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Sample records for naturally occurring radionuclide

  1. Naturally occurring radionuclides in the ground water of southeastern Pennsylvania

    USGS Publications Warehouse

    Sloto, Ronald A.

    2000-01-01

    Naturally occurring radionuclides in the ground water of southeastern Pennsylvania may pose a health hazard to some residents, especially those drinking water from wells drilled in the Chickies Quartzite. Water from 46 percent of wells sampled in the Chickies Quartzite and 7 percent of wells sampled in other geologic formations exceeded the U.S. Environmental Protection Agency (USEPA) maximum contaminant level (MCL) for total radium. Radon-222 may pose a health problem for homeowners by contributing to indoor air radon-222 levels. The radon-222 activity of water from 89 percent of sampled wells exceeded 300 pCi/L (picocuries per liter), the proposed USEPA MCL, and water from 16 percent of sampled wells exceeded 4,000 pCi/L. Uranium does not appear to be present in elevated concentrations in ground water in southeastern Pennsylvania.

  2. Committed effective dose from naturally occuring radionuclides in shellfish

    NASA Astrophysics Data System (ADS)

    Khandaker, Mayeen Uddin; Wahib, Norfadira Binti; Amin, Yusoff Mohd.; Bradley, D. A.

    2013-07-01

    Recognizing their importance in the average Malaysian daily diet, the radioactivity concentrations in mollusc- and crustacean-based food have been determined for key naturally occuring radionuclides. Fresh samples collected from various maritime locations around peninsular Malaysia have been processed using standard procedures; the radionuclide concentrations being determined using an HPGe γ-ray spectrometer. For molluscs, assuming secular equilibrium, the range of activities of 238U (226Ra), 232Th (228Ra) and 40K were found to be 3.28±0.35 to 5.34±0.52, 1.20±0.21 to 2.44±0.21 and 118±6 to 281±14 Bq kg-1 dry weight, respectively. The respective values for crustaceans were 3.02±0.57 to 4.70±0.52, 1.38±0.21 to 2.40±0.35 and 216±11 to 316±15 Bq kg-1. The estimated average daily intake of radioactivity from consumption of molluscs are 0.37 Bq kg-1 for 238U (226Ra), 0.16 Bq kg-1 for 232Th (228Ra) and 18 Bq kg-1 for 40K; the respective daily intake values from crustaceans are 0.36 Bq kg-1, 0.16 Bq kg-1 and 23 Bq kg-1. Associated annual committed effective doses from molluscs are estimated to be in the range 21.3 to 34.7 μSv for 226Ra, 19.3 to 39.1 μSv for 228Ra and 17.0 to 40.4 μSv for 40K. For crustaceans, the respective dose ranges are 19.6 to 30.5 μSv, 22.0 to 38.4 μSv and 31.1 to 45.5 μSv, being some several times world average values.

  3. Measuring and Modeling Naturally Occurring Radioactive Material: Interpreting the Relationship Between the Natural Radionuclides Present

    SciTech Connect

    Lombardo, A.J.; Mucha, A.F.

    2008-07-01

    The regulatory release of sites and facilities (property) for restricted or unrestricted use has evolved beyond prescribed levels to model-derived dose and risk based limits. Dose models for deriving corresponding soil and structure radionuclide concentration guidelines are necessarily simplified representations of complex processes. A conceptual site model is often developed to present a reasonable and somewhat conservative representation of the physical and chemical properties of the impacted material. Dose modeling software is then used to estimate resulting dose and/or radionuclide specific acceptance criteria (activity concentrations). When the source term includes any or all of the uranium, thorium or actinium natural decay series radionuclides the interpretation of the relationship between the individual radionuclides of the series is critical to a technically correct and complete assessment of risk and/or derivation of radionuclide specific acceptance criteria. Unlike man-made radionuclides, modeling and measuring naturally occurring radioactive material (NORM) and technologically enhanced NORM (TENORM) source terms involves the interpretation of the relationship between the radionuclide present, e.g., secular equilibrium, enrichment, depletion or transient equilibrium. Isotopes of uranium, radium, and thorium occur in all three natural decay series. Each of the three series also produces a radon gas isotope as one of its progeny. In nature, the radionuclides in the three natural decay series are in a state that is approaching or has achieved secular equilibrium, in which the activities of all radionuclides within each series are nearly equal. However, ores containing the three natural decay series may begin in approximate secular equilibrium, but after processing, equilibrium may be broken and certain elements (and the radioactive isotopes of that element) may be concentrated or removed. Where the original ore may have contained one long chain of natural

  4. Activity measurements of technically enhanced naturally occurring radionuclides (TENORM) in phosphogypsum.

    PubMed

    Luca, A; Margineanu, R; Sahagia, M; Wätjen, A C

    2009-05-01

    Phosphogypsum is a by-product of the phosphoric acid based fertilizer industry; it can be used in agriculture and to make building materials. Phosphogypsum is radioactive due to the presence of technically enhanced naturally occurring radionuclides (TENORM) and its environmental impact is a major concern of the public authorities. The Radionuclide Metrology Laboratory from IFIN-HH participated at the IAEA-CU-2007-06-CCRI(II)-S5 Supplementary Comparison for the Determination of TENORM in phosphogypsum. The measurement procedures and the discussion of results and problems encountered are presented.

  5. Determination of naturally occurring radionuclides in soil samples of Ayranci, Turkey

    NASA Astrophysics Data System (ADS)

    Agar, Osman; Eke, Canel; Boztosun, Ismail; Emin Korkmaz, M.

    2015-04-01

    The specific activity, radiation hazard index and the annual effective dose of the naturally occurring radioactive elements (238U, 232Th and 40K) were determined in soil samples collected from 12 different locations in Ayranci region by using a NaI(Tl) gamma-ray spectrometer. The measured activity concentrations of the natural radionuclides in studied soil samples were compared with the corresponding results of different countries and the internationally reported values. From the analysis, it is found that these materials may be safely used as construction materials and do not pose significant radiation hazards.

  6. Enrichment and particle size dependence of polonium and other naturally occurring radionuclides in coal ash.

    PubMed

    Sahu, S K; Tiwari, M; Bhangare, R C; Pandit, G G

    2014-12-01

    Coal fired thermal power contributes 70% of power in India. Coal fired power generation results in huge amounts of fly ash and bottom ash of varying properties. Coal, which contains the naturally occurring radionuclides, on burning results in enrichment of these radionuclides in the ashes. In the present study, coal, bottom ash and fly ash samples collected from six coal-fired power plants in India were measured for (210)Po using alpha spectrometry and for natural U, (226)Ra, (232)Th and (40)K by an HPGe γ-ray spectrometer. (210)Po in fly ash ranged from 25.7 to 70 Bq/kg with a mean value of 40.5 Bq/kg. The range and mean activities of (238)U, (226)Ra, (232)Th, (40)K in fly ash were 38.5-101 (78.1), 60-105.7 (79), 20-125 (61.7) and 43.6-200 (100) Bq/kg respectively. Fly ash and bottom ash contains two to five times more natural radionuclides than feed coal. The results were compared with the available data from earlier studies in other countries. The effect of particle size on enrichment factor of the nuclides in fly ash was studied. (210)Po showed the largest size dependence with its concentration favoring the smaller particle size while (232)Th showed least size dependence. (238)U and (226)Ra showed behavior intermediate to that of (210)Po and (232)Th. Also the correlation between sulfur content of the feed coal and activity of (210)Po was investigated. Increased sulfur content in feed coal enhanced enrichment of (210)Po in ash. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Anthropogenic and naturally occurring radionuclide content in near surface air in Cáceres (Spain).

    PubMed

    Baeza, Antonio; Rodríguez-Perulero, Antonio; Guillén, Javier

    2016-12-01

    The anthropogenic ((137)Cs, (90)Sr, (239+240)Pu and (241)Am) and naturally occurring radionuclide ((40)K, (234,238)U, (228,230,232)Th, (226)Ra and (210)Pb) content in near surface air present seasonal variations related to natural processes, such as soil erosion, resuspension of fine particles of soil and radon exhalation from soil ((210)Pb). The objective is to analyze seasonal variations of their concentrations and compare with radiological events (Fukushima fallout and wild fire) in a location without any known source of anthropogenic radionuclides. The (210)Pb, (40)K, and (137)Cs presented annual variations, with maximum activity levels in summer. Solar radiation and rainfall were correlated with (210)Pb and (40)K. The (234,238)U, (228,230,232)Th, (226)Ra, (137)Cs and (90)Sr presented positive correlation with monthly mean values of temperature. The ratio (90)Sr/(137)Cs was within the range of those reported for soils in Spain. Finally, the maximal effective dose rate was estimated to be 37 and 88 μSv/y for infants and adults, respectively, well below 1 mSv/y reference level. The main contributor to effective dose was (210)Pb, about 92%, followed by: (210)Pb ≫ (228,230,232)Th > (226)Ra, (234,238)U > (7)Be, (239+240)Pu > (40)K, (90)Sr > (137)Cs > (22)Na.

  8. SUPPLEMENTARY COMPARISON Technically enhanced naturally occurring radionuclides (TENORM) in phosphogypsum: Comparison CCRI(II)-S5

    NASA Astrophysics Data System (ADS)

    Shakhashiro, A.; Sansone, U.; Wershofen, H.; Bollhöfer, A.; Kim, C. K.; Kim, C. S.; Korun, M.; Moune, M.; Lee, S. H.; Tarjan, S.

    2010-01-01

    Within the frame of mutual cooperation between the IAEA and the BIPM, the Consultative Committee for Ionizing Radiation Section II—Measurement of Radionuclides accepted an IAEA-organized interlaboratory comparison in 2008 on the determination of technically enhanced naturally occurring radionuclides in phosphogypsum. The study was piloted by the Chemistry Unit at the IAEA's Laboratories in Seibersdorf (Austria). This report presents the methodology applied in conducting this comparison and the results. Activity results for Pb-210, Ra-226, Th-230, U-234, U-235 and U-238 were reported by three national metrology institutes (NMI) and five other expert laboratories or designated institutes. Four different approaches were used to calculate the nominal value of the reported results and associated uncertainties, and the results from each individual participant were evaluated and compared with this nominal reference value. The reported evaluation of the measurement results demonstrated agreement amongst the participating laboratories. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI Section II, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

  9. Analysis of naturally-occurring radionuclides in coal combustion fly ash, gypsum, and scrubber residue samples.

    PubMed

    Roper, Angela R; Stabin, Michael G; Delapp, Rossane C; Kosson, David S

    2013-03-01

    Coal combustion residues from coal-fired power plants can be advantageous for use in building and construction materials. These by-products contain trace quantities of naturally occurring radionuclides from the uranium and thorium series, as well as other naturally occurring radionuclides such as K. Analysis was performed on samples of coal fly ash, flue gas desulfurization, gypsum and scrubber sludges, fixated scrubber sludges, and waste water filter cakes sampled from multiple coal-fired power plants in the United States. The radioactive content of U and Th decay series nuclides was determined using gamma photopeaks from progeny Pb at 352 keV and Tl at 583 keV, respectively; K specific activities were determined using the 1,461 keV photopeak. The samples were hermetically sealed to allow for secular equilibrium between the radium parents and the radon and subsequent progeny. Samples were analyzed in a common geometry using two high purity germanium photon detectors with low energy detection capabilities. The specific activities (Bq kg) were compared to results from literature studies including different building materials and fly ash specific activities. Fly ash from bituminous and subbituminous coals had U specific activities varying from 30-217 Bq kg (mean + 1 s.d. 119 ± 45 Bq kg) and 72-209 Bq kg (115 ± 40 Bq kg), respectively; Th specific activities from 10-120 Bq kg (73 ± 26 Bq kg) and 53-110 Bq kg (81 ± 18 Bq kg), respectively; and K specific activities from 177 to 928 Bq kg (569 ± 184 Bq kg) and 87-303 Bq kg (171 ± 69 Bq kg), respectively. Gypsum samples had U, Th, and K specific activities approximately one order of magnitude less than measured for fly ash samples.

  10. Radiological impact of dietary intakes of naturally occurring radionuclides on Pakistani adults.

    PubMed

    Akhter, P; Rahman, K; Orfi, S D; Ahmad, N

    2007-02-01

    Daily dietary intakes of three naturally occurring long-lived radionuclides (232)Th, (238)U and (40)K were estimated for the adult population of Pakistan using neutron activation analysis (NAA), inductively coupled plasma mass spectrometry (ICP-MS) and atomic absorption spectrometry (AAS), respectively. The daily intakes of (232)Th ranged from 4 to 29 mBq, (238)U ranged from 17 to 82 mBq and (40)K ranged from 51 to 128 Bq. The geometric means of these intakes were 10 mBqd(-1) for (232)Th, 33 mBqd(-1) for (238)U and 78.5 Bqd(-1) for (40)K. The measured values give annual committed effective doses of 0.80, 0.53 and 178.75 microSvyr(-1) for (232)Th, (238)U and (40)K, respectively to Pakistani population. The net radiological impact of these radionuclides is 180.08 microSvyr(-1). This value gives cancer risk factor of 4.5 x 10(-4) and loss of life expectancy of 0.87 days only. Whereas ICRP cancer risk factor for general public is 2.5 x 10(-3) and total risk involve from the all natural radiation sources based on global average annual radiation dose of 2.4 mSvyr(-1) is 6.0 x 10(-3). The estimated cancer risk shows that probability of increase of cancer risk from daily Pakistani diet is only a minor fraction of ICRP values. Therefore, the diet does not pose any significant health hazard and is considered radiologically safe for human consumption.

  11. Review of research on impacts to biota of discharges of naturally occurring radionuclides in produced water to the marine environment.

    PubMed

    Hosseini, Ali; Brown, Justin E; Gwynn, Justin P; Dowdall, Mark

    2012-11-01

    Produced water has been described as the largest volume waste stream in the exploration and production process of oil and gas. It is accompanied by discharges of naturally occurring radionuclides raising concerns over the potential radiological impacts of produced water on marine biota. In the Northern European marine environment, radioactivity in produced water has received substantial attention owing to the OSPAR Radioactive Substances Strategy which aims at achieving 'concentrations in the environment near background values for naturally occurring radioactive substances'. This review provides an overview of published research on the impacts to biota from naturally occurring radionuclides discharged in produced water by the offshore oil and gas industry. In addition to summarising studies and data that deal directly with the issue of dose and effect, the review also considers studies related to the impact of added chemicals on the fate of discharged radionuclides. The review clearly illustrates that only a limited number of studies have investigated possible impacts on biota from naturally occurring radionuclides present in produced water. Hence, although these studies indicate that the risk to the environment from naturally occurring radionuclides discharged in produced water is negligible, the substantial uncertainties involved in the assessments of impact make it difficult to be conclusive. With regard to the complexity involved in the problem under consideration there is a pressing need to supplement existing data and acquire new knowledge. Finally, the present work identifies some knowledge gaps to indicate future research requirements. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. Investigation of the activity level and radiological impacts of naturally occurring radionuclides in blast furnace slag.

    PubMed

    Uğur, F A; Turhan, S; Sahan, H; Sahan, M; Gören, E; Gezer, F; Yeğingil, Z

    2013-01-01

    The activity level and possible radiological impacts of naturally occurring radionuclides on the health of workers and members of the public, as a result of utilisation of blast furnace slag (BFS) samples as a substitute for aggregate in road construction were investigated by using a gamma-ray spectrometer and potential exposure scenarios given in Radiation Protection 122. The mean activity concentrations of the (226)Ra, (232)Th and (40)K in BFS samples were found to be 152.4, 54.9 and 183.1 Bq kg(-1), respectively. These values are compared with typical values measured in BFS samples from the European Union countries, which are 270, 70 and 240 Bq kg(-1) for (226)Ra, (232)Th and (40)K, respectively. The values of radium equivalent activity index calculated for BFS samples were within the recommended safety limits. The highest total annual effective doses evaluated as 0.9 and 0.4 mSv y(-1) for members of the public and workers, respectively, were lower than the annual limit of 1 mSv y(-1).

  13. Naturally Occurring Radionuclides of Ash Produced by Coal Combustion. The Case of the Kardia Mine in Northern Greece

    SciTech Connect

    Fotakis, M.; Tsikritzis, L.; Tzimkas, N.; Kolovos, N.; Tsikritzi, R.

    2008-08-07

    West Macedonia Lignite Center (WMLC), located in Northwest Greece, releases into the atmosphere about 21,400 tons/year of fly ash through the stacks of four coal fired plants. The lignite ash contains naturally occurring radionuclides, which are deposited on the WMLC basin. This work investigates the natural radioactivity of twenty six ash samples, laboratory produced from combustion of lignite, which was sampled perpendicularly to the benches of the Kardia mine. The concentrations of radionuclides {sup 40}K, {sup 235}U, {sup 238}U, {sup 226}Ra, {sup 228}Ra and {sup 232}Th, were measured spectroscopically and found round one order of magnitude as high as those of lignite. Subsequently the Radionuclide Partitioning Coefficients of radionuclides were calculated and it was found that they are higher for {sup 232}Th, {sup 228}Ra and {sup 40}K, because the latter have closer affinity with the inorganic matrix of lignite. During combustion up to one third of the naturally occurring radioisotopes escape from the solid phase into the flue gases. With comparison to relative global data, the investigated ash has been found to have relatively high radioactivity, but the emissions of the WMLC radionuclides contribute only 0.03% to the mean annual absorbed dose.

  14. Association of naturally occurring radionuclides in sludges from Drinking Water Treatment Plants previously optimized for their removal.

    PubMed

    Baeza, A; Salas, A; Guillén, J; Muñoz-Serrano, A

    2014-02-01

    The raw water used in Drinking Water Treatment Plants (DWTPs) can present high values of naturally occurring radionuclides. In order to reduce this content, the routine working conditions of DWTPs were successfully modified. This meant that those radionuclides were accumulated in the sludges generated, whose radioactive content was frequently above the exemption levels. It therefore becomes necessary to assess the association of naturally occurring radionuclides in the sludges for their potential use as agricultural fertilizers. Two approaches were studied: (a) the effect of different sequential extraction methods applied to a selected sludge; and (b) the effect of the different contents of inorganic complexes dissolved in the input water on the composition of the sludges generated by two DWTPs with different origins of their input water. Uranium and radium were mainly associated with the carbonated and reducible fractions, while (210)Po and (228)Th were associated with the residual fraction. There were differences between the two speciation methods, but the order of bioavailable radionuclides was roughly the same: (226)Ra≈(234,238)U>(228)Th>(210)Po. The major inorganic complexes content, mainly carbonate, in the raw water affected the radionuclide association. The greater the carbonate content in the raw water, the greater was the association of uranium and radium with the carbonated and easily reducible fractions.

  15. Using Naturally Occurring Radionuclides To Determine Drinking Water Age in a Community Water System.

    PubMed

    Waples, James T; Bordewyk, Jason K; Knesting, Kristina M; Orlandini, Kent A

    2015-08-18

    Drinking water quality in a community water system is closely linked to the age of water from initial treatment to time of delivery. However, water age is difficult to measure with conventional chemical tracers; particularly in stagnant water, where the relationship between disinfectant decay, microbial growth, and water age is poorly understood. Using radionuclides that were naturally present in source water, we found that measured activity ratios of (90)Y/(90)Sr and (234)Th/(238)U in discrete drinking water samples of known age accurately estimated water age up to 9 days old (σest: ± 3.8 h, P < 0.0001, r(2) = 0.998, n = 11) and 25 days old (σest: ± 13.3 h, P < 0.0001, r(2) = 0.996, n = 12), respectively. Moreover, (90)Y-derived water ages in a community water system (6.8 × 10(4) m(3) d(-1) capacity) were generally consistent with water ages derived from an extended period simulation model. Radionuclides differ from conventional chemical tracers in that they are ubiquitous in distribution mains and connected premise plumbing. The ability to measure both water age and an analyte (e.g., chemical or microbe) in any water sample at any time allows for new insight into factors that control drinking water quality.

  16. Using naturally occurring radionuclides to determine drinking water age in a community water system

    DOE PAGES

    Waples, James T.; Bordewyk, Jason K.; Knesting, Kristina M.; ...

    2015-07-22

    Drinking water quality in a community water system is closely linked to the age of water from initial treatment to time of delivery. However, water age is difficult to measure with conventional chemical tracers; particularly in stagnant water, where the relationship between disinfectant decay, microbial growth, and water age is poorly understood. Using radionuclides that were naturally present in source water, we found that measured activity ratios of 90Y/90Sr and 234Th/238U in discrete drinking water samples of known age accurately estimated water age up to 9 days old (σest: ± 3.8 h, P < 0.0001, r2 = 0.998, n =more » 11) and 25 days old (σest: ± 13.3 h, P < 0.0001, r2 = 0.996, n = 12), respectively. Moreover, 90Y-derived water ages in a community water system (6.8 × 104 m3 d–1 capacity) were generally consistent with water ages derived from an extended period simulation model. Radionuclides differ from conventional chemical tracers in that they are ubiquitous in distribution mains and connected premise plumbing. The ability to measure both water age and an analyte (e.g., chemical or microbe) in any water sample at any time allows for new insight into factors that control drinking water quality.« less

  17. Uranium and noble gas isotopes to decipher naturally-occuring radionuclide release into aquifers

    NASA Astrophysics Data System (ADS)

    Méjean, Pauline; Pinti, Daniele Luigi; Ghaleb, Bassam; Larocque, Marie

    2017-04-01

    Previously unknown relationships between helium isotopes and 234U/238U activity ratios in granular and fractured aquifers of the St. Lawrence Lowlands, Canada might help to resolve the long-standing debate of internal vs. internal sources of natural radionuclides in aquifers. Indeed, radiogenic 4He found in groundwater more than what could be produced in situ during the residence time of water has often been related to basal fluxes entering the bottom of aquifers. Other views suggest that only small portions of accumulated radiogenic helium in aquifer rocks can be released at steady-state. Most of locally produced helium would be released episodically during thermo-tectonic events. Here we show that 4He is correlated with 234U/238U activity ratios in local aquifers of Ordovician age of the St. Lawrence Lowlands, Québec. Groundwater flow and aquifer geometry was largely modified during the last post-glacial episode as observed for most periglacial aquifers of North America. This relation suggests the occurrence of three water masses: 1) freshwater containing atmospheric helium and 234U/238U activity ratios close to the secular equilibrium, indicating local and very shallow recharge; 2) freshwater penetrating the ground, dissolving rocks, and releasing 234U/238U activity ratios slightly higher than the secular equilibrium and large amount of radiogenic helium, indicating that rocks still preserve a reservoir of helium; 3) post-glacial groundwater containing large amount of helium and 234U/238U out of the secular equilibrium, indicating a fossil water having modified its U and He content during water-rock interactions. The U-He relationship is not straightforward. We suggest that post-glacial rebound and increased fracturing has favored the opening of new cracks and increased the specific surface of aquifer rocks. Along these newly created surfaces, He is released by diffusion and 234U by alpha-recoil, increasing the content of these two radionuclides in the water

  18. Using naturally occurring radionuclides to determine drinking water age in a community water system

    SciTech Connect

    Waples, James T.; Bordewyk, Jason K.; Knesting, Kristina M.; Orlandini, Kent A.

    2015-07-22

    Drinking water quality in a community water system is closely linked to the age of water from initial treatment to time of delivery. However, water age is difficult to measure with conventional chemical tracers; particularly in stagnant water, where the relationship between disinfectant decay, microbial growth, and water age is poorly understood. Using radionuclides that were naturally present in source water, we found that measured activity ratios of 90Y/90Sr and 234Th/238U in discrete drinking water samples of known age accurately estimated water age up to 9 days old (σest: ± 3.8 h, P < 0.0001, r2 = 0.998, n = 11) and 25 days old (σest: ± 13.3 h, P < 0.0001, r2 = 0.996, n = 12), respectively. Moreover, 90Y-derived water ages in a community water system (6.8 × 104 m3 d–1 capacity) were generally consistent with water ages derived from an extended period simulation model. Radionuclides differ from conventional chemical tracers in that they are ubiquitous in distribution mains and connected premise plumbing. The ability to measure both water age and an analyte (e.g., chemical or microbe) in any water sample at any time allows for new insight into factors that control drinking water quality.

  19. Enrichment of naturally occurring radionuclides and trace elements in Yatagan and Yenikoy coal-fired thermal power plants, Turkey.

    PubMed

    Ozden, Banu; Guler, Erkan; Vaasma, Taavi; Horvath, Maria; Kiisk, Madis; Kovacs, Tibor

    2017-09-28

    Coal, residues and waste produced by the combustion of the coal contain naturally occurring radionuclides such as (238)U, (226)Ra, (210)Pb, (232)Th and (4) K and trace elements such as Cd, Cr, Pb, Ni and Zn. In this work, coal and its combustion residues collected from Yatagan and Yenikoy coal fired thermal power plants (CPPs) in Turkey were studied to determine the concentrations of natural radionuclides and trace elements, and their enrichments factors to better understand the radionuclide concentration processes within the combustion system. In addition, the utilization of coal fly ash as a secondary raw material in building industry was also studied in terms of radiological aspects. Fly ash samples were taken at different stages along the emission control system of the thermal power plants. Activity concentrations of naturally occurring radionuclides were determined with Canberra Broad Energy Germanium (BEGe) detector BE3830-P and ORTEC Soloist PIPS type semiconductor detector. The particle size distribution and trace elements contents were determined in various ash fractions by the laser scattering particle size distribution analyzer and inductively coupled plasma (ICP-OES). From the obtained data, natural radionuclides tend to condense on fly ash with and the activity concentrations increase as the temperature drop in CPPs. Measured (210)Pb and (210)Po concentration varied between 186 ± 20-1153 ± 44 Bq kg(-1), and 56 ± 5-1174 ± 45 Bq kg(-1), respectively. The highest (210)Pb and (210)Po activity concentrations were determined in fly ash taken from the temporary storage point as 1153 ± 44 Bq kg(-1) and 1174 ± 45 Bq kg(-1), respectively. There were significant differences in the activity concentrations of some natural radionuclide and trace elements (Pb and Zn) contents in ash fractions among the sampling point inside both of the plants (ANOVA, p < 0.001). Coal and ash sample analysis showed an increase activity concentration and enrichment

  20. Naturally occurring radionuclides in food and drinking water from a thorium-rich area.

    PubMed

    da Costa Lauria, Dejanira; Rochedo, Elaine R R; Godoy, Maria Luisa D P; Santos, Eliane E; Hacon, Sandra S

    2012-11-01

    This paper focuses on a survey of uranium and thorium decay chain radionuclides in food and drinking water from the thorium-rich (monazite-bearing) region of Buena, which is located in the state of Rio de Janeiro, Brazil. The radionuclide concentration values in the food and drinking water from Buena reached values higher than 100-fold the international reference values. The daily intake of radionuclides by the local population is similar to that of another high background radiation area in Brazil, but the intake is higher than that of residents from a normal background radiation area. Approximately 58 % of the food consumed by Buena inhabitants is produced locally. Based on that figure, locally produced food and the dilution of total radionuclides in the diet of residents caused by food importation are both highly relevant to a population's intake of radionuclides. The concentration values for (210)Pb and the radium isotopes in drinking water from Buena are among the highest values to be reported in the literature. (228)Ra is the most important radionuclide ingested with both food and water among the inhabitants of Buena.

  1. Occupational exposure due to naturally occurring radionuclide material in granite quarry industry.

    PubMed

    Ademola, J A

    2012-02-01

    The potential occupational exposure in granite quarry industry due to the presence of naturally occurring radioactive material (NORM) has been investigated. The activity concentrations of (40)K, (226)Ra and (232)Th were determined using gamma-ray spectroscopy method. The annual effective dose of workers through different exposure pathways was determined by model calculations. The total annual effective dose varied from 21.48 to 33.69 μSv y(-1). Inhalation dose contributes the highest to the total effective dose. The results obtained were much lower than the intervention exemption levels (1.0 mSv y(-1)) given in the International Commission on Radiological Protection Publication 82.

  2. Partitioning of naturally-occurring radionuclides (NORM) in Marcellus Shale produced fluids influenced by chemical matrix†

    PubMed Central

    Nelson, Andrew W.; Johns, Adam J.; Eitrheim, Eric S.; Knight, Andrew W.; Basile, Madeline; Bettis, E. Arthur; Schultz, Michael. K.; Forbes, Tori Z.

    2017-01-01

    Naturally-occurring radioactive materials (NORM) associated with unconventional drilling produced fluids from the Marcellus Shale have raised environmental concerns. However, few investigations into the fundamental chemistry of NORM in Marcellus Shale produced fluids have been performed. Thus, we performed radiochemical experiments with Marcellus Shale produced fluids to understand the partitioning behavior of major radioelements of environmental health concern (uranium (U), thorium (Th), radium (Ra), lead (Pb), and polonium (Po)). We applied a novel radiotracer, 203Pb, to understand the behavior of trace-levels of 210Pb in these fluids. Ultrafiltration experiments indicated U, Th, and Po are particle reactive in Marcellus Shale produced fluids and Ra and Pb are soluble. Sediment partitioning experiments revealed that >99% of Ra does not adsorb to sediments in the presence of Marcellus Shale produced fluids. Further experiments indicated that although Ra adsorption is related to ionic strength, the concentrations of heavier alkaline earth metals (Ba, Sr) are stronger predictors of Ra solubility. PMID:26952871

  3. Partitioning of naturally-occurring radionuclides (NORM) in Marcellus Shale produced fluids influenced by chemical matrix.

    PubMed

    Nelson, Andrew W; Johns, Adam J; Eitrheim, Eric S; Knight, Andrew W; Basile, Madeline; Bettis, E Arthur; Schultz, Michael K; Forbes, Tori Z

    2016-04-01

    Naturally-occurring radioactive materials (NORM) associated with unconventional drilling produced fluids from the Marcellus Shale have raised environmental concerns. However, few investigations into the fundamental chemistry of NORM in Marcellus Shale produced fluids have been performed. Thus, we performed radiochemical experiments with Marcellus Shale produced fluids to understand the partitioning behavior of major radioelements of environmental health concern (uranium (U), thorium (Th), radium (Ra), lead (Pb), and polonium (Po)). We applied a novel radiotracer, (203)Pb, to understand the behavior of trace-levels of (210)Pb in these fluids. Ultrafiltration experiments indicated U, Th, and Po are particle reactive in Marcellus Shale produced fluids and Ra and Pb are soluble. Sediment partitioning experiments revealed that >99% of Ra does not adsorb to sediments in the presence of Marcellus Shale produced fluids. Further experiments indicated that although Ra adsorption is related to ionic strength, the concentrations of heavier alkaline earth metals (Ba, Sr) are stronger predictors of Ra solubility.

  4. Naturally-Occurring Radionuclides In Drinking Water From Surface And Groundwater Reservoirs

    SciTech Connect

    Carvalho, F. P.; Madruga, M. J.; Oliveira, J. M.; Lopes, I.; Ferrador, G.; Sequeira, M. M.

    2008-08-07

    Radioactivity in water for human consumption is under closer scrutiny than ever before and many countries adopted guideline values based on total alpha and total beta activity measurements. Although most waters from surface circulation meet these guidelines, it is frequently found that groundwater exceed guideline values. Results of water analyses by alpha spectrometry clarified that the main radionuclides present are from the uranium decay series, such as uranium isotopes, radium ({sup 226}Ra), radon ({sup 222}Rn), and also {sup 210}Pb and {sup 210}Po. Occasionally, groundwater displayed {sup 226}Ra concentrations higher than 1 Bq L{sup -1} and {sup 222}Rn concentrations above 1000 Bq L{sup -1}. Nevertheless, lack of conformity of these waters with guidelines adopted, generally, is not due to anthropogenic inputs.

  5. Measurement of naturally occurring radionuclides in geothermal samples and assessment of radiological risks and radiation doses.

    PubMed

    Parmaksiz, A

    2013-12-01

    The analysis of (226)Ra, (232)Th and (40)K radionuclides has been carried out in geothermal water and residue samples collected from six wells of geothermal power plant and disposal site, using gamma-spectrometry system equipped with a high-purity germanium detector. The activity concentrations of nine geothermal water samples were found to be lower than minimum detectable activity (MDA) values. The activity concentration of the residue samples ranged from 40 ± 4 to 2694 ± 85 Bq kg(-1) for (226)Ra, 33 ± 4 to 2388 ± 85 Bq kg(-1) for (232)Th, and MDA value to 967 ± 30 Bq kg(-1) for (40)K. In the study, some radiological indexes were examined and found to be higher than the reference values for majority of the residue samples. The annual effective doses arising from some residue samples were calculated to be higher than the permitted dose rate for the public, i.e. 1 mSv y(-1).

  6. Naturally occurring radionuclides and rare earth elements in weathered Japanese soil samples

    NASA Astrophysics Data System (ADS)

    Sahoo, Sarata; Hosoda, Masahiro; Prasad, Ganesh; Takahashi, Hiroyuki; Sorimachi, Atsuyuki; Ishikawa, Tetsuo; Tokonami, Shinji; Uchida, Shigeo

    2013-08-01

    The activity concentrations of 226Ra and 228Ac in weathered Japanese soils from two selected prefectures have been measured using a γ-ray spectroscopy system with high purity germanium detector. The uranium, thorium, and rare earth elements (REEs) concentrations were determined from the same soil samples using inductively coupled plasma mass spectrometry (ICP-MS). For example, granitic rocks contain higher amounts of U, Th, and light REEs compared to other igneous rocks such as basalt and andesites. Therefore, it is necessary to understand the interaction between REEs and nature of soils since soils are complex heterogeneous mixture of organic and inorganic solids, water, and gases. In this paper, we will discuss about distribution pattern of 238U and 232Th along with REEs in soil samples of weathered acid rock (granite) collected from two prefectures of Japan: Hiroshima and Miyagi.

  7. Baseline data of naturally occurring radionuclides in some native vegetables and fruits in Southern Thailand.

    PubMed

    Kranrod, C; Chanyotha, S; Pornnumpa, C; Kritsananuwat, R; Sriploy, P

    2015-11-01

    The aim of this study was to provide the baseline data information on natural radioactivities in vegetables and fruits produced and consumed locally in the areas of potential nuclear power plant sites in Thailand. Four provinces (Prajuab-Kirikhan, Chumphon, Surat-Thani and Nakhon-Si-thammarat) were selected for collection of native vegetables and fruits samples, together with their corresponding soils. The activities of (226)Ra, (228)Ra, (40)K and (210)Po were determined in all these samples. The obtained results for (226)Ra, (228)Ra, (40)K and (210)Po for all vegetable and fruit samples were in the range of 1-34, 1-108, 32-4392 and 0.2-47 Bq kg(-1), respectively, which were much lower than those obtained for their corresponding soils. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Removal naturally occurring radionuclides from drinking water using a filter specifically designed for Drinking Water Treatment Plants.

    PubMed

    Baeza, A; Salas, A; Guillén, J; Muñoz-Serrano, A; Ontalba-Salamanca, M Á; Jiménez-Ramos, M C

    2017-01-01

    The occurrence of naturally occurring radionuclides in drinking water can pose health hazards in some populations, especially taking into account that routine procedures in Drinking Water Treatment Plants (DWTPs) are normally unable to remove them efficiently from drinking water. In fact, these procedures are practically transparent to them, and in particular to radium. In this paper, the characterization and capabilities of a patented filter designed to remove radium from drinking water with high efficiency is described. This filter is based on a sandwich structure of silica and green sand, with a natural high content manganese oxide. Both sands are authorized by Spanish authorities to be used in Drinking Water Treatment Plants. The Mn distribution in the green sand was found to be homogenous, thus providing a great number of adsorption sites for radium. Kinetic studies showed that the (226)Ra adsorption on green sand was influenced by the content of major cations solved in the treated water, but the saturation level, about 96-99%, was not affected by it. The physico-chemical parameters of the treated water were unaltered by the filter. The efficiency of the filter for the removal of (226)Ra remained unchanged with large water volumes passed through it, proving its potential use in DWTP. This filter was also able to remove initially the uranium content due to the presence of Fe2O3 particles in it, although it is saturated faster than radium.

  9. Natural Radionuclides in Ground Water.

    ERIC Educational Resources Information Center

    Davis, Stanley N.

    1988-01-01

    Described are the natural trace radionuclides in ground water. Indicates the geologic origin of these radionuclides. Discusses the importance of these radionuclides. Suggests future uses of a number of additional radionuclides. (CW)

  10. Natural Radionuclides in Ground Water.

    ERIC Educational Resources Information Center

    Davis, Stanley N.

    1988-01-01

    Described are the natural trace radionuclides in ground water. Indicates the geologic origin of these radionuclides. Discusses the importance of these radionuclides. Suggests future uses of a number of additional radionuclides. (CW)

  11. Distribution, enrichment and principal component analysis for possible sources of naturally occurring and anthropogenic radionuclides in the agricultural soil of Punjab state, India.

    PubMed

    Kumar, Ajay; Joshi, Vikram M; Mishra, Manish K; Karpe, Rupali; Rout, Sabyasachi; Narayanan, Usha; Tripathi, Raj M; Singh, Jaspal; Kumar, Sanjeev; Hegde, Ashok G; Kushwaha, Hari S

    2012-06-01

    Enrichment factor (EF) of elements including geo-accumulation indices for soil quality and principal component analysis (PCA) were used to identify the contributions of the origin of sources in the studied area. Results of (40)K, (137)Cs, (238)U and (232)Th including their decay series isotopes in the agricultural soil of Mansa and Bathinda districts in the state of Punjab were presented and discussed. The measured mean radioactivity concentrations for (238)U, (232)Th and (40)K in the agricultural soil of the studied area differed from nationwide average crustal abundances by 51, 17 and 43 %, respectively. The sequence of the EFs of radionuclides in soil from the greatest to the least was found to be (238)U > (40)K > (226)Ra > (137)Cs > (232)Th > (228)Ra. Even though the enrichment of naturally occurring radionuclides was found to be higher, they remained to be in I(geo) class of '0', indicating that the soil is uncontaminated with respect to these radionuclides. Among non-metals, N showed the highest EF and belonged to I(geo) class of '2', indicating that soil is moderately contaminated due to intrusion of fertiliser. The resulting data set of elemental contents in soil was also interpreted by PCA, which facilitates identification of the different groups of correlated elements. The levels of the (40)K, (238)U and (232)Th radionuclides showed a significant positive correlation with each other, suggesting a similar origin of their geochemical sources and identical behaviour during transport in the soil system.

  12. Comparison of long-term stability of containment systems for residues and wastes contaminated with naturally occurring radionuclides at an arid site and two humid sites

    SciTech Connect

    Winters, M.; Merry-Libby, P.; Hinchman, R.

    1985-01-01

    The long-term stability of near-surface containment systems designed for the management of radioactive wastes and residues contaminated with naturally occurring radionuclides are compared at the three different sites. The containment designs are: (1) a diked 8.9-m high mound, including a 3.2-m layered cap at a site (humid) near Lewiston, New York, (2) a 6.8-m-high mound, including a similar 3.2-m cap at a site (humid) near Oak Ridge, Tennessee, and (3) 4.8-m deep trenches with 3.0-m backfilled caps at a site (arid) near Hanford, Washington. Geological, hydrological, and biological factors affecting the long-term (1000-year) integrity of the containment systems at each site are examined, including: erosion, flooding, drought, wildfire, slope and cover failure, plant root penetration, burrowing animals, other soil-forming processes, and land-use changes. For the containment designs evaluated, releases of radon-222 at the arid site are predicted to be several orders of magnitude higher than at the two humid sites - upon initial burial and at 1000 years (after severe erosion). Transfer of wastes containing naturally occurring radionuclides from a humid to an arid environment offers little or no advantage relative to long-term stability of the containment system and has a definite disadvantage in terms of gaseous radioactive releases. 26 references, 3 figures, 4 tables.

  13. Naturally Occurring Radioactive Materials (NORM)

    SciTech Connect

    Gray, P.

    1997-02-01

    This paper discusses the broad problems presented by Naturally Occuring Radioactive Materials (NORM). Technologically Enhanced naturally occuring radioactive material includes any radionuclides whose physical, chemical, radiological properties or radionuclide concentration have been altered from their natural state. With regard to NORM in particular, radioactive contamination is radioactive material in an undesired location. This is a concern in a range of industries: petroleum; uranium mining; phosphorus and phosphates; fertilizers; fossil fuels; forestry products; water treatment; metal mining and processing; geothermal energy. The author discusses in more detail the problem in the petroleum industry, including the isotopes of concern, the hazards they present, the contamination which they cause, ways to dispose of contaminated materials, and regulatory issues. He points out there are three key programs to reduce legal exposure and problems due to these contaminants: waste minimization; NORM assesment (surveys); NORM compliance (training).

  14. Naturally occurring chemical carcinogens

    USDA-ARS?s Scientific Manuscript database

    Natural products are chemicals found in nature which have unique pharmacological effects. Humans are exposed to many of these bioactive naturally occurring chemicals via the air breathed, the water drunk and the food eaten. Exposure also occurs in clinical settings. Naturally occurring chemicals ...

  15. Radiological hazards due to naturally occurring radionuclides in the selected building materials used for the construction of dwellings in four districts of the Punjab Province, Pakistan.

    PubMed

    Rahman, S U; Rafique, M; Jabbar, A; Matiullah

    2013-03-01

    This paper presents the finding of a study undertaken to determine the naturally occurring radionuclides present in commonly used building materials for dwellings and workplaces in four districts of the Punjab Province, Pakistan. The concentrations of (226)Ra, (232)Th and (40)K were measured by using gamma-ray spectroscopy. A total of 80 samples of building materials were collected from various manufacturers and suppliers of the studied area. The specific activities of (226)Ra, (232)Th and (40)K were measured in building samples, and results ranged from minimum values of 9 ± 1, 9 ± 2 and 27 ± 8 Bq kg(-1) to maximum values of 106 ± 5, 133 ± 5 and 914 ± 21 Bq kg(-1) with mean values of 42 ± 3, 48 ± 3 and 376 ± 16 Bq kg(-1), respectively. From the measured activity concentrations, equivalent radium (Ra(eq)), terrestrial absorbed dose rate, annual effective dose as well as external and internal hazard indices were calculated and found to range from 52 ± 7 to 274 ± 15 Bq kg(-1), 23 ± 3 to 130 6 nGy h(-1), 0.15 ± 0.02 to 0.80 ± 0.03 mSv, 0.14 ± 0.02 to 0.75 ± 0.04 and 0.2 ± 0.02 to 0.98 ± 0.05, respectively. These results were comparable to the results of similar studies undertaken locally and in other countries. The samples considered were safe for use in construction of dwellings in the study area and do not pose any significant source of radiation hazard.

  16. A pilot study to assess the feasibility of using naturally-occurring radionuclides as mass balance tracers to estimate soil ingestion.

    PubMed

    Doyle, J R; White, P A; Blais, J M

    2012-09-01

    The relatively few soil ingestion studies that have been conducted to date to support soil ingestion rate values used for contaminated site human health risk assessments (HHRAs) typically have measured mass balance elemental tracers (e.g., Al, Si, Ba, Ce, Mn, Ti, V, Zr), found in soil to estimate soil ingestion. This pilot study, involving a canine subject fed a known amount of tracer on a daily basis, assessed the use of alternative mass balance tracers, specifically naturally occurring radionuclides of the (238)U and (232)Th decay series, to estimate soil ingestion. A novel method of estimating soil ingestion via difference in isotopic ratios between the two decay series in food and soil was also assessed. The results of the study showed that the mean (214)Pb and (212)Pb activities measured in fecal samples were greater than what was contained in the soil inoculant, suggesting that the tracers were not being significantly absorbed in the GI tract. The mean daily soil ingestion rates, calculated after subtracting the contribution of tracers in the soil inoculant, were 3.9 g d(-1) (standard deviation 3.6 g d(-1)) for the isotope tracers, and 1.9 g(-1) (standard deviation 2.1 g d(-1)) for the 3 most reliable elemental tracers. The differences were not statistically significant and further evaluation of isotopic tracers for soil ingestion studies is warranted. Similarly, soil ingestion estimates calculated using the Isotope Ratio Method were not significantly different than when calculated using (212)Pb; however, the Isotope Ratio Method was observed to positively bias the soil ingestion estimates by approximately 50%. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Naturally occurring insecticides.

    PubMed Central

    Soloway, S B

    1976-01-01

    Naturally occurring insecticides are abundant and varied in their effects, though but a few are articles of commerce. Even for these, pyrethrum, nicotine, rotenone, hellebore, ryania, and sabadilla, there is a paucity of information on mammalian toxicology and environmental effects. In general, these materials are characterized favorably by low acute toxicity and ready dissipation in nature. Unfavorable aspects of natural insecticides are the contained mixture of active and inactive components and the low active ingredient content on a crop yield basis pointing to a high unit cost. Natural insecticides can serve additionally as leads to unnatural mimics, of which the commercially successful synthetic pyrethroids are prime examples. The chemical nature, relationship of insecticidal activity to chemical structure, occurrence, production, and utilization, registered uses, metabolism, and insect and mammalian toxicity are reviewed. PMID:789058

  18. "Naturally occurring asbestos

    NASA Astrophysics Data System (ADS)

    Cagnard, F.; Lahondère, D.; Blein, O.; Lahfid, A.; Wille, G.

    2012-04-01

    The term asbestos refers to six silicate minerals from amphibole and serpentine groups. By definition, it consists in bundles of thin and flexible long fibers, with high-tensile strength, and chemical and heat resistance. In contrast to asbestos found within commercial products and mining, the specific term ''naturally occurring asbestos'' (NOA) refers to asbestiform minerals occurring within rocks or soils that can be released by human activities or weathering processes. The fact that the exposure to asbestos is related to lung pathologies is now widely demonstrated (e.g. asbestosis, mesothelioma and lung cancer). However, if health risks associated with exposure to NOA exist, they are not yet well documented. The crystallization of natural asbestos occurs in specific Mg-rich lithologies associated with peculiar structural and metamorphic conditions. By recognizing and combining such specific geologic criteria, the presence or the absence of asbestos in bedrock terrains can be reasonably predicted and maps of NOA hazard can be drawn. We present here new results of geological mapping and petrological study concerning the evaluation of the NOA hazard in the Alps and Corsica, in France. The three folds approach consists in (1) a determination of lithologies with potential NOA from a bibliographic compilation and extraction of target zones from a geological geodatabase (2) a geological mapping of the target zones followed by a petrological characterization of sampled asbestiform minerals in the laboratory (optical microscopy, TEM, SEM, and Raman spectroscopy technics), and (3) the drawing of the final map of NOA hazard, at regional-scale. Occurrence criteria can be retained as follows: 1. NOA are abundant in the internal zones of the Alps and Corsica, especially within ophiolitic complexes. Natural asbestos are mostly concentrated within ultramafic rocks but can also occur within basic lithologies such as Mg-metagabbros, metabasalts and meta-pillow-lavas, 2. Asbestos

  19. 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.

  20. Naturally Occurring Food Toxins

    PubMed Central

    Dolan, Laurie C.; Matulka, Ray A.; Burdock, George A.

    2010-01-01

    Although many foods contain toxins as a naturally-occurring constituent or, are formed as the result of handling or processing, the incidence of adverse reactions to food is relatively low. The low incidence of adverse effects is the result of some pragmatic solutions by the US Food and Drug Administration (FDA) and other regulatory agencies through the creative use of specifications, action levels, tolerances, warning labels and prohibitions. Manufacturers have also played a role by setting limits on certain substances and developing mitigation procedures for process-induced toxins. Regardless of measures taken by regulators and food producers to protect consumers from natural food toxins, consumption of small levels of these materials is unavoidable. Although the risk for toxicity due to consumption of food toxins is fairly low, there is always the possibility of toxicity due to contamination, overconsumption, allergy or an unpredictable idiosyncratic response. The purpose of this review is to provide a toxicological and regulatory overview of some of the toxins present in some commonly consumed foods, and where possible, discuss the steps that have been taken to reduce consumer exposure, many of which are possible because of the unique process of food regulation in the United States. PMID:22069686

  1. Naturally occurring food toxins.

    PubMed

    Dolan, Laurie C; Matulka, Ray A; Burdock, George A

    2010-09-01

    Although many foods contain toxins as a naturally-occurring constituent or, are formed as the result of handling or processing, the incidence of adverse reactions to food is relatively low. The low incidence of adverse effects is the result of some pragmatic solutions by the US Food and Drug Administration (FDA) and other regulatory agencies through the creative use of specifications, action levels, tolerances, warning labels and prohibitions. Manufacturers have also played a role by setting limits on certain substances and developing mitigation procedures for process-induced toxins. Regardless of measures taken by regulators and food producers to protect consumers from natural food toxins, consumption of small levels of these materials is unavoidable. Although the risk for toxicity due to consumption of food toxins is fairly low, there is always the possibility of toxicity due to contamination, overconsumption, allergy or an unpredictable idiosyncratic response. The purpose of this review is to provide a toxicological and regulatory overview of some of the toxins present in some commonly consumed foods, and where possible, discuss the steps that have been taken to reduce consumer exposure, many of which are possible because of the unique process of food regulation in the United States.

  2. [Evaluation of the partial contribution of naturally occurring radionuclides and nonradioactive chemically toxic elements in formation of biological effects within the Vicia cracca population inhabiting the area contaminated with uranium-radium production wastes in the Komi Republic].

    PubMed

    Evseeva, T I; Geras'kin, S A; Vakhrusheva, O M

    2014-01-01

    The site contaminated with uranium-radium production wastes in the Komi Republic was studied. The activity concentration of naturally occurring radionuclides (226Ra, 228Th, 238U, 230Th, 232Th, 210Po, and 210Pb), as well as concentrations of nonradioactive chemically toxic elements (Pb, Zn, Cu, As, V, Mo, Sr, Y, and Ba) in the soil samples from the experimental site is 10-183 times higher than reference levels. A chronic exposure to alpha-emitters and nonradioactive chemically toxic elements causes adverse effects in tufted vetch (Vacia cracca L.) both at the cellular (aberration of chromosomes) and population (decrease in the reproductive ability) levels. Radionuclides are the main contributors to the decrease in the reproductive capacity and an increase in the level of the cytogenetic damage in root tip cells of tufted vetch seedlings. As and Pb significantly influence the reproductive capacity of plants. Sr, Zn, Y and P modify the biological effects caused by exposure to radionuclides. Moreover, P and Zn reduce the adverse effects of radionuclides; however, Sr and Y enhance these effects.

  3. Illicit Trafficking of Natural Radionuclides

    SciTech Connect

    Friedrich, Steinhaeusler; Lyudmila, Zaitseva

    2008-08-07

    Natural radionuclides have been subject to trafficking worldwide, involving natural uranium ore (U 238), processed uranium (yellow cake), low enriched uranium (<20% U 235) or highly enriched uranium (>20% U 235), radium (Ra 226), polonium (Po 210), and natural thorium ore (Th 232). An important prerequisite to successful illicit trafficking activities is access to a suitable logistical infrastructure enabling an undercover shipment of radioactive materials and, in case of trafficking natural uranium or thorium ore, capable of transporting large volumes of material. Covert en route diversion of an authorised uranium transport, together with covert diversion of uranium concentrate from an operating or closed uranium mines or mills, are subject of case studies. Such cases, involving Israel, Iran, Pakistan and Libya, have been analyzed in terms of international actors involved and methods deployed. Using international incident data contained in the Database on Nuclear Smuggling, Theft and Orphan Radiation Sources (DSTO) and international experience gained from the fight against drug trafficking, a generic Trafficking Pathway Model (TPM) is developed for trafficking of natural radionuclides. The TPM covers the complete trafficking cycle, ranging from material diversion, covert material transport, material concealment, and all associated operational procedures. The model subdivides the trafficking cycle into five phases: (1) Material diversion by insider(s) or initiation by outsider(s); (2) Covert transport; (3) Material brokerage; (4) Material sale; (5) Material delivery. An Action Plan is recommended, addressing the strengthening of the national infrastructure for material protection and accounting, development of higher standards of good governance, and needs for improving the control system deployed by customs, border guards and security forces.

  4. Illicit Trafficking of Natural Radionuclides

    NASA Astrophysics Data System (ADS)

    Friedrich, Steinhäusler; Lyudmila, Zaitseva

    2008-08-01

    Natural radionuclides have been subject to trafficking worldwide, involving natural uranium ore (U 238), processed uranium (yellow cake), low enriched uranium (<20% U 235) or highly enriched uranium (>20% U 235), radium (Ra 226), polonium (Po 210), and natural thorium ore (Th 232). An important prerequisite to successful illicit trafficking activities is access to a suitable logistical infrastructure enabling an undercover shipment of radioactive materials and, in case of trafficking natural uranium or thorium ore, capable of transporting large volumes of material. Covert en route diversion of an authorised uranium transport, together with covert diversion of uranium concentrate from an operating or closed uranium mines or mills, are subject of case studies. Such cases, involving Israel, Iran, Pakistan and Libya, have been analyzed in terms of international actors involved and methods deployed. Using international incident data contained in the Database on Nuclear Smuggling, Theft and Orphan Radiation Sources (DSTO) and international experience gained from the fight against drug trafficking, a generic Trafficking Pathway Model (TPM) is developed for trafficking of natural radionuclides. The TPM covers the complete trafficking cycle, ranging from material diversion, covert material transport, material concealment, and all associated operational procedures. The model subdivides the trafficking cycle into five phases: (1) Material diversion by insider(s) or initiation by outsider(s); (2) Covert transport; (3) Material brokerage; (4) Material sale; (5) Material delivery. An Action Plan is recommended, addressing the strengthening of the national infrastructure for material protection and accounting, development of higher standards of good governance, and needs for improving the control system deployed by customs, border guards and security forces.

  5. Traces of natural radionuclides in animal food

    NASA Astrophysics Data System (ADS)

    Merli, Isabella Desan; da Silveira, Marcilei A. Guazzelli; Medina, Nilberto H.

    2014-11-01

    Naturally occurring radioactive materials are present everywhere, e.g., in soil, air, housing materials, food, etc. Therefore, human beings and animals receive internal exposure from radioactive elements inside their bodies through breathing and alimentation. Gamma radiation has enough energy to remove an electron from the atom and compromise the rearrangement of electrons in the search for a more stable configuration which can disturb molecule chemical bonding. Food ingestion is one of the most common forms of radioisotopes absorption. The goal of this work is the measurement of natural gamma radiation rates from natural radioisotopes present in animal food. To determine the concentration of natural radionuclides present in animal food gamma-ray spectrometry was applied. We have prepared animal food samples for poultry, fish, dogs, cats and cattle. The two highest total ingestion effective doses observed refers to a sample of mineral salt cattle, 95.3(15) μSv/year, rabbit chow, with a value of 48(5) μSv/year, and cattle mineral salt, with a value of 69(7) μSv/year, while the annual total dose value from terrestrial intake radionuclide is of the order of 290 μSv/year.

  6. Traces of natural radionuclides in animal food

    SciTech Connect

    Merli, Isabella Desan; Guazzelli da Silveira, Marcilei A.; Medina, Nilberto H.

    2014-11-11

    Naturally occurring radioactive materials are present everywhere, e.g., in soil, air, housing materials, food, etc. Therefore, human beings and animals receive internal exposure from radioactive elements inside their bodies through breathing and alimentation. Gamma radiation has enough energy to remove an electron from the atom and compromise the rearrangement of electrons in the search for a more stable configuration which can disturb molecule chemical bonding. Food ingestion is one of the most common forms of radioisotopes absorption. The goal of this work is the measurement of natural gamma radiation rates from natural radioisotopes present in animal food. To determine the concentration of natural radionuclides present in animal food gamma-ray spectrometry was applied. We have prepared animal food samples for poultry, fish, dogs, cats and cattle. The two highest total ingestion effective doses observed refers to a sample of mineral salt cattle, 95.3(15) μSv/year, rabbit chow, with a value of 48(5) μSv/year, and cattle mineral salt, with a value of 69(7) μSv/year, while the annual total dose value from terrestrial intake radionuclide is of the order of 290 μSv/year.

  7. Introduction to naturally occurring radioactive material

    SciTech Connect

    Egidi, P.

    1997-08-01

    Naturally occurring radioactive material (NORM) is everywhere; we are exposed to it every day. It is found in our bodies, the food we eat, the places where we live and work, and in products we use. We are also bathed in a sea of natural radiation coming from the sun and deep space. Living systems have adapted to these levels of radiation and radioactivity. But some industrial practices involving natural resources concentrate these radionuclides to a degree that they may pose risk to humans and the environment if they are not controlled. Other activities, such as flying at high altitudes, expose us to elevated levels of NORM. This session will concentrate on diffuse sources of technologically-enhanced (TE) NORM, which are generally large-volume, low-activity waste streams produced by industries such as mineral mining, ore benefication, production of phosphate Fertilizers, water treatment and purification, and oil and gas production. The majority of radionuclides in TENORM are found in the uranium and thorium decay chains. Radium and its subsequent decay products (radon) are the principal radionuclides used in characterizing the redistribution of TENORM in the environment by human activity. We will briefly review other radionuclides occurring in nature (potassium and rubidium) that contribute primarily to background doses. TENORM is found in many waste streams; for example, scrap metal, sludges, slags, fluids, and is being discovered in industries traditionally not thought of as affected by radionuclide contamination. Not only the forms and volumes, but the levels of radioactivity in TENORM vary. Current discussions about the validity of the linear no dose threshold theory are central to the TENORM issue. TENORM is not regulated by the Atomic Energy Act or other Federal regulations. Control and regulation of TENORM is not consistent from industry to industry nor from state to state. Proposed regulations are moving from concentration-based standards to dose

  8. Characterization of calculation of in-situ retardation factors of contaminant transport using naturally-radionuclides and rock/water interaction occurring U-Series disequilibria timescales. 1997 annual progress report

    SciTech Connect

    Roback, R.; Murrel, M.; Goldstein, S.; Ku, T.L.; Luo, S.

    1997-01-01

    'The research is directed toward a quantitative assessment of contaminant transport rates in fracture-rock systems using uranium-series radionuclides. Naturally occurring uranium-and thorium-series radioactive disequilibria will provide information on the rates of adsorption-desorption and transport of radioactive contaminants as well as on fluid transport and rock dissolution in a natural setting. This study will also provide an improved characterization of preferential flow and contaminant transport at the Idaho Environmental and Engineering Lab. (INEEL) site. To a lesser extent, the study will include rocks in the unsaturated zone. The authors will produce a realistic model of radionuclide migration under unsaturated and saturated field conditions at the INEEL site, taking into account the retardation processes involved in the rock/water interaction. The major tasks are to (1) determine the natural distribution of U, Th, Pa and Ra isotopes in rock minerals. sorbed phases on the rocks, and in fluids from both saturated and unsaturated zones at the site, and (2) study rock/water interaction processes using U/Th series disequilibrium and a statistical analysis-based model for the Geologic heterogeneity plays an important role in transporting contaminants in fractured rocks. Preferential flow paths in the fractured rocks act as a major pathway for transport of radioactive contaminants in groundwaters. The weathering/dissolution of rock by groundwater also influences contaminant mobility. Thus, it is important to understand the hydrogeologic features of the site and their impact on the migration of radioactive contaminants. In this regard, quantification of the rock weathering/dissolution rate and fluid residence time from the observed decay-series disequilibria will be valuable. By mapping the spatial distribution of the residence time of groundwater in fractured rocks, the subsurface preferential flow paths (with high rock permeability and short fluid residence

  9. Natural chelates for radionuclide decorporation

    DOEpatents

    Premuzic, E.T.

    1983-08-25

    This invention relates to the method and resulting chelates of desorbing a radionuclide selected from thorium, uranium, and plutonium containing cultures in a bioavailable form involving pseudomonas or other microorganisms. A preferred microorganism is Pseudomonas aeruginosa which forms multiple chelates with thorium in the range of molecular weight 1000 to 1000 and also forms chelates with uranium of molecular weight in the area of 100 to 1000 and 1000 to 2000.

  10. EVALUATING MONITORED NATURAL ATTENUATION FOR RADIONUCLIDE & ORGANIC CONTAMINATION IN GROUNDWATER (SALT LAKE CITY, UT)

    EPA Science Inventory

    Monitored Natural Attenuation (MNA) for radionuclides and inorganic contaminants is dependent on naturally occurring processes in the subsurface that act without human intervention to reduce the mass, toxicity, mobility, volume or concentration of contaminants. EPA is developing ...

  11. EVALUATING MONITORED NATURAL ATTENUATION FOR RADIONUCLIDE & ORGANIC CONTAMINATION IN GROUNDWATER (SALT LAKE CITY, UT)

    EPA Science Inventory

    Monitored Natural Attenuation (MNA) for radionuclides and inorganic contaminants is dependent on naturally occurring processes in the subsurface that act without human intervention to reduce the mass, toxicity, mobility, volume or concentration of contaminants. EPA is developing ...

  12. Reuse of Material Containing Natural Radionuclides - 12444

    SciTech Connect

    Metlyaev, E.G.; Novikova, N.J.

    2012-07-01

    Disposal of and use of wastes containing natural radioactive material (NORM) or technologically enhanced natural radioactive material (TENORM) with excessive natural background as a building material is very important in the supervision body activity. At the present time, the residents of Octyabrsky village are under resettlement. This village is located just near the Priargunsky mining and chemical combine (Ltd. 'PPGHO'), one of the oldest uranium mines in our country. The vacated wooden houses in the village are demolished and partly used as a building material. To address the issue of potential radiation hazard of the wooden beams originating from demolition of houses in Octyabrsky village, the contents of the natural radionuclides (K-40, Th-232, Ra-226, U- 238) are being determined in samples of the wooden beams of houses. The NORM contents in the wooden house samples are higher, on average, than their content in the reference sample of the fresh wood shavings, but the range of values is rather large. According to the classification of waste containing the natural radionuclides, its evaluation is based on the effective specific activity. At the effective specific activity lower 1.5 kBq/kg and gamma dose rate lower 70 μR/h, the material is not considered as waste and can be used in building by 1 - 3 classes depending upon A{sub eff} value. At 1.5 kBq/kg < A{sub eff} ≤ 4 kBq/kg (4 class), the wooden beams might be used for the purpose of the industrial building, if sum of ratios between the radionuclide specific activity and its specific activity of minimum significance is lower than unit. The material classified as the waste containing the natural radionuclides has A{sub eff} higher 1.5 kBq /kg, and its usage for the purpose of house-building and road construction is forbidden. As for the ash classification and its future usage, such usage is unreasonable, because, according to the provided material, more than 50% of ash samples are considered as radioactive

  13. Natural Radionuclide Activity Concentrations In Spas Of Argentina

    NASA Astrophysics Data System (ADS)

    Gnoni, G.; Czerniczyniec, M.; Canoba, A.; Palacios, M.

    2008-08-01

    Geothermal waters have been used on a large scale for bathing, drinking and medical purposes. These waters can contain natural radionuclides that may increase the exposure to people. In this work the most important natural radionuclide activity concentrations in different thermal spas of Argentina were measured to characterize waters and to evaluate the exposure of workers and members of the public.

  14. Monitored natural attenuation forum: MNA of metals and radionuclides

    EPA Science Inventory

    While the natural attenuation of many organic compounds is established and accepted by the regulated and regulatory communities, there is some debate whether monitored natural attenuation (MNA) of metals and radionuclides is a reasonable remedial alternative to consider. Do you...

  15. Monitored Natural Attenuation For Radionuclides In Ground Water - Technical Issues

    EPA Science Inventory

    Remediation of ground water contaminated with radionuclides may be achieved using attenuation-based technologies. These technologies may rely on engineered processes (e.g., bioremediation) or natural processes (e.g., monitored natural attentuation) within the subsurface. In gen...

  16. Monitored Natural Attenuation For Radionuclides In Ground Water - Technical Issues

    EPA Science Inventory

    Remediation of ground water contaminated with radionuclides may be achieved using attenuation-based technologies. These technologies may rely on engineered processes (e.g., bioremediation) or natural processes (e.g., monitored natural attentuation) within the subsurface. In gen...

  17. Monitored natural attenuation forum: MNA of metals and radionuclides

    EPA Science Inventory

    While the natural attenuation of many organic compounds is established and accepted by the regulated and regulatory communities, there is some debate whether monitored natural attenuation (MNA) of metals and radionuclides is a reasonable remedial alternative to consider. Do you...

  18. Natural radionuclides in Hanford site ground waters

    SciTech Connect

    Smith, M.R.; Laul, J.C.; Johnson, V.G.

    1987-10-01

    Uranium, Th, Ra, Rn, Pb and Po radionuclide concentrations in ground waters from the Hanford Site indicate that U, Th, and Ra are highly sorbed. Relative to Rn, these radionuclides are low by factors of 10/sup -3/ to 10/sup -6/. Uranium sorption is likely due to its reduction from the +6 state, where it is introduced via surface waters, to the +4 state found in the confined aquifers. The distribution of radionuclides is very similar in all of the confined aquifers and significantly different from the distribution observed in the unconfined and surface waters. Barium correlates well with Ra over three orders of magnitude, indicating that stable element analogs may be useful for inferring the behavior of radioactive waste radionuclides in this candidate geologic repository. 8 refs., 7 figs., 1 tab.

  19. Radiological impact of natural radionuclides from soils of Salamanca, Mexico.

    PubMed

    Mandujano-García, C D; Sosa, M; Mantero, J; Costilla, R; Manjón, G; García-Tenorio, R

    2016-11-01

    Salamanca is the centre of a large industrial complex associated with the production and refining of oil-derived products in the state of Guanajuato, Mexico. The city also hosts a large chemical industry, and in past years a major fertilizer industry. All of them followed NORM (naturally occurring radioactive materials) industrial activities, where either raw materials or residues enriched in natural radionuclides are handled or generated, which can have an environmental radiological impact on their environmental compartments (e.g. soils and aquatic systems). In this study, activity concentrations of radionuclides from the (238)U and (232)Th natural series present in superficial urban soils surrounding an industrial complex in Salamanca, México, have been determined to analyse the possible environmental radiological impact of some of the industrial activities. The alpha-particle and gamma-ray spectrometry is used for the radiometric characterization. The results revealed the presence of 10-42, 11-51 and 178-811Bq/kg of (238)U, (232)Th and (40)K, respectively, without any clear anthropogenic increment in relation to the values normally found in unaffected soils. Thus, the radioactive impact of the industrial activities on the surrounding soils can be evaluated as very low, representing no radiological risk for the health of the population.

  20. Risk Due to Radiological Terror Attacks With Natural Radionuclides

    SciTech Connect

    Friedrich, Steinhaeusler; Lyudmila, Zaitseva; Stan, Rydell

    2008-08-07

    The naturally occurring radionuclides radium (Ra-226) and polonium (Po-210) have the potential to be used for criminal acts. Analysis of international incident data contained in the Database on Nuclear Smuggling, Theft and Orphan Radiation Sources (CSTO), operated at the University of Salzburg, shows that several acts of murder and terrorism with natural radionuclides have already been carried out in Europe and Russia. Five different modes of attack (T) are possible: (1) Covert irradiation of an individual in order to deliver a high individual dose; (2) Covert irradiation of a group of persons delivering a large collective dose; (3) Contamination of food or drink; (4) Generation of radioactive aerosols or solutions; (5) Combination of Ra-226 with conventional explosives (Dirty Bomb).This paper assesses the risk (R) of such criminal acts in terms of: (a) Probability of terrorist motivation deploying a certain attack mode T; (b) Probability of success by the terrorists for the selected attack mode T; (c) Primary damage consequence (C) to the attacked target (activity, dose); (d) Secondary damage consequence (C') to the attacked target (psychological and socio-economic effects); (e) Probability that the consequences (C, C') cannot be brought under control, resulting in a failure to manage successfully the emergency situation due to logistical and/or technical deficits in implementing adequate countermeasures. Extensive computer modelling is used to determine the potential impact of such a criminal attack on directly affected victims and on the environment.

  1. Risk Due to Radiological Terror Attacks With Natural Radionuclides

    NASA Astrophysics Data System (ADS)

    Friedrich, Steinhäusler; Stan, Rydell; Lyudmila, Zaitseva

    2008-08-01

    The naturally occurring radionuclides radium (Ra-226) and polonium (Po-210) have the potential to be used for criminal acts. Analysis of international incident data contained in the Database on Nuclear Smuggling, Theft and Orphan Radiation Sources (CSTO), operated at the University of Salzburg, shows that several acts of murder and terrorism with natural radionuclides have already been carried out in Europe and Russia. Five different modes of attack (T) are possible: (1) Covert irradiation of an individual in order to deliver a high individual dose; (2) Covert irradiation of a group of persons delivering a large collective dose; (3) Contamination of food or drink; (4) Generation of radioactive aerosols or solutions; (5) Combination of Ra-226 with conventional explosives (Dirty Bomb). This paper assesses the risk (R) of such criminal acts in terms of: (a) Probability of terrorist motivation deploying a certain attack mode T; (b) Probability of success by the terrorists for the selected attack mode T; (c) Primary damage consequence (C) to the attacked target (activity, dose); (d) Secondary damage consequence (C') to the attacked target (psychological and socio-economic effects); (e) Probability that the consequences (C, C') cannot be brought under control, resulting in a failure to manage successfully the emergency situation due to logistical and/or technical deficits in implementing adequate countermeasures. Extensive computer modelling is used to determine the potential impact of such a criminal attack on directly affected victims and on the environment.

  2. Naturally Occurring Radon and 120(h) transfers

    EPA Pesticide Factsheets

    This page contains a discussion regarding how the presence of naturally occurring radon on closing military bases affects the United States' ability to transfer parcels under §120(h) (3) and §120(h) (4).

  3. TENORM (Technologically Enhanced Naturally Occurring Radioactive Materials)

    MedlinePlus

    ... The major industrial sectors which generate TENORM are: Mining. Energy production. Water treatment. Consumer products . Learn more ... Technologically Enhanced Naturally Occurring Radioactive Materials From Uranium Mining, Volume 1: Mining and Reclamation Background, and Volume ...

  4. Natural contamination in radionuclide detection systems

    SciTech Connect

    Wogman, N.A.

    1980-10-01

    Through the use of low-level gamma-ray spectrometry, clean material for construction of radionuclide detection systems has been identified. In general aluminum contains high quantities of /sup 232/Th and /sup 238/U with minimal quantities of /sup 40/K. Stainless steels contain /sup 60/Co. The radioactive contents of foams, cements, and light reflective materials are quite variable. Molecular sieve materials used in germanium spectrometers contain from 4-9 dpm/g. Only through a judicious choice of materials can a spectrometer with the lowest achievable background be assembled.

  5. Radionuclide partitioning across great lakes natural interfaces

    NASA Astrophysics Data System (ADS)

    Platford, R. F.; Joshi, S. R.

    1989-11-01

    Several water and surface microlayer samples from Lake St. Clair, the Niagara River, and the North Shore of Lake Ontario collected during 1983 1986 have been assayed for a variety of radionuclides. In addition, the foam accumulating in the pool just below Niagara Falls was also analyzed and found to be the most efficient aqueous phase collector of137Cs,210Pb, and226Ra. The order of radioisotope specific activities from highest to lowest is: Lake Ontario sediment, Niagara River suspended solids, Niagara River foam, surface microlayer water, and subsurface water. Radiological dose rates to the sediments from137Cs,226Ra, and228Th total about 5 mGy/y.

  6. Naturally occurring antimicrobials for minimally processed foods.

    PubMed

    Davidson, P Michael; Critzer, Faith J; Taylor, T Matthew

    2013-01-01

    Natural antimicrobials are gaining increased interest from researchers and food manufacturers alike seeking to discover label-friendly alternatives to the widely implemented synthetic compounds. Naturally occurring antimicrobials can be applied directly to food to protect food quality, extend food shelf life by inhibiting or inactivating spoilage microorganisms, and improve food safety by inhibiting or inactivating food-borne pathogens. There are a great number of natural antimicrobials derived from animal, plant, and microbial sources. This manuscript reviews their efficacy against spoilage and pathogenic organisms, their methods of evaluation, and their application in various foods as well as the development of novel delivery systems and incorporation with other hurdles.

  7. Microbial transformations of natural organic compounds and radionuclides in subsurface environments

    SciTech Connect

    Francis, A.J.

    1985-10-01

    A major national concern in the subsurface disposal of energy wastes is the contamination of ground and surface waters by waste leachates containing radionuclides, toxic metals, and organic compounds. Microorganisms play an important role in the transformation of organic compounds, radionuclides, and toxic metals present in the waste and affect their mobility in subsurface environments. Microbial processes involved in dissolution, mobilization, and immobilization of toxic metals under aerobic and anaerobic conditions are briefly reviewed. Metal complexing agents and several organic acids produced by microbial action affect mobilization of radionuclides and toxic metals in subsurface environments. Information on the persistence of and biodegradation rates of synthetic as well as microbiologically produced complexing agents is scarce but important in determining the mobility of metal organic complexes in subsoils. Several gaps in knowledge in the area of microbial transformation of naturally occurring organics, radionuclides, and toxic metals have been identified, and further basic research has been suggested. 31 refs., 1 fig., 3 tabs.

  8. Medicinal significance of naturally occurring cyclotetrapeptides.

    PubMed

    Abdalla, Muna Ali

    2016-10-01

    Bioactive natural products are serendipitous drug candidates, which stimulate synthetic approaches for improving and supporting drug discovery and development. Therefore, the search for bioactive metabolites from different natural sources continues to play an important role in fashioning new medicinal agents. Several cyclic peptides were produced by organisms, such as β-defensins, gramicidin S, and tyrocidine A, and exhibited a wide range of bioactivities, such as antiviral activity against HIV-1, influenza A viruses, or antibacterial activity. Cyclic tetrapeptides are a class of natural products that were found to have a broad range of biological activities, promising pharmacokinetic properties, as well as interesting conformational dynamics and ability of slow inter-conversion to several different structures. Cyclooligopeptides, particularly medium ring-sized peptides, were obtained from marine microorganisms and exhibited a wide range of pharmacological properties, including antimicrobial and anti-dinoflagellate activities, cytotoxicity, and inhibitory activity against enzyme sortase B. Most of the naturally occurring cyclotetrapeptides are obtained from fungi. Some natural cyclic tetrapeptides were found to inhibit histone deacetylase (HDAC), which regulate the expression of genes. These compounds are very useful as cancer therapeutics. Various analogues of the natural cyclotetrapeptides were successfully synthesized to find novel lead compounds for pharmacological and biotechnological applications. Therefore, in this review, previously reported novel natural cyclotetrapeptides are briefly discussed, along with their important biological activities as drug candidates, together with their promising therapeutic properties. Moreover, their future perspective in drug discovery as potential therapeutic agents will be determined.

  9. Naturally occurring products in cancer therapy

    PubMed Central

    Rajesh, E.; Sankari, Leena S.; Malathi, L.; Krupaa, Jayasri R.

    2015-01-01

    Natural products have been used for the treatment of various diseases and are becoming an important research area for drug discovery. These products, especially phytochemicals have been extensively studies and have exhibited anti-carcinogenic activities by interfering with the initiation, development and progression of cancer through the modulation of various mechanisms including cellular proliferation, differentiation, apoptosis, angiogenesis, and metastasis. This concept is gaining attention because it is a cost-effective alternative to cancer treatment. In this article, we have discussed some of the naturally occurring products used in cancer treatment. PMID:26015704

  10. Concentrations of the naturally occurring radionucleides Pb-210, Po-210, and Ra-226 in aquatic fauna

    NASA Technical Reports Server (NTRS)

    Holtzman, R. B.

    1969-01-01

    Study reveals naturally occurring radionuclides are ubiquitous and contribute a substantial fraction of the natural radiation dose to humans and various biota. Measurements may be useful in ecological and other biological problems such as tracing food chains of animals and study of the metabolism of these elements.

  11. Naturally Occuring Fish Poisons from Plants

    NASA Astrophysics Data System (ADS)

    Cannon, Jonathan G.; Burton, Robert A.; Wood, Steven G.; Owen, Noel L.

    2004-10-01

    Since prehistoric times, cultures throughout the world have used piscicidal (fish poisoning) plants for fishing. In recent times, scientists have identified many of the plant compounds responsible for killing the fish and have found that these compounds possess other important biological properties, such as insecticidal and anti-cancer activities. This article reviews some of the chemical research that has been performed on naturally occurring fish poisons, including plant sources, methods of use, toxicity, and mechanisms of action of piscicides.

  12. The enrichment behavior of natural radionuclides in pulverized oil shale-fired power plants.

    PubMed

    Vaasma, Taavi; Kiisk, Madis; Meriste, Tõnis; Tkaczyk, Alan Henry

    2014-12-01

    The oil shale industry is the largest producer of NORM (Naturally Occurring Radioactive Material) waste in Estonia. Approximately 11-12 million tons of oil shale containing various amounts of natural radionuclides is burned annually in the Narva oil shale-fired power plants, which accounts for approximately 90% of Estonian electricity production. The radionuclide behavior characteristics change during the fuel combustion process, which redistributes the radionuclides between different ash fractions. Out of 24 operational boilers in the power plants, four use circulating fluidized bed (CFB) technology and twenty use pulverized fuel (PF) technology. Over the past decade, the PF boilers have been renovated, with the main objective to increase the efficiency of the filter systems. Between 2009 and 2012, electrostatic precipitators (ESP) in four PF energy blocks were replaced with novel integrated desulphurization technology (NID) for the efficient removal of fly ash and SO2 from flue gases. Using gamma spectrometry, activity concentrations and enrichment factors for the (238)U ((238)U, (226)Ra, (210)Pb) and (232)Th ((232)Th, (228)Ra) family radionuclides as well as (40)K were measured and analyzed in different PF boiler ash fractions. The radionuclide activity concentrations in the ash samples increased from the furnace toward the back end of the flue gas duct. The highest values in different PF boiler ash fractions were in the last field of the ESP and in the NID ash, where radionuclide enrichment factors were up to 4.2 and 3.3, respectively. The acquired and analyzed data on radionuclide activity concentrations in different PF boiler ashes (operating with an ESP and a NID system) compared to CFB boiler ashes provides an indication that changes in the fuel (oil shale) composition and boiler working parameters, as well as technological enhancements in Estonian oil shale fired power plants, have had a combined effect on the distribution patterns of natural radionuclides

  13. Natural chelating agents for radionuclide decorporation

    DOEpatents

    Premuzic, E.T.

    1985-06-11

    This invention relates to the production of metal-binding compounds useful for the therapy of heavy metal poisoning, for biological mining and for decorporation of radionuclides. The present invention deals with an orderly and effective method of producing new therapeutically effective chelating agents. This method uses challenge biosynthesis for the production of chelating agents that are specific for a particular metal. In this approach, the desired chelating agents are prepared from microorganisms challenged by the metal that the chelating agent is designed to detoxify. This challenge induces the formation of specific or highly selective chelating agents. The present invention involves the use of the challenge biosynthetic method to produce new complexing/chelating agents that are therapeutically useful to detoxify uranium, plutonium, thorium and other toxic metals. The Pseudomonas aeruginosa family of organisms is the referred family of microorganisms to be used in the present invention to produce the new chelating agent because this family is known to elaborate strains resistant to toxic metals.

  14. Activity size distribution of some natural radionuclides.

    PubMed

    Mohery, M; Abdallah, A M; Al-Amoudi, Z M; Baz, S S

    2014-03-01

    In this study, the results concerning the activity size distribution of the long-lived ((210)Pb) radon decay product aerosols and the thoron decay product aerosols ((212)Pb) and ((7)Be) of the outdoor atmosphere are presented. Also, the mass size distribution of the aerosol particles is determined. The low-pressure Berner cascade impactor Model 20/0.015 was used as a sampling device. The activity size distribution of these radionuclides was determined by one log-normal distribution (accumulation mode) whereas the mass size distribution was by two log-normal distributions (accumulation and coarse mode). The activity median aerodynamic diameter (AMAD) of (212)Pb was found to be 305 nm with a geometric standard deviation (σg) of 2.41. The specific air activity concentration of (212)Pb was found to be 0.14 ± 0.012 Bq m(-3). An AMAD of (210)Pb of 610 nm with σg of 1.8 was determined, whereas that of 550 nm with σg of 1.97 was determined for (7)Be. The specific air activity concentration of (210)Pb and (7)Be was found to be 0.0016±2.5×10(-4) and 0.00348 ± 4×10(-4) Bq m(-3), respectively. Using a dosimetric model, the total deposition fraction as well as the total equivalent dose has been evaluated considering the observed parameters of the activity size distribution of (212)Pb. At a total deposition fraction of ∼21 %, the total equivalent dose was found to be 0.41 µSv.

  15. Attention turns to naturally occurring methane seepage

    NASA Astrophysics Data System (ADS)

    Kvenvolden, Keith A.; Lorenson, Thomas D.; Reeburgh, William S.

    Methane is the most abundant organic compound in the Earth's atmosphere. As a powerful greenhouse gas, it has implications for global climate change. Sources of methane to the atmosphere are varied. Depending on the source, methane can contain either modern or ancient carbon. Methane exiting from swamps and wetlands contains modern carbon, whereas methane leaking from petroleum reservoirs contains ancient carbon. The total annual source of methane to the atmosphere has been constrained to about 540 teragrams (Tg) per year “Cicerone and Oremland, 1988”. Notably absent from any identified sources is the contribution of geologically sourced methane from naturally occurring seepage.

  16. Persulfate activation by naturally occurring trace minerals.

    PubMed

    Teel, Amy L; Ahmad, Mushtaque; Watts, Richard J

    2011-11-30

    The potential for 13 naturally occurring minerals to mediate the decomposition of persulfate and generate a range of reactive oxygen species was investigated to provide fundamental information on activation mechanisms when persulfate is used for in situ chemical oxidation (ISCO). Only four of the minerals (cobaltite, ilmenite, pyrite, and siderite) promoted the decomposition of persulfate more rapidly than persulfate-deionized water control systems. The other nine minerals decomposed persulfate at the same rate or more slowly than the control systems. Mineral-mediated persulfate activation was conducted with the addition of one of three probe compounds to detect the generation of reactive oxygen species: anisole (sulfate+hydroxyl radical), nitrobenzene (hydroxyl radical), and hexachloroethane (reductants and nucleophiles). The reduced mineral pyrite promoted rapid generation of sulfate+hydroxyl radical. However, the remainder of the minerals provided minimal potential for the generation of reactive oxygen species. The results of this research demonstrate that the majority of naturally occurring trace minerals do not activate persulfate to generate reactive oxygen species, and other mechanisms of activation are necessary to promote contaminant destruction in the subsurface during persulfate ISCO.

  17. Natural chelating agents for radionuclide decorporation

    DOEpatents

    Premuzic, Eugene T.

    1988-01-01

    This invention relates to the preparation of new, naturally produced chelating agents as well as to the method and resulting chelates of desorbing cultures in a bioavailable form involving Pseudomonas species or other microorganisms. A preferred microorganism is Pseudomonas aeruginosa which forms multiple chelates with thorium in the range of molecular weight 100-1,000 and also forms chelates with uranium of molecular weight in the area of 100-1,000 and 1,000-2,000.

  18. Tetrahydroberberine, a pharmacologically active naturally occurring alkaloid.

    PubMed

    Pingali, Subramanya; Donahue, James P; Payton-Stewart, Florastina

    2015-04-01

    Tetrahydroberberine (systematic name: 9,10-dimethoxy-5,8,13,13a-tetrahydro-6H-benzo[g][1,3]benzodioxolo[5,6-a]quinolizine), C20H21NO4, a widely distributed naturally occurring alkaloid, has been crystallized as a racemic mixture about an inversion center. A bent conformation of the molecule is observed, with an angle of 24.72 (5)° between the arene rings at the two ends of the reduced quinolizinium core. The intermolecular hydrogen bonds that play an apparent role in crystal packing are 1,3-benzodioxole -CH2···OCH3 and -OCH3···OCH3 interactions between neighboring molecules.

  19. Regulation of naturally occurring radioactive materials in Australia.

    PubMed

    Jeffries, Cameron; Akber, Riaz; Johnston, Andrew; Cassels, Brad

    2011-07-01

    In order to promote uniformity between jurisdictions, the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) has developed the National Directory for Radiation Protection, which is a regulatory framework that all Australian governments have agreed to adopt. There is a large and diverse range of industries involved in mining or mineral processing, and the production of fossil fuels in Australia. Enhanced levels of naturally occurring radionuclides can be associated with mineral extraction and processing, other industries (e.g. metal recycling) and some products (e.g. plasterboard). ARPANSA, in conjunction with industry and State regulators, has undertaken a review and assessment of naturally occurring radioactive material (NORM) management in Australian industries. This review has resulted in guidance on the management of NORM that will be included in the National Directory for Radiation Protection. The first NORM safety guide provides the framework for NORM management and addresses specific NORM issues in oil and gas production, bauxite, aluminium and phosphate industries. Over time further guidance material for other NORM-related industries will be developed. This presentation will provide an overview of the regulatory approach to managing NORM industries in Australia.

  20. Sundew adhesive: a naturally occurring hydrogel

    PubMed Central

    Huang, Yujian; Wang, Yongzhong; Sun, Leming; Agrawal, Richa; Zhang, Mingjun

    2015-01-01

    Bioadhesives have drawn increasing interest in recent years, owing to their eco-friendly, biocompatible and biodegradable nature. As a typical bioadhesive, sticky exudate observed on the stalked glands of sundew plants aids in the capture of insects and this viscoelastic adhesive has triggered extensive interests in revealing the implied adhesion mechanisms. Despite the significant progress that has been made, the structural traits of the sundew adhesive, especially the morphological characteristics in nanoscale, which may give rise to the viscous and elastic properties of this mucilage, remain unclear. Here, we show that the sundew adhesive is a naturally occurring hydrogel, consisting of nano-network architectures assembled with polysaccharides. The assembly process of the polysaccharides in this hydrogel is proposed to be driven by electrostatic interactions mediated with divalent cations. Negatively charged nanoparticles, with an average diameter of 231.9 ± 14.8 nm, are also obtained from this hydrogel and these nanoparticles are presumed to exert vital roles in the assembly of the nano-networks. Further characterization via atomic force microscopy indicates that the stretching deformation of the sundew adhesive is associated with the flexibility of its fibrous architectures. It is also observed that the adhesion strength of the sundew adhesive is susceptible to low temperatures. Both elasticity and adhesion strength of the sundew adhesive reduce in response to lowering the ambient temperature. The feasibility of applying sundew adhesive for tissue engineering is subsequently explored in this study. Results show that the fibrous scaffolds obtained from sundew adhesive are capable of increasing the adhesion of multiple types of cells, including fibroblast cells and smooth muscle cells, a property that results from the enhanced adsorption of serum proteins. In addition, in light of the weak cytotoxic activity exhibited by these scaffolds towards a variety of

  1. Natural and anthropogenic radionuclides in airborne particulate samples collected in Barcelona (Spain).

    PubMed

    Vallés, I; Camacho, A; Ortega, X; Serrano, I; Blázquez, S; Pérez, S

    2009-02-01

    Results for naturally occurring (7)Be, (210)Pb, (40)K, (214)Bi, (214)Pb, (212)Pb, (228)Ac and (208)Tl and anthropogenic (137)Cs in airborne particulate matter in the Barcelona area during the period from January 2001 to December 2005 are presented and discussed. The (212)Pb and (208)Tl, (214)Bi and (214)Pb, (7)Be and (210)Pb radionuclide levels showed a significant correlation with each other, with correlation coefficients of 0.99, 0.78 and 0.69, respectively, suggesting similar origin/behaviour of these radionuclides in the air. Caessium-137 and Potassium-40 were transported to the air as resuspended particle from the soil. The (7)Be and (210)Pb concentrations showed similar seasonal variations, with a tendency for maximum concentrations during the summer months. An inverse relationship was observed between the (7)Be, (210)Pb, (40)K and (137)Cs concentrations and weekly rainfall, indicating washout of atmospheric aerosols carrying these radionuclides.

  2. Naturally occurring contamination in the Mancos Shale.

    PubMed

    Morrison, Stan J; Goodknight, Craig S; Tigar, Aaron D; Bush, Richard P; Gil, April

    2012-02-07

    Some uranium mill tailings disposal cells were constructed on dark-gray shale of the Upper Cretaceous Mancos Shale. Shale of this formation contains contaminants similar to those in mill tailings. To establish the contributions derived from the Mancos, we sampled 51 locations in Colorado, New Mexico, and Utah. Many of the groundwater samples were saline with nitrate, selenium, and uranium concentrations commonly exceeding 250, 000, 1000, and 200 μg/L, respectively. Higher concentrations were limited to groundwater associated with shale beds, but were not correlated with geographic area, stratigraphic position, or source of water. The elevated concentrations suggest that naturally occurring contamination should be considered when evaluating groundwater cleanup levels. At several locations, seep water was yellow or red, caused in part by dissolved organic carbon concentrations up to 280 mg/L. Most seeps had (234)U to (238)U activity ratios greater than 2, indicating preferential leaching of (234)U. Seeps were slightly enriched in (18)O relative to the meteoric water line, indicating limited evaporation. Conceptually, major ion chemical reactions are dominated by calcite dissolution following proton release from pyrite oxidation and subsequent exchange by calcium for sodium residing on clay mineral exchange sites. Contaminants are likely released from organic matter and mineral surfaces during weathering.

  3. Measurements of Natural Radionuclides in Vegetables by Gamma Spectrometry

    NASA Astrophysics Data System (ADS)

    Saeed, M. A.; Zainal, N. Jenal; Hossain, I.; Javed, M. A.; Mubarak, A. A.

    2014-07-01

    This article reports the activity of natural radionuclides uranium, thorium, and potassium, in different vegetables in Malaysia, measured with a p-type high-purity germanium detector (HPGe). Potassium radionuclides were the most prevalent element in the tested samples, whose activity ranges from 138.89 to 2660.31 Bq/kg. Meanwhile, the activity of uranium was found to be within the minimum detection limit (MDL) to 46.94 Bq/kg, and thorium from < MDL to 192.98 Bq/kg. The annual dose was in the range 0.001 to 0.06 mSv, within the worldwide range of 0.29 mSv/year for ingestion of vegetables.

  4. Natural Radionuclides and Isotopic Signatures for Determining Carbonaceous Aerosol Sources, Aerosol Lifetimes, and Washout Processes

    SciTech Connect

    Gaffney, Jeffrey

    2012-12-12

    This is the final technical report. The project description is as follows: to determine the role of aerosol radiative forcing on climate, the processes that control their atmospheric concentrations must be understood, and aerosol sources need to be determined for mitigation. Measurements of naturally occurring radionuclides and stable isotopic signatures allow the sources, removal and transport processes, as well as atmospheric lifetimes of fine carbonaceous aerosols, to be evaluated.

  5. Characterization of Contaminant Transport Using Naturally-Occurring U-Series Disequilibria

    SciTech Connect

    TEH-LUNG KU

    2001-06-01

    Study the migration of nuclear waste contaminants in subsurface fractured systems using naturally occurring uranium and thorium-series radionuclides as tracers under in-situ physico-chemical and hydrogeologic conditions. Radioactive disequilibria among members of these decay-series nuclides can provide information on the rates of adsorption-desorption and transport of contaminants as well as on fluid transport and rock dissolution in a natural setting.

  6. Scrap metal management issues associated with naturally occurring radioactive material

    SciTech Connect

    Smith, K.P.; Blunt, D.L.

    1995-08-01

    Certain industrial processes sometimes generate waste by-products that contain naturally occurring radioactive material (NORM) at elevated concentrations. Some industries, including the water treatment, geothermal energy, and petroleum industries, generate scrap metal that may be contaminated with NORM wastes. Of these three industries, the petroleum industry probably generates the largest quantity of NORM-contaminated equipment, conservatively estimated at 170,000 tons per year. Equipment may become contaminated when NORM-containing scale or sludge accumulates inside water-handling equipment. The primary radionuclides of concern in these NORM wastes are radium-226 and radium-228. NORM-contaminated equipment generated by the petroleum industry currently is managed several ways. Some equipment is routinely decontaminated for reuse; other equipment becomes scrap metal and may be disposed of by burial at a licensed landfill, encapsulation inside the wellbore of an abandoned well, or shipment overseas for smelting. In view of the increased regulatory activities addressing NORM, the economic burden of managing NORM-contaminated wastes, including radioactive scrap metal, is likely to continue to grow. Efforts to develop a cost-effective strategy for managing radioactive scrap metal should focus on identifying the least expensive disposition options that provide adequate protection of human health and the environment. Specifically, efforts should focus on better characterizing the quantity of radioactive scrap available for recycle or reuse, the radioactivity concentration levels, and the potential risks associated with different disposal options.

  7. A comparison of the dose from natural radionuclides and artificial radionuclides after the Fukushima nuclear accident

    PubMed Central

    Hosoda, Masahiro; Tokonami, Shinji; Omori, Yasutaka; Ishikawa, Tetsuo; Iwaoka, Kazuki

    2016-01-01

    Due to the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, the evacuees from Namie Town still cannot reside in the town, and some continue to live in temporary housing units. In this study, the radon activity concentrations were measured at temporary housing facilities, apartments and detached houses in Fukushima Prefecture in order to estimate the annual internal exposure dose of residents. A passive radon–thoron monitor (using a CR-39) and a pulse-type ionization chamber were used to evaluate the radon activity concentration. The average radon activity concentrations at temporary housing units, including a medical clinic, apartments and detached houses, were 5, 7 and 9 Bq m−3, respectively. Assuming the residents lived in these facilities for one year, the average annual effective doses due to indoor radon in each housing type were evaluated as 0.18, 0.22 and 0.29 mSv, respectively. The average effective doses to all residents in Fukushima Prefecture due to natural and artificial sources were estimated using the results of the indoor radon measurements and published data. The average effective dose due to natural sources for the evacuees from Namie Town was estimated to be 1.9 mSv. In comparison, for the first year after the FDNPP accident, the average effective dose for the evacuees due to artificial sources from the accident was 5.0 mSv. Although residents' internal and external exposures due to natural radionuclides cannot be avoided, it might be possible to lower external exposure due to the artificial radionuclides by changing some behaviors of residents. PMID:26838130

  8. Naturally occurring esterification reactions with bryostatin.

    PubMed

    Abadi, Giso; Manning, Thomas J; McLeod, Kristen; Phillips, Dennis; Groundwater, Paul; Noble, Lyn; Potter, Thomas

    2008-01-01

    Bryostatin structures share a commonality of a central bryophan ring, but each differs due to two groups (R(1) and R(2)) that are attached to the bryophan ring via ester bonds. This research examines the impact that conditions such as UV light, acidic and basic conditions can have on the bryostatin structure in the presence of octanoic acid and water. Mass spectrometry (MS) measurements suggest that bryostatin can easily rearrange into various structures under natural conditions by reacting with carboxylates that are ubiquitous in nature. A second set of measurements suggest bryostatin can be hydrolyzed by water, a reaction that has significant implications in both medicinal applications and extraction procedures.

  9. Phytochemistry and pharmacognosy of naturally occurring prenyloxyanthraquinones.

    PubMed

    Epifano, Francesco; Fiorito, Serena; Carlucci, Giuseppe; Locatelli, Marcello; Genovese, Salvatore

    2013-08-01

    Several natural compounds containing an anthraquinone core linked to a prenyloxy chain have been reported in the literature in recent years. The discovery in the plant kingdom of such secondary metabolites is a novel acquisition in the phytochemistry research field and in many cases led to a re-consideration of the secondary metabolite pool of well known anthraquinone-containing plants. In this review article we will focus on the phytochemistry and pharmacognosy of prenyloxyanthraquinones putting in evidence the natural sources and their biological properties as anti-microbial and anticancer agents.

  10. Tetrahedral boron in naturally occurring tourmaline

    SciTech Connect

    Tagg, S.L.; Cho, H.; Dyar, M.D.; Grew, E.S.

    1999-09-01

    Evidence for boron in both trigonal and tetrahedral coordination has been found in {sup 11}B magic-angle-spinning (MAS) nuclear magnetic resonance (NMR) spectra of natural, inclusion-free specimens of aluminum-rich lithian tourmaline from granitic pregmatites.

  11. Naturally Occurring Fish Poisons from Plants

    ERIC Educational Resources Information Center

    Cannon, Jonathan G.; Burton, Robert A.; Wood, Steven G.; Owen, Noel L.

    2004-01-01

    The fish poisons derived from plants used throughout the world, not only as piscicides but also for a range of other uses, including insecticident and in folk medicines, is presented. The aim of this review is to provide a useful background for students interested in natural products.

  12. Naturally Occurring Fish Poisons from Plants

    ERIC Educational Resources Information Center

    Cannon, Jonathan G.; Burton, Robert A.; Wood, Steven G.; Owen, Noel L.

    2004-01-01

    The fish poisons derived from plants used throughout the world, not only as piscicides but also for a range of other uses, including insecticident and in folk medicines, is presented. The aim of this review is to provide a useful background for students interested in natural products.

  13. Natural radionuclide and plutonium content in Black Sea bottom sediments

    SciTech Connect

    Strezov, A.; Stoilova, T.; Yordanova, I.

    1996-01-01

    The content of uranium, thorium, radium, lead, polonium, and plutonium in bottom sediments and algae from two locations at the Bulgarian Black Sea coast have been determined. Some parent:progeny ratios for evaluation of the geochemical behavior of the nuclides have been estimated as well. The extractable and total uranium and thorium are determined by two separate radiochemical procedures to differentiate the more soluble chemical forms of the elements and to estimate the potential hazard for the biosphere and for humans. No distinct seasonal variation as well as no significant change in total and extractable uranium (also for {sup 226}Ra) content is observed. The same is valid for extractable thorium while the total thorium content in the first two seasons is slightly higher. Our data show that {sup 210}Po content is accumulated more in the sediments than {sup 210}Pb, and the evaluated disequilibria suggest that the two radionuclides belong to more recent sediment layers deposited in the slime samples compared to the silt ones for the different seasons. The obtained values for plutonium are in the lower limits of the data cited in literature, which is quite clear as there are no plutonium discharge facilities at the Bulgarian Black Sea coast. The obtained values for the activity ratio {sup 238}Pu: {sup 239+240}Pu are higher for Bjala sediments compared to those of Kaliakra. The ratio values are out of the variation range for the global contamination with weapon tests fallout plutonium which is probably due to Chernobyl accident contribution. The dependence of natural radionuclide content on the sediment type as well as the variation of nuclide accumulation for two types of algae in two sampling locations for five consecutive seasons is evaluated. No serious contamination with natural radionuclides in the algae is observed. 38 refs., 6 figs., 7 tabs.

  14. Natural radionuclide and plutonium content in Black Sea bottom sediments.

    PubMed

    Strezov, A; Yordanova, I; Pimpl, M; Stoilova, T

    1996-01-01

    The content of uranium, thorium, radium, lead, polonium, and plutonium in bottom sediments and algae from two locations at the Bulgarian Black Sea coast have been determined. Some parent:progeny ratios for evaluation of the geochemical behavior of the nuclides have been estimated as well. The extractable and total uranium and thorium are determined by two separate radiochemical procedures to differentiate the more soluble chemical forms of the elements and to estimate the potential hazard for the biosphere and for humans. No distinct seasonal variation as well as no significant change in total and extractable uranium (also for 226Ra) content is observed. The same is valid for extractable thorium while the total thorium content in the first two seasons is slightly higher. Our data show that 210Po content is accumulated more in the sediments than 210Pb, and the evaluated disequilibria suggest that the two radionuclides belong to more recent sediment layers deposited in the slime samples compared to the silt ones for the different seasons. The obtained values for plutonium are in the lower limits of the data cited in literature, which is quite clear as there are no plutonium discharge facilities at the Bulgarian Black Sea coast. The obtained values for the activity ratio 238Pu:239 + 240Pu are higher for Bjala sediments compared to those of Kaliakra. The ratio values are out of the variation range for the global contamination with weapon tests fallout plutonium which is probably due to Chernobyl accident contribution. The dependence of natural radionuclide content on the sediment type as well as the variation of nuclide accumulation for two types of algae in two sampling locations for five consecutive seasons is evaluated. No serious contamination with natural radionuclides in the algae is observed.

  15. IMPACTS OF SOLUBILITY AND OTHER GEOCHEMICAL PROCESSES ON RADIONUCLIDE RETARDATION IN THE NATURAL SYSTEM

    SciTech Connect

    B. Arnold

    2005-08-02

    This report documents results and findings of a study of solubility/co-precipitation effects and enhanced sorption due to variations in redox conditions on radionuclide transport in the natural system (BSC 2005 [DIRS 173951]; BSC 2005 [DIRS 173859]) conducted in response to DOE Contracting Officer Authorization Letter 05-001, Item d (Mitchell 2005 [DIRS 173265]). The purpose of this study is to assess the potential impacts of precipitation and enhanced sorption due to variations in redox conditions on radionuclide transport in the saturated zone (SZ) at Yucca Mountain. The information presented in this report is intended to aid in assessing the conservatism in the SZ transport model for supporting the total system performance assessment (TSPA) calculations. A similar study was performed for the impact of solubility/precipitation on radionuclide transport in the unsaturated zone (UZ). However, because the unsaturated zone is under predominantly oxidizing conditions and that the radionuclides released from the engineered barrier system are not expected to precipitate in the UZ for the reasons described below, it was concluded that the effect on unsaturated zone transport is not significant to warrant a detailed study. Solubility limiting conditions for neptunium in the UZ are expected to be similar to the conditions for neptunium solubility in the waste emplacement drift invert, where Np{sub 2}O{sub 5} is recommended as the controlling solid phase (BSC 2005 [DIRS 174566], Section 6.6.1). Solubility limits for neptunium inside the waste package, however, are expected to be controlled by NpO{sub 2} (BSC 2005 [DIRS 174566], Section 6.6.1). The solubility limits for Np2O5 are generally much higher than for NpO{sub 2} (BSC 2005 [DIRS 174566], Tables 6.6-4 and 6.6-7). Therefore, the low concentrations of neptunium releases from waste packages are unlikely to be affected by solubility limits in the unsaturated zone. The SZ is part of the Lower Natural Barrier to the

  16. Dog models of naturally occurring cancer.

    PubMed

    Rowell, Jennie L; McCarthy, Donna O; Alvarez, Carlos E

    2011-07-01

    Studies using dogs provide an ideal solution to the gap in animal models for natural disease and translational medicine. This is evidenced by approximately 400 inherited disorders being characterized in domesticated dogs, most of which are relevant to humans. There are several hundred isolated populations of dogs (breeds) and each has a vastly reduced genetic variation compared with humans; this simplifies disease mapping and pharmacogenomics. Dogs age five- to eight-fold faster than do humans, share environments with their owners, are usually kept until old age and receive a high level of health care. Farseeing investigators recognized this potential and, over the past decade, have developed the necessary tools and infrastructure to utilize this powerful model of human disease, including the sequencing of the dog genome in 2005. Here, we review the nascent convergence of genetic and translational canine models of spontaneous disease, focusing on cancer.

  17. Estrogenic activity of naturally occurring anthocyanidins.

    PubMed

    Schmitt, E; Stopper, H

    2001-01-01

    Anthocyanins, which are natural plant pigments from the flavonoid family, represent substantial constituents of the human diet. Because some other bioflavonoids are known to have estrogenic activity, the aim of this study was to determine the estrogenic activity of the anthocyanine aglycones. Binding affinity to the estrogen receptor-alpha was 10,000- to 20,000-fold lower than that of the endogenous estrogen estradiol. In the estrogen receptor-positive cell line MCF-7, the anthocyanidins induced expression of a reporter gene. The tested anthocyanidins showed estrogen-inducible cell proliferation in two cell lines (MCF-7 and BG-1), but not in the receptor-negative human breast cancer cell line MDA-MB-231. The phytoestrogen-induced cell proliferation could be blocked by addition of the receptor antagonist 4-hydroxytamoxifen. Combination treatments with the endogenous estrogen estradiol resulted in a reduction of estradiol-induced cell proliferation. Overall, the tested anthocyanidins exert estrogenic activity, which might play a role in altering the development of hormone-dependent adverse effects.

  18. Natural analogue studies of the role of colloids, natural organics and microorganisms on radionuclide transport

    SciTech Connect

    McCarthy, J.F.

    1994-10-01

    Colloids may be important as a geochemical transport mechanism for radionuclides at geological repositories if they are (1) present in the groundwater, (2) stable with respect to both colloidal and chemical stabilities, (3) capable of adsorbing radionuclides, especially if the sorption is irreversible, and (4) mobile in the subsurface. The available evidence from natural analogue and other field studies relevant to these issues is reviewed, as is the potential role of mobile microorganisms ({open_quotes}biocolloids{close_quotes}) on radionuclide migration. Studies have demonstrated that colloids are ubiquitous in groundwater, although colloid concentrations in deep, geochemically stable systems may be too low to affect radionuclide transport. However, even low colloid populations cannot be dismissed as a potential concern because colloids appear to be stable, and many radionuclides that adsorb to colloids are not readily desorbed over long periods. Field studies offer somewhat equivocal evidence concerning colloid mobility and cannot prove or disprove the significance of colloid transport in the far-field environment. Additional research is needed at new sites to properly represent a repository far-field. Performance assessment would benefit from natural analogue studies to examine colloid behavior at sites encompassing a suite of probable groundwater chemistries and that mimic the types of formations selected for radioactive waste repositories.

  19. Factors affecting the distribution of natural and anthropogenic radionuclides in the coastal Burullus Lake.

    PubMed

    El-Reefy, H I; Badran, H M; Sharshar, T; Hilal, M A; Elnimr, T

    2014-08-01

    In the present study, measurements of naturally occurring radioactive materials and (137)Cs activity in sediment were conducted for locations covering the entire Burullus Lake in order to gather information about radionuclides mobility and distribution. Low-background γ-spectrometry was employed to determine the activity concentrations of water and sediment samples. The activity concentrations of (226)Ra and (232)Th are close to uniform distribution in the lake environment. Among the different physical and chemical characteristics measured for water and sediment, only salinity and total organic matter content have the potential to affect the mobility of (137)Cs and (40)K. The results suggest that these two radionuclides are attached to different mobile particulates. Increasing salinity tends to strengthen the adsorption of (137)Cs and solubilization of (40)K in sediment. On the other hand, sediment with high organic matter content traps (137)Cs and (40)K associated particulates to bottom sediment.

  20. Absorbed Gamma-Ray Doses due to Natural Radionuclides in Building Materials

    SciTech Connect

    Aguiar, Vitor A. P.; Medina, Nilberto H.; Moreira, Ramon H.; Silveira, Marcilei A. G.

    2010-05-21

    This work is devoted to the application of high-resolution gamma-ray spectrometry in the study of the effective dose coming from naturally occurring radionuclides, namely {sup 40}K, {sup 232}Th and {sup 238}U, present in building materials such as sand, cement, and granitic gravel. Four models were applied to estimate the effective dose and the hazard indices. The maximum estimated effective dose coming from the three reference rooms considered is 0.90(45) mSv/yr, and maximum internal hazard index is 0.77(24), both for the compact clay brick reference room. The principal gamma radiation sources are cement, sand and bricks.

  1. Analysis of reserve pit sludge from unconventional natural gas hydraulic fracturing and drilling operations for the presence of technologically enhanced naturally occurring radioactive material (TENORM).

    PubMed

    Rich, Alisa L; Crosby, Ernest C

    2013-01-01

    Soil and water (sludge) obtained from reserve pits used in unconventional natural gas mining was analyzed for the presence of technologically enhanced naturally occurring radioactive material (TENORM). Samples were analyzed for total gamma, alpha, and beta radiation, and specific radionuclides: beryllium, potassium, scandium, cobalt, cesium, thallium, lead-210 and -214, bismuth-212 and -214, radium-226 and -228, thorium, uranium, and strontium-89 and -90. Laboratory analysis confirmed elevated beta readings recorded at 1329 ± 311 pCi/g. Specific radionuclides present in an active reserve pit and the soil of a leveled, vacated reserve pit included 232Thorium decay series (228Ra, 228Th, 208Tl), and 226Radium decay series (214Pb, 214Bi, 210Pb) radionuclides. The potential for impact of TENORM to the environment, occupational workers, and the general public is presented with potential health effects of individual radionuclides. Current oversight, exemption of TENORM in federal and state regulations, and complexity in reporting are discussed.

  2. Biotransformations of Plutonium and Uranium by Naturally-Occurring Bacteria

    SciTech Connect

    Boukhalfa, Hakim; Icopini, Gary A.; Lack, Joe G.; Reilly, Sean D.; Hersman, Larry E.; Ruggiero, Christy E.; John, Seth G.; Neu, Mary P.

    2004-03-17

    DOE sites are contaminated by radionuclides and toxic metals, which are in contact with organic contaminants, reactive minerals, and diverse populations of microorganisms. Actinide species to be stabilized or mobilized in situ via direct and indirect chemical, biological, and geochemical processes. Actinide contamination tends to be broadly dispersed and present at low concentrations and therefore prohibitively costly to remove using conventional methods. Pu contamination is particularly challenging because of personnel exposure concerns and a lack of disposal sites. Bacterial bioremediation is a preferable treatment approach. Given that the radionuclides of most concern to the NABIR program are generally more mobile in their oxidized forms (e.g. Pu(VI), Pu(V), U(VI), Tc(VII), Cr(VI)), proposed biostabilization strategies are generally based upon either in situ sequestration of the oxidized form (e.g. actinide biosorption and bioaccumulation within exopolymers and biofilms) or biomineralization of the reduced form (e.g., direct or indirect production of insoluble hydroxides by DMRB). The feasibility of these approaches is affected by the speciation of actinides under environment conditions. For example, actinides can form complexes with co-contaminants (e.g. EDTA) or natural chelators like siderophores and biopolymers. Resulting complexes can interact with bacteria in several ways to yield biostabilized products or more mobile species that could persist. They are investigating how organic chelators affect the speciation and biotransformation of U and Pu. Previously, they reported how these siderophores bind, desorb and solubilize radionuclides. Here they present new results on EDTA complexation, siderophore-mediated Pu accumulation by aerobic bacteria, and initial studies of Pu reduction by DMRB.

  3. Evaluation of natural radionuclides in Brazilian underground mines

    NASA Astrophysics Data System (ADS)

    Santos, T. O.; Rocha, Z.; Vasconcelos, V.; Lara, E. G.; Palmieri, H. E. L.; Cruz, P.; Gouvea, V. A.; Siqueira, J. B.; Oliveira, A. H.

    2015-11-01

    Mineral processing releases long and short half-life radionuclides generating potential exposure to miners. They are internally exposed to radon, thoron and their short-life decay products and, externally, to the gamma emitters scattered in the rock and dust of the mine. Concerning to radiological hazards to workers, this paper focuses on the characterization of the natural radioactivity in the Brazilian underground mines. The radon and its progeny concentrations were measured by using AlphaGUARD and DOSEman detectors, respectively. Radon concentration measurement in groundwater was performed by using RAD7 detector. The 238U and 232Th activity concentration in ore and soil samples were determined by ICPMS. Gamma spectrometry was used to determined 226Ra, 228Ra and 40K activity concentrations. The average radon concentration ranged from 113 to 4964 Bq m-3 and the average Equilibrium Equivalent Concentration varied from 76 to 1174 Bq m-3. Based on these data, the total annual effective dose for the miners was estimated. The results suggest the need of establishing monitoring and control procedures in some mines.

  4. Natural radionuclides in major aquifer systems of the Paraná sedimentary basin, Brazil.

    PubMed

    Bonotto, Daniel Marcos

    2011-10-01

    This paper describes the natural radioactivity of groundwater occurring in sedimentary (Bauru and Guarani) and fractured rock (Serra Geral) aquifer systems in the Paraná sedimentary basin, South America that is extensively used for drinking purposes, among others. The measurements of gross alpha and gross beta radioactivity as well the activity concentration of the natural dissolved radionuclides ⁴⁰K, ²³⁸U, ²³⁴U, ²²⁶Ra, ²²²Rn, ²¹⁰Po and ²¹⁰Pb were held in 80 tubular wells drilled in 21 municipalities located at São Paulo State and its border with Mato Grosso do Sul State in Brazil. Most of the gross alpha radioactivity data were below 1 mBq/L, whereas values exceeding the gross beta radioactivity detection limit of 30 mBq/L were found. The radioelement solubility in the studied systems varied according to the sequence radon>radium>other radionuclides and the higher porosity of sandstones relatively to basalts and diabases could justify the enhanced presence of dissolved radon in the porous aquifer. The implications of the data obtained in terms of standards established for defining the drinking water quality have also been discussed. The population-weighted average activity concentration for these radionuclides was compared to the guideline value of 0.1 mSv/yr for the total effective dose and discussed in terms of the choice of the dose conversion factors. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Comparative Toxicology of Libby Amphibole and Naturally Occurring Asbestos

    EPA Science Inventory

    Summary sentence: Comparative toxicology of Libby amphibole (LA) and site-specific naturally occurring asbestos (NOA) provides new insights on physical properties influencing health effects and mechanisms of asbestos-induced inflammation, fibrosis, and tumorigenesis.Introduction/...

  6. Comparative Toxicology of Libby Amphibole and Naturally Occurring Asbestos

    EPA Science Inventory

    Summary sentence: Comparative toxicology of Libby amphibole (LA) and site-specific naturally occurring asbestos (NOA) provides new insights on physical properties influencing health effects and mechanisms of asbestos-induced inflammation, fibrosis, and tumorigenesis.Introduction/...

  7. An accurate method to measure alpha-emitting natural radionuclides in atmospheric filters: Application in two NORM industries

    NASA Astrophysics Data System (ADS)

    Lozano, R. L.; Bolívar, J. P.; San Miguel, E. G.; García-Tenorio, R.; Gázquez, M. J.

    2011-12-01

    In this work, an accurate method for the measurement of natural alpha-emitting radionuclides from aerosols collected in air filters is presented and discussed in detail. The knowledge of the levels of several natural alpha-emitting radionuclides (238U, 234U, 232Th, 230Th, 228Th, 226Ra and 210Po) in atmospheric aerosols is essential not only for a better understanding of the several atmospheric processes and changes, but also for a proper evaluation of the potential doses, which can inadvertently be received by the population via inhalation. The proposed method takes into account the presence of intrinsic amounts of these radionuclides in the matrices of the quartz filters used, as well as the possible variation in the humidity of the filters throughout the collection process. In both cases, the corrections necessary in order to redress these levels have been evaluated and parameterized. Furthermore, a detailed study has been performed into the optimisation of the volume of air to be sampled in order to increase the accuracy in the determination of the radionuclides. The method as a whole has been applied for the determination of the activity concentrations of U- and Th-isotopes in aerosols collected at two NORM (Naturally Occurring Radioactive Material) industries located in the southwest of Spain. Based on the levels found, a conservative estimation has been performed to yield the additional committed effective doses to which the workers are potentially susceptible due to inhalation of anthropogenic material present in the environment of these two NORM industries.

  8. Hydrogeological interpretation of natural radionuclide contents in Austrian groundwaters

    NASA Astrophysics Data System (ADS)

    Schubert, Gerhard; Berka, Rudolf; Hörhan, Thomas; Katzlberger, Christian; Landstetter, Claudia; Philippitsch, Rudolf

    2010-05-01

    The Austrian Agency for Health and Food Safety (AGES) stores comprehensive data sets of radionuclide contents in Austrian groundwater. There are several analyses concerning Rn-222, Ra-226, gross alpha and gross beta as well as selected analyses of Ra-228, Pb-210, Po-210, Uranium and U-234/U-238. In a current project financed by the Austrian Federal Ministry of Agriculture, Forestry, Environment and Water Management, AGES and the Geological Survey of Austria (GBA) are evaluating these data sets with regard to the geological backgrounds. Several similar studies based on groundwater monitoring have been made in the USA (for instance by Focazio, M.J., Szabo, Z., Kraemer, T.F., Mullin, A.H., Barringer, T.H., De Paul, V.T. (2001): Occurrence of selected radionuclides in groundwater used for drinking water in the United States: a reconnaissance survey, 1998. U.S. Geological Survey Water-Resources Investigations Report 00-4273). The geological background for the radionuclide contents of groundwater will be derived from geological maps in combination with existing Thorium and Uranium analyses of the country rocks and stream-sediments and from airborne radiometric maps. Airborne radiometric data could contribute to identify potential radionuclide hot spot areas as only airborne radiometric mapping could provide countrywide Thorium and Uranium data coverage in high resolution. The project will also focus on the habit of the sampled wells and springs and the hydrological situation during the sampling as these factors can have an important influence on the Radon content of the sampled groundwater (Schubert, G., Alletsgruber, I., Finger, F., Gasser, V., Hobiger, G. and Lettner, H. (2010): Radon im Grundwasser des Mühlviertels (Oberösterreich) Grundwasser. - Springer (in print). Based on the project results an overview map (1:500,000) concerning the radionuclide potential should be produced. The first version should be available in February 2011.

  9. Performance assessment model development and parameter acquisition for analysis of the transport of natural radionuclides in a Mediterranean watershed.

    PubMed

    Agüero, Almudena

    2005-09-15

    This paper describes the methodology developed to construct a model for predicting the behaviour of the natural radioisotopes of U, Th and Ra in a Mediterranean watershed. The methodology includes the development of the performance assessment model, obtaining water flow and radiological parameters based on experimental data and analysis of results. The model, which accounts for both water flows and mass balances of the radionuclides in a semi-natural environment, provides assessments of radionuclide behaviour in grassland and agricultural soils, rivers and reservoirs, including the processes of radionuclide migration through land and water and interactions between both. From field and laboratory data, it has been possible to obtain parameters for the driving processes considered in the model, water fluxes, source term definition, soil to plant transfer factors and distribution coefficient values. Ranges of parameter values obtained have shown good agreement with published literature data. This general methodological approach was developed to be extended to other radionuclides for the modelling of a biosphere watershed in the context of performance assessment of a High Level Waste (HLW) repository under Mediterranean climate conditions, as well as for forecasting radionuclide transport under similar Mediterranean conditions that will occur in the future in other areas. The application of sensitivity and uncertainty analysis was intended to identify key uncertainties with the aim of setting priorities for future research. The model results for the activity concentration in the reservoir indicate that for (238)U and (230)Th the most relevant parameter is the initial concentrations of the radionuclides in the reservoir sediments. However, for (226)Ra the most important parameter is the precipitation rate over the whole watershed.

  10. Enhancement of natural radionuclides in the surroundings of the four largest coal-fired power plants in Spain.

    PubMed

    Baeza, A; Corbacho, J A; Guillén, J; Salas, A; Mora, J C; Robles, B; Cancio, D

    2012-03-01

    The production of electricity in coal-fired power plants (CFPP) is considered a NORM (Naturally Occurring Radioactive Materials) activity because the coals they burn can present relatively high contents of the naturally occurring radionuclides. In this study, the main radiological impact pathways into the surrounding environments of the four largest coal-fired power plants in Spain were analyzed. These pathways are, first, atmospheric evacuations and wind resuspension and, second, effluent evacuations to nearby rivers or directly to the sea. The atmospheric releases of radionuclides were evaluated by the analyses of soil profiles in the vicinities of the CFPPs. No significant enhancement of radionuclides in the surface soil was observed at the points of maximum deposition of combustion gases, located from 4.3 to 13 km away depending on the considered CFPP. However, an increase of (40)K, (226)Ra, and (232)Th in the surface soils was observed in the first kilometre from the chimney for two CFPPs. This suggested that these radionuclides were released in particulate form. There was also a net influence of the climate in which the CFPPs were located. This was observed in the two CFPPs that were in dry environments, while no increase was observed in the other two, located in more humid environments. The liquid effluents released usually presented an enhancement of dissolved chemical species regarding the initial intake water. Enrichments of the (234,238)U and (226)Ra contents in the water used in the plants' routine procedures were observed, and of (210)Po in the wastewater of just one of the plants. In any case, this enhancement was below the parametric value for the Total Indicative Dose for the hypothetical human consumption of the released waters. As a consequence of these releases of radionuclides, local products destined for human consumption produced in the vicinity of the facilities might incorporate natural radionuclides by these pathways, finding no significant

  11. Natural radionuclides and (137)Cs distributions and their relationship with sedimentological processes in Patras Harbour, Greece.

    PubMed

    Papaefthymiou, H; Papatheodorou, G; Moustakli, A; Christodoulou, D; Geraga, M

    2007-01-01

    Surficial and subsurficial sediment samples derived from gravity cores, selected from the harbour of Patras, Greece, were analyzed for grain size, water content, bulk density, specific gravity, organic carbon content and specific activities of natural radionuclides and (137)Cs. The specific activities of (232)Th, (226)Ra, (40)K and (137)Cs were measured radiometrically. The radionuclides (238)U and (232)Th were also analyzed using the INAA. The differences found between the specific activities of the natural radionuclides measured by the two methods are of no statistical significance. The sediment cores selection was based on a detailed bathymetric and marine seismic survey. Through the study of the detailed bathymetric map and the seismic profiles it was shown that ship traffic is highly influential to the harbour bathymetry. The granulometric and geotechnical properties of the sediments and therefore the specific activities of the natural radionuclides and (137)Cs seem to be controlled by the ship traffic. Relationship between radionuclide activity concentrations and granulometric/geotechnical parameters was defined after the treatment of all the analyses using R-mode factor analysis. The natural radionuclide activities are related to the fine fraction and bulk density of the sediments, while (137)Cs is mainly influenced by the organic carbon content. In addition, (238)U and (226)Ra seem to be in close relation with the heavy minerals fraction in coarse-grained sediments with high specific gravity.

  12. Natural radionuclides and toxic elements in transboundary rivers of Kazakhstan.

    PubMed

    Solodukhin, V; Poznyak, V; Kabirova, G; Stepanov, V; Ryazanova, L; Lennik, S; Liventsova, A; Bychenko, A; Zheltov, D

    2015-06-01

    The paper reports on the study of radionuclide and elemental composition of water, bottom sediment and soil samples collected at the border areas of the following transboundary rivers in Kazakhstan: Chagan, Ural, Ilek, Tobol, Ayat, Irtysh, Emel, Ili, Tekes, Shu, Karabalta, Talas and Syrdarya. The employed analyses include the following methods: instrumental gamma-ray spectrometry, radiochemical analysis, neutron activation analysis, XRF and the inductively coupled plasma mass spectrometry (ICP-MS). Evidence of water environment contamination with radionuclides and toxic elements has been revealed in many of the studied rivers both in Kazakhstan and in adjacent countries. Transboundary transfer of the contaminants is most likely related to local industry (uranium mining and processing) and the presence of radioactive substances in the river basins. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Natural radionuclide concentrations in processed materials from Thai mineral industries.

    PubMed

    Chanyotha, S; Kranrod, C; Chankow, N; Kritsananuwat, R; Sriploy, P; Pangza, K

    2012-11-01

    The naturally occurring radioactive materials (NORMs) distributed in products, by-products and waste produced from Thai mineral industries were investigated. Samples were analysed for radioactivity concentrations of two principal NORM isotopes: (226)Ra and (228)Ra. The enrichment of NORM was found to occur during the treatment process of some minerals. The highest activity of (226)Ra (7 × 10(7) Bq kg(-1)) was in the scale from tantalum processing. The radium concentration in the discarded by-product material from metal ore dressing was also enriched by 3-10 times. Phosphogypsum, a waste produced from the production of phosphate fertilisers, contained 700 times the level of (226)Ra concentration found in phosphate ore. Hence, these residues were also sources of exposure to workers and the public, which needed to be controlled.

  14. A survey of natural terrestrial and airborne radionuclides in moss samples from the peninsular Thailand.

    PubMed

    Wattanavatee, Komrit; Krmar, Miodrag; Bhongsuwan, Tripob

    2017-10-01

    The aim of this study was to determine the activity concentrations of natural terrestrial radionuclides ((238)U, (226)Ra, (232)Th and (40)K) and airborne radionuclides ((210)Pb, (210)Pbex and (7)Be) in natural terrestrial mosses. The collected moss samples (46) representing 17 species were collected from 17 sampling localities in the National Parks and Wildlife Sanctuaries of Thailand, situated in the mountainous areas between the northern and the southern ends of peninsular Thailand (∼7-12 °N, 99-102 °E). Activity concentrations of radionuclides in the samples were measured using a low background gamma spectrometer. The results revealed non-uniform spatial distributions of all the radionuclides in the study area. Principal component analysis and cluster analysis revealed two distinct origins for the studied radionuclides, and furthermore, the Pearson correlations were strong within (226)Ra, (232)Th, (238)U and (40)K as well as within (210)Pb and (210)Pbex, but there was no significant correlation between these two groups. Also (7)Be was uncorrelated to the others, as expected due to different origins of the airborne and terrestrial radionuclides. The radionuclide activities of moss samples varied by moss species, topography, geology, and meteorology of each sampling area. The observed abnormally high concentrations of some radionuclides probably indicate that the concentrations of airborne and terrestrial radionuclides in moss samples were directly related to local geological features of the sampling site, or that high levels of (7)Be were most probably linked with topography and regional NE monsoonal winds from mainland China. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Artificial and natural radionuclides in soils of the southern and middle taiga zones of Komi Republic

    NASA Astrophysics Data System (ADS)

    Beznosikov, V. A.; Lodygin, E. D.; Shuktomova, I. I.

    2017-07-01

    Specific activities of artificial (137Cs, 90Sr) and natural (40K, 232Th, 226Ra) radionuclides in background soils of southern and middle taiga of Komi Republic have been estimated with consideration for the landscape-geochemical features of the territory. It has been shown that their accumulation and migration in soils are determined by the following factors: position in relief, texture, and organic matter content. No anomalous zones with increased contents of radionuclides in soils have been revealed.

  16. Background in the context of land contaminated with naturally occurring radioactive material.

    PubMed

    Read, D; Read, G D; Thorne, M C

    2013-06-01

    The financial implications of choosing a particular threshold for clearance of radioactively contaminated land are substantial, particularly when one considers the volume of naturally occurring radioactive material (NORM) created each year by the production and combustion of fossil fuels and the exploitation of industrial minerals. Inevitably, a compromise needs to be reached between the level of environmental protection sought and the finite resources available for remediation. In the case of natural series radionuclides, any anthropogenic input is always superimposed on the inventory already present in the soil; this 'background' inventory is conventionally disregarded when assessing remediation targets. Unfortunately, the term is not well defined and the concept of 'background dose' is open to alternative interpretations. In this paper, we address the issue of natural background from a geochemical rather than from a solely radiological perspective, illustrating this with an example from the china clay industry. We propose a simple procedure for decision making based on activity concentrations of primordial radionuclides and their progeny. Subsequent calculations of dose need to take into account the mineralogical and chemical characteristics of the contamination, which in the case of NORM are invariably reflected in uranium series disequilibrium.

  17. Naturally occurring and forced azimuthal modes in a turbulent jet

    NASA Technical Reports Server (NTRS)

    Raman, Ganesh; Rice, Edward J.; Reshotko, Eli

    1991-01-01

    Naturally occurring instability modes in an axisymmetric jet are studied utilizing the modal frequency spectrum method. In the early evolution of the jet the axisymmetric mode was predominant, with the azimuthal modes growing quickly but dominating only after the end of the potential core. The growth of the azimuthal modes is seen nearer to the nozzle exit for the jet in the laminar boundary layer case than for the turbulent. Based on the results from these naturally occurring jet instability mode tests, target modes for efficient excitation were determined and two cases of excitation were examined.

  18. Syntheses of naturally occurring terphenyls and related compounds.

    PubMed

    Sawayama, Yusuke; Tsujimoto, Takashi; Sugino, Kumi; Nishikawa, Toshio; Isobe, Minoru; Kawagishi, Hirokazu

    2006-12-01

    Naturally occurring terphenyls and related compounds such as terferol and its corresponding quinone and phlebiarubrone were synthesized from 2,5-diphenyl-1,4-benzoquinone. According to the proposed biosynthetic pathway, chemical conversion of phlebiarubrone to ustalic acid, a toxic compound isolated from the poisonous mushroom, Tricholoma ustale, was examined to find a low-yield conversion to the ustalic acid dimethyl ester.

  19. URBAN STORMWATER TRACING WITH THE NATURALLY OCCURRING DEUTERIUM ISOTOPE

    EPA Science Inventory

    Measurements of the naturally-occurring deuterium isotope assist the tracing of water components during wet-weather flows in an urban watershed. A transect of installations in the vadose and saturated zones was completed in the vicinity of a small stream and storm sewer. High-r...

  20. Naturally occurring fatty acids: Source, chemistry, and uses

    USDA-ARS?s Scientific Manuscript database

    Natural occurring fatty acids are a large and complex class of compounds found in plants and animals. Fatty acids are abundant and of interest because of their renewability, biodegradability, biocompatibility, low cost, and fascinating chemistry. Of the many fatty acids, only 20-25 of them are widel...

  1. Distribution of natural and artificial radionuclides in chernozem soil/crop system from stationary experiments.

    PubMed

    Sarap, Nataša B; Rajačić, Milica M; Đalović, Ivica G; Šeremešić, Srđan I; Đorđević, Aleksandar R; Janković, Marija M; Daković, Marko Z

    2016-09-01

    The present paper focuses on the determination of radiological characteristics of cultivated chernozem soil and crops from long-term field experiments, taking into account the importance of distribution and transfer of radionuclides in the soil-plant system, especially in agricultural cropland. The investigation was performed on the experimental fields where maize, winter wheat, and rapeseed were cultivated. Analysis of radioactivity included determination of the gross alpha and beta activity as a screening method, as well as the activities of the following radionuclides: natural ((210)Pb, (235)U, (238)U, (226)Ra, (232)Th, (40)K, (7)Be) and artificial ((90)Sr and (137)Cs). The activities of natural and artificial ((137)Cs) radionuclides were determined by gamma spectrometry, while the artificial radionuclide (90)Sr was determined by a radiochemical analytical method. Based on the obtained results for the specific activity of (40)K, (137)Cs, and (90)Sr, accumulation factors for these radionuclides were calculated in order to estimate transfer of radionuclides from soil to crops. The results of performed analyses showed that there is no increase of radioactivity that could endanger the food production through the grown crops.

  2. Naturally occurring tumours in the basal metazoan Hydra.

    PubMed

    Domazet-Lošo, Tomislav; Klimovich, Alexander; Anokhin, Boris; Anton-Erxleben, Friederike; Hamm, Mailin J; Lange, Christina; Bosch, Thomas C G

    2014-06-24

    The molecular nature of tumours is well studied in vertebrates, although their evolutionary origin remains unknown. In particular, there is no evidence for naturally occurring tumours in pre-bilaterian animals, such as sponges and cnidarians. This is somewhat surprising given that recent computational studies have predicted that most metazoans might be prone to develop tumours. Here we provide first evidence for naturally occurring tumours in two species of Hydra. Histological, cellular and molecular data reveal that these tumours are transplantable and might originate by differentiation arrest of female gametes. Growth of tumour cells is independent from the cellular environment. Tumour-bearing polyps have significantly reduced fitness. In addition, Hydra tumours show a greatly altered transcriptome that mimics expression shifts in vertebrate cancers. Therefore, this study shows that spontaneous tumours have deep evolutionary roots and that early branching animals may be informative in revealing the fundamental mechanisms of tumorigenesis.

  3. Analysis of Natural and Anthropogenic Radionuclide Content in Palm Date Fruit of the United Arab Emirates: A Baseline Study.

    PubMed

    Rahman, Rubina; Solodov, Alexander

    2016-11-01

    The purpose of this study is to contribute to a wider effort of establishing an environmental radiation baseline for the United Arab Emirates (UAE) before the startup of the country's first nuclear reactor in 2017. An investigation of gamma-emitting radionuclide concentrations in palm dates grown in the UAE was performed. Palm date samples of 10 varieties originating from several local commercial date palm farms of the UAE were collected and analyzed. The study targeted the naturally occurring radionuclides, such as U, Th, and K, in addition to any potential anthropogenic radionuclides, such as Cs and others. Gamma spectrometry revealed measured activity concentrations for U (Ra), Th (Ra), and K that ranged from 0.61 to 0.80 Bq kg, 0.10 to 0.23 Bq kg, and 191 to 362 Bq kg, respectively, on a dry-weight basis, and calculated activity concentrations on a wet basis ranged from 0.52 to 0.69 Bq kg, 0.09 to 0.22 Bq kg, and 168 to 297 Bq kg, respectively. No Cs or other anthropogenic radionuclides could be detected in this study. All measurements were performed using a coaxial HPGe detector with 40% relative efficiency quoted by the manufacturer. Efficiency calibration correction factors were calculated using Angle software.

  4. Radionuclide Migration at the Rio Blanco Site, A Nuclear-stimulated Low-permeability Natural Gas Reservoir

    SciTech Connect

    Clay A. Cooper; Ming Ye; Jenny Chapman; Craig Shirley

    2005-10-01

    The U.S. Department of Energy and its predecessor agencies conducted a program in the 1960s and 1970s that evaluated technology for the nuclear stimulation of low-permeability gas reservoirs. The third and final project in the program, Project Rio Blanco, was conducted in Rio Blanco County, in northwestern Colorado. In this experiment, three 33-kiloton nuclear explosives were simultaneously detonated in a single emplacement well in the Mesaverde Group and Fort Union Formation, at depths of 1,780, 1,899, and 2,039 m below land surface on May 17, 1973. The objective of this work is to estimate lateral distances that tritium released from the detonations may have traveled in the subsurface and evaluate the possible effect of postulated natural-gas development on radionuclide migration. Other radionuclides were considered in the analysis, but the majority occur in relatively immobile forms (such as nuclear melt glass). Of the radionuclides present in the gas phase, tritium dominates in terms of quantity of radioactivity in the long term and contribution to possible whole body exposure. One simulation is performed for {sup 85}Kr, the second most abundant gaseous radionuclide produced after tritium.

  5. Natural radionuclides and plutonium in sediments from the western Arctic Ocean: Sedimentation rates and pathways of radionuclides

    USGS Publications Warehouse

    Huh, C.-A.; Pisias, N.G.; Kelley, J.M.; Maiti, T.C.; Grantz, A.

    1997-01-01

    Sediment cores collected during R.V. Polar Sea AOS94 expedition from the Chukchi Shelf to the North Poke were analyzed for several decay-series natural radionuclides and Pu isotopes to study sedimentation rates and pathways of radionuclides in the western Arctic Ocean. The measured sedimentation rates vary by more than three orders of magnitude along the transect, from 210Pb based rates of 200-700 cm kyr-1 over the Chukchi Shelf and 89 cm kyr-1 at the Chukchi Slope to 230Th-based rates of 0.02-0.3 cm kyr-1 at various settings in the deep basin. 230Th(ex) profiles in the central western Arctic Basin are characterized by a cyclic pattern and a pronounced sub-surface maximum superimposed on an overall decrease with depth. Sediment inventories of excess 210Pb and 230Th in the deep basin as a whole cannot account for their in situ production and 2610Pb fall-out. The opposite is true at the slope and shallower waters. We contend that, as with other ocean basins, boundary scavenging also exists in the Arctic Ocean. The broad continental shelves and the slope region may have the potential of removing all or moat of the particle-reactive radionuclides unaccounted for in the deep basin. The Pu isotope data are consistent with the notion of boundary scavenging. Sediment inventories and concentrations of Pu decrease rapidly offshore. Isotopic composition of Pu suggests mixing of fall-out Pu, which decreases with increasing latitudes, and fuels reprocessing Pu derived from the Russian and Atlantic sides of the Arctic Ocean. Although fuel reprocessing Pu has impinged on the Chukchi Slope, its existence over the Chukchi Shelf is not evident and probably overshadowed by fall-out Pu.

  6. The characteristics of gas hydrates occurring in natural environment

    NASA Astrophysics Data System (ADS)

    Lu, H.; Moudrakovski, I.; Udachin, K.; Enright, G.; Ratcliffe, C.; Ripmeester, J.

    2009-12-01

    In the past few years, extensive analyses have been carried out for characterizing the natural gas hydrate samples from Cascadia, offshore Vancouver Island; Mallik, Mackenzie Delta; Mount Elbert, Alaska North Slope; Nankai Trough, offshore Japan; Japan Sea and offshore India. With the results obtained, it is possible to give a general picture of the characteristics of gas hydrates occurring in natural environment. Gas hydrate can occur in sediments of various types, from sands to clay, although it is preferentially enriched in sediments of certain types, for example coarse sands and fine volcanic ash. Most of the gas hydrates in sediments are invisible, occurring in the pores of the sediments, while some hydrates are visible, appearing as massive, nodular, planar, vein-like forms and occurring around the seafloor, in the fractures related to fault systems, or any other large spaces available in sediments. Although methane is the main component of most of the natural gas hydrates, C2 to C7 hydrocarbons have been recognized in hydrates, sometimes even in significant amounts. Shallow marine gas hydrates have been found generally to contain minor amounts of hydrogen sulfide. Gas hydrate samples with complex gas compositions have been found to have heterogeneous distributions in composition, which might reflect changes in the composition of the available gas in the surrounding environment. Depending on the gas compositions, the structure type of a natural gas hydrate can be structure I, II or H. For structure I methane hydrate, the large cages are almost fully occupied by methane molecules, while the small cages are only partly occupied. Methane hydrates occurring in different environments have been identified with almost the same crystallographic parameters.

  7. Arsenic poisoning in dairy cattle from naturally occurring arsenic pyrites.

    PubMed

    Hopkirk, R G

    1987-10-01

    An outbreak of arsenic poisoning occurred in which most of a 200 cow dairy herd were affected and six died. The source of the arsenic was naturally occurring arsenic pyrites from the Waiotapu Stream, near Rotorua. Arsenic levels in the nearby soil were as high as 6618 ppm. There was little evidence to suggest that treatment affected the course of the disease. Haematology was of little use in diagnosis, post-mortem signs were not always consistent and persistence of the element in the liver appeared short. Control of further outbreaks have been based on practical measures to minimise the intake of contaminated soil and free laying water by the stock.

  8. Addressing Naturally Occurring Asbestos in the Mining Industry

    NASA Astrophysics Data System (ADS)

    Bieber, D. W.

    2012-12-01

    Mining companies deal with naturally occurring asbestos (NOA) issues on their sites in two ways, avoidance and management. Avoidance simply means that to the extent practical, new mines are located in areas where NOA is unlikely to occur. Where mines are located in areas where NOA may be present, mines implement management procedures to identify and control potential sources of NOA. Management practices may include procedures set forth in regulations such as California's Air Toxicity Control Measure that deals with surface mining, voluntary procedures, or a combination of both. The mining industry generally recognizes that addressing NOA issues is a cost of doing business.;

  9. Naturally occurring crystalline phases: analogues for radioactive waste forms

    SciTech Connect

    Haaker, R.F.; Ewing, R.C.

    1981-01-01

    Naturally occurring mineral analogues to crystalline phases that are constituents of crystalline radioactive waste forms provide a basis for comparison by which the long-term stability of these phases may be estimated. The crystal structures and the crystal chemistry of the following natural analogues are presented: baddeleyite, hematite, nepheline; pollucite, scheelite;sodalite, spinel, apatite, monazite, uraninite, hollandite-priderite, perovskite, and zirconolite. For each phase in geochemistry, occurrence, alteration and radiation effects are described. A selected bibliography for each phase is included.

  10. An Update on Antitumor Activity of Naturally Occurring Chalcones

    PubMed Central

    Zhang, En-Hui; Wang, Ru-Feng; Guo, Shu-Zhen; Liu, Bin

    2013-01-01

    Chalcones, which have characteristic 1,3-diaryl-2-propen-1-one skeleton, are mainly produced in roots, rhizomes, heartwood, leaves, and seeds of genera Angelica, Sophora, Glycyrrhiza, Humulus, Scutellaria, Parartocarpus, Ficus, Dorstenia, Morus, Artocarpus, and so forth. They have become of interest in the research and development of natural antitumor agents over the past decades due to their broad range of mechanisms including anti-initiation, induction of apoptosis, antiproliferation, antimetastasis, antiangiogenesis, and so forth. This review summarizes the studies on the antitumor activity of naturally occurring chalcones and their underlying mechanisms in detail during the past decades. PMID:23690855

  11. Synthetic muscle promoters: activities exceeding naturally occurring regulatory sequences

    NASA Technical Reports Server (NTRS)

    Li, X.; Eastman, E. M.; Schwartz, R. J.; Draghia-Akli, R.

    1999-01-01

    Relatively low levels of expression from naturally occurring promoters have limited the use of muscle as a gene therapy target. Myogenic restricted gene promoters display complex organization usually involving combinations of several myogenic regulatory elements. By random assembly of E-box, MEF-2, TEF-1, and SRE sites into synthetic promoter recombinant libraries, and screening of hundreds of individual clones for transcriptional activity in vitro and in vivo, several artificial promoters were isolated whose transcriptional potencies greatly exceed those of natural myogenic and viral gene promoters.

  12. Synthetic muscle promoters: activities exceeding naturally occurring regulatory sequences

    NASA Technical Reports Server (NTRS)

    Li, X.; Eastman, E. M.; Schwartz, R. J.; Draghia-Akli, R.

    1999-01-01

    Relatively low levels of expression from naturally occurring promoters have limited the use of muscle as a gene therapy target. Myogenic restricted gene promoters display complex organization usually involving combinations of several myogenic regulatory elements. By random assembly of E-box, MEF-2, TEF-1, and SRE sites into synthetic promoter recombinant libraries, and screening of hundreds of individual clones for transcriptional activity in vitro and in vivo, several artificial promoters were isolated whose transcriptional potencies greatly exceed those of natural myogenic and viral gene promoters.

  13. Is it necessary to raise awareness about technologically enhanced naturally occurring radioactive materials?

    PubMed

    Michalik, Bogusław

    2009-10-01

    Since radiation risks are usually considered to be related to nuclear energy, the majority of research on radiation protection has focused on artificial radionuclides in radioactive wastes, spent nuclear fuel or global fallout caused by A-bomb tests and nuclear power plant failures. Far less attention has been paid to the radiation risk caused by exposure to ionizing radiation originating from natural radioactivity enhanced due to human activity, despite the fact that technologically enhanced naturally occurring radioactive materials are common in many branches of the non-nuclear industry. They differ significantly from "classical" nuclear materials and usually look like other industrial waste. The derived radiation risk is usually associated with risk caused by other pollutants and can not be controlled by applying rules designed for pure radioactive waste. Existing data have pointed out a strong need to take into account the non-nuclear industry where materials containing enhanced natural radioactivity occur as a special case of radiation risk and enclose them in the frame of the formal control. But up to now there are no reasonable and clear regulations in this matter. As a result, the non-nuclear industries of concern are not aware of problems connected with natural radioactivity or they would expect negative consequences in the case of implementing radiation protection measures. The modification of widely comprehended environmental legislation with requirements taken from radiation protection seems to be the first step to solve this problem and raise awareness about enhanced natural radioactivity for all stakeholders of concern.

  14. Transfer of radionuclides to ants, mosses and lichens in semi-natural ecosystems.

    PubMed

    Dragović, S; Janković Mandić, Lj

    2010-11-01

    There is a scarcity of data on transfer of both natural and anthropogenic radionuclides to detritivorous invertebrates for use in the assessment of radiation exposure. Although mosses and lichens have been extensively used in biomonitoring programs, the data on transfer of radionuclides to these species are limited, particularly for natural radionuclides. To enhance the available data, activity concentrations of (137)Cs, (226)Ra and (228)Ra were measured in ants, mosses and lichens and corresponding undisturbed soil collected from semi-natural ecosystems in Serbia and Montenegro and biota/soil concentration ratios (CR) calculated. Since the majority of internal dose to biota is expected to come from (40)K, the activity concentrations of this radionuclide were also determined. The mean CR values for (137)Cs, (226)Ra and (228)Ra in ants analyzed in this study were found to be 0.02, 0.06 and 0.02, respectively. The mean CR values of radionuclides in mosses were found to be 2.84 for (137)Cs, 0.19 for (226)Ra and 0.16 for (228)Ra, while those in lichens were found to be 1.08 for (137)Cs, 0.15 for (226)Ra and 0.13 for (228)Ra. The CR values obtained in this study were compared with default CR values used in the ERICA Tool database and also with those reported in other studies.

  15. Laboratory migration experiments with radionuclides and natural colloids in a granite fracture

    NASA Astrophysics Data System (ADS)

    Vilks, Peter; Baik, Min-Hoon

    2001-02-01

    Natural colloids in groundwater could facilitate radionuclide transport, provided the colloids are mobile, are present in sufficient concentrations and can adsorb radionuclides. This paper describes the results of a laboratory migration study carried out with combinations of radionuclides and natural colloids within a fracture in a large granite block to experimentally determine the impact of colloids on radionuclide transport. The 85Sr used in this study is an example of a moderately sorbing radionuclide, while the 241Am is typical of a strongly sorbed radionuclide with very low solubility. The natural colloids used in this study were isolated from granite groundwater from Atomic Energy of Canada (AECL) Underground Research Laboratory (URL), and consisted of mostly 1-10 nm organic colloids, along with lesser amounts of 10-450 nm colloids (organics and aluminosilicates). The measured coefficients for radionuclide sorption onto these colloids were between 3×10 2 and 1×10 3 ml/g for 85Sr, and between 7×10 4 and 7×10 5 mg/l for 241Am. The 85Sr sorption on the natural colloids appeared to be reversible. Migration experiments in the granite block were carried out by establishing a flow field between two boreholes (out of a total of nine) intersecting a main horizontal fracture. These experiments showed that dissolved 85Sr behaved as a moderately sorbing tracer, while dissolved 241Am was completely adsorbed by the fracture surfaces and showed no evidence of transport. However, when natural colloids were injected together with dissolved 241Am, a small amount of 241Am transport was observed, demonstrating the ability of natural colloids to facilitate the transport of radionuclides with low solubility. Natural colloids had only a minor effect on the transport of 85Sr. In a separate experiment to test the effect of higher colloid concentrations on 85Sr migration, synthetic colloids were produced from Avonlea bentonite. The introduction of a relatively high concentration

  16. The Natural Occurring Compounds Targeting Endoplasmic Reticulum Stress

    PubMed Central

    Liu, Hai; Yang, Jianqiong; Li, Linfu; Shi, Weimei

    2016-01-01

    ER stress has been implicated in pathophysiological development of many diseases. Persistent overwhelming stimuli trigger ER stress to initiate apoptosis, autophagy, and cell death. IRE1-JNK and eIF2α-CHOP signaling pathways are the two important players of ER stress, which is also modulated by ROS production, calcium disturbance, and inflammatory factors. ER stress has been developed as a novel strategy for diseases management. Recently, a vast of research focuses on the natural occurring compounds targeting ER stress, which results in medical benefits to human diseases. These small reported molecules mainly include polyphenols, alkaloids, and saponins. Many of them have been developed for use in clinical applications. To better understand the pharmacological mechanism of these molecules in ER stress in diseases, efforts have been made to discover and deliver medical merits. In this paper, we will summarize the natural occurring compounds targeting ER stress. PMID:27563337

  17. Naturally Occurring Animal Models with Outer Retina Phenotypes

    PubMed Central

    Baehr, Wolfgang; Frederick, Jeanne M.

    2009-01-01

    Naturally occurring and laboratory generated animal models serve as powerful tools with which to investigate the etiology of human retinal degenerations, especially retinitis pigmentosa (RP), Leber congenital amaurosis (LCA), cone dystrophies (CD) and macular degeneration (MD). Much progress has been made in elucidating gene defects underlying disease, in understanding mechanisms leading to disease, and in designing molecules for translational research and gene-based therapy to interfere with the progression of disease. Key to this progress has been study of naturally occurring murine and canine retinal degeneration mutants. This article will review the history, phenotypes and gene defects of select animal models with outer retina (photoreceptor and retinal pigment epithelium) degeneration phenotypes. PMID:19375447

  18. Mineralogical Characteristics of Carbonate Rock-Hosted Naturally Occurring Asbestos

    NASA Astrophysics Data System (ADS)

    Shin, E.; Roh, Y.

    2012-12-01

    Naturally Occurring Asbestos (NOA) occurs in rocks and soils as a result of natural weathering and human activities. The parent rocks of asbestos have been associated with ultramafic and mafic rocks, and carbonate rock. The previous studies on naturally occurring asbestos were mainly limited to ultramafic and mafic rock-hosted asbestos and studies on carbonate rock-hosted asbestos are relatively rare in South Korea. Therefore, this study was aimed to characterize mineralogy of carbonate rock-hosted NOA at Muju and Jangsu, Jeonbuk province and Seosan and Asan, Chungnam province. The rock types at the four sites are consisting mainly of Precambrian metasedimentary rock. XRD and PLM analyses showed fibrous minerals in the sites were tremolite and actinolite of acicular and columnar forms. SEM-EDS analyses showed that asbestiform tremolite and actinolite had various ratios of length and diameters over 12:1, and needle and columnar forms. A columnar forms of tremolite and actinolite were showed small acicular at the edge of the particle. Its main chemical compositions are mainly Si, O, Mg, Ca, which were identical to tremolite. Actinolite contains Fe in addition to Si, O, Mg, Ca. EPMA analyses of asbestos occurred at Muju indicated that chemical composition are 55% SiO2, 23.2% MgO, 13.1 % CaO, and 0.61 % FeO and the chemical formula calculated as (K0.01Na0.01)Ca2.01(Mg4.94Fe0.05) (Al0.004Si7.98)O22(OH)2, which is close to ideal tremolite. In addition to tremolite, actinolite was also occurred at Seosan, Chungnam. XRD analyses showed that antigorite was existed at Muju, but PLM and SEM analyses showed the antigorite was platy structure, not asbestiform. These results indicate that asbestiform tremolite and actinolite with acicular forms contains in carbonate rocks at Muju and Jangsu, Jeonbuk and Seosan and Asan, Chungnam province South Korea.

  19. Leaching Properties of Naturally Occurring Heavy Metals from Soils

    NASA Astrophysics Data System (ADS)

    Zhang, M.; Hoshino, M.; Yoshikawa, M.; Hara, J.; Sugita, H.

    2014-12-01

    The major threats to human health from heavy metals are associated with exposure to arsenic, lead, cadmium, chromium, mercury, as well as some other elements. The effects of such heavy metals on human health have been extensively studied and reviewed by international organizations such as WHO. Due to their toxicity, heavy metal contaminations have been regulated by national environmental standards in many countries, and/or laws such as the Soil Contamination Countermeasures Act in Japan. Leaching of naturally occurring heavy metals from the soils, especially those around abandoned metal mines into surrounding water systems, either groundwater or surface water systems, is one of the major pathways of exposure. Therefore, understanding the leaching properties of toxic heavy metals from naturally polluted soils is of fundamentally importance for effectively managing abandoned metal mines, excavated rocks discharged from infrastructure constructions such as tunneling, and/or selecting a pertinent countermeasure against pollution when it is necessary. In this study, soil samples taken from the surroundings of abandoned metal mines in different regions in Japan were collected and analyzed. The samples contained multiple heavy metals such as lead, arsenic and chromium. Standard leaching test and sequential leaching test considering different forms of contaminants, such as trivalent and pentavalent arsenics, and trivalent and hexavalent chromiums, together with standard test for evaluating total concentration, X-ray Fluorescence Analysis (XRF), X-ray diffraction analysis (XRD) and Cation Exchange Capacity (CEC) tests were performed. In addition, sequential leaching tests were performed to evaluate long-term leaching properties of lead from representative samples. This presentation introduces the details of the above experimental study, discusses the relationships among leaching properties and chemical and mineral compositions, indicates the difficulties associated with

  20. A novel trauma model: naturally occurring canine trauma.

    PubMed

    Hall, Kelly E; Sharp, Claire R; Adams, Cynthia R; Beilman, Gregory

    2014-01-01

    In human trauma patients, most deaths result from hemorrhage and brain injury, whereas late deaths, although rare, are the result of multiple organ failure and sepsis. A variety of experimental animal models have been developed to investigate the pathophysiology of traumatic injury and evaluate novel interventions. Similar to other experimental models, these trauma models cannot recapitulate conditions of naturally occurring trauma, and therefore therapeutic interventions based on these models are often ineffective. Pet dogs with naturally occurring traumatic injury represent a promising translational model for human trauma that could be used to assess novel therapies. The purpose of this article was to review the naturally occurring canine trauma literature to highlight the similarities between canine and human trauma. The American College of Veterinary Emergency and Critical Care Veterinary Committee on Trauma has initiated the establishment of a national network of veterinary trauma centers to enhance uniform delivery of care to canine trauma patients. In addition, the Spontaneous Trauma in Animals Team, a multidisciplinary, multicenter group of researchers has created a clinical research infrastructure for carrying out large-scale clinical trials in canine trauma patients. Moving forward, these national resources can be utilized to facilitate multicenter prospective studies of canine trauma to evaluate therapies and interventions that have shown promise in experimental animal models, thus closing the critical gap in the translation of knowledge from experimental models to humans and increasing the likelihood of success in phases 1 and 2 human clinical trials.

  1. Naturally Occurring Anthraquinones: Chemistry and Therapeutic Potential in Autoimmune Diabetes

    PubMed Central

    Wu, Yueh-Chen

    2015-01-01

    Anthraquinones are a class of aromatic compounds with a 9,10-dioxoanthracene core. So far, 79 naturally occurring anthraquinones have been identified which include emodin, physcion, cascarin, catenarin, and rhein. A large body of literature has demonstrated that the naturally occurring anthraquinones possess a broad spectrum of bioactivities, such as cathartic, anticancer, anti-inflammatory, antimicrobial, diuretic, vasorelaxing, and phytoestrogen activities, suggesting their possible clinical application in many diseases. Despite the advances that have been made in understanding the chemistry and biology of the anthraquinones in recent years, research into their mechanisms of action and therapeutic potential in autoimmune disorders is still at an early stage. In this paper, we briefly introduce the etiology of autoimmune diabetes, an autoimmune disorder that affects as many as 10 million worldwide, and the role of chemotaxis in autoimmune diabetes. We then outline the chemical structure and biological properties of the naturally occurring anthraquinones and their derivatives with an emphasis on recent findings about their immune regulation. We discuss the structure and activity relationship, mode of action, and therapeutic potential of the anthraquinones in autoimmune diabetes, including a new strategy for the use of the anthraquinones in autoimmune diabetes. PMID:25866536

  2. Natural radionuclides in clay deposits: concentration and dose assessment.

    PubMed

    Khater, Ashraf E M; Al-Mobark, Layla H; Aly, Amany A; Al-Omran, A M

    2013-09-01

    Clays are among the most important industrially used minerals. Three potential clay mineral mining sites in Saudi Arabia were chosen, and 21 clay deposit samples were collected. The activity concentrations (average±standard deviation) of the naturally occurring radioactive materials (NORMs), (238)U, (226)Ra, (232)Th, (228)Ra and (40)K, were 49±20, 47±23, 34±11, 40±20 and 751 Bq kg(-1), respectively. The radiation dose assessments (e.g., absorbed dose rate, nGy h(-1); effective dose equivalent, µSv y(-1); and effective dose rate due to dust inhalation, µSv y(-1)) and hazardous indices (e.g., radium equivalent [Ra-eq] value, external hazardous index [Hex], internal hazardous index [Hin] and representative gamma level [Iγ]) were calculated. The wide variations in the activity concentrations of the NORMs according to sampling region could be due to the origin of the geological formation and the geochemical behaviour of the NORMs. Based on calculated hazardous (external and internal) indices, there were no expected radiological hazardous impacts of using clay deposits as building materials.

  3. Purifying food-grade, naturally occurring CO/sub 2/

    SciTech Connect

    Nobles, J.E.; Stancik, J.W.

    1983-12-26

    Technology to purify naturally occurring CO/sub 2/ into products suitable for enhanced oil recovery (EOR) and food grade CO/sub 2/ markets has been commercially demonstrated in a 20 MMscfd (1,100 ton/day) CO/sub 2/ processing facility owned and operated by Columbia Hydrocarbon Corp. The unit demonstrates that it is technically and economically feasible to process low grade natural gas to produce pipeline specification natural gas, raw CO/sub 2/, and food grade CO/sub 2/. The Selexol treating facility is located on a reclaimed coal strip mine with very restricted plot area. Only compression and dehydration equipment for the CO/sub 2/ is located there. The CO/sub 2/ is transported by pipeline to the Marmet site, approx. 7 miles away. This site contains the facilities for purifying the CO/sub 2/ and for storage.

  4. Study of natural radionuclide and absorbed gamma dose in Ukhimath area of Garhwal Himalaya, India.

    PubMed

    Rautela, B S; Yadav, M; Bourai, A A; Joshi, V; Gusain, G S; Ramola, R C

    2012-11-01

    Natural radiation is the largest contributor to the collective radiation dose of the world population. It is widely distributed in different geological formations such as soil, rocks, air and groundwater. In the present investigation, (226)Ra, (232)Th and (40)K were measured in soil samples of the Ukhimath region of Garhwal Himalaya, India using NaI(Tl) gamma-ray spectrometry. The activity concentrations of naturally occurring radionuclides (226)Ra, (232)Th and (40)K were found to vary from 38.4 ± 6.1 to 141.7 ± 11.9 Bq kg(-1) with an average of 80.5 Bq kg(-1), 57.0 ± 7.5 to 155.9 ± 12.4 Bq kg(-1) with an average of 118.9 Bq kg(-1) and 9.0 ± 3.0 to 672.8 ± 25.9 Bq kg(-1) with an average of 341 Bq kg(-1), respectively. The total absorbed gamma dose rate varies from 70.4 to 169.1 nGy h(-1) with an average of 123.4 nGy h(-1). This study is important to generate a baseline data of radiation exposure in the area. Health hazard effects due to natural radiation exposure are discussed in details.

  5. Natural attenuation of metals and radionuclides: Report from a workshop held by Sandia National Laboratories

    SciTech Connect

    Brady, P.V.; Borns, D.J.

    1997-11-01

    Natural attenuation is increasingly applied to remediate contaminated soils and ground waters. Roughly 25% of Superfund groundwater remedies in 1995 involved some type of monitored natural attenuation, compared to almost none 5 years ago. Remediation by natural attenuation (RNA) requires clear evidence that contaminant levels are decreasing sufficiently over time, a defensible explanation of the attenuation mechanism, long-term monitoring, and a contingency plan at the very least. Although the primary focus of implementation has to date been the biodegradation of organic contaminants, there is a wealth of scientific evidence that natural processes reduce the bioavailability of contaminant metals and radionuclides. Natural attenuation of metals and radionuclides is likely to revolve around sorption, solubility, biologic uptake and dilution controls over contaminant availability. Some of these processes can be applied to actively remediate sites. Others, such as phytoremediation, are likely to be ineffective. RNA of metals and radionuclides is likely to require specialized site characterization to construct contaminant and site-specific conceptual models of contaminant behavior. Ideally, conceptual models should be refined such that contaminant attenuation can be confidently predicted into the future. The technical approach to RNA of metals and radionuclides is explored here.

  6. Natural and anthropogenic radionuclides in the granitic region of Kapidag peninsula, Western Anatolia, Turkey.

    PubMed

    Kapdan, E; Varinlioglu, A; Karahan, G; Taskin, H; Okka, M; Kiziltas, S; Karahan, S

    2012-07-01

    Naturally occurring radionuclides of terrestrial origin (also called primordial radionuclides) are present in various degrees in all media in the environment. This study represents the reports on the natural and anthropogenic radionuclides in the Kapidag granitic region. For this purpose, activities of radionuclides in soil, beach sands and rocks of the region have been investigated to assess the radiological hazard of the natural radioactivity. The radium equivalent activities, the absorbed dose rates and the external hazard indexes have been calculated, and also in situ gamma dose rates have been measured in the region. The mean activities of (238)U, (232)Th and (40)K with the ranges were determined as 31.1±15.7 (12.1-71.9), 42.5±15.9 (19.7-94.9), 590.3±192.2 (184.7-892.5), in the soil, as 16.5±9.5 (4.9-40.8), 67.1±106.9 (18.5-433.0), 569.2±212.6 (162.0-821.1) in the sand and as 25.4±12.8 (4.8-50.7), 37.8±21.5 (4.5-96.7), and 592.4±285.5 (62.4-1121.6) Bq kg(-1) in the rocks, respectively. It was also observed that the average activities of (137)Cs were ranged 0-27.8 Bq kg(-1) in the soil and 0.6-3.8 Bq kg(-1) in the beach sands. The mean Ra(eq) activities of the rocks, sands and soil were found to be 125.1±59.5, 156.3±157.2 and 137.3±48.8 Bq kg(-1), respectively, lower than the recommended maximum value of 370 Bq kg(-1) with some exceptions. The maximum contributors to the total absorbed gamma dose rates in air were determined as (238)U (45%) for the beach sands, (238)U (40%) for the soil and (40)K (41%) for rocks. The average outdoor gamma dose rates for the soil due to terrestrial and cosmic radiations were found to be 64.6±22.7 and 47.1±9.6 nGy h(-1), respectively, with the total of 111.7±29.5 nGy h(-1) outdoor gamma exposure rate and the annual average effective outdoor gamma dose was calculated as 137±36.2 µSv for the region. The results of the study were discussed with similar studies in close regions and the worldwide averages.

  7. Characterization of contaminant transport using naturally-occurring U-series disequilibria. 1998 annual progress report

    SciTech Connect

    Murrell, M.; Ku, T.L.

    1998-06-01

    'The goal of the research is to study the migratory behavior of contaminants in subsurface fractured systems using naturally occurring uranium- and thorium-series radionuclides as tracers under in-situ physico-chemical and hydrogeologic conditions. Naturally occurring U- and Th-series disequilibria can provide information on the rates of adsorption-desorption and transport of contaminants as well as on fluid transport and rock dissolution in a natural setting. The authors are developing a realistic model of contaminant migration in the Snake River Plain Aquifer beneath the INEEL by evaluating the retardation processes involved in the rock/water interaction. The major tasks are to: (1) determine the natural distribution of U, Th, Pa and Ra isotopes in the groundwater as well as in rock minerals and sorbed phases, and (2) study rock/water interaction processes using U/Th series disequilibria and a statistical analysis-based model code for the calculation of in-situ retardation factors of radionuclides and rock/water interaction time scales. This study will also provide an improved understanding of the hydrogeologic features of the site and their impact on the migration of contaminants. This report summarizes results after 20 months of a 36-month project. Studies performed at LANL include analysis of the long-lived nuclides {sup 238}U, {sup 235}U, {sup 234}U, {sup 230}Th, {sup 226}Ra, {sup 232}Th, and {sup 231}Pa by thermal ionization mass spectrometry (TIMS). Studies performed at the Univ. of Southern California include the measurement of short-lived naturally occurring radionuclides by decay-counting techniques and the development of models to predict the migration behavior of these radionuclides. Initial efforts began with analysis of 31, 0.5L water samples obtained through routine sampling by USGS and INEEL personnel. One significant observation from these data is that {sup 234}U/{sup 238}U activity ratios are highest in waters that emanate from local recharge

  8. Gamma-emitting natural and anthropogenic radionuclides in the terrestrial environment of Kongsfjord, Svalbard.

    PubMed

    Dowdall, M; Gerland, S; Lind, B

    2003-04-15

    This paper presents results obtained from a radiometric survey, conducted by the Norwegian Radiation Protection Authority, into the levels of gamma-emitting radionuclides, both anthropogenic and natural, in the terrestrial environment of Kongsfjorden, which lies on the North-Western Coast of Spitsbergen in the Arctic archipelago of Svalbard (79 degrees N, 12 degrees E). Samples of terrestrial matrices were taken during field campaigns conducted between 2000 and 2002 and analysed for a range of gamma-emitting radionuclides. The objectives of this study included an assessment of the levels of gamma-emitting radionuclides in the terrestrial environment of the region, identification of processes and activities that influence the accumulation and redistribution of such nuclides within the region and elucidation of the behaviour of such radionuclides within a high arctic environment. Results indicate a quite homogenous spatial distribution of such radionuclides within the study area and highlight the relatively low levels of contamination by the anthropogenic radionuclide, 137Cs, on Svalbard. Average values and ranges of the radionuclides activities in surface soils (0-3 cm) were: 238U 42 Bq/kg (17-134), 226Ra 43 Bq/kg (12-137), 232Th 21 Bq/kg (4-52), 40K 283 Bq/kg (31-564), 137Cs 35 Bq/kg (1-146). Average levels of these nuclides in avian faecal materials were 238U 63 Bq/kg, 226Ra 54 Bq/kg, 232Th 19 Bq/kg, 40K 365 Bq/kg, 137Cs 78 Bq/kg. Enrichment of radionuclides is apparent in soils taken from locations close to bird colonies in the locale, maximum levels of the radionuclides being found in samples associated with such colonies. The results indicate that this is due to concentration of such radionuclides within the faecal material of the birds and subsequent enrichment of the nearby soils either via direct incorporation of the faeces into the soil or by leaching processes. The results indicate that this process may result in contamination of non-related species, such

  9. Hemostatic abnormalities in dogs with naturally occurring heatstroke.

    PubMed

    Bruchim, Yaron; Kelmer, Efrat; Cohen, Adar; Codner, Carolina; Segev, Gilad; Aroch, Itamar

    2017-05-01

    To investigate hemostatic analyte abnormalities and their association with mortality in dogs with naturally occurring heatstroke. Prospective observational study. University teaching hospital. Thirty client-owned dogs with naturally occurring heatstroke. None. Citrated and EDTA blood samples were collected at presentation and at 4, 12, 24, 36, and 48 hours postpresentation (PP). Hemostatic tests performed included platelet count, prothrombin and activated partial thromboplastin times (PT and aPTT, respectively), antithrombin activity (ATA), total protein C activity (tPCA), fibrinogen, and D-dimer concentrations. The overall survival rate was 60% (18/30 dogs). Older age, higher heart rate and rectal temperature at presentation, and time from onset of clinical signs to presentation were significantly associated with mortality. Hemostatic analytes at presentation were not associated with mortality. Prolonged PT and aPTT at 12-24 hours PP, lower tPCA at 12 hours PP, and hypofibrinogenemia at 24 hours PP were significantly (P < 0.05) associated with mortality. Increased D-dimer concentration and low ATA were common at all time points, but were not associated with mortality. The frequency of disseminated intravascular coagulation (DIC) increased in nonsurvivors throughout hospitalization, but the development of DIC was not associated with mortality. The number of abnormal coagulation disturbances during the first 24 hours was significantly higher in nonsurvivors (P = 0.04). Hemostatic derangements are common in dogs with naturally occurring heatstroke. Alterations in PT, aPTT, tPCA, and fibrinogen concentrations appear to be associated with the outcome at 12-24 hours PP, exemplifying the need for serial measurement of multiple laboratory hemostatic tests during hospitalization, even when within reference interval on presentation. The development of DIC, as defined in this cohort, was not associated with mortality; however, nonsurvivors had significantly more coagulation

  10. Issues related to regulatory control of naturally occurring radioactive materials

    SciTech Connect

    Chen, S.Y.

    1997-04-01

    Nearly 80% of human radiation exposure is from naturally occurring radioactive materials (NORM). While exposure from man-made sources of radiation has been well regulated, no consistent regulatory controls exist for NORM. Because elevated radiation levels have resulted from NORM enhancement activities such as occur in the petroleum, fertilizer, mining, and processing industries, some form of regulatory control is in order. In the US, regulation of NORM by federal agencies such as the Nuclear Regulatory Commission or the Environmental Protection Agency is not anticipated in the near future because there are no authorizing federal statutes. Important issues for addressing the control of NORM include source characterization and generation, radiation protection concerns, waste management and disposition, and the regulatory framework.

  11. Analytical evaluation of natural radionuclides and their radioactive equilibrium in raw materials and by-products.

    PubMed

    Ji, Young-Yong; Chung, Kun Ho; Lim, Jong-Myoung; Kim, Chang-Jong; Jang, Mee; Kang, Mun Ja; Park, Sang Tae

    2015-03-01

    An investigation into the distribution of natural radionuclides and radioactive secular equilibrium in raw materials and by-products in a domestic distribution was conducted to deduce the optimum conditions for the analytical evaluation of natural radionuclides for (238)U, (226)Ra, and (232)Th using a gamma-ray spectrometer and inductively coupled plasma mass spectrometer (ICP-MS). The range of the specific activities of natural radionuclides was first evaluated by analyzing (228)Ac and (214)Bi, which are (232)Th and (226)Ra indicators, respectively, in about 100 samples of raw materials and by-products through a gamma-ray spectrometer. From further experiments using several samples selected based on the results of the distribution of natural radionuclides, the validation of their analytical evaluations for the indirect measurements using a gamma-ray spectrometer and direct measurements using ICP-MS was assured by comparing their results. Chemically processed products from the raw materials, such as Zr sand and ceramic balls, were generally shown for the type of bead and particularly analyzed showing a definite disequilibrium with above a 50% difference between (238)U and (226)Ra in the uranium series and (232)Th and (228)Ra in the thorium series.

  12. Temporal Sequencing of Brain Activations During Naturally Occurring Thermoregulatory Events

    PubMed Central

    Diwadkar, Vaibhav A.; Murphy, Eric R.; Freedman, Robert R.

    2014-01-01

    Thermoregulatory events are associated with activity in the constituents of the spinothalamic tract. Whereas studies have assessed activity within constituents of this pathway, in vivo functional magnetic resonance imaging (fMRI) studies have not determined if neuronal activity in the constituents of the tract is temporally ordered. Ordered activity would be expected in naturally occurring thermal events, such as menopausal hot flashes (HFs), which occur in physiological sequence. The origins of HFs may lie in brainstem structures where neuronal activity may occur earlier than in interoceptive centers, such as the insula and the prefrontal cortex. To study such time ordering, we conducted blood oxygen level-dependent-based fMRI in a group of postmenopausal women to measure neuronal activity in the brainstem, insula, and prefrontal cortex around the onset of an HF (detected using synchronously acquired skin conductance responses). Rise in brainstem activity occurred before the detectable onset of an HF. Activity in the insular and prefrontal trailed that in the brainstem, appearing following the onset of the HF. Additional activations associated with HF's were observed in the anterior cingulate cortex and the basal ganglia. Pre-HF brainstem responses may reflect the functional origins of internal thermoregulatory events. By comparison insular, prefrontal and striatal activity may be associated with the phenomenological correlates of HFs. PMID:23787950

  13. Transmission of Naturally Occurring Lymphoma in Macaque Monkeys

    NASA Astrophysics Data System (ADS)

    Hunt, Ronald D.; Blake, Beverly J.; Chalifoux, Laura V.; Sehgal, Prabhat K.; King, Norval W.; Letvin, Norman L.

    1983-08-01

    Spontaneously occurring rhesus monkey lymphomas were transmitted into healthy rhesus monkeys by using tumor cell suspensions. The naturally arising tumors included an immunoblastic sarcoma and an undifferentiated lymphoma. Recipient animals developed undifferentiated lymphomas, poorly differentiated lymphomas, or parenchymal lymphoproliferative abnormalities suggestive of early lesions of lymphoma. Some of these animals developed such opportunistic infections as cytomegalovirus hepatitis and cryptosporidiosis. They also showed evidence of an abnormal circulating peripheral blood mononuclear cell. These findings, all characteristic of the acquired immune deficiency syndrome (AIDS) of macaques, suggest a link between these transmissible lymphomas and AIDS in macaque monkeys.

  14. Naturally occurring anti-tissue antibodies in rat sera

    PubMed Central

    Weir, D. M.; Pinckard, R. N.; Elson, C. J.; Suckling, Deirdre E.

    1966-01-01

    Seventy per cent of normal rat sera have been shown to contain heat labile serum component(s) active against various rat organ homogenates as demonstrated by haemolytic complement fixation and passive haemagglutination tests. The main antigenic activity in rat liver has been found in the mitochondrial fractions. It was also demonstrated by the indirect fluorescent antibody technique that both guinea-pig complement and high molecular weight rat globulins were fixed to rat organ sections. Chemotactic activity has also been observed with rat serum and rat liver mitochondria and it is suggested that these naturally occurring antibodies may be implicated in the removal of tissue breakdown products. PMID:5338951

  15. Transmission of naturally occurring lymphoma in macaque monkeys.

    PubMed Central

    Hunt, R D; Blake, B J; Chalifoux, L V; Sehgal, P K; King, N W; Letvin, N L

    1983-01-01

    Spontaneously occurring rhesus monkey lymphomas were transmitted into healthy rhesus monkeys by using tumor cell suspensions. The naturally arising tumors included an immunoblastic sarcoma and an undifferentiated lymphoma. Recipient animals developed undifferentiated lymphomas, poorly differentiated lymphomas, or parenchymal lymphoproliferative abnormalities suggestive of early lesions of lymphoma. Some of these animals developed such opportunistic infections as cytomegalovirus hepatitis and cryptosporidiosis. They also showed evidence of an abnormal circulating peripheral blood mononuclear cell. These findings, all characteristic of the acquired immune deficiency syndrome (AIDS) of macaques, suggest a link between these transmissible lymphomas and AIDS in macaque monkeys. Images PMID:6576377

  16. On incompressibility of a matrix in naturally occurring composites

    NASA Astrophysics Data System (ADS)

    Gorbatikh, Larissa; Pingle, Pawan

    2007-12-01

    The work illustrates that a soft matrix, which has the Poisson ratio close to 0.5 and is reinforced with a rigid-line inclusion, possesses an interesting behavior at the inclusion/matrix interface. It experiences a hydrostatic stress state and behaves as an incompressible fluid under longitudinal and transverse loads. The stress singularities are eliminated ahead of the inclusion tips, and when interface defects are formed, their effect on the composite compliance is minimal. These observations have far reaching applications when one is interested in mechanisms of multifunctional property improvement of composites (such as toughness and stiffness) learned from naturally occurring composites.

  17. Thermoradiation inactivation of naturally occurring organisms in soil

    NASA Technical Reports Server (NTRS)

    Reynolds, M. C.; Lindell, K. F.; David, T. J.

    1973-01-01

    Samples of soil collected from Kennedy Space Center near spacecraft assembly facilities were found to contain microorganisms very resistant to conventional sterilization techniques. The inactivation behavior of the naturally occurring spores in soil was investigated using dry heat and ionizing radiation, first separately, then in combination. Dry heat inactivation rates of spores were determined for 105 and 125 C. Radiation inactivation rates were determined for dose rates of 660 and 76 krad/hr at 25 C. Simultaneous combinations of heat and radiation were then investigated at 105, 110, 115, 120, and 125 C. Combined treatment was found to be highly synergistic requiring greatly reduced radiation doses to accomplish sterilization.

  18. Immunomodulatory effects in workers exposed to naturally occurring asbestos fibers.

    PubMed

    Ledda, Caterina; Costa, Chiara; Matera, Serena; Puglisi, Beatrice; Costanzo, Valentina; Bracci, Massimo; Fenga, Concettina; Rapisarda, Venerando; Loreto, Carla

    2017-05-01

    Natural asbestiform fibers are defined 'naturally occurring asbestos' (NOA) and refer to the mineral as a natural component of soils or rocks. The release of NOA fibers into the air from rocks or soils by routine human activities or natural weathering processes represents a risk for human beings. Fluoro-edenite (FE) is a NOA fiber detected in the benmoreitic lava in the area of Biancavilla, South-west slope of Mt. Etna. The aim of the present study was to investigate FE immunotoxicity pathways in a group of 38 occupationally exposed construction workers, in order to find any biological markers of its effect. Subjects underwent respiratory function tests and HRCT total chest scanning. Serum IL-1β, IL-6, IL-8 and TNF-α were measured. The presence of PPs was significantly greater in subjects exposed than in the control (25 vs. 2). In subjects exposed to FE, IL-1β and TNF-α values were significantly higher than the controls. The previously observed increase of IL-1β and IL-18 showed a probable involvement of the proteic complex defined inflammosome by FE fibers.

  19. Antitumor effects of naturally occurring oligomeric resveratrol derivatives.

    PubMed

    Qiao, Haishi; Chen, Xiaoqing; Xu, Lanfang; Wang, Jingjing; Zhao, Guoyan; Hou, Yayi; Ge, Hui Ming; Tan, Ren-Xiang; Li, Erguang

    2013-11-01

    This study was designed to evaluate and characterize the molecular basis of antitumor activity of naturally occurring resveratrol (RES; 3,5,4'-trihydroxy-trans-stilbene) derivatives. The compounds were isolated from plants in previous studies and characterized spectroscopically. The antitumor activities of 31 RES derivatives, including dimers, trimers, and tetramers of RES, were evaluated using cell-based assays and validated on a murine model. Several trimeric and a tetrameric stilbenoids induced tumor cell apoptosis or growth arrest of several tumor cell lines with IC50 values (2.8-19.7 μM), significantly lower than that of RES (IC50>70 μM). Using pauciflorol B (PauB) as an example, we showed that the compound induced apoptosis p53 dependently, inducing p53 accumulation and p53-modulated gene expression in cells with wild-type p53, but not in those with nonfunctional p53. Reexpression of p53 in p53-null cells rescued cell death response. In parallel, the MAPK/p38 was activated and critical for PauB-induced killing. Interestingly, activation of p38 in p53 deficient cells was sufficient to drive cells into senescence via the p16-pRb pathway. Finally, PauB dose-dependently inhibited tumor growth on nude mice. Naturally occurring trimeric and tetrameric stilbenoids are potent antitumor agents. Those compounds exert antitumor effect through p53-dependent induction of apoptosis or senescence.

  20. Daily intakes of naturally occurring radioisotopes in typical Korean foods.

    PubMed

    Choi, Min-Seok; Lin, Xiu-Jing; Lee, Sun Ah; Kim, Wan; Kang, Hee-Dong; Doh, Sih-Hong; Kim, Do-Sung; Lee, Dong-Myung

    2008-08-01

    The concentrations of naturally occurring radioisotopes ((232)Th, (228)Th, (230)Th, (228)Ra, (226)Ra, and (40)K) in typical Korean foods were evaluated. The daily intakes of these radioisotopes were calculated by comparing concentrations in typical Korean foods and the daily consumption rates of these foods. Daily intakes were as follows: (232)Th, 0.00-0.23; (228)Th, 0.00-2.04; (230)Th, 0.00-0.26; (228)Ra, 0.02-2.73; (226)Ra, 0.01-4.37 mBq/day; and (40)K, 0.01-5.71 Bq/day. The total daily intake of the naturally occurring radioisotopes measured in this study from food was 39.46 Bq/day. The total annual internal dose resulting from ingestion of radioisotopes in food was 109.83 muSv/y, and the radioisotope with the highest daily intake was (40)K. These values were same level compiled in other countries.

  1. Macaques Exhibit a Naturally-Occurring Depression Similar to Humans

    PubMed Central

    Xu, Fan; Wu, Qingyuan; Xie, Liang; Gong, Wei; Zhang, Jianguo; Zheng, Peng; Zhou, Qinmin; Ji, Yongjia; Wang, Tao; Li, Xin; Fang, Liang; Li, Qi; Yang, Deyu; Li, Juan; Melgiri, Narayan D.; Shively, Carol; Xie, Peng

    2015-01-01

    Rodent models have dominated preclinical investigations into the mechanisms of depression. However, these models-which rely on subjecting individual rodents to physical stressors - do not realistically resemble the etiopathological development of depression, which occurs naturally in a social context. A non-human primate model that better reflects the social ethological aspects of depression would be more advantageous to investigating pathophysiological mechanisms and developing antidepressant therapeutics. Here, we describe and model a naturally-occurring depressive state in a non-human primate species, the cynomolgus monkey (Macaca fascicularis), in a realistic social ethological context and associate the depressed behavioral phenotype with significant serum metabolic perturbations. One to two subjects per stable social colony (17–22 subjects) manifested a depressive phenotype that may be attributed to psychosocial stress. In accordance with rodent and human studies, the serum metabolic phenotype of depressed and healthy subjects significantly differed, supporting the model's face validity. However, application of the fast-acting antidepressant ketamine failed to demonstrate predictive validity. This study proposes a non-human primate depression model in a realistic social ethological context that can better approximate the psychosocial stressors underlying depression. PMID:25783476

  2. Exploring naturally occurring ivy nanoparticles as an alternative biomaterial.

    PubMed

    Huang, Yujian; Wang, Yi-Jun; Wang, Yongzhong; Yi, Sijia; Fan, Zhen; Sun, Leming; Lin, Derrick; Anreddy, Nagaraju; Zhu, Hua; Schmidt, Michael; Chen, Zhe-Sheng; Zhang, Mingjun

    2015-10-01

    Arabinoglactan protein (AGP)-rich nanoparticles obtained from the sticky exudates of Hedera helix (English ivy), have shown promising potential to be used in nanomedicine owing to their excellent aqueous solubility, low intrinsic viscosity, biocompatibility, and biodegradability. In this study, the feasibilities of utilizing ivy nanoparticles (INPs) as nano-carriers for delivering chemotherapeutic drugs in cancer therapy and as nano-fillers to develop novel scaffolds for tissue engineering in regenerative medicine are evaluated. Via electrostatic and hydrophobic interactions, pH-responsive nanoconjugates are formed between the INPs and the doxorubicin (DOX) with an entrapment ratio of 77.9±3.9%. While the INPs show minimal cytotoxicity, the formed INP-DOX conjugates exhibit substantially stronger cytotoxic activity than free DOX against multiple cancer cell lines, suggesting a synergistic effect is established upon conjugation. The anti-cancer effects of the INP-DOX conjugates are further evaluated via in vivo xenograft assays by subcutaneously implanting DOX resistant cell line, SW620/Ad-300, into nude mice. The tumor volumes in mice treated with the INP-DOX conjugates are significantly less than those of the mice treated with free DOX. In addition, the INPs are further exploited as nano-fillers to develop fibrous scaffolds with collagen, via mimicking the porous matrix where the INPs are embedded under natural condition. Enhanced adhesion of smooth muscle cells (SMCs) and accelerated proliferation of mouse aortic SMCs are observed in this newly constructed scaffold. Overall, the results obtained from the present study suggest great potential of the INPs to be used as biocompatible nanomaterials in nanomedicine. The AGP-rich INP renders a glycoprotein architecture that is amenable for modification according to the functional designs, capable of being developed as versatile nanomaterials for extensive biomedical applications. Naturally occurring organic

  3. Naturally occurring animal models of human hepatitis E virus infection.

    PubMed

    Yugo, Danielle M; Cossaboom, Caitlin M; Meng, Xiang-Jin

    2014-01-01

    Hepatitis E virus (HEV) is a single-stranded, positive-sense RNA virus in the family Hepeviridae. Hepatitis E caused by HEV is a clinically important global disease. There are currently four well-characterized genotypes of HEV in mammalian species, although numerous novel strains of HEV likely belonging to either new genotypes or species have recently been identified from several other animal species. HEV genotypes 1 and 2 are limited to infection in humans, whereas genotypes 3 and 4 infect an expanding host range of animal species and are zoonotic to humans. Historical animal models include various species of nonhuman primates, which have been indispensable for the discovery of human HEV and for understanding its pathogenesis and course of infection. With the genetic identification and characterization of animal strains of HEV, a number of naturally occurring animal models such as swine, chicken, and rabbit have recently been developed for various aspects of HEV research, including vaccine trials, pathogenicity, cross-species infection, mechanism of virus replication, and molecular biology studies. Unfortunately, the current available animal models for HEV are still inadequate for certain aspects of HEV research. For instance, an animal model is still lacking to study the underlying mechanism of severe and fulminant hepatitis E during pregnancy. Also, an animal model that can mimic chronic HEV infection is critically needed to study the mechanism leading to chronicity in immunocompromised individuals. Genetic identification of additional novel animal strains of HEV may lead to the development of better naturally occurring animal models for HEV. This article reviews the current understanding of animal models of HEV infection in both natural and experimental infection settings and identifies key research needs and limitations. © The Author 2014. Published by Oxford University Press on behalf of the Institute for Laboratory Animal Research. All rights reserved. For

  4. Composition and structural aspects of naturally occurring ferrihydrite

    NASA Astrophysics Data System (ADS)

    Cismasu, A. Cristina; Michel, F. Marc; Tcaciuc, A. Patricia; Tyliszczak, Tolek; Brown, Gordon E., Jr.

    2011-02-01

    A series of naturally occurring ferrihydrites sampled from an acid mine drainage environment were characterized and compared with synthetic 2-line ferrihydrite using high energy X-ray total scattering and pair distribution function analysis, Scanning Transmission X-ray Microscopy (STXM), Transmission Electron Microscopy (TEM), BET N 2 surface area measurements, and chemical extractions in order to place constraints on their structural and physical properties as a function of composition. Overall, the short- and intermediate-range ordering of the natural samples is comparable to synthetic ferrihydrite. However, with increasing Al, Si, and organic matter contents, a decrease in particle size and an increase in structural disorder were observed. Silica is suspected to have a pronounced effect on the crystallinity of ferrihydrite as a result of its inhibitory effect on Fe polymerization and particle growth, and it is likely complexed at the surfaces of ferrihydrite nanoparticles. Aluminum, on the other hand may substitute for Fe 3+ in natural ferrihydrite. Organic matter is pervasive and intimately associated with ferrihydrite aggregates, and its presence during ferrihydrite precipitation may have contributed to additional structural disorder. The increase in impurity content affects not only the particle size and structural order of ferrihydrite but may also have a significant effect on its surface reactivity.

  5. Is anyone regulating naturally occurring radioactive material? A state survey

    SciTech Connect

    Gross, E.M.; Barisas, S.G.

    1993-08-01

    As far as we know, naturally occurring radioactive material (NORM) has surrounded humankind since the beginning of time. However, recent data demonstrating that certain activities concentrate NORM have increased concern regarding its proper handling and disposal and precipitated the development of new NORM-related regulations. The regulation of NORM affects the management of government facilities as well as a broad range of industrial processes. Recognizing that NORM regulation at the federal level is extremely limited, Argonne National Laboratory (ANL) conducted a 50-state survey to determine the extent to which states have assumed the responsibility for regulating NORM as well as the NORM standards that are currently being applied at the state level. Though the survey indicates that NORM regulation comprises a broad spectrum of controls from full licensing requirements to virtually no regulation at afl, a trend is emerging toward recognition of the need for increased regulation of potential NORM hazards, particularly in the absence of federal standards.

  6. Antibacterial mesh: a novel technique involving naturally occurring cellular proteins.

    PubMed

    Yurko, Yuliya; McDeavitt, Kathleen; Kumar, Rohan Satish; Martin, Terri; Prabhu, Ajita; Lincourt, Amy E; Vertegel, Alexey; Heniford, B Todd

    2012-03-01

    Naturally occurring antimicrobial peptides are possibly the "next frontier" in infection prevention. Binding them to mesh could reduce the rate of mesh infections. This study identifies an antimicrobial agent capable of significant antibacterial activity when bound to mesh. Lysozyme, human beta defensin (HBD-3), human cathelicidin (LL-37), and lysostaphin were adsorbed to polypropylene mesh at various concentrations. Treated meshes were placed in a suspension of 1 × 10(6) Staphylococcus aureus. Antibacterial action was monitored by turbidimetric assay, fluorescent imaging, and a colony counting method. A very high rate of lysis of S aureus cells was observed in the lysostaphin-treated group as measured by optical density; none survived as seen on colony count assays. Optical density for mesh coated with lysozyme, HBD-3, and LL-37 did not differ from untreated controls, with 100% survival rates by colony counts. Lysostaphin had superior antibacterial activity following adsorption to mesh.

  7. Additive CHARMM force field for naturally occurring modified ribonucleotides

    PubMed Central

    Xu, You; Vanommeslaeghe, Kenno; Aleksandrov, Alexey; MacKerell, Alexander D.

    2016-01-01

    More than 100 naturally occurring modified nucleotides have been found in RNA molecules, in particular in tRNAs. We have determined molecular mechanics force field parameters compatible with the CHARMM36 all‐atom additive force field for all these modifications using the CHARMM force field parametrization strategy. Emphasis was placed on fine tuning of the partial atomic charges and torsion angle parameters. Quantum mechanics calculations on model compounds provided the initial set of target data, and extensive molecular dynamics simulations of nucleotides and oligonucleotides in aqueous solutions were used for further refinement against experimental data. The presented parameters will allow for computational studies of a wide range of RNAs containing modified nucleotides, including the ribosome and transfer RNAs. © 2016 The Authors. Journal of Computational Chemistry Published by Wiley Periodicals, Inc. PMID:26841080

  8. Naturally occurring B-cell autoreactivity: a critical overview.

    PubMed

    Avrameas, Stratis; Ternynck, Therese; Tsonis, Ioannis A; Lymberi, Peggy

    2007-12-01

    In over one century of research in immunology marked progress in the scientific knowledge and the implications derived from it has been made. At the same time several contradictory and seemingly opposing results have been obtained. The term autoimmunity is still conceived by many as a term directly related to an immunopathological state. However, strong evidence exist that not only the immune system is able to recognize self-constituents, but it appears also that this property is essential for homeostasis. Direct or indirect alterations of such self-recognition properties of the immune system may contribute to pathology. In this review, the most recent advances in the field of naturally occurring B-cell autoreactivity in health as well as in disease are presented and discussed.

  9. Additive CHARMM force field for naturally occurring modified ribonucleotides.

    PubMed

    Xu, You; Vanommeslaeghe, Kenno; Aleksandrov, Alexey; MacKerell, Alexander D; Nilsson, Lennart

    2016-04-15

    More than 100 naturally occurring modified nucleotides have been found in RNA molecules, in particular in tRNAs. We have determined molecular mechanics force field parameters compatible with the CHARMM36 all-atom additive force field for all these modifications using the CHARMM force field parametrization strategy. Emphasis was placed on fine tuning of the partial atomic charges and torsion angle parameters. Quantum mechanics calculations on model compounds provided the initial set of target data, and extensive molecular dynamics simulations of nucleotides and oligonucleotides in aqueous solutions were used for further refinement against experimental data. The presented parameters will allow for computational studies of a wide range of RNAs containing modified nucleotides, including the ribosome and transfer RNAs.

  10. Processing and disposal of scales containing naturally occurring radioactive materials

    SciTech Connect

    Chambers, D.G.; Woods, S.E.; Abernathy, S.E.

    1994-12-31

    Since the discovery that many drill cuttings, scales, sludges, and platings contain elevated amounts of Naturally Occurring Radioactive Material (NORM), many companies and regulating authorities have wondered what is the best method for disposing of this material. This paper covers a process which grinds and slurries this material to a form acceptable for injection to a well. The process consists of (1) classification of material, (2) bulk breakdown, and (3) grinding and slurrying to a consistency which keeps the particles suspended in solution until time for well injection. Well injection takes the form of encapsulation by cementing the well casing below and above the injected NORM during a plug and abandonment operation. In conclusion, the philosophy of the process is to take the NORM generated through the exploration and production of oil and gas and place it back into the reservoir from which it came. This technique is one which protects the environment from the possible hazards associated with mismanaged NORM.

  11. Leucocyte function in rats with naturally occurring gingivitis.

    PubMed

    Ohura, K; Shinohara, M; Ogata, K; Nishiyama, A; Mori, M

    1990-01-01

    The severity of gingivitis in relation to abnormal macrophage chemotaxis and superoxide (O2-) production was investigated in rats with naturally occurring gingivitis (plaque-susceptible rats). Macrophage chemotaxis was measured by the membrane filter method; zymosan-activated serum was used as a chemo-attractant. O2- production was measured by the reduction of cytochrome c method. Opsonized zymosan, phorbol myristate acetate and calcium ionophore A23187 were used as stimulants. The macrophage chemotaxis and O2- production in the plaque-susceptible rats with deep pockets were significantly lower than those in the susceptible rats with shallow pockets or the normal group. In addition, there was a negative correlation between the severity of gingivitis in plaque-susceptible rats and macrophage chemotaxis or O2- production. These findings suggest that impairement of the host defence mechanisms due to the reduction in macrophage chemotaxis and O2- production is related to the progression of periodontal disease in plaque-susceptible rats.

  12. Naturally occurring mercury contamination in a pristine environment?

    NASA Astrophysics Data System (ADS)

    Sidle, W. C.

    1993-04-01

    About 19 percent of sampled residential water wells situated in a pristine, granitic Maine (USA) coastal environment have elevated mercury concentrations according to USEPA standards. There are no identified anthropogenic sources for mercury but some local granitoids have anomalous mercury concentrations in the Waldoboro Pluton Complex (WPC). Site-specific hydrogeologic conditions appear to have aggravated what is otherwise only trace amounts of some naturally occurring toxic analytes in the groundwater in contact with the suspect granitoids of the WPC. The extent of mercury in this crystalline rock environment is examined here. It is prudent to exercise preventive measures and appropriately site water supply wells and not expect complete remediation of the affected homeowners' wells.

  13. Vampire bat reproductive control by a naturally occurring phytooestrogen.

    PubMed

    Serrano, Hector; Pérez-Rivero, Juan-José; Aguilar-Setién, Alvaro; de-Paz, Octavio; Villa-Godoy, Alejandro

    2007-01-01

    Rabies transmission by wild animals has not being controlled satisfactorily. One major rabies vector to humans and cattle is the hematophagous vampire bat Desmodus rotundus whose distribution is still increasing in the Americas. Of all of the strategies currently in place to control this vector, none of them are really specific and some have ecological impacts. In the present study we used a naturally occurring phytoestrogen on a small vampire bat colony. After collection, bats were fed bovine blood containing 200 microg coumestrol for a 30-day period. After treatment, gonads were excised and processed for histological evaluation. Data indicate that coumestrol adversely affects gonad histology and has a possible impact on the fertility of both male and female vampire bats.

  14. Temporal variations of natural and anthropogenic radionuclides in sea otter skull tissue in the North Pacific Ocean

    USGS Publications Warehouse

    Baskaran, M.; Hong, G.-H.; Dayton, S.; Bodkin, J.L.; Kelly, J.J.

    2003-01-01

    Marine mammals being in the top predator in the food web tend to accumulate organic and inorganic contaminants from the environment. The body burden of contaminants in these species could reflect their foods and thus contaminant levels could serve as proxies on the changes of ecosystem. A pilot study was carried out to investigate the possibility of radionuclide leakage at Amchitka using a suite of sea otter (Enhydra lutris) skulls collected near Amchitka nuclear test-sites before (1950s) and after the testing (1990s), and at Adak, another Aleutian Island, about 300 km from Amchitka, where the potential impact of radionuclide leakage from Amchitka is expected to be negligible. In addition, the naturally occurring and anthropogenic radionuclide content on the sea otter skull was also utilized to investigate if there was any significant ecosystem changes in the environment. Concentration of 210Pb in sea otter bones collected during the 1950's was significantly higher than those collected in the 1990's. We propose that among the various factors that could cause this higher enrichment in 210Pb, changes in the sea otter prey is the most likely one. Comparison of the 137Cs, 90Sr, 239,240Pu concentrations appear not to be significantly higher in sea otter skulls collected in 1990s from Amchitka where the underground tests in 1965-71 than those from Adak, although significant differences were detected among different groups collected at various times.

  15. Temporal variations of natural and anthropogenic radionuclides in sea otter skull tissue in the North Pacific Ocean

    USGS Publications Warehouse

    Baskaran, M.; Hong, G.-H.; Dayton, S.; Bodkin, J.L.; Kelley, J.J.

    2002-01-01

    Marine mammals being among the top predators in the food web tend to accumulate organic and inorganic contaminants from the environment. The body burden of contaminants in these species could reflect their foods and thus contaminant levels could serve as proxies on the changes of ecosystem. A pilot study was carried out to investigate the possibility of radionuclide leakage at Amchitka using a suite of sea otter (Enhydra lutris) skulls collected near Amchitka nuclear test-sites before (1950s) and after the testing (1990s), and at Adak, another Aleutian Island, about 300 km from Amchitka, where the potential impact of radionuclide leakage from Amchitka is expected to be negligible. In addition, the naturally occurring and anthropogenic radionuclide content on the sea otter skull was also utilized to investigate if there was any significant ecosystem changes in the environment. Concentration of 210Pb in sea otter bones collected during the 1950s was significantly higher than those collected in the 1990s. We propose that among the various factors that could cause this higher enrichment in 210Pb, changes in the sea otter prey is the most likely one. Comparison of the 137Cs, 90Sr, 239,240Pu concentrations appear not to be significantly higher in sea otter skulls collected in 1990s from Amchitka where the underground tests in 1965-71 than those from Adak, although significant differences were detected among different groups collected at various times. ?? 2002 Elsevier Science Ltd. All rights reserved.

  16. Multifaceted ability of naturally occurring polyphenols against metastatic cancer.

    PubMed

    Zhou, Qingyu; Bennett, Lunawati L; Zhou, Shufeng

    2016-04-01

    Although cancer metastases are known to be the main cause of cancer-related deaths, truly effective antimetastatic therapeutics remain scarce in clinical practice. Naturally occurring polyphenols are the most abundant antioxidants in human diets. Many of them possess chemopreventive and chemotherapeutic properties against various types of cancer. Recent advances in understanding the molecular pathways that mediate cancer development and progression have led to an increase of interest in preclinical investigations on the mechanisms underlying anticancer activity of polyphenols. In particular, an increasing number of preclinical studies using cultured cells and animal models have demonstrated the inhibitory effects of polyphenols on tumour cell invasion and metastasis, thereby highlighting the potential of polyphenols against metastatic cancer. This review specifically addresses growing evidence of the capability of polyphenols to impair the invasion and migration of tumour cells through a diverse set of mechanisms, including downregulation of expression of matrix metalloproteinases, modulation of regulators of epithelial-mesenchymal transition, interference with Met signalling, inhibition of nuclear factor-kappa B mediated transcription, and so on. Given that metastasis occurs through a multistep process in which each step is regulated by a complex network of signalling pathways, the multi-function and multi-target characteristics of polyphenols render those promising candidates for effective adjuvant therapy against metastatic cancer.

  17. Naturally occurring allele diversity allows potato cultivation in northern latitudes.

    PubMed

    Kloosterman, Bjorn; Abelenda, José A; Gomez, María del Mar Carretero; Oortwijn, Marian; de Boer, Jan M; Kowitwanich, Krissana; Horvath, Beatrix M; van Eck, Herman J; Smaczniak, Cezary; Prat, Salomé; Visser, Richard G F; Bachem, Christian W B

    2013-03-14

    Potato (Solanum tuberosum L.) originates from the Andes and evolved short-day-dependent tuber formation as a vegetative propagation strategy. Here we describe the identification of a central regulator underlying a major-effect quantitative trait locus for plant maturity and initiation of tuber development. We show that this gene belongs to the family of DOF (DNA-binding with one finger) transcription factors and regulates tuberization and plant life cycle length, by acting as a mediator between the circadian clock and the StSP6A mobile tuberization signal. We also show that natural allelic variants evade post-translational light regulation, allowing cultivation outside the geographical centre of origin of potato. Potato is a member of the Solanaceae family and is one of the world's most important food crops. This annual plant originates from the Andean regions of South America. Potato develops tubers from underground stems called stolons. Its equatorial origin makes potato essentially short-day dependent for tuberization and potato will not make tubers in the long-day conditions of spring and summer in the northern latitudes. When introduced in temperate zones, wild material will form tubers in the course of the autumnal shortening of day-length. Thus, one of the first selected traits in potato leading to a European potato type is likely to have been long-day acclimation for tuberization. Potato breeders can exploit the naturally occurring variation in tuberization onset and life cycle length, allowing varietal breeding for different latitudes, harvest times and markets.

  18. Discovering Psychological Principles by Mining Naturally Occurring Data Sets.

    PubMed

    Goldstone, Robert L; Lupyan, Gary

    2016-07-01

    The very expertise with which psychologists wield their tools for achieving laboratory control may have had the unwelcome effect of blinding psychologists to the possibilities of discovering principles of behavior without conducting experiments. When creatively interrogated, a diverse range of large, real-world data sets provides powerful diagnostic tools for revealing principles of human judgment, perception, categorization, decision-making, language use, inference, problem solving, and representation. Examples of these data sets include patterns of website links, dictionaries, logs of group interactions, collections of images and image tags, text corpora, history of financial transactions, trends in twitter tag usage and propagation, patents, consumer product sales, performance in high-stakes sporting events, dialect maps, and scientific citations. The goal of this issue is to present some exemplary case studies of mining naturally existing data sets to reveal important principles and phenomena in cognitive science, and to discuss some of the underlying issues involved with conducting traditional experiments, analyses of naturally occurring data, computational modeling, and the synthesis of all three methods.

  19. Sequestering Naturally Occurring Liquid Carbon Dioxide in the Deep Ocean

    NASA Astrophysics Data System (ADS)

    Capron, M. E.

    2008-12-01

    Liquid carbon dioxide has been found as shallow as 1,500 meters in seafloor ooze. Did the liquid carbon dioxide originate from volcanic activity? Or did bacteria convert organic matter, which started as atmospheric carbon dioxide, into methane and liquid carbon dioxide? At typical ocean temperatures carbon dioxide coming out of solution below 600 meters will be liquid. Therefore, one likely mechanism for generating liquid carbon dioxide in seafloor ooze is the bacterial decomposition of organic matter. This paper examines quantitative and qualitative bacterial decomposition of aquatic biomass, with an emphasis on assessing and demonstrating feasibility. Calculations suggest natural processes sequestering liquid carbon dioxide in the seafloor can be sustainably increased to decrease atmospheric carbon dioxide concentrations. First, algae growing on the ocean surface absorb carbon dioxide. The algae are then gathered into a submerged container. Naturally occurring bacteria will digest the algae producing methane, liquid carbon dioxide, and ammonium. The ammonium can be recycled as a nutrient for growing more algae. Bacterial decomposition continues in dilute solutions with any biomass. The process does not require any particular biomass. Also, concentrating the biomass by removing water is not essential. The buoyancy provided by water allows relatively inexpensive tension fabric structures to contain the dilute algae and decomposition products. Calculations based on algae growth in open ponds and experience with bacterial decomposition at 1 to 5 bar pressures suggest the economics of the associated macro-algae growing and harvesting can favor increasing ocean species diversity.

  20. Analysis of natural radionuclides in soil samples of Purola area of Garhwal Himalaya, India.

    PubMed

    Yadav, Manjulata; Rawat, Mukesh; Dangwal, Anoop; Prasad, Mukesh; Gusain, G S; Ramola, R C

    2015-11-01

    Naturally occurring radioactive materials are widely spread in the earth's environment, being distributed in soil, rocks, water, air, plants and even within the human body. All of these sources have contributed to an increase in the levels of environmental radioactivity and population radiation doses. This paper presents the activity level due to the presence of (226)Ra, (232)Th and (40)K in soil samples of Purola area in Garhwal Himalaya region. The measured activity of (226)Ra, (232)Th and (40)K in collected soil samples of Purola was found to vary from 13±10 to 55±10 Bq kg(-1) with an average of 31±2 Bq kg(-1), 13±10 to 101±13 Bq kg(-1) with an average 30±3 Bq kg(-1) and 150±81 to 1310±154 Bq kg(-1) with an average 583±30 Bq kg(-1), respectively. The radium equivalent activity in collected soil samples was found to vary from 47 to 221 Bq kg(-1) with an average of 115 Bq kg(-1). The total absorbed gamma dose rate in this area was found to vary from 22 to 93 nGy h(-1) with an average of 55 nGy h(-1). The distribution of these radionuclides in the soil of study area is discussed in details. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Natural and man-made radionuclides in sediments of an inlet in Rio de Janeiro State, Brazil.

    PubMed

    Carvalho, Franciane Martins de; Lauria, Dejanira da Costa; Ribeiro, Fernando Carlos Araújo; Fonseca, Rafael Tonelli; Peres, Sueli da Silva; Martins, Nádia Soido Falcão

    2016-06-15

    The distribution of natural radionuclides (226)Ra, (228)Ra, (40)K and man-made radionuclides ((54)Mn, (60)Co and (137) Cs) in the surface sediments of an inlet of Ribeira Bay were investigated. Sediment samples were collected and analyzed for radionuclides, organic matter, carbonate, sulfate, cationic exchange capacity and grain size composition. The natural radionuclide concentrations ranged from 4.4 to 45, from 10 to 93, from 66 to 1347Bq·kg(-1) dry weight for (226)Ra, (228)Ra and (40)K, respectively. Natural radionuclide concentrations tend to be higher in the silt fraction, which determines their pattern distributions. Only one sample presented measurable concentration for (137)Cs, while (54)Mn was detected in two samples and (60)Co in four sediment samples. Man-made radionuclides present a maximum value of dose external four times lower than the normal background and the potential risk due to the presence of man-made radionuclides in sediments is lower than the risk provided by the natural radionuclides. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Seasonal immunoregulation in a naturally-occurring vertebrate.

    PubMed

    Brown, Martha; Hablützel, Pascal; Friberg, Ida M; Thomason, Anna G; Stewart, Alexander; Pachebat, Justin A; Jackson, Joseph A

    2016-05-18

    Fishes show seasonal patterns of immunity, but such phenomena are imperfectly understood in vertebrates generally, even in humans and mice. As these seasonal patterns may link to infectious disease risk and individual condition, the nature of their control has real practical implications. Here we characterize seasonal dynamics in the expression of conserved vertebrate immunity genes in a naturally-occurring piscine model, the three-spined stickleback. We made genome-wide measurements (RNAseq) of whole-fish mRNA pools (n = 36) at the end of summer and winter in contrasting habitats (riverine and lacustrine) and focussed on common trends to filter habitat-specific from overarching temporal responses. We corroborated this analysis with targeted year-round whole-fish gene expression (Q-PCR) studies in a different year (n = 478). We also considered seasonal tissue-specific expression (6 tissues) (n = 15) at a third contrasting (euryhaline) locality by Q-PCR, further validating the generality of the patterns seen in whole fish analyses. Extremes of season were the dominant predictor of immune expression (compared to sex, ontogeny or habitat). Signatures of adaptive immunity were elevated in late summer. In contrast, late winter was accompanied by signatures of innate immunity (including IL-1 signalling and non-classical complement activity) and modulated toll-like receptor signalling. Negative regulators of T-cell activity were prominent amongst winter-biased genes, suggesting that adaptive immunity is actively down-regulated during winter rather than passively tracking ambient temperature. Network analyses identified a small set of immune genes that might lie close to a regulatory axis. These genes acted as hubs linking summer-biased adaptive pathways, winter-biased innate pathways and other organismal processes, including growth, metabolic dynamics and responses to stress and temperature. Seasonal change was most pronounced in the gill, which contains a

  3. Forecasting Seizures in Dogs with Naturally Occurring Epilepsy

    PubMed Central

    Stead, S. Matt; Brinkmann, Ben; Vasoli, Vincent; Crepeau, Daniel; Vite, Charles H.; Sturges, Beverly; Ruedebusch, Vanessa; Mavoori, Jaideep; Leyde, Kent; Sheffield, W. Douglas; Litt, Brian; Worrell, Gregory A.

    2014-01-01

    Seizure forecasting has the potential to create new therapeutic strategies for epilepsy, such as providing patient warnings and delivering preemptive therapy. Progress on seizure forecasting, however, has been hindered by lack of sufficient data to rigorously evaluate the hypothesis that seizures are preceded by physiological changes, and are not simply random events. We investigated seizure forecasting in three dogs with naturally occurring focal epilepsy implanted with a device recording continuous intracranial EEG (iEEG). The iEEG spectral power in six frequency bands: delta (0.1–4 Hz), theta (4–8 Hz), alpha (8–12 Hz), beta (12–30 Hz), low-gamma (30–70 Hz), and high-gamma (70–180 Hz), were used as features. Logistic regression classifiers were trained to discriminate labeled pre-ictal and inter-ictal data segments using combinations of the band spectral power features. Performance was assessed on separate test data sets via 10-fold cross-validation. A total of 125 spontaneous seizures were detected in continuous iEEG recordings spanning 6.5 to 15 months from 3 dogs. When considering all seizures, the seizure forecasting algorithm performed significantly better than a Poisson-model chance predictor constrained to have the same time in warning for all 3 dogs over a range of total warning times. Seizure clusters were observed in all 3 dogs, and when the effect of seizure clusters was decreased by considering the subset of seizures separated by at least 4 hours, the forecasting performance remained better than chance for a subset of algorithm parameters. These results demonstrate that seizures in canine epilepsy are not randomly occurring events, and highlight the feasibility of long-term seizure forecasting using iEEG monitoring. PMID:24416133

  4. Forecasting seizures in dogs with naturally occurring epilepsy.

    PubMed

    Howbert, J Jeffry; Patterson, Edward E; Stead, S Matt; Brinkmann, Ben; Vasoli, Vincent; Crepeau, Daniel; Vite, Charles H; Sturges, Beverly; Ruedebusch, Vanessa; Mavoori, Jaideep; Leyde, Kent; Sheffield, W Douglas; Litt, Brian; Worrell, Gregory A

    2014-01-01

    Seizure forecasting has the potential to create new therapeutic strategies for epilepsy, such as providing patient warnings and delivering preemptive therapy. Progress on seizure forecasting, however, has been hindered by lack of sufficient data to rigorously evaluate the hypothesis that seizures are preceded by physiological changes, and are not simply random events. We investigated seizure forecasting in three dogs with naturally occurring focal epilepsy implanted with a device recording continuous intracranial EEG (iEEG). The iEEG spectral power in six frequency bands: delta (0.1-4 Hz), theta (4-8 Hz), alpha (8-12 Hz), beta (12-30 Hz), low-gamma (30-70 Hz), and high-gamma (70-180 Hz), were used as features. Logistic regression classifiers were trained to discriminate labeled pre-ictal and inter-ictal data segments using combinations of the band spectral power features. Performance was assessed on separate test data sets via 10-fold cross-validation. A total of 125 spontaneous seizures were detected in continuous iEEG recordings spanning 6.5 to 15 months from 3 dogs. When considering all seizures, the seizure forecasting algorithm performed significantly better than a Poisson-model chance predictor constrained to have the same time in warning for all 3 dogs over a range of total warning times. Seizure clusters were observed in all 3 dogs, and when the effect of seizure clusters was decreased by considering the subset of seizures separated by at least 4 hours, the forecasting performance remained better than chance for a subset of algorithm parameters. These results demonstrate that seizures in canine epilepsy are not randomly occurring events, and highlight the feasibility of long-term seizure forecasting using iEEG monitoring.

  5. Seasonality in the flux of natural radionuclides and plutonium in the deep Sargasso Sea. Technical report

    SciTech Connect

    Bacon, M.P.; Fleer, A.P.; Deuser, W.G.

    1985-01-01

    A record of radionuclide fluxes at a deep-ocean station near Bermuda (32/sup 0/ 05 min N, 64/sup 0/ 15 min W) was obtained from analysis of a 3-year collection of sediment-trap samples. The trap was placed at a depth of 3200 m, 1000 m above the sea floor, and the samples were recovered at 2-month intervals. Concentrations of U-238, -234, Th-232, -230, -228, Pa-231, Pb-210, Po-210, and Pu-239 and -240 were measured in the trapped material. Most of the radionuclide activity was found in the <37-micron sieved fraction. All radionuclide fluxes showed seasonal variations in phase with the variations in total sediment flux, which had been previously shown to be closely tied to the annual cycle of primary production in the overlying surface water. Seasonal variations are especially noteworthy for Th-230 and Pa-231, considering that most of their production occurs in the water column below the euphotic zone. Evidently the seasonal influence is transmitted downward by the varying particle flux so that radionuclide scavenging rates at depth, as well as at the surface, are affected. It is suggested that this could be brought about by seasonal variations in the flux of marine snow or in the rate of fecal-matter production in the deep-water column. Keywords: Pelagic sedimentation.

  6. Natural radionuclides in the South Indian foods and their annual dose

    NASA Astrophysics Data System (ADS)

    Shanthi, G.; Thampi Thanka Kumaran, J.; Gnana Raj, G. Allan; Maniyan, C. G.

    2010-07-01

    The study was carried out to evaluate the radioactivity concentration in the food crops grown in high-level natural radioactive area (HLNRA) in south west India. Food samples collected were analysed by means of a gamma spectroscopy and estimated annual dietary intakes of the radioisotopes 226Ra, 228Ra, 228Th and 40K. The annual intake of the food stuffs was estimated on the basis of their average annual consumption. Calculations were also made to determine the effective dose to an individual consuming such diets. The intakes of these radionuclides were calculated using the concentrations in south Indian foods and daily consumption rates of these foods. Daily intakes of these radionuclides were as follows: 226Ra, 0.001-1.87; 228Ra, 0.0023-1.26, 228Th, 0.01-14.09 40K, 0.46-49.39 Bq/day. The daily internal dose resulting from ingestion of radionuclides in food was 4.92 μSv/day and the annual dose was 1.79 mSv/yr. The radionuclides with highest consumption is 40K.

  7. Franckeite as a naturally occurring van der Waals heterostructure

    PubMed Central

    Molina-Mendoza, Aday J.; Giovanelli, Emerson; Paz, Wendel S.; Niño, Miguel Angel; Island, Joshua O.; Evangeli, Charalambos; Aballe, Lucía; Foerster, Michael; van der Zant, Herre S. J.; Rubio-Bollinger, Gabino; Agraït, Nicolás; Palacios, J. J.; Pérez, Emilio M.; Castellanos-Gomez, Andres

    2017-01-01

    The fabrication of van der Waals heterostructures, artificial materials assembled by individual stacking of 2D layers, is among the most promising directions in 2D materials research. Until now, the most widespread approach to stack 2D layers relies on deterministic placement methods, which are cumbersome and tend to suffer from poor control over the lattice orientations and the presence of unwanted interlayer adsorbates. Here, we present a different approach to fabricate ultrathin heterostructures by exfoliation of bulk franckeite which is a naturally occurring and air stable van der Waals heterostructure (composed of alternating SnS2-like and PbS-like layers stacked on top of each other). Presenting both an attractive narrow bandgap (<0.7 eV) and p-type doping, we find that the material can be exfoliated both mechanically and chemically down to few-layer thicknesses. We present extensive theoretical and experimental characterizations of the material's electronic properties and crystal structure, and explore applications for near-infrared photodetectors. PMID:28194037

  8. Franckeite as a naturally occurring van der Waals heterostructure.

    PubMed

    Molina-Mendoza, Aday J; Giovanelli, Emerson; Paz, Wendel S; Niño, Miguel Angel; Island, Joshua O; Evangeli, Charalambos; Aballe, Lucía; Foerster, Michael; van der Zant, Herre S J; Rubio-Bollinger, Gabino; Agraït, Nicolás; Palacios, J J; Pérez, Emilio M; Castellanos-Gomez, Andres

    2017-02-13

    The fabrication of van der Waals heterostructures, artificial materials assembled by individual stacking of 2D layers, is among the most promising directions in 2D materials research. Until now, the most widespread approach to stack 2D layers relies on deterministic placement methods, which are cumbersome and tend to suffer from poor control over the lattice orientations and the presence of unwanted interlayer adsorbates. Here, we present a different approach to fabricate ultrathin heterostructures by exfoliation of bulk franckeite which is a naturally occurring and air stable van der Waals heterostructure (composed of alternating SnS2-like and PbS-like layers stacked on top of each other). Presenting both an attractive narrow bandgap (<0.7 eV) and p-type doping, we find that the material can be exfoliated both mechanically and chemically down to few-layer thicknesses. We present extensive theoretical and experimental characterizations of the material's electronic properties and crystal structure, and explore applications for near-infrared photodetectors.

  9. Alendronate treatment of naturally-occurring periodontitis in beagle dogs.

    PubMed

    Reddy, M S; Weatherford, T W; Smith, C A; West, B D; Jeffcoat, M K; Jacks, T M

    1995-03-01

    The treatment of periodontal disease has been largely directed at the microbiological etiology. The prevention of bone loss by modulating the host response to the bacteria may be a useful adjunctive method in the management of periodontitis. Alendronate, an amino bisphosphonate, may inhibit bone loss in osteolytic diseases by altering osteoclast activity. The objective of this double-blind study was to evaluate alendronate inhibition of alveolar bone loss in the naturally occurring beagle dog model of periodontitis. Sixteen 7 to 9 year old beagles with moderate-to-severe periodontitis were studied for 6 months. The dogs were stratified into two groups based on initial periodontal severity. One group received 3.0 mg/kg alendronate weekly orally and the other group received a placebo. Silk ligatures were placed on the study teeth for the first 3 months of the study to exacerbate the periodontal destruction. Clinical data were collected for attachment level, gingival index, plaque index, and mobility at baseline and one-month intervals. Intraoral radiographs were made at baseline and at 3 and 6 months. The mandibles were processed for histology at month 6. The radiographs were analyzed by digital image analysis of the subtracted images. A statistically significant difference in bone mass (P < 0.001) was observed between the alendronate and placebo groups. The bisphosphonate had no effect on the clinical parameters of gingival inflammation or plaque. A trend toward decreased attachment loss and mobility was observed in favor of the alendronate group.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. Naturally occurring regulatory T cells: markers, mechanisms, and manipulation.

    PubMed

    Schmetterer, Klaus G; Neunkirchner, Alina; Pickl, Winfried F

    2012-06-01

    Naturally occurring CD4(+)CD25(high) forkhead box protein 3 (FOXP3)(+) regulatory T cells (nTregs) are key mediators of immunity, which orchestrate and maintain tolerance to self and foreign antigens. In the recent 1.5 decades, a multitude of studies have aimed to define the phenotype and function of nTregs and to assess their therapeutic potential for modulating immune mediated disorders such as autoimmunity, allergy, and episodes of transplant rejection. In this review, we summarize the current knowledge on the biology of nTregs. We address the exact definition of nTregs by specific markers and combinations thereof, which is a prerequisite for the state-of-the-art isolation of defined nTreg populations. Furthermore, we discuss the mechanism by which nTregs mediate immunosuppression and how this knowledge might translate into novel therapeutic modalities. With first clinical studies of nTreg-based therapies being finished, questions concerning the reliable sources of nTregs are becoming more and more eminent. Consequently, approaches allowing conversion of CD4(+) T cells into nTregs by coculture with antigen-presenting cells, cytokines, and/or pharmacological agents are discussed. In addition, genetic engineering approaches for the generation of antigen-specific nTregs are described.

  11. Global distribution of naturally occurring marine hypoxia on continental margins

    NASA Astrophysics Data System (ADS)

    Helly, John J.; Levin, Lisa A.

    2004-09-01

    Hypoxia in the ocean influences biogeochemical cycling of elements, the distribution of marine species and the economic well being of many coastal countries. Previous delineations of hypoxic environments focus on those in enclosed seas where hypoxia may be exacerbated by anthropogenically induced eutrophication. Permanently hypoxic water masses in the open ocean, referred to as oxygen minimum zones, impinge on a much larger seafloor surface area along continental margins of the eastern Pacific, Indian and western Atlantic Oceans. We provide the first global quantification of naturally hypoxic continental margin floor by determining upper and lower oxygen minimum zone depth boundaries from hydrographic data and computing the area between the isobaths using seafloor topography. This approach reveals that there are over one million km 2 of permanently hypoxic shelf and bathyal sea floor, where dissolved oxygen is <0.5 ml l -1; over half (59%) occurs in the northern Indian Ocean. We also document strong variation in the intensity, vertical position and thickness of the OMZ as a function of latitude in the eastern Pacific Ocean and as a function of longitude in the northern Indian Ocean. Seafloor OMZs are regions of low biodiversity and are inhospitable to most commercially valuable marine resources, but support a fascinating array of protozoan and metazoan adaptations to hypoxic conditions.

  12. Conformational Flexibility Differentiates Naturally Occurring Bet v 1 Isoforms.

    PubMed

    Grutsch, Sarina; Fuchs, Julian E; Ahammer, Linda; Kamenik, Anna S; Liedl, Klaus R; Tollinger, Martin

    2017-06-03

    The protein Bet v 1 represents the main cause for allergic reactions to birch pollen in Europe and North America. Structurally homologous isoforms of Bet v 1 can have different properties regarding allergic sensitization and Th2 polarization, most likely due to differential susceptibility to proteolytic cleavage. Using NMR relaxation experiments and molecular dynamics simulations, we demonstrate that the initial proteolytic cleavage sites in two naturally occurring Bet v 1 isoforms, Bet v 1.0101 (Bet v 1a) and Bet v 1.0102 (Bet v 1d), are conformationally flexible. Inaccessible cleavage sites in helices and strands are highly flexible on the microsecond-millisecond time scale, whereas those located in loops display faster nanosecond-microsecond flexibility. The data consistently show that Bet v 1.0102 is more flexible and conformationally heterogeneous than Bet v 1.0101. Moreover, NMR hydrogen-deuterium exchange measurements reveal that the backbone amides in Bet v 1.0102 are significantly more solvent exposed, in agreement with this isoform's higher susceptibility to proteolytic cleavage. The differential conformational flexibility of Bet v 1 isoforms, along with the transient exposure of inaccessible sites to the protein surface, may be linked to proteolytic susceptibility, representing a potential structure-based rationale for the observed differences in Th2 polarization and allergic sensitization.

  13. Conformational Flexibility Differentiates Naturally Occurring Bet v 1 Isoforms

    PubMed Central

    Grutsch, Sarina; Fuchs, Julian E.; Ahammer, Linda; Kamenik, Anna S.; Liedl, Klaus R.; Tollinger, Martin

    2017-01-01

    The protein Bet v 1 represents the main cause for allergic reactions to birch pollen in Europe and North America. Structurally homologous isoforms of Bet v 1 can have different properties regarding allergic sensitization and Th2 polarization, most likely due to differential susceptibility to proteolytic cleavage. Using NMR relaxation experiments and molecular dynamics simulations, we demonstrate that the initial proteolytic cleavage sites in two naturally occurring Bet v 1 isoforms, Bet v 1.0101 (Bet v 1a) and Bet v 1.0102 (Bet v 1d), are conformationally flexible. Inaccessible cleavage sites in helices and strands are highly flexible on the microsecond-millisecond time scale, whereas those located in loops display faster nanosecond-microsecond flexibility. The data consistently show that Bet v 1.0102 is more flexible and conformationally heterogeneous than Bet v 1.0101. Moreover, NMR hydrogen-deuterium exchange measurements reveal that the backbone amides in Bet v 1.0102 are significantly more solvent exposed, in agreement with this isoform’s higher susceptibility to proteolytic cleavage. The differential conformational flexibility of Bet v 1 isoforms, along with the transient exposure of inaccessible sites to the protein surface, may be linked to proteolytic susceptibility, representing a potential structure-based rationale for the observed differences in Th2 polarization and allergic sensitization. PMID:28587205

  14. Pulsed light inactivation of naturally occurring moulds on wheat grain.

    PubMed

    Aron Maftei, Nicoleta; Ramos-Villarroel, Ana Y; Nicolau, Anca I; Martín-Belloso, Olga; Soliva-Fortuny, Robert

    2014-03-15

    Pulsed light (PL) is emerging as a non-thermal technology with excellent prospects for the decontamination of foods and food contact surfaces. Its application for mould inactivation on cereal grains would allow a reduction of storage losses as well as the prevention of mycotoxin contamination at a post-harvest level. The potential of PL for the decontamination of naturally occurring moulds on wheat grain was investigated in this study. Treatments of up to 40 flashes of a fluence of 0.4 J cm⁻² per pulse were applied to both sides of the grain, with an overall energy release ranging from 6.4 to 51.2 J g⁻¹. The most powerful treatment applied to wheat in this study (51.2 J g⁻¹) resulted in a mould reduction of approximately 4 log cycles on samples displaying an initial mould contamination level of 2.2 × 10⁵ CFU g⁻¹. At the same time, the seed germination percentage was only slightly affected. For PL treatments causing an inactivation of 3-4 log cycles, only 14-15% of the germination power of the wheat seeds was lost. The PL treatments attained greater microbial reductions for higher treatment times and lower initial mould loads. The absence of the UV portion of the radiation spectrum was found to significantly reduce the treatment effectiveness. © 2013 Society of Chemical Industry.

  15. Naturally occurring and forced azimuthal modes in a turbulent jet

    NASA Technical Reports Server (NTRS)

    Raman, Ganesh; Rice, Edward J.; Reshotko, Eli

    1991-01-01

    Naturally occurring instability modes in an axisymmetric jet were studied using the modal frequency technique. The evolution of the modal spectrum was obtained for a jet with a Reynolds number based on a diameter of 400,000 for both laminar and turbulent nozzle boundary layers. In the early evolution of the jet the axisymmetric mode was predominant, with the azimuthal modes growing rapidly but dominating only the end of the potential core. The growth of the azimuthal was observed closer to the nozzle exit for the jet in the laminar boundary layer case than for the turbulent. Target modes for efficient excitation of the jet were determined and two cases of excitation were studied. First, a jet was excited simultaneously by two helical modes, m equals plus 1 and m equals minus 1 at a Strouhal number based on jet diameter of 0.15 and the axisymmetric mode, m equals 0 at a jet diameter of 0.6. Second, m equals plus one and m equals minus 1 at jet diameter equals 0.3 and m equals 0 at jet diameter equals 0.6 were excited simultaneously. The downstream evolution of the hydrodynamic modes and the spreading rate of the jet were documented for each case. Higher jet spreading rates, accompanied by distorted jet cross sections were observed for the cases where combinations of axisymmetric and helical forcings were applied.

  16. Franckeite as a naturally occurring van der Waals heterostructure

    NASA Astrophysics Data System (ADS)

    Molina-Mendoza, Aday J.; Giovanelli, Emerson; Paz, Wendel S.; Niño, Miguel Angel; Island, Joshua O.; Evangeli, Charalambos; Aballe, Lucía; Foerster, Michael; van der Zant, Herre S. J.; Rubio-Bollinger, Gabino; Agraït, Nicolás; Palacios, J. J.; Pérez, Emilio M.; Castellanos-Gomez, Andres

    2017-02-01

    The fabrication of van der Waals heterostructures, artificial materials assembled by individual stacking of 2D layers, is among the most promising directions in 2D materials research. Until now, the most widespread approach to stack 2D layers relies on deterministic placement methods, which are cumbersome and tend to suffer from poor control over the lattice orientations and the presence of unwanted interlayer adsorbates. Here, we present a different approach to fabricate ultrathin heterostructures by exfoliation of bulk franckeite which is a naturally occurring and air stable van der Waals heterostructure (composed of alternating SnS2-like and PbS-like layers stacked on top of each other). Presenting both an attractive narrow bandgap (<0.7 eV) and p-type doping, we find that the material can be exfoliated both mechanically and chemically down to few-layer thicknesses. We present extensive theoretical and experimental characterizations of the material's electronic properties and crystal structure, and explore applications for near-infrared photodetectors.

  17. Distribution of natural and anthropogenic radionuclides in heavy rainfall areas in Jordan.

    PubMed

    Ababneh, Anas M; Almomani, Ali M; Alyassin, Abdalmajeid M; Ababneh, Zaid Q

    2012-06-01

    Soil is the main reservoir of both natural and artificial radionuclides, which are transported to the human body through the food chain. Thus, assessment of the level of radioactivity in soil is of crucial importance. Artificial radionuclide concentrations in soil depend heavily on rainfall and weather conditions. In this study, the soil of the Ras Muneef area, which has the highest rainfall in Jordan, was investigated for its natural and anthropogenic radioactive content. The area was divided into four sectors and in each sector three locations were investigated depending on the land use: undisturbed, cultivated or residential. The depth profile of (137)Cs was investigated and found to depend on the land use. In the undisturbed soils, two types of depth profiles were identified: Gaussian and exponentially decreasing. The annual effective dose was found to range from 19.4 to 72.6 μSv, which falls within the worldwide ranges.

  18. Natural radionuclides in cigarette tobacco from Serbian market and effective dose estimate from smoke inhalation.

    PubMed

    Janković Mandić, Ljiljana; Đolić, Maja; Marković, Dragana; Todorović, Dragana; Onjia, Antonije; Dragović, Snežana

    2016-01-01

    The activity concentrations of natural radionuclides ((40)K, (210)Pb, (210)Po, (226)Ra and (228)Ra) in 17 most frequently used cigarette brands in Serbia and corresponding effective doses due to smoke inhalation are presented. The mean annual effective doses for (210)Pb and (210)Po were estimated to be 47.3 and 724 µSv y(-1) for (210)Pb and (210)Po, respectively. Serbia currently has the highest smoking rate in the world. The results of this study indicate the high contribution of the annual effective dose due to smoke inhalation to the total inhalation dose from natural radionuclides. The more effective implementation of actions for reducing smoking prevalence in Serbia is highly needed. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Weathering products of basic rocks as sorptive materials of natural radionuclides

    SciTech Connect

    Omelianenko, B.I.; Niconov, B.S.; Ryzhov, B.I.; Shikina, N.D.

    1994-06-01

    The principal requirements for employing natural minerals as buffer and backfill material in high-level waste (HLW) repositories are high sorptive properties, low water permeability, relatively high thermal conductivity, and thermostability. The major task of the buffer is to prevent the penetration of radionuclides into groundwater. The authors of this report examined weathered basic rocks from three regions of Russia in consideration as a suitable radioactive waste barrier.

  20. Aquifer mineralogy and natural radionuclides in groundwater-the lower Paleozoic of central Texas

    SciTech Connect

    Kim, Y.; Tieh, T.T.; Ledger, E.B.

    1995-10-01

    Water-mineral interactions in an aquifer may give rise to high levels of Ra and Rn in groundwater. An understanding of aquifer mineralogy is therefore essential to determine the sources of natural radionuclides and design possible means for improving water quality. Anomalous Ra and Rn concentrations have been detected in groundwater produced from the Cambrian Hickory and Cap Mountain aquifers in the Llano Uplift area of central Texas. This study examines cored aquifer rock samples, focusing on the abundance, distribution, and nature of occurrence of minerals containing U and Th, parent nuclides of Ra Rn. The Hickory, 136 m thick, consists of a coarse grained lower, a calcareous middle, and a fossiliferous and hematitic upper unit, with thin shale laminae thoughout. The Cap Mountain, 44 m thick, is a sandy limestone. Detrital materials are composed of 77% quartz, 19% feldspars, and 4% lithic fragments. Accessory minerals average less than 1%. Authigenic minerals, primarily carbonate, clay, and Fe-oxide minerals, make up 18% of the bulk rock. Porosity is of secondary origin. Analysis of U in 123 samples by delayed neutron counting shows an average concentration of 3.6 ppm. Shaly samples generally contain significantly higher U. Gamma ray spectrometric analysis of Th in 20 samples yields an average of 13.9 ppm. Fission-track imaging shows that U occurs predominantly in: (1) phosphatic fossil fragments and intraclasts, especially in the Cap Mountain; (2) thin shaly laminae which are more abundant in the Hickory; (3) authigenic minerals including hematite and clay minerals, also common in the Hickory; and (4) detrital accessory minerals. Mobilization of U and its decay products by groundwater can account for the Ra and Rn in the produced water, particularly from intervals where there are high concentrations of shaly laminae, phosphatic materials, or hematitic cement.

  1. Humic substances in natural waters and their complexation with trace metals and radionuclides: a review. [129 references

    SciTech Connect

    Boggs, S. Jr.; Livermore, D.; Seitz, M.G.

    1985-07-01

    Dissolved humic substances (humic and fulvic acids) occur in surface waters and groundwaters in concentrations ranging from less than 1 mg(C)/L to more than 100 mg(C)/L. Humic substances are strong complexing agents for many trace metals in the environment and are also capable of forming stable soluble complexes or chelates with radionuclides. Concentrations of humic materials as low as 1 mg(C)/L can produce a detectable increase in the mobility of some actinide elements by forming soluble complexes that inhibit sorption of the radionuclides onto rock materials. The stability of trace metal- or radionuclide-organic complexes is commonly measured by an empirically determined conditional stability constant (K'), which is based on the ratio of complexed metal (radionuclide) in solution to the product concentration of uncomplexed metal and humic complexant. Larger values of stability constants indicate greater complex stability. The stability of radionuclide-organic complexes is affected both by concentration variables and envionmental factors. In general, complexing is favored by increased of radionuclide, increased pH, and decreased ionic strength. Actinide elements are generally most soluble in their higher oxidation states. Radionuclides can also form stable, insoluble complexes with humic materials that tend to reduce radionuclide mobility. These insoluble complexes may be radionuclide-humate colloids that subsequently precipitate from solution, or complexes of radionuclides and humic substances that sorb to clay minerals or other soil particulates strongly enough to immobilize the radionuclides. Colloid formation appears to be favored by increased radionuclide concentration and lowered pH; however, the conditions that favor formation of insoluble complexes that sorb to particulates are still poorly understood. 129 refs., 25 figs., 19 tabs.

  2. Identification of Telomerase-activating Blends From Naturally Occurring Compounds.

    PubMed

    Ait-Ghezala, Ghania; Hassan, Samira; Tweed, Miles; Paris, Daniel; Crynen, Gogce; Zakirova, Zuchra; Crynen, Stefan; Crawford, Fiona

    2016-06-01

    telomerase activity, and combinations of the top-ranking compounds were able to increase telomerase activity significantly, from 51% to 290%, relative to controls. Conclusions • The results have confirmed that many naturally occurring compounds hold the potential to activate telomerase and that certain of those compounds have demonstrated synergistic effects to produce more potent blends. Given the relationship between telomere shortening, aging, and the decline of tissue function, it is reasonable to hypothesize that such telomerase-activating blends may have health-promoting benefits, particularly in relation to aging-associated conditions. Further investigation of such blends in human studies that are designed to evaluate safety and the effects on telomere length are thus warranted.

  3. Antituberculosis Activity of a Naturally Occurring Flavonoid, Isorhamnetin.

    PubMed

    Jnawali, Hum Nath; Jeon, Dasom; Jeong, Min-Cheol; Lee, Eunjung; Jin, Bongwhan; Ryoo, Sungweon; Yoo, Jungheon; Jung, In Duk; Lee, Seung Jun; Park, Yeong-Min; Kim, Yangmee

    2016-04-22

    Isorhamnetin (1) is a naturally occurring flavonoid having anticancer and anti-inflammatory properties. The present study demonstrated that 1 had antimycobacterial effects on Mycobacterium tuberculosis H37Rv, multi-drug- and extensively drug-resistant clinical isolates with minimum inhibitory concentrations of 158 and 316 μM, respectively. Mycobacteria mainly affect the lungs, causing an intense local inflammatory response that is critical to the pathogenesis of tuberculosis. We investigated the effects of 1 on interferon (IFN)-γ-stimulated human lung fibroblast MRC-5 cells. Isorhamnetin suppressed the release of tumor necrosis factor (TNF)-α and interleukin (IL)-12. A nontoxic dose of 1 reduced mRNA expression of TNF-α, IL-1β, IL-6, IL-12, and matrix metalloproteinase-1 in IFN-γ-stimulated cells. Isorhamnetin inhibited IFN-γ-mediated stimulation of extracellular signal-regulated kinase and p38 mitogen-activated protein kinase and showed high-affinity binding to these kinases (binding constants: 4.46 × 10(6) M(-1) and 7.6 × 10(6) M(-1), respectively). The 4'-hydroxy group and the 3'-methoxy group of the B-ring and the 5-hydroxy group of the A-ring of 1 play key roles in these binding interactions. A mouse in vivo study of lipopolysaccharide-induced lung inflammation revealed that a nontoxic dose of 1 reduced the levels of IL-1β, IL-6, IL-12, and INF-γ in lung tissue. These data provide the first evidence that 1 could be developed as a potent antituberculosis drug.

  4. Prevalence of naturally occurring cartilage defects in the ovine knee.

    PubMed

    Vandeweerd, J-M; Hontoir, F; Kirschvink, N; Clegg, P; Nisolle, J-F; Antoine, N; Gustin, P

    2013-08-01

    To determine the prevalence, anatomical location and severity of cartilage defects in the stifle (knee) within a population of adult ewes (N = 65). Articular cartilage (AC) of the distal femur, proximal tibia and patella was assessed using Osteoarthritis Research Society International (OARSI) recommendations for macroscopic and microscopic scoring of ovine cartilage. Synovial fluid analysis and histology of the synovial membrane were performed. All limbs were examined by computed tomography. Twenty-eight sheep (n = 28; 43%) presented at least one score 2 or score 3 lesion. Twenty-two (n = 22; 34%) sheep were macroscopically normal. Most frequent localizations of lesions were: axial aspect of the central third of the medial tibial condyle (32.7% of the lesions), middle third of the medial femoral condyle (29.4%), middle third of the articular surface of the patella (9.8%), and axial aspect of the central third of the lateral tibial condyle (9.8%). Grade of macroscopic lesions was significantly (H (3) = 29.31, P 0.000) affected by age. Macroscopic score correlated well with histological changes that can be found in osteoarthritis (OA) (r 0.83; P 0.000). Neither clinical signs of OA, nor cytological and histological signs of inflammation were identified, while imaging abnormalities were very rare. Our data seem to indicate that naturally occurring OA exists in ageing sheep, at least subclinically. It might be useful to take into account prevalent cartilage defects at baseline in studies using ovine models. Copyright © 2013 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  5. Probabilities of Natural Events Occurring at Savannah River Plant

    SciTech Connect

    Huang, J.C.

    2001-07-17

    This report documents the comprehensive evaluation of probability models of natural events which are applicable to Savannah River Plant. The probability curves selected for these natural events are recommended to be used by all SRP/SRL safety analysts. This will ensure a consistency in analysis methodology for postulated SAR incidents involving natural phenomena.

  6. Naturally occurring asbestos: a recurring public policy challenge.

    PubMed

    Lee, R J; Strohmeier, B R; Bunker, K L; Van Orden, D R

    2008-05-01

    The potential environmental hazards and associated public health issues related to exposure to respirable dusts from the vicinity of natural in-place asbestos deposits (commonly referred to as naturally occurring asbestos, NOA) have gained the regulatory and media spotlight in many areas around the United States, such as Libby, MT, Fairfax County, VA, and El Dorado Hills, CA, among others. NOA deposits may be present in a variety of geologic formations. It has been suggested that airborne asbestos may be released from NOA deposits, and absent appropriate engineering controls, may pose a potential health hazard if these rocks are crushed or exposed to natural weathering and erosion or to human activities that create dust. The issue that needs to be addressed at a policy level is the method of assessing exposures to elongated rock fragments ubiquitous in dust clouds in these same environments and the associated risk. Elongated rock fragments and single crystal minerals present in NOA have been construed by some as having attributes, including the health effects, of asbestos fibers. However, the Occupational Safety and Health Administration (OSHA), Mine Safety and Health Administration (MSHA), and the Consumer Products Safety Commission (CPSC) found that the scientific evidence did not support this assumption. As in many environmental fields of study, the evidence is often disputed. Regulatory policy is not uniform on the subject of rock fragments, even within single agencies. The core of the issue is whether the risk parameters associated with exposures to commercial asbestos can or should be applied to rock fragments meeting an arbitrary set of particle dimensions used for counting asbestos fibers. Inappropriate inclusion of particles or fragments results in dilution of risk and needless expenditure of resources. On the other hand, inappropriate exclusion of particles or fragments may result in increased and unnecessary risk. Some of the fastest growing counties in

  7. Naturally occurring radioactive materials (NORMs) generated from lignite-fired power plants in Kosovo.

    PubMed

    Hasani, F; Shala, F; Xhixha, G; Xhixha, M K; Hodolli, G; Kadiri, S; Bylyku, E; Cfarku, F

    2014-12-01

    The energy production in Kosovo depends primarily on lignite-fired power plants. During coal combustion, huge amounts of fly ash and bottom ash are generated, which may result in enriched natural radionuclides; therefore, these radionuclides need to be investigated to identify the possible processes that may lead to the radiological exposure of workers and the local population. Lignite samples and NORMs of fly ash and bottom ash generated in lignite-fired power plants in Kosovo are analyzed using a gamma-ray spectrometry method for the activity concentration of natural radionuclides. The average activity concentrations of (40)K, (226)Ra and (232)Th in lignite are found to be 36 ± 8 Bq kg(-1), 9 ± 1 Bq kg(-1) and 9 ± 3 Bq kg(-1), respectively. Indications on the occurrence and geochemical behavior of uranium in the lignite matrix are suggested. The activity concentrations of natural radionuclides in fly ash and bottom ash samples are found to be concentrated from 3 to 5 times that of the feeding lignite. The external gamma-ray absorbed dose rate and the activity concentration index are calculated to assess the radiological hazard arising from ash disposal and recycling in the cement industry.

  8. Natural radionuclides in waste water discharged from coal-fired power plants in Serbia.

    PubMed

    Janković, Marija M; Todorović, Dragana J; Sarap, Nataša B; Krneta Nikolić, Jelena D; Rajačić, Milica M; Pantelić, Gordana K

    2016-12-01

    Investigation of the natural radioactivity levels in water around power plants, as well as in plants, coal, ash, slag and soil, and to assess the associated radiation hazard is becoming an emerging and interesting topic. This paper is focused on the results of the radioactivity analysis in waste water samples from five coal-fired power plants in Serbia (Nikola Tesla A, Nikola Tesla B, Kolubara, Morava and Kostolac), which were analyzed in the period 2003-2015. River water samples taken upstream and downstream from the power plants, drain water and overflow water were analyzed. In the water samples gamma spectrometry analysis was performed as well as determination of gross alpha and beta activity. Natural radionuclide (40)K was detected by gamma spectrometry, while the concentrations of other radionuclides, (226)Ra, (235)U and (238)U, usually were below the minimum detection activity (MDA). (232)Th and artificial radionuclide (137)Cs were not detected in these samples. Gross alpha and beta activities were determined by the α/β low level proportional counter Thermo Eberline FHT 770 T. In the analyzed samples, gross alpha activity ranged from MDA to 0.47 Bq L(-)(1), while the gross beta activity ranged from MDA to 1.55 Bq L(-)(1).

  9. Soil and sediment sample analysis for the sequential determination of natural and anthropogenic radionuclides.

    PubMed

    Michel, H; Levent, D; Barci, V; Barci-Funel, G; Hurel, C

    2008-02-15

    A new sequential method for the determination of both natural (U, Th) and anthropogenic (Sr, Cs, Pu, Am) radionuclides has been developed for application to soil and sediment samples. The procedure was optimised using a reference sediment (IAEA-368) and reference soils (IAEA-375 and IAEA-326). Reference materials were first digested using acids (leaching), 'total' acids on hot plate, and acids in microwave in order to compare the different digestion technique. Then, the separation and purification were made by anion exchange resin and selective extraction chromatography: transuranic (TRU) and strontium (SR) resins. Natural and anthropogenic alpha radionuclides were separated by uranium and tetravalent actinide (UTEVA) resin, considering different acid elution medium. Finally, alpha and gamma semiconductor spectrometer and liquid scintillation spectrometer were used to measure radionuclide activities. The results obtained for strontium-90, cesium-137, thorium-232, uranium-238, plutonium-239+240 and americium-241 isotopes by the proposed method for the reference materials provided excellent agreement with the recommended values and good chemical recoveries. Plutonium isotopes in alpha spectrometry planchet deposits could be also analysed by ICPMS.

  10. Manufactured Home Testing in Simulated and Naturally Occurring High Winds

    SciTech Connect

    W. D. Richins; T. K. Larson

    2006-08-01

    A typical double-wide manufactured home was tested in simulated and naturally occurring high winds to understand structural behavior and improve performance during severe windstorms. Seven (7) lateral load tests were conducted on a double-wide manufactured home at a remote field test site in Wyoming. An extensive instrumentation package monitored the overall behavior of the home and collected data vital to validating computational software for the manufactured housing industry. The tests were designed to approach the design load of the home without causing structural damage, thus allowing the behavior of the home to be accessed when the home was later exposed to high winds (to 80-mph). The data generally show near-linear initial system response with significant non-linear behavior as the applied loads increase. Load transfer across the marriage line is primarily compression. Racking, while present, is very small. Interface slip and shear displacement along the marriage line are nearly insignificant. Horizontal global displacements reached 0.6 inch. These tests were designed primarily to collect data necessary to calibrate a desktop analysis and design software tool, MHTool, under development at the Idaho National Laboratory specifically for manufactured housing. Currently available analysis tools are, for the most part, based on methods developed for “stick built” structures and are inappropriate for manufactured homes. The special materials utilized in manufactured homes, such as rigid adhesives used in the connection of the sheathing materials to the studs, significantly alter the behavior of manufactured homes under lateral loads. Previous full scale tests of laterally loaded manufactured homes confirm the contention that conventional analysis methods are not applicable. System behavior dominates the structural action of manufactured homes and its prediction requires a three dimensional analysis of the complete unit, including tiedowns. This project was

  11. A Naturally Occurring Recombinant Enterovirus Expresses a Torovirus Deubiquitinase.

    PubMed

    Shang, Pengcheng; Misra, Saurav; Hause, Ben; Fang, Ying

    2017-07-15

    identified a special case of cross-order recombination between enterovirus G (order Picornavirales) and torovirus (order Nidovirales). This naturally occurring recombination event may have broad implications for other picornaviral and/or nidoviral species. Importantly, we demonstrated that the exogenous ToV-PLP gene that was inserted into the EVG genome encodes a deubiquitinase/deISGylase and potentially suppresses host cellular innate immune responses. Our results provide insights into how a gain of function through genetic recombination, in particular cross-order recombination, may improve the ability of a virus to evade host immunity. Copyright © 2017 American Society for Microbiology.

  12. An assessment of natural radionuclides in water of Langat River estuary, Selangor

    NASA Astrophysics Data System (ADS)

    Hamzah, Zaini; Rosli, Tengku Nurliana Tuan Mohd; Saat, Ahmad; Wood, Ab. Khalik

    2014-02-01

    An estuary is an area that has a free connection with the open sea and it is a dynamic semi-enclosed coastal bodies. Ex-mining, aquaculture and industrial areas in Selangor are the sources of pollutants discharged into the estuary water. Radionuclides are considered as pollutants to the estuary water. Gamma radiations emitted by natural radionuclides through their decaying process may give impact to human. The radiological effect of natural radionuclides which are 226Ra, 228Ra, 40K, 238U and 232Th, were explored by determining the respective activity concentrations in filtered water along the Langat estuary, Selangor. Meanwhile, in- situ water quality parameters such as temperature, dissolve oxygen (DO), salinity, total suspended solid (TSS), pH and turbidity were measured by using YSI portable multi probes meter. The activity concentration of 226Ra, 228Ra and 40K were determined by using gamma-ray spectrometry with high-purity germanium (HPGe) detector. The activity concentrations of 226Ra, 228Ra and 40K in samples are in the range of 0.17 - 0.67 Bq/L, 0.16 - 0.97 Bq/L and 1.22 - 5.57 Bq/L respectively. On the other hand, the concentrations of uranium-238 and thorium-232 were determined by using Energy Dispersive X-ray Fluorescence Spectrometry (EDXRF). The thorium concentrations are between 0.17 ppm to 0.28 ppm and uranium concentrations were 0.25 ppm to 0.31 ppm. The results show activity concentrations of radionuclides are slightly high near the river estuary. The Radium Equivalent, Absorbed Dose Rate, External Hazard Index, and Annual Effective Dose of 226Ra, 228Ra and 40K are also studied.

  13. An assessment of natural radionuclides in water of Langat River estuary, Selangor

    SciTech Connect

    Hamzah, Zaini Rosli, Tengku Nurliana Tuan Mohd Saat, Ahmad Wood, Ab. Khalik

    2014-02-12

    An estuary is an area that has a free connection with the open sea and it is a dynamic semi-enclosed coastal bodies. Ex-mining, aquaculture and industrial areas in Selangor are the sources of pollutants discharged into the estuary water. Radionuclides are considered as pollutants to the estuary water. Gamma radiations emitted by natural radionuclides through their decaying process may give impact to human. The radiological effect of natural radionuclides which are {sup 226}Ra, {sup 228}Ra, {sup 40}K, {sup 238}U and {sup 232}Th, were explored by determining the respective activity concentrations in filtered water along the Langat estuary, Selangor. Meanwhile, in- situ water quality parameters such as temperature, dissolve oxygen (DO), salinity, total suspended solid (TSS), pH and turbidity were measured by using YSI portable multi probes meter. The activity concentration of {sup 226}Ra, {sup 228}Ra and {sup 40}K were determined by using gamma-ray spectrometry with high-purity germanium (HPGe) detector. The activity concentrations of {sup 226}Ra, {sup 228}Ra and {sup 40}K in samples are in the range of 0.17 - 0.67 Bq/L, 0.16 - 0.97 Bq/L and 1.22 - 5.57 Bq/L respectively. On the other hand, the concentrations of uranium-238 and thorium-232 were determined by using Energy Dispersive X-ray Fluorescence Spectrometry (EDXRF). The thorium concentrations are between 0.17 ppm to 0.28 ppm and uranium concentrations were 0.25 ppm to 0.31 ppm. The results show activity concentrations of radionuclides are slightly high near the river estuary. The Radium Equivalent, Absorbed Dose Rate, External Hazard Index, and Annual Effective Dose of {sup 226}Ra, {sup 228}Ra and {sup 40}K are also studied.

  14. The use of lichen (Canoparmelia texana) as biomonitor of atmospheric deposition of natural radionuclides from U-238 and Th-232 series

    NASA Astrophysics Data System (ADS)

    Leonardo, Lucio; Damatto, Sandra Regina; Mazzilli, Barbara Paci; Saiki, Mitiko

    2008-08-01

    Lichens have been used in studies of environmental pollution monitoring of various air pollutants, especially heavy metals. This paper aims to study the possibility of using this specimen for the assessment of radionuclides deposition in the vicinity of a nuclear research institute, Instituto de Pesquisas Energéticas e Nucleares (IPEN) located in São Paulo, Brazil. This Institute has as major activity to perform research in the field of the nuclear fuel cycle, and therefore deals with considerable amounts of natural radionuclides of the U and Th series. The activity of the naturally occurring radionuclides U-238, Ra-226, Ra-226 and Pb-210 was determined in samples of lichen (Canoparmelia texana) and soil collected at IPEN campus. The concentrations of Ra-228, Ra-226 and Pb-210 were determined by measuring alpha and beta gross counting in a gas flow proportional detector; U and Th were determined by neutron activation analysis. The values obtained varied from 164 Bq/kg to 864 Bq/kg, 13 Bq/kg to 50 Bq/kg, and from 287 Bq/kg to 730 Bq/kg for Ra-228, Ra-226 and Pb-210 respectively. For natural U and Th the values obtained varied from 1.2 Bq/kg to 162 Bq/kg and 1.84 Bq/kg to 5.17 Bq/kg respectively. The results obtained so far suggest that the Canoparmelia texana can be used as radionuclide monitor in the vicinity of nuclear installations.

  15. The use of lichen (Canoparmelia texana) as biomonitor of atmospheric deposition of natural radionuclides from U-238 and Th-232 series

    SciTech Connect

    Leonardo, Lucio; Damatto, Sandra Regina; Mazzilli, Barbara Paci; Saiki, Mitiko

    2008-08-07

    Lichens have been used in studies of environmental pollution monitoring of various air pollutants, especially heavy metals. This paper aims to study the possibility of using this specimen for the assessment of radionuclides deposition in the vicinity of a nuclear research institute, Instituto de Pesquisas Energeticas e Nucleares (IPEN) located in Sao Paulo, Brazil. This Institute has as major activity to perform research in the field of the nuclear fuel cycle, and therefore deals with considerable amounts of natural radionuclides of the U and Th series. The activity of the naturally occurring radionuclides U-238, Ra-226, Ra-226 and Pb-210 was determined in samples of lichen (Canoparmelia texana) and soil collected at IPEN campus. The concentrations of Ra-228, Ra-226 and Pb-210 were determined by measuring alpha and beta gross counting in a gas flow proportional detector; U and Th were determined by neutron activation analysis. The values obtained varied from 164 Bq/kg to 864 Bq/kg, 13 Bq/kg to 50 Bq/kg, and from 287 Bq/kg to 730 Bq/kg for Ra-228, Ra-226 and Pb-210 respectively. For natural U and Th the values obtained varied from 1.2 Bq/kg to 162 Bq/kg and 1.84 Bq/kg to 5.17 Bq/kg respectively. The results obtained so far suggest that the Canoparmelia texana can be used as radionuclide monitor in the vicinity of nuclear installations.

  16. Naturally Occurring Wound Healing Agents: An Evidence-Based Review.

    PubMed

    Karapanagioti, E G; Assimopoulou, A N

    2016-01-01

    Nature constitutes a pool of medicines for thousands of years. Nowadays, trust in nature is increasingly growing, as many effective medicines are naturally derived. Over the last decades, the potential of plants as wound healing agents is being investigated. Wounds and ulcers affect the patients' life quality and often lead to amputations. Approximately 43,000,000 patients suffer from diabetic foot ulcers worldwide. Annually, $25 billion are expended for the treatment of chronic wounds, with the number growing due to aging population and increased incidents of diabetes and obesity. Therefore a timely, orderly and effective wound management and treatment is crucial. This paper aims to systematically review natural products, mainly plants, with scientifically well documented wound healing activity, focusing on articles based on animal and clinical studies performed worldwide and approved medicinal products. Moreover, a brief description of the wound healing mechanism is presented, to provide a better understanding. Although a plethora of natural products are in vitro and in vivo evaluated for wound healing activity, only a few go through clinical trials and even fewer launch the market as approved medicines. Most of them rely on traditional medicine, indicating that ethnopharmacology is a successful strategy for drug development. Since only 6% of plants have been systematically investigated pharmacologically, more intensified efforts and emerging advancements are needed to exploit the potentials of nature for the development of novel medicines. This paper aims to provide a reliable database and matrix for thorough further investigation towards the discovery of wound healing agents.

  17. An overview of naturally occurring radioactive materials (NORM) in the petroleum industry

    SciTech Connect

    Smith, K.P.

    1992-12-01

    Oil and gas extraction and processing operations sometimes accumulate naturally occurring radioactive materials (NORM) at concentrations above normal in by-product waste streams. Results from NORM surveys indicate that radionuclide concentrations can be quite variable, ranging from undetectable to extremely high levels. To date, efforts to characterize the geographic distribution of NORM have been limited by poor statistical representation. In addition, the fate of NORM in the environment has not been fully defined, and few human health risk assessment have been conducted. Both the petroleum industry and regulators are becoming increasingly concerned about the presence of NORM. At present, most existing federal environmental regulations do not address oil and gas NORM, and only a few states have developed regulatory programs. Available data suggest that the occurrence of NORM (and associated health risks) is significant enough to warrant increased regulatory control. However, before these regulations can be developed, additional research is needed to (1) better characterize the occurrence and distribution of NORM throughout the industry, (2) quantify hazards posed by NORM to industry workers and the general public, and (3) develop effective waste treatment and minimization technologies that will lower the risk associated with NORM and reduce disposal costs.

  18. Construction of a naturally occurring radioactive material project in the BeAAT hazardous waste facilities.

    PubMed

    Abuahmad, H

    2015-06-01

    This paper does not necessarily reflect the views of the International Commission on Radiological Protection. Naturally occurring radioactive material (NORM) is produced during exploration and production operations of subsidiaries of the Abu Dhabi National Oil Company (ADNOC) in the United Arab Emirates, and accumulates in drilling tubulars, plant equipment, and components. These NORM hazardous wastes need to be managed in such a way that they do not damage human health and the environment. The primary radionuclides of concern in the oil and gas industries are radium-226 and radium-228. These radioisotopes are the decay products of uranium and thorium isotopes that are present in subsurface formations from which hydrocarbons are produced. While uranium and thorium are largely immobile, radium is slightly more soluble and may become mobilised in the fluid phases of the formation (International Association of Oil & Gas Producers, 2008). In order to treat and dispose of NORM waste products safely, ADNOC's subsidiary 'TAKREER' is developing a new facility, on behalf of all ADNOC subsidiaries, within the existing Central Environmental Protection Facilities (BeAAT) in Ruwais city. The NORM plant is envisaged to treat, handle, and dispose of NORM waste in the forms of scale, sludge, and contaminated equipment. The NORM treatment facility will cover activities such as decontamination, volume reduction, NORM handling, and concrete immobilisation of NORM waste into packages for designated landfilling.

  19. Regulatory Initiatives for Control and Release of Technologically Enhanced Naturally-Occurring Radioactive Materials

    SciTech Connect

    Egidi, P.V.

    1999-03-02

    Current drafts of proposed standards and suggested State regulations for control and release of technologically-enhanced naturally-occurring radioactive material (TENORM), and standards for release of volumetrically-contaminated material in the US are reviewed. These are compared to the recommendations of the International Atomic Energy Association (IAEA) Safety Series and the European Commission (EC) proposals. Past regulatory efforts with respect to TENORM in the US dealt primarily with oil-field related wastes. Currently, nine states (AK, GA, LA, MS, NM, OH, OR SC, TX) have specific regulations pertaining to TENORM, mostly based on uranium mill tailings cleanup criteria. The new US proposals are dose- or risk-based, as are the IAEA and EC recommendations, and are grounded in the linear no threshold hypothesis (LNT). TENORM wastes involve extremely large volumes, particularly scrap metal and mine wastes. Costs to control and dispose of these wastes can be considerable. The current debate over the validity of LNT at low doses and low dose rates is particularly germane to this discussion. Most standards setting organizations and regulatory agencies base their recommendations on the LNT. The US Environmental Protection Agency has released a draft Federal Guidance Report that recommends calculating health risks from low-level exposure to radionuclides based on the LNT. However, some scientific and professional organizations are openly questioning the validity of LNT and its basis for regulations, practices, and costs to society in general. It is not clear at this time how a non-linear regulatory scheme would be implemented.

  20. Naturally occurring anti-cancer agents targeting EZH2.

    PubMed

    Shahabipour, Fahimeh; Caraglia, Michele; Majeed, Muhammed; Derosa, Giuseppe; Maffioli, Pamela; Sahebkar, Amirhossein

    2017-03-18

    Natural products are considered as promising tools for the prevention and treatment of cancer. The enhancer of zeste homolog 2 (EZH2) is a histone methyltransferase unit of polycomb repressor complexes such as PRC2 complex that has oncogenic roles through interference with growth and metastatic potential. Several agents targeting EZH2 has been discovered but they often induce side effects in clinical trials. Recently, EZH2 has emerged as a potential target of natural products with documented anti-cancer effects and this discloses a new scenario for the development of EZH2 inhibitory strategies with agents with low cytotoxic detrimental effects. In fact, several natural products such as curcumin, triptolide, ursolic acid, sulforaphane, davidiin, tanshindiols, gambogic acid, berberine and Alcea rosea have been shown to serve as EZH2 modulators. Mechanisms like inhibition of histone H3K4, H3K27 and H3K36 trimethylation, down-regulation of matrix metalloproteinase expression, competitive binding to the S-adenosylmethionine binding site of EZH2 and modulation of tumor-suppressive microRNAs have been demonstrated to mediate the EZH2-inhibitory activity of the mentioned natural products. This review summarizes the pathways that are regulated by various natural products resulting in the suppression of EZH2, and provides a plausible molecular mechanism for the putative anti-cancer effects of these compounds.

  1. Environmental impact of natural radionuclides from a coal-fired power plant in Spain.

    PubMed

    Charro, Elena; Peña, Víctor

    2013-01-01

    This paper is a study of the radiological impact of a coal-fired power plant in Spain. Activity concentrations of six natural radionuclides were determined in coal, ash, mine wastes and sediments by gamma-ray spectrometry. The average activity concentrations of (238)U, (226)Ra, (224)Ra, (210)Pb, (232)Th and (40)K in coal were 24, 30, 28, 41, 23 and 242 Bq kg(-1)  and in ash were 103, 128, 101, 124, 88 and 860 Bq kg(-1), respectively. The enrichment factor, radium equivalent activity and alpha index in the ash sample have been estimated. For the five waste pile samples, the absorbed dose rate was higher than the world average dose rate (60 nGy h(-1)). The dependence of radionuclide concentration on the grain size of nine sediments was also studied. The analysis of the radionuclides in waste and sediment samples will demonstrate the distribution and mobility of these elements through the environment, where a potential risk of contamination can be detected.

  2. Some geological characteristics in a regolith-limey shale rock profile through natural radionuclides distribution.

    PubMed

    Ferreira, Ademar de O; Bastos, Rodrigo O; Appoloni, Carlos R

    2010-09-01

    The objective of this work is to study some geological characteristics in a regolith-rock profile by analyzing the distribution of natural radionuclides along the profile by high resolution gamma ray spectrometry. The concentrations of radionuclides reflect some mineralogical characteristics of the rock matrix and also more recent events, such as weathering and erosion. The samples were collected in an abandoned limestone mine, in the city of Sapopema, Paraná State, Brazil. The stratigraphy is represented by an alternation of decimetric limestone layers, bituminous shale and some rhythmite layers. The ratios eTh/K obtained for all samples of the studied profile have equivalent values, indicating similar mineralogical characteristics of their detritic components. The ratio eTh/eU corroborates the fact that regolith samples belong to a much more oxidized environment, favoring the leaching of uranium. These results show that the measurement of radionuclide distribution in rocks and soils may be an important tool for the analysis of geological characteristics, such as mineralogy and oxidizing conditions.

  3. The timing of the age at which natural menopause occurs.

    PubMed

    Gold, Ellen B

    2011-09-01

    The timing of natural menopause is a clinically important indicator of longevity and risk of morbidity and mortality. Demographic, menstrual, reproductive, familial, genetic, and lifestyle factors seem to be important in this timing. Smoking, lower parity and poor socioeconomic status are associated with earlier menopause. However, a number of relationships have been inconsistent; others remain largely unexplored. Much remains to be learned about factors that affect follicular atresia and the onset and duration of perimenopause and the timing of the natural menopause. Knowledge about these relationships offers women and their health care providers enhanced understanding and choices to deal with menopause.

  4. Overview of naturally occurring Earth materials and human health concerns

    NASA Astrophysics Data System (ADS)

    Ernst, W. G.

    2012-10-01

    The biosphere and the Earth's critical zone have maintained a dynamic equilibrium for more than 3.5 billion years. Except for solar energy, almost all terrestrial substances necessary for life have been derived from near-surface portions of the land, hydrosphere, and atmosphere. If aggregate biological activities are less than the rate of nutrient supply and/or resource renewal, sustained population growth is possible. Where the replenishment rate of a life-sustaining Earth material is finite, usage may reach a condition of dynamic equilibrium in which biological consumption equals but on average cannot exceed the overall supply. Although large, most natural resources are present in finite abundances; for such commodities, excessive present-day human utilization reduces future availability, and thus the ultimate planetary carrying capacity for civilization. Intensive use of Earth materials has enhanced the quality of life, especially in the developed nations. Still, natural background levels, and Earth processes such as volcanic eruptions, as well as human activities involving agriculture, construction, and the extraction, refining, and transformation of mineral resources have led to harmful side effects involving environmental degradation and public health hazards. Among naturally and anthropogenically induced risks are bioaccessible airborne dusts and gases, soluble pollutants in agricultural, industrial, and residential waters, and toxic chemical species in foods and manufactured products. At appropriate levels of ingestion, many Earth materials are necessary for existence, but underdoses and overdoses have mild to serious consequences for human health and longevity. This overview briefly sketches several natural resource health hazards. Included are volcanic ash + aerosols + gases, mineral dusts, non-volcanic aerosols + nanoparticles, asbestos + fibrous zeolites, arsenic, fluorine, iodine, uranium + thorium + radium + radon + polonium, selenium, mercury, copper

  5. The Frequency, Nature, and Effects of Naturally Occurring Appearance-Focused Social Comparisons

    ERIC Educational Resources Information Center

    Leahey, Tricia M.; Crowther, Janis H.; Mickelson, Kristin D.

    2007-01-01

    This research examined the effects of naturally occurring appearance-focused social comparisons on women's affect, body satisfaction, and weight-related cognitions. During their daily activities, women reporting body dissatisfaction (n = 53) and women reporting body satisfaction (n = 34) recorded their reactions to comparison information.…

  6. The nature of the chromophore responsible for naturally occurring fluorescence in mouse skin.

    PubMed

    Weagle, G; Paterson, P E; Kennedy, J; Pottier, R

    1988-11-01

    Normal mouse skin has a prominent fluorescence peak at 674 nm. Fluorescence emission and fluorescence excitation spectroscopy, carried out both in vitro and in vivo, led to the conclusion that the chromophore(s) responsible for this naturally occurring fluorescence is/are pheophorbide a and/or pheophytin a, degradation products of chlorophyll a that are derived from the mouse food.

  7. Shear wave filtering in naturally-occurring Bouligand structures.

    PubMed

    Guarín-Zapata, Nicolás; Gomez, Juan; Yaraghi, Nick; Kisailus, David; Zavattieri, Pablo D

    2015-09-01

    Wave propagation was investigated in the Bouligand-like structure from within the dactyl club of the stomatopod, a crustacean that is known to smash their heavily shelled preys with high accelerations. We incorporate the layered nature in a unitary material cell through the propagator matrix formalism while the periodic nature of the material is considered via Bloch boundary conditions as applied in the theory of solid state physics. Our results show that these materials exhibit bandgaps at frequencies related to the stress pulse generated by the impact of the dactyl club to its prey, and therefore exhibiting wave filtering in addition to the already known mechanisms of macroscopic isotropic behavior and toughness. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  8. First empirical evidence of naturally occurring androgenesis in vertebrates.

    PubMed

    Morgado-Santos, Miguel; Carona, Sara; Vicente, Luís; Collares-Pereira, Maria João

    2017-05-01

    Androgenesis among vertebrates is considered a rare phenomenon, with some cases reported so far, but linked to experiments involving gamete manipulation (artificial androgenesis). Herein, we report the first empirical evidence of the natural occurrence of spontaneous androgenesis in a vertebrate, the Squalius alburnoides allopolyploid complex. A genetically screened random sample of a natural population was allowed to reproduce in an isolated pond without any human interference, and the viable offspring obtained was later analysed for paternity. Both nuclear and mitochondrial markers showed that the only allodiploid fish found among all the allotriploid offspring was androgenetically produced by an allodiploid male. This specimen had no female nuclear genomic input, and the sequence of the mitochondrial fragment examined differed from that of the male progenitor, matching one of the parental females available in the pond, probably the mother. The possible role of androgenesis in the reproductive dynamics of this highly successful vertebrate complex is discussed.

  9. Interactions between plasma proteins and naturally occurring polyphenols.

    PubMed

    Li, Min; Hagerman, Ann E

    2013-05-01

    The plant natural products known as polyphenols are found at micronutrient levels in fruits, vegetables, and plant-based beverages such as wine, tea, coffee and cocoa. Consumption of a fruit- and vegetable-rich diet, the "Mediterranean diet", has been epidemiologically related to health benefits especially for chronic diseases including diabetes, cardiovascular disease, and Alzheimer's disease. The abundance of polyphenols in plant-rich diets, and the potent bioactivities of polyphenols, provide indirect evidence for a role for polyphenols in maintaining good health. However, molecular mechanisms for therapeutic or preventative activity have not been demonstrated in vivo. We summarize the chemical classes of natural polyphenols, their bioactivities and bioavailability and metabolism. Because many polyphenols bind protein, we focus on the potential of protein binding to mediate the health-related effects of polyphenols. We discuss interactions with plasma proteins as the first target organ past the digestive tract for these orally-ingested compounds.

  10. Going Wild: Lessons from Naturally Occurring T-Lymphotropic Lentiviruses

    PubMed Central

    VandeWoude, Sue; Apetrei, Cristian

    2006-01-01

    Over 40 nonhuman primate (NHP) species harbor species-specific simian immunodeficiency viruses (SIVs). Similarly, more than 20 species of nondomestic felids and African hyenids demonstrate seroreactivity against feline immunodeficiency virus (FIV) antigens. While it has been challenging to study the biological implications of nonfatal infections in natural populations, epidemiologic and clinical studies performed thus far have only rarely detected increased morbidity or impaired fecundity/survival of naturally infected SIV- or FIV-seropositive versus -seronegative animals. Cross-species transmissions of these agents are rare in nature but have been used to develop experimental systems to evaluate mechanisms of pathogenicity and to develop animal models of HIV/AIDS. Given that felids and primates are substantially evolutionarily removed yet demonstrate the same pattern of apparently nonpathogenic lentiviral infections, comparison of the biological behaviors of these viruses can yield important implications for host-lentiviral adaptation which are relevant to human HIV/AIDS infection. This review therefore evaluates similarities in epidemiology, lentiviral genotyping, pathogenicity, host immune responses, and cross-species transmission of FIVs and factors associated with the establishment of lentiviral infections in new species. This comparison of consistent patterns in lentivirus biology will expose new directions for scientific inquiry for understanding the basis for virulence versus avirulence. PMID:17041142

  11. Migration behavior of naturally occurring radionuclides at the Nopal I uranium deposit, Chihuahua, Mexico

    NASA Astrophysics Data System (ADS)

    Prikryl, James D.; Pickett, David A.; Murphy, William M.; Pearcy, English C.

    1997-04-01

    Oxidation of pyrite at the Nopal I uranium deposit, Peña Blanca district, Chihuahua, Mexico has resulted in the formation of Fe-oxides/hydroxides. Anomalous U concentrations (i.e. several hundred to several thousand ppm) measured in goethite, hematite, and amorphous Fe-oxyhydroxides in a major fracture that crosscuts the deposit and the absence of U minerals in the fracture suggest that U was retained during secondary mineral growth or sorbed on mineral surfaces. Mobilization and transport of U away from the deposit is suggested by decreasing U concentrations in fracture-infilling materials and in goethite and hematite with distance from the deposit. Greater than unity {234U}/{238U} activity ratios measured in fracture-infilling materials indicate relatively recent ( < 1 Ma) U uptake from fluids that carried excess 234U. Systematic decreases in {234U}/{238U} activity ratios of fracture materials with distance from the deposit suggest a multistage mobilization process, such as remobilization of U from 234U-enriched infill minerals or differential or diminished transport of U-bearing solutions containing excess 234U.

  12. Groundwater flow system in the valley of Toluca, Mexico: an assay of natural radionuclide specific activities.

    PubMed

    Segovia, N; Tamez, E; Peña, P; Carrillo, J; Acosta, E; Armienta, M A; Iturbe, J L

    1999-03-01

    Natural radionuclides and physicochemical parameters have been evaluated in groundwater samples from boreholes belonging to the drinking water supply system of the Toluca City, Mexico. The results obtained for radon and radium, together with the physicochemical parameters of the studied samples, indicate a fast and efficient recharge pattern. The presence of a local and a regional groundwater flows was also observed. The local flow belongs to shallower water, recognized by its low radon content and dissolved ions, as compared with the regional, deeper groundwater flow with a longer residence time.

  13. Estimation of annual effective dose due to ingestion of natural radionuclides in foodstuffs and water at a proposed uranium mining site in India.

    PubMed

    Giri, Soma; Jha, V N; Singh, Gurdeep; Tripathi, R M

    2013-12-01

    To study the distribution of (210)Po, (226)Ra, (230)Th and U(nat) (naturally occurring radioisotopes of uranium [(234)U, (235)U and (238)U]) in food and water around the Bagjata uranium mining area in India. Radionuclides were analyzed in food samples of plant and animal origin after acid digestion. Intake and ingestion dose of the radionuclides were estimated. (210)Po, (226)Ra, (230)Th and U(nat) in all the dietary components ranged widely from < 0.2-36, < 0.02-1.58, < 0.01-2.8 and < 0.017-0.39 Bqkg(-1), respectively. The range of (226)Ra and U(nat) in water was < 3.5-206 and < 12.6-693 mBql(-1), respectively. The intake of radionuclides considering food and water was calculated to be 760 BqY(-1) while the ingestion dose was 601 μSvY(-1). The estimated doses reflect the natural background dose via route of ingestion, which is below the 1 mSvY(-1) limit set by the International Commission on Radiological Protection (ICRP). However, the doses are more than the dose constraint of 300 μSvY(-1) as suggested by the ICRP for members of the public for planned disposal of long-lived radioactive waste. The study confirms that current levels of radionuclides do not pose significant radiological risk to the local inhabitants, but they need close investigation in the near future.

  14. Virological and serological findings in dogs with naturally occurring distemper.

    PubMed

    Elia, Gabriella; Camero, Michele; Losurdo, Michele; Lucente, Maria Stella; Larocca, Vittorio; Martella, Vito; Decaro, Nicola; Buonavoglia, Canio

    2015-03-01

    Canine distemper virus (CDV) is the cause of a severe and highly contagious disease in dogs. The unpredictable and variable course of CDV-related disease may hamper correct diagnosis of infection and makes it crucial the collection of samples suitable for laboratory confirmation. In the present study we were able to follow the disease in two dogs infected naturally, collecting different biological matrices during the entire period of infection. By real time RT-PCR, viral RNA was detected and quantified, suggesting that urine and rectal swabs would be useful for ante-mortem diagnosis of distemper in dogs, regardless of the clinical stage and form of the illness.

  15. A naturally-occurring 'cold earth' spot in Northern China.

    PubMed

    Niu, Fujun; Cheng, Guodong; Niu, Yonghong; Zhang, Mingyi; Luo, Jing; Lin, Zhanju

    2016-09-29

    Permafrost is determined to a large extent by the Earth's surface temperature, therefore it distributes mainly in high altitude and latitude regions. However, stable, warm (about -1 °C) permafrost occurs within a scree slope in northern China that is more than 600 km south of the southernmost limit of latitudinal permafrost on the Eurasian Continent. It is at an elevation of only 900 m above sea level (ASL). The area has a mean annual air temperature (MAAT) of 6 to 8 °C. Thermal processes of the scree slope, investigated through field monitoring and numerical simulation, showed that the permafrost is caused by winter air convection within the porous rock deposits and is stable as air convection does not occur in summer time. The deposit is covered by a 30-cm-thick peaty soil layer dated (carbon C-14) to between 1,000 to 1,600 years ago. The layer also contributes to the permafrost's existence due to the peat's thermal conductivity offset when frozen and thawed. The existence of permafrost under such warm climatic conditions confirms the effectiveness of using crushed rock layer as basement or slope cover to protect the warm permafrost subgrade of the recently-constructed Qinghai-Tibet Railway (QTR), even under the predicted climate warming conditions.

  16. Polyomavirus and Naturally Occuring Neuroglial Tumors in Raccoons (Procyon Lotor).

    PubMed

    Pesavento, Patricia A; Brostoff, Terza; Church, Molly E; Dela Cruz, Florante N; Woolard, Kevin D

    2016-01-01

    Polyomavirus (PyV) infections are widespread in human populations and, although generally associated with silent persistence, rarely cause severe disease. Among diseases convincingly associated with natural PyV infections of humans, there are remarkably different tissue tropisms and outcomes, including progressive multifocal leukoencephalopathy, transient or progressive nephropathy, and cancer. The variable character and unpredictable outcomes of infection attest to large gaps in our basic understanding of PyV biology. In particular, the rich history of research demonstrating the oncogenic potential of PyVs in laboratory animals begs the question of why cancer is not more often associated with infection. Raccoon polyomavirus (RacPyV), discovered in 2010, is consistently identified in neuroglial tumors in free-ranging raccoons in the western United States. Exposure to RacPyV is widespread, and RacPyV is detected in tissues of raccoons without tumors. Studying the relationship of RacPyV with its natural host is a unique opportunity to uncover cogent cellular targets and protein interactions between the virus and its host. Our hypothesis is that RacPyV, as an intact episome, alters cellular pathways within neural progenitor cells and drives oncogenesis.

  17. Structures and Properties of Naturally Occurring Polyether Antibiotics

    PubMed Central

    Rutkowski, Jacek; Brzezinski, Bogumil

    2013-01-01

    Polyether ionophores represent a large group of natural, biologically active substances produced by Streptomyces spp. They are lipid soluble and able to transport metal cations across cell membranes. Several of polyether ionophores are widely used as growth promoters in veterinary. Polyether antibiotics show a broad spectrum of bioactivity ranging from antibacterial, antifungal, antiparasitic, antiviral, and tumour cell cytotoxicity. Recently, it has been shown that some of these compounds are able to selectively kill cancer stem cells and multidrug-resistant cancer cells. Thus, they are recognized as new potential anticancer drugs. The biological activity of polyether ionophores is strictly connected with their molecular structure; therefore, the purpose of this paper is to present an overview of their formula, molecular structure, and properties. PMID:23586016

  18. Structures and properties of naturally occurring polyether antibiotics.

    PubMed

    Rutkowski, Jacek; Brzezinski, Bogumil

    2013-01-01

    Polyether ionophores represent a large group of natural, biologically active substances produced by Streptomyces spp. They are lipid soluble and able to transport metal cations across cell membranes. Several of polyether ionophores are widely used as growth promoters in veterinary. Polyether antibiotics show a broad spectrum of bioactivity ranging from antibacterial, antifungal, antiparasitic, antiviral, and tumour cell cytotoxicity. Recently, it has been shown that some of these compounds are able to selectively kill cancer stem cells and multidrug-resistant cancer cells. Thus, they are recognized as new potential anticancer drugs. The biological activity of polyether ionophores is strictly connected with their molecular structure; therefore, the purpose of this paper is to present an overview of their formula, molecular structure, and properties.

  19. Serum concentration of sialic acids in naturally occurring ovine babesiosis.

    PubMed

    Esmaeilnejad, Bijan; Tavassoli, Mousa; Asri-Rezaei, Siamak; Dalir-Naghadeh, Bahram; Abtahi Froushani, Seyyed Meysam; Arjmand, Jafar; Golabi, Mostafa

    2014-10-01

    This study is designated to assess the effect of the severity of Babesia ovis infection on sialic acid concentration in blood sera in naturally infected sheep. Infected animals (diseased group) comprised 38 Iranian fat-tailed sheep, about 1-3 years old, naturally infected with B. ovis, divided into four subgroups with respect to parasitemia rates (low 0.1-0.3 %, moderate 0.4-0.9 %, high 1-2.5 %, and very high >2.5 %). The parasitological diagnosis was confirmed using PCR analysis. As a control group, ten clinically healthy sheep reared under the same management and environmental conditions were also sampled. Hematological parameters and the concentrations of total sialic acid (TSA), lipid-bound sialic acid (LBSA), and protein-bound sialic acid (PBSA) were measured in both groups. Compared to controls, sialic acid concentrations showed significant increase (p < 0.05) in infected sheep. Parasitemia rate was positively correlated with sialic acid concentrations. This study demonstrated that B. ovis infection induced marked and persistent elevations of serum sialic acid concentrations. It seems that increase of serum sialic acid concentrations during parasitemia alter receptor-ligand interactions, which are known to play important role in immune response. Furthermore, sialic acid would indirectly inhibit the action of leukocytes and consequently promote the evasion of the immune response and persistence of the parasite in the host. This factor could influence the parasite-host cell adhesion, but further detailed biochemical investigations are needed to precisely explain the exact role of sialic acid in invasion process of the parasite to the host cells.

  20. Natural attenuation of metals and radionuclides -- An overview of the Sandia/DOE approach

    SciTech Connect

    Waters, R.D.; Brady, P.V.; Borns, D.J.

    1998-02-01

    Sandia National Laboratories is developing guidelines that outline the technical basis for relying on natural attenuation for the remediation of metals and radionuclide-contaminated soils and groundwaters at US Department of Energy (DOE) sites for those specific cases where natural processes are effective at ameliorating soil and groundwater toxicity. Remediation by monitored natural attenuation (MNA) requires a clear identification of the specific reaction(s) by which contaminant levels are made less available as well as considerable long-term monitoring. Central to MNA is the development of a conceptual model describing the biogeochemical behavior of contaminant(s) in the subsurface. The conceptual model will be used to make testable predictions of contaminant availability over time. In many cases, comparison between this prediction and field measurements will provide the test of whether MNA is to be implemented. As a result, development of the conceptual model should guide site characterization activities as well as long-term monitoring.

  1. Distribution of natural radionuclides in the production and use of phosphate fertilizers in Brazil.

    PubMed

    Saueia, C H R; Mazzilli, B P

    2006-01-01

    The Brazilian phosphate fertilizer is obtained by wet reaction of igneous phosphate rock with concentrated sulphuric acid, giving as final product, phosphoric acid and dehydrated calcium sulphate (phosphogypsum) as by-products. Phosphoric acid is the starting material for triple superphosphate (TSP), single superphosphate (SSP), monoammonium phosphate (MAP) and diammonium phosphate (DAP). The phosphate rock used as raw material presents in its composition radionuclides of the U and Th natural series. Taking this into account, the main aim of this paper is to evaluate the fluxes of natural radionuclides and radioactive disequilibria involved in the Brazilian industrial process of phosphoric acid production; to determine the content of radioactivity in several commercial fertilizers produced by this industry; to estimate their radiological impact in crop soils and the long term exposure due to their application. Radiological characterization of phosphate rock, phosphogypsum and phosphate fertilizers was performed by alpha and gamma spectrometry. The fertilizer samples, which are derived directly from phosphoric acid, MAP and DAP, presented in their composition low activity concentrations for 226Ra, 228Ra and 210Pb. As for U and Th, the concentrations found in MAP and DAP are more significant, up to 822 and 850Bqkg(-1), respectively. SSP and TSP, which are obtained by mixing phosphoric acid with different amounts of phosphate rock, presented higher concentrations of radionuclides, up to 1158Bqkg(-1) for (238)U, 1167Bqkg(-1) for (234)U, 1169Bqkg(-1) for 230Th, 879Bqkg(-1) for 226Ra, 1255Bqkg(-1) for 210Pb, 521Bqkg(-1) for 232Th, 246Bqkg(-1) for 228Ra and 302Bqkg(-1) for 228Th. Long term exposure due to successive fertilizer applications was evaluated. Internal doses due to the application of phosphate fertilizer for 10, 50 and 100 years were below 1mSvy(-1), showing that the radiological impact of such practice is negligible.

  2. Evidence of sublaminar drag naturally occurring in a curved pipe

    SciTech Connect

    Noorani, A.; Schlatter, P.

    2015-03-15

    Steady and unsteady flows in a mildly curved pipe for a wide range of Reynolds numbers are examined with direct numerical simulation. It is shown that in a range of Reynolds numbers in the vicinity of Re{sub b} ≈ 3400, based on bulk velocity and pipe diameter, a marginally turbulent flow is established in which the friction drag naturally reduces below the laminar solution at the same Reynolds number. The obtained values for friction drag for the laminar and turbulent (sublaminar) flows turn out to be in excellent agreement with experimental measurements in the literature. Our results are also in agreement with Fukagata et al. [“On the lower bound of net driving power in controlled duct flows,” Phys. D 238, 1082 (2009)], as the lower bound of net power required to drive the flow, i.e., the pressure drop of the Stokes solution, is still lower than our marginally turbulent flow. A large-scale traveling structure that is thought to be responsible for that behaviour is identified in the instantaneous field. This mode could also be extracted using proper orthogonal decomposition. The effect of this mode is to redistribute the mean flow in the circular cross section which leads to lower gradients at the wall compared to the laminar flow.

  3. Evidence of sublaminar drag naturally occurring in a curved pipe

    NASA Astrophysics Data System (ADS)

    Noorani, A.; Schlatter, P.

    2015-03-01

    Steady and unsteady flows in a mildly curved pipe for a wide range of Reynolds numbers are examined with direct numerical simulation. It is shown that in a range of Reynolds numbers in the vicinity of Reb ≈ 3400, based on bulk velocity and pipe diameter, a marginally turbulent flow is established in which the friction drag naturally reduces below the laminar solution at the same Reynolds number. The obtained values for friction drag for the laminar and turbulent (sublaminar) flows turn out to be in excellent agreement with experimental measurements in the literature. Our results are also in agreement with Fukagata et al. ["On the lower bound of net driving power in controlled duct flows," Phys. D 238, 1082 (2009)], as the lower bound of net power required to drive the flow, i.e., the pressure drop of the Stokes solution, is still lower than our marginally turbulent flow. A large-scale traveling structure that is thought to be responsible for that behaviour is identified in the instantaneous field. This mode could also be extracted using proper orthogonal decomposition. The effect of this mode is to redistribute the mean flow in the circular cross section which leads to lower gradients at the wall compared to the laminar flow.

  4. Naturally Occurring Off-Switches for CRISPR-Cas9.

    PubMed

    Pawluk, April; Amrani, Nadia; Zhang, Yan; Garcia, Bianca; Hidalgo-Reyes, Yurima; Lee, Jooyoung; Edraki, Alireza; Shah, Megha; Sontheimer, Erik J; Maxwell, Karen L; Davidson, Alan R

    2016-12-15

    CRISPR-Cas9 technology would be enhanced by the ability to inhibit Cas9 function spatially, temporally, or conditionally. Previously, we discovered small proteins encoded by bacteriophages that inhibit the CRISPR-Cas systems of their host bacteria. These "anti-CRISPRs" were specific to type I CRISPR-Cas systems that do not employ the Cas9 protein. We posited that nature would also yield Cas9 inhibitors in response to the evolutionary arms race between bacteriophages and their hosts. Here, we report the discovery of three distinct families of anti-CRISPRs that specifically inhibit the CRISPR-Cas9 system of Neisseria meningitidis. We show that these proteins bind directly to N. meningitidis Cas9 (NmeCas9) and can be used as potent inhibitors of genome editing by this system in human cells. These anti-CRISPR proteins now enable "off-switches" for CRISPR-Cas9 activity and provide a genetically encodable means to inhibit CRISPR-Cas9 genome editing in eukaryotes. VIDEO ABSTRACT. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Naturally Occurring Variants of the Dysglycemic Peptide Pancreastatin

    PubMed Central

    Allu, Prasanna K. R.; Chirasani, Venkat R.; Ghosh, Dhiman; Mani, Anitha; Bera, Amal K.; Maji, Samir K.; Senapati, Sanjib; Mullasari, Ajit S.; Mahapatra, Nitish R.

    2014-01-01

    Pancreastatin (PST), a chromogranin A-derived peptide, is a potent physiological inhibitor of glucose-induced insulin secretion. PST also triggers glycogenolysis in liver and reduces glucose uptake in adipocytes and hepatocytes. Here, we probed for genetic variations in PST sequence and identified two variants within its functionally important carboxyl terminus domain: E287K and G297S. To understand functional implications of these amino acid substitutions, we tested the effects of wild-type (PST-WT), PST-287K, and PST-297S peptides on various cellular processes/events. The rank order of efficacy to inhibit insulin-stimulated glucose uptake was: PST-297S > PST-287K > PST-WT. The PST peptides also displayed the same order of efficacy for enhancing intracellular nitric oxide and Ca2+ levels in various cell types. In addition, PST peptides activated gluconeogenic genes in the following order: PST-297S ≈ PST-287K > PST-WT. Consistent with these in vitro results, the common PST variant allele Ser-297 was associated with significantly higher (by ∼17 mg/dl, as compared with the wild-type Gly-297 allele) plasma glucose level in our study population (n = 410). Molecular modeling and molecular dynamics simulations predicted the following rank order of α-helical content: PST-297S > PST-287K > PST-WT. Corroboratively, circular dichroism analysis of PST peptides revealed significant differences in global structures (e.g. the order of propensity to form α-helix was: PST-297S ≈ PST-287K > PST-WT). This study provides a molecular basis for enhanced potencies/efficacies of human PST variants (likely to occur in ∼300 million people worldwide) and has quantitative implications for inter-individual variations in glucose/insulin homeostasis. PMID:24338022

  6. Bacterial quorum sensing and interference by naturally occurring biomimics.

    PubMed

    McDougald, Diane; Rice, Scott A; Kjelleberg, Staffan

    2007-01-01

    Bacteria are able to coordinate gene expression as a community through the secretion and detection of signalling molecules so that the members of the community can simultaneously express specific behaviours. This mechanism of regulation of behaviour appears to be a key trait for adaptation to specific environments and has been shown to regulate a variety of important phenotypes, from virulence factor production to biofilm formation to symbiosis related behaviours such as bioluminescence. The ability to communicate and communally regulate gene expression is hypothesised to have evolved as a way for organisms to delay expression of phenotypes until numerical supremacy is reached. For example, in the case of infection, if an invading microorganism were to express virulence factors too early, the host may be able to mount a successful defence and repel the invaders. There is growing evidence that bacterial quorum sensing (QS) systems are involved in cross-kingdom signalling with eukaryotic organisms and that eukaryotes are capable of actively responding to bacteria in their environment by detecting and acting upon the presence of these signalling molecules. Likewise, eukaryotes produce compounds that can interfere with QS systems in bacteria by acting as agonists or antagonists. An exciting new field of study, biomimetics, takes inspiration from nature's models and attempts to design solutions to human problems, and biomimics of QS systems may be one such solution. This article presents the acylated homoserine lactone and autoinducer 2 QS systems in bacteria, the means of intercepting or interfering with bacterial QS systems evolved by eukaryotes, and the rational design of synthetic antagonists.

  7. Naturally-occurring dimers of flavonoids as anticarcinogens.

    PubMed

    Mercader, Andrew G; Pomilio, Alicia B

    2013-10-01

    Biflavonoids are dimers of flavonoid moieties linked by a C-C or C-O-C bond. Simple, complex, rearranged, natural and ketalized Diels-Alder adducts, benzofuran derivatives, and spirobiflavonoids are some of the structural groups of biflavonoids. These compounds are mainly distributed in the Gymnosperms, Angiosperms (monocots and dicots), ferns (Pteridophyta), and mosses (Bryophyta). Biflavonoids have shown a variety of biological activities, including anticancer, antibacterial, antifungal, antiviral, antiinflammatory, analgesic, antioxidant, vasorelaxant, anticlotting, among others. This work is focused on probably the most potentially relevant biological activity of biflavonoids, the anticancer activity and the involved mechanisms of action, such as induction of apoptosis [inhibition of cyclic nucleotide phosphodiesterases; effects on NF-κB family of transcription factors; activation of caspase(s); inhibition effects on bcl-2 expression, and upregulation of p53 and caspase-3 gene expression]; inhibition of angiogenesis [anti-proliferative effects; activation of Rho-GTPases and ERK signaling pathways; inhibition of FASN activity]; inhibition of pre-mRNA splicing; inhibition of human DNA topoisomerases I and II-α; anti-inflammatory/ immunoregulatory effects [inhibition of XO; inhibition of proinflammatory enzymes, such as PLA2 and COX; effects on cytokines mediated COX-2 and iNOS expression]; modulation of immune response; inhibition of protein tyrosine phosphorylation; antioxidant and analgesic activities in relation to the anticarcinogen behavior. For that reason the structures and anticarcinogenic activities of 83 biflavonoids are thoroughly discussed. The results of this work indicate that biflavonoids strongly affect the cancer cells with little effect on normal cell proliferation, suggesting a therapeutic potential against cancer.

  8. Naturally occurring and synthetic peptides acting on nicotinic acetylcholine receptors.

    PubMed

    Kasheverov, Igor E; Utkin, Yuri N; Tsetlin, Victor I

    2009-01-01

    Nicotinic acetylcholine receptors (nAChRs) are pentameric membrane-bound proteins belonging to the large family of ligand-gated ion channels. nAChRs possess various binding sites which interact with compounds of different chemical nature, including peptides. Historically first peptides found to act on nAChR were synthetic fragments of snake alpha-neurotoxins, competitive receptor antagonists. Later it was shown that fragments of glycoprotein from rabies virus, having homology to alpha-neurotoxins, and polypeptide neurotoxins waglerins from the venom of Wagler's pit viper Trimeresurus (Tropidolaemus) wagleri bind in a similar way, waglerins being efficient blockers of muscle-type nAChRs. Neuropeptide substance P appears to interact with the channel moiety of nAChR. beta-Amyloid, a peptide forming senile plaques in Alzheimer's disease, also can bind to nAChR, although the mode of binding is still unclear. However, the most well-studied peptides interacting with the ligand-binding sites of nAChRs are so-called alpha-conotoxins, peptide neurotoxins from marine snails of Conus genus. First alpha-conotoxins were discovered in the late 1970s, and now it is a rapidly growing family due to isolation of peptides from multiple Conus species, as well as to cloning, and chemical synthesis of new analogues. Because of their unique selectivity towards distinct nAChR subtypes, alpha-conotoxins became valuable tools in nAChR research. Recent X-ray structures of alpha-conotoxin complexes with acetylcholine-binding protein, a model of nAChR ligand-binding domains, revealed the details of the nAChR ligand-binding sites and provided the basis for design of novel ligands.

  9. Fractionation of natural radionuclides in soils from the vicinity of a former uranium mine Zirovski vrh, Slovenia.

    PubMed

    Strok, Marko; Smodis, Borut

    2010-01-01

    As a result of former uranium mining and milling activities at Zirovski vrh, Slovenia, 0.6 million tons of uranium mill tailings (UMT) were deposited onto a nearby waste pile Borst. Resulting enhanced levels of natural radionuclides in UMT could pose threat for the surrounding environment. Therefore, sequential extraction protocol was performed to assess mobility and bioavailability of (238)U, (234)U, (230)Th and (226)Ra in soils from the waste pile and its surrounding. The radionuclides associated with exchangeable, organic, carbonate, Fe/Mn oxides and residual fraction, respectively, were determined. Results showed that the highest activity concentrations for the studied radionuclides were on the bottom of the waste pile. In non-contaminated locations, about 80% of all radionuclides were in the residual fraction. Considering activity concentrations in the UMT, (238)U and (234)U are the most mobile. Mobility of (226)Ra is suppressed by high sulphate concentrations and is similar to mobility of (230)Th.

  10. Assessment of the vertical distribution of natural radionuclides in a mineralized uranium area in south-west Spain.

    PubMed

    Blanco Rodríguez, P; Vera Tomé, F; Lozano, J C

    2014-01-01

    Low-level alpha spectrometry techniques using semiconductor detectors (PIPS) and liquid scintillation (LKB Quantulus 1220™) were used to determine the activity concentration of (238)U, (234)U, (230)Th, (226)Ra, (232)Th, and (210)Pb in soil samples. The soils were collected from an old disused uranium mine located in southwest Spain. The soils were sampled from areas with different levels of influence from the installation and hence had different levels of contamination. The vertical profiles of the soils (down to 40 cm depth) were studied in order to evaluate the vertical distribution of the natural radionuclides. To determine the origin of these natural radionuclides the Enrichment Factor was used. Also, study of the activity ratios between radionuclides belonging to the same radioactive series allowed us to assess the different types of behaviors of the radionuclides involved. The vertical profiles for the radionuclide members of the (238)U series were different at each sampling point, depending on the level of influence of the installation. However, the profiles of each point were similar for the long-lived radionuclides of the (238)U series ((238)U, (234)U, (230)Th, and (226)Ra). Moreover, a major imbalance was observed between (210)Pb and (226)Ra in the surface layer, due to (222)Rn exhalation and the subsequent surface deposition of (210)Pb. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. EVALUATING MONITORED NATURAL ATTENUATION FOR RADIONUCLIDE AND INORGANIC CONTAMINANTS IN GROUNDWATER

    EPA Science Inventory

    Monitored Natural Attenuation (MNA) for inorganic contaminants is dependent on naturally occurring processes in the subsurface that act without human intervention to reduce the mass, toxicity, mobility, volume or concentration of contaminants. EPA is developing a technical refer...

  12. EVALUATING MONITORED NATURAL ATTENUATION FOR RADIONUCLIDE AND INORGANIC CONTAMINANTS IN GROUNDWATER

    EPA Science Inventory

    Monitored Natural Attenuation (MNA) for inorganic contaminants is dependent on naturally occurring processes in the subsurface that act without human intervention to reduce the mass, toxicity, mobility, volume or concentration of contaminants. EPA is developing a technical refer...

  13. A century of oil and gas exploration in Albania: assessment of Naturally Occurring Radioactive Materials (NORMs).

    PubMed

    Xhixha, G; Baldoncini, M; Callegari, I; Colonna, T; Hasani, F; Mantovani, F; Shala, F; Strati, V; Xhixha Kaçeli, M

    2015-11-01

    The Naturally Occurring Radioactive Materials (NORMs) that are potentially generated from oil and gas extractions in Albania have been disposed of without regulations for many decades, and therefore, an extensive survey in one of the most productive regions (Vlora-Elbasan) was performed. A total of 52 gamma ray spectrometry measurements of soil, oil-sand, sludge, produced water and crude oil samples were performed. We discovered that relatively low activity concentrations of (226)Ra, (228)Ra, (228)Th and (40)K, with concentrations of 23±2Bq/kg, 23±2Bq/kg, 24±3Bq/kg and 549±12Bq/kg, respectively, came from the oil-sands produced by the hydrocarbon extraction of the molasses formations. The mineralogical characterizations and the (228)Ra/(40)K and (226)Ra/(40)K ratios of these Neogene deposits confirmed the predictions of the geological and geodynamic models of a dismantling of the Mesozoic source rocks. The average activity concentrations (±standard deviations) of the radium isotopes ((226)Ra and (228)Ra) and of the (228)Th and (40)K radionuclides in soil samples were 20±5Bq/kg, 25±10Bq/kg, 25±9Bq/kg and 326±83Bq/kg, respectively. Based on the measurements in this study, the future radiological assessments of other fields in the region should be strategically planned to focus on the oil-sands from the molasses sediments. Disequilibrium in the (228)Ra decay segment was not observed in the soil, sludge or oil-sand samples within the standard uncertainties. After a detailed radiological characterization of the four primary oil fields, we concluded that the outdoor absorbed dose rate never exceeded the worldwide population weighted average absorbed dose rate in outdoor air from terrestrial gamma radiation.

  14. Effect of leachability on environmental risk assessment for naturally occurring radioactive materials in petroleum oil fields.

    PubMed

    Rajaretnam, G; Spitz, H B

    2000-02-01

    Elevated concentrations of naturally occurring radioactive material (NORM), including 238U, 232Th, and their progeny found in underground geologic deposits, are often encountered during crude oil recovery. Radium, the predominant radionuclide brought to the surface with the crude oil and produced water, co-precipitates with barium in the form of complex compounds of sulfates, carbonates, and silicates found in sludge and scale. These NORM deposits are highly stable and very insoluble under ambient conditions at the earth's surface. However, the co-precipitated radium matrix is not thermodynamically stable at reducing conditions which may enable a fraction of the radium to eventually be released to the environment. Although the fate of radium in uranium mill tailings has been studied extensively, the leachability of radium from crude oil NORM deposits exposed to acid-rain and other aging processes is generally unknown. The leachability of radium from NORM contaminated soil collected at a contaminated oil field in eastern Kentucky was determined using extraction fluids having wide range of pH reflecting different extreme environmental conditions. The average 226Ra concentration in the samples of soil subjected to leachability testing was 32.56 Bq g(-1) +/- 0.34 Bq g(-1). The average leaching potential of 226Ra observed in these NORM contaminated soil samples was 1.3% +/- 0.46% and was independent of the extraction fluid. Risk assessment calculations using the family farm scenario show that the annual dose to a person living and working on this NORM contaminated soil is mainly due to external gamma exposure and radon inhalation. However, waterborne pathways make a non-negligible contribution to the dose for the actual resident families living on farmland with the type of residual NORM contamination due to crude oil recovery operations.

  15. Distribution of natural radionuclides in surface soils in the vicinity of abandoned uranium mines in Serbia.

    PubMed

    Momčilović, Milan; Kovačević, Jovan; Tanić, Milan; Dorđević, Milan; Bačić, Goran; Dragović, Snežana

    2013-02-01

    The activity concentrations of natural radionuclides in soils from the area affected by uranium mining at Stara Planina Mountain in Serbia were studied and compared with the results obtained from an area with no mining activities (background area). In the affected area, the activity concentrations ranged from 1.75 to 19.2 mg kg(-1) for uranium and from 1.57 to 26.9 mg kg(-1) for thorium which is several-fold higher than those in the background area. The Th/U, K/U, and K/Th activity ratios were also determined and compared with data from similar studies worldwide. External gamma dose rate in the air due to uranium, thorium, and potassium at 1 m above ground level in the area affected by uranium mining was found to be 91.3 nGy h(-1), i.e., about two-fold higher than that in background area. The results of this preliminary study indicate the importance of radiological evaluation of the area and implementation of remedial measures in order to prevent further dispersion of radionuclides in the environment.

  16. Natural radionuclide uptake by mosses in eastern Serbia in 2008-2013.

    PubMed

    Čučulović, Ana Č; Sabovljević, Marko; Čučulović, Rodoljub Č; Veselinović, Dragan

    2016-03-01

    The results of the study on natural radionuclide content in 102 samples of the moss species randomly collected in 2008- 2013 at 30 locations of eastern Serbia are presented in the paper. The activity concentration values of 238U, 226Ra, 232Th, 40K, and 7Be determined by gamma spectrometry were within the intervals: 238U (1.1-50) Bq kg(-1), 226Ra (1.1-41) Bq kg(-1), 232Th (1.4-28) Bq kg(-1), 40K (64-484) Bq kg(-1) and 7Be (88-227) Bq kg(-1), not standing out of the average data reported for this region. The distribution of the obtained data for 226Ra, 232Th, and 238U activity concentration in the analysed mosses has shown values up to 10 Bq kg(-1) with frequencies 47.1 %, 54.9 % and 48.0 %, respectively. The obtained activity concentration values of primordial 40K and cosmogenic radionuclide 7Be were up to 500 Bq kg(-1) and about 90 % of all the results for 7Be uptake by mosses were in the 200-250 Bq kg(-1) concentration range.

  17. Evaluation of occupational exposure to naturally occurring radioactive materials in the Iranian ceramics industry.

    PubMed

    Fathabadi, N; Farahani, M V; Amani, S; Moradi, M; Haddadi, B

    2011-06-01

    Zircon contains small amounts of uranium, thorium and radium in its crystalline structure. The ceramic industry is one of the major consumers of zirconium compounds that are used as an ingredient at ∼10-20 % by weight in glaze. In this study, seven different ceramic factories have been investigated regarding the presence of radioactive elements with focus on natural radioactivity. The overall objective of this investigation is to provide information regarding the radiation exposure to workers in the ceramic industry due to naturally occurring radioactive materials. This objective is met by collecting existing radiological data specific to glaze production and generating new data from sampling activities. The sampling effort involves the whole process of glaze production. External exposures are monitored using a portable gamma-ray spectrometer and environmental thermoluminescence dosimeters, by placing them for 6 months in some workplaces. Internal routes of exposure (mainly inhalation) are studied using air sampling, and gross alpha and beta counting. Measurement of radon gas and its progeny is performed by continuous radon gas monitors that use pulse ionisation chambers. Natural radioactivity due to the presence of ²³⁸U, ²³²Th and ⁴⁰K in zirconium compounds, glazes and other samples is measured by a gamma-ray spectrometry system with a high-purity germanium detector. The average concentrations of ²³⁸U and ²³²Th observed in the zirconium compounds are >3300 and >550 Bq kg⁻¹, respectively. The specific activities of other samples are much lower than in zirconium compounds. The annual effective dose from external radiation had a mean value of ∼0.13 mSv y⁻¹. Dust sampling revealed the greatest values in the process at the powdering site and hand weighing places. In these plants, the annual average effective dose from inhalation of long-lived airborne radionuclides was 0.226 mSv. ²²²Rn gas concentrations in the glaze production plant and

  18. Different sources of suspended sediment according to particle size determined by natural radionuclides

    NASA Astrophysics Data System (ADS)

    Mizugaki, S.; Ohtsuka, J.; Maruyama, M.; Hamamoto, S.; Murakami, Y.

    2012-12-01

    Extensive human activity and climate change have given great impacts on the sediment balance and connectivity between fluvial and coastal systems, causing sediment-related problems such as sedimentation in reservoir, coastal erosion and water pollution by prolonged turbid water. The dynamics of suspended sediment is one of the most important issues in watershed and coastal management. Suspended sediment load transported to ocean by a river commonly represents a mixture of sediments delivered from different locations and source types within the contributing catchment. In our previous study, we have found that the three natural radionuclides are available to discriminate the source areas of suspended sediment represented by six different bed rock type (sedimentary rock, accretionary sedimentary rock, accretionary basalt block, accretionary volcanic rock, plutonic rock and metamorphic rock), and that the contribution of each source areas to suspended sediment can be estimated (Mizugaki et al., 2012). To elucidate the sources of suspended sediment from mountain to coastal area, the fingerprinting was conducted using natural radionuclide tracers across a couple of adjacent watersheds, the Saru River and Mu River watersheds in central Hokkaido, northern Japan. We collected suspended sediments at outlets of the 13 sub-catchments (0.7-27.2 km2) and 12 stream channels with mid- to large-scaled watershed areas (17-1,333 km2), deposited sediments across a dam reservoir and coastal sediments, in total 389 samples. For collected sediment samples, grain size distributions were measured by laser-diffraction particle size analyzer. The specific surface areas of the samples were estimated using their grain size distribution and the spherical approximation of the particles in each class. For fingerprint the source of suspended sediment, three natural radionuclide activities, 212Pb, 228Ac and 40K, were measured by gamma-ray spectrometry. Specific surface area of the sediment showed

  19. Comparison of concentrations of natural and artifical radionuclides in Plankton from French Polynesian and Australian coastal waters

    SciTech Connect

    Poletiko, C.; Twining, J.R.; Jeffree, R.A.

    1994-12-31

    Zooplankton samples from French Polynesian and Australian coastal waters were analysed for natural and artificial radionuclides. Quality control was assured by correlating replicate analyses between three laboratories and by intercomparison exercise. Pu-2.39/240 was detected sporadically among samples from both regions, with the highest levels being more consistently found in Tuamotu-Gambier samples. The artificial radionuclides Cs-137, Cs-134, Sr-90 and Co-60 were not detected. Of the natural nuclides, Ac-228 was detected in shallow continental waters off Northern Australia and an inverse relationship (P< 0.02) was established between plankton density and their Po-210 concentration.

  20. Natural radionuclide and radiological assessment of building materials in high background radiation areas of Ramsar, Iran

    PubMed Central

    Bavarnegin, Elham; Moghaddam, Masoud Vahabi; Fathabadi, Nasrin

    2013-01-01

    Building materials, collected from different sites in Ramsar, a northern coastal city in Iran, were analyzed for their natural radionuclide contents. The measurements were carried out using a high resolution high purity Germanium (HPGe) gamma-ray spectrometer system. The activity concentration of 226Ra, 232Th, and 40K content varied from below the minimum detection limit up to 86,400 Bqkg-1, 187 Bqkg-1, and 1350 Bqkg-1, respectively. The radiological hazards incurred from the use of these building materials were estimated through various radiation hazard indices. The result of this survey shows that values obtained for some samples are more than the internationally accepted maximum limits and as such, the use of them as a building material pose significant radiation hazard to individuals. PMID:23776313

  1. Natural radionuclide and radiological assessment of building materials in high background radiation areas of Ramsar, Iran.

    PubMed

    Bavarnegin, Elham; Moghaddam, Masoud Vahabi; Fathabadi, Nasrin

    2013-04-01

    Building materials, collected from different sites in Ramsar, a northern coastal city in Iran, were analyzed for their natural radionuclide contents. The measurements were carried out using a high resolution high purity Germanium (HPGe) gamma-ray spectrometer system. The activity concentration of (226)Ra, (232)Th, and (40)K content varied from below the minimum detection limit up to 86,400 Bqkg(-1), 187 Bqkg(-1), and 1350 Bqkg(-1), respectively. The radiological hazards incurred from the use of these building materials were estimated through various radiation hazard indices. The result of this survey shows that values obtained for some samples are more than the internationally accepted maximum limits and as such, the use of them as a building material pose significant radiation hazard to individuals.

  2. Measurement of natural radionuclides in Malaysian bottled mineral water and consequent health risk estimation

    SciTech Connect

    Priharti, W.; Samat, S. B.; Yasir, M. S.

    2015-09-25

    The radionuclides of {sup 226}Ra, {sup 232}Th and {sup 40}K were measured in ten mineral water samples, of which from the radioactivity obtained, the ingestion doses for infants, children and adults were calculated and the cancer risk for the adult was estimated. Results showed that the calculated ingestion doses for the three age categories are much lower than the average worldwide ingestion exposure of 0.29 mSv/y and the estimated cancer risk is much lower than the cancer risk of 8.40 × 10{sup −3} (estimated from the total natural radiation dose of 2.40 mSv/y). The present study concludes that the bottled mineral water produced in Malaysia is safe for daily human consumption.

  3. Measurement of natural radionuclides in Malaysian bottled mineral water and consequent health risk estimation

    NASA Astrophysics Data System (ADS)

    Priharti, W.; Samat, S. B.; Yasir, M. S.

    2015-09-01

    The radionuclides of 226Ra, 232Th and 40K were measured in ten mineral water samples, of which from the radioactivity obtained, the ingestion doses for infants, children and adults were calculated and the cancer risk for the adult was estimated. Results showed that the calculated ingestion doses for the three age categories are much lower than the average worldwide ingestion exposure of 0.29 mSv/y and the estimated cancer risk is much lower than the cancer risk of 8.40 × 10-3 (estimated from the total natural radiation dose of 2.40 mSv/y). The present study concludes that the bottled mineral water produced in Malaysia is safe for daily human consumption.

  4. A national survey of natural radionuclides in soils and terrestrial radiation exposure in Iran.

    PubMed

    Kardan, M R; Fathabdi, N; Attarilar, A; Esmaeili-Gheshlaghi, M T; Karimi, M; Najafi, A; Hosseini, S S

    2017-08-24

    In the past, some efforts have been made for measuring natural radioactivity and evaluating public exposure to natural radiation in certain areas of Iran especially in well-known High Level Natural Radiation Areas (HLNRA) in Ramsar and Mahallat. However, the information on radionuclide concentrations, and, consequently, terrestrial radiation exposure for many other areas are not available. There was therefore a need for a systematic and nation-wide survey. For this purpose, 979 soil samples from 31 provinces were collected. The activity concentrations of (40)K, (226)Ra and (232)Th were measured by HPGe detector. The average activity concentrations for Iran were found to be 457.7 Bq/kg for (40)K, 24.3 Bq/kg for (226)Ra and 25.8 Bq/kg for (232)Th. Results were compared with previous regional or provincial surveys. The population-weighted average outdoor and indoor annual effective dose due to external exposure to terrestrial sources of radiation are 0.06 mSv and 0.33 mSv, respectively. It was shown that there is a significant correlation between the activity concentrations of (232)Th and (40)K in soil. In addition, the results of chi square tests show normal and lognormal distributions cannot be considered for the frequency distributions of activity concentration of (232)Th and (226) Ra while (40)K has a normal distribution. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Correlation analysis of the natural radionuclides in soil and indoor radon in Vojvodina, Province of Serbia.

    PubMed

    Forkapic, S; Maletić, D; Vasin, J; Bikit, K; Mrdja, D; Bikit, I; Udovičić, V; Banjanac, R

    2017-01-01

    The most dominant source of indoor radon is the underlying soil, so the enhanced levels of radon are usually expected in mountain regions and geology units with high radium and uranium content in surface soils. Laboratory for radioactivity and dose measurement, Faculty of Sciences, University of Novi Sad has rich databases of natural radionuclides concentrations in Vojvodina soil and also of indoor radon concentrations for the region of Vojvodina, Northern Province of Serbia. In this paper we present the results of correlative and multivariate analysis of these results and soil characteristics in order to estimate the geogenic radon potential. The correlative and multivariate analysis were done using Toolkit for Multivariate Analysis software package TMVA package, within ROOT analysis framework, which uses several comparable multivariate methods for our analysis. The evaluation ranking results based on the best signal efficiency and purity, show that the Boosted Decision Trees (BDT) and Multi Layer Preceptor (MLP), based on Artificial Neural Network (ANN), are multivariate methods which give the best results in the analysis. The BDTG multivariate method shows that variables with the highest importance are radio-nuclides activity on 30 cm depth. Moreover, the multivariate regression methods give a good approximation of indoor radon activity using full set of input variables. On several locations in the city of Novi Sad the results of indoor radon concentrations, radon emanation from soil, gamma spectrometry measurements of underlying soil and geology characteristics of soil were analyzed in detail in order to verify previously obtained correlations for Vojvodina soil. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Naturally occurring radioactive material from the aluminium industry--a case study: the Egyptian Aluminium Company, Nag Hammady, Egypt.

    PubMed

    Abbady, Adel G E; El-Arabi, A M

    2006-12-01

    The activity concentrations and the gamma-absorbed dose rates of the terrestrial naturally occurring radionuclides (226)Ra and (232)Th were determined in samples of bauxite, alumina and aluminium dross tailings industrial waste (used to produce two types of alums) using high purity germanium (HPGe) gamma ray spectrometry. The bauxite and alumina are imported by Egyptalum (The Egyptian Aluminium Company, Nag Hammady, Egypt) from Guinea and India. The activity concentrations in the bauxite range from 29 +/- 1 to 112 +/- 6 Bq kg(-1) for (226)Ra, and 151 +/- 8 to 525 +/- 12 Bq kg(-1) for (232)Th, with mean values of 62 +/- 8 and 378 +/- 50 Bq kg(-1), respectively. With respect to alumina and tail, the mean values are 5.7 +/- 1.1 and 8.4 +/- 0.8 Bq kg(-1) for (226)Ra and 7.2 +/- 1.6 and 10.7 +/- 1.2 Bq kg(-1) for (232)Th. Potassium-40 was not detected in any of the studied samples. The measured activity concentrations of (226)Ra and (232)Th in bauxite are higher than the world average while in alumina and tail they are lower. As a measure of radiation hazard to the occupational workers and members of the public, the Ra equivalent activities and external gamma dose rates due to natural radionuclides at 1 m above the ground surface were calculated. The external gamma-radiation doses received by the Egyptalum workers are 97, 409, 8.5 and 12.7 microSv y(-1) for the Guinean and Indian bauxite, the alumina and tail, respectively, which is well below the recommended allowed dose of 1 mSv y(-1) for non-exposed workers.

  7. Long-Term Toxicity of Naturally Occurring Asbestos in Male Fischer 344 Rats

    EPA Science Inventory

    Naturally occurring asbestos (NOA) fibers are found in geologic deposits that may be disturbed by mining, earthworks, or natural processes, resulting in adverse health risks to exposed individuals. The toxicities of Libby amphibole and NOA samples including Sumas Mountain chrysot...

  8. Long-Term Toxicity of Naturally Occurring Asbestos in Male Fischer 344 Rats

    EPA Science Inventory

    Naturally occurring asbestos (NOA) fibers are found in geologic deposits that may be disturbed by mining, earthworks, or natural processes, resulting in adverse health risks to exposed individuals. The toxicities of Libby amphibole and NOA samples including Sumas Mountain chrysot...

  9. Natural radionuclides in ceramic building materials available in Cuddalore district, Tamil Nadu, India.

    PubMed

    Rajamannan, B; Viruthagiri, G; Suresh Jawahar, K

    2013-10-01

    The activity concentrations of radium, thorium and potassium can vary from material to material and they should be measured as the radiation is hazardous for human health. Thus, studies have been planned to obtain the radioactivity of ceramic building materials used in Cuddalore District, Tamilnadu, India. The radioactivity of some ceramic materials used in this region has been measured using a gamma-ray spectrometry, which contains an NaI(Tl) detector connected to multichannel analyzer. The specific activities of (226)Ra, (232)Th and (40)K, from the selected ceramic building materials, were in the range of 9.89-30.75, 24.68-70.4, 117.19-415.83 Bq kg(-1), respectively. The radium equivalent activity, absorbed gamma dose rate (D) and annual effective dose rate associated with the natural radionuclides are calculated to assess the radiation hazards of the natural radioactivity in the ceramic building materials. It was found that none of the results exceeds the recommended limit value.

  10. Radiation dose to Malaysian infants from natural radionuclides via consumption of powdered milk

    SciTech Connect

    Uwatse, Onosohwo Bemigho; Olatunji, Michael Adekunle; Khandaker, Mayeen Uddin; Amin, Yusoff Mohd.

    2015-04-24

    Milk is the basic food stuff for the infants because they generally consume more milk on a daily basis as its minerals and proteins are essential for their growth and development, therefore, it is very important to assess the natural radioactivity levels and the associated dose in the widely consumed powered infant’s milk. As a result, 14 brands of infant’s powdered milk were collected from different supermarkets around Selangor, Malaysia and analysed for {sup 226}Ra, {sup 232}Th and {sup 40}K activities. The obtained mean activity of {sup 226}Ra, {sup 232}Th and {sup 40}K are 3.05±1.84, 2.55±2.48 and 99.1±69.5 Bqkg{sup −1}, respectively. Among the analysed milk samples, the brand from Philippines (Lactogen) showed low level of radioactivity while Singaporean brand (S26 SMA Gold) showed the highest. The estimated mean annual effective doses due to the ingestion of natural radionuclides in the sampled milk are 635 and 111 µSv for infant ≤ 1y and infant 1-2y, respectively. The obtained dose value does not yet pose any significant radiological hazards to the population under investigation comparing with the 1.0 mSvy{sup −1} recommended by ICRP for all ages.

  11. Utilization of natural hematite as reactive barrier for immobilization of radionuclides from radioactive liquid waste.

    PubMed

    El Afifi, E M; Attallah, M F; Borai, E H

    2016-01-01

    Potential utilization of hematite as a natural material for immobilization of long-lived radionuclides from radioactive liquid waste was investigated. Hematite ore has been characterized by different analytical tools such as Fourier transformer infrared (FTIR), X-ray fluorescence (XRF), powder X-ray diffraction (XRD), thermogravimetry (TG) and differential thermal (DT) analysis, scanning electron microscopy (SEM) and BET-surface area. In this study, europium was used as REEs(III) and as a homolog of Am(III)-isotopes (such as (241)Am of 432.6 y, (242m)Am of 141 y and (243)Am of 7370 y). Micro particles of the hematite ore were used for treatment of radioactive waste containing (152+154)Eu(III). The results indicated that 96% (4.1 × 10(4) Bq) of (152+154)Eu(III) was efficiently retained onto hematite ore. Kinetic experiments indicated that the processes could be simulated by a pseudo-second-order model and suggested that the process may be chemisorption in nature. The applicability of Langmuir, Freundlich and Temkin models was investigated. It was found that Langmuir isotherm exhibited the best fit with the experimental results. It can be concluded that hematite is an economic and efficient reactive barrier for immobilization of long-lived radio isotopes of actinides and REEs(III). Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Radiation dose to Malaysian infants from natural radionuclides via consumption of powdered milk

    NASA Astrophysics Data System (ADS)

    Uwatse, Onosohwo Bemigho; Olatunji, Michael Adekunle; Khandaker, Mayeen Uddin; Amin, Yusoff Mohd.

    2015-04-01

    Milk is the basic food stuff for the infants because they generally consume more milk on a daily basis as its minerals and proteins are essential for their growth and development, therefore, it is very important to assess the natural radioactivity levels and the associated dose in the widely consumed powered infant's milk. As a result, 14 brands of infant's powdered milk were collected from different supermarkets around Selangor, Malaysia and analysed for 226Ra, 232Th and 40K activities. The obtained mean activity of 226Ra, 232Th and 40K are 3.05±1.84, 2.55±2.48 and 99.1±69.5 Bqkg-1, respectively. Among the analysed milk samples, the brand from Philippines (Lactogen) showed low level of radioactivity while Singaporean brand (S26 SMA Gold) showed the highest. The estimated mean annual effective doses due to the ingestion of natural radionuclides in the sampled milk are 635 and 111 µSv for infant ≤ 1y and infant 1-2y, respectively. The obtained dose value does not yet pose any significant radiological hazards to the population under investigation comparing with the 1.0 mSvy-1 recommended by ICRP for all ages.

  13. Polyion complex libraries possessing naturally occurring differentiation for pattern-based protein discrimination.

    PubMed

    Tomita, Shunsuke; Yoshimoto, Keitaro

    2013-11-14

    Polyion complexes with naturally occurring differentiation of enzymes serve to create receptor libraries with high differentiability and lower synthetic demands for pattern-based protein discrimination.

  14. Suspended sediment from different geological sources in a watershed determined by natural radionuclides

    NASA Astrophysics Data System (ADS)

    Mizugaki, S.; Abe, T.; Murakami, Y.; Kubo, M.; Maruyama, M.; Hamamoto, S.

    2011-12-01

    The geological setting is essential for occurrence of slope failure and landslide so that the geology may control the suspended sediment yield with different magnitude. In the Saru River watershed of central Hokkaido, northern Japan, the typhoon Etau in August 2003 brought heavy rainfall, causing the slope failure and landslide across the areas of various geologies and the highest sediment yield since 1960s. Prolonged sediment runoff has caused the serious problems in association with turbid water, sedimentation in the reservoir, and their impacts on fishery and ecology downstream. To clarify the suspended sediment sources within the Nukabira River watershed, a tributary of Saru River, hydrological monitoring of discharge and turbidity and fingerprinting technique using natural radionuclide were conducted during a heavy rainfall event in August 2010. GIS analysis for slope failure and landslide areas was also conducted to investigate the distribution of potential suspended sediment sources. The activity of radionuclides, including U-series, Th-series, cesium-137 and potassium-40 were determined by gamma ray spectrometry. Statistical analysis showed the best composite fingerprints of Pb-212, Ac-228 and K-40 to classify the suspended sediment sources into six geological units, which were sedimentary rock, plutonic rock, metamorphic rock and three types of cretaceous accretionary complex consist of sedimentary rock, basalt block and volcanic rock. The contribution of source group to suspended sediment was calculated according to the assumption that the Mahalanobis distance in tracer properties between sources and suspended sediment can represent relative contribution of the source. During the rainfall event on August 11, 2011, dominant source of suspended sediment was found to be the areas consist of metamorphic rock (31%), sedimentary rock (30%) and accretionary sedimentary rock (24%). GIS analysis showed the spatial distribution of slope failure and landslide within

  15. Segregation of naturally occurring mitochondrial DNA variants in a mini-pig model

    USDA-ARS?s Scientific Manuscript database

    Within cells and tissues, the maternally inherited mitochondrial genome (mtDNA) is present in multimeric form and can harbour naturally occurring variants. Whilst high variant load can cause mitochondrial disease, naturally occurring mtDNA variants likely persist at low levels across generations of ...

  16. Gamma-ray methods for determining natural and anthropogenic radionuclides in environmental and soil science

    SciTech Connect

    Harbottle, G.; Evans, C.V.

    1997-05-01

    Gamma-ray methods for the determination of radionuclides in environmental materials are convenient because they generally require less bench-top preparation time than, for example, determinations based on alpha-particle pulse-height analysis. Also, parallel measurements of chemical yield are not needed, and typically several radionuclides can be determined simultaneously. In this paper, the authors review gamma-ray methods currently in use at Brookhaven, and present a new method for the determination of the radionuclide protactinium-231 in soils and other environmental materials, using the gamma-ray deconvolution package in the EG&G Ortec {open_quotes}Gammavision{close_quotes} software.

  17. A study of radionuclides, metals and stable lead isotope ratios in sediments and soils in the vicinity of natural U-mineralisation areas in the Northern Territory.

    PubMed

    Frostick, A; Bollhöfer, A; Parry, D

    2011-10-01

    Australian guidelines recommend that tailings materials from uranium (U) mining and milling be contained without any detrimental impact on the environment for at least 1000 years. Natural analogue sites are being investigated to determine if they can provide data on the rates of natural erosion processes which occur over these timescales, for input into predictive geomorphic computer models. This paper presents radionuclide, metal and stable lead (Pb) isotope data from sediment cores and surface soils in the vicinity of two mineralised areas in the Alligator Rivers Region. Surface scrapes from the natural Anomaly #2, south of the Ranger mineral lease, exhibit radiogenic (206)Pb/(207)Pb and (208)Pb/(207)Pb ratios, and elevated U and metal concentrations typical for a near surface U anomaly. In contrast, samples taken from the Koongarra mineral lease (KML) show radionuclide activity and metal concentrations similar to natural areas elsewhere in the Alligator Rivers Region and Pb isotope ratios are closer to present day average crustal ratios (PDAC), as the orebodies at KML are covered by surficial sand. A sediment core collected from Anbangbang Billabong, downstream of KML, exhibits small variations in Pb isotope ratios that indicate that approximately 1% of the upper sediments in the sediment core may be derived from material originating from the U anomaly at Koongarra.

  18. Natural Radionuclides In Mineral Sand Products From A Processing Plant In Northeastern Brazil

    SciTech Connect

    Hazin, C. A.; Khoury, H. J.; Silveira, S. V.

    2008-08-07

    This paper presents the results of a preliminary investigation carried out in a mineral sand processing plant located in the coastal region of Northeastern Brazil. The study aimed to determine the natural radionuclide content of the mineral products extracted from beach sands, with special emphasis on zircon. Measurements were performed through gamma spectrometry, by using a high-purity germanium detector (HPGe) coupled to a multichannel analyzer. Activity concentrations of {sup 226}Ra and {sup 228}Ra were determined by measuring some of the radon progeny activity concentrations ({sup 214}Pb and {sup 214}Bi for {sup 226}Ra, and {sup 228}Ac and {sup 208}Tl for {sup 228}Ra) and assuming an equilibrium condition upstream of the radon progeny. The results of the measurements carried out for the zircon samples showed activity concentrations ranging from 18.09 to 48.51 kBq kg{sup -1} for {sup 226}Ra. The results for {sup 228}Ra, on the other hand, were consistently lower than those obtained for {sup 226}Ra, ranging from 2.72 to 18.31 kBq kg{sup -1}.

  19. Distribution of natural radionuclides in soils and beach sands of Abana-Çatalzeytin (Kastamonu)

    SciTech Connect

    Kurnaz, Aslı Özcan, Murat Çetiner, M. Atıf

    2016-03-25

    A gamma spectrometric study of distribution of natural radionuclides in soil and beach sand samples collected from the terrestrial and coastal environment of Abana and Çatalzeytin counties of Kastamonu Province in Turkey was performed with the aim of estimating the radiation hazard of the tourist area and the concentrations of {sup 238}U, {sup 232}Th and {sup 40}K were determined. The activity concentrations of {sup 238}U, {sup 232}Th and {sup 40}K were determined in the ranges 14.95–56.0, 46.5–99.4 and 357.5–871.3 Bqkg{sup −1} for soil samples and the mean concentrations were ascertained as 42.34, 71.24 and 624.18 Bqkg{sup −1}, respectively. In sand samples, {sup 238}U, {sup 232}Th and {sup 40}K contents were varied in the ranges of 13.35-41.6, 30.9-53.4 and 275.5-601.3 Bqkg{sup −1} and the mean concentrations were ascertained as 20.57, 45.05 and 411.71 Bqkg{sup −1}, respectively. The mean annual effective doses were calculated as 113.08 and 69.16 µSvy{sup −1} for the soil and sand samples, respectively.

  20. Recent advances in the detection of specific natural organic compounds as carriers for radionuclides in soil and water environments, with examples of radioiodine and plutonium.

    PubMed

    Santschi, P H; Xu, C; Zhang, S; Schwehr, K A; Lin, P; Yeager, C M; Kaplan, D I

    2017-03-09

    Among the key environmental factors influencing the fate and transport of radionuclides in the environment is natural organic matter (NOM). While this has been known for decades, there still remains great uncertainty in predicting NOM-radionuclide interactions because of lack of understanding of radionuclide interactions with the specific organic moieties within NOM. Furthermore, radionuclide-NOM studies conducted using modelled organic compounds or elevated radionuclide concentrations provide compromised information related to true environmental conditions. Thus, sensitive techniques are required not only for the detection of radionuclides, and their different species, at ambient and/or far-field concentrations, but also for potential trace organic compounds that are chemically binding these radionuclides. GC-MS and AMS techniques developed in our lab are reviewed here that aim to assess how two radionuclides, iodine and plutonium, form strong bonds with NOM by entirely different mechanisms; iodine tends to bind to aromatic functionalities, whereas plutonium binds to N-containing hydroxamate siderophores at ambient concentrations. While low-level measurements are a prerequisite for assessing iodine and plutonium migration at nuclear waste sites and as environmental tracers, it is necessary to determine their in-situ speciation, which ultimately controls their mobility and transport in natural environments. More importantly, advanced molecular-level instrumentation (e.g., nuclear magnetic resonance (NMR) and Fourier-transform ion cyclotron resonance coupled with electrospray ionization (ESI-FTICRMS) were applied to resolve either directly or indirectly the molecular environments in which the radionuclides are associated with the NOM.

  1. Technologically Enhanced Naturally Occurring Radioactive Materials (TENORM) in the Oil and Gas Industry: A Review.

    PubMed

    Doyi, Israel; Essumang, David Kofi; Dampare, Samuel; Glover, Eric Tetteh

    Radiation is part of the natural environment: it is estimated that approximately 80 % of all human exposure comes from naturally occurring or background radiation. Certain extractive industries such as mining and oil logging have the potential to increase the risk of radiation exposure to the environment and humans by concentrating the quantities of naturally occurring radiation beyond normal background levels (Azeri-Chirag-Gunashli 2004).

  2. Transfer of natural and anthropogenic radionuclides to ants, bryophytes and lichen in a semi-natural ecosystem.

    PubMed

    Dragović, Snezana; Howard, Brenda J; Caborn, Jane A; Barnett, Catherine L; Mihailović, Nevena

    2010-07-01

    Few data are available to quantify the transfer of both natural and anthropogenic radionuclides to detritivorous invertebrates to facilitate estimation of the internal dose to such biota in models used to assess radiation exposure. To enhance the available data, activity concentrations of (137)Cs, (40)K, (90)Sr, (239 + 240)Pu, (241)Am, (235)U and (238)U were measured in ants (Formicidae) and corresponding undisturbed soil collected from the Zlatibor mountain in Serbia and ant/soil concentration ratios (CR) calculated. The (241)Am concentration ratios for ants were fourfold higher than those calculated for ants in a previous study whereas they are similar to the more numerous data previously reported for a range of detritivorous invertebrates in other studies. CR values for (137)Cs in ants were similar to the few other reported values and slightly lower than those for a range of detritivorous invertebrates. Those for (239 + 240)Pu were slightly higher than those for ants in two other studies but they were close to upper limit of a range of data reported for detritivorous invertebrates. All the CR values will be included in a future revision of the ERICA Tool database and will particularly improve the information available for uranium.

  3. Distribution and environmental impacts of metals and natural radionuclides in marine sediments in-front of different wadies mouth along the Egyptian Red Sea Coast.

    PubMed

    el-Taher, A; Madkour, H A

    2011-02-01

    Forty-four marine sediment samples were collected in-front of wadis mouth along the Egyptian Red Sea coast: Wadi El-Hamra, Wadi El-Esh, Wadi Abu-Shaar, Wadi El-Gemal and Wadi Khashir (Hamata). Several investigations of natural activity and trace metals of surface sediments were carried out. Distributions of naturally occurring radioactive materials (NORM) of (226)Ra, (232)Th and (40)K in the marine sediments were determined using NaI (Tl) γ-ray spectrometry. The average activities (range) of natural radionuclides in all wadis in the studied areas are 27.38 (18-48) Bq kg(-1) for (226)Ra, 38.45 (34-110) Bq kg(-1) for (232)Th and 419.4 (214-641) Bq kg(-1) for (40)K. These results are in agreement with earlier reported data. A comparison of radionuclide activities in the sediment of the studied areas and in other coastal and aquatic environments is given. The radiation hazard parameters (absorbed dose rate, radium equivalent activity and external hazard index) are calculated and compared with the reported data. The results of measurements will serve as base line data and background reference level for Egyptian coastlines. Copyright © 2010 Elsevier Ltd. All rights reserved.

  4. Effectiveness of mineral soil to adsorb the natural occurring radioactive material (norm), uranium and thorium

    SciTech Connect

    Amir, Muhammad Nur Iman; Ismail, Nurul Izzatiafifi; Wood, Ab. Khalik Saat, Ahmad; Hamzah, Zaini

    2015-04-29

    A study has been performed on U-soil and Th-soil adsorption of three types of soil collected from Selangor State of Malaysia which are Saujana Putra, Bukit Changgang and Jenderam Hilir. In this study, natural radionuclide (U and Th) soil adsorption based on batch experiments with various initial concentrations of the radionuclide elements were carried out. Parameters that were set constant include pH at 5;amount of soil used was 5 g each, contact time was 24 hour and different initial concentration for each solution of U and Th which is 5 mg/L, 10 mg/L, 15 mg/L, 20 mg/L, 25 mg/L and 40 mg/L were used. The K{sub d} values for each type of soil were determined in this batch experiments which was based on US-EPA method, in order to estimate adsorption capacity of the soil.The K{sub d} values of Th found higher than Kd values of U for all of the soil samples, and the highest was found on the soil collected from Bukit Changgang. The soil clay content was one of factors to influence the adsorption of both U and Th from dilute initial solution. The U-soil and Th-soil adsorption process for all the soil samples studied are generally obeying unimolecular layer Langmuir isotherm model. From Langmuir isotherm, the maximum adsorption capacity for U was 0.393mg/g and for Th was 1.53 mg/g for the soil that was taken from Bukit Changgang. From the study, it suggested that the soil from Bukit Changgang applicable as potential enhanced barrier for site disposing waste containing U and Th.

  5. Effectiveness of mineral soil to adsorb the natural occurring radioactive material (norm), uranium and thorium

    NASA Astrophysics Data System (ADS)

    Amir, Muhammad Nur Iman; Ismail, Nurul Izzatiafifi; Wood, Ab. Khalik; Saat, Ahmad; Hamzah, Zaini

    2015-04-01

    A study has been performed on U-soil and Th-soil adsorption of three types of soil collected from Selangor State of Malaysia which are Saujana Putra, Bukit Changgang and Jenderam Hilir. In this study, natural radionuclide (U and Th) soil adsorption based on batch experiments with various initial concentrations of the radionuclide elements were carried out. Parameters that were set constant include pH at 5;amount of soil used was 5 g each, contact time was 24 hour and different initial concentration for each solution of U and Th which is 5 mg/L, 10 mg/L, 15 mg/L, 20 mg/L, 25 mg/L and 40 mg/L were used. The Kd values for each type of soil were determined in this batch experiments which was based on US-EPA method, in order to estimate adsorption capacity of the soil.The Kd values of Th found higher than Kd values of U for all of the soil samples, and the highest was found on the soil collected from Bukit Changgang. The soil clay content was one of factors to influence the adsorption of both U and Th from dilute initial solution. The U-soil and Th-soil adsorption process for all the soil samples studied are generally obeying unimolecular layer Langmuir isotherm model. From Langmuir isotherm, the maximum adsorption capacity for U was 0.393mg/g and for Th was 1.53 mg/g for the soil that was taken from Bukit Changgang. From the study, it suggested that the soil from Bukit Changgang applicable as potential enhanced barrier for site disposing waste containing U and Th.

  6. Computation Of The Residual Radionuclide Activity Within Three Natural Waterways At The Savannah River Site

    SciTech Connect

    Hiergesell, R. A.; Phifer, M. A.

    2014-01-07

    In 2010 a Composite Analysis (CA) of the U.S. Department of Energy’s (DOE’s) Savannah River Site (SRS) was completed. This investigation evaluated the dose impact of the anticipated SRS End State residual sources of radionuclides to offsite members of the public. Doses were assessed at the locations where SRS site streams discharge into the Savannah River at the perimeter of the SRS. Although the model developed to perform this computation indicated that the dose constraint of 0.3 mSv/yr (30 mrem/yr), associated with CA, was not approached at the Points of Assessment (POAs), a significant contribution to the total computed dose was derived from the radionuclides (primarily Cs-137) bound-up in the soil and sediment of the drainage corridors of several SRS streams. DOE’s Low Level Waste Federal Review Group (LFRG) reviewed the 2010 CA and identified several items to be addressed in the SRS Maintenance Program. One of the items recognized Cs-137 in the Lower Three Runs (LTR) Integrator Operable Unit (IOU), as a significant CA dose driver. The item made the recommendation that SRS update the estimated radionuclide inventory, including Cs-137, in the LTR IOU. That initial work has been completed and its radionuclide inventory refined. There are five additional streams at SRS and the next phase of the response to the LFRG concern was to obtain a more accurate inventory and distribution of radionuclides in three of those streams, Fourmile Branch (FMB), Pen Branch (PB) and Steel Creek (SC). Each of these streams is designated as an IOU, which are defined for the purpose of this investigation as the surface water bodies and associated wetlands, including the channel sediment, floodplain sed/soil, and related biota. If present, radionuclides associated with IOUs are adsorbed to the streambed sediment and soils of the shallow floodplains that lie immediately adjacent to stream channels. The scope of this effort included the evaluation of any previous sampling and

  7. APPLICATION OF THE NATURALLY-OCCURRING DEUTERIUM ISOTOPE TO TRACING THE CAPILLARY FRINGE

    EPA Science Inventory

    Naturally-occurring deuterium is a useful tracer of subsurface hydrologic processes. A possible application includes the identification of capillary fringes in the vadose zone. Multiple and discontinuous water tables persist in many temperate regions, under various hydrogeologi...

  8. APPLICATION OF THE NATURALLY-OCCURRING DEUTERIUM ISOTOPE TO TRACING THE CAPILLARY FRINGE

    EPA Science Inventory

    Naturally-occurring deuterium is a useful tracer of subsurface hydrologic processes. A possible application includes the identification of capillary fringes in the vadose zone. Multiple and discontinuous water tables persist in many temperate regions, under various hydrogeologi...

  9. DECIPHERING NATURALLY-OCCURRING PB CONTAMINATION IMPACTING DRINKING WATER WELLS: SHAKER VILLAGE CATCHMENT, MAINE.

    EPA Science Inventory

    Trace Pb concentrations in groundwater within glacial deposits across Maine fluctuate considerably. Deciphering the distribution and sources of naturally occurring Pb in groundwater with only the use of conventional anomaly identification techniques presents a challenge. In a rep...

  10. Examination of naturally occurring polyacetylenes and alpha-terthienyl for their ability to induce cytogenetic damage.

    PubMed

    MacRae, W D; Chan, G F; Wat, C K; Towers, G H; Lam, J

    1980-09-15

    alpha-Terthienyl and 5 polyacetylenes were examined for chromosome damaging activity using Syrian hamster cells. None of these naturally occurring compounds induced sister chromatid exchanges and neither alpha-terthienyl nor phenylheptatriyne induced chromosome aberrations.

  11. Radiological Impact Associated to Technologically Enhanced Naturally Occurring Radioactive Materials (TENORM) from Coal-Fired Power Plants Emissions - 13436

    SciTech Connect

    Dinis, Maria de Lurdes; Fiuza, Antonio; Soeiro de Carvalho, Jose; Gois, Joaquim; Meira Castro, Ana Cristina

    2013-07-01

    Certain materials used and produced in a wide range of non-nuclear industries contain enhanced activity concentrations of natural radionuclides. In particular, electricity production from coal is one of the major sources of increased human exposure to naturally occurring radioactive materials. A methodology was developed to assess the radiological impact due to natural radiation background. The developed research was applied to a specific case study, the Sines coal-fired power plant, located in the southwest coastline of Portugal. Gamma radiation measurements were carried out with two different instruments: a sodium iodide scintillation detector counter (SPP2 NF, Saphymo) and a gamma ray spectrometer with energy discrimination (Falcon 5000, Canberra). Two circular survey areas were defined within 20 km of the power plant. Forty relevant measurements points were established within the sampling area: 15 urban and 25 suburban locations. Additionally, ten more measurements points were defined, mostly at the 20-km area. The registered gamma radiation varies from 20 to 98.33 counts per seconds (c.p.s.) corresponding to an external gamma exposure rate variable between 87.70 and 431.19 nGy/h. The highest values were measured at locations near the power plant and those located in an area within the 6 and 20 km from the stacks. In situ gamma radiation measurements with energy discrimination identified natural emitting nuclides as well as their decay products (Pb-212, Pb-2142, Ra-226, Th-232, Ac-228, Th-234, Pa-234, U- 235, etc.). According to the results, an influence from the stacks emissions has been identified both qualitatively and quantitatively. The developed methodology accomplished the lack of data in what concerns to radiation rate in the vicinity of Sines coal-fired power plant and consequently the resulting exposure to the nearby population. (authors)

  12. Lixiviation of natural radionuclides and heavy metals in tropical soils amended with phosphogypsum.

    PubMed

    Nisti, M B; Saueia, C R; Malheiro, L H; Groppo, G H; Mazzilli, B P

    2015-06-01

    The main phosphate industries in Brazil are responsible for the annual production of 5.5 million tons of a residue (phosphogypsum), which is stored in stacks. The presence of radionuclides and metals puts restrictions on the use of phosphogypsum in agriculture. To assure a safe utilization, it is important to estimate the lixiviation of the radionuclides ((238)U, (226)Ra, (210)Pb, (210)Po, (232)Th and (228)Ra) and metals (As, Cd, Cr, Ni, Se, Hg and Pb) present in phosphogypsum. For this purpose, an experiment was carried out, in which columns filled with sandy and clay Brazilian typical soils mixed with phosphogypsum were percolated with water, to achieve a mild extraction of these elements. The results obtained for the concentration of the radionuclides and metals in the leachate were low; giving evidence that, even when these elements are present in the phosphogypsum, they do not contribute to an enhancement of their content in water.

  13. Transfer of radionuclides to plants of natural ecosystems at the Semipalatinsk Test Site.

    PubMed

    Larionova, N V; Lukashenko, S N; Kabdyrakova, A M; Kunduzbayeva, A Ye; Panitskiy, A V; Ivanova, A R

    2017-10-06

    A systematic study devoted to (137)Cs, (90)Sr, (241)Am, (239+240)Pu radionuclides in vegetation cover from several spots of the Semipalatinsk test site (STS) is summarised in this paper, highlighting the main findings obtained. The analysed spots are characterized by various types of radioactive contamination. Transfer factors (Tf) required for the quantitative description of the radionuclides transition from the soil to aboveground plant parts were determined, being found that, on average, the minimum Tf for all the radionuclides concerned were determined on the "Experimental Field" ground, followed by the determined ones in the "plumes" of radioactive fallout and in the conditionally "background" territories analysed. The highest transfer factors were characteristic of zones of radioactive streamflows and places of warfare radioactive agent (WRA) tests. On the other hand, ordering the radionuclide transferring factors in descending order, the following sequence was obtained: (90)Sr Tf > Cs Tf > (239+240)Pu Tf > (241)Am Tf, with the (90)Sr Tf, on the average, exceeding the (137)Cs Tf by 8 times and exceeding the (239+240)Pu Tf by up 16 times. (239+240)Pu Tf values were up to 3 times higher than the (241)Am Tf. The exception to the indicated radionuclide Tf descending order corresponded to places of WRA tests where Tf of radionuclides of interest by plants follows the sequence (90)Sr > (239+240)Pu > (137)Cs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Assessment of indoor absorbed gamma dose rate from natural radionuclides in concrete by the method of build-up factors.

    PubMed

    Manić, Vesna; Nikezic, Dragoslav; Krstic, Dragana; Manić, Goran

    2014-12-01

    The specific absorbed gamma dose rates, originating from natural radionuclides in concrete, were calculated at different positions of a detection point inside the standard room, as well as inside an example room. The specific absorbed dose rates corresponding to a wall with arbitrary dimensions and thickness were also evaluated, and appropriate fitting functions were developed, enabling dose rate calculation for most realistic rooms. In order to make calculation simpler, the expressions fitting the exposure build-up factors for whole (238)U and (232)Th radionuclide series and (40)K were derived in this work, as well as the specific absorbed dose rates from a point source in concrete. Calculated values of the specific absorbed dose rates at the centre point of the standard room for (238)U, (232)Th and (40)K are in the ranges of previously obtained data. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. Unsaturated zone waters from the Nopal I natural analog, Chihuahua, Mexico -- Implications for radionuclide mobility at Yucca Mountain

    SciTech Connect

    Pickett, D.A.; Murphy, W.M.

    1999-07-01

    Chemical and U-Th isotopic data on unsaturated zone waters from the Nopal I natural analog reveal effects of water-rock interaction and help constrain models of radionuclide release and transport at the site and, by analogy, at the proposed nuclear waste repository at Yucca Mountain. Geochemical reaction-path modeling indicates that, under oxidizing conditions, dissolution of uraninite (spent fuel analog) by these waters will lead to eventual schoepite precipitation regardless of initial silica concentration provided that groundwater is not continuously replenished. Thus, less soluble uranyl silicates may not dominate the initial alteration assemblage and keep dissolved U concentrations low. Uranium-series activity ratios are consistent with models of U transport at the site and display varying degrees of leaching versus recoil mobilization. Thorium concentrations may reflect the importance of colloidal transport of low-solubility radionuclides in the unsaturated zone.

  16. Spatial and vertical distribution and risk assessment of natural radionuclides in soils surrounding the lignite-fired power plants in Megalopolis basin, Greece.

    PubMed

    Papaefthymiou, H V; Manousakas, M; Fouskas, A; Siavalas, G

    2013-01-01

    Twenty soil profile samples and fourteen surface soil samples collected from the vicinity of the lignite-fired power plants in the Megalopolis basin (Greece) were analysed for their natural radionuclide concentration and (137)Cs, since fossil fuels are associated with naturally occurring radioactive materials and hence with radiological impact. No significant enhancement of surface soil radioactivity levels in the vicinity of lignite-fired plants was observed. A downcore decreasing trend of (137)Cs was observed in a number of cores reflecting its atmospheric origin, whereas the uniform distribution observed in a number of other cores gave information on the mechanical alteration of the soil. The average dose rate value was found to be 63 ± 22 nGy h(-1), while the annual average effective dose from the terrestrial gamma radiation was found to be 0.08 ± 0.03 mSv.

  17. Survival of naturally occurring Campylobacter in refrigerated and frozen rinsate from a broiler carcass

    USDA-ARS?s Scientific Manuscript database

    The objective of this study was to determine if naturally occurring Campylobacter in a broiler rinsate could survive in cold storage. Ten commercial broiler carcasses were each rinsed with 500 ml of Butterfield’s buffer and all carcasses tested positive for the presence of 104-105/ml naturally occu...

  18. Tracing the origin of suspended sediment in a large Mediterranean river by combining continuous river monitoring and measurement of artificial and natural radionuclides.

    PubMed

    Zebracki, Mathilde; Eyrolle-Boyer, Frédérique; Evrard, Olivier; Claval, David; Mourier, Brice; Gairoard, Stéphanie; Cagnat, Xavier; Antonelli, Christelle

    2015-01-01

    Delivery of suspended sediment from large rivers to marine environments has important environmental impacts on coastal zones. In France, the Rhone River (catchment area of 98,000 km(2)) is by far the main supplier of sediment to the Mediterranean Sea and its annual solid discharge is largely controlled by flood events. This study investigates the relevance of alternative and original fingerprinting techniques based on the relative abundances of a series of radionuclides measured routinely at the Rhone River outlet to quantify the relative contribution of sediment supplied by the main tributaries during floods. Floods were classified according to the relative contribution of the main subcatchments (i.e., Oceanic, Cevenol, extensive Mediterranean and generalised). Between 2000 and 2012, 221 samples of suspended sediment were collected at the outlet and were shown to be representative of all flood types that occurred during the last decade. Three geogenic radionuclides (i.e., (238)U, (232)Th and (40)K) were used as fingerprints in a multivariate mixing model in order to estimate the relative contribution of the main subcatchment sources-characterised by different lithologies-in sediment samples collected at the outlet. Results showed that total sediment supply originating from Pre-Alpine, Upstream, and Cevenol sources amounted to 10, 7 and 2.10(6)tons, respectively. These results highlight the role of Pre-Alpine tributaries as the main sediment supplier (53%) to the Rhone River during floods. Other fingerprinting approaches based on artificial radionuclide activity ratios (i.e., (137)Cs/(239+240)Pu and (238)Pu/(239+240)Pu) were tested and provided a way to quantify sediment remobilisation or the relative contributions of the southern tributaries. In the future, fingerprinting methods based on natural radionