nitrogen treatment. Grain yield and nitrogen utilization efficiency for grain and nitrogen harvest index of barley genotype with high nitrogen utilization efficiency were significantly greater than low nitrogen utilization efficiency, and the parameters of high nitrogen utilization efficiency genotype were 82.1%, 61.5% and 50.5% higher than low nitrogen utilization efficiency genotype under the low nitrogen treatment. Dry matter mass and nitrogen utilization of high nitrogen utilization efficiency was significantly higher than those of low nitrogen utilization efficiency. A peak of dry matter mass of high nitrogen utilization efficiency occurred during jointing to heading stage, while that of nitrogen accumulation appeared before jointing. Under the low nitrogen treatment, dry matter mass of DH61 and DH121+ was 34.4% and 38.3%, and nitrogen accumulation was 54. 8% and 58.0% higher than DH80, respectively. Dry matter mass and nitrogen accumulation seriously affected yield before jointing stage, and the contribution rates were 47.9% and 54.7% respectively under the low nitrogen treatment. The effect of dry matter and nitrogen accumulation on nitrogen utilization efficiency for grain was the largest during heading to mature stages, followed by sowing to jointing stages, with the contribution rate being 29.5% and 48.7%, 29.0% and 15.8%, respectively. In conclusion, barley genotype with high

  15. Do radial oxygen loss and external aeration affect iron plaque formation and arsenic accumulation and speciation in rice?

    PubMed

    Wu, Chuan; Ye, Zhihong; Li, Hui; Wu, Shengchun; Deng, Dan; Zhu, Yongguan; Wong, Minghung

    2012-05-01

    Hydroponic experiments were conducted to investigate the effect of radial oxygen loss (ROL) and external aeration on iron (Fe) plaque formation, and arsenic (As) accumulation and speciation in rice (Oryza sativa L.). The data showed that there were significant correlations between ROL and Fe concentrations in Fe plaque produced on different genotypes of rice. There were also significant differences in the amounts of Fe plaque formed between different genotypes in different positions of roots and under different aeration conditions (aerated, normal, and stagnant treatments). In aerated treatments, rice tended to have a higher Fe plaque formation than in a stagnant solution, with the greatest formation at the root tip decreasing with increasing distances away, in accordance with a trend of spatial ROL. Genotypes with higher rates of ROL induced higher degrees of Fe plaque formation. Plaques sequestered As on rice roots, with arsenate almost double that with arsenite, leading to decreased As accumulation in both roots and shoots. The major As species detected in roots and shoots was arsenite, ranging from 34 to 78% of the total As in the different treatments and genotypes. These results contribute to our understanding of genotypic differences in As uptake by rice and the mechanisms causing rice genotypes with higher ROL to show lower overall As accumulation.

  16. Do radial oxygen loss and external aeration affect iron plaque formation and arsenic accumulation and speciation in rice?

    PubMed Central

    Wu, Chuan; Ye, Zhihong; Li, Hui; Wu, Shengchun; Deng, Dan; Zhu, Yongguan; Wong, Minghung

    2012-01-01

    Hydroponic experiments were conducted to investigate the effect of radial oxygen loss (ROL) and external aeration on iron (Fe) plaque formation, and arsenic (As) accumulation and speciation in rice (Oryza sativa L.). The data showed that there were significant correlations between ROL and Fe concentrations in Fe plaque produced on different genotypes of rice. There were also significant differences in the amounts of Fe plaque formed between different genotypes in different positions of roots and under different aeration conditions (aerated, normal, and stagnant treatments). In aerated treatments, rice tended to have a higher Fe plaque formation than in a stagnant solution, with the greatest formation at the root tip decreasing with increasing distances away, in accordance with a trend of spatial ROL. Genotypes with higher rates of ROL induced higher degrees of Fe plaque formation. Plaques sequestered As on rice roots, with arsenate almost double that with arsenite, leading to decreased As accumulation in both roots and shoots. The major As species detected in roots and shoots was arsenite, ranging from 34 to 78% of the total As in the different treatments and genotypes. These results contribute to our understanding of genotypic differences in As uptake by rice and the mechanisms causing rice genotypes with higher ROL to show lower overall As accumulation. PMID:22345639

  17. Accumulation of recombinant cellobiohydrolase and endoglucanase in the leaves of mature transgenic sugar cane.

    PubMed

    Harrison, Mark D; Geijskes, Jason; Coleman, Heather D; Shand, Kylie; Kinkema, Mark; Palupe, Anthony; Hassall, Rachael; Sainz, Manuel; Lloyd, Robyn; Miles, Stacy; Dale, James L

    2011-10-01

    A major strategic goal in making ethanol from lignocellulosic biomass a cost-competitive liquid transport fuel is to reduce the cost of production of cellulolytic enzymes that hydrolyse lignocellulosic substrates to fermentable sugars. Current production systems for these enzymes, namely microbes, are not economic. One way to substantially reduce production costs is to express cellulolytic enzymes in plants at levels that are high enough to hydrolyse lignocellulosic biomass. Sugar cane fibre (bagasse) is the most promising lignocellulosic feedstock for conversion to ethanol in the tropics and subtropics. Cellulolytic enzyme production in sugar cane will have a substantial impact on the economics of lignocellulosic ethanol production from bagasse. We therefore generated transgenic sugar cane accumulating three cellulolytic enzymes, fungal cellobiohydrolase I (CBH I), CBH II and bacterial endoglucanase (EG), in leaves using the maize PepC promoter as an alternative to maize Ubi1 for controlling transgene expression. Different subcellular targeting signals were shown to have a substantial impact on the accumulation of these enzymes; the CBHs and EG accumulated to higher levels when fused to a vacuolar-sorting determinant than to an endoplasmic reticulum-retention signal, while EG was produced in the largest amounts when fused to a chloroplast-targeting signal. These results are the first demonstration of the expression and accumulation of recombinant CBH I, CBH II and EG in sugar cane and represent a significant first step towards the optimization of cellulolytic enzyme expression in sugar cane for the economic production of lignocellulosic ethanol.

  18. 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.

  19. Improved lipid accumulation by morphology engineering of oleaginous fungus Mortierella isabellina.

    PubMed

    Gao, Difeng; Zeng, Jijiao; Yu, Xiaochen; Dong, Tao; Chen, Shulin

    2014-09-01

    Oleaginous fungi capable of accumulating a considerable amount of lipids are promising sources for lipid-based biofuel production. The specific productivities of filamentous fungi in submerged fermentation are often correlated with morphological forms. However, the relationship between morphological development and lipid accumulation is not known. In this study, distinct morphological forms of oleaginous fungus Mortierella isabellina including pellets of different sizes, free dispersed mycelia, and broken hyphal fragments were developed by additions of different concentrations of magnesium silicate microparticles. Different morphological forms led to different levels of lipid accumulation as well as different spatial patterns of lipid distribution within pellets/mycelial aggregates. Significant higher lipid content (0.75 g lipid/g cell biomass) and lipid yield (0.18 g lipid/g glucose consumed) were achieved in free dispersed mycelia than in pellets. Moreover, extracellular metabolite analysis showed that production of undesirable by-product malate was repressed in free dispersed mycelium form. Unveiling the desired morphological form of M. isabellina for lipid accumulation provided insights into molecular mechanism of lipid biosynthesis linked with morphological development, as well as design and optimization of bioprocess to produce lipid-based biofuels.

  20. Microfluidic system for facilitated quantification of nanoparticle accumulation to cells under laminar flow.

    PubMed

    Kusunose, Jiro; Zhang, Hua; Gagnon, M Karen J; Pan, Tingrui; Simon, Scott I; Ferrara, Katherine W

    2013-01-01

    The identification of novel, synthetic targeting ligands to endothelial receptors has led to the rapid development of targeted nanoparticles for drug, gene and imaging probe delivery. Central to development and optimization are effective models for assessing particle binding in vitro. Here, we developed a simple and cost effective method to quantitatively assess nanoparticle accumulation under physiologically-relevant laminar flow. We designed reversibly vacuum-sealed PDMS microfluidic chambers compatible with 35 mm petri dishes, which deliver uniform or gradient shear stress. These chambers have sufficient surface area for facile cell collection for particle accumulation quantitation through FACS. We tested this model by synthesizing and flowing liposomes coated with APN (K (D) ~ 300 μM) and VCAM-1-targeting (K (D) ~ 30 μM) peptides over HUVEC. Particle binding significantly increased with ligand concentration (up to 6 mol%) and decreased with excess PEG. While the accumulation of particles with the lower affinity ligand decreased with shear, accumulation of those with the higher affinity ligand was highest in a low shear environment (2.4 dyne/cm(2)), as compared with greater shear or the absence of shear. We describe here a robust flow chamber model that is applied to optimize the properties of 100 nm liposomes targeted to inflamed endothelium. PMID:22855121

  1. Cooperation between interleukin-5 and the chemokine eotaxin to induce eosinophil accumulation in vivo

    PubMed Central

    1995-01-01

    Experiments were designed to study the effect of systemically administered IL-5 on local eosinophil accumulation induced by the intradermal injection of the chemokine eotaxin in the guinea pig. Intravenous interleukin-5 (IL-5) stimulated a rapid and dramatic increase in the numbers of accumulating eosinophils induced by i.d.- injected eotaxin and, for comparison, leukotriene B4. The numbers of locally accumulating eosinophils correlated directly with a rapid increase in circulating eosinophils: circulating eosinophil numbers were 13-fold higher 1 h after intravenous IL-5 (18.3 pmol/kg). This increase in circulating cells corresponded with a reduction in the number of displaceable eosinophils recovered after flushing out the femur bone marrow cavity. Intradermal IL-5, at the doses tested, did not induce significant eosinophil accumulation. We propose that these experiments simulate important early features of the tissue response to local allergen exposure in a sensitized individual, with eosinophil chemoattractant chemokines having an important local role in eosinophil recruitment from blood microvessels, and IL-5 facilitating this process by acting remotely as a hormone to stimulate the release into the circulation of a rapidly mobilizable pool of bone marrow eosinophils. This action of IL-5 would be complementary to the other established activities of IL-5 that operate over a longer time course. PMID:7561691

  2. Increased accumulation of magnetic nanoparticles by magnetizable implant materials for the treatment of implant-associated complications

    PubMed Central

    2013-01-01

    Background In orthopaedic surgery, accumulation of agents such as anti-infectives in the bone as target tissue is difficult. The use of magnetic nanoparticles (MNPs) as carriers principally enables their accumulation via an externally applied magnetic field. Magnetizable implants are principally able to increase the strength of an externally applied magnetic field to reach also deep-seated parts in the body. Therefore, the integration of bone-addressed therapeutics in MNPs and their accumulation at a magnetic orthopaedic implant could improve the treatment of implant related infections. In this study a martensitic steel platelet as implant placeholder was used to examine its accumulation and retention capacity of MNPs in an in vitro experimental set up considering different experimental frame conditions as magnet quantity and distance to each other, implant thickness and flow velocity. Results The magnetic field strength increased to approximately 112% when a martensitic stainless steel platelet was located between the magnet poles. Therewith a significantly higher amount of magnetic nanoparticles could be accumulated in the area of the platelet compared to the sole magnetic field. During flushing of the tube system mimicking the in vivo blood flow, the magnetized platelet was able to retain a higher amount of MNPs without an external magnetic field compared to the set up with no mounted platelet during flushing of the system. Generally, a higher flow velocity led to lower amounts of accumulated MNPs. A higher quantity of magnets and a lower distance between magnets led to a higher magnetic field strength. Albeit not significantly the magnetic field strength tended to increase with thicker platelets. Conclusion A martensitic steel platelet significantly improved the attachment of magnetic nanoparticles in an in vitro flow system and therewith indicates the potential of magnetic implant materials in orthopaedic surgery. The use of a remanent magnetic implant

  3. Microarchitecture Influences Microdamage Accumulation in Human Vertebral Trabecular Bone

    PubMed Central

    Arlot, Monique E; Burt-Pichat, Brigitte; Roux, Jean-Paul; Vashishth, Deepak; Bouxsein, Mary L; Delmas, Pierre D

    2008-01-01

    It has been suggested that accumulation of microdamage with age contributes to skeletal fragility. However, data on the age-related increase in microdamage and the association between microdamage and trabecular microarchitecture in human vertebral cancellous bone are limited. We quantified microdamage in cancellous bone from human lumbar (L2) vertebral bodies obtained from 23 donors 54–93 yr of age (8 men and 15 women). Damage was measured using histologic techniques of sequential labeling with chelating agents and was related to 3D microarchitecture, as assessed by high-resolution μCT. There were no significant differences between sexes, although women tended to have a higher microcrack density (Cr.Dn) than men. Cr.Dn increased exponentially with age (r = 0.65, p < 0.001) and was correlated with bone volume fraction (BV/TV; r = −0.55; p < 0.01), trabecular number (Tb.N; r = −0.56 p = 0.008), structure model index (SMI; r = 0.59; p = 0.005), and trabecular separation (Tb.Sp; r = 0.59; p < 0.009). All architecture parameters were strongly correlated with each other and with BV/TV. Stepwise regression showed that SMI was the best predictor of microdamage, explaining 35% of the variance in Cr.Dn and 20% of the variance in diffuse damage accumulation. In addition, microcrack length was significantly greater in the highest versus lowest tertiles of SMI. In conclusion, in human vertebral cancellous bone, microdamage increases with age and is associated with low BV/TV and a rod-like trabecular architecture. PMID:18518771

  4. Accumulated p53 protein and UVA protection level of sunscreens.

    PubMed

    Seité, S; Moyal, D; Verdier, M P; Hourseau, C; Fourtanier, A

    2000-02-01

    Nuclear p53 expression is a sensitive parameter for the detection of ultraviolet (UV)-induced skin damage, and it has been used as an endpoint to evaluate the effectiveness of sunscreens. In this study, we compared the protection provided by two sunscreens having identical sun protection factors (SPF) but different UVA protection factors (UVA-PF) measured by the persistent pigment darkening method (PPD). The SPF of the sunscreens was 7 and the UVA-PF were respectively 7 and 3. Nuclear p53 protein was quantified in human skin biopsies treated with sunscreens and exposed 8 times to 5 MED of solar simulated radiation (SSR). The results showed that both sunscreens offered only partial protection against the increased expression of nuclear p53 protein induced by repetitive SSR exposures. However, a significantly lower level of p53-positive cells was found in areas protected with the sunscreen having the higher UVA-PF compared to the other sunscreen protected areas. In order to verify whether the difference in efficacy of these products was due to the difference in UVA absorption capacity, we quantified epidermal p53 protein accumulation after 8 exposures to either UVA (320-400 nm) or UVA1 (340-400 nm). We showed that as with SSR, repetitive exposures to 12.5 and 25 J/cm2 of UVA or UVA1 induced a significant increase in p53-positive cells in the human epidermis. These results confirmed that SPF determined on the basis of an acute erythemal reaction does not predict the level of protection against cumulative damage. They also showed that the protection provided by two sunscreens with different UVA protection factors is different (based on nuclear p53 protein accumulation), and that the PPD method can distinguish varying levels of sunscreen efficacy against UVA-induced cell damage. PMID:10721857

  5. Accumulation of mercury in edible macrofungi: influence of some factors.

    PubMed

    Alonso, J; Salgado, M J; García, M A; Melgar, M J

    2000-02-01

    The levels of mercury in terrestrial ecosystems are generally very low, but the strong accumulation in some species of macrofungi is an exception from this rule. Mercury contents of 41 samples of edible mushrooms fruiting bodies representing eight species (six wild and two cultivated) were determined by an anodic stripping voltammetric technique (ASV) using a gold disc as the working electrode. Wild fungi were collected in unpolluted and polluted areas in the Province of Lugo (NW Spain). Influence of some factors (ecology, species, traffic pollution, and morphological portion) and the importance of mushrooms as a dietary source of mercury have been studied. Wild saprophytic species showed higher levels (ppm DW) than mycorrhizals species, with the exception of Boletus pinicola. There were significant differences according to the species analyzed (p < 0.001), the highest average content of mercury was found in Boletus pinicola (7.37 ppm DW), and the range was 0.35-33.07 ppm DW for hymenophore and 0.18-20.30 ppm DW for the rest of the fruit body. The cultivated species accumulated lower than wild species because the mean life is shorter. The traffic pollution factor did not show significant differences, so mushrooms are not realiable bioindicators of traffic pollution by mercury. Hymenophore was always the morphological portion that contained the highest mercury levels (p < 0.05), and the mean ratio of hymenophore/rest of the fruit body was 2.13. The mercury concentrations were compared to literature data and levels set by legislation, and the contribution of mushrooms to the weekly intake of mercury per person was evaluated. The possible health risk for people is pointed out. PMID:10629276

  6. P accumulation and physiological responses to different high P regimes in Polygonum hydropiper for understanding a P-phytoremediation strategy.

    PubMed

    Ye, Daihua; Li, Tingxuan; Liu, Dan; Zhang, Xizhou; Zheng, Zicheng

    2015-01-01

    Phosphorus (P) accumulators used for phytoremediation vary in their potential to acquire P from different high P regimes. Growth and P accumulation in Polygonum hydropiper were both dependent on an increasing level of IHP (1-8 mM P) and on a prolonged growth period (3-9 weeks), and those of the mining ecotype (ME) were higher than the non-mining ecotype (NME). Biomass increments in root, stem, and leaf of both ecotypes were significantly greater in IHP relative to other organic P (Po) sources (G1P, AMP, ATP), but lower than those in inorganic P (Pi) treatment (KH2PO4). P accumulation in the ME exceeded the NME from different P regimes. The ME demonstrated higher root activity compared to the NME grown in various P sources. Acid phosphatase (Apase) and phytase activities in root extracts of both ecotypes grown in IHP were comparable to that in Pi, or even higher in IHP. Higher secreted Apase and phytase activities were detected in the ME treated with different P sources relative to the NME. Therefore, the ME demonstrates higher P-uptake efficiency and it is a potential material for phytoextraction from P contaminated areas, irrespective of Pi or Po contamination. PMID:26648137

  7. P accumulation and physiological responses to different high P regimes in Polygonum hydropiper for understanding a P-phytoremediation strategy

    PubMed Central

    Ye, Daihua; Li, Tingxuan; Liu, Dan; Zhang, Xizhou; Zheng, Zicheng

    2015-01-01

    Phosphorus (P) accumulators used for phytoremediation vary in their potential to acquire P from different high P regimes. Growth and P accumulation in Polygonum hydropiper were both dependent on an increasing level of IHP (1–8 mM P) and on a prolonged growth period (3-9 weeks), and those of the mining ecotype (ME) were higher than the non-mining ecotype (NME). Biomass increments in root, stem, and leaf of both ecotypes were significantly greater in IHP relative to other organic P (Po) sources (G1P, AMP, ATP), but lower than those in inorganic P (Pi) treatment (KH2PO4). P accumulation in the ME exceeded the NME from different P regimes. The ME demonstrated higher root activity compared to the NME grown in various P sources. Acid phosphatase (Apase) and phytase activities in root extracts of both ecotypes grown in IHP were comparable to that in Pi, or even higher in IHP. Higher secreted Apase and phytase activities were detected in the ME treated with different P sources relative to the NME. Therefore, the ME demonstrates higher P-uptake efficiency and it is a potential material for phytoextraction from P contaminated areas, irrespective of Pi or Po contamination. PMID:26648137

  8. P accumulation and physiological responses to different high P regimes in Polygonum hydropiper for understanding a P-phytoremediation strategy.

    PubMed

    Ye, Daihua; Li, Tingxuan; Liu, Dan; Zhang, Xizhou; Zheng, Zicheng

    2015-12-09

    Phosphorus (P) accumulators used for phytoremediation vary in their potential to acquire P from different high P regimes. Growth and P accumulation in Polygonum hydropiper were both dependent on an increasing level of IHP (1-8 mM P) and on a prolonged growth period (3-9 weeks), and those of the mining ecotype (ME) were higher than the non-mining ecotype (NME). Biomass increments in root, stem, and leaf of both ecotypes were significantly greater in IHP relative to other organic P (Po) sources (G1P, AMP, ATP), but lower than those in inorganic P (Pi) treatment (KH2PO4). P accumulation in the ME exceeded the NME from different P regimes. The ME demonstrated higher root activity compared to the NME grown in various P sources. Acid phosphatase (Apase) and phytase activities in root extracts of both ecotypes grown in IHP were comparable to that in Pi, or even higher in IHP. Higher secreted Apase and phytase activities were detected in the ME treated with different P sources relative to the NME. Therefore, the ME demonstrates higher P-uptake efficiency and it is a potential material for phytoextraction from P contaminated areas, irrespective of Pi or Po contamination.

  9. Does power indicate capacity? 30-s Wingate anaerobic test vs. maximal accumulated O2 deficit.

    PubMed

    Minahan, C; Chia, M; Inbar, O

    2007-10-01

    The purpose of this study was to evaluate the relationship between anaerobic power and capacity. Seven men and seven women performed a 30-s Wingate Anaerobic Test on a cycle ergometer to determine peak power, mean power, and the fatigue index. Subjects also cycled at a work rate predicted to elicit 120 % of peak oxygen uptake to exhaustion to determine the maximal accumulated O (2) deficit. Peak power and the maximal accumulated O (2) deficit were significantly correlated (r = 0.782, p = 0.001). However, when the absolute difference in exercise values between groups (men and women) was held constant using a partial correlation, the relationship diminished (r = 0.531, p = 0.062). In contrast, we observed a significant correlation between fatigue index and the maximal accumulated O (2) deficit when controlling for gender (r = - 0.597, p = 0.024) and the relationship remained significant when values were expressed relative to active muscle mass. A higher anaerobic power does not indicate a greater anaerobic capacity. Furthermore, we suggest that the ability to maintain power output during a 30-s cycle sprint is related to anaerobic capacity.

  10. [Effects of sprinkler irrigation on the plant nitrogen accumulation and translocation and kernel protein content of winter wheat].

    PubMed

    Yao, Su-mei; Kang, Yue-hu; Ru, Zhen-gang; Liu, Ming-jiu; Yang, Wen-ping; Li, Gan

    2013-08-01

    Taking wheat cultivar Bainong AK58 as test material, a field experiment was conducted to study the plant nitrogen accumulation and translocation and kernel protein content of winter wheat under sprinkler irrigation and surface irrigation, aimed to understand the differences in the nitrogen metabolism characteristics of winter wheat under different irrigation regimes. At booting stage, no significant difference was observed in the total amount of plant nitrogen accumulation between sprinkler irrigation and surface irrigation; while from booting stage to maturing stage, the total amount of plant nitrogen accumulation under sprinkler irrigation was significantly higher. Under sprinkler irrigation, the translocation amount and contribution rate of the nitrogen stored in leaf, glume, stem and sheath at pre-anthesis to the kernel increased, while the contribution rate of the assimilated nitrogen after anthesis to the kernel nitrogen declined. Both the relative protein content and the total protein yield in the kernel increased significantly under sprinkler irrigation. In conclusion, sprinkler irrigation could significantly regulate the nitrogen translocation and kernel protein accumulation of winter wheat. PMID:24380339

  11. Relationship of trehalose accumulation with ethanol fermentation in industrial Saccharomyces cerevisiae yeast strains.

    PubMed

    Wang, Pin-Mei; Zheng, Dao-Qiong; Chi, Xiao-Qin; Li, Ou; Qian, Chao-Dong; Liu, Tian-Zhe; Zhang, Xiao-Yang; Du, Feng-Guang; Sun, Pei-Yong; Qu, Ai-Min; Wu, Xue-Chang

    2014-01-01

    The protective effect and the mechanisms of trehalose accumulation in industrial Saccharomyces cerevisiae strains were investigated during ethanol fermentation. The engineered strains with more intercellular trehalose achieved significantly higher fermentation rates and ethanol yields than their wild strain ZS during very high gravity (VHG) fermentation, while their performances were not different during regular fermentation. The VHG fermentation performances of these strains were consistent with their growth capacity under osmotic stress and ethanol stress, the key stress factors during VHG fermentation. These results suggest that trehalose accumulation is more important for VHG fermentation of industrial yeast strains than regular one. The differences in membrane integrity and antioxidative capacity of these strains indicated the possible mechanisms of trehalose as a protectant under VHG condition. Therefore, trehalose metabolic engineering may be a useful strategy for improving the VHG fermentation performance of industrial yeast strains.

  12. Trends and drivers of debris accumulation on Maui shorelines: Implications for local mitigation strategies.

    PubMed

    Blickley, Lauren C; Currie, Jens J; Kaufman, Gregory D

    2016-04-15

    Marine debris, particularly plastic, is an identified concern for coastal areas and is known to accumulate in large quantities in the North Pacific. Here we present results from the first study to quantify and compare the types and amounts of marine debris on Maui shorelines. Surveys were conducted monthly between May 2013 and December 2014, with additional daily surveys conducted on Maui's north shore during January 2015. Debris accumulation rates, loads, and sources varied between sites, with plastics being the most prevalent type of debris at all sites. Large debris loads on windward shores were attributed to the influence of the North Pacific Subtropical Gyre and northerly trade winds. Daily surveys resulted in a significantly higher rate of debris deposition than monthly surveys. The efficacy of local policy in debris mitigation showed promise, but was dependent upon the level of enforcement and consumer responsibility. PMID:26926778

  13. Facilitation of Rice Stripe Virus Accumulation in the Insect Vector by Himetobi P Virus VP1

    PubMed Central

    Li, Shuo; Ge, Shangshu; Wang, Xi; Sun, Lijuan; Liu, Zewen; Zhou, Yijun

    2015-01-01

    The small brown planthopper (SBPH) is the main vector for rice stripe virus (RSV), which causes serious rice stripe disease in East Asia. To characterize the virus-vector interactions, the SBPH cDNA library was screened with RSV ribonucleoprotein (RNP) as bait using a GAL4-based yeast two-hybrid system. The interaction between RSV-RNP and the Himetobi P virus (HiPV, an insect picorna-like virus) VP1 protein was identified. The relationships between HiPV and RSV in SBPH were further investigated, and the results showed that the titer of RSV was commonly higher in single insect that exhibited more VP1 expression. After the VP1 gene was repressed by RNA silencing, the accumulation of RSV decreased significantly in the insect, whereas the virus acquisition ability of SBPH was unaffected, which suggests that HiPV VP1 potentially facilitates the accumulation of RSV in SBPH. PMID:25807055

  14. Fluoride accumulation in different earthworm species near an industrial emission source in southern Germany

    SciTech Connect

    Vogel, J.; Ottow, J.C.G. )

    1991-10-01

    The information on fluorides (F)-pollution of soil invertebrates is sparse and only a few recent publications deal with F accumulation in some taxonomic groups of soil fauna. Earthworms in particular become the focus of soil-soil fauna interactions in F-polluted sites, even more so since a significant relationship between soil pollution and F load in earthworms was observed. Earthworms coat their burrowings and this may be a mechanism of F-dissemination and subsoil contamination. Evidence is growing that fluorides pass through food chains. Earthworms as the preferred prey of a wide range of animals are therefore in the center of interest as a possible way of F-bioaccumulation in higher trophic levels. For a risk assessment of F-pollution and pathways of F through organisms and ecosystems, detailed knowledge of F-accumulation in soil fauna, and in earthworms in particular is required.

  15. Trends and drivers of debris accumulation on Maui shorelines: Implications for local mitigation strategies.

    PubMed

    Blickley, Lauren C; Currie, Jens J; Kaufman, Gregory D

    2016-04-15

    Marine debris, particularly plastic, is an identified concern for coastal areas and is known to accumulate in large quantities in the North Pacific. Here we present results from the first study to quantify and compare the types and amounts of marine debris on Maui shorelines. Surveys were conducted monthly between May 2013 and December 2014, with additional daily surveys conducted on Maui's north shore during January 2015. Debris accumulation rates, loads, and sources varied between sites, with plastics being the most prevalent type of debris at all sites. Large debris loads on windward shores were attributed to the influence of the North Pacific Subtropical Gyre and northerly trade winds. Daily surveys resulted in a significantly higher rate of debris deposition than monthly surveys. The efficacy of local policy in debris mitigation showed promise, but was dependent upon the level of enforcement and consumer responsibility.

  16. Relationship of trehalose accumulation with ethanol fermentation in industrial Saccharomyces cerevisiae yeast strains.

    PubMed

    Wang, Pin-Mei; Zheng, Dao-Qiong; Chi, Xiao-Qin; Li, Ou; Qian, Chao-Dong; Liu, Tian-Zhe; Zhang, Xiao-Yang; Du, Feng-Guang; Sun, Pei-Yong; Qu, Ai-Min; Wu, Xue-Chang

    2014-01-01

    The protective effect and the mechanisms of trehalose accumulation in industrial Saccharomyces cerevisiae strains were investigated during ethanol fermentation. The engineered strains with more intercellular trehalose achieved significantly higher fermentation rates and ethanol yields than their wild strain ZS during very high gravity (VHG) fermentation, while their performances were not different during regular fermentation. The VHG fermentation performances of these strains were consistent with their growth capacity under osmotic stress and ethanol stress, the key stress factors during VHG fermentation. These results suggest that trehalose accumulation is more important for VHG fermentation of industrial yeast strains than regular one. The differences in membrane integrity and antioxidative capacity of these strains indicated the possible mechanisms of trehalose as a protectant under VHG condition. Therefore, trehalose metabolic engineering may be a useful strategy for improving the VHG fermentation performance of industrial yeast strains. PMID:24316480

  17. [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

  18. Effects of phosphate and thiosulphate on arsenic accumulation in the species Brassica juncea.

    PubMed

    Grifoni, Martina; Schiavon, Michela; Pezzarossa, Beatrice; Petruzzelli, Gianniantonio; Malagoli, Mario

    2015-02-01

    Arsenic (As) is recognized as a toxic pollutant in soils of many countries. Since phosphorus (P) and sulphur (S) can influence arsenic mobility and bioavailability, as well as the plant tolerance to As, phytoremediation techniques employed to clean-up As-contaminated areas should consider the interaction between As and these two nutrients. In this study, the bioavailability and accumulation of arsenate in the species Brassica juncea were compared between soil system and hydroponics in relation to P and S concentration of the growth substrate. In one case, plants were grown in pots filled with soil containing 878 mg As kg(-1). The addition of P to soil resulted in increased As desorption and significantly higher As accumulation in plants, with no effect on growth. The absence of toxic effects on plants was likely due to high S in soil, which could efficiently mitigate metal toxicity. In the hydroponic experiment, plants were grown with different combinations of As (0 or 100 μM) and P (56 or 112 μM). S at 400 μM was also added to the nutrient solution of control (-As) and As-treated plants, either individually or in combination with P. The addition of P reduced As uptake by plants, while high S resulted in higher As accumulation and lower P content. These results suggest that S can influence the interaction between P and As for the uptake by plants. The combined increase of P and S in the nutrient solution did not lead to higher accumulation of As, but enhanced As translocation from the root to the shoot. This aspect is of relevance for the phytoremediation of As-contaminated sites. PMID:24677062

  19. 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

  20. CONCEPTUAL MODEL FOR ORIGIN OF ABNORMALLY PRESSURED GAS ACCUMULATIONS IN LOW-PERMEABILITY RESERVOIRS.

    USGS Publications Warehouse

    Law, B.E.; Dickinson, W.W.

    1985-01-01

    The paper suggests that overpressured and underpressured gas accumulations of this type have a common origin. In basins containing overpressured gas accumulations, rates of thermogenic gas accumulation exceed gas loss, causing fluid (gas) pressure to rise above the regional hydrostatic pressure. Free water in the larger pores is forced out of the gas generation zone into overlying and updip, normally pressured, water-bearing rocks. While other diagenetic processes continue, a pore network with very low permeability develops. As a result, gas accumulates in these low-permeability reservoirs at rates higher than it is lost. In basins containing underpressured gas accumulations, rates of gas generation and accumulation are less than gas loss. The basin-center gas accumulation persists, but because of changes in the basin dynamics, the overpressured accumulation evolves into an underpressured system.

  1. 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

  2. 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

  3. Relationship between in vitro binding activity and in vivo tumor accumulation of radiolabeled monoclonal antibodies

    SciTech Connect

    Sakahara, H.; Endo, K.; Koizumi, M.; Nakashima, T.; Kunimatsu, M.; Watanabe, Y.; Kawamura, Y.; Nakamura, T.; Tanaka, H.; Kotoura, Y.

    1988-02-01

    The relationship between in vitro cell binding and in vivo tumor accumulation of radiolabeled antibodies was studied using /sup 125/I- and /sup 111/In-labeled monoclonal antibodies to human osteosarcoma, and a human osteosarcoma xenograft (KT005) in nude mice. Three monoclonal antibodies--OST6, OST7, and OST15--raised against human osteosarcoma recognize the same antigen molecule. Although the binding of both /sup 125/I- and /sup 111/In-labeled OST6 to KT005 cells was higher than that of radiolabeled OST7 in vitro, /sup 125/I-labeled OST6 showed a faster clearance from the circulation and a lower accumulation in the transplanted tumor than /sup 125/I-labeled OST7. In contrast to the radioiodinated antibodies, the in vivo tumor accumulation of /sup 111/In-labeled OST6 was higher, although not significantly, than that of /sup 111/In-labeled OST7. OST15 showed the lowest binding in vitro, and its in vivo tumor localization was also lower than the others. The discrepancy in tumor uptake between OST6 and OST7 labeled with either /sup 125/I or /sup 111/In may have been a result of differing blood clearance. These results suggest that binding studies can be used to exclude from in vivo use those antibodies which show very poor binding in vitro, while in vivo serum clearance may be a better test for choosing antibodies with similar binding.

  4. 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

  5. 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.

  6. Chromoplast biogenesis and carotenoid accumulation.

    PubMed

    Li, Li; Yuan, Hui

    2013-11-15

    Chromoplasts are special organelles that possess superior ability to synthesize and store massive amounts of carotenoids. They are responsible for the distinctive colors found in fruits, flowers, and roots. Chromoplasts exhibit various morphologies and are derived from either pre-existing chloroplasts or other non-photosynthetic plastids such as proplastids, leucoplasts or amyloplasts. While little is known about the molecular mechanisms underlying chromoplast biogenesis, research progress along with proteomics study of chromoplast proteomes signifies various processes and factors important for chromoplast differentiation and development. Chromoplasts act as a metabolic sink that enables great biosynthesis and high storage capacity of carotenoids. The formation of chromoplasts enhances carotenoid metabolic sink strength and controls carotenoid accumulation in plants. The objective of this review is to provide an integrated view on our understanding of chromoplast biogenesis and carotenoid accumulation in plants.

  7. 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

  8. Biomass carbon accumulation by Japan's forests from 1947 to 1995

    NASA Astrophysics Data System (ADS)

    Fang, Jingyun; Oikawa, Takehisa; Kato, Tomomichi; Mo, Wenhong; Wang, Zhiheng

    2005-06-01

    Forest ecosystems in the Northern Hemisphere function as carbon (C) sinks for atmospheric carbon dioxide; however, the magnitude, location, and cause of the sinks remain uncertain. A number of field measurements of forest biomass and systematic national forest inventories in Japan make it possible to quantify the C sinks and their distribution. Allometric relationships between forest biomass and stem volume were obtained for the major forest types in Japan from 945 sets of direct field measurements across the country. These relationships were used to estimate the changes in C accumulations of aboveground biomass and total living biomass from 1947 to 1995 from the national forest inventories of 1947, 1956, 1961, 1965, 1975, 1980, 1985, 1990, and 1995. The results showed that the C accumulations have significantly increased during the last 50 years. The C density (C stock per hectare) and total C stock of aboveground biomass increased from 27.6 Mg C/ha and 611.7 Tg C in 1947 to 43.2 Mg C/ha and 1027.7 Tg C in 1995, respectively, and those of total living biomass increased from 33.9 Mg C/ha and 751.8 Tg C in 1947 to 53.6 Mg C/ha and 1274.8 Tg C in 1995. These increases were remarkable during 1976-1995, with a net increase of 5.6 Mg C/ha and 369 Tg C for the C density and total living biomass. These results suggest that Japan's forest vegetation is a significant C sink. In the past 20 years, living vegetation has sequestered 18.5 Tg C annually, 14.6 Tg C of which was accumulated in aboveground biomass. The total C sink for the whole forest sector (including nonliving biomass) of Japan was estimated as 36 Tg C/yr if using the net change ratio of nonliving biomass C to living biomass C derived from the United States and Europe. On the basis of average C sink per hectare, Japan's forests have a higher sequestration rate (0.77 Mg C ha-1 yr-1) than the average of the other northern countries (0.14-0.19 Mg C ha-1 yr-1). The expansion and regrowth of planted forests are two

  9. 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.

  10. 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.

  11. Metal and metalloid levels and bio-accumulation characteristics in soil, sediment, land plants and hippopotami (Hippopotamus amphibius L) from the South Luangwa National Park, Zambia.

    PubMed

    Nakayama, Shouta M M; Ikenaka, Yoshinori; Muzandu, Kaampwe; Choongo, Kennedy; M'kandawire, Ethel; Yasuda, Jun; Ishizuka, Mayumi

    2012-06-01

    Hippopotami (Hippopotamus amphibius L) are large semi-aquatic mammals that can be exposed to metals and metalloid from both terrestrial and aquatic environments. Therefore, knowledge of metal and metalloid accumulation characteristics in hippopotami living in the national park is important from ecotoxicological point of view. Levels of toxic metals (Cd, Pb and Hg) and metalloid (As) in hippopotami liver from the South Luangwa National Park in Zambia were far lower compared to the established values of toxic levels in cattle. No temporal variations of metal levels in hippopotami were observed, probably because of good management condition and the lack of anthropogenic activities around the national park. However, hippopotami liver accumulated significantly higher concentrations of Hg compared to soil, sediment and their food (plants), most likely due to a process of biomagnification throughout a trophic chain. Moreover, hippopotami liver and land plants showed significantly higher Cd levels than those of soil. These results strongly suggest that hippopotami liver accumulate higher levels of these metals if surrounding environment is contaminated. Levels of Cr and Ni in hippopotami liver were higher compared to other toxic metals. Since this is the first report to show the Cr and Ni levels and bio-accumulation characteristics of Hg and Cd in hippopotami, we concluded that continuous monitoring and evaluation of toxic effects of these metals on hippopotami should be conducted.

  12. Metal and metalloid levels and bio-accumulation characteristics in soil, sediment, land plants and hippopotami (Hippopotamus amphibius L) from the South Luangwa National Park, Zambia.

    PubMed

    Nakayama, Shouta M M; Ikenaka, Yoshinori; Muzandu, Kaampwe; Choongo, Kennedy; M'kandawire, Ethel; Yasuda, Jun; Ishizuka, Mayumi

    2012-06-01

    Hippopotami (Hippopotamus amphibius L) are large semi-aquatic mammals that can be exposed to metals and metalloid from both terrestrial and aquatic environments. Therefore, knowledge of metal and metalloid accumulation characteristics in hippopotami living in the national park is important from ecotoxicological point of view. Levels of toxic metals (Cd, Pb and Hg) and metalloid (As) in hippopotami liver from the South Luangwa National Park in Zambia were far lower compared to the established values of toxic levels in cattle. No temporal variations of metal levels in hippopotami were observed, probably because of good management condition and the lack of anthropogenic activities around the national park. However, hippopotami liver accumulated significantly higher concentrations of Hg compared to soil, sediment and their food (plants), most likely due to a process of biomagnification throughout a trophic chain. Moreover, hippopotami liver and land plants showed significantly higher Cd levels than those of soil. These results strongly suggest that hippopotami liver accumulate higher levels of these metals if surrounding environment is contaminated. Levels of Cr and Ni in hippopotami liver were higher compared to other toxic metals. Since this is the first report to show the Cr and Ni levels and bio-accumulation characteristics of Hg and Cd in hippopotami, we concluded that continuous monitoring and evaluation of toxic effects of these metals on hippopotami should be conducted. PMID:22521811

  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. Patterns of accumulation and flow of ice in the mid-latitudes of Mars during the Amazonian

    NASA Astrophysics Data System (ADS)

    Dickson, James L.; Head, James W.; Fassett, Caleb I.

    2012-06-01

    Evidence has accumulated that non-polar portions of Mars have undergone significant periods of glaciation during the Amazonian Period. This evidence includes tropical mountain glacial deposits, lobate debris aprons, lineated valley fill, concentric crater fill, pedestal craters, and related landforms, some of which suggest that ice thicknesses exceeded a kilometer in many places. In some places, several lines of evidence suggest that ice is still preserved today in the form of relict debris-coved glaciers. The vast majority of deposit morphologies are analogous to those seen in cold-based glacial deposits on Earth, suggesting that little melting has taken place. Although these features have been broadly recognized, and their modes of ice accumulation and flow analyzed at several scales, they have not been analyzed and well-characterized globally despite their significance for understanding the evolution of the martian climate. A major outstanding question is the global extent of accumulation and flow of ice during periods of non-polar glaciation: As a mechanism to address this question, we outline two end-member scenarios to provide a framework for further discussion and analysis: (1) ice accumulation was mainly focused within individual craters and valleys and flow was largely local to regional in scale, and (2) ice accumulation was dominated by global latitudinal scale cold-based ice sheets, similar in scale to the Laurentide continental ice sheets on Earth. In order to assess these end members, we conducted a survey of ice-related features seen in Context Camera (CTX) images in each hemisphere and mapped evidence for flow directions within well-preserved craters in an effort to decipher orientation preferences that could help distinguish between these two hypotheses: regional/hemispheric glaciation or local accumulation and flow. These new crater data reveal a latitudinal-dependence on flow direction: at low latitudes in each hemisphere (<40-45°) cold, pole

  15. Solute accumulation of chestnut oak and dogwood leaves in response to throughfall manipulation of an upland oak forest.

    PubMed

    Gebre, G Michael; Tschaplinski, Timothy J

    2002-03-01

    To determine the biochemical basis of osmotic adjustment, seasonal and treatment differences in foliar water- soluble organic solutes and inorganic ions were investigated for two hardwood species that exhibited osmotic adjustment in a Throughfall Displacement Experiment at the Walker Branch Watershed near Oak Ridge, Tennessee. Leaf samples of overstory and understory chestnut oak (Quercus prinus L.) and understory dogwood (Cornus florida L.) were collected during the 1994 (wet) and 1995 (dry) growing seasons from each of three treatments: dry (-33% throughfall), ambient (control) and wet (+33% throughfall). Foliar soluble carbohydrates and organic acids were measured by gas chromatography-mass spectrometry. During May 1994, when the demand for sucrose was greatest, dogwood accumulated small amounts of glucose, quinic acid and Mg2+, offsetting a decline in nitrate concentration. As the mild drought continued and tree growth slowed, there was a significant accumulation of sucrose in dogwood in the dry treatment in June, and a trend toward increased K+. In overstory chestnut oak in the dry treatment over the same period, there were significant accumulations of fructose, glucose and K+, and a trend toward increased quinic acid accumulation. Sucrose did not become a key osmotically active compound in chestnut oak until August 1994. In 1995, with the exception of understory chestnut oak, there was no accumulation of K+ in either species. During the severe drought of 1995, monosaccharides, particularly glucose and fructose, accounted for most of the osmotic adjustment in both species. Among solutes, glucose constituted the largest accumulation in dogwood in the dry treatment in August 1995, followed by fructose and sucrose. There was only a moderate increase in solutes in chestnut oak trees in 1995, with fructose and glucose constituting over 50% of the predicted solute accumulation in July. Both species accumulated a wider array of solutes during the dry year than during

  16. [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

  17. 17 CFR 256.190 - Accumulated deferred income taxes.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... UTILITY HOLDING COMPANY ACT OF 1935 4. Deferred Debits § 256.190 Accumulated deferred income taxes. (a) This account shall be debited and account 411, Provision for deferred income taxes—credit, or account... which income taxes payable for the year are higher because of the inclusion of certain items in...

  18. 17 CFR 256.190 - Accumulated deferred income taxes.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... UTILITY HOLDING COMPANY ACT OF 1935 4. Deferred Debits § 256.190 Accumulated deferred income taxes. (a) This account shall be debited and account 411, Provision for deferred income taxes—credit, or account... which income taxes payable for the year are higher because of the inclusion of certain items in...

  19. Antiproton Accumulator in the Main Injector era (2)

    SciTech Connect

    Visnjic, V.

    1992-12-01

    By adding a single quadrupole per sextant in the Antiproton Accumulator it is possible to obtain a lattice well suited for higher bandwidth stochastic cooling systems such as those anticipated for the Main Injector era. The lattice proposed here has excellent properties concerning both the lattice functions and the stochastic cooling parameters.

  20. Simulating inbreeding depression through the mutation accumulation theory

    NASA Astrophysics Data System (ADS)

    Sousa, A. O.; de Oliveira, S. Moss; Bernardes, Américo T.

    2000-04-01

    Using the Penna model for biological aging, which is based on the mutation accumulation theory, we show that the number of homozygous loci corresponding to deleterious mutations is higher in small populations than in large ones. This decrease of heterozygosity may drive small populations to extinction even when no drastic change of the environment occurs.

  1. Role of sooty mold fungi in accumulation of fine-particle-associated PAHs and metals on deciduous leaves.

    PubMed

    Jouraeva, Venera A; Johnson, David L; Hassett, John P; Nowak, David J; Shipunova, Natalia A; Barbarossa, Dana

    2006-11-01

    The focus of this research was on elucidation of the role of deciduous tree ecosystems in accumulation of fine-particle-associated polycyclic aromatic hydrocarbons (PAHs) and heavy metals on leaves of deciduous trees. The studied species were Tilia x euchlora (frequently infested by sooty mold fungi) and Pyrus calleryana (unaffected by sooty mold fungi). The selected species have similar leaf morphology and were exposed to identical environmental conditions. Intra-species comparison showed that moldy linden leaves accumulate significantly higher amounts of PAHs and metals than unaffected linden leaves. Inter-species comparison revealed that in the absence of sooty mold fungi, physico-chemical properties of epicuticular waxes, rather than the amounts of waxes, might play an important role in accumulation of particulate matter on leaves. The accumulation and/or degradation of a number of high-molecular-weight (HMW) PAHs on leaves was temperature dependent. The results show that the presence of sooty mold fungi on deciduous leaves alters either the accumulation modes and/or degradation pathways of PAHs on deciduous leaves.

  2. Mouse SIRT3 Attenuates Hypertrophy-Related Lipid Accumulation in the Heart through the Deacetylation of LCAD

    PubMed Central

    Chen, Tongshuai; Liu, Junni; Li, Na; Wang, Shujian; Liu, Hui; Li, Jingyuan; Zhang, Yun; Bu, Peili

    2015-01-01

    Cardiac hypertrophy is an adaptive response to pressure, volume stress, and loss of contractile mass from prior infarction. Metabolic changes in cardiac hypertrophy include suppression of fatty acid oxidation and enhancement of glucose utilization, which could result in lipid accumulation in the heart. SIRT3, a mitochondrial NAD+-dependent deacetylase, has been demonstrated to play a crucial role in controlling the acetylation status of many enzymes participating in energy metabolism. However, the role of SIRT3 in the pathogenesis of hypertrophy-related lipid accumulation remains unclear. In this study, hypertrophy-related lipid accumulation was investigated using a mouse cardiac hypertrophy model induced by transverse aortic constriction (TAC). We showed that mice developed heart failure six weeks after TAC. Furthermore, abnormal lipid accumulation and decreased palmitate oxidation rates were observed in the hypertrophic hearts, and these changes were particularly significant in SIRT3-KO mice. We also demonstrated that the short form of SIRT3 was downregulated in wild-type (WT) hypertrophic hearts and that this change was accompanied by a higher acetylation level of long-chain acyl CoA dehydrogenase (LCAD), which is a key enzyme participating in fatty acid oxidation. In addition, SIRT3 may play an essential role in attenuating lipid accumulation in the heart through the deacetylation of LCAD. PMID:25748450

  3. Influence of the Environmental Factors on the Accumulation of the Bioactive Ingredients in Chinese Rhubarb Products

    PubMed Central

    Hu, Huijuan; Li, Yanpeng; Liu, Chunsheng; Wei, Shengli

    2016-01-01

    To provide a basis for controlling the quality of rhubarb under artificial cultivation, the present work was designed to evaluate the contents of 14 active pharmaceutical ingredients (API) of rhubarb in major rhubarb production areas in China and analyze the correlations between the contents of API and such factors as species, geographic distribution and soil. The levels of fourteen API in rhubarb were measured using HPLC. The geographic distributions were collected using GPS and the nutrients in the soil were measured using the methods in the literature. The results showed that the levels of major API vary significantly among plants of different locations according to variance analysis. The species factor has few obvious effect on the overall properties of the rhubarb by the cluster analysis because of the two source species occurring in all divided three groups. However, Rheum tanguticum Maxim.ex Balf. is less effective at synthesizing and accumulating 9 API out of 14 than Rheum palmatum L. The correlation analysis and regression analysis also indicated that a lower latitude should be considered in the accumulation of API and a lower longitude should be considered to produce more compound anthraquinones. Lower levels of total P, rapidly available P and available molybdenum (Mo) and higher available K and available Zn in the soil were significantly correlated to accumulation of API in rhubarb. These results provide a basis for the clinical application and controlling the levels of the major API of rhubarb during artificial cultivation. PMID:27138597

  4. Plastic litter accumulation on high-water strandline of urban beaches in Mumbai, India.

    PubMed

    Jayasiri, H B; Purushothaman, C S; Vennila, A

    2013-09-01

    Today, almost every beach on every coastline is threatened by human activities. The inadequate recycling and poor management of waste in developing countries has resulted in considerable quantities of plastic contaminating beaches. Though India has long coastline of 5,420 km along the mainland with 43 % of sandy beaches, data on litter accumulation, particularly the plastics, which are one of the most common and persistent pollutants in marine environment, are scanty. The abundance and distribution of plastic litter was quantitatively assessed in four sandy beaches in Mumbai, India, bimonthly from May 2011 to March 2012. Triplicates of 2 × 2 m (4 m(2)) quadrats were sampled in each beach with a total of 72 quadrats. Overall, average abundance of 11.6 items m(-2) (0.25-282.5 items m(-2)) and 3.24 g m(-2) (0.27-15.53 g m(-2)) plastic litter was recorded in Mumbai beaches. Plastic litter accumulation significantly varied temporally and spatially at p = 0.05. Significantly higher plastic litter accumulation was recorded in Juhu beach. Furthermore, the highest abundance by weight was recorded in November and May numerically. More than 80 % of plastic particles were within the size range of 5-100 mm both by number and weight. Moreover, coloured plastics were predominant with 67 % by number of items and 51 % by weight. Probably, the intense use of beaches for recreation, tourism, and religious activities has increased the potential for plastic contamination in urban beaches in Mumbai.

  5. [Effect of arbuscular mycorrhizae on growth, heavy metal uptake and accumulation of Zenia insignis Chun seedlings].

    PubMed

    Li, Xia; Peng, Xia-Wei; Wu, Song-Lin; Li, Zhi-Ru; Feng, Hong-Mei; Jiang, Ze-Ping

    2014-08-01

    To solve the trace metal pollution of a Pd/Zn mine in Hunan province, a greenhouse pot experiment was conducted to investigate the effect of two arbuscular mycorrhizal fungi, Glomus mosseae (Gm) and Glomus intraradices (Gi), on the growth, heavy metal uptake and accumulation of Zenia insignis Chun, the pioneer plant there. The results showed that symbiotic associations were successfully established between the two isolates and Z. insignis in heavy metal contaminated soil. AM fungi improved P absorption, biomass and changed heavy metal uptake and distribution of Z. insignis. AM fungi-inoculated plants had significantly lower Fe, Cu, Zn, Pd concentrations and higher Fe, Cu, Zn, Pd accumulation than non-inoculated plants. However, Gm and Gi showed different mycorrhizal effects on the distribution of heavy metal in hosts, depending on the species of heavy metal. Gi-inoculated Z. insignis showed significantly lower TF values of Fe, Zn, Pd than Gm and non-inoculated plants, while both strains had no effect on TF value of Cu, which indicated that Gi enhanced trace metal accumulation in root system, playing a filtering/sequestering role in the presence of trace metals. The overall results demonstrated that AM fungi had positive effect on Z. insignis in enhancing the ability to adapt the heavy metal contaminated soil and played potential role in the revegetation of heavy metal contaminated soil. But in practical application, the combination of AM, hosts and heavy metal should be considered. PMID:25338391

  6. Influence of the Environmental Factors on the Accumulation of the Bioactive Ingredients in Chinese Rhubarb Products.

    PubMed

    Ren, Guangxi; Li, Li; Hu, Huijuan; Li, Yanpeng; Liu, Chunsheng; Wei, Shengli

    2016-01-01

    To provide a basis for controlling the quality of rhubarb under artificial cultivation, the present work was designed to evaluate the contents of 14 active pharmaceutical ingredients (API) of rhubarb in major rhubarb production areas in China and analyze the correlations between the contents of API and such factors as species, geographic distribution and soil. The levels of fourteen API in rhubarb were measured using HPLC. The geographic distributions were collected using GPS and the nutrients in the soil were measured using the methods in the literature. The results showed that the levels of major API vary significantly among plants of different locations according to variance analysis. The species factor has few obvious effect on the overall properties of the rhubarb by the cluster analysis because of the two source species occurring in all divided three groups. However, Rheum tanguticum Maxim.ex Balf. is less effective at synthesizing and accumulating 9 API out of 14 than Rheum palmatum L. The correlation analysis and regression analysis also indicated that a lower latitude should be considered in the accumulation of API and a lower longitude should be considered to produce more compound anthraquinones. Lower levels of total P, rapidly available P and available molybdenum (Mo) and higher available K and available Zn in the soil were significantly correlated to accumulation of API in rhubarb. These results provide a basis for the clinical application and controlling the levels of the major API of rhubarb during artificial cultivation. PMID:27138597

  7. 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.

  8. Plastic litter accumulation on high-water strandline of urban beaches in Mumbai, India.

    PubMed

    Jayasiri, H B; Purushothaman, C S; Vennila, A

    2013-09-01

    Today, almost every beach on every coastline is threatened by human activities. The inadequate recycling and poor management of waste in developing countries has resulted in considerable quantities of plastic contaminating beaches. Though India has long coastline of 5,420 km along the mainland with 43 % of sandy beaches, data on litter accumulation, particularly the plastics, which are one of the most common and persistent pollutants in marine environment, are scanty. The abundance and distribution of plastic litter was quantitatively assessed in four sandy beaches in Mumbai, India, bimonthly from May 2011 to March 2012. Triplicates of 2 × 2 m (4 m(2)) quadrats were sampled in each beach with a total of 72 quadrats. Overall, average abundance of 11.6 items m(-2) (0.25-282.5 items m(-2)) and 3.24 g m(-2) (0.27-15.53 g m(-2)) plastic litter was recorded in Mumbai beaches. Plastic litter accumulation significantly varied temporally and spatially at p = 0.05. Significantly higher plastic litter accumulation was recorded in Juhu beach. Furthermore, the highest abundance by weight was recorded in November and May numerically. More than 80 % of plastic particles were within the size range of 5-100 mm both by number and weight. Moreover, coloured plastics were predominant with 67 % by number of items and 51 % by weight. Probably, the intense use of beaches for recreation, tourism, and religious activities has increased the potential for plastic contamination in urban beaches in Mumbai. PMID:23430068

  9. Health hazards and heavy metals accumulation by summer squash (Cucurbita pepo L.) cultivated in contaminated soils.

    PubMed

    Galal, Tarek M

    2016-07-01

    The present study was carried out to investigate the heavy metal concentration accumulated by summer squash cultivated in contaminated soil and their health hazards for public consumers at south Cairo Province, Egypt. Soil and plants were sampled from contaminated and reference farms, using 1 m(2) quadrats, for biomass estimation and nutrient analysis. The daily intake of metals (DIM) and health risk index (HRI) were estimated. Significant differences in soil variables (except As) between contaminated and reference sites were recognized. Summer squash showed remarkable reduction in fresh and dry biomass, fruit production, and photosynthetic pigments under pollution stress. The inorganic and organic nutrients in the aboveground and belowground parts showed significant reduction in contaminated site. In addition, higher concentrations of heavy metals were accumulated in the edible parts and roots more than shoots. The bioaccumulation factor of summer squash for investigated metals was greater than 1, while the translocation factor did not exceed unity in both contaminated and reference sites. The DIM for all investigated metals in the reference site and in the contaminated site (except Fe and Mn) did not exceed 1 in both adults and children. However, HRI of Ni and Mn in the reference site and Pb, Cd, Cu, Ni, Fe, Mn, and Zn in the contaminated one exceeded unity indicating great potential to pose health risk to the consumers. The author recommends that people living in the contaminated area should not eat large quantities of summer squash, so as to avoid excess accumulation of heavy metals in their bodies.

  10. Influence of the Environmental Factors on the Accumulation of the Bioactive Ingredients in Chinese Rhubarb Products.

    PubMed

    Ren, Guangxi; Li, Li; Hu, Huijuan; Li, Yanpeng; Liu, Chunsheng; Wei, Shengli

    2016-01-01

    To provide a basis for controlling the quality of rhubarb under artificial cultivation, the present work was designed to evaluate the contents of 14 active pharmaceutical ingredients (API) of rhubarb in major rhubarb production areas in China and analyze the correlations between the contents of API and such factors as species, geographic distribution and soil. The levels of fourteen API in rhubarb were measured using HPLC. The geographic distributions were collected using GPS and the nutrients in the soil were measured using the methods in the literature. The results showed that the levels of major API vary significantly among plants of different locations according to variance analysis. The species factor has few obvious effect on the overall properties of the rhubarb by the cluster analysis because of the two source species occurring in all divided three groups. However, Rheum tanguticum Maxim.ex Balf. is less effective at synthesizing and accumulating 9 API out of 14 than Rheum palmatum L. The correlation analysis and regression analysis also indicated that a lower latitude should be considered in the accumulation of API and a lower longitude should be considered to produce more compound anthraquinones. Lower levels of total P, rapidly available P and available molybdenum (Mo) and higher available K and available Zn in the soil were significantly correlated to accumulation of API in rhubarb. These results provide a basis for the clinical application and controlling the levels of the major API of rhubarb during artificial cultivation.

  11. [Metal accumulation and MTLP induction in the digestive glands of Perna viridis exposed to Cu].

    PubMed

    Li, Chun-Di; Yan, Wen; Long, Ai-Min; Ma, Fu-Jun; Chen, Shao-Yong

    2007-08-01

    Mussels have been proposed as appropriate biomonitors of marine pollution, especially for monitoring metallic pollution based on variations of metallothionein as biomarkers. Under 2 exposure levels (12.7 microg/L, 63.5 microg/L), Cu accumulation and metallothionein-like protein (MTLP) induction by mussel (Perna viridis) digestive glands were investigated and simulated into dynamic models in the present work, and the soluble and total Cu burden of digestive glands were also determined. Calculated mean Cu uptake rates by mussel target organ were 2.045 and 7.028 microg x (g x d)(-1) respectively, and the theoretical equilibrium kinetic BCFs of Cu were 2074 and 1619 correspondingly. And within the exposure duration, different changing trends of ratio of soluble Cu to total Cu in digestive glands were observed in the two groups. The MTLP level of control samples was (0.551 +/- 0.037) mg/g, and the counterparts are 0.407 - 0.699 mg/g, 0.826 - 0.942 mg/g respectively when mussels were exposed to 12.7 microg/L and 63.5 microg/L Cu solutions. Statistically significant MTLP induction (p < 0.001) was observed under higher exposure level. MTLP contents in digestive glands increased with the exposure Cu concentration and body accumulation of metal. There is a significantly negative exponential rise relationship (p < 0.000 1) between MTLP and Cu concentrations accumulated in the digestive glands of mussels.

  12. [Effect of arbuscular mycorrhizae on growth, heavy metal uptake and accumulation of Zenia insignis Chun seedlings].

    PubMed

    Li, Xia; Peng, Xia-Wei; Wu, Song-Lin; Li, Zhi-Ru; Feng, Hong-Mei; Jiang, Ze-Ping

    2014-08-01

    To solve the trace metal pollution of a Pd/Zn mine in Hunan province, a greenhouse pot experiment was conducted to investigate the effect of two arbuscular mycorrhizal fungi, Glomus mosseae (Gm) and Glomus intraradices (Gi), on the growth, heavy metal uptake and accumulation of Zenia insignis Chun, the pioneer plant there. The results showed that symbiotic associations were successfully established between the two isolates and Z. insignis in heavy metal contaminated soil. AM fungi improved P absorption, biomass and changed heavy metal uptake and distribution of Z. insignis. AM fungi-inoculated plants had significantly lower Fe, Cu, Zn, Pd concentrations and higher Fe, Cu, Zn, Pd accumulation than non-inoculated plants. However, Gm and Gi showed different mycorrhizal effects on the distribution of heavy metal in hosts, depending on the species of heavy metal. Gi-inoculated Z. insignis showed significantly lower TF values of Fe, Zn, Pd than Gm and non-inoculated plants, while both strains had no effect on TF value of Cu, which indicated that Gi enhanced trace metal accumulation in root system, playing a filtering/sequestering role in the presence of trace metals. The overall results demonstrated that AM fungi had positive effect on Z. insignis in enhancing the ability to adapt the heavy metal contaminated soil and played potential role in the revegetation of heavy metal contaminated soil. But in practical application, the combination of AM, hosts and heavy metal should be considered.

  13. Influence of Squid Liver Powder on Accumulation of Cadmium in Serum, Kidney and Liver of Mice

    PubMed Central

    Kim, Byoung-Mok; Lee, Soo-Young; Jeong, In-Hak

    2013-01-01

    In this study, the effect of squid liver powder intake on accumulation of cadmium in mice was investigated. Subjects were divided into 4 groups including the control group (CON), squid liver powder group with lipids not removed (SLP100), and squid liver powder groups with lipids removed (LFSLP50 and LFSLP100). Feed intake and food efficiency ratio of squid liver powder groups was significantly higher than the CON. As a result of investigating cadmium content in hair, serum, liver, and kidney during intake of squid liver powder, all groups showed increase in cadmium accumulation through consistent, long-term intake. Especially, cadmium content in liver and kidney of LFSLP100 was significantly higher than the content of SLP100 and CON. As a result of pathological observation on liver and kidney tissues according to squid liver powder diet, LFSLP100 showed most serious pathological symptoms. In case of kidney tissues, degeneration was significantly more severe in LFSLP100 compared to other groups. Such results suggest that cadmium concentration in human body can be increased by ingestion of whole squid including internal organs and that tissues can be damaged by increased cadmium concentration. More specific and systematic studies are deemed necessary. PMID:24471103

  14. Influence of squid liver powder on accumulation of cadmium in serum, kidney and liver of mice.

    PubMed

    Kim, Byoung-Mok; Lee, Soo-Young; Jeong, In-Hak

    2013-03-01

    In this study, the effect of squid liver powder intake on accumulation of cadmium in mice was investigated. Subjects were divided into 4 groups including the control group (CON), squid liver powder group with lipids not removed (SLP100), and squid liver powder groups with lipids removed (LFSLP50 and LFSLP100). Feed intake and food efficiency ratio of squid liver powder groups was significantly higher than the CON. As a result of investigating cadmium content in hair, serum, liver, and kidney during intake of squid liver powder, all groups showed increase in cadmium accumulation through consistent, long-term intake. Especially, cadmium content in liver and kidney of LFSLP100 was significantly higher than the content of SLP100 and CON. As a result of pathological observation on liver and kidney tissues according to squid liver powder diet, LFSLP100 showed most serious pathological symptoms. In case of kidney tissues, degeneration was significantly more severe in LFSLP100 compared to other groups. Such results suggest that cadmium concentration in human body can be increased by ingestion of whole squid including internal organs and that tissues can be damaged by increased cadmium concentration. More specific and systematic studies are deemed necessary.

  15. Variability of cadmium, lead, and zinc tolerance and accumulation among and between germplasms of the fiber crop Boehmeria nivea with different root-types.

    PubMed

    Yang, B; Zhou, M; Zhou, L L; Xue, N D; Zhang, S L; Lan, C Y

    2015-09-01

    Crop germplasms substantially vary in their tolerance for and accumulation of heavy metals, and assessment of this variability plays a significant role in selecting species to use in phytoremediation projects. Here, we examined germplasm-variations in cadmium (Cd), lead (Pb), and zinc (Zn) tolerance and accumulation in ramie (Boehmeria nivea), a fiber crop native to China, which has received little attention. In an 8-week greenhouse test, fourteen germplasms of ramie, among and within deep, middle, and shallow rooted-types, were compared for growth and metal accumulation traits. Results showed that both tolerance and accumulation traits varied across germplasms and rooted-types. The deep rooted-type germplasms produced more biomass and had higher tolerance to metals than the two others. In addition, considerable variations in metal accumulation were observed among plant organs (root, stem, and leaf), rooted-types, germplasms, and metal supply. However, the observed variations in metal tolerance and accumulation among both germplasms and rooted-types were not significant in most cases. In addition to supporting the idea of a certain degree of constitutional metal tolerance for ramie, our results also contribute to deep-rooted germplasms of ramie as a good candidate, rather than middle-/shallow- ones as a least-bad option, for the remediation of multi metal-contaminated soils. PMID:25948381

  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. Asian Americans and Higher Education.

    ERIC Educational Resources Information Center

    Endo, Russell

    Unfortunately the story of Asian Americans and higher education is not one of unqualified success. This paper attempts to overview the historical significance and present the problems of Asian Americans in higher education. The first problem is the lack of oral and writing skills among Asian Americans. Part of this problem is cultural, referring…

  18. Disruptive Technologies in Higher Education

    ERIC Educational Resources Information Center

    Flavin, Michael

    2012-01-01

    This paper analyses the role of "disruptive" innovative technologies in higher education. In this country and elsewhere, Higher Education Institutions (HEIs) have invested significant sums in learning technologies, with Virtual Learning Environments (VLEs) being more or less universal, but these technologies have not been universally adopted and…

  19. Women in Higher Education, 1994.

    ERIC Educational Resources Information Center

    Wenninger, Mary Dee, Ed.

    1994-01-01

    This document consists of the 12 monthly issues of a newsletter on women students, teachers, and administrators in higher education, issued in 1994. Each issue includes feature articles, news on higher education, profiles of significant people in the field, and job announcements. The issues' main article topics are: (1) campuses's changing…

  20. 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.

  1. 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

  2. Salicylate Accumulation Inhibits Growth at Chilling Temperature in Arabidopsis1

    PubMed Central

    Scott, Ian M.; Clarke, Shannon M.; Wood, Jacqueline E.; Mur, Luis A.J.

    2004-01-01

    The growth of Arabidopsis plants in chilling conditions could be related to their levels of salicylic acid (SA). Plants with the SA hydroxylase NahG transgene grew at similar rates to Col-0 wild types at 23°C, and growth of both genotypes was slowed by transfer to 5°C. However, at 5°C, NahG plants displayed relative growth rates about one-third greater than Col-0, so that by 2 months NahG plants were typically 2.7-fold larger. This resulted primarily from greater cell expansion in NahG rosette leaves. Specific leaf areas and leaf area ratios remained similar in both genotypes. Net assimilation rates were similar in both genotypes at 23°C, but higher in NahG at 5°C. Chlorophyll fluorescence measurements revealed no PSII photodamage in chilled leaves of either genotype. Col-0 shoots at 5°C accumulated SA, particularly in glucosylated form. SA in NahG shoots showed similar tendencies at 5°C, but at greatly depleted levels. Catechol was not detected as a metabolite of the NahG transgene product. We also examined growth and SA levels in SA signaling and metabolism mutants at 5°C. The partially SA-insensitive npr1 mutant displayed growth intermediate between NahG and Col-0, while the SA-deficient eds5 mutant behaved like NahG. In contrast, the cpr1 mutant at 5°C accumulated very high levels of SA and its growth was much more inhibited than wild type. At both temperatures, cpr1 was the only SA-responsive genotype in which oxidative damage (measured as thiobarbituric acid-reactive substances) was significantly different from wild type. PMID:15173571

  3. 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.

  4. Expression of cadR Enhances its Specific Activity for Cd Detoxification and Accumulation in Arabidopsis.

    PubMed

    Li, Jingrui; Wei, Xuezhi; Yu, Pengli; Deng, Xin; Xu, Wenxiu; Ma, Mi; Zhang, Haiyan

    2016-08-01

    Cadmium (Cd) is a transition metal that is highly toxic in biological systems. Anthropogenic emissions of Cd have increased biogeochemical cycling and the amount of Cd in the biosphere. Here we studied the utility of a bacterial Cd-binding protein, CadR, for the remediation of Cd contamination. CadR was successfully targeted to chloroplasts using a constitutive Cauliflower mosaic virus (CaMV) 35S promoter or a shoot-specific Chl a/b-binding protein 2 gene (CAB2) promoter and an RbcS (small subunit of the Rubisco complex) transit peptide. Under short-term (2 d) exposure to Cd, the cadR transgenic plants showed up to a 2.9-fold Cd accumulation in roots compared with untransformed plants. Under medium term (7 d) exposure to Cd, the concentrations of Cd in leaves began to increase but there were no differences between the wild type and the cadR transgenic plants. Under long-term (16 d) exposure to Cd, the cadR transgenic plants accumulated greater amounts of Cd in leaves than the untransformed plants. Total Cd accumulation (µg per plant) in shoots and roots of the plants expressing cadR were significantly higher (up to 3.5-fold in shoots and 5.2-fold in roots) than those of the untransformed plants. We also found that targeting CadR to chloroplasts facilitated chloroplastic metal homeostasis and Chl b accumulation. Our results demonstrate that manipulating chelating capacity in chloroplasts or in the cytoplasm may be effective in modifying both the accumulation of and resistance to Cd.

  5. Expression of cadR Enhances its Specific Activity for Cd Detoxification and Accumulation in Arabidopsis.

    PubMed

    Li, Jingrui; Wei, Xuezhi; Yu, Pengli; Deng, Xin; Xu, Wenxiu; Ma, Mi; Zhang, Haiyan

    2016-08-01

    Cadmium (Cd) is a transition metal that is highly toxic in biological systems. Anthropogenic emissions of Cd have increased biogeochemical cycling and the amount of Cd in the biosphere. Here we studied the utility of a bacterial Cd-binding protein, CadR, for the remediation of Cd contamination. CadR was successfully targeted to chloroplasts using a constitutive Cauliflower mosaic virus (CaMV) 35S promoter or a shoot-specific Chl a/b-binding protein 2 gene (CAB2) promoter and an RbcS (small subunit of the Rubisco complex) transit peptide. Under short-term (2 d) exposure to Cd, the cadR transgenic plants showed up to a 2.9-fold Cd accumulation in roots compared with untransformed plants. Under medium term (7 d) exposure to Cd, the concentrations of Cd in leaves began to increase but there were no differences between the wild type and the cadR transgenic plants. Under long-term (16 d) exposure to Cd, the cadR transgenic plants accumulated greater amounts of Cd in leaves than the untransformed plants. Total Cd accumulation (µg per plant) in shoots and roots of the plants expressing cadR were significantly higher (up to 3.5-fold in shoots and 5.2-fold in roots) than those of the untransformed plants. We also found that targeting CadR to chloroplasts facilitated chloroplastic metal homeostasis and Chl b accumulation. Our results demonstrate that manipulating chelating capacity in chloroplasts or in the cytoplasm may be effective in modifying both the accumulation of and resistance to Cd. PMID:27382127

  6. Accumulation of polychlorinated biphenyl congeners from Lake Champlain sediments by Mysis relicta

    SciTech Connect

    Lester, D.C.; McIntosh, A. . Vermont Water Resources and Lake Studies Center)

    1994-11-01

    Polychlorinated biphenyl (PCB) levels in lake trout (Salvelinus namaycush) from Lake Champlain often exceed the F.D.A. tolerance level of 2 [mu]g/g (wet weight). Of added concern are recent studies that suggest a relationship between the dioxin-like properties of non-ortho-substituted PCB congeners and impaired lake trout egg hatchability. Dietary accumulation of PCBs is thought to be an important exposure route for fish. The epibenthic freshwater shrimp Mysis relicta is an integral part of the benthic and pelagic food web in lake Champlain and may act as a link between PCBs in sediments and lake trout. Previous investigations have shown that diurnal migrations of mysids enhance the movement and distribution of toxic contaminants, effectively coupling the benthic and pelagic zones. The objective of this research was to examine the role contaminated sediments play in the transfer of PCBs to mysids. Bioaccumulation was assessed by exposing mysids to such sediments in two ways: (a) with organisms screened from sediments; and (b) with organisms in direct contact with sediments. Accumulation of PCBs over the course of the 24-day exposure period was examined on the following days: 0, 3, 6, 12, 21, and 24. Eighty-nine individual PCB congeners were measured in tissue and sediment. Mysids in direct contact with sediments accumulated significantly higher levels of PCBs than did organisms screened from sediments. Mysids accumulated substantial levels of PCBs, suggesting they may play an important part in the transfer of PCBs from sediments into the Lake Champlain food web. It is clear from this research that sediments can play a critical role in the accumulation of PCBs by mysids.

  7. 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

  8. Regulation of Monoterpene Accumulation in Leaves of Peppermint1

    PubMed Central

    Gershenzon, Jonathan; McConkey, Marie E.; Croteau, Rodney B.

    2000-01-01

    Plants synthesize numerous classes of natural products that accumulate during development and are thought to function as constitutive defenses against herbivores and pathogens. However, little information is available about how the levels of such defenses are regulated. We measured the accumulation of monoterpenes, a model group of constitutive defenses, in peppermint (Mentha × piperita L.) leaves and investigated several physiological processes that could regulate their accumulation: the rate of biosynthesis, the rate of metabolic loss, and the rate of volatilization. Monoterpene accumulation was found to be restricted to leaves of 12 to 20 d of age, the period of maximal leaf expansion. The rate of monoterpene biosynthesis determined by 14CO2 incorporation was closely correlated with monoterpene accumulation, as determined by gas chromatographic analysis, and appeared to be the principal factor controlling the monoterpene level of peppermint leaves. No significant catabolic losses of monoterpenes were detected throughout leaf development, and monoterpene volatilization was found to occur at a very low rate, which, on a monthly basis, represented less than 1% of the total pool of stored monoterpenes. The composition of volatilized monoterpenes differed significantly from that of the total plant monoterpene pool, suggesting that these volatilized products may arise from a separate secretory system. With the demonstration that the rate of biosynthesis is the chief process that determines monoterpene accumulation in peppermint, efforts to improve production in this species can now focus on the genes, enzymes, and cell differentiation processes that regulate monoterpene biosynthesis. PMID:10631264

  9. Arsenic accumulation and tolerance in rootless macrophyte Najas indica are mediated through antioxidants, amino acids and phytochelatins.

    PubMed

    Tripathi, Rudra Deo; Singh, Ragini; Tripathi, Preeti; Dwivedi, Sanjay; Chauhan, Reshu; Adhikari, Bijan; Trivedi, Prabodh Kumar

    2014-12-01

    Arsenic (As) accumulation and tolerance response of a submerged rootless macrophyte Najas indica were evaluated during arsenate (As(V); 10-250 μM) and arsenite (As(III); 1-50 μM) exposure. Higher As accumulation at As(III) exposure and more tolerance upon As(V) exposure resulted in more toxicity during As(III) stress than As(V), which was evident through measurement of growth parameters and oxidative stress related parameters viz., lipid peroxidation (MDA content), electrical conductivity (EC) and hydrogen peroxide (H2O2) levels. Antioxidant enzymes and various amino acids were more prominent during moderate exposure of As(V), suggesting their possible role in As tolerance and detoxification. Various non-enzymatic antioxidant metabolites viz., ascorbic acid (ASC), glutathione (GSH), non-protein thiols (NPTs) and phytochelatins (PCs) biosynthesis involving phytochelatin synthase (PCS) activity increased more significantly during As(III) stress. However, PCs content seems inadequate in response to As accumulation leading to lower PC-SH:As molar ratio and higher As phytotoxicity during As(III) stress. N. indica may prove useful plant species for phytoremediation purpose in moderately As contaminated water bodies due to high As accumulation and tolerance potential. PMID:25456221

  10. Arsenic accumulation and tolerance in rootless macrophyte Najas indica are mediated through antioxidants, amino acids and phytochelatins.

    PubMed

    Tripathi, Rudra Deo; Singh, Ragini; Tripathi, Preeti; Dwivedi, Sanjay; Chauhan, Reshu; Adhikari, Bijan; Trivedi, Prabodh Kumar

    2014-12-01

    Arsenic (As) accumulation and tolerance response of a submerged rootless macrophyte Najas indica were evaluated during arsenate (As(V); 10-250 μM) and arsenite (As(III); 1-50 μM) exposure. Higher As accumulation at As(III) exposure and more tolerance upon As(V) exposure resulted in more toxicity during As(III) stress than As(V), which was evident through measurement of growth parameters and oxidative stress related parameters viz., lipid peroxidation (MDA content), electrical conductivity (EC) and hydrogen peroxide (H2O2) levels. Antioxidant enzymes and various amino acids were more prominent during moderate exposure of As(V), suggesting their possible role in As tolerance and detoxification. Various non-enzymatic antioxidant metabolites viz., ascorbic acid (ASC), glutathione (GSH), non-protein thiols (NPTs) and phytochelatins (PCs) biosynthesis involving phytochelatin synthase (PCS) activity increased more significantly during As(III) stress. However, PCs content seems inadequate in response to As accumulation leading to lower PC-SH:As molar ratio and higher As phytotoxicity during As(III) stress. N. indica may prove useful plant species for phytoremediation purpose in moderately As contaminated water bodies due to high As accumulation and tolerance potential.

  11. Triacylglycerol Metabolism, Function, and Accumulation in Plant Vegetative Tissues.

    PubMed

    Xu, Changcheng; Shanklin, John

    2016-04-29

    Oils in the form of triacylglycerols are the most abundant energy-dense storage compounds in eukaryotes, and their metabolism plays a key role in cellular energy balance, lipid homeostasis, growth, and maintenance. Plants accumulate oils primarily in seeds and fruits. Plant oils are used for food and feed and, increasingly, as feedstocks for biodiesel and industrial chemicals. Although plant vegetative tissues do not accumulate significant levels of triacylglycerols, they possess a high capacity for their synthesis, storage, and metabolism. The development of plants that accumulate oil in vegetative tissues presents an opportunity for expanded production of triacylglycerols as a renewable and sustainable bioenergy source. Here, we review recent progress in the understanding of triacylglycerol synthesis, turnover, storage, and function in leaves and discuss emerging genetic engineering strategies targeted at enhancing triacylglycerol accumulation in biomass crops. Such plants could potentially be modified to produce oleochemical feedstocks or nutraceuticals. PMID:26845499

  12. Factors influencing 7Be accumulation on rock varnish

    NASA Astrophysics Data System (ADS)

    Moore, Willard S.; Liu, Tanzhuo; Broecker, Wallace S.; Finkel, Robert C.; Wright, Allen

    Rocks coated with desert varnish were translocated from Scottsdale, Arizona, and Panamint Valley, California, to a fenced-in plot near Biosphere 2 where they were allowed to accumulate a new crop of the 53 day half life, cosmic ray-produced 7Be. Those exposed to precipitation accumulated several times more of this isotope than those shielded from precipitation. No significant difference in 7Be accumulation was observed between a set which was UV irradiated (in an attempt to kill resident bacteria) and a set which received no UV irradiation. This experiment suggests that 62 ± 10 percent of the beryllium accumulated on the varnish was supplied by precipitation and 38 ± 10 percent by some combination of dew, dust, and aerosols. If bacteria are, as has been proposed, responsible for varnish growth, then either our UV irradiation was inadequate to squelch their activity or the 7Be we measured had not yet been built into the varnish.

  13. 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 Pbsignificant difference was observed between the enrichment coefficient average of Cd and Cu (P<0.05). The enrichment coefficients were higher 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

  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. Jasmonic acid enhancement of anthocyanin accumulation is dependent on phytochrome A signaling pathway under far-red light in Arabidopsis.

    PubMed

    Li, Ting; Jia, Kun-Peng; Lian, Hong-Li; Yang, Xu; Li, Ling; Yang, Hong-Quan

    2014-11-01

    Anthocyanins are critical for plants. It is shown that the expression of genes encoding the key enzymes such as dihydroflavonol 4-reductase (DFR), UDP-Glc: flavonoid 3-O-glucosyltransferase (UF3GT), and leucoanthocyanidin dioxygenase (LDOX) in anthocyanin biosynthesis pathway is regulated by MYB75, a R2R3 MYB transcription factor. The production of anthocyanin is known to be promoted by jasmonic acid (JA) in light but not in darkness. The photoreceptors cryptochrome 1 (CRY1), phytochrome B (phyB), and phytochrome A (phyA) are also shown to mediate light promotion of anthocyanin accumulation, respectively, whereas their downstream factor COP1, a master negative regulator of photomorphogensis, represses anthocyanin accumulation. However, whether JA coordinates with photoreceptors in the regulation of anthocyanin accumulation is unknown. Here, we show that under far-red light, JA promotes anthocyanin accumulation in a phyA signaling pathway-dependent manner. The phyA mutant is hyposensitive to jasmonic acid analog methyl jasmonic acid (MeJA) under far-red light. The dominant mutant of MYB75, pap1-D, accumulates significantly higher levels of anthocyanin than wild type under far-red light, whereas knockdown of MYBs (MYB75, MYB90, MYB113, and MYB114) through RNAi significantly reduces MeJA promotion of anthocyanin accumulation. The phyA pap1-D double mutant shows reduced responsiveness to MeJA, similar to phyA mutant under far-red light. In darkness, a mutant allele of cop1, cop1-4, shows enhanced responsiveness to MeJA, but pap1-D mutant is barely responsive to MeJA. Upon MeJA application, the cop1-4 pap1-D double mutant accumulates considerably higher levels of anthocyanin than cop1-4 in darkness. Protein studies indicate that MYB75 protein is stabilized by white light and far-red light. Further gene expression studies suggest that MeJA promotes the expression of DFR, UF3GT, and LDOX genes in a phyA- and MYB75-dependent manner under far-red light. Our findings suggest

  17. Co-Variations of Ice Sheet Elevation and Slope with Accumulation, Radar Backscatter, and Temperature in West Antarctica

    NASA Astrophysics Data System (ADS)

    Haran, T.; Scambos, T.

    2004-12-01

    Maps of surface slope and elevation of the West Antarctic Ice Sheet (WAIS) may be refined by applying calibrated image pixel brightnesses to existing DEMs. Using these image-enhanced elevation models, and existing models of regional katabatic air flow, we investigate the relationship of accumulation, radar backscatter, and temperature to surface slope in the catchment area of the Ross Embayment ice streams. MODIS (Moderate Resolution Imaging Spectroradiometer) images were combined with the RAMP (Radarsat Antarctic Mapping Project) DEM and airborne laser altimeter profiles (from the ALICE/CASERTZ/SOAR aerogeophysics programs) to create a new 250-meter resolution slope and elevation DEM of the study region. The DEM fully resolves the surface undulation field of 2 - 10 km spatial scale, and permits an investigation of air-surface interaction effects in greater detail. Coupling this slope map with the regional mean wind pattern (Bromwich, pers. comm.), we compare local slope variations in the wind direction with accumulation variations derived from a 180-km ground-penetrating radar profile (Spikes, Hamilton, and Arcone, pers. comm.) and point accumulation measurements (Giovinetto, and Vaughan, pers. comm.). We also compare wind-direction slope and accumulation with radar backscatter intensity derived from the RAMP AMM-1 data set. Correlation between RAMP backscatter and accumulation along the traverse is very high (r = 0.8). Regions of higher accumulation are associated with lower backscatter. Accumulation varied as much as 3-fold over just 15 km in regions of significant local relief. Both backscatter and accumulation show high correlation (r= 0.7) with surface slope in the mean wind direction: higher accumulation occurs on windward slopes. This relationship suggests that slope, backscatter, and mean wind direction may be used to infer accumulation in high spatial detail throughout the continent. Mean surface temperature under clear-sky conditions also shows a

  18. A comparison of recent, short-, and long-term carbon accumulation rates for a vegetation gradient in central Alaska

    NASA Astrophysics Data System (ADS)

    Manies, K.; Harden, J. W.; Turetsky, M.; Fuller, C.

    2013-12-01

    Information regarding historical rates of carbon (C) accumulation will aid scientists in understanding how climate change may affect biogeochemical cycles in the future. We examined rates of C accumulation for the following three time periods: the last two thousand years (long-term rates), the last 30 years (short-term rates), and the last several years (recent rates). We compared C accumulation rates among these time periods for five different ecosystems found along a ~300-m transect within the Bonanza Creek Long-term Ecological Research (LTER) site. These sites were dominated by black spruce, low shrubs, tussock grass, Carex sp., or brown moss. The black spruce and shrub site are the only ecosystems currently underlain by permafrost. Three soil cores were taken at each site and analyzed for C content. In order to gain a robust understanding of C accumulation rates at each site, 14C measurements and 210Pb chronologies were also obtained, and flux measurements were taken at each site. 14C dates were acquired for the basal horizon of one profile for each ecosystem type, providing estimations of C accumulation rates since organic matter began to form. 210Pb chronologies for each soil profile allowed us to estimate C accumulation rates for the last several decades. Finally, CO2 flux measurements were taken at each site from May - September for five years (2007 - 2011), capturing recent C losses and gains. Although short-term C accumulation rates were lowest in the black spruce ecosystem, rates among ecosystems were not significantly different, due to large variability among soil profiles within each site (coefficient of variations of up to 50%). The long-term C accumulation rate at the black spruce site corresponds well to values measured in an adjacent black spruce forest using eddy covariance. The brown moss site had the highest long-term rates of C accumulation among the five ecosystems. Short-term C accumulation rates were always higher than long-term rates (40

  19. Subsidy policies with capital accumulation: maintaining employment levels.

    PubMed

    Dutta, B; Gang, I N; Gangopadhyay, S

    1989-12-01

    The authors study a dual economy model of growth and unemployment in the presence of Harris-Todaro type labor migration. The model is a discrete time model of economic growth with a given population but endogenous migration of labor. The economy tries to reach development in the quickest possible time while not allowing unemployment to rise above a socially acceptable level. The authors also characterize situations under which maximizing the accumulation of capital in each period is optimal and study how particular taxes and subsidies affect unemployment and capital accumulation. Finally, they show that a higher initial capital stock does not necessarily mean a quicker attainment of self- sustained full employment.

  20. Neurodegeneration with brain iron accumulation (NBIA)

    MedlinePlus

    ... gov/ency/article/001225.htm Neurodegeneration with brain iron accumulation (NBIA) To use the sharing features on this page, please enable JavaScript. Neurodegeneration with brain iron accumulation (formerly known as Hallervorden-Spatz disease) is ...

  1. The significance of research

    NASA Astrophysics Data System (ADS)

    2014-02-01

    When promoting the value of their research or procuring funding, researchers often need to explain the significance of their work to the community -- something that can be just as tricky as the research itself.

  2. T1 Relaxation Rate (R1) Indicates Nonlinear Mn Accumulation in Brain Tissue of Welders With Low-Level Exposure

    PubMed Central

    Lee, Eun-Young; Flynn, Michael R.; Du, Guangwei; Lewis, Mechelle M.; Fry, Rebecca; Herring, Amy H.; Van Buren, Eric; Van Buren, Scott; Smeester, Lisa; Kong, Lan; Yang, Qing; Mailman, Richard B.; Huang, Xuemei

    2015-01-01

    Although the essential element manganese (Mn) is neurotoxic at high doses, the effects of lower exposure are unclear. MRI T1-weighted (TIW) imaging has been used to estimate brain Mn exposure via the pallidal index (PI), defined as the T1W intensity ratio in the globus pallidus (GP) versus frontal white matter (FWM). PI may not, however, be sensitive to Mn in GP because Mn also may accumulate in FWM. This study explored: (1) whether T1 relaxation rate (R1) could quantify brain Mn accumulation more sensitively; and (2) the dose-response relationship between estimated Mn exposure and T1 relaxation rate (R1). Thirty-five active welders and 30 controls were studied. Occupational questionnaires were used to estimate hours welding in the past 90 days (HrsW) and lifetime measures of Mn exposure. T1W imaging and T1-measurement were utilized to generate PI and R1 values in brain regions of interest (ROIs). PI did not show a significant association with any measure of Mn and/or welding-related exposure. Conversely, in several ROIs, R1 showed a nonlinear relationship to HrsW, with R1 signal increasing only after a critical exposure was reached. The GP had the greatest rate of Mn accumulation. Welders with higher exposure showed significantly higher R1 compared either with controls or with welders with lower exposure. Our data are additional evidence that Mn accumulation can be assessed more sensitively by R1 than by PI. Moreover, the nonlinear relationship between welding exposure and Mn brain accumulation should be considered in future studies and policies. PMID:25953701

  3. Reflectance of litter accumulation levels at five wavelengths within the 0.5- to 2.5 micron waveband

    NASA Technical Reports Server (NTRS)

    Gerbermann, A. H.; Everitt, J. H.; Gausman, H. W. (Principal Investigator)

    1982-01-01

    Reflectance was measured for 1-m2 range grass plots with two canopy treatments (standing and clipped) and four levels of litter accumulation and for grain sorghum with two canopy treatments. Reflectance was significantly higher at the 0.65- to 1.65-, and 2.20-micrometer. Wavelengths for both grass and grain sorghum canopies when the canopies were clipped and the resulting litter was removed. The natural accumulation of litter under the grass canopy did not significantly affect reflectance. The 1.65- and 2.20-micrometer wavelength reflectances of the live grass and the intact litter were 21.8% and 16.2%, respectively, and those of grain sorghum were 21.8% and 16.5%, respectively.

  4. 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

  5. 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.

  6. Vegetation pattern and heavy metal accumulation at a mine tailing at Gyöngyösoroszi, hungary.

    PubMed

    Tamás, János; Kovács, Alza

    2005-01-01

    Vegetation at an abandoned heavy metal bearing mine tailing may have multifunctional roles such as modification of water balance, erosion control and landscape rehabilitation. Research on the vegetation of mine tailings can provide useful information on tolerance, accumulation and translocation properties of species potentially applicable at moderately contaminated sites. Analyses of the relationship between heavy metal content (Pb, Zn and Cu) and vegetation in a mine tailing were carried out. These analyses included: (1) spatial analysis of relationship among heavy metal distribution, pH and vegetation patterns, and (2) analysis of heavy metal accumulation and translocation in some plant species. Presence of vegetation was found to be significantly dependent on pH value, which confirms that phytotoxicity is a function of element concentration in solution, which is primarily controlled by pH value in mine tailings. Among the most abundant plant species, dewberry (Rubus caesius), vipersbugloss (Echium vulgare), scarlet pimpernel (Anagallis arvensis) and narrowleaf plantain (Plantago lanceolata) accumulate significant amounts of Pb, Cu and Zn, while in the case of annual bluegrass (Poa annua) only Pb can be measured in elevated contents. Considering the translocation features, scarlet pimpernel, narrowleaf plantain, and dewberry accumulate heavy metals primarily in their roots, while heavy metal concentration in vipersbugloss and annual bluegrass is higher in the shoots.

  7. Comparison of accumulation of micropollutants between igenous and transplanted zebra mussels (Dreissena polymorpha).

    PubMed

    Bervoets, Lieven; Voets, Judith; Chu, Shaogang; Covaci, Adrian; Schepens, Paul; Blust, Ronny

    2004-08-01

    Zebra mussels (Dreissena polymorpha) were exposed at 12 canals and lakes situated in Flanders (Belgium), in cages for six weeks during the summer of 2002. Accumulation of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), hexachlorobenzene, and trace metals were measured in the transplanted mussels and levels compared to levels in indigenous mussels. Additionally, zebra mussels were exposed at a small lake in the vicinity of Antwerp (Belgium), and accumulation of contaminants was followed for an extended period from December 2001 to April 2002. Analysis of the pollutants in the indigenous mussels showed that the selected sites displayed a wide range of pollution from near to background to very high levels of metals and/or organic contaminants when compared to the literature. For organic contaminants and for most metals, comparison of levels between caged and resident mussels revealed no significant differences. Only for cadmium and nickel, significant differences were observed, with levels being either higher (cadmium) or lower (nickel) in caged mussels. For organic contaminants, significant correlations between levels in caged and resident mussels were found with r2 values up to 0.98. For some metals, no or poor correlations were found. At most sites, concentrations of those metals were of the same order of magnitude and comparable to levels in mussels from unpolluted sites. This might explain the absence of significant correlations. When mussels were exposed for an extended period, the concentration of some pollutants increased, whereas others decreased with time. Only in the case of certain metals did levels differ significantly because of the slow depuration of metals already present in the transplanted mussels. This is an additional indication that measured concentrations in transplanted mussels indeed reflected the local situation. With this study, we were able to prove the applicability of transplanted mussels as a biomonitoring tool

  8. Comparative functional characterization of eugenol synthase from four different Ocimum species: Implications on eugenol accumulation.

    PubMed

    Anand, Atul; Jayaramaiah, Ramesha H; Beedkar, Supriya D; Singh, Priyanka A; Joshi, Rakesh S; Mulani, Fayaj A; Dholakia, Bhushan B; Punekar, Sachin A; Gade, Wasudeo N; Thulasiram, Hirekodathakallu V; Giri, Ashok P

    2016-11-01

    Isoprenoids and phenylpropanoids are the major secondary metabolite constituents in Ocimum genus. Though enzymes from phenylpropanoid pathway have been characterized from few plants, limited information exists on how they modulate levels of secondary metabolites. Here, we performed phenylpropanoid profiling in different tissues from five Ocimum species, which revealed significant variations in secondary metabolites including eugenol, eugenol methyl ether, estragole and methyl cinnamate levels. Expression analysis of eugenol synthase (EGS) gene showed higher transcript levels especially in young leaves and inflorescence; and were positively correlated with eugenol contents. Additionally, transcript levels of coniferyl alcohol acyl transferase, a key enzyme diverting pool of substrate to phenylpropanoids, were in accordance with their abundance in respective species. In particular, eugenol methyl transferase expression positively correlated with higher levels of eugenol methyl ether in Ocimum tenuiflorum. Further, EGSs were functionally characterized from four Ocimum species varying in their eugenol contents. Kinetic and expression analyses indicated, higher enzyme turnover and transcripts levels, in species accumulating more eugenol. Moreover, biochemical and bioinformatics studies demonstrated that coniferyl acetate was the preferred substrate over coumaryl acetate when used, individually or together, in the enzyme assay. Overall, this study revealed the preliminary evidence for varied accumulation of eugenol and its abundance over chavicol in these Ocimum species. Current findings could potentially provide novel insights for metabolic modulations in medicinal and aromatic plants. PMID:27519164

  9. Effect of a metal mixture on cadmium accumulation in transplanted macrophytes

    SciTech Connect

    Stewart, A.R.

    1995-12-31

    The effect of a metal mixture (Cu, Zn, Pb and Ni) on Cd accumulation in the freshwater macrophyte Eriocaulon septangulare, was examined in a mesocosm experiment at the Experimental Lakes Area, northwestern, Ontario. Cd was added alone to treatment 1 and together with the metal mixture (at three increasing levels) to treatments 2, 3, and 4. Each treatment was represented by two mesocosms. Macrophytes were collected from the littoral region of lake 104, transported to nearby Roddy lake, and planted in plastic gardening trays containing exposed limnocorral sediments. The trays were lowered to the bottom of the limnocorrals and after 40 and 80 days the macrophytes were analyzed for metal content. The transplanted macrophytes accumulated Cd in both their shoots and roots. On day 40, Cd levels in the shoots of macrophytes exposed to the highest level of metal mixture were lower than in shoots from macrophytes exposed to cadmium alone, Between day 40 to day 80 Cd was lost from the shoots of macrophytes in all treatments. Cd levels in roots were higher in macrophytes exposed to the metal mixture on day 40 and significantly higher on day 80 compared to exposure to Cd alone. Elevated Cd levels in the roots of macrophytes exposed to the metal mixture reflected higher Cd levels in the water. The macrophyte Eriocaulon shows promise in environmental monitoring where test species are transplanted.

  10. 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.

  11. Comparative functional characterization of eugenol synthase from four different Ocimum species: Implications on eugenol accumulation.

    PubMed

    Anand, Atul; Jayaramaiah, Ramesha H; Beedkar, Supriya D; Singh, Priyanka A; Joshi, Rakesh S; Mulani, Fayaj A; Dholakia, Bhushan B; Punekar, Sachin A; Gade, Wasudeo N; Thulasiram, Hirekodathakallu V; Giri, Ashok P

    2016-11-01

    Isoprenoids and phenylpropanoids are the major secondary metabolite constituents in Ocimum genus. Though enzymes from phenylpropanoid pathway have been characterized from few plants, limited information exists on how they modulate levels of secondary metabolites. Here, we performed phenylpropanoid profiling in different tissues from five Ocimum species, which revealed significant variations in secondary metabolites including eugenol, eugenol methyl ether, estragole and methyl cinnamate levels. Expression analysis of eugenol synthase (EGS) gene showed higher transcript levels especially in young leaves and inflorescence; and were positively correlated with eugenol contents. Additionally, transcript levels of coniferyl alcohol acyl transferase, a key enzyme diverting pool of substrate to phenylpropanoids, were in accordance with their abundance in respective species. In particular, eugenol methyl transferase expression positively correlated with higher levels of eugenol methyl ether in Ocimum tenuiflorum. Further, EGSs were functionally characterized from four Ocimum species varying in their eugenol contents. Kinetic and expression analyses indicated, higher enzyme turnover and transcripts levels, in species accumulating more eugenol. Moreover, biochemical and bioinformatics studies demonstrated that coniferyl acetate was the preferred substrate over coumaryl acetate when used, individually or together, in the enzyme assay. Overall, this study revealed the preliminary evidence for varied accumulation of eugenol and its abundance over chavicol in these Ocimum species. Current findings could potentially provide novel insights for metabolic modulations in medicinal and aromatic plants.

  12. Effect of vanadate on renal hypertrophy and sorbitol accumulation in streptozotocin induced diabetes in rats.

    PubMed

    Lohr, J W; Bennett, M I; Pochal, M A; McReynolds, J; Acara, M; Willsky, G R

    1991-05-01

    Vanadate has been previously shown to normalize blood glucose in streptozotocin-induced diabetic (STZ-DM) rats. The effect of a previously studied dose of vanadate (0.8 mg/ml) in drinking water on blood glucose, renal hypertrophy, and whole kidney polyol accumulation was studied in STZ-DM rats. Rats with diabetes of 5 weeks duration had higher blood glucose, greater urinary output, higher kidney weight, lower body weight, and higher kidney to body weight ratios than controls. Whole kidney sorbitol concentrations were significantly increased in diabetes but myo-inositol levels were unchanged vs control animals. After four weeks of oral vanadate treatment, blood glucose, urine volume, and kidney weights were similar to control values. Kidney to body weight ratios fell below that of the STZ-DM animals, but because body weights remained decreased, the kidney to body weight ratios were not normalized. Renal sorbitol levels returned to control values and renal myo-inositol levels remained unchanged in STZ-DM and normal animals treated with vanadate. These results provide evidence that vanadate therapy may result in regression of the hypertrophy and polyol accumulation characteristic of diabetic nephropathy in STZ-DM rats. This effect is most likely due to normalization of blood glucose by the insulin-mimetic activity of vanadate treatment.

  13. Enhanced lipid accumulation of photoautotrophic microalgae by high-dose CO2 mimics a heterotrophic characterization.

    PubMed

    Sun, Zhilan; Dou, Xiao; Wu, Jun; He, Bing; Wang, Yuancong; Chen, Yi-Feng

    2016-01-01

    Microalgae possess higher photosynthetic efficiency and accumulate more neutral lipids when supplied with high-dose CO2. However, the nature of lipid accumulation under conditions of elevated CO2 has not been fully elucidated so far. We now revealed that the enhanced lipid accumulation of Chlorella in high-dose CO2 was as efficient as under heterotrophic conditions and this may be attributed to the driving of enlarged carbon source. Both photoautotrophic and heterotrophic cultures were established by using Chlorella sorokiniana CS-1. A series of changes in the carbon fixation, lipid accumulation, energy conversion, and carbon-lipid conversion under high-dose CO2 (1-10%) treatment were characterized subsequently. The daily carbon fixation rate of C. sorokiniana LS-2 in 10% CO2 aeration was significantly increased compared with air CO2. Correspondingly, double oil content (28%) was observed in 10% CO2 aeration, close to 32.3% produced under heterotrophic conditions. In addition, with 10% CO2 aeration, the overall energy yield (Ψ) in Chlorella reached 12.4 from 7.3% (with air aeration) because of the enhanced daily carbon fixation rates. This treatment also improved the energetic lipid yield (Ylipid/Es) with 4.7-fold, tending to the heterotrophic parameters. More significantly, 2.2 times of carbon-lipid conversion efficiency (ηClipid/Ctotal, 42.4%) was observed in 10% CO2 aeration, towards to 53.7% in heterotrophic cultures, suggesting that more fixed carbon might flow into lipid synthesis under both 10% CO2 aeration and heterotrophic conditions. Taken together, all our evidence showed that 10% CO2 may push photoautotrophic Chlorella to display heterotrophic-like efficiency at least in lipid production. It might bring us an efficient model of lipid production based on microalgal cells with high-dose CO2, which is essential to sustain biodiesel production at large scales. PMID:26712624

  14. 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.

  15. Accumulation of advanced glycation end products, measured as skin autofluorescence, in renal disease.

    PubMed

    Hartog, Jasper W L; de Vries, Aiko P J; Lutgers, Helen L; Meerwaldt, Robbert; Huisman, Roel M; van Son, Willem J; de Jong, Paul E; Smit, Andries J

    2005-06-01

    Advanced glycation end products (AGEs) accumulate during renal failure and dialysis. Kidney transplantation is thought to reverse this accumulation by restoring renal function. Using a noninvasive and validated autofluorescence reader, we evaluated AGE levels in 285 transplant recipients (mean age, 52 years; range, 41 to 60 years), 32 dialysis patients (mean age, 56 years; range, 43 to 65 years), and 231 normal control subjects (mean age, 51 years; range, 40 to 65 years). Measurements in transplant recipients were performed for a mean of 73 months (range, 32 to 143 months) after transplantation. Dialysis patients were on dialysis therapy for a mean of 42 months (range, 17 to 107 months). Fluorescence was significantly increased in dialysis patients compared with normal control subjects (2.8 vs. 2.0 arbitrary units [a.u.], P < .0001). Although fluorescence levels were significantly decreased in transplant recipients compared with dialysis patients (2.5 vs. 2.8 a.u., P < .0001), fluorescence in transplant recipients was higher than in controls (2.5 vs. 2.0 a.u., P < .0001). In transplant recipients, fluorescence correlated positively with the duration of dialysis prior to transplantation (R = 0.21, P < .0001), and negatively with creatinine clearance (R = -0.34, P < .0001). No correlation was found between time after transplantation and fluorescence in transplant recipients (R = -0.10, P = .10). Fluorescence in dialysis patients was positively correlated with duration of dialysis (R = 0.36, P = .042). Our results, like those of others, suggest that kidney transplantation does not fully correct increased AGE levels found in dialysis patients. The increased AGE levels in kidney transplant recipients cannot be explained by the differences in renal function alone. The availability of a simple, noninvasive method (AGE-Reader) to measure AGE accumulation may be used to monitor AGE accumulation in a clinical setting as well as in a study setting.

  16. Effect of Nutrient Starvation under High Irradiance on Lipid and Starch Accumulation in Chlorella fusca (Chlorophyta).

    PubMed

    Jerez, Celia G; Malapascua, José R; Sergejevová, Magda; Figueroa, Félix L; Masojídek

    2016-02-01

    The effect of nitrogen and sulphur limitation under high irradiance (PAR) was studied in the green microalga Chlorella fusca (Chlorophyta) in order to follow lipid and/or starch accumulation. Growth, biomass composition and the changes in photosynthetic activity (in vivo chlorophyll a fluorescence) were followed in the trials. The full nutrient culture showed high biomass production and starch accumulation at Day 1, when photosynthetic activity was high. Gradual deprivation (no nutrients added) became evident when photosynthesis was significantly suppressed (Day 3 onwards), which entailed a decrease of maximum relative electron transport rate (rETRmax) and increase of non-photochemical quenching (NPQ), accompanied by the onset of lipid accumulation and decline in starch content. In N- and S-starved cultures, rETRmax significantly decreased by Day 3, which caused a substantial drop in biomass production, cell number, biovolume and induction of lipid and starch accumulation. High starch content (45-50 % of DW) was found at the initial stage in full nutrient culture and at the stationary phase in nutrient-starved cultures. By the end of the trial, all treatments showed high lipid content (~30 % of DW). The full nutrient culture had higher biomass yield than starved treatments although starch (~0.2 g L(-1) day(-1)) and lipid (~0.15 g L(-1) day(-1) productivities were fairly similar in all the cultures. Our results showed that we could enrich biomass of C. fusca (% DW) in lipids using a two-stage strategy (a nutrient replete stage followed by gradual nutrient limitation) while under either procedure, N- or S-starvation, both high lipid and starch contents could be achieved.

  17. Fructan accumulation and transcription of candidate genes during cold acclimation in three varieties of Poa pratensis.

    PubMed

    Rao, R Shyama Prasad; Andersen, Jeppe Reitan; Dionisio, Giuseppe; Boelt, Birte

    2011-03-01

    Poa pratensis, a type species for the grass family (Poaceae), is an important cool season grass that accumulates fructans as a polysaccharide reserve. We studied fructan contents and expression of candidate fructan metabolism genes during cold acclimation in three varieties of P. pratensis adapted to different environments: Northern Norway, Denmark, and the Netherlands. Fructan content increased significantly during cold acclimation and varieties showed significant differences in the level of fructan accumulation. cDNA sequences of putative fructosyltransferase (FT), fructan exohydrolase (FEH), and cold acclimation protein (CAP) genes were identified and cloned. In agreement with a function in fructan biosynthesis, transcription of a putative sucrose:fructan 6-fructosyltransferase (Pp6-SFT) gene was induced during cold acclimation and fructan accumulation in all three P. pratensis varieties. Transcription of putative PpFEH and PpCAP genes was also induced by cold acclimation; however, transcription of these two genes was several-fold higher in the variety from Norway compared to the other two varieties. The results presented here suggest that Pp6-SFT is involved in fructan biosynthesis in P. pratensis. FEHs have previously been suggested to be involved in fructan biosynthesis and freezing tolerance, and induced expression of PpFEH during fructan accumulation could also suggest a role in fructan biosynthesis. However, based on the different PpFEH transcription rates among varieties and similar expression of PpFEH and PpCAP, we suggest that PpFEH is more likely to be involved in mediating freezing tolerance, e.g., by regulating the cell osmotic potential through fructan degradation.

  18. The ability to accumulate deoxyuridine triphosphate and cellular response to thymidylate synthase (TS) inhibition

    PubMed Central

    Webley, S D; Welsh, S J; Jackman, A L; Aherne, G W

    2001-01-01

    Thymidylate synthase (TS) is an important enzyme catalysing the reductive methylation of dUMP to dTMP that is further metabolized to dTTP for DNA synthesis. Loss of viability following TS inhibition occurs as a consequence of depleted dTTP pools and at least in some cell lines, accumulation of dUTP and subsequent misincorporation of uracil into DNA. The expansion in dUTP pools is largely determined by the expression of the pyrophosphatase, dUTPase. Our previous work has shown that following TS inhibition the ability to accumulate dUTP was associated with an earlier growth inhibitory effect. 3 human lung tumour cell lines and HT29 human colon tumour cells transfected with dUTPase have been used to investigate the relationship between loss of viability following TS inhibition and dUTP accumulation. Cell cycle arrest typical of TS inhibition was an early event in all cell lines and occurred irrespective of the ability to accumulate dUTP or p53 function. However, a large expansion of dUTP pools was associated with mature DNA damage (4 h) and an earlier loss of viability following TS inhibition compared to cells in which dUTP pools were not expanded. In A549 cells damage to mature DNA may have been exacerbated by significantly higher activity of the excision repair enzyme, uracil-DNA glycosylase. Consistent with results using different inhibitors of TS, transfection of dUTPase into HT29 cells significantly reduced the cytotoxicity of a 24 h but not 48 h exposure to ZD9331. Although loss of viability can be mediated through dTTP deprivation alone, the uracil misincorporation pathway resulted in an earlier commitment to cell death. The relevance of this latter pathway in the clinical response to TS inhibitors deserves further investigation. © 2001 Cancer Research Campaign http://www.bjcancer.com PMID:11487279

  19. Accumulation of advanced glycation end products, measured as skin autofluorescence, in renal disease.

    PubMed

    Hartog, Jasper W L; de Vries, Aiko P J; Lutgers, Helen L; Meerwaldt, Robbert; Huisman, Roel M; van Son, Willem J; de Jong, Paul E; Smit, Andries J

    2005-06-01

    Advanced glycation end products (AGEs) accumulate during renal failure and dialysis. Kidney transplantation is thought to reverse this accumulation by restoring renal function. Using a noninvasive and validated autofluorescence reader, we evaluated AGE levels in 285 transplant recipients (mean age, 52 years; range, 41 to 60 years), 32 dialysis patients (mean age, 56 years; range, 43 to 65 years), and 231 normal control subjects (mean age, 51 years; range, 40 to 65 years). Measurements in transplant recipients were performed for a mean of 73 months (range, 32 to 143 months) after transplantation. Dialysis patients were on dialysis therapy for a mean of 42 months (range, 17 to 107 months). Fluorescence was significantly increased in dialysis patients compared with normal control subjects (2.8 vs. 2.0 arbitrary units [a.u.], P < .0001). Although fluorescence levels were significantly decreased in transplant recipients compared with dialysis patients (2.5 vs. 2.8 a.u., P < .0001), fluorescence in transplant recipients was higher than in controls (2.5 vs. 2.0 a.u., P < .0001). In transplant recipients, fluorescence correlated positively with the duration of dialysis prior to transplantation (R = 0.21, P < .0001), and negatively with creatinine clearance (R = -0.34, P < .0001). No correlation was found between time after transplantation and fluorescence in transplant recipients (R = -0.10, P = .10). Fluorescence in dialysis patients was positively correlated with duration of dialysis (R = 0.36, P = .042). Our results, like those of others, suggest that kidney transplantation does not fully correct increased AGE levels found in dialysis patients. The increased AGE levels in kidney transplant recipients cannot be explained by the differences in renal function alone. The availability of a simple, noninvasive method (AGE-Reader) to measure AGE accumulation may be used to monitor AGE accumulation in a clinical setting as well as in a study setting. PMID:16037252

  20. Changes in snowpack accumulation and ablation in the intermountain west

    NASA Astrophysics Data System (ADS)

    Harpold, Adrian; Brooks, Paul; Rajagopal, Seshadri; Heidbuchel, Ingo; Jardine, Angela; Stielstra, Clare

    2012-11-01

    Recent observations have documented declining snow water equivalent (SWE) and earlier melt in the coastal Cascade and Sierra Nevada mountain ranges, and climate models suggest that warming temperatures will decrease snowpack storage in the higher-elevation mountain ranges of interior western North America. To date, however, observations of changing SWE or snowmelt have been limited to the state of Colorado in the intermountain west (IMW), defined here as the Rio Grande, Colorado River, and Great Basins, which supply water to the driest regions of North America. We used daily SNOTEL data collected between 1984 and 2009 combined with the nonparametric regional Kendall test to demonstrate significant and widespread changes in the duration of snow cover in these river basins. Daily SNOTEL data demonstrated that basin average maximum SWE occurred as early as 7 March (Lower Colorado River Basin) and as late as 13 April (Upper Colorado, Yampa, and White River Basins). Although significant increases in winter temperature (T) were widespread, there were minimal changes in the day of maximum accumulation and no indications from SWE to winter precipitation ratios (SWE:P) and winter T observations that a transition from snow to rain had occurred. While there was little change in day of maximum accumulation, the duration of snow cover decreased in 11 of 13 drainage regions, and snowmelt center of mass (SM50) advanced 1 to 4 days per decade in 6 of 13 regions. There were significant trends toward a faster SM50 and shorter duration of snow cover in the highest-elevation regions (>2800 m) of the Colorado River Basin, suggesting that winter T and P may not be the primary driver of change. Our results show that the IMW hydroclimate is both spatially and temporally variable, with few changes in winter T and P in the Great Basin and drier and warmer winters in the Colorado River and Rio Grande Basins. The changes in snowmelt timing also were variable, with a shorter SM50 and less

  1. 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.

  2. 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

  3. 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.

  4. Ectoine accumulation in Brevibacterium epidermis.

    PubMed

    Onraedt, Annelies; De Muynck, Cassandra; Walcarius, Bart; Soetaert, Wim; Vandamme, Erick

    2004-10-01

    As a halotolerant bacterial species, Brevibacterium epidermis DSM 20659 can grow at relatively high salinity, tolerating up to 2 M NaCl. It synthesizes ectoine and the intracellular content increases with the medium salinity, with a maximum of 0.14 g ectoine/g CDW at 1 M NaCl. Sugar-stressed cells do not synthesize ectoine. Ectoine synthesis is also affected by the presence of external osmolytes. Added betaine is taken up and completely replaced ectoine, while L-proline is only temporarily accumulated after which ectoine is synthesized. The strain can metabolize ectoine; L-glutamate is a better carbon source for ectoine synthesis than L-aspartate.

  5. Phorbol esters modulate cyclic AMP accumulation in porcine thyroid cells

    SciTech Connect

    Emoto, T.; Kasai, K.; Hiraiwa, M.; Shimoda, S.

    1988-01-01

    In cultured porcine thyroid cells, during 60 min incubation phorbol 12-myristate 13-acetate (PMA) had no effect on basal cyclic AMP accumulation and slightly stimulated cyclic AMP accumulation evoked by thyroid stimulating hormone (TSH) or forskolin. Cholera toxin-induced cyclic AMP accumulation was significantly stimulated by PMA. On the other hand, cyclic AMP accumulation evoked by prostaglandin E/sub 1/ or E/sub 2/ (PGE/sub 1/ and PGE/sub 2/) was markedly depressed by simultaneous addition of PMA. These opposing effects of PMA on cyclic AMP accumulation evoked by PGE and cholera toxin were observed in a dose-related fashion, with half-maximal effect of around 10/sup -9/ M in either case. The almost same effects of PMA on cyclic AMP accumulation in basal and stimulated conditions were also observed in freshly prepared thyroid cells. The present study was performed in the presence of phosphodiesterase inhibitor, 3-iso-butyl-1-methylxanthine (IBMX), indicating that PMA affected adenylate cyclase activity. Therefore, it is suggested that PMA may modulate the production of cyclic AMP in response to different stimuli, possibly by affecting several sites in the adenylate cyclase complex in thyroid cells.

  6. Significant lexical relationships

    SciTech Connect

    Pedersen, T.; Kayaalp, M.; Bruce, R.

    1996-12-31

    Statistical NLP inevitably deals with a large number of rare events. As a consequence, NLP data often violates the assumptions implicit in traditional statistical procedures such as significance testing. We describe a significance test, an exact conditional test, that is appropriate for NLP data and can be performed using freely available software. We apply this test to the study of lexical relationships and demonstrate that the results obtained using this test are both theoretically more reliable and different from the results obtained using previously applied tests.

  7. 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

  8. Corrosion analysis of accumulative roll bonded aluminum 6016

    NASA Astrophysics Data System (ADS)

    Searcy, Jacquelyn Alisha

    Accumulative Roll Bonding is a Severe Plastic Deformation Process that is used to strengthen a material and promote grain refinement. Accumulative Roll Bonded Aluminum 6016 samples were investigated to determine their corrosion properties. The tests performed consisted of standard techniques including Cyclic Polarization Potentials, Exfoliation Corrosion (EXCO), Electrochemical Impedance Spectroscopy (EIS), Light Microscopy, and Electron Microprobe Analysis. From these tests, it was determined that for Al 6016, the Ultra Fine Grained samples obtained by Accumulative Roll Bonding are in general more susceptible to corrosion than the coarse grained sample. The higher corrosion rate was caused by the additional cold work, which increased the number of grain boundaries and rolled-in debris. The advantage however was that the corrosion was parallel to the surface and rather than deep into the sample as with the as-received 6016.

  9. Total carbon accumulation in a tropical forest landscape

    PubMed Central

    2012-01-01

    Background Regrowing tropical forests worldwide sequester important amounts of carbon and restore part of the C emissions emitted by deforestation. However, there are large uncertainties concerning the rates of carbon accumulation after the abandonment of agricultural and pasture land. We report here accumulation of total carbon stocks (TCS) in a chronosequence of secondary forests at a mid-elevation landscape (900-1200 m asl) in the Andean mountains of Colombia. Results We found positive accumulation rates for all ecosystem pools except soil carbon, which showed no significant trend of recovery after 36 years of secondary succession. We used these data to develop a simple model to predict accumulation of TCS over time. This model performed remarkably well predicting TCS at other chronosequences in the Americas (Root Mean Square Error < 40 Mg C ha-1), which provided an opportunity to explore different assumptions in the calculation of large-scale carbon budgets. Simulations of TCS with our empirical model were used to test three assumptions often made in carbon budgets: 1) the use of carbon accumulation in tree aboveground biomass as a surrogate for accumulation of TCS, 2) the implicit consideration of carbon legacies from previous land-use, and 3) the omission of landscape age in calculating accumulation rates of TCS. Conclusions Our simulations showed that in many situations carbon can be released from regrowing secondary forests depending on the amount of carbon legacies and the average age of the landscape. In most cases, the rates used to predict carbon accumulation in the Americas were above the rates predicted in our simulations. These biome level rates seemed to be realistic only in landscapes not affected by carbon legacies from previous land-use and mean ages of around 10 years. PMID:23249727

  10. Higher Education Exchange, 2012

    ERIC Educational Resources Information Center

    Brown, David W., Ed.; Witte, Deborah, Ed.

    2012-01-01

    "Higher Education Exchange" publishes case studies, analyses, news, and ideas about efforts within higher education to develop more democratic societies. Contributors to this issue of the "Higher Education Exchange" examine whether institutions of higher learning are doing anything to increase the capacity of citizens to shape their future.…

  11. Higher Education Exchange, 2010

    ERIC Educational Resources Information Center

    Brown, David W., Ed.; Witte, Deborah, Ed.

    2010-01-01

    "Higher Education Exchange" publishes case studies, analyses, news, and ideas about efforts within higher education to develop more democratic societies. Contributors to this issue of the "Higher Education Exchange" examine whether institutions of higher learning are doing anything to increase the capacity of citizens to shape their future.…

  12. Higher Education Exchange, 2008

    ERIC Educational Resources Information Center

    Brown, David W., Ed.; Witte, Deborah, Ed.

    2008-01-01

    "Higher Education Exchange" publishes case studies, analyses, news, and ideas about efforts within higher education to develop more democratic societies. Contributors to this issue of the "Higher Education Exchange" examine whether institutions of higher learning are doing anything to increase the capacity of citizens to shape their future.…

  13. Higher Education Exchange, 2014

    ERIC Educational Resources Information Center

    Brown, David W., Ed.; Witte, Deborah, Ed.

    2014-01-01

    Research shows that not only does higher education not see the public; when the public, in turn, looks at higher education, it sees mostly malaise, inefficiencies, expense, and unfulfilled promises. Yet, the contributors to this issue of the "Higher Education Exchange" tell of bright spots in higher education where experiments in working…

  14. Higher Education Exchange, 2004

    ERIC Educational Resources Information Center

    Brown, David W., Ed; Witte, Deborah, Ed.

    2004-01-01

    The Higher Education Exchange is part of a movement to strengthen higher education's democratic mission and foster a more democratic culture throughout American society. Working in this tradition, the Higher Education Exchange publishes case studies, analyses, news, and ideas about efforts within higher education to develop more democratic…

  15. Higher Education Exchange, 2005

    ERIC Educational Resources Information Center

    Brown, David W., Ed; Witte, Deborah, Ed.

    2005-01-01

    The "Higher Education Exchange" is part of a movement to strengthen higher education's democratic mission and foster a more democratic culture throughout American society. Working in this tradition, the "Higher Education Exchange" publishes case studies, analyses, news, and ideas about efforts within higher education to develop more democratic…

  16. Higher Education Exchange, 2011

    ERIC Educational Resources Information Center

    Brown, David W., Ed.; Witte, Deborah, Ed.

    2011-01-01

    "Higher Education Exchange" publishes case studies, analyses, news, and ideas about efforts within higher education to develop more democratic societies. Contributors to this issue of the "Higher Education Exchange" examine whether institutions of higher learning are doing anything to increase the capacity of citizens to shape their future.…

  17. Significance of brown dwarfs

    NASA Technical Reports Server (NTRS)

    Black, D. C.

    1986-01-01

    The significance of brown dwarfs for resolving some major problems in astronomy is discussed. The importance of brown dwarfs for models of star formation by fragmentation of molecular clouds and for obtaining independent measurements of the ages of stars in binary systems is addressed. The relationship of brown dwarfs to planets is considered.

  18. Statistical Significance Testing.

    ERIC Educational Resources Information Center

    McLean, James E., Ed.; Kaufman, Alan S., Ed.

    1998-01-01

    The controversy about the use or misuse of statistical significance testing has become the major methodological issue in educational research. This special issue contains three articles that explore the controversy, three commentaries on these articles, an overall response, and three rejoinders by the first three authors. They are: (1)…

  19. Guidelines for Waste Accumulation Areas (WAAs)

    SciTech Connect

    Not Available

    1991-07-01

    The purpose of this document is to set conditions for establishing and maintaining areas for the accumulation of hazardous waste at LBL. Areas designed for accumulation of these wastes in quantities greater than 100 kg (220 lb) per month of solid waste or 55 gallons per month of liquid waste are called Waste Accumulation Areas (WAAs). Areas designed for accumulation of wastes in smaller amounts are called Satellite Accumulation Areas (SAAs). This document provides guidelines for employee and organizational responsibilities for WAAs; constructing a WAA; storing waste in a WAA; operating and maintaining a WAA, and responding to spills in a WAA. 4 figs.

  20. 10Be accumulation in a soil chronosequence

    USGS Publications Warehouse

    Pavich, M.J.; Brown, L.; Klein, J.; Middleton, R.

    1984-01-01

    We have measured the concentration of the cosmogenic isotope 10Be in soil samples from various horizons at six sites, including three independently dated Rappahannock River terraces and a previously undated Piedmont soil to which we have assigned an age. All of the incident 10Be can be accounted for in one of these soils and a second is within a factor of two. In three soils, whose concentrations vary widely with depth, a significant fraction of the incident 10Be cannot be accounted for. Incomplete sampling, and enhanced Be mobility caused by organic components, are the probable reasons for the low inventory of Be from these three soils. Overall, the data from these six sites indicate that 10Be accumulation could be used to assign ages to soils if Be is not mobilized and lost from the soil profile. ?? 1984.

  1. Surfactants differentially impact p,p'-DDE accumulation by plant and earthworm species.

    PubMed

    White, Jason C; Peters, Richard; Kelsey, Jason W

    2007-04-15

    The effect of four surfactants (Triton X-100, Tween-80, rhamnolipids, cyclodextrin) at 100-1000 mg/L on p,p'-DDE phytoextraction by Cucurbita pepo (zucchini) under field conditions and p,p'-DDE bioaccumulation by earthworm species (Eisenia fetida, Lumbricus terrestris) under laboratory conditions was investigated. Abiotically, surfactants (except cyclodextrin) increased contaminant desorption from soil by 4-fold, with higher concentrations generally promoting greater release. Cyclodextrin had no effect on DDE desorption. DDE concentrations in unamended zucchini roots and stems were 30- and 7.8-fold greater than soil levels, respectively, and 1.6% of the contaminant was extracted from the soil. The surfactant effects were cultivar specific. Triton X-100 increased DDE uptake in "Costata" by 2.6-fold, yielding 5% contaminant phytoextraction. In "Goldrush", DDE accumulation decreased by 69% across all surfactants. Surfactants significantly increased DDE bioaccumulation by earthworms. For E. fetida with all surfactants and L. terrestriswith Triton X-100 and cyclodextrin, DDE accumulation increased 2.5-7.2-fold, paralleling abiotic desorption. However, Tween-80 and rhamnolipids increased DDE accumulation in L. terrestris by 74 and 36 fold, respectively. These dramatic increases in contaminant bioaccumulation do not correlate with the increased availability observed abiotically. Surfactant-mediated increases in contaminant bioavailability are an unexpectedly complex process and clearly present unanticipated concerns over pollutant exposure to nontarget organisms. PMID:17533859

  2. Biofilm formation on polystyrene in detached vs. planktonic cells of polyhydroxyalkanoate-accumulating Halomonas venusta.

    PubMed

    Berlanga, Mercedes; Domènech, Òscar; Guerrero, Ricardo

    2014-12-01

    Biofilm development is characterized by distinct stages of initial attachment, microcolony formation and maturation (sessile cells), and final detachment (dispersal of new, planktonic cells). In this work we examined the influence of polyhydroxyalkanoate (PHA) accumulation on bacterial surface properties and biofilm formation on polystyrene in detached vs. planktonic cells of an environmental strain isolated from microbial mats, Halomonas venusta MAT28. This strain was cultured either in an artificial biofilm in which the cells were immobilized on alginate beads (sessile) or as free-swimming (planktonic) cells. For the two modes of growth, conditions allowing or preventing PHA accumulation were established. Cells detached from alginate beads and their planktonic counterparts were used to study cell surface properties and cellular adhesion on polystyrene. Detached cells showed a slightly higher affinity than planktonic cells for chloroform (Lewis-acid) and a greater hydrophobicity (affinity for hexadecane and hexane). Those surface characteristics of the detached cells may explain their better adhesion on polystyrene compared to planktonic cells. Adhesion to polystyrene was not significantly different between H. venusta cells that had accumulated PHA vs. those that did not. These observations suggest that the surface properties of detached cells clearly differ from those of planktonic cells and that for at least the first 48 h after detachment from alginate beads H. venusta retained the capacity of sessile cells to adhere to polystyrene and to form a biofilm. PMID:26421734

  3. 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.

  4. Unprecedented last-glacial mass accumulation rates determined by luminescence dating of loess from western Nebraska

    USGS Publications Warehouse

    Roberts, H.M.; Muhs, D.R.; Wintle, A.G.; Duller, G.A.T.; Bettis, E. Arthur

    2003-01-01

    A high-resolution chronology for Peoria (last glacial period) Loess from three sites in Nebraska, midcontinental North America, is determined by applying optically stimulated luminescence (OSL) dating to 35-50 ??m quartz. At Bignell Hill, Nebraska, an OSL age of 25,000 yr near the contact of Peoria Loess with the underlying Gilman Canyon Formation shows that dust accumulation occurred early during the last glacial maximum (LGM), whereas at Devil's Den and Eustis, Nebraska, basal OSL ages are significantly younger (18,000 and 21,000 yr, respectively). At all three localities, dust accumulation ended at some time after 14,000 yr ago. Mass accumulation rates (MARs) for western Nebraska, calculated using the OSL ages, are extremely high from 18,000 to 14,000 yr-much higher than those calculated for any other pre-Holocene location worldwide. These unprecedented MARs coincide with the timing of a mismatch between paleoenvironmental evidence from central North America, and the paleoclimate simulations from atmospheric global circulation models (AGCMs). We infer that the high atmospheric dust loading implied by these MARs may have played an important role, through radiative forcing, in maintaining a colder-than-present climate over central North America for several thousand years after summer insolation exceeded present-day values. ?? 2003 Elsevier Science (USA). All rights reserved.

  5. 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

  6. 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.

  7. Trace metal accumulation in soil and their phytoavailability as affected by greenhouse types in north China.

    PubMed

    Yang, Lanqin; Huang, Biao; Mao, Mingcui; Yao, Lipeng; Hickethier, Martina; Hu, Wenyou

    2015-05-01

    Long-term heavy organic fertilizer application has linked greenhouse vegetable production (GVP) with trace metal contamination in north China. Given that trace metals release from fertilizers and their availability may be affected by discrepant environmental conditions, especially temperature under different greenhouses, this study investigated Cd, Cu, Pb, and Zn accumulation and contamination extent in soil as well as their phytoavailability under two major greenhouses in Tongshan, north China, namely solar greenhouse (SG) and round-arched plastic greenhouse (RAPG), to evaluate their presumed difference. The results showed significant Cd, Cu, Pb, and Zn accumulation in GVP soil by comparing with those in open-field soil, but their accumulation extent and rates were generally greater in SG than those in RAPG. This may be related to more release of trace metals to soil due to the acceleration of decomposition and humification process of organic fertilizers under higher soil temperature in SG relative to that in RAPG. Overall, soil in both greenhouses was generally less polluted or moderately polluted by the study metals. Similarly, decreased soil pH and elevated soil available metals in SG caused higher trace metals in leaf vegetables in SG than those in RAPG, although there was no obvious risk via vegetable consumption under both greenhouses. Lower soil pH may be predominantly ascribed to more intensive farming practices in SG while elevated soil available metals may be attributed to more release of dissolved organic matter-metal complexes from soil under higher temperature in SG. The data provided in this study may assist in developing reasonable and sustainable fertilization strategies to abate trace metal contamination in both greenhouses.

  8. Artificial breakwaters as garbage bins: Structural complexity enhances anthropogenic litter accumulation in marine intertidal habitats.

    PubMed

    Aguilera, Moisés A; Broitman, Bernardo R; Thiel, Martin

    2016-07-01

    Coastal urban infrastructures are proliferating across the world, but knowledge about their emergent impacts is still limited. Here, we provide evidence that urban artificial reefs have a high potential to accumulate the diverse forms of litter originating from anthropogenic activities around cities. We test the hypothesis that the structural complexity of urban breakwaters, when compared with adjacent natural rocky intertidal habitats, is a driver of anthropogenic litter accumulation. We determined litter abundances at seven sites (cities) and estimated the structural complexity in both urban breakwaters and adjacent natural habitats from northern to central Chile, spanning a latitudinal gradient of ∼15° (18°S to 33°S). Anthropogenic litter density was significantly higher in coastal breakwaters when compared to natural habitats (∼15.1 items m(-2) on artificial reefs versus 7.4 items m(-2) in natural habitats) at all study sites, a pattern that was temporally persistent. Different litter categories were more abundant on the artificial reefs than in natural habitats, with local human population density and breakwater extension contributing to increase the probabilities of litter occurrence by ∼10%. In addition, structural complexity was about two-fold higher on artificial reefs, with anthropogenic litter density being highest at intermediate levels of structural complexity. Therefore, the spatial structure characteristic of artificial reefs seems to enhance anthropogenic litter accumulation, also leading to higher residence time and degradation potential. Our study highlights the interaction between coastal urban habitat modification by establishment of artificial reefs, and pollution. This emergent phenomenon is an important issue to be considered in future management plans and the engineering of coastal ecosystems. PMID:27149151

  9. Artificial breakwaters as garbage bins: Structural complexity enhances anthropogenic litter accumulation in marine intertidal habitats.

    PubMed

    Aguilera, Moisés A; Broitman, Bernardo R; Thiel, Martin

    2016-07-01

    Coastal urban infrastructures are proliferating across the world, but knowledge about their emergent impacts is still limited. Here, we provide evidence that urban artificial reefs have a high potential to accumulate the diverse forms of litter originating from anthropogenic activities around cities. We test the hypothesis that the structural complexity of urban breakwaters, when compared with adjacent natural rocky intertidal habitats, is a driver of anthropogenic litter accumulation. We determined litter abundances at seven sites (cities) and estimated the structural complexity in both urban breakwaters and adjacent natural habitats from northern to central Chile, spanning a latitudinal gradient of ∼15° (18°S to 33°S). Anthropogenic litter density was significantly higher in coastal breakwaters when compared to natural habitats (∼15.1 items m(-2) on artificial reefs versus 7.4 items m(-2) in natural habitats) at all study sites, a pattern that was temporally persistent. Different litter categories were more abundant on the artificial reefs than in natural habitats, with local human population density and breakwater extension contributing to increase the probabilities of litter occurrence by ∼10%. In addition, structural complexity was about two-fold higher on artificial reefs, with anthropogenic litter density being highest at intermediate levels of structural complexity. Therefore, the spatial structure characteristic of artificial reefs seems to enhance anthropogenic litter accumulation, also leading to higher residence time and degradation potential. Our study highlights the interaction between coastal urban habitat modification by establishment of artificial reefs, and pollution. This emergent phenomenon is an important issue to be considered in future management plans and the engineering of coastal ecosystems.

  10. 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.

  11. Interaction of functionalized fullerenes and metal accumulation in Daphnia magna.

    PubMed

    Yu, Zhi-Guo; Wang, Wen-Xiong

    2014-05-01

    In aquatic environments, transformation of pollutants by association with functionalized carbon-based nanoparticles can dramatically change their cycling pathways. The present study quantified the uptake and depuration behavior of cadmium and zinc bound with functionalized fullerene nanoparticles (f-nC(60)) in a freshwater cladoceran, Daphnia magna, in a well-dispersed medium. Metal uptake proceeded with a linear pattern during the 8-h exposure period, and the uptake rate constants (ku) were 1.3-fold to 1.4-fold higher for Cd or comparable for Zn bound with f-nC(60) than those of the free ones. The assimilation efficiencies of Cd and Zn bound with f-nC(60) were significantly enhanced when compared with those metals bound with algal food. Furthermore, the depuration of metals bound with f-nC(60) was relatively slower compared to the depuration of metals bound with carbon nanotubes. A longer exposure to f-nC(60) resulted in an even slower depuration of metals. The authors conclude that metal binding with f-nC(60) as modified nanoparticles could serve as a new pathway for the elevated metal accumulation in Daphnia.

  12. 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.

  13. 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.

  14. Overexpressing GSH1 and AsPCS1 simultaneously increases the tolerance and accumulation of cadmium and arsenic in Arabidopsis thaliana.

    PubMed

    Guo, Jiangbo; Dai, Xiaojing; Xu, Wenzhong; Ma, Mi

    2008-07-01

    The goal of this study was to develop transgenic plants with increased tolerance for and accumulation of heavy metals and metalloids from soil by simultaneous overexpression of AsPCS1 and GSH1 (derived from garlic and baker's yeast) in Arabidopsis thaliana. Phytochelatins (PCs) and glutathione (GSH) are the main binding peptides involved in chelating heavy metal ions in plants and other living organisms. Single-gene transgenic lines had higher tolerance to and accumulated more Cd and As than wild-type. Compared to single-gene transgenic lines, dual-gene transformants exhibited significantly higher tolerance to and accumulated more Cd and As. One of the dual-gene transgenic lines, PG1, accumulated twice the amount of Cd as single-gene transgenic lines. Simultaneous overexpression of AsPCS1 and GSH1 led to elevated total PC production in transgenic Arabidopsis. These results indicate that such a stacking of modified genes is capable of increasing Cd and As tolerance and accumulation in transgenic lines, and represents a highly promising new tool for use in phytoremediation efforts.

  15. Accumulation and distribution of iron, cadmium, lead and nickel in cucumber plants grown in hydroponics containing two different chelated iron supplies.

    PubMed

    Csog, Árpád; Mihucz, Victor G; Tatár, Eniko; Fodor, Ferenc; Virág, István; Majdik, Cornelia; Záray, Gyula

    2011-07-01

    Cucumber plants grown in hydroponics containing 10 μM Cd(II), Ni(II) and Pb(II), and iron supplied as Fe(III) EDTA or Fe(III) citrate in identical concentrations, were investigated by total-reflection X-ray fluorescence spectrometry with special emphasis on the determination of iron accumulation and distribution within the different plant compartments (root, stem, cotyledon and leaves). The extent of Cd, Ni and Pb accumulation and distribution were also determined. Generally, iron and heavy-metal contaminant accumulation was higher when Fe(III) citrate was used. The accumulation of nickel and lead was higher by about 20% and 100%, respectively, if the iron supply was Fe(III) citrate. The accumulation of Cd was similar. In the case of Fe(III) citrate, the total amounts of Fe taken up were similar in the control and heavy-metal-treated plants (27-31 μmol/plant). Further, the amounts of iron transported from the root towards the shoot of the control, lead- and nickel-contaminated plants were independent of the iron(III) form. Although Fe mobility could be characterized as being low, its distribution within the shoot was not significantly affected by the heavy metals investigated.

  16. Dietary Deficiency of Calcium and/or Iron, an Age-Related Risk Factor for Renal Accumulation of Cadmium in Mice.

    PubMed

    Min, Kyong-Son; Sano, Erika; Ueda, Hidenori; Sakazaki, Fumitoshi; Yamada, Keita; Takano, Masaoki; Tanaka, Keiichi

    2015-01-01

    The major route of cadmium (Cd) intake by non-smokers is through food ingestion. Cd is a non-essential metal absorbed through one or more transporters of essential metal ions. Expression of these transporters is affected by nutritional status. To investigate the risk factors for Cd toxicity, the effects of deficiency of essential metals on hepatic and renal accumulation of Cd were studied in mice of different ages. Mice were administered a control diet or one of the essential metal-deficient diets, administered Cd by gavage for 6 weeks, and killed; then, Cd accumulation was evaluated. Iron deficiency (FeDF) or calcium deficiency (CaDF) resulted in remarkable increases in hepatic and renal Cd accumulation compared with control-diet mice and other essential metal-deficient mice. Cd accumulation in hepatic and renal tissue was increased significantly at all ages tested in FeDF and CaDF mice. Renal Cd concentrations were higher in 4-week-old mice than in 8- and 25-week-old mice. Increase in intestinal mRNA expression of calcium transporter (CaT)1, divalent metal ion transporter-1, and metallothionein (MT)1 was also higher in 4-week-old mice than in other mice. Renal accumulation of Cd showed strong correlation with intestinal mRNA expression of CaT1 and MT1. These data suggest that CaDF and FeDF at younger ages can be a risk factor for Cd toxicity.

  17. Effects of Waterborne Lead Exposure in Mozambique Tilapia: Oxidative Stress, Osmoregulatory Responses, and Tissue Accumulation.

    PubMed

    Kaya, Hasan; Akbulut, Mehmet

    2015-06-01

    We studied the oxidative stress and osmoregulatory damage as well as the accumulation of lead in Mozambique Tilapia Oreochromis mossambicus exposed to different sublethal concentrations-low, medium, and high (0.5, 2.5, and 5.0 mg/L)-of waterborne lead for 14 d in a semistatic condition. The accumulated levels of Na⁺, K⁺-ATPase, glutathione (GSH), and thiobarbituric acid reactive substances (TBARS) were determined from samples of gill, liver, intestine, brain, kidney, and muscle tissues. At the end of the experiment, the GSH levels of most tissues were higher in the treated group than in the control group (especially in the liver and kidney) but lower in the intestine. The levels of TBARS in the gill and brain tissues of the fish exposed to high lead doses were significantly higher than those of fish in the control group. Na⁺, K⁺-ATPase activity seemed to be significantly inhibited in the gill, intestine, and brain tissues across all treatment groups. At the end of the study, the total amount of lead that had accumulated within the various tissues ranked as follows: intestines > kidney > brain > gill > liver > muscle. Our findings suggest that sublethal concentrations of lead can disrupt the health of Mozambique Tilapia and cause oxidative stress and osmoregulatory damage.

  18. Damage production and accumulation in SiC structures in inertial and magnetic fusion systems

    NASA Astrophysics Data System (ADS)

    Sawan, M. E.; Ghoniem, N. M.; Snead, L.; Katoh, Y.

    2011-10-01

    Radiation damage parameters in SiC/SiC composite structures are determined in both magnetic (MFE) and inertial (IFE) confinement fusion systems. Variations in the geometry, neutron energy spectrum, and pulsed nature of neutron production result in significant differences in damage parameters between the two systems. With the same neutron wall loading, the displacement damage rate in the first wall in an IFE system is ˜10% lower than in an MFE system, while gas production and burnup rates are a factor of 2 lower. Self-cooled LiPb and Flibe blankets were analyzed. While using LiPb results in higher displacement damage, Flibe yields higher gas production and burnup rates. The effects of displacement damage and helium production on defect accumulation in SiC/SiC composites are also discussed.

  19. 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.

  20. Iron Accumulation During Cellular Senescence in Human Fibroblasts In Vitro

    PubMed Central

    KILLILEA, DAVID W.; ATAMNA, HANI; LIAO, CHARLES; AMES, BRUCE N.

    2015-01-01

    Iron accumulates as a function of age in several tissues in vivo and is associated with the pathology of numerous age-related diseases. The molecular basis of this change may be due to a loss of iron homeostasis at the cellular level. Therefore, changes in iron content in primary human fibroblast cells (IMR-90) were studied in vitro as a model of cellular senescence. Total iron content increased exponentially during cellular senescence, resulting in 10-fold higher levels of iron compared with young cells. Low-dose hydrogen peroxide (H2O2) induced early senescence in IMR-90s and concomitantly accelerated iron accumulation. Furthermore, senescence-related and H2O2-stimulated iron accumulation was attenuated by N-tert-butylhydroxylamine (NtBHA), a mitochondrial antioxidant that delays senescence in vitro. However, SV40-transformed, immortalized IMR-90s showed no time-dependent changes in metal content in culture or when treated with H2O2 and/or NtBHA. These data indicate that iron accumulation occurs during normal cellular senescence in vitro. This accumulation of iron may contribute to the increased oxidative stress and cellular dysfunction seen in senescent cells. PMID:14580305

  1. Lysosomal Cholesterol Accumulation Sensitizes To Acetaminophen Hepatotoxicity by Impairing Mitophagy

    PubMed Central

    Baulies, Anna; Ribas, Vicent; Núñez, Susana; Torres, Sandra; Alarcón-Vila, Cristina; Martínez, Laura; Suda, Jo; Ybanez, Maria D.; Kaplowitz, Neil; García-Ruiz, Carmen; Fernández-Checa, Jose C.

    2015-01-01

    The role of lysosomes in acetaminophen (APAP) hepatotoxicity is poorly understood. Here, we investigated the impact of genetic and drug-induced lysosomal cholesterol (LC) accumulation in APAP hepatotoxicity. Acid sphingomyelinase (ASMase)−/− mice exhibit LC accumulation and higher mortality after APAP overdose compared to ASMase+/+ littermates. ASMase−/− hepatocytes display lower threshold for APAP-induced cell death and defective fusion of mitochondria-containing autophagosomes with lysosomes, which decreased mitochondrial quality control. LC accumulation in ASMase+/+ hepatocytes caused by U18666A reproduces the susceptibility of ASMase−/− hepatocytes to APAP and the impairment in the formation of mitochondria-containing autolysosomes. LC extraction by 25-hydroxycholesterol increased APAP-mediated mitophagy and protected ASMase−/− mice and hepatocytes against APAP hepatotoxicity, effects that were reversed by chloroquine to disrupt autophagy. The regulation of LC by U18666A or 25-hydroxycholesterol did not affect total cellular sphingomyelin content or its lysosomal distribution. Of relevance, amitriptyline-induced ASMase inhibition in human hepatocytes caused LC accumulation, impaired mitophagy and increased susceptibility to APAP. Similar results were observed upon glucocerebrosidase inhibition by conduritol β-epoxide, a cellular model of Gaucher disease. These findings indicate that LC accumulation determines susceptibility to APAP hepatotoxicity by modulating mitophagy, and imply that genetic or drug-mediated ASMase disruption sensitizes to APAP-induced liver injury. PMID:26657973

  2. Lysosomal Cholesterol Accumulation Sensitizes To Acetaminophen Hepatotoxicity by Impairing Mitophagy.

    PubMed

    Baulies, Anna; Ribas, Vicent; Núñez, Susana; Torres, Sandra; Alarcón-Vila, Cristina; Martínez, Laura; Suda, Jo; Ybanez, Maria D; Kaplowitz, Neil; García-Ruiz, Carmen; Fernández-Checa, Jose C

    2015-12-11

    The role of lysosomes in acetaminophen (APAP) hepatotoxicity is poorly understood. Here, we investigated the impact of genetic and drug-induced lysosomal cholesterol (LC) accumulation in APAP hepatotoxicity. Acid sphingomyelinase (ASMase)(-/-) mice exhibit LC accumulation and higher mortality after APAP overdose compared to ASMase(+/+) littermates. ASMase(-/-) hepatocytes display lower threshold for APAP-induced cell death and defective fusion of mitochondria-containing autophagosomes with lysosomes, which decreased mitochondrial quality control. LC accumulation in ASMase(+/+) hepatocytes caused by U18666A reproduces the susceptibility of ASMase(-/-) hepatocytes to APAP and the impairment in the formation of mitochondria-containing autolysosomes. LC extraction by 25-hydroxycholesterol increased APAP-mediated mitophagy and protected ASMase(-/-) mice and hepatocytes against APAP hepatotoxicity, effects that were reversed by chloroquine to disrupt autophagy. The regulation of LC by U18666A or 25-hydroxycholesterol did not affect total cellular sphingomyelin content or its lysosomal distribution. Of relevance, amitriptyline-induced ASMase inhibition in human hepatocytes caused LC accumulation, impaired mitophagy and increased susceptibility to APAP. Similar results were observed upon glucocerebrosidase inhibition by conduritol β-epoxide, a cellular model of Gaucher disease. These findings indicate that LC accumulation determines susceptibility to APAP hepatotoxicity by modulating mitophagy, and imply that genetic or drug-mediated ASMase disruption sensitizes to APAP-induced liver injury.

  3. ACCUMULATION OF METHYLMERCURY OR POLYCHLORINATED BIPHENYLS IN IN VITRO MODELS OF RAT NEURONAL TISSUE.

    EPA Science Inventory

    This manuscript reports data examining the accumulation of PCBs or methylmercury into the tissue of three commonly used in vitro neuronal models.

    ? The results demonstrate that these lipophilic compounds can accumulate to levels 5 to 100 fold higher than the surrounding s...

  4. Significant Tsunami Events

    NASA Astrophysics Data System (ADS)

    Dunbar, P. K.; Furtney, M.; McLean, S. J.; Sweeney, A. D.

    2014-12-01

    Tsunamis have inflicted death and destruction on the coastlines of the world throughout history. The occurrence of tsunamis and the resulting effects have been collected and studied as far back as the second millennium B.C. The knowledge gained from cataloging and examining these events has led to significant changes in our understanding of tsunamis, tsunami sources, and methods to mitigate the effects of tsunamis. The most significant, not surprisingly, are often the most devastating, such as the 2011 Tohoku, Japan earthquake and tsunami. The goal of this poster is to give a brief overview of the occurrence of tsunamis and then focus specifically on several significant tsunamis. There are various criteria to determine the most significant tsunamis: the number of deaths, amount of damage, maximum runup height, had a major impact on tsunami science or policy, etc. As a result, descriptions will include some of the most costly (2011 Tohoku, Japan), the most deadly (2004 Sumatra, 1883 Krakatau), and the highest runup ever observed (1958 Lituya Bay, Alaska). The discovery of the Cascadia subduction zone as the source of the 1700 Japanese "Orphan" tsunami and a future tsunami threat to the U.S. northwest coast, contributed to the decision to form the U.S. National Tsunami Hazard Mitigation Program. The great Lisbon earthquake of 1755 marked the beginning of the modern era of seismology. Knowledge gained from the 1964 Alaska earthquake and tsunami helped confirm the theory of plate tectonics. The 1946 Alaska, 1952 Kuril Islands, 1960 Chile, 1964 Alaska, and the 2004 Banda Aceh, tsunamis all resulted in warning centers or systems being established.The data descriptions on this poster were extracted from NOAA's National Geophysical Data Center (NGDC) global historical tsunami database. Additional information about these tsunamis, as well as water level data can be found by accessing the NGDC website www.ngdc.noaa.gov/hazard/

  5. Temporal Patterns of Snow Accumulation and the Effect of Nearby Summit, Greenland

    NASA Astrophysics Data System (ADS)

    Kelson, J.; Hawley, R. L.; Lutz, E.

    2012-12-01

    The mass balance of a glacier reflects how the mass of the ice sheet changes over time, which reflects climate change and could affect sea level rise. The rate at which snow accumulates is essential for calculating the mass balance of the Greenland ice sheet. We examine the accumulation measured monthly from 2006 to 2011 at 121 stakes in a stepping line near Summit, Greenland. We investigate the temporal patterns in accumulation with a monthly resolution. We find that seasonally, September experiences the most accumulation. We also determine that there is no significant change in accumulation rates over the study period. We then examine the spatial patterns of accumulation in order to determine if the accumulation record from the stakes can be considered an accurate estimate for regional accumulation patterns. We find that the accumulation surface is very smooth at our sampling scale; there are no ridge or trough features that might cause unrepresentative data. However, the stake line experiences increased accumulation in the South, which may be a snowdrift caused by the structures of nearby Summit Camp. Considering the possibility of drift from Summit, the accumulation measurements near the southern end of the stake line cannot be used as a regional estimate for accumulation.

  6. 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

  7. 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

  8. [Chemical characteristics of the rhizosphere soil of water spinach cultivars differing in Cd accumulation].

    PubMed

    Gong, Yu-Lian; Yang, Zhong-Yi

    2014-08-01

    A rhizobox experiment was conducted to investigate the chemical characteristics of the rhizosphere soils of two water spinach cultivars differing in Cd accumulation, QLQ (a low-Cd cultivar) and T308 (a high-Cd cultivar). The results showed that the diethylenetriamine pentacetate acid extractable Cd (DTPA-Cd) concentration in the rhizos-phere soil of QLQ was significantly higher than that of T308 (P < 0.05). pH and Eh in the rhizosphere soil of QLQ were significantly higher than those of T308 (P < 0.05), while EC was opposite. Contents of organic matter and dissolved organic matter (DOM) in the rhizosphere soil of QLQ were both higher than those of T308. In contaminated soil, the composition and concentration of low molecular weight organic acids in the rhizosphere between the two cultivars were both different. Acetic, propionic, citric and fumaric acids were detected in the rhizosphere soil of T308, and only citric and fumaric acids were detected in that of QLQ. The total concentration of low molecular weight organic acids in the rhizosphere soil of QLQ (1.93 nmol x g(-1) DM) was lower than that of T308 (15.11 nmol x g(-1) DM) (P < 0.01). Compared with the high-Cd cultivar (T308), the chemical characteristics of the rhizosphere soil of the low-Cd cultivar (QLQ) were obviously distinct, i. e., the relatively higher content of organic matter, the lower content of low molecular weight organic acids with a specific composition, less acidification of soil, and a lower ability in reduction, correspondingly lowering the mobility of Cd in soil and reducing Cd accumulation by plant.

  9. Tales of significance.

    PubMed

    Bell, Graham

    2016-01-01

    In this experiment, the authors were interested in testing the effect of a small molecule inhibitor on the ratio of males and females in the offspring of their model Dipteran species. The authors report that in a wild-type population, ~50 % of offspring are male. They then test the effect of treating females with the chemical, which they think might affect the male:female ratio compared with the untreated group. They claim that there is a statistically significant increase in the percentage of males produced and conclude that the drug affects sex ratios. PMID:27338560

  10. Delayed hyperoxic ventilation attenuates oxygen-induced free radical accumulation during early reperfusion after global brain ischemia.

    PubMed

    Wang, Yan; Yuan, Li; Liu, Ping; Zhao, Min

    2015-02-11

    To compare the effect of immediate and delayed administration of oxygen on the accumulation of free radicals in ischemia-reperfusion animal models. Thirty-two adult male Mongolian gerbils with microdialysis probes implanted in the right hippocampal CA1 were divided randomly into four groups (eight each). One group was sham-operated (Sham group) whereas the other three groups were subjected to 10 min bilateral carotid artery occlusion (BCAO). BCAO-treated animals were then subjected to the following: (a) immediate 30% O2 (near normoxia, NO group), (b) immediate 100% O2 (hyperoxia, HO group), and (c) 30% O2 for 60 min, followed by 100% O2 for 60 min (delayed hyperoxia, DHO group). Hippocampal accumulation of hydroxyl radicals (•OH) during reperfusion was estimated by measuring 2,3-dihydroxybenzoic acid (DHBA) and 2,5-DHBA in microdialysis perfusate. Hippocampi were removed 2 h after perfusion to measure malondialdehyde, pyruvate dehydrogenase activity, indices of lipid peroxidation, and cellular respiration. At 24 h after BCAO, the histology of hippocampi was analyzed to rate the injury. Immediately after the onset of reperfusion, all groups showed markedly elevated DHBA, which returned to baseline over 1-2 h. Compared with the NO group, the HO group showed significantly higher peak DHBA and slower recovery. In contrast, the DHO group was not significantly different from the NO group in terms of the DHBA level. DHO animals also showed significantly lower hippocampal malondialdehyde accumulation and higher pyruvate dehydrogenase activity at 2 h after reperfusion versus the HO group. Histology analysis also showed animals in the DHO group with ameliorated injury compared with the HO group. Hydroxyl radical accumulation was more sensitive to O2 during early reperfusion. Delayed hyperoxia may re-establish oxidative metabolism while minimizing oxidative stress after CA.

  11. [Effect of long-term fertilization on lignin accumulation in typical subtropical upland soil].

    PubMed

    Feng, Shu-zhen; Chen, Xiang-bi; He, Xun-yang; Dong, Ming-zhe; Qiu, Hu-sen; Su, Yi-rong

    2015-01-01

    To investigate the effect of long-term fertilization on lignin accumulation and clarify its influencing factors in subtropical agricultural upland soils, alkaline CuO oxidation and gas chromatography was performed to quantify the amount of lignin and its monomers components (V, S and C). The soil samples were collected from the fertilization treatments of NPK and NPKS (NPK combined with straw) in Huanjiang County, Guangxi Province (limestone soil) and Taoyuan County, Hunan Province (red soil). The results showed that NPK had no significant effect on the lignin content (Sumvsc) of limestone soil, whereas the content in red soil significantly increased by (55 ± 1)%. For the NPKS treatment, the lignin content in limestone and red soil increased by (328 ± 4)% and (456 ± 9)%, respectively. After the same fertilization treatment, the proportion of cinnamyl (C)-type significantly increased in red soil, while a significant increase of vanillyl (V)-type monomers occurred in limestone soil, indicating that lignin degradation in agricultural soils was monomer specific. Furthermore, the acid-to-aldehyde ratios of syringyl-type [(Ac/Al)] or vanillyl-type [(Ac/Al)v] monomers tended to decrease after long-term fertilization with the higher value for limestone soil, suggesting the degree of lignin degradation in limestone was higher than that in red soil. Soil organic matter and total nitrogen were not correlated with lignin content, but were significantly correlated with the composition of VSC monomers. Meanwhile, the available nutrient content in the soil (available nitrogen, phosphorus, and potassium) was closely related to the contents and components of V, S, and C-type monomers (P<0.05). It indicated that the availability of soil nutrition should be considered as a key factor for the accumulation of lignin. PMID:25985658

  12. [Effect of long-term fertilization on lignin accumulation in typical subtropical upland soil].

    PubMed

    Feng, Shu-zhen; Chen, Xiang-bi; He, Xun-yang; Dong, Ming-zhe; Qiu, Hu-sen; Su, Yi-rong

    2015-01-01

    To investigate the effect of long-term fertilization on lignin accumulation and clarify its influencing factors in subtropical agricultural upland soils, alkaline CuO oxidation and gas chromatography was performed to quantify the amount of lignin and its monomers components (V, S and C). The soil samples were collected from the fertilization treatments of NPK and NPKS (NPK combined with straw) in Huanjiang County, Guangxi Province (limestone soil) and Taoyuan County, Hunan Province (red soil). The results showed that NPK had no significant effect on the lignin content (Sumvsc) of limestone soil, whereas the content in red soil significantly increased by (55 ± 1)%. For the NPKS treatment, the lignin content in limestone and red soil increased by (328 ± 4)% and (456 ± 9)%, respectively. After the same fertilization treatment, the proportion of cinnamyl (C)-type significantly increased in red soil, while a significant increase of vanillyl (V)-type monomers occurred in limestone soil, indicating that lignin degradation in agricultural soils was monomer specific. Furthermore, the acid-to-aldehyde ratios of syringyl-type [(Ac/Al)] or vanillyl-type [(Ac/Al)v] monomers tended to decrease after long-term fertilization with the higher value for limestone soil, suggesting the degree of lignin degradation in limestone was higher than that in red soil. Soil organic matter and total nitrogen were not correlated with lignin content, but were significantly correlated with the composition of VSC monomers. Meanwhile, the available nutrient content in the soil (available nitrogen, phosphorus, and potassium) was closely related to the contents and components of V, S, and C-type monomers (P<0.05). It indicated that the availability of soil nutrition should be considered as a key factor for the accumulation of lignin.

  13. 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 microg/g). The isomer profile in eggs was not significantly different from that of adults, suggesting that the maternal transfer of branched and linear PFOS isomers in fish is largely nonisomer specific.

  14. Geographic variability in organic carbon stock and accumulation rate in sediments of East and Southeast Asian seagrass meadows

    NASA Astrophysics Data System (ADS)

    Miyajima, Toshihiro; Hori, Masakazu; Hamaguchi, Masami; Shimabukuro, Hiromori; Adachi, Hiroshi; Yamano, Hiroya; Nakaoka, Masahiro

    2015-04-01

    Organic carbon (OC) stored in the sediments of seagrass meadows has been considered a globally significant OC reservoir. However, the sparsity and regional bias of studies on long-term OC accumulation in coastal sediments have limited reliable estimation of the capacity of seagrass meadows as a global OC sink. We evaluated the amount and accumulation rate of OC in sediment of seagrass meadows and adjacent areas in East and Southeast Asia. In temperate sites, the average OC concentration in the top 30 cm of sediment was higher in seagrass meadows (780-1080 mmol g-1) than in sediments without seagrass cover (52-430 mmol g-1). The average OC in the top 30 cm of subtropical and tropical seagrass meadow sediments ranged from 140 to 440 mmol g-1. Carbon isotope mass balancing suggested that the contribution of seagrass-derived carbon to OC stored in sediments was often relatively minor (temperate: 10-40%; subtropical: 35-82%; tropical: 4-34%) and correlated to the habitat type, being particularly low in estuarine habitats. Stock of OC in the top meter of sediment of all the studied meadows ranged from 38 to 120 Mg ha-1. The sediment accumulation rates were estimated by radiocarbon dating of six selected cores (0.32-1.34 mm yr-1). The long-term OC accumulation rates calculated from the sediment accumulation rate and the top 30 cm average OC concentration for the seagrass meadows (24-101 kg ha-1 yr-1) were considerably lower than the OC accumulation rates previously reported for Mediterranean Posidonia oceanica meadows (580 kg ha-1 yr-1 on average). Current estimates for the global carbon sink capacity of seagrass meadows, which rely largely on Mediterranean studies, may be considerable overestimations.

  15. Reducing arsenic accumulation in rice grain through iron oxide amendment.

    PubMed

    Farrow, Eric M; Wang, Jianmin; Burken, Joel G; Shi, Honglan; Yan, Wengui; Yang, John; Hua, Bin; Deng, Baolin

    2015-08-01

    Effects of soil-arsenic (As), phosphorus and iron oxide on As accumulation in rice grain were investigated. Cultivars that have significantly different sensitivity to As, straighthead-resistant Zhe 733 and straighthead-susceptible Cocodrie, were used to represent different cultivar varieties. The grain accumulation of other elements of concern, selenium (Se), molybdenum (Mo), and cadmium (Cd) was also monitored. Results demonstrated that high soil-As not only resulted in high grain-As, but could also result in high grain-Se, and Zhe 733 had significantly less grain-As than Cocodrie did. However, soil-As did not impact grain-Mo and Cd. Among all elements monitored, iron oxide amendment significantly reduced grain-As for both cultivars, while the phosphate application only reduced grain-Se for Zhe 733. Results also indicated that cultivar type significantly impacted grain accumulation of all monitored trace elements. Therefore, applying iron oxide to As-contaminated land, in addition to choosing appropriate rice cultivar, can effectively reduce the grain accumulation of As. PMID:25910688

  16. Upstream Material Accumulation and Meandering on Present Day Gully Evolution

    NASA Astrophysics Data System (ADS)

    Pasquon, K.; Gargani, J.; Massé, M.; Conway, S. J.; Vincendon, M.; Séjourné, A.

    2016-09-01

    Here we show the present day evolution of a martian gully during the last 4 MY: (1) non-seasonal material accumulation in the alcove, (2) seasonal evolution of meanders, (3) extension of the channel, (4) significant modifications of the debris apron.

  17. Sequential biases in accumulating evidence

    PubMed Central

    Huggins, Richard; Dogo, Samson Henry

    2015-01-01

    Whilst it is common in clinical trials to use the results of tests at one phase to decide whether to continue to the next phase and to subsequently design the next phase, we show that this can lead to biased results in evidence synthesis. Two new kinds of bias associated with accumulating evidence, termed ‘sequential decision bias’ and ‘sequential design bias’, are identified. Both kinds of bias are the result of making decisions on the usefulness of a new study, or its design, based on the previous studies. Sequential decision bias is determined by the correlation between the value of the current estimated effect and the probability of conducting an additional study. Sequential design bias arises from using the estimated value instead of the clinically relevant value of an effect in sample size calculations. We considered both the fixed‐effect and the random‐effects models of meta‐analysis and demonstrated analytically and by simulations that in both settings the problems due to sequential biases are apparent. According to our simulations, the sequential biases increase with increased heterogeneity. Minimisation of sequential biases arises as a new and important research area necessary for successful evidence‐based approaches to the development of science. © 2015 The Authors. Research Synthesis Methods Published by John Wiley & Sons Ltd. PMID:26626562

  18. 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.

  19. 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

  20. Overexpression of Arabidopsis phytochelatin synthase in tobacco plants enhances Cd(2+) tolerance and accumulation but not translocation to the shoot.

    PubMed

    Pomponi, Mirella; Censi, Vincenzo; Di Girolamo, Valentina; De Paolis, Angelo; di Toppi, Luigi Sanità; Aromolo, Rita; Costantino, Paolo; Cardarelli, Maura

    2006-01-01

    Phytochelatins (PCs) are metal binding peptides involved in heavy metal detoxification. To assess whether enhanced phytochelatin synthesis would increase heavy metal tolerance and accumulation in plants, we overexpressed the Arabidopsis phytochelatin synthase gene (AtPCS1) in the non-accumulator plant Nicotiana tabacum. Wild-type plants and plants harbouring the Agrobacterium rhizogenes rolB oncogene were transformed with a 35S AtPCS1 construct. Root cultures from rolB plants could be easily established and we demonstrated here that they represent a reliable system to study heavy metal tolerance. Cd(2+) tolerance in cultured rolB roots was increased as a result of overexpression of AtPCS1, and further enhanced when reduced glutathione (GSH, the substrate of PCS1) was added to the culture medium. Accordingly, HPLC analysis showed that total PC production in PCS1-overexpressing rolB roots was higher than in rolB roots in the presence of GSH. Overexpression of AtPCS1 in whole seedlings led to a twofold increase in Cd(2+) accumulation in the roots and shoots of both rolB and wild-type seedlings. Similarly, a significant increase in Cd(2+) accumulation linked to a higher production of PCs in both roots and shoots was observed in adult plants. However, the percentage of Cd(2+) translocated to the shoots of seedlings and adult overexpressing plants was unaffected. We conclude that the increase in Cd(2+) tolerance and accumulation of PCS1 overexpressing plants is directly related to the availability of GSH, while overexpression of phytochelatin synthase does not enhance long distance root-to-shoot Cd(2+) transport. PMID:16133212

  1. Gender differences in methionine accumulation and metabolism in freshly isolated mouse hepatocytes: Potential roles in toxicity

    SciTech Connect

    Dever, Joseph T.; Elfarra, Adnan A.

    2009-05-01

    L-Methionine (Met) is hepatotoxic at high concentrations. Because Met toxicity in freshly isolated mouse hepatocytes is gender-dependent, the goal of this study was to assess the roles of Met accumulation and metabolism in the increased sensitivity of male hepatocytes to Met toxicity compared with female hepatocytes. Male hepatocytes incubated with Met (30 mM) at 37 {sup o}C exhibited higher levels of intracellular Met at 0.5, 1.0, and 1.5 h, respectively, compared to female hepatocytes. Conversely, female hepatocytes had higher levels of S-adenosyl-L-methionine compared to male hepatocytes. Female hepatocytes also exhibited higher L-methionine-L-sulfoxide levels relative to control hepatocytes, whereas the increases in L-methionine-D-sulfoxide (Met-D-O) levels were similar in hepatocytes of both genders. Addition of aminooxyacetic acid (AOAA), an inhibitor of Met transamination, significantly increased Met levels at 1.5 h and increased Met-D-O levels at 1.0 and 1.5 h only in Met-exposed male hepatocytes. No gender differences in cytosolic Met transamination activity by glutamine transaminase K were detected. However, female mouse liver cytosol exhibited higher methionine-DL-sulfoxide (MetO) reductase activity than male mouse liver cytosol at low (0.25 and 0.5 mM) MetO concentrations. Collectively, these results suggest that increased cellular Met accumulation, decreased Met transmethylation, and increased Met and MetO transamination in male mouse hepatocytes may be contributing to the higher sensitivity of the male mouse hepatocytes to Met toxicity in comparison with female mouse hepatocytes.

  2. [Submitting studies without significant results].

    PubMed

    Texier, Gaëtan; Meynard, Jean-Baptiste; Michel, Rémy; Migliani, René; Boutin, Jean-Paul

    2007-03-01

    When a study finds that no exposure factor or therapy is significantly related to a given effect, researchers legitimately wonder if the results should be submitted for publication and to what journal. Clinical trials that report significant associations have a higher probability of publication, a phenomenon known as selective publication. The principal reasons of this selective publication include author self-censorship, peer-reviewing, trials not intended for publication, interpretation of the p value, cost of journal subscriptions, and policies. Subsequent reviews and meta-analyses are biased by the unavailability of nonsignificant results. Suggestions for preventing this risk include university training, trial registries, an international standard randomised controlled trial number (ISRCTN), Cochrane collaboration, and the gray literature. Journals (including electronic journals) interested in studies with nonsignificant results are listed. New technologies are changing the relations between publishers, libraries, authors and readers. PMID:17287106

  3. 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

  4. Trehalose accumulation in Azospirillum brasilense improves drought tolerance and biomass in maize plants.

    PubMed

    Rodríguez-Salazar, Julieta; Suárez, Ramón; Caballero-Mellado, Jesús; Iturriaga, Gabriel

    2009-07-01

    Bacteria of the genus Azospirillum increase the grain yield of several grass crops. In this work the effect of inoculating maize plants with genetically engineered Azospirillum brasilense for trehalose biosynthesis was determined. Transformed bacteria with a plasmid harboring a trehalose biosynthesis gene-fusion from Saccharomyces cerevisiae were able to grow up to 0.5 M NaCl and to accumulate trehalose, whereas wild-type A. brasilense did not tolerate osmotic stress or accumulate significant levels of the disaccharide. Moreover, 85% of maize plants inoculated with transformed A. brasilense survived drought stress, in contrast with only 55% of plants inoculated with the wild-type strain. A 73% increase in biomass of maize plants inoculated with transformed A. brasilense compared with inoculation with the wild-type strain was found. In addition, there was a significant increase of leaf and root length in maize plants inoculated with transformed A. brasilense. Therefore, inoculation of maize plants with A. brasilense containing higher levels of trehalose confers drought tolerance and a significant increase in leaf and root biomass. This work opens the possibility that A. brasilense modified with a chimeric trehalose biosynthetic gene from yeast could increase the biomass, grain yield and stress tolerance in other relevant crops.

  5. 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...

  6. Annual accumulation over the Greenland ice sheet interpolated from historical and newly compiled observation data

    USGS Publications Warehouse

    Shen, Dayong; Liu, Yuling; Huang, Shengli

    2012-01-01

    The estimation of ice/snow accumulation is of great significance in quantifying the mass balance of ice sheets and variation in water resources. Improving the accuracy and reducing uncertainty has been a challenge for the estimation of annual accumulation over the Greenland ice sheet. In this study, we kriged and analyzed the spatial pattern of accumulation based on an observation data series including 315 points used in a recent research, plus 101 ice cores and snow pits and newly compiled 23 coastal weather station data. The estimated annual accumulation over the Greenland ice sheet is 31.2 g cm−2 yr−1, with a standard error of 0.9 g cm−2 yr−1. The main differences between the improved map developed in this study and the recently published accumulation maps are in the coastal areas, especially southeast and southwest regions. The analysis of accumulations versus elevation reveals the distribution patterns of accumulation over the Greenland ice sheet.

  7. Anthropological significance of phenylketonuria.

    PubMed

    Saugstad, L F

    1975-01-01

    The highest incidence rates of phenylketonuria (PKU) have been observed in Ireland and Scotlant. Parents heterozygous for PKU in Norway differ significantly from the general population in the Rhesus, Kell and PGM systems. The parents investigated showed an excess of Rh negative, Kell plus and PGM type 1 individuals, which makes them similar to the present populations in Ireland and Scotlant. It is postulated that the heterozygotes for PKU in Norway are descended from a completely assimilated sub-population of Celtic origin, who came or were brought here, 1ooo years ago. Bronze objects of Western European (Scottish, Irish) origin, found in Viking graves widely distributed in Norway, have been taken as evidence of Vikings returning with loot (including a number of Celts) from Western Viking settlements. The continuity of residence since the Viking age in most habitable parts of Norway, and what seems to be a nearly complete regional relationship between the sites where Viking graves contain western imported objects and the birthplaces of grandparents of PKUs identified in Norway, lend further support to the hypothesis that the heterozygotes for PKU in Norway are descended from a completely assimilated subpopulation. The remarkable resemblance between Iceland and Ireland, in respect of several genetic markers (including the Rhesus, PGM and Kell systems), is considered to be an expression of a similar proportion of people of Celtic origin in each of the two countries. Their identical, high incidence rates of PKU are regarded as further evidence of this. The significant decline in the incidence of PKU when one passes from Ireland, Scotland and Iceland, to Denmark and on to Norway and Sweden, is therefore explained as being related to a reduction in the proportion of inhabitants of Celtic extraction in the respective populations.

  8. The Higher Education Enterprise.

    ERIC Educational Resources Information Center

    Ottinger, Cecilia A.

    1991-01-01

    Higher education not only contributes to the development of the human resources and intellectual betterment of the nation but is also a major economic enterprise. This research brief reviews and highlights data on the size and growth of higher education and illustrates how higher education institutions are preparing the future labor force. It…

  9. Reflections on "Higher Education"

    ERIC Educational Resources Information Center

    Gilbert, Felix

    1974-01-01

    The elitist, professional, and philosophical elements of higher education are reflected upon with stress on the differences between higher education and higher learning, where education is concerned with giving wider groups a share in a broad image of man, and learning is concerned with increasing specialization. (JH)

  10. Mononuclear phagocyte accumulates a stearic acid derivative during differentiation into macrophages. Effects of stearic acid on macrophage differentiation and Mycobacterium tuberculosis control.

    PubMed

    Mosquera-Restrepo, Sergio Fabián; Caro, Ana Cecilia; Peláez-Jaramillo, Carlos Alberto; Rojas, Mauricio

    2016-05-01

    The fatty acid composition of monocytes changes substantially during differentiation into macrophages, increasing the proportion of saturated fatty acids. These changes prompted us to investigate whether fatty acid accumulation in the extracellular milieu could affect the differentiation of bystander mononuclear phagocytes. An esterified fatty acid derivative, stearate, was the only fatty acid that significantly increased in macrophage supernatants, and there were higher levels when cells differentiated in the presence of Mycobacterium tuberculosis H37Rv or purified protein derivative (PPD). Exogenous stearic acid enhanced the expression of HLA-DR and CD64; there was also accumulation of IL-12, TNF-α, IL-6, MIP-1 α and β and a reduction in MCP-1 and the bacterial load. These results suggested that during differentiation, a derivative of stearic acid, which promotes the process as well as the effector mechanisms of phagocytes against the mycobacterium, accumulates in the cell supernatants.

  11. High-Affinity Accumulation of a Maytansinoid in Cells via Weak Tubulin Interaction

    PubMed Central

    Goldmacher, Victor S.; Audette, Charlene A.; Guan, Yinghua; Sidhom, Eriene-Heidi; Shah, Jagesh V.; Whiteman, Kathleen R.; Kovtun, Yelena V.

    2015-01-01

    The microtubule-targeting maytansinoids accumulate in cells and induce mitotic arrest at 250- to 1000-fold lower concentrations than those required for their association with tubulin or microtubules. To identify the mechanisms of this intracellular accumulation and exceptional cytotoxicity of maytansinoids we studied interaction of a highly cytotoxic maytansinoid, S-methyl DM1 and several other maytansinoids with cells. S-methyl DM1 accumulated inside the cells with a markedly higher apparent affinity than to tubulin or microtubules. The apparent affinities of maytansinoids correlated with their cytotoxicities. The number of intracellular binding sites for S-methyl DM1 in MCF7 cells was comparable to the number of tubulin molecules per cell (~ 4–6 × 107 copies). Efflux of 3 [H]-S-methyl DM1 from cells was enhanced in the presence of an excess of non-labeled S-methyl DM1, indicating that re-binding of 3 [H]-S-methyl DM1 to intracellular binding sites contributed to its intracellular retention. Liposomes loaded with non-polymerized tubulin recapitulated the apparent high-affinity association of S-methyl DM1 to cells. We propose a model for the intracellular accumulation of maytansinoids in which molecules of the compounds diffuse into a cell and associate with tubulin. Affinities of maytansinoids for individual tubulin molecules are weak, but the high intracellular concentration of tubulin favors, after dissociation of a compound-tubulin complex, their re-binding to a tubulin molecule, or to a tip of a microtubule in the same cell, over their efflux. As a result, a significant fraction of microtubule tips is occupied with a maytansinoid when added to cells at sub-nanomolar concentrations, inducing mitotic arrest and cell death. PMID:25671541

  12. An Oleaginous Bacterium That Intrinsically Accumulates Long-Chain Free Fatty Acids in its Cytoplasm

    PubMed Central

    Katayama, Taiki; Kanno, Manabu; Morita, Naoki; Hori, Tomoyuki; Narihiro, Takashi; Mitani, Yasuo

    2014-01-01

    Medium- and long-chain fatty acids are present in organisms in esterified forms that serve as cell membrane constituents and storage compounds. A large number of organisms are known to accumulate lipophilic materials as a source of energy and carbon. We found a bacterium, designated GK12, that intrinsically accumulates free fatty acids (FFAs) as intracellular droplets without exhibiting cytotoxicity. GK12 is an obligatory anaerobic, mesophilic lactic acid bacterium that was isolated from a methanogenic reactor. Phylogenetic analysis based on 16S rRNA gene sequences showed that GK12 is affiliated with the family Erysipelotrichaceae in the phylum Firmicutes but is distantly related to type species in this family (less than 92% similarity in 16S rRNA gene sequence). Saturated fatty acids with carbon chain lengths of 14, 16, 18, and 20 were produced from glucose under stress conditions, including higher-than-optimum temperatures and the presence of organic solvents that affect cell membrane integrity. FFAs were produced at levels corresponding to up to 25% (wt/wt) of the dry cell mass. Our data suggest that FFA accumulation is a result of an imbalance between excess membrane fatty acid biosynthesis due to homeoviscous adaptation and limited β-oxidation activity due to anaerobic growth involving lactic acid fermentation. FFA droplets were not further utilized as an energy and carbon source, even under conditions of starvation. A naturally occurring bacterium that accumulates significant amounts of long-chain FFAs with noncytotoxicity would provide useful strategies for microbial biodiesel production. PMID:24296497

  13. Comparison of Current and Historical Rates of Ecosystem Carbon Accumulation in a Northern Alberta Peatland

    NASA Astrophysics Data System (ADS)

    Syed, K. H.; Flanagan, L. B.; Carlson, P. J.; Glenn, A. J.; Ponton, S.

    2005-12-01

    As part of Fluxnet-Canada, we have been investigating the environmental controls on net ecosystem carbon dioxide exchange using the eddy covariance technique in a moderately rich (treed) fen in northern Alberta, Canada. In addition, integrated CO2 fluxes were compared to carbon stock measurements and rates of peat accumulation. The total ecosystem carbon stock was 52,669 g C m-2 with the vast majority (52,129) accumulated in peat over a 2 meter depth. The basal age for the peat was 2210 ± 50 years before present. The above-ground carbon stock in the two tree species was 226 g C m-2. The oldest Picea mariana trees were aged at 135 years, and they showed a rapid increase in basal area increment starting about 65 years ago that peaked at rates of 2 cm2 yr-1 about 40 years ago. The Larix laricina trees became established approximately 45 years ago and currently have a basal area increment of 3 to 4 cm2 yr-1, much higher than the current rates (0.5 cm2 yr-1) observed for Picea mariana. The rates of peat accumulation were determined on 210Pb-dated cores. Over the last 70 years the peat gained an average of 113 ± 12 g C m-2 yr-1. This was similar to net ecosystem production measured by eddy covariance (95 and 210 g C m-2 yr-1) over the last two years. Variation in annual net ecosystem production was associated with shifts in weather and growing season length. Current and recent historical rates of carbon accumulation were quite consistent despite significant variation in tree species growth and successional changes in this peatland over the last 70 years.

  14. Differential Effects of Conservational Management on SOC Accumulation in the Grasslands of China.

    PubMed

    Zhang, Ping; Tang, Jie; Sun, Wenjuan; Yu, Yongqiang; Zhang, Wen

    2015-01-01

    Conservational management practices in grasslands have been considered one of the efficient options to enhance the soil organic carbon (SOC) accumulation. However, the SOC changes after the conservational management practices vary significantly under different grassland vegetation types and the environmental conditions. At present, it is not clear how the SOC accumulation changes along the soil profile if conservational management practice was adopted. In this study, we collected 663 paired observational data of SOC changes with and without conservational management practices in grasslands of China from 176 published literatures that has both the surface (0‒20 cm) and subsurface (to 40 cm depth) SOC measurements. The differences of SOC density (SOCD) between pre‒management and post‒management in the vertical soil layers were analyzed in order to establish a quantitative relationship of the SOC changes between the subsurface and the surface. The results revealed that in all grasslands, conservational management practices benefits the SOC accumulation by enhancing 0.43‒1.14 Mg C ha-1 yr-1. But the SOC increment weakened downwards along the soil profile. While the surface SOC was enhanced by 17% after conservational management, the subsurface SOC was enhanced by only 7%. The SOC accumulation was closely correlated with restoration duration, pre-management SOCD and the environmental factors and differed greatly among different grasslands and the practices adopted. The alpine and mountain grassland showed a higher annual SOC increment than the temperate grassland with the annual rate of 1.62 and 0.72 Mg C ha-1 yr-1, respectively. The SOC increment caused by the artificial plantation and the grazing exclusion conservational management was more than 2-fold that of the cropland abandonment and the extensive utilization. With the quantitative relationship of the SOC changes between soil layers, we provide a methodological option to estimate SOC changes to layers

  15. Differential Effects of Conservational Management on SOC Accumulation in the Grasslands of China.

    PubMed

    Zhang, Ping; Tang, Jie; Sun, Wenjuan; Yu, Yongqiang; Zhang, Wen

    2015-01-01

    Conservational management practices in grasslands have been considered one of the efficient options to enhance the soil organic carbon (SOC) accumulation. However, the SOC changes after the conservational management practices vary significantly under different grassland vegetation types and the environmental conditions. At present, it is not clear how the SOC accumulation changes along the soil profile if conservational management practice was adopted. In this study, we collected 663 paired observational data of SOC changes with and without conservational management practices in grasslands of China from 176 published literatures that has both the surface (0‒20 cm) and subsurface (to 40 cm depth) SOC measurements. The differences of SOC density (SOCD) between pre‒management and post‒management in the vertical soil layers were analyzed in order to establish a quantitative relationship of the SOC changes between the subsurface and the surface. The results revealed that in all grasslands, conservational management practices benefits the SOC accumulation by enhancing 0.43‒1.14 Mg C ha-1 yr-1. But the SOC increment weakened downwards along the soil profile. While the surface SOC was enhanced by 17% after conservational management, the subsurface SOC was enhanced by only 7%. The SOC accumulation was closely correlated with restoration duration, pre-management SOCD and the environmental factors and differed greatly among different grasslands and the practices adopted. The alpine and mountain grassland showed a higher annual SOC increment than the temperate grassland with the annual rate of 1.62 and 0.72 Mg C ha-1 yr-1, respectively. The SOC increment caused by the artificial plantation and the grazing exclusion conservational management was more than 2-fold that of the cropland abandonment and the extensive utilization. With the quantitative relationship of the SOC changes between soil layers, we provide a methodological option to estimate SOC changes to layers

  16. Differential Effects of Conservational Management on SOC Accumulation in the Grasslands of China

    PubMed Central

    Zhang, Ping; Tang, Jie; Sun, Wenjuan; Yu, Yongqiang; Zhang, Wen

    2015-01-01

    Conservational management practices in grasslands have been considered one of the efficient options to enhance the soil organic carbon (SOC) accumulation. However, the SOC changes after the conservational management practices vary significantly under different grassland vegetation types and the environmental conditions. At present, it is not clear how the SOC accumulation changes along the soil profile if conservational management practice was adopted. In this study, we collected 663 paired observational data of SOC changes with and without conservational management practices in grasslands of China from 176 published literatures that has both the surface (0‒20 cm) and subsurface (to 40 cm depth) SOC measurements. The differences of SOC density (SOCD) between pre‒management and post‒management in the vertical soil layers were analyzed in order to establish a quantitative relationship of the SOC changes between the subsurface and the surface. The results revealed that in all grasslands, conservational management practices benefits the SOC accumulation by enhancing 0.43‒1.14 Mg C ha–1 yr–1. But the SOC increment weakened downwards along the soil profile. While the surface SOC was enhanced by 17% after conservational management, the subsurface SOC was enhanced by only 7%. The SOC accumulation was closely correlated with restoration duration, pre-management SOCD and the environmental factors and differed greatly among different grasslands and the practices adopted. The alpine and mountain grassland showed a higher annual SOC increment than the temperate grassland with the annual rate of 1.62 and 0.72 Mg C ha-1 yr-1, respectively. The SOC increment caused by the artificial plantation and the grazing exclusion conservational management was more than 2-fold that of the cropland abandonment and the extensive utilization. With the quantitative relationship of the SOC changes between soil layers, we provide a methodological option to estimate SOC changes to layers

  17. 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

  18. Himalayan Strain Accumulation 100 ka Timescales

    NASA Astrophysics Data System (ADS)

    Cannon, J. M.; Murphy, M. A.; Liu, Y.

    2015-12-01

    Crustal scale fault systems and tectonostratigraphic units in the Himalaya can be traced for 2500 km along strike. However regional studies have shown that there is variability in the location and rate of strain accumulation which appears to be driven by Main Himalayan Thrust (MHT) geometry and convergence obliquity. GPS illuminates the modern interseismic strain rate and the historical record of great earthquakes elucidates variations in strain accumulation over 103 years. To connect these patterns with the 106 year structural and thermochronometric geologic record we examine normalized river channel steepness (ksn), a proxy for rock uplift rate, which develops over 104 - 105 years. Here we present a ksn map of the Himalaya and compare it with bedrock geology, precipitation, the historic earthquake record, GPS, seismicity, and seismotectonic models. Our map shows significant along strike changes in the magnitude of channel steepness, the areal extent of swaths of high ksn channels, and their location with respect to the range front. Differences include the juxtaposition of two narrow (30 - 40 km) range parallel belts of high ksn in west Nepal and Bhutan coincident with MHT duplexes and belts of microseismcity, with a single broad (70 km) swath of high ksn and microseismicity in central and eastern Nepal. Separating west and central Nepal a band of low ksn crosses the range coincident with the West Nepal Fault (WNF) and the lowest rate of microseismicity in Nepal. To the west the orogen is obliquely convergent and has less high ksn channels, while the orthogonally convergent region to the east contains the highest concentration of oversteepened channels in the Himalaya supporting the idea that the WNF is a strain partitioning boundary. The syntaxes are characterized by locally high channel steepness surrounded by low to moderate ksn channels consistent with the hypothesis that rapid exhumation within the syntaxes is sustained by an influx of lower crust.

  19. 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

  20. 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.

  1. Accumulation and tolerance of lead in two contrasting ecotypes of Dianthus carthusianorum.

    PubMed

    Wójcik, Małgorzata; Tukiendorf, Anna

    2014-04-01

    Dianthus carthusianorum is one of the dominant plant species colonising the Zn-Pb waste deposits in Bolesław, Southern Poland. It differs in terms of morphology and genetics from ecotypes inhabiting non-metal-polluted areas. The response of waste-heap (metallicolous, M) and reference (nonmetallicolous, NM) ecotypes of D. carthusianorum to Pb in hydroponics was investigated and compared in this study. The plants of the M ecotype were more tolerant to Pb than these of the NM ecotype in spite of accumulation of higher concentrations of Pb. In both ecotypes, about 70-78% of Pb was retained in roots. In non Pb-treated plants, a higher glutathione (GSH) level was found in the M ecotype. After the Pb exposure, the GSH level decreased and was similar in both ecotypes. Lead treatment induced synthesis of phytochelatins (PCs) only in the plant roots, with significantly higher concentrations thereof detected in the NM ecotype. Malate and citrate concentrations were higher in the M ecotype; however, they did not change significantly upon any Pb treatment in either ecotype. The results indicated that neither PCs nor organic acids were responsible for the enhanced Pb tolerance of the waste-heap plants.

  2. 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

  3. 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.

  4. The Hesburgh Papers: Higher Values in Higher Education.

    ERIC Educational Resources Information Center

    Hesburgh, Theodore M.

    In this book the president of Notre Dame University responds to the critics who see the teaching of religion and values as a hindrance to institutions of higher learning, suggesting that no university is truly a university unless it is universal and moves every scholar to look to the total universe. The significance of values in education is…

  5. Citrate Accumulation-Related Gene Expression and/or Enzyme Activity Analysis Combined With Metabolomics Provide a Novel Insight for an Orange Mutant

    PubMed Central

    Guo, Ling-Xia; Shi, Cai-Yun; Liu, Xiao; Ning, Dong-Yuan; Jing, Long-Fei; Yang, Huan; Liu, Yong-Zhong

    2016-01-01

    ‘Hong Anliu’ (HAL, Citrus sinensis cv. Hong Anliu) is a bud mutant of ‘Anliu’ (AL), characterized by a comprehensive metabolite alteration, such as lower accumulation of citrate, high accumulation of lycopene and soluble sugars in fruit juice sacs. Due to carboxylic acid metabolism connects other metabolite biosynthesis and/or catabolism networks, we therefore focused analyzing citrate accumulation-related gene expression profiles and/or enzyme activities, along with metabolic fingerprinting between ‘HAL’ and ‘AL’. Compared with ‘AL’, the transcript levels of citrate biosynthesis- and utilization-related genes and/or the activities of their respective enzymes such as citrate synthase, cytosol aconitase and ATP-citrate lyase were significantly higher in ‘HAL’. Nevertheless, the mitochondrial aconitase activity, the gene transcript levels of proton pumps, including vacuolar H+-ATPase, vacuolar H+-PPase, and the juice sac-predominant p-type proton pump gene (CsPH8) were significantly lower in ‘HAL’. These results implied that ‘HAL’ has higher abilities for citrate biosynthesis and utilization, but lower ability for the citrate uptake into vacuole compared with ‘AL’. Combined with the metabolites-analyzing results, a model was then established and suggested that the reduction in proton pump activity is the key factor for the low citrate accumulation and the comprehensive metabolite alterations as well in ‘HAL’. PMID:27385485

  6. Enhanced production of nitric oxide, reactive oxygen species, and pro-inflammatory cytokines in very long chain saturated fatty acid-accumulated macrophages

    PubMed Central

    Yanagisawa, Naotake; Shimada, Kazunori; Miyazaki, Tetsuro; Kume, Atsumi; Kitamura, Yohei; Sumiyoshi, Katsuhiko; Kiyanagi, Takashi; Iesaki, Takafumi; Inoue, Nao; Daida, Hiroyuki

    2008-01-01

    Background Deterioration of peroxisomal β-oxidation activity causes an accumulation of very long chain saturated fatty acids (VLCSFA) in various organs. We have recently reported that the levels of VLCSFA in the plasma and/or membranes of blood cells were significantly higher in patients with metabolic syndrome and in patients with coronary artery disease than the controls. The aim of the present study is to investigate the effect of VLCSFA accumulation on inflammatory and oxidative responses in VLCSFA-accumulated macrophages derived from X-linked adrenoleukodystrophy (X-ALD) protein (ALDP)-deficient mice. Results Elevated levels of VLCSFA were confirmed in macrophages from ALDP-deficient mice. The levels of nitric oxide (NO) production stimulated by lipopolysaccharide (LPS) and interferon-γ (IFN-γ), intracellular reactive oxygen species (ROS), and pro-inflammatory cytokines, including tumor necrosis factor-α (TNF-α), interluekin-6 (IL-6), and interleukin-12p70 (IL-12p70), were significantly higher in macrophages from ALDP-deficient mice than in those from wild-type mice. The inducible NO synthase (iNOS) mRNA expression also showed an increase in macrophages from ALDP-deficient mice. Conclusion These results suggested that VLCSFA accumulation in macrophages may contribute to the pathogenesis of inflammatory diseases through the enhancement of inflammatory and oxidative responses. PMID:19038055

  7. A review on soil carbon accumulation due to the management change of major Brazilian agricultural activities.

    PubMed

    La Scala jr, N; De Figueiredo, E B; Panosso, A R

    2012-08-01

    Agricultural areas deal with enormous CO2 intake fluxes offering an opportunity for greenhouse effect mitigation. In this work we studied the potential of soil carbon sequestration due to the management conversion in major agricultural activities in Brazil. Data from several studies indicate that in soybean/maize, and related rotation systems, a significant soil carbon sequestration was observed over the year of conversion from conventional to no-till practices, with a mean rate of 0.41 Mg C ha(-1) year(-1). The same effect was observed in sugarcane fields, but with a much higher accumulation of carbon in soil stocks, when sugarcane fields are converted from burned to mechanised based harvest, where large amounts of sugarcane residues remain on the soil surface (1.8 Mg C ha(-1) year(-1)). The higher sequestration potential of sugarcane crops, when compared to the others, has a direct relation to the primary production of this crop. Nevertheless, much of this mitigation potential of soil carbon accumulation in sugarcane fields is lost once areas are reformed, or intensive tillage is applied. Pasture lands have shown soil carbon depletion once natural areas are converted to livestock use, while integration of those areas with agriculture use has shown an improvement in soil carbon stocks. Those works have shown that the main crop systems of Brazil have a huge mitigation potential, especially in soil carbon form, being an opportunity for future mitigation strategies.

  8. Positive effects of duckweed polycultures on starch and protein accumulation.

    PubMed

    Li, Yang; Zhang, Fantao; Daroch, Maurycy; Tang, Jie

    2016-10-01

    The effect of duckweed species composition (Lemna aequinoctialis 5505, Landoltia punctata 5506 and Spirodela polyrhiza 5507) in polyculture and monoculture on biomass and starch/protein content were investigated at different levels of temperature, light intensity, nitrogen and phosphorus concentrations. The three growth parameters significantly affect duckweed biomass accumulation. Different combinations of duckweed species greatly varied in starch/protein content. Although all the polycultures showed a median relative growth rate and the majority of the polycultures showed a median and starch/protein content as compared with their respective monocultures, some of the polycultures were found to promote the accumulation of starch/protein at different growth conditions. These findings indicated that proper combination of duckweed species could facilitate desirable biomass accumulation and improve biomass quality. The present study provides useful references for future large-scale duckweed cultivation. PMID:27515418

  9. Positive effects of duckweed polycultures on starch and protein accumulation.

    PubMed

    Li, Yang; Zhang, Fantao; Daroch, Maurycy; Tang, Jie

    2016-10-01

    The effect of duckweed species composition (Lemna aequinoctialis 5505, Landoltia punctata 5506 and Spirodela polyrhiza 5507) in polyculture and monoculture on biomass and starch/protein content were investigated at different levels of temperature, light intensity, nitrogen and phosphorus concentrations. The three growth parameters significantly affect duckweed biomass accumulation. Different combinations of duckweed species greatly varied in starch/protein content. Although all the polycultures showed a median relative growth rate and the majority of the polycultures showed a median and starch/protein content as compared with their respective monocultures, some of the polycultures were found to promote the accumulation of starch/protein at different growth conditions. These findings indicated that proper combination of duckweed species could facilitate desirable biomass accumulation and improve biomass quality. The present study provides useful references for future large-scale duckweed cultivation.

  10. Positive effects of duckweed polycultures on starch and protein accumulation

    PubMed Central

    Li, Yang; Zhang, Fantao; Daroch, Maurycy; Tang, Jie

    2016-01-01

    The effect of duckweed species composition (Lemna aequinoctialis 5505, Landoltia punctata 5506 and Spirodela polyrhiza 5507) in polyculture and monoculture on biomass and starch/protein content were investigated at different levels of temperature, light intensity, nitrogen and phosphorus concentrations. The three growth parameters significantly affect duckweed biomass accumulation. Different combinations of duckweed species greatly varied in starch/protein content. Although all the polycultures showed a median relative growth rate and the majority of the polycultures showed a median and starch/protein content as compared with their respective monocultures, some of the polycultures were found to promote the accumulation of starch/protein at different growth conditions. These findings indicated that proper combination of duckweed species could facilitate desirable biomass accumulation and improve biomass quality. The present study provides useful references for future large-scale duckweed cultivation. PMID:27515418

  11. 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).

  12. Radar detection of surface oil accumulations

    NASA Technical Reports Server (NTRS)

    Estes, J. E.; Oneill, P.; Wilson, M.

    1980-01-01

    The United States Coast Guard is developing AIREYE, an all weather, day/night airborne surveillance system, for installation aboard future medium range surveillance aircraft. As part of this program, a series of controlled tests were conducted off southern California to evaluate the oil slick detection capabilities of two Motorola developed, side looking radars. The systems, a real aperture AN/APS-94D and a synthetic aperture coherent on receive (COR) were flown over the Santa Barbara Channel on May 19, 1976. Targets imaged during the coincident overflights included natural oil seepage, simulated oil spills, oil production platforms, piers, mooring buoys, commercial boats and barges at other targets. Based on an analysis of imagery from the coincident radar runs, COR provides better detection of natural and man made oil slicks, whereas the AN/APS-94D consistently exhibited higher surface target detection results. This and other tests have shown that active microwave systems have considerable potential for aiding in the detection and analysis of surface oil accumulations.

  13. Damage accumulation in neon implanted silicon

    SciTech Connect

    Oliviero, E.; Peripolli, S.; Amaral, L.; Fichtner, P. F. P.; Beaufort, M. F.; Barbot, J. F.; Donnelly, S. E.

    2006-08-15

    Damage accumulation in neon-implanted silicon with fluences ranging from 5x10{sup 14} to 5x10{sup 16} Ne cm{sup -2} has been studied in detail. As-implanted and annealed samples were investigated by Rutherford backscattering spectrometry under channeling conditions and by transmission electron microscopy in order to quantify and characterize the lattice damage. Wavelength dispersive spectrometry was used to obtain the relative neon content stored in the matrix. Implantation at room temperature leads to the amorphization of the silicon while a high density of nanosized bubbles is observed all along the ion distribution, forming a uniform and continuous layer for implantation temperatures higher than 250 deg.C. Clusters of interstitial defects are also present in the deeper part of the layer corresponding to the end of range of ions. After annealing, the samples implanted at temperatures below 250 deg.C present a polycrystalline structure with blisters at the surface while in the other samples coarsening of bubbles occurs and nanocavities are formed together with extended defects identified as (311) defects. The results are discussed in comparison to the case of helium-implanted silicon and in the light of radiation-enhanced diffusion.

  14. Endogenous macrophage migration inhibitory factor reduces the accumulation and toxicity of misfolded SOD1 in a mouse model of ALS.

    PubMed

    Leyton-Jaimes, Marcel F; Benaim, Clara; Abu-Hamad, Salah; Kahn, Joy; Guetta, Amos; Bucala, Richard; Israelson, Adrian

    2016-09-01

    Mutations in superoxide dismutase (SOD1) cause amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disease characterized by the loss of upper and lower motor neurons in the brain and spinal cord. It has been suggested that the toxicity of mutant SOD1 results from its misfolding and accumulation on the cytoplasmic faces of intracellular organelles, including the mitochondria and endoplasmic reticulum (ER) of ALS-affected tissues. Recently, macrophage migration inhibitory factor (MIF) was shown to directly inhibit the accumulation of misfolded SOD1 and its binding to intracellular membranes, but the role of endogenous MIF in modulating SOD1 misfolding in vivo remains unknown. To elucidate this role, we bred MIF-deficient mice with SOD1(G85R) mice, which express a dismutase-inactive mutant of SOD1 and are considered a model of familial ALS. We found that the accumulation of misfolded SOD1, its association with mitochondrial and ER membranes, and the levels of sedimentable insoluble SOD1 aggregates were significantly higher in the spinal cords of SOD1(G85R)-MIF(-/-) mice than in their SOD1(G85R)-MIF(+/+) littermates. Moreover, increasing MIF expression in neuronal cultures inhibited the accumulation of misfolded SOD1 and rescued from mutant SOD1-induced cell death. In contrast, the complete elimination of endogenous MIF accelerated disease onset and late disease progression and shortened the lifespan of the SOD1(G85R) mutant mice. These findings indicate that MIF plays a significant role in the folding and misfolding of SOD1 in vivo, and they have implications for the potential therapeutic role of up-regulating MIF within the nervous system to modulate the selective accumulation of misfolded SOD1. PMID:27551074

  15. [Distribution and accumulation characteristics of nutrients in solar greenhouse soil in Ji'nan, Shandong Province of East China].

    PubMed

    Cao, Qi-Wei; Zhang, Wei-Hua; Li, Li-Bin; Sun, Yu-Liang; Sun, Xiao-Lei; Ai, Xi-Zhen

    2012-01-01

    Taking the solar greenhouses with different cultivating years and vegetables in Ji'nan as test objects, this paper studied the amounts and frequency distribution of soil nutrients and the relationships between cultivating years and soil nutrients accumulation characteristics, and analyzed the factors causing soil salinization and acidification by fitting soil nutrients contents with cultivating years and vegetables. In the greenhouses, the contents of soil alkali-hydrolysable nitrogen, available phosphorus, available potassium, organic matter, and electrical conductivity were significantly higher than those in the open field, with an increment of 135.3%, 475.2%, 290.1%, 97.7%, and 188.7%, respectively, but the soil pH value was 0.31 lower than that of open field. The frequency distribution of soil nutrients presented a normal curve. Differences were observed in the soil nutrients contents in the greenhouses with different cultivating vegetables. The soil alkali-hydrolysable nitrogen content and electrical conductivity were in the order of tomato > cucumber > sweet pepper, soil organic matter content and pH value were cucumber > sweet pepper > tomato, soil available phosphorus content was cucumber > tomato > sweet pepper, and soil available potassium content was tomato > cucumber > sweet pepper. There was a mild tendency of soil acidification in soil alkali-hydrolysable nitrogen and available potassium. The decrease of soil pH was closely related to the accumulation of alkali-hydrolysable nitrogen. The soil nutrients accumulation in the greenhouses had the similar patterns, i. e. , rapid accumulation in the first two cultivating years, slowed down in the third and fourth year, and kept stable later, demonstrating a dynamic balance on the whole. All the nutrients contents were positively accumulated, while soil pH presented negatively. In the greenhouses with different cultivating vegetables, there was a significant correlation between soil nutrients and cultivating

  16. Phytochelatin synthase of Thlaspi caerulescens enhanced tolerance and accumulation of heavy metals when expressed in yeast and tobacco.

    PubMed

    Liu, Ge-Yu; Zhang, Yu-Xiu; Chai, Tuan-Yao

    2011-06-01

    Phytochelatin synthase (PCS) is key enzyme for heavy metal detoxification and accumulation in plant. In this study, we isolated the PCS gene TcPCS1 from the hyperaccumulator Thlaspi caerulescens. Overexpression of TcPCS1 enhanced PC production in tobacco. Cd accumulation in the roots and shoots of TcPCS1 transgenic seedlings was increased compared to the wild type (WT), while Cd translocation from roots to shoots was not affected under Cd treatment. The root length of the TcPCS1 transgenic tobacco seedlings was significantly longer than that of the WT under Cd stress. These data indicate that TcPCS1 expression might increase Cd accumulation and tolerance in transgenic tobacco. In addition, the malondialdehyde content in TcPCS1 plants was below that of the wild type. However, the antioxidant enzyme activities of superoxide dismutase, peroxidase and catalase were found to be significantly higher than those of the WT when the transgenic plant was exposed to Cd stress. This suggests that the increase in PC production might enhance the Cd accumulation and thus increase the oxidative stress induced by the cadmium. The production of PCs could cause a transient decrease in the cytosolic glutathione (GSH) pool, and Cd and lower GSH concentration caused an increase in the oxidative response. We also determined TcPCS1 in Thlaspi caerulescens was regulated after exposure to various concentrations of CdCl(2) over different treatment times. Expression of TcPCS1 leading to increased Cd accumulation and enhanced metal tolerance, but the Cd contents were restrained by adding zinc in Saccharomyces cerevisiae transformants. PMID:21327392

  17. Fungi producing significant mycotoxins.

    PubMed

    2012-01-01

    Mycotoxins are secondary metabolites of microfungi that are known to cause sickness or death in humans or animals. Although many such toxic metabolites are known, it is generally agreed that only a few are significant in causing disease: aflatoxins, fumonisins, ochratoxin A, deoxynivalenol, zearalenone, and ergot alkaloids. These toxins are produced by just a few species from the common genera Aspergillus, Penicillium, Fusarium, and Claviceps. All Aspergillus and Penicillium species either are commensals, growing in crops without obvious signs of pathogenicity, or invade crops after harvest and produce toxins during drying and storage. In contrast, the important Fusarium and Claviceps species infect crops before harvest. The most important Aspergillus species, occurring in warmer climates, are A. flavus and A. parasiticus, which produce aflatoxins in maize, groundnuts, tree nuts, and, less frequently, other commodities. The main ochratoxin A producers, A. ochraceus and A. carbonarius, commonly occur in grapes, dried vine fruits, wine, and coffee. Penicillium verrucosum also produces ochratoxin A but occurs only in cool temperate climates, where it infects small grains. F. verticillioides is ubiquitous in maize, with an endophytic nature, and produces fumonisins, which are generally more prevalent when crops are under drought stress or suffer excessive insect damage. It has recently been shown that Aspergillus niger also produces fumonisins, and several commodities may be affected. F. graminearum, which is the major producer of deoxynivalenol and zearalenone, is pathogenic on maize, wheat, and barley and produces these toxins whenever it infects these grains before harvest. Also included is a short section on Claviceps purpurea, which produces sclerotia among the seeds in grasses, including wheat, barley, and triticale. The main thrust of the chapter contains information on the identification of these fungi and their morphological characteristics, as well as factors

  18. 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.

  19. 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

  20. Accumulation of heavy metals by vegetables grown in mine wastes

    SciTech Connect

    Cobb, G.P.; Sands, K.; Waters, M.; Wixson, B.G.; Dorward-King, E.

    2000-03-01

    Lead, cadmium, arsenic, and zinc were quantified in mine wastes and in soils mixed with mine wastes. Metal concentrations were found to be heterogeneous in the wastes. Iceberg lettuce, Cherry Belle radishes, Roma bush beans, and Better Boy tomatoes were cultivated in mine wastes and in waste-amended soils. Lettuce and radishes had 100% survival in the 100% mine waste treatments compared to 0% and 25% survival for tomatoes and beans, respectively. Metal concentrations were determined in plant tissues to determine uptake and distribution of metals in the edible plant parts. Individual soil samples were collected beneath each plant to assess metal content in the immediate plant environment. This analysis verified heterogeneous metal content of the mine wastes. The four plant species effectively accumulated and translocated lead, cadmium, arsenic, and zinc. Tomato and bean plants contained the four metals mainly in the roots and little was translocated to the fruits. Radish roots accumulated less metals compared to the leaves, whereas lettuce roots and leaves accumulated similar concentrations of the four metals. Lettuce leaves and radish roots accumulated significantly more metals than bean and tomato fruits. This accumulation pattern suggests that consumption of lettuce leaves or radish roots from plants grown in mine wastes would pose greater risks to humans and wildlife than would consumption of beans or tomatoes grown in the same area. The potential risk may be mitigated somewhat in humans, as vegetables grown in mine wastes exhibited stunted growth and chlorosis.

  1. Patterns of sediment accumulation in the tidal marshes of Maine

    USGS Publications Warehouse

    Wood, M.E.; Kelley, J.T.; Belknap, D.F.

    1989-01-01

    One year's measurements of surficial sedimentation rates (1986-1987) for 26 Maine marsh sites were made over marker horizons of brick dust. Observed sediment accumulation rates, from 0 to 13 mm yr-1, were compared with marsh morphology, local relative sea-level rise rate, mean tidal range, and ice rafting activity. Marshes with four different morphologies (back-barrier, fluvial, bluff-toe, and transitional) showed distinctly different sediment accumulation rates. In general, back-barrier marshes had the highest accumulation rates and blufftoe marshes had the lowest rates, with intermediate values for transitional and fluvial marshes. No causal relationship between modern marsh sediment accumulation rate and relative sea-level rise rate (from tide gauge records) was observed. Marsh accretionary balance (sediment accumulation rate minus relative sea-level rise rate) did not correlate with mean tidal range for this meso- to macro-tidal area. Estimates of ice-rafted debris on marsh sites ranged from 0% to >100% of measured surficial sedimentation rates, indicating that ice transport of sediment may make a significant contribution to surficial sedimentation on Maine salt marshes. ?? 1989 Estuarine Research Federation.

  2. Surface-atmosphere decoupling limits accumulation at Summit, Greenland.

    PubMed

    Berkelhammer, Max; Noone, David C; Steen-Larsen, Hans Christian; Bailey, Adriana; Cox, Christopher J; O'Neill, Michael S; Schneider, David; Steffen, Konrad; White, James W C

    2016-04-01

    Despite rapid melting in the coastal regions of the Greenland Ice Sheet, a significant area (~40%) of the ice sheet rarely experiences surface melting. In these regions, the controls on annual accumulation are poorly constrained owing to surface conditions (for example, surface clouds, blowing snow, and surface inversions), which render moisture flux estimates from myriad approaches (that is, eddy covariance, remote sensing, and direct observations) highly uncertain. Accumulation is partially determined by the temperature dependence of saturation vapor pressure, which influences the maximum humidity of air parcels reaching the ice sheet interior. However, independent proxies for surface temperature and accumulation from ice cores show that the response of accumulation to temperature is variable and not generally consistent with a purely thermodynamic control. Using three years of stable water vapor isotope profiles from a high altitude site on the Greenland Ice Sheet, we show that as the boundary layer becomes increasingly stable, a decoupling between the ice sheet and atmosphere occurs. The limited interaction between the ice sheet surface and free tropospheric air reduces the capacity for surface condensation to achieve the rate set by the humidity of the air parcels reaching interior Greenland. The isolation of the surface also acts to recycle sublimated moisture by recondensing it onto fog particles, which returns the moisture back to the surface through gravitational settling. The observations highlight a unique mechanism by which ice sheet mass is conserved, which has implications for understanding both past and future changes in accumulation rate and the isotopic signal in ice cores from Greenland.

  3. Reclaiming Our Soul: Democracy and Higher Education.

    ERIC Educational Resources Information Center

    Chickering, Arthur W.

    2003-01-01

    Explores how, as higher education faces new financial realities together with escalating demands for more accountability, a call to reclaim the soul of higher education and with it, the soul of democracy, will require significant institutional and personal transformations. (EV)

  4. Earthworms accumulate alanine in response to drought.

    PubMed

    Holmstrup, Martin; Slotsbo, Stine; Henriksen, Per G; Bayley, Mark

    2016-09-01

    Earthworms have ecologically significant functions in tropical and temperate ecosystems and it is therefore important to understand how these animals survive during drought. In order to explore the physiological responses to dry conditions, we simulated a natural drought incident in a laboratory trial exposing worms in slowly drying soil for about one month, and then analyzed the whole-body contents of free amino acids (FAAs). We investigated three species forming estivation chambers when soils dry out (Aporrectodea tuberculata, Aporrectodea icterica and Aporrectodea longa) and one species that does not estivate during drought (Lumbricus rubellus). Worms subjected to drought conditions (< -2MPa) substantially increased the concentration of FAAs and in particular alanine that was significantly upregulated in all tested species. Alanine was the most important FAA reaching 250-650μmolg(-1) dry weight in dehydrated Aporrectodea species and 300μmolg(-1) dry weight in L. rubellus. Proline was only weakly upregulated in some species as were a few other FAAs. Species forming estivation chambers (Aporrectodea spp.) did not show a better ability to conserve body water than the non-estivating species (L. rubellus) at the same drought level. These results suggest that the accumulation of alanine is an important adaptive trait in drought tolerance of earthworms in general. PMID:27107492

  5. Distinctive denitrifying capabilities lead to differences in N2O production by denitrifying polyphosphate accumulating organisms and denitrifying glycogen accumulating organisms.

    PubMed

    Ribera-Guardia, Anna; Marques, Ricardo; Arangio, Corrado; Carvalheira, Monica; Oehmen, Adrian; Pijuan, Maite

    2016-11-01

    This study aims at investigating the denitrification kinetics in two separate enriched cultures of denitrifying polyphosphate accumulating organisms (dPAO) and denitrifying glycogen accumulating organisms (dGAO) and compare their N2O accumulation potential under different conditions. Two sequencing batch reactors were inoculated to develop dPAO and dGAO enriched microbial communities separately. Seven batch tests with different combinations of electron acceptors (nitrate, nitrite and/or nitrous oxide) were carried out with the enriched biomass from both reactors. Results indicate that in almost all batch tests, N2O accumulated for both cultures, however dPAOs showed a higher denitrification capacity compared to dGAOs due to their higher nitrogen oxides reduction rates. Additionally, the effect of the simultaneous presence of several electron acceptors in the reduction rates of the different nitrogen oxides was also assessed in dPAOs and dGAOs. PMID:27479801

  6. Disability Discrimination in Higher Education.

    ERIC Educational Resources Information Center

    Weber, Mark C.

    2000-01-01

    Reviews court cases in 1999 related to disability discrimination in higher education focusing on the Americans with Disabilities Act and section 504 of the Rehabilitation Act of 1973. The "Garrett" case regarding Eleventh Amendment immunity is the case most likely to be significant in the development of the law of disability discrimination. (SLD)

  7. Employment Discrimination in Higher Education.

    ERIC Educational Resources Information Center

    Hustoles, Thomas P.; Griffin, Oren R.

    2000-01-01

    Reviews court decisions related to employment discrimination in higher education. The most significant development was a series of cases affirming that Eleventh Amendment immunity from private money damage claims brought pursuant to various federal employment discrimination statutes applied to state colleges and universities. (SLD)

  8. Women in Higher Education, 1997.

    ERIC Educational Resources Information Center

    Wenniger, Mary Dee, Ed.

    1997-01-01

    The 12 issues of this newsletter focus on issues concerned with women students, faculty, and administrators in higher education. Each issue includes feature articles, news items, and profiles of significant people. The issues' main articles address: women in athletics; leadership development for women; the first year in academic administration;…

  9. Morphological Characteristics, Anatomical Structure, and Gene Expression: Novel Insights into Cytokinin Accumulation during Carrot Growth and Development

    PubMed Central

    Wang, Guang-Long; Sun, Sheng; Xing, Guo-Ming; Wu, Xue-Jun; Wang, Feng; Xiong, Ai-Sheng

    2015-01-01

    Cytokinins have been implicated in normal plant growth and development. These bioactive molecules are essential for cell production and expansion in higher plants. Carrot is an Apiaceae vegetable with great value and undergoes significant size changes over the process of plant growth. However, cytokinin accumulation and its potential roles in carrot growth have not been elucidated. To address this problem, carrot plants at five stages were collected, and morphological and anatomical characteristics and expression profiles of cytokinin-related genes were determined. During carrot growth and development, cytokinin levels were the highest at the second stage in the roots, whereas relatively stable levels were observed in the petioles and leaves. DcCYP735A2 showed high expression at stage 2 in the roots, which may contribute largely to the higher cytokinin level at this stage. However, expression of most metabolic genes did not follow a pattern similar to that of cytokinin accumulation, indicating that cytokinin biosynthesis was regulated through a complex network. Genes involved in cytokinin signal perception and transduction were also integrated to normal plant growth and development. The results from the present work suggested that cytokinins may regulate plant growth in a stage-dependent manner. Our work would shed novel insights into cytokinin accumulation and its potential roles during carrot growth. Further studies regarding carrot cytokinins may be achieved by modification of the genes involved in cytokinin biosynthesis, inactivation, and perception. PMID:26218147

  10. Morphological Characteristics, Anatomical Structure, and Gene Expression: Novel Insights into Cytokinin Accumulation during Carrot Growth and Development.

    PubMed

    Wang, Guang-Long; Sun, Sheng; Xing, Guo-Ming; Wu, Xue-Jun; Wang, Feng; Xiong, Ai-Sheng

    2015-01-01

    Cytokinins have been implicated in normal plant growth and development. These bioactive molecules are essential for cell production and expansion in higher plants. Carrot is an Apiaceae vegetable with great value and undergoes significant size changes over the process of plant growth. However, cytokinin accumulation and its potential roles in carrot growth have not been elucidated. To address this problem, carrot plants at five stages were collected, and morphological and anatomical characteristics and expression profiles of cytokinin-related genes were determined. During carrot growth and development, cytokinin levels were the highest at the second stage in the roots, whereas relatively stable levels were observed in the petioles and leaves. DcCYP735A2 showed high expression at stage 2 in the roots, which may contribute largely to the higher cytokinin level at this stage. However, expression of most metabolic genes did not follow a pattern similar to that of cytokinin accumulation, indicating that cytokinin biosynthesis was regulated through a complex network. Genes involved in cytokinin signal perception and transduction were also integrated to normal plant growth and development. The results from the present work suggested that cytokinins may regulate plant growth in a stage-dependent manner. Our work would shed novel insights into cytokinin accumulation and its potential roles during carrot growth. Further studies regarding carrot cytokinins may be achieved by modification of the genes involved in cytokinin biosynthesis, inactivation, and perception.

  11. 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.

  12. Enhanced accumulation of starch and total carbohydrates in alginate-immobilized Chlorella spp. induced by Azospirillum brasilense: II. Heterotrophic conditions.

    PubMed

    Choix, Francisco J; de-Bashan, Luz E; Bashan, Yoav

    2012-10-10

    The effect of the bacterium Azospirillum brasilense jointly immobilized with Chlorella vulgaris or C. sorokiniana in alginate beads on total carbohydrates and starch was studied under dark and heterotrophic conditions for 144 h in synthetic growth medium supplemented with either d-glucose or Na-acetate as carbon sources. In all treatments, enhanced total carbohydrates and starch content per culture and per cell was obtained after 24h; only jointly immobilized C. vulgaris growing on d-glucose significantly increased total carbohydrates and starch content after 96 h. Enhanced accumulation of carbohydrate and starch under jointly immobilized conditions was variable with time of sampling and substrate used. Similar results occurred when the microalgae was immobilized alone. In both microalgae growing on either carbon sources, the bacterium promoted accumulation of carbohydrates and starch; when the microalgae were immobilized alone, they used the carbon sources for cell multiplication. In jointly immobilized conditions with Chlorella spp., affinity to carbon source and volumetric productivity and yield were higher than when Chlorella spp. were immobilized alone; however, the growth rate was higher in microalgae immobilized alone. This study demonstrates that under heterotrophic conditions, A. brasilense promotes the accumulation of carbohydrates in two strains Chlorella spp. under certain time-substrate combinations, producing mainly starch. As such, this bacterium is a biological factor that can change the composition of compounds in microalgae in dark, heterotrophic conditions.

  13. 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

  14. Morphological Characteristics, Anatomical Structure, and Gene Expression: Novel Insights into Cytokinin Accumulation during Carrot Growth and Development.

    PubMed

    Wang, Guang-Long; Sun, Sheng; Xing, Guo-Ming; Wu, Xue-Jun; Wang, Feng; Xiong, Ai-Sheng

    2015-01-01

    Cytokinins have been implicated in normal plant growth and development. These bioactive molecules are essential for cell production and expansion in higher plants. Carrot is an Apiaceae vegetable with great value and undergoes significant size changes over the process of plant growth. However, cytokinin accumulation and its potential roles in carrot growth have not been elucidated. To address this problem, carrot plants at five stages were collected, and morphological and anatomical characteristics and expression profiles of cytokinin-related genes were determined. During carrot growth and development, cytokinin levels were the highest at the second stage in the roots, whereas relatively stable levels were observed in the petioles and leaves. DcCYP735A2 showed high expression at stage 2 in the roots, which may contribute largely to the higher cytokinin level at this stage. However, expression of most metabolic genes did not follow a pattern similar to that of cytokinin accumulation, indicating that cytokinin biosynthesis was regulated through a complex network. Genes involved in cytokinin signal perception and transduction were also integrated to normal plant growth and development. The results from the present work suggested that cytokinins may regulate plant growth in a stage-dependent manner. Our work would shed novel insights into cytokinin accumulation and its potential roles during carrot growth. Further studies regarding carrot cytokinins may be achieved by modification of the genes involved in cytokinin biosynthesis, inactivation, and perception. PMID:26218147

  15. Higher-Resolution Data-Dependent Selective External Ion Accumulation for Capillary LC-FTICR.

    SciTech Connect

    Belov, Mikhail E. ); Anderson, Gordon A. ); Smith, Richard D. )

    2002-07-15

    Data-dependent selective external ion ejection with improved resolution is demonstrated with a 3.5 tesla FTICR instrument employing DREAMS (Dynamic Range Enhancement Applied to Mass Spectrometry) technology. To correct for the fringing rf-field aberrations each rod of the selection quadrupole has been segmented into three sections, so that ion excitation and ejection was performed by applying auxiliary rf-only waveforms in the region of the middle segments. Two different modes of external ion trapping and ejection were studied with the mixtures of model peptides and a tryptic digest of bovine serum albumin. A mass resolution of about 100 has been attained for rf-only dipolar ejection in a quadrupole operating at a Mathieu parameter q of{approx} 0.45. LC-ESI-DREAMS-FTICR analysis of a 0.1 mg/mL solution of bovine serum albumin digest resulted in detection of 82 unique tryptic peptides with mass measurement errors lower than 5 ppm, providing 100% sequence coverage of the protein.

  16. Higher-Resolution Data-Dependent Selective External ION Accumulation for Capillary LC-FTICR

    SciTech Connect

    Belov, Mikhail E.; Anderson, Gordon A.; Smith, Richard D.

    2002-07-15

    Data-dependent selective external ion ejection with improved resolution is demonstrated with a 3.5 tesla FTICR instrument employing DREAMS (Dynamic Range Enhancement Applied to Mass Spectrometry) technology. To correct for the fringing rf-field aberrations each rod of the selection quadrupole has been segmented into three sections, so that ion excitation and ejection was performed by applying auxiliary rf-only waveforms in the region of the middle segments. Two different modes of external ion trapping and ejection were studied with the mixtures of model peptides and a tryptic digest of bovine serum albumin. A mass resolution of about 100 had been attained for rf-only dipolar ejection in a quadrupole operating at a Mathieu parameter q of ~0.45. LC-ESI-DREAMS-FTICR analysis of a 0.1 mg/mL solution of bovine serum albumin digest resulted in detection of 82 unique tryptic peptides with mass measurement errors lower than 5 ppm, providing 100 % sequence coverage of the protein.

  17. Molecular analysis of polyphosphate accumulation in bacteria.

    PubMed

    Kuroda, A; Ohtake, H

    2000-03-01

    The dynamic behavior of inorganic polyphosphate (polyP), its accumulation and disappearance, is the most striking aspect of polyP metabolism in bacteria. Imbalance between polyP synthesis and degradation results in fluctuations of polyP by 100- to 1000-fold. We here review recent results with respect to this polyP metabolism in bacteria. PolyP accumulation in response to amino acid starvation, accompanied by increased levels of stringent factors, has been observed in Escherichia coli. Inhibition by stringent factors of polyphosphatase interrupts the dynamic balance between the synthesis and degradation of polyP, accounting for polyP accumulation. Polyphosphate kinase is required for activation of intracellular protein degradation, which is required for adaptation at the onset of amino acid starvation. The adaptation to amino acid starvation is mediated by the network of stringent response and polyP metabolism. PolyP accumulation independent of stringent response has also been observed. Novobiocin, an inhibitor for DNA gyrase, stimulated accumulation of polyP but not that of stringent factors. However, a temperature-sensitive DNA gyrase mutant did not exhibit polyP accumulation at the non-permissive temperature. Antagonistic relationship of polyP to nucleic acid synthesis, explored by Harold, appears to be more complicated. We discuss relationship of Pi regulation to polyP accumulation in E. coli and Klebsiella aerogenes. A function of polyP as an in vivo phosphagen affecting polyP accumulation is also discussed.

  18. 46 CFR 58.30-25 - Accumulators.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... RELATED SYSTEMS Fluid Power and Control Systems § 58.30-25 Accumulators. (a) An accumulator is an unfired pressure vessel in which energy is stored under high pressure in the form of a gas or a gas and hydraulic... result in contamination of the hydraulic fluid and loss of gas through absorption. (c) Each...

  19. 46 CFR 58.30-25 - Accumulators.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... RELATED SYSTEMS Fluid Power and Control Systems § 58.30-25 Accumulators. (a) An accumulator is an unfired pressure vessel in which energy is stored under high pressure in the form of a gas or a gas and hydraulic... result in contamination of the hydraulic fluid and loss of gas through absorption. (c) Each...

  20. Chemical Form Matters: Differential Accumulation of Mercury Following Inorganic and Organic Mercury Exposures in Zebrafish Larvae

    SciTech Connect

    Korbas, Malgorzata; MacDonald, Tracy C.; Pickering, Ingrid J.; George, Graham N.; Krone, Patrick H.

    2013-04-08

    Mercury, one of the most toxic elements, exists in various chemical forms each with different toxicities and health implications. Some methylated mercury forms, one of which exists in fish and other seafood products, pose a potential threat, especially during embryonic and early postnatal development. Despite global concerns, little is known about the mechanisms underlying transport and toxicity of different mercury species. To investigate the impact of different mercury chemical forms on vertebrate development, we have successfully combined the zebrafish, a well-established developmental biology model system, with synchrotron-based X-ray fluorescence imaging. Our work revealed substantial differences in tissue-specific accumulation patterns of mercury in zebrafish larvae exposed to four different mercury formulations in water. Methylmercury species not only resulted in overall higher mercury burdens but also targeted different cells and tissues than their inorganic counterparts, thus revealing a significant role of speciation in cellular and molecular targeting and mercury sequestration. For methylmercury species, the highest mercury concentrations were in the eye lens epithelial cells, independent of the formulation ligand (chloride versus L-cysteine). For inorganic mercury species, in absence of L-cysteine, the olfactory epithelium and kidney accumulated the greatest amounts of mercury. However, with L-cysteine present in the treatment solution, mercuric bis-L-cysteineate species dominated the treatment, significantly decreasing uptake. Our results clearly demonstrate that the common differentiation between organic and inorganic mercury is not sufficient to determine the toxicity of various mercury species.

  1. In vitro percutaneous permeation and skin accumulation of finasteride using vesicular ethosomal carriers.

    PubMed

    Rao, Yuefeng; Zheng, Feiyue; Zhang, Xingguo; Gao, Jianqing; Liang, Wenquan

    2008-01-01

    In order to develop a novel transdermal drug delivery system that facilitates the skin permeation of finasteride encapsulated in novel lipid-based vesicular carriers (ethosomes)finasteride ethosomes were constructed and the morphological characteristics were studied by transmission electron microscopy. The particle size, zeta potential and the entrapment capacity of ethosome were also determined. In contrast to liposomes ethosomes were of more condensed vesicular structure and they were found to be oppositely charged. Ethosomes were found to be more efficient delivery carriers with high encapsulation capacities. In vitro percutaneous permeation experiments demonstrated that the permeation of finasteride through human cadaver skin was significantly increased when ethosomes were used. The finasteride transdermal fluxes from ethosomes containing formulation (1.34 +/- 0.11 microg/cm(2)/h) were 7.4, 3.2 and 2.6 times higher than that of finasteride from aqueous solution, conventional liposomes and hydroethanolic solution respectively (P < 0.01).Furthermore, ethosomes produced a significant (P < 0.01) finasteride accumulation in the skin, especially in deeper layers, for instance in dermis it reached to 18.2 +/- 1.8 microg/cm(2). In contrast, the accumulation of finasteride in the dermis was only 2.8 +/- 1.3 microg/cm(2) with liposome formulation. The study demonstrated that ethosomes are promising vesicular carriers for enhancing percutaneous absorption of finasteride.

  2. Effects of lead accumulation on the Azolla caroliniana-Anabaena association.

    PubMed

    Roberts, Anne E; Boylen, Charles W; Nierzwicki-Bauer, Sandra A

    2014-04-01

    The effect of lead accumulation on photopigment production, mineral nutrition, and Anabaena vegetative cell size and heterocyst formation in Azolla caroliniana was investigated. Plants were exposed to 0, 1, 5, 10, and 20 mg L(-1) lead acetate for ten days. Lead accumulation increased when plants were treated with higher lead concentrations. Results revealed a statistically significant decline in total chlorophyll, chlorophyll a, chlorophyll b, and carotenoids in 5, 10, and 20 mg Pb L(-1) treatment groups as compared to plants with 0 or 1 mg Pb L(-1) treatments. No statistically significant change in anthocyanin production was observed. Calcium, magnesium, and zinc concentrations in plants decreased in increasing treatment groups, whereas sodium and potassium concentrations increased. Nitrogen and carbon were also found to decrease in plant tissue. Anabaena vegetative cells decreased in size and heterocyst frequency declined rapidly in a Pb dose-dependent manner. These results indicate that, while A. caroliniana removes lead from aqueous solution, the heavy metal causes physiological and biochemical changes by impairing photosynthesis, changing mineral nutrition, and impeding the growth and formation of heterocysts of the symbiotic cyanobacteria that live within leaf cavities of the fronds.

  3. Effects of lead accumulation on the Azolla caroliniana-Anabaena association.

    PubMed

    Roberts, Anne E; Boylen, Charles W; Nierzwicki-Bauer, Sandra A

    2014-04-01

    The effect of lead accumulation on photopigment production, mineral nutrition, and Anabaena vegetative cell size and heterocyst formation in Azolla caroliniana was investigated. Plants were exposed to 0, 1, 5, 10, and 20 mg L(-1) lead acetate for ten days. Lead accumulation increased when plants were treated with higher lead concentrations. Results revealed a statistically significant decline in total chlorophyll, chlorophyll a, chlorophyll b, and carotenoids in 5, 10, and 20 mg Pb L(-1) treatment groups as compared to plants with 0 or 1 mg Pb L(-1) treatments. No statistically significant change in anthocyanin production was observed. Calcium, magnesium, and zinc concentrations in plants decreased in increasing treatment groups, whereas sodium and potassium concentrations increased. Nitrogen and carbon were also found to decrease in plant tissue. Anabaena vegetative cells decreased in size and heterocyst frequency declined rapidly in a Pb dose-dependent manner. These results indicate that, while A. caroliniana removes lead from aqueous solution, the heavy metal causes physiological and biochemical changes by impairing photosynthesis, changing mineral nutrition, and impeding the growth and formation of heterocysts of the symbiotic cyanobacteria that live within leaf cavities of the fronds. PMID:24509077

  4. Influence of iron and zinc status on cadmium accumulation in Bangladeshi women

    SciTech Connect

    Kippler, Maria; Ekstroem, Eva-Charlotte; Loennerdal, Bo; Goessler, Walter; Akesson, Agneta; El Arifeen, Shams; Persson, Lars-Ake; Vahter, Marie . E-mail: Marie.Vahter@ki.se

    2007-07-15

    Cadmium is a widespread environmental contaminant present in food. The absorption in the intestine increases in individuals with low iron stores, but the effect of zinc deficiency is not clear. The aim of the present study was to assess the influence of iron and zinc status on cadmium accumulation in pregnant Bangladeshi women. We measured cadmium in urine from 890 women using inductively coupled plasma mass spectrometry (ICPMS). Further, we also measured ferritin and zinc in plasma. The median cadmium concentration in urine was 0.59 {mu}g/L (adjusted to mean specific gravity of 1.012 g/mL). Analysis of covariance (ANCOVA) showed that urinary cadmium was associated with plasma ferritin and plasma zinc via a significant interaction between dichotomized plasma ferritin and plasma zinc. The analysis was adjusted for age and socioeconomic status. Women with low iron stores and adequate zinc status had significantly higher urinary cadmium compared to women with both adequate iron stores and zinc status. There was no difference in urinary cadmium between women with both low iron stores and zinc status compared to those with both adequate iron stores and zinc status. In conclusion, low iron stores were associated with increased cadmium accumulation, but only at adequate zinc status.

  5. Effects of lead on live performance due to its accumulation in tissue

    NASA Astrophysics Data System (ADS)

    Ozcelik, D.; Akyolcu, M. C.; Dursun, S.; Toplan, S.; Kahraman, R.; Alp, M.

    2003-05-01

    Lead as a heavy metal that found in nature and highly used in industry is one of the toxic elements for living structures. In present study investigation of effects of lead as a heavy metal on live-weight of chickens due to accumulation level in different tissues were aimed. For such a purpose one-day-old chickens were divided into two groups as experiment groups as experimental and control. Experimental group animals were fed by lead added (300 mg Pb/kg as lead acetate) after four weeks chickens live weights were measured and tissue samples (liver, kidney, muscle, bone) were taken for lead concentration measurements in atomic absorption spectrometer. At the end of evaluation of data it was observed that live mean weight of experimental group was significantly lower than that of control group animals (p < 0.001). On the other hand tissue lead concentrations of experimental group were found to be significantly higher than that of control group values. So it may be concluded that accumulation of lead as a heavy metal may lead to decreased rate of animal growth.

  6. Accumulation of cadmium in tissue and its effect on live performance

    NASA Astrophysics Data System (ADS)

    Akyolcu, M. C.; Ozcelik, D.; Dursun, S.; Toplan, S.; Kahraman, R.

    2003-05-01

    Heavy metal pollution has gained more importance for environment as a result of increased industrialization rate all over the world. In present study investigation of effects of cadmium on live-weight due to accumulation in different tissues that taken in food were aimed. For such a purpose after their birth for four weeks chickens were fed by Cd added fodder (25 mg Cd/kg as cadmium sulfate). At the end offour weeks feeding period the chickens were scaled and sacrificed. For tissue cadmium level measurements, liver, kidney, muscle and bone dissections were performed on both experimental and same age contrai group animals. The measurements were performed in atomic absorption spectrophotometer. At the end of evaluation of data it was observed that live mean weight of experimental group was significantly lower than that of control group animals (p < 0.001). On the other hand tissue cadmium concentrations of experimental group were found to be significantly higher than that of control group values. So accumulation of cadmium in tissue as a heavy metal may lead decreased rate of growth.

  7. Pathological Significance of Mitochondrial Glycation

    PubMed Central

    Pun, Pamela Boon Li; Murphy, Michael P.

    2012-01-01

    Glycation, the nonenzymatic glycosylation of biomolecules, is commonly observed in diabetes and ageing. Reactive dicarbonyl species such as methylglyoxal and glyoxal are thought to be major physiological precursors of glycation. Because these dicarbonyls tend to be formed intracellularly, the levels of advanced glycation end products on cellular proteins are higher than on extracellular ones. The formation of glycation adducts within cells can have severe functional consequences such as inhibition of protein activity and promotion of DNA mutations. Although several lines of evidence suggest that there are specific mitochondrial targets of glycation, and mitochondrial dysfunction itself has been implicated in disease and ageing, it is unclear if glycation of biomolecules specifically within mitochondria induces dysfunction and contributes to disease pathology. We discuss here the possibility that mitochondrial glycation contributes to disease, focussing on diabetes, ageing, cancer, and neurodegeneration, and highlight the current limitations in our understanding of the pathological significance of mitochondrial glycation. PMID:22778743

  8. Salinity Stress Is Beneficial to the Accumulation of Chlorogenic Acids in Honeysuckle (Lonicera japonica Thunb.)

    PubMed Central

    Yan, Kun; Cui, Mingxing; Zhao, Shijie; Chen, Xiaobing; Tang, Xiaoli

    2016-01-01

    Honeysuckle (Lonicera japonica Thunb.) is a traditional medicinal plant in China that is particularly rich in chlorogenic acids, which are phenolic compounds with various medicinal properties. This study aimed to examine the effects of salinity stress on accumulation of chlorogenic acids in honeysuckle, through hydroponic experiments and field trials, and to examine the mechanisms underlying the effects. NaCl stress stimulated the transcription of genes encoding key enzymes in the synthesis of chlorogenic acids in leaves; accordingly, the concentrations of chlorogenic acids in leaves were significantly increased under NaCl stress, as was antioxidant activity. Specifically, the total concentration of leaf chlorogenic acids was increased by 145.74 and 50.34% after 30 days of 150 and 300 mM NaCl stress, respectively. Similarly, the concentrations of chlorogenic acids were higher in the leaves of plants in saline, compared with non-saline, plots, with increases in total concentrations of chlorogenic acids of 56.05 and 105.29% in October 2014 and 2015, respectively. Despite leaf biomass reduction, absolute amounts of chlorogenic acids per plant and phenylalanine ammonia-lyase (PAL) activity were significantly increased by soil salinity, confirming that the accumulation of chlorogenic acids in leaves was a result of stimulation of their synthesis under salinity stress. Soil salinity also led to elevated chlorogenic acid concentrations in honeysuckle flower buds, with significant increases in total chlorogenic acids concentration of 22.42 and 25.14% in May 2014 and 2015, respectively. Consistent with biomass reduction, the absolute amounts of chlorogenic acid per plant declined in flower buds of plants exposed to elevated soil salinity, with no significant change in PAL activity. Thus, salinity-induced chlorogenic acid accumulation in flower buds depended on an amplification effect of growth reduction. In conclusion, salinity stress improved the medicinal quality of

  9. Dissolved organic matter reduces algal accumulation of methylmercury

    USGS Publications Warehouse

    Luengen, Allison C.; Fisher, Nicholas S.; Bergamaschi, Brian A.

    2012-01-01

    Dissolved organic matter (DOM) significantly decreased accumulation of methylmercury (MeHg) by the diatom Cyclotella meneghiniana in laboratory experiments. Live diatom cells accumulated two to four times more MeHg than dead cells, indicating that accumulation may be partially an energy-requiring process. Methylmercury enrichment in diatoms relative to ambient water was measured by a volume concentration factor (VCF). Without added DOM, the maximum VCF was 32 x 104, and the average VCF (from 10 to 72 h) over all experiments was 12.6 x 104. At very low (1.5 mg/L) added DOM, VCFs dropped by approximately half. At very high (20 mg/L) added DOM, VCFs dropped 10-fold. Presumably, MeHg was bound to a variety of reduced sulfur sites on the DOM, making it unavailable for uptake. Diatoms accumulated significantly more MeHg when exposed to transphilic DOM extracts than hydrophobic ones. However, algal lysate, a labile type of DOM created by resuspending a marine diatom in freshwater, behaved similarly to a refractory DOM isolate from San Francisco Bay. Addition of 67 μM L-cysteine resulted in the largest drop in VCFs, to 0.28 x 104. Although the DOM composition influenced the availability of MeHg to some extent, total DOM concentration was the most important factor in determining algal bioaccumulation of MeHg.

  10. Local proliferation initiates macrophage accumulation in adipose tissue during obesity.

    PubMed

    Zheng, C; Yang, Q; Cao, J; Xie, N; Liu, K; Shou, P; Qian, F; Wang, Y; Shi, Y

    2016-01-01

    Obesity-associated chronic inflammation is characterized by an accumulation of adipose tissue macrophages (ATMs). It is generally believed that those macrophages are derived from peripheral blood monocytes. However, recent studies suggest that local proliferation of macrophages is responsible for ATM accumulation. In the present study, we revealed that both migration and proliferation contribute to ATM accumulation during obesity development. We show that there is a significant increase in ATMs at the early stage of obesity, which is largely due to an enhanced in situ macrophage proliferation. This result was obtained by employing fat-shielded irradiation and bone marrow reconstitution. Additionally, the production of CCL2, a pivotal chemoattractant of monocytes, was not found to be increased at this stage, corroborating with a critical role of proliferation. Nonetheless, as obesity proceeds, the role of monocyte migration into adipose tissue becomes more significant and those new immigrants further proliferate locally. These proliferating ATMs mainly reside in crown-like structures formed by macrophages surrounding dead adipocytes. We further showed that IL-4/STAT6 is a driving force for ATM proliferation. Therefore, we demonstrated that local proliferation of resident macrophages contributes to ATM accumulation during obesity development and has a key role in obesity-associated inflammation. PMID:27031964

  11. Higher Education in Virginia.

    ERIC Educational Resources Information Center

    Virginia State Council of Higher Education, Richmond.

    For the past 7 years, the State Council of Higher Education has published a report of selected characteristics and degree programs for Virginia's state-supported colleges and universities. By combining data from independent institutions with information collected from the state-supported colleges, a more comprehensive picture of higher education…

  12. Minorities in Higher Education.

    ERIC Educational Resources Information Center

    Justiz, Manuel J., Ed.; And Others

    This book presents 19 papers on efforts to increase the participation of members of minority groups in higher education. The papers are: (1) "Demographic Trends and the Challenges to American Higher Education" (Manuel Justiz); (2) "Three Realities: Minority Life in the United States--The Struggle for Economic Equity (adapted by Don M. Blandin);…

  13. Hypermedia and Higher Education.

    ERIC Educational Resources Information Center

    Lemke, Jay L.

    1993-01-01

    Discusses changes in higher education that are resulting from the use of hypermedia. Topics addressed include the structure of traditional texts; a distributed model for academic communication; independent learning as a model for higher education; skills for hypermedia literacy; database searching; information retrieval; authoring skills; design…

  14. Reinventing Higher Education

    ERIC Educational Resources Information Center

    Hayes, Dianne

    2012-01-01

    Higher education institutions are in the battle of a lifetime as they are coping with political and economic uncertainties, threats to federal aid, declining state support, higher tuition rates and increased competition from for-profit institutions. Amid all these challenges, these institutions are pressed to keep up with technological demands,…

  15. Higher Education Exchange

    ERIC Educational Resources Information Center

    Brown, David W., Ed.; Witte, Deborah, Ed.

    2009-01-01

    This volume begins with an essay by Noelle McAfee, a contributor who is familiar to readers of Higher Education Exchange (HEX). She reiterates Mathews' argument regarding the disconnect between higher education's sense of engagement and the public's sense of engagement, and suggests a way around the epistemological conundrum of "knowledge produced…

  16. Higher Education Exchange, 2009

    ERIC Educational Resources Information Center

    Brown, David W., Ed.; Witte, Deborah, Ed.

    2009-01-01

    This volume begins with an essay by Noelle McAfee, a contributor who is familiar to readers of Higher Education Exchange (HEX). She reiterates Kettering's president David Mathews' argument regarding the disconnect between higher education's sense of engagement and the public's sense of engagement, and suggests a way around the epistemological…

  17. PHOENIX. Higher Wage Careers.

    ERIC Educational Resources Information Center

    Bismarck State Coll., ND.

    This document outlines the curriculum plan for the one-semester vocational-technical training component of PHOENIX: A Model Program for Higher-Wage Potential Careers offered by Bismarck State College (North Dakota) which prepares and/or retrains individuals for higher-wage technical careers. The comprehensive model for the program is organized…

  18. Higher Education Exchange 2006

    ERIC Educational Resources Information Center

    Brown, David W., Ed.; Witte, Deborah, Ed.

    2006-01-01

    Contributors to this issue of the Higher Education Exchange debate the issues around knowledge production, discuss the acquisition of deliberative skills for democracy, and examine how higher education prepares, or does not prepare, students for citizenship roles. Articles include: (1) "Foreword" (Deborah Witte); (2) "Knowledge, Judgment and…

  19. Reimagining Christian Higher Education

    ERIC Educational Resources Information Center

    Hulme, E. Eileen; Groom, David E., Jr.; Heltzel, Joseph M.

    2016-01-01

    The challenges facing higher education continue to mount. The shifting of the U.S. ethnic and racial demographics, the proliferation of advanced digital technologies and data, and the move from traditional degrees to continuous learning platforms have created an unstable environment to which Christian higher education must adapt in order to remain…

  20. Gender and Higher Education

    ERIC Educational Resources Information Center

    Bank, Barbara J., Ed.

    2011-01-01

    This comprehensive, encyclopedic review explores gender and its impact on American higher education across historical and cultural contexts. Challenging recent claims that gender inequities in U.S. higher education no longer exist, the contributors--leading experts in the field--reveal the many ways in which gender is embedded in the educational…

  1. China's Higher Education Expansion and the Task of Economic Revitalization

    ERIC Educational Resources Information Center

    Wang, Xiaoyan; Liu, Jian

    2011-01-01

    This paper centers on the expansion from elite to mass higher education in China and its effects on China's economic development. These effects are twofold, including both the immediate influence of expanded enrollment in higher education on China's economy, and the human capital accumulation for the long term. The paper first provides a…

  2. Chesapeake bay anoxia: origin, development, and significance.

    PubMed

    Officer, C B; Biggs, R B; Taft, J L; Cronin, L E; Tyler, M A; Boynton, W R

    1984-01-01

    Anoxia occurs annually in deeper waters of the central portion of the Chesapeake Bay and presently extends from Baltimore to the mouth of the Potomac estuary. This condition, which encompasses some 5 billion cubic meters of water and lasts from May to September, is the result of increased stratification of the water column in early spring, with consequent curtailment of reoxygenation of the bottom waters across the halocline, and benthic decay of organic detritus accumulated from plankton blooms of the previous summer and fall. The Chesapeake Bay anoxia appears to have had significant ecological effects on many marine species, including several of economic importance. PMID:17752972

  3. Chesapeake Bay anoxia: origin, development, and significance

    SciTech Connect

    Officer, C.B.; Biggs, R.B.; Taft, J.L.; Cronin, L.E.; Tyler, M.A.; Boynton, W.R.

    1984-01-06

    Anoxia occurs annually in deeper waters of the central portion of the Chesapeake Bay and presently extends from Baltimore to the mouth of the Potomac estuary. This condition, which encompasses some 5 billion cubic meters of water and lasts from May to September, is the result of increased stratification of the water column in early spring, with consequent curtailment of reoxygenation of the bottom waters across the halocline, and benthic decay of organic detritus accumulated from plankton blooms of the previous summer and fall. The Chesapeake Bay anoxia appears to have had significant ecological effects on many marine species, including several of economic importance. 43 references, 7 figures, 1 table.

  4. Accumulation of the Antibiotic Phenazine-1-Carboxylic Acid in the Rhizosphere of Dryland Cereals

    PubMed Central

    Mavrodi, Dmitri V.; Mavrodi, Olga V.; Parejko, James A.; Bonsall, Robert F.; Kwak, Youn-Sig; Paulitz, Timothy C.; Weller, David M.

    2012-01-01

    Natural antibiotics are thought to function in the defense, fitness, competitiveness, biocontrol activity, communication, and gene regulation of microorganisms. However, the scale and quantitative aspects of antibiotic production in natural settings are poorly understood. We addressed these fundamental questions by assessing the geographic distribution of indigenous phenazine-producing (Phz+) Pseudomonas spp. and the accumulation of the broad-spectrum antibiotic phenazine-1-carboxylic acid (PCA) in the rhizosphere of wheat grown in the low-precipitation zone (<350 mm) of the Columbia Plateau and in adjacent, higher-precipitation areas. Plants were collected from 61 commercial wheat fields located within an area of about 22,000 km2. Phz+ Pseudomonas spp. were detected in all sampled fields, with mean population sizes ranging from log 3.2 to log 7.1 g−1 (fresh weight) of roots. Linear regression analysis demonstrated a significant inverse relationship between annual precipitation and the proportion of plants colonized by Phz+ Pseudomonas spp. (r2 = 0.36, P = 0.0001). PCA was detected at up to nanomolar concentrations in the rhizosphere of plants from 26 of 29 fields that were selected for antibiotic quantitation. There was a direct relationship between the amount of PCA extracted from the rhizosphere and the population density of Phz+ pseudomonads (r2 = 0.46, P = 0.0006). This is the first demonstration of accumulation of significant quantities of a natural antibiotic across a terrestrial ecosystem. Our results strongly suggest that natural antibiotics can transiently accumulate in the plant rhizosphere in amounts sufficient not only for inter- and intraspecies signaling but also for the direct inhibition of sensitive organisms. PMID:22138981

  5. Health hazards and heavy metals accumulation by summer squash (Cucurbita pepo L.) cultivated in contaminated soils.

    PubMed

    Galal, Tarek M

    2016-07-01

    The present study was carried out to investigate the heavy metal concentration accumulated by summer squash cultivated in contaminated soil and their health hazards for public consumers at south Cairo Province, Egypt. Soil and plants were sampled from contaminated and reference farms, using 1 m(2) quadrats, for biomass estimation and nutrient analysis. The daily intake of metals (DIM) and health risk index (HRI) were estimated. Significant differences in soil variables (except As) between contaminated and reference sites were recognized. Summer squash showed remarkable reduction in fresh and dry biomass, fruit production, and photosynthetic pigments under pollution stress. The inorganic and organic nutrients in the aboveground and belowground parts showed significant reduction in contaminated site. In addition, higher concentrations of heavy metals were accumulated in the edible parts and roots more than shoots. The bioaccumulation factor of summer squash for investigated metals was greater than 1, while the translocation factor did not exceed unity in both contaminated and reference sites. The DIM for all investigated metals in the reference site and in the contaminated site (except Fe and Mn) did not exceed 1 in both adults and children. However, HRI of Ni and Mn in the reference site and Pb, Cd, Cu, Ni, Fe, Mn, and Zn in the contaminated one exceeded unity indicating great potential to pose health risk to the consumers. The author recommends that people living in the contaminated area should not eat large quantities of summer squash, so as to avoid excess accumulation of heavy metals in their bodies. PMID:27344559

  6. PCB accumulation in Hudson River pumpkinseed sunfish and bullhead: Influences of invertebrate prey

    SciTech Connect

    Feldman, R.S.

    1992-01-01

    Hudson River sediments are contaminated with PCBs, and these toxic compounds are also in the water and have accumulated in food chains. The relative importance of exposure by fish to contaminated water vs. contaminated prey was unknown. further, is was not known if difference in diet could influence fish PCB levels. Invertebrates and fish were sampled in different habitats to address these issues. Invertebrate communities differed in several ecological measures between two different plant beds, and among experimentally manipulated habitats in one plant bed. Communities often differed significantly in parameters such as total invertebrate density, densities of individual taxa, taxonomic richness and similarity, and size distributions; some taxa were also absent from one habitat but present in another. Total PCBs differed significantly for invertebrate communities between the two plant beds (9.4 vs. 31.4 [mu]g/g), and between some of the communities in the manipulated habitats (1.8 vs 5.3 [mu]g/g). These differences did not translate into difference in PCBs among fish that fed in the different habitats. However, bullhead had significantly higher levels than pumpkinseed (15.4 vs. 6.9 [mu]g/g). Yearling pumpkinseed that fed on Hudson River invertebrates had 5x the PCB levels of pumpkinseed exposed for the same period to the water but not to the prey, and 18x as much PCBs as fish unexposed to either Hudson River water or prey. Further, fish that fed on local prey had a higher proportion of high-Cl isomers than those exposed only to the contaminated water. Fish that fed in different habitats did not have different PCB levels. Thus, the role of diet needs further experimentation, but it is clear that local prey are the major route for PCB accumulation in yearling pumpkinseed.

  7. Identification of genes associated with chlorophyll accumulation in flower petals.

    PubMed

    Ohmiya, Akemi; Hirashima, Masumi; Yagi, Masafumi; Tanase, Koji; Yamamizo, Chihiro

    2014-01-01

    Plants have an ability to prevent chlorophyll accumulation, which would mask the bright flower color, in their petals. In contrast, leaves contain substantial amounts of chlorophyll, as it is essential for photosynthesis. The mechanisms of organ-specific chlorophyll accumulation are unknown. To identify factors that determine the chlorophyll content in petals, we compared the expression of genes related to chlorophyll metabolism in different stages of non-green (red and white) petals (very low chlorophyll content), pale-green petals (low chlorophyll content), and leaves (high chlorophyll content) of carnation (Dianthus caryophyllus L.). The expression of many genes encoding chlorophyll biosynthesis enzymes, in particular Mg-chelatase, was lower in non-green petals than in leaves. Non-green petals also showed higher expression of genes involved in chlorophyll degradation, including STAY-GREEN gene and pheophytinase. These data suggest that the absence of chlorophylls in carnation petals may be caused by the low rate of chlorophyll biosynthesis and high rate of degradation. Similar results were obtained by the analysis of Arabidopsis microarray data. In carnation, most genes related to chlorophyll biosynthesis were expressed at similar levels in pale-green petals and leaves, whereas the expression of chlorophyll catabolic genes was higher in pale-green petals than in leaves. Therefore, we hypothesize that the difference in chlorophyll content between non-green and pale-green petals is due to different levels of chlorophyll biosynthesis. Our study provides a basis for future molecular and genetic studies on organ-specific chlorophyll accumulation.

  8. Soluble extract of soybean fermented with Aspergillus oryzae GB107 inhibits fat accumulation in cultured 3T3-L1 adipocytes

    PubMed Central

    So, Kyoung-Ha; Suzuki, Yasuki; Yonekura, Shinichi; Suzuki, Yutaka; Lee, Chan Ho; Kim, Sung Woo; Katoh, Kazuo

    2015-01-01

    BACKGROUND/OBJECTIVES This study was conducted to investigate the effects of fermented soybean (FS) extract on adipocyte differentiation and fat accumulation using cultured 3T3-L1 adipocytes. MATERIALS/METHODS 3T3-L1 adipocytes were treated with FS and nonfermented soybean (NFS) extract during differentiation for 10 days in vitro. Oil red O staining was performed and glycerol-3-phosphate dehydrogenase (GPDH) activity was measured for analysis of fat accumulation. Expressions of adipogenic genes were measured. RESULTS Soluble extract of soybean fermented with Aspergillus oryzae GB107 contained higher levels of low-molecular-weight protein than conventional soybean protein did. FS extract (50 µg/ml) inhibited adipocyte differentiation and fat accumulation during differentiation of 3T3-L1 preadipocytes for 10 days in vitro. Significantly lower GPDH activity was observed in differentiated adipocytes treated with the FS extract than those treated with NFS extract. Treatment with FS extract resulted in decreased expression levels of leptin, adiponectin, and adipogenin genes, which are associated with adipogenesis. CONCLUSIONS This report is the first to demonstrate that the water-soluble extract from FS inhibits fat accumulation and lipid storage in 3T3-L1 adipocytes. Thus, the soybean extract fermented with A. oryzae GB107 could be used to control lipid accumulation in adipocytes. PMID:26244085

  9. Loss of Ceramide Kinase in Arabidopsis Impairs Defenses and Promotes Ceramide Accumulation and Mitochondrial H2O2 Bursts[C][W

    PubMed Central

    Bi, Fang-Cheng; Liu, Zhe; Wu, Jian-Xin; Liang, Hua; Xi, Xue-Li; Fang, Ce; Sun, Tie-Jun; Yin, Jian; Dai, Guang-Yi; Rong, Chan; Greenberg, Jean T.; Su, Wei-Wei; Yao, Nan

    2014-01-01

    Arabidopsis thaliana plants that lack ceramide kinase, encoded by ACCELERATED CELL DEATH5 (ACD5), display spontaneous programmed cell death late in development and accumulate substrates of ACD5. Here, we compared ceramide accumulation kinetics, defense responses, ultrastructural features, and sites of reactive oxygen species (ROS) production in wild-type and acd5 plants during development and/or Botrytis cinerea infection. Quantitative sphingolipid profiling indicated that ceramide accumulation in acd5 paralleled the appearance of spontaneous cell death, and it was accompanied by autophagy and mitochondrial ROS accumulation. Plants lacking ACD5 differed significantly from the wild type in their responses to B. cinerea, showing earlier and higher increases in ceramides, greater disease, smaller cell wall appositions (papillae), reduced callose deposition and apoplastic ROS, and increased mitochondrial ROS. Together, these data show that ceramide kinase greatly affects sphingolipid metabolism and the site of ROS accumulation during development and infection, which likely explains the developmental and infection-related cell death phenotypes. The acd5 plants also showed an early defect in restricting B. cinerea germination and growth, which occurred prior to the onset of cell death. This early defect in B. cinerea restriction in acd5 points to a role for ceramide phosphate and/or the balance of ceramides in mediating early antifungal responses that are independent of cell death. PMID:25149397

  10. Frontal cortical mitochondrial dysfunction and mitochondria-related β-amyloid accumulation by chronic sleep restriction in mice

    PubMed Central

    Zhao, Hongyi; He, Jialin; Zhuang, Jianhua; Liu, Zhenyu; Yang, Yang; Huang, Liuqing; Zhao, Zhongxin

    2016-01-01

    Mitochondrial dysfunction induced by mitochondria-related β-amyloid (Aβ) accumulation is increasingly being considered a novel risk factor for sporadic Alzheimer’s disease pathophysiology. The close relationship between chronic sleep restriction (CSR) and cortical Aβ elevation was confirmed recently. By assessing frontal cortical mitochondrial function (electron microscopy manifestation, cytochrome C oxidase concentration, ATP level, and mitochondrial membrane potential) and the levels of mitochondria-related Aβ in 9-month-old adult male C57BL/6J mice subjected to CSR and as an environmental control (CO) group, we aimed to evaluate the association of CSR with mitochondrial dysfunction and mitochondria-related Aβ accumulation. In this study, frontal cortical mitochondrial dysfunction was significantly more severe in CSR mice compared with CO animals. Furthermore, CSR mice showed higher mitochondria-associated Aβ, total Aβ, and mitochondria-related β-amyloid protein precursor (AβPP) levels compared with CO mice. In the CSR model, mouse frontal cortical mitochondrial dysfunction was correlated with mitochondria-associated Aβ and mitochondria-related AβPP levels. However, frontal cortical mitochondria-associated Aβ levels showed no significant association with cortical total Aβ and mitochondrial AβPP concentrations. These findings indicated that CSR-induced frontal cortical mitochondrial dysfunction and mitochondria-related Aβ accumulation, which was closely related to mitochondrial dysfunction under CSR. PMID:27341212

  11. Accumulation and translocation of metals in soil and different parts of French bean (Phaseolus vulgaris L.) amended with sewage sludge.

    PubMed

    Kumar, Vinod; Chopra, A K

    2014-01-01

    A pot experiment was conducted to study the accumulation and translocation of metals in French bean (Phaseolus vulgaris L.). Plants were grown in soil amended with up to 100 % sewage sludge. Significant (p < 0.01) changes to soil characteristics were observed. The maximum growth of P. vulgaris was noted in the treatment with 40 % of sewage sludge. Metal concentrations were significantly (p < 0.05) higher in P. vulgaris after sewage sludge amendment where Fe > Zn > Cd > Cu > Cr > Pb. The translocation for Fe and Zn was in the order of leaves > shoot > root > fruits, for Cd, shoot > root > leaves > fruits, for Cu and Pb shoot > leaves > root > fruits and for Cr root > shoot > leaves > fruits of P. vulgaris. All accumulated metal concentrations except Cd in the fruit were below the FAO/WHO standard limits. Thus, the amendment of agricultural soil by sewage sludge might be feasible. However, a regular monitoring of metal levels in agricultural products is recommended to prevent their accumulation in the food chain.

  12. Frontal cortical mitochondrial dysfunction and mitochondria-related β-amyloid accumulation by chronic sleep restriction in mice.

    PubMed

    Zhao, Hongyi; Wu, Huijuan; He, Jialin; Zhuang, Jianhua; Liu, Zhenyu; Yang, Yang; Huang, Liuqing; Zhao, Zhongxin

    2016-08-17

    Mitochondrial dysfunction induced by mitochondria-related β-amyloid (Aβ) accumulation is increasingly being considered a novel risk factor for sporadic Alzheimer's disease pathophysiology. The close relationship between chronic sleep restriction (CSR) and cortical Aβ elevation was confirmed recently. By assessing frontal cortical mitochondrial function (electron microscopy manifestation, cytochrome C oxidase concentration, ATP level, and mitochondrial membrane potential) and the levels of mitochondria-related Aβ in 9-month-old adult male C57BL/6J mice subjected to CSR and as an environmental control (CO) group, we aimed to evaluate the association of CSR with mitochondrial dysfunction and mitochondria-related Aβ accumulation. In this study, frontal cortical mitochondrial dysfunction was significantly more severe in CSR mice compared with CO animals. Furthermore, CSR mice showed higher mitochondria-associated Aβ, total Aβ, and mitochondria-related β-amyloid protein precursor (AβPP) levels compared with CO mice. In the CSR model, mouse frontal cortical mitochondrial dysfunction was correlated with mitochondria-associated Aβ and mitochondria-related AβPP levels. However, frontal cortical mitochondria-associated Aβ levels showed no significant association with cortical total Aβ and mitochondrial AβPP concentrations. These findings indicated that CSR-induced frontal cortical mitochondrial dysfunction and mitochondria-related Aβ accumulation, which was closely related to mitochondrial dysfunction under CSR.

  13. Specificity of accumulation and transmission of tomato spotted wilt virus (TSWV) in two genera, Frankliniella and Thrips (Thysanoptera: Thripidae).

    PubMed

    Inoue, T; Sakurai, T; Murai, T; Maeda, T

    2004-12-01

    The accumulation and transmission of tomato spotted wilt virus (TSWV) was examined in second instar larvae and adults of two thrips genera, Frankliniella and Thrips. The species tested were F. occidentalis (Pergande), F. intonsa (Trybom), T. tabaciLindeman, T. setosus Moulton, T. palmi Karny and T. hawaiiensis (Morgan). In a standard petunia leaf disc assay, the efficiencies of TSWV transmission by two species of Frankliniella were higher than those of any Thrips species in the adult stage. A triple antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA) showed that large amounts of the TSWV-nucleocapsid (N) protein were present in the ELISA-positive larvae of each species, with the exception of T. palmi. The ELISA titre of and the proportion of virus-infected individuals of the two Frankliniella species increased or did not significantly change from the larval to the adult stages, whereas those of the four Thrips species decreased significantly. These results show that the specificity of virus transmission by adult thrips is probably affected by the amount of viral N protein accumulation in the adults and that the accumulation pattern from the larval to the adult stages is in between the two genera tested in the present study.

  14. Red mud (RM)-Induced enhancement of iron plaque formation reduces arsenic and metal accumulation in two wetland plant species.

    PubMed

    Yang, J X; Guo, Q J; Yang, J; Zhou, X Y; Ren, H Y; Zhang, H Z; Xu, R X; Wang, X D; Peters, M; Zhu, G X; Wei, R F; Tian, L Y; Han, X K

    2016-01-01

    Human activities have resulted in arsenic (As) and heavy metals accumulation in paddy soils in China. Phytoremediation has been suggested as an effective and low-cost method to clean up contaminated soils. A combined soil-sand pot experiment was conducted to investigate the influence of red mud (RM) supply on iron plaque formation and As and heavy metal accumulation in two wetland plant species (Cyperus alternifolius Rottb., Echinodorus amazonicus Rataj), using As and heavy metals polluted paddy soil combined with three rates of RM application (0, 2%, 5%). The results showed that RM supply significantly decreased As and heavy metals accumulation in shoots of the two plants due to the decrease of As and heavy metal availability and the enhancement of the formation of iron plaque on the root surface and in the rhizosphere. Both wetland plants supplied with RM tended to have more Fe plaque, higher As and heavy metals on roots and in their rhizospheres, and were more tolerant of As and heavy metal toxicity. The results suggest that RM-induced enhancement of the formation of iron plaque on the root surface and in the rhizosphere of wetland plants may be significant for remediation of soils contaminated with As and heavy metals. PMID:26505322

  15. Nonalcoholic Lipid Accumulation and Hepatocyte Malignant Transformation

    PubMed Central

    Gu, Juanjuan; Yao, Min; Yao, Dengbing; Wang, Li; Yang, Xuli; Yao, Dengfu

    2016-01-01

    Abstract Worldwide incidence of hepatocellular carcinoma (HCC) is steadily increasing, highlighting its status as a public health concern, particularly due to its significant association with other comorbidities, such as diabetes. However, nonalcoholic fatty liver disease (NAFLD) has emerged as a primary risk factor, with its own prevalence increasing in recent years, and it has gradually caught up with the historical primary etiological factors of infection with hepatitis B virus and hepatitis C virus, exposure to aflatoxin, or alcohol liver disease. The deeply worrisome aspects of all of these high risk factors, however, are their remarkable presence within populations. Systemic and genetic mechanisms involved in the malignant transformation of liver cells, as well as useful biomarkers of early stage HCC are being investigated. However, the exact mechanisms underlying the interrelation of NAFLD and HCC remain largely unknown. In this review, some of the recent advances in our understanding of liver lipid accumulation are summarized and discussed to provide insights into the relationship between NAFLD and hepatocyte malignant transformation. PMID:27350942

  16. Vinpocetine attenuates lipid accumulation and atherosclerosis formation

    SciTech Connect

    Cai, Yujun; Li, Jian-Dong; Yan, Chen

    2013-05-10

    Highlights: •Vinpocetine attenuates hyperlipidemia-induced atherosclerosis in a mouse model. •Vinpocetine antagonizes ox-LDL uptake and accumulation in macrophages. •Vinpocetine blocks the induction of ox-LDL receptor LOX-1 in vitro and in vivo. -- Abstract: Atherosclerosis, the major cause of myocardial infarction and stroke, is a chronic arterial disease characterized by lipid deposition and inflammation in the vessel wall. Cholesterol, in low-density lipoprotein (LDL), plays a critical role in the pathogenesis of atherosclerosis. Vinpocetine, a derivative of the alkaloid vincamine, has long been used as a cerebral blood flow enhancer for treating cognitive impairment. Recent study indicated that vinpocetine is a potent anti-inflammatory agent. However, its role in the pathogenesis of atherosclerosis remains unexplored. In the present study, we show that vinpocetine significantly reduced atherosclerotic lesion formation in ApoE knockout mice fed with a high-fat diet. In cultured murine macrophage RAW264.7 cells, vinpocetine markedly attenuated oxidized LDL (ox-LDL) uptake and foam cell formation. Moreover, vinpocetine greatly blocked the induction of ox-LDL receptor 1 (LOX-1) in cultured macrophages as well as in the LOX-1 level in atherosclerotic lesions. Taken together, our data reveal a novel role of vinpocetine in reduction of pathogenesis of atherosclerosis, at least partially through suppressing LOX-1 signaling pathway. Given the excellent safety profile of vinpocetine, this study suggests vinpocetine may be a therapeutic candidate for treating atherosclerosis.

  17. Trehalose Accumulation Triggers Autophagy during Plant Desiccation

    PubMed Central

    Moghaddam, Lalehvash; Long, Hao; Dickman, Martin B; Zhang, Xiuren; Mundree, Sagadevan

    2015-01-01

    Global climate change, increasingly erratic weather and a burgeoning global population are significant threats to the sustainability of future crop production. There is an urgent need for the development of robust measures that enable crops to withstand the uncertainty of climate change whilst still producing maximum yields. Resurrection plants possess the unique ability to withstand desiccation for prolonged periods, can be restored upon watering and represent great potential for the development of stress tolerant crops. Here, we describe the remarkable stress characteristics of Tripogon loliiformis, an uncharacterised resurrection grass and close relative of the economically important cereals, rice, sorghum, and maize. We show that T. loliiformis survives extreme environmental stress by implementing autophagy to prevent Programmed Cell Death. Notably, we identified a novel role for trehalose in the regulation of autophagy in T.loliiformis. Transcriptome, Gas Chromatography Mass Spectrometry, immunoblotting and confocal microscopy analyses directly linked the accumulation of trehalose with the onset of autophagy in dehydrating and desiccated T. loliiformis shoots. These results were supported in vitro with the observation of autophagosomes in trehalose treated T. loliiformis leaves; autophagosomes were not detected in untreated samples. Presumably, once induced, autophagy promotes desiccation tolerance in T.loliiformis, by removal of cellular toxins to suppress programmed cell death and the recycling of nutrients to delay the onset of senescence. These findings illustrate how resurrection plants manipulate sugar metabolism to promote desiccation tolerance and may provide candidate genes that are potentially useful for the development of stress tolerant crops. PMID:26633550

  18. Accumulation and Toxicity of CuO and ZnO Nanoparticles through Waterborne and Dietary Exposure of Goldfish (Carassius auratus)

    PubMed Central

    Ates, Mehmet; Arslan, Zikri; Demir, Veysel; Daniels, James; Farah, Ibrahim O.

    2014-01-01

    Dietary and waterborne exposure to CuO and ZnO nanoparticles (NPs) was conducted using a simplified model of an aquatic food chain consisting of zooplankton (Artemia salina) and goldfish (Carassius auratus) to determine bioaccumulation, toxic effects and particle transport through trophic levels. Artemia contaminated with NPs were used as food in dietary exposure. Fish were exposed to suspensions of the NPs in waterborne exposure. ICP-MS analysis showed that accumulation primarily occurred in the intestine, followed by the gills and liver. Dietary uptake was lower, but was found to be a potential pathway for transport of NPs to higher organisms. Waterborne exposure resulted in about a tenfold higher accumulation in the intestine. The heart, brain and muscle tissue had no significant Cu or Zn. However, concentrations in muscle increased with NP concentration, which was ascribed to bioaccumulation of Cu and Zn released from NPs. Free Cu concentration in the medium was always higher than that of Zn, indicating CuO NPs dissolved more readily. ZnO NPs were relatively benign, even in waterborne exposure (p≥0.05). In contrast, CuO NPs were toxic. Malondialdehyde levels in the liver and gills increased substantially (p<0.05). Despite lower Cu accumulation, the liver exhibited significant oxidative stress, which could be from chronic exposure to Cu ions. PMID:24860999

  19. Accumulation and toxicity of CuO and ZnO nanoparticles through waterborne and dietary exposure of goldfish (Carassius auratus).

    PubMed

    Ates, Mehmet; Arslan, Zikri; Demir, Veysel; Daniels, James; Farah, Ibrahim O

    2015-01-01

    Dietary and waterborne exposure to copper oxide (CuO) and zinc oxide (ZnO) nanoparticles (NPs) was conducted using a simplified model of an aquatic food chain consisting of zooplankton (Artemia salina) and goldfish (Carassius auratus) to determine bioaccumulation, toxic effects, and particle transport through trophic levels. Artemia contaminated with NPs were used as food in dietary exposure. Fish were exposed to suspensions of the NPs in waterborne exposure. ICP-MS analysis showed that accumulation primarily occurred in the intestine, followed by the gills and liver. Dietary uptake was lower, but was found to be a potential pathway for transport of NPs to higher organisms. Waterborne exposure resulted in about a 10-fold higher accumulation in the intestine. The heart, brain, and muscle tissue had no significant Cu or Zn. However, concentrations in muscle increased with NP concentration, which was ascribed to bioaccumulation of Cu and Zn released from NPs. Free Cu concentration in the medium was always higher than that of Zn, indicating CuO NPs dissolved more readily. ZnO NPs were relatively benign, even in waterborne exposure (p ≥ 0.05). In contrast, CuO NPs were toxic. Malondialdehyde levels in the liver and gills increased substantially (p < 0.05). Despite lower Cu accumulation, the liver exhibited significant oxidative stress, which could be from chronic exposure to Cu ions.

  20. Effects of exogenous glycinebetaine and trehalose on lead accumulation in an aquatic plant (Lemna gibba L.).

    PubMed

    Duman, Fatih

    2011-01-01

    This study was aimed at investigating and comparing the effects of exogenous glycinebetaine (GB) and trehalose (TR) on lead (Pb) accumulation in Lemna gibba. Two-way ANOVA showed that both GB and TR had significant effects on Pb accumulation. However, TR seemed to be more effective than GB. It was determined that 5 mM GB application decreased Pb accumulation whereas 0.5 mM TR increased and 2 and 5 mM decreased Pb accumulation. The results obtained from this study will be useful for examining the phytoremediation of polluted water using aquatic plants. PMID:21598778

  1. Accumulations of Ca/P in the core of hairs from Taklamakan desert mummies

    NASA Astrophysics Data System (ADS)

    Hallégot, P.; Walter, P.; Cotte, M.; Audinot, J.-N.; Guillot, J.; Migeon, H.-N.; Tallarek, E.; Hagenhoff, B.

    2008-12-01

    Hairs from mummies discovered in the west China Taklamakan desert are investigated by NanoSIMS, ToF-SIMS, Auger and TEM. Intra-medullar accumulations of calcium and phosphorus are described. The present study is an attempt to understand the significance of these accumulations. Their possible exogenous or endogenous origin is debated. Moreover, TEM revealed a particular nature of the accumulation that decorates a fibrilar structure of the medullar. To what extent did molecular control govern the particle growth and does such an accumulation represent a step toward the mineralization of the keratinized fiber?

  2. Nitrate losses, nutrients and heavy metal accumulation from substrates assembled for urban soils reconstruction.

    PubMed

    Civeira, G; Lavado, R S

    2008-09-01

    Urban soils may suffer mild to severe degradation as a result of physical and chemical alterations. To reconstruct these soils, a new upper horizon must be created, usually through the application of organic matter, one source of which is biosolids. Different soil mixtures were evaluated with regard to loss of nitrates in percolates and the uptake and incorporation of nutrients and heavy metals into plant tissues. The experiment was conducted in trays; treatments were mixtures of biosolids and a coarse material (e.g., sand or pine wood sawdust), combined in different proportions. Randomized trays were seeded with a mix of tall fescue (Festuca arundinacea L.) and perennial ryegrass (Lolium perenne L.). Plant biomass was quantified. Nitrates in percolates were measured, as were nutrients and heavy metals in mixtures and plant tissues. Plants accumulated substantially more N, and biomass was 40% higher, in the treatments with higher levels of biosolids. The same treatments released more nitrogen and resulted in higher percolate nitrate levels. Plants had normal concentrations of all nutrients, except nitrogen, which was low. Heavy metal concentrations were not significantly different among treatments. Based on the analysis of these data, the proportion of biosolids appears to be the most important factor affecting the quality of reconstructed soil and the rate of improvement. The type of coarse material used did not significantly affect the outcome.

  3. Gene limiting cadmium accumulation in rice.

    PubMed

    Ueno, Daisei; Yamaji, Naoki; Kono, Izumi; Huang, Chao Feng; Ando, Tsuyu; Yano, Masahiro; Ma, Jian Feng

    2010-09-21

    Intake of toxic cadmium (Cd) from rice caused Itai-itai disease in the past and it is still a threat for human health. Therefore, control of the accumulation of Cd from soil is an important food-safety issue, but the molecular mechanism for the control is unknown. Herein, we report a gene (OsHMA3) responsible for low Cd accumulation in rice that was isolated from a mapping population derived from a cross between a high and low Cd-accumulating cultivar. The gene encodes a transporter belonging to the P(1B)-type ATPase family, but shares low similarity with other members. Heterologous expression in yeast showed that the transporter from the low-Cd cultivar is functional, but the transporter from the high-Cd cultivar had lost its function, probably because of the single amino acid mutation. The transporter is mainly expressed in the tonoplast of root cells at a similar level in both the low and high Cd-accumulating cultivars. Overexpression of the functional gene from the low Cd-accumulating cultivar selectively decreased accumulation of Cd, but not other micronutrients in the grain. Our results indicated that OsHMA3 from the low Cd-accumulating cultivar limits translocation of Cd from the roots to the above-ground tissues by selectively sequestrating Cd into the root vacuoles.

  4. [Effects of enhanced ammonium nutrition on content and accumulation of nitrogen and mineral nutrients in wheat plant].

    PubMed

    Dai, Tingbo; Cao, Weixing; Sun, Chuanfan

    2002-03-01

    The hydroponics experiment was conducted to study the nutrition basis for growth promotion of wheat by Enhanced Ammonium Nutrition(EAN). Compared with fertilizing NO3- alone, EAN significantly increased N concentration and accumulation in leaves, sheaths, and whole plant, but there were not significant effects on roots. EAN had no significant effects on concentration of P and K, but decreased that of Ca and Mg in whole plant. EAN increased accumulation of P, K, and Ca in whole plant, and decreased that of Mg, whereas single NH4+ decreased accumulation of all mineral nutrients. EAN had different effects on accumulation of mineral nutrients in different genotypes. Compared with fertilizing NO3- alone, EAN increased accumulation of P, K, and Ca of YM158 and LZ953. For the accumulation of JDM, there was little responsive to EAN. These results indicated that EAN promoted N absorption and increased accumulation of N, P, K, and Ca in whole plant.

  5. Targeting acid sphingomyelinase reduces cardiac ceramide accumulation in the post-ischemic heart.

    PubMed

    Klevstig, Martina; Ståhlman, Marcus; Lundqvist, Annika; Scharin Täng, Margareta; Fogelstrand, Per; Adiels, Martin; Andersson, Linda; Kolesnick, Richard; Jeppsson, Anders; Borén, Jan; Levin, Malin C

    2016-04-01

    Ceramide accumulation is known to accompany acute myocardial ischemia, but its role in the pathogenesis of ischemic heart disease is unclear. In this study, we aimed to determine how ceramides accumulate in the ischemic heart and to determine if cardiac function following ischemia can be improved by reducing ceramide accumulation. To investigate the association between ceramide accumulation and heart function, we analyzed myocardial left ventricle biopsies from subjects with chronic ischemia and found that ceramide levels were higher in biopsies from subjects with reduced heart function. Ceramides are produced by either de novo synthesis or hydrolysis of sphingomyelin catalyzed by acid and/or neutral sphingomyelinase. We used cultured HL-1 cardiomyocytes to investigate these pathways and showed that acid sphingomyelinase activity rather than neutral sphingomyelinase activity or de novo sphingolipid synthesis was important for hypoxia-induced ceramide accumulation. We also used mice with a partial deficiency in acid sphingomyelinase (Smpd1(+/-) mice) to investigate if limiting ceramide accumulation under ischemic conditions would have a beneficial effect on heart function and survival. Although we showed that cardiac ceramide accumulation was reduced in Smpd1(+/-) mice 24h after an induced myocardial infarction, this reduction was not accompanied by an improvement in heart function or survival. Our findings show that accumulation of cardiac ceramides in the post-ischemic heart is mediated by acid sphingomyelinase. However, targeting ceramide accumulation in the ischemic heart may not be a beneficial treatment strategy. PMID:26930027

  6. Targeting acid sphingomyelinase reduces cardiac ceramide accumulation in the post-ischemic heart.

    PubMed

    Klevstig, Martina; Ståhlman, Marcus; Lundqvist, Annika; Scharin Täng, Margareta; Fogelstrand, Per; Adiels, Martin; Andersson, Linda; Kolesnick, Richard; Jeppsson, Anders; Borén, Jan; Levin, Malin C

    2016-04-01

    Ceramide accumulation is known to accompany acute myocardial ischemia, but its role in the pathogenesis of ischemic heart disease is unclear. In this study, we aimed to determine how ceramides accumulate in the ischemic heart and to determine if cardiac function following ischemia can be improved by reducing ceramide accumulation. To investigate the association between ceramide accumulation and heart function, we analyzed myocardial left ventricle biopsies from subjects with chronic ischemia and found that ceramide levels were higher in biopsies from subjects with reduced heart function. Ceramides are produced by either de novo synthesis or hydrolysis of sphingomyelin catalyzed by acid and/or neutral sphingomyelinase. We used cultured HL-1 cardiomyocytes to investigate these pathways and showed that acid sphingomyelinase activity rather than neutral sphingomyelinase activity or de novo sphingolipid synthesis was important for hypoxia-induced ceramide accumulation. We also used mice with a partial deficiency in acid sphingomyelinase (Smpd1(+/-) mice) to investigate if limiting ceramide accumulation under ischemic conditions would have a beneficial effect on heart function and survival. Although we showed that cardiac ceramide accumulation was reduced in Smpd1(+/-) mice 24h after an induced myocardial infarction, this reduction was not accompanied by an improvement in heart function or survival. Our findings show that accumulation of cardiac ceramides in the post-ischemic heart is mediated by acid sphingomyelinase. However, targeting ceramide accumulation in the ischemic heart may not be a beneficial treatment strategy.

  7. Prion Protein Accumulation in Lipid Rafts of Mouse Aging Brain

    PubMed Central

    Agostini, Federica; Dotti, Carlos G.; Pérez-Cañamás, Azucena; Ledesma, Maria Dolores; Benetti, Federico; Legname, Giuseppe

    2013-01-01

    The cellular form of the prion protein (PrPC) is a normal constituent of neuronal cell membranes. The protein misfolding causes rare neurodegenerative disorders known as transmissible spongiform encephalopathies or prion diseases. These maladies can be sporadic, genetic or infectious. Sporadic prion diseases are the most common form mainly affecting aging people. In this work, we investigate the biochemical environment in which sporadic prion diseases may develop, focusing our attention on the cell membrane of neurons in the aging brain. It is well established that with aging the ratio between the most abundant lipid components of rafts undergoes a major change: while cholesterol decreases, sphingomyelin content rises. Our results indicate that the aging process modifies the compartmentalization of PrPC. In old mice, this change favors PrPC accumulation in detergent-resistant membranes, particularly in hippocampi. To confirm the relationship between lipid content changes and PrPC translocation into detergent-resistant membranes (DRMs), we looked at PrPC compartmentalization in hippocampi from acid sphingomyelinase (ASM) knockout (KO) mice and synaptosomes enriched in sphingomyelin. In the presence of high sphingomyelin content, we observed a significant increase of PrPC in DRMS. This process is not due to higher levels of total protein and it could, in turn, favor the onset of sporadic prion diseases during aging as it increases the PrP intermolecular contacts into lipid rafts. We observed that lowering sphingomyelin in scrapie-infected cells by using fumonisin B1 led to a 50% decrease in protease-resistant PrP formation. This may suggest an involvement of PrP lipid environment in prion formation and consequently it may play a role in the onset or development of sporadic forms of prion diseases. PMID:24040215

  8. Acetamiprid Accumulates in Different Amounts in Murine Brain Regions.

    PubMed

    Terayama, Hayato; Endo, Hitoshi; Tsukamoto, Hideo; Matsumoto, Koichi; Umezu, Mai; Kanazawa, Teruhisa; Ito, Masatoshi; Sato, Tadayuki; Naito, Munekazu; Kawakami, Satoshi; Fujino, Yasuhiro; Tatemichi, Masayuki; Sakabe, Kou

    2016-01-01

    Neonicotinoids such as acetamiprid (ACE) belong to a new and widely used single class of pesticides. Neonicotinoids mimic the chemical structure of nicotine and share agonist activity with the nicotine acetylcholine receptor (nAchR). Neonicotinoids are widely considered to be safe in humans; however, they have recently been implicated in a number of human health disorders. A wide range of musculoskeletal and neuromuscular disorders associated with high doses of neonicotinoids administered to animals have also been reported. Consequently, we used a mouse model to investigate the response of the central nervous system to ACE treatment. Our results show that exposure to ACE-containing water for three or seven days (decuple and centuple of no observable adverse effect level (NOAEL)/day) caused a decrease in body weight in 10-week old A/JJmsSlc (A/J) mice. However, the treatments did not affect brain histology or expression of CD34. ACE concentrations were significantly higher in the midbrain of ACE-treated mice than that of the normal and vehicle groups. Expression levels of α7, α4, and β2 nAChRs were found to be low in the olfactory bulb and midbrain of normal mice. Furthermore, in the experimental group (centuple ACE-containing water for seven days), β2 nAChR expression decreased in many brain regions. Information regarding the amount of accumulated ACE and expression levels of the acetylcholine receptor in each region of the brain is important for understanding any clinical symptoms that may be associated with ACE exposure. PMID:27669271

  9. Acetamiprid Accumulates in Different Amounts in Murine Brain Regions

    PubMed Central

    Terayama, Hayato; Endo, Hitoshi; Tsukamoto, Hideo; Matsumoto, Koichi; Umezu, Mai; Kanazawa, Teruhisa; Ito, Masatoshi; Sato, Tadayuki; Naito, Munekazu; Kawakami, Satoshi; Fujino, Yasuhiro; Tatemichi, Masayuki; Sakabe, Kou

    2016-01-01

    Neonicotinoids such as acetamiprid (ACE) belong to a new and widely used single class of pesticides. Neonicotinoids mimic the chemical structure of nicotine and share agonist activity with the nicotine acetylcholine receptor (nAchR). Neonicotinoids are widely considered to be safe in humans; however, they have recently been implicated in a number of human health disorders. A wide range of musculoskeletal and neuromuscular disorders associated with high doses of neonicotinoids administered to animals have also been reported. Consequently, we used a mouse model to investigate the response of the central nervous system to ACE treatment. Our results show that exposure to ACE-containing water for three or seven days (decuple and centuple of no observable adverse effect level (NOAEL)/day) caused a decrease in body weight in 10-week old A/JJmsSlc (A/J) mice. However, the treatments did not affect brain histology or expression of CD34. ACE concentrations were significantly higher in the midbrain of ACE-treated mice than that of the normal and vehicle groups. Expression levels of α7, α4, and β2 nAChRs were found to be low in the olfactory bulb and midbrain of normal mice. Furthermore, in the experimental group (centuple ACE-containing water for seven days), β2 nAChR expression decreased in many brain regions. Information regarding the amount of accumulated ACE and expression levels of the acetylcholine receptor in each region of the brain is important for understanding any clinical symptoms that may be associated with ACE exposure. PMID:27669271

  10. Acetamiprid Accumulates in Different Amounts in Murine Brain Regions.

    PubMed

    Terayama, Hayato; Endo, Hitoshi; Tsukamoto, Hideo; Matsumoto, Koichi; Umezu, Mai; Kanazawa, Teruhisa; Ito, Masatoshi; Sato, Tadayuki; Naito, Munekazu; Kawakami, Satoshi; Fujino, Yasuhiro; Tatemichi, Masayuki; Sakabe, Kou

    2016-09-22

    Neonicotinoids such as acetamiprid (ACE) belong to a new and widely used single class of pesticides. Neonicotinoids mimic the chemical structure of nicotine and share agonist activity with the nicotine acetylcholine receptor (nAchR). Neonicotinoids are widely considered to be safe in humans; however, they have recently been implicated in a number of human health disorders. A wide range of musculoskeletal and neuromuscular disorders associated with high doses of neonicotinoids administered to animals have also been reported. Consequently, we used a mouse model to investigate the response of the central nervous system to ACE treatment. Our results show that exposure to ACE-containing water for three or seven days (decuple and centuple of no observable adverse effect level (NOAEL)/day) caused a decrease in body weight in 10-week old A/JJmsSlc (A/J) mice. However, the treatments did not affect brain histology or expression of CD34. ACE concentrations were significantly higher in the midbrain of ACE-treated mice than that of the normal and vehicle groups. Expression levels of α7, α4, and β2 nAChRs were found to be low in the olfactory bulb and midbrain of normal mice. Furthermore, in the experimental group (centuple ACE-containing water for seven days), β2 nAChR expression decreased in many brain regions. Information regarding the amount of accumulated ACE and expression levels of the acetylcholine receptor in each region of the brain is important for understanding any clinical symptoms that may be associated with ACE exposure.

  11. Uncertainty in accounting for carbon accumulation following forest harvesting

    NASA Astrophysics Data System (ADS)

    Lilly, P.; Yanai, R. D.; Arthur, M. A.; Bae, K.; Hamburg, S.; Levine, C. R.; Vadeboncoeur, M. A.

    2014-12-01

    Tree biomass and forest soils are both difficult to quantify with confidence, for different reasons. Forest biomass is estimated non-destructively using allometric equations, often from other sites; these equations are difficult to validate. Forest soils are destructively sampled, resulting in little measurement error at a point, but with large sampling error in het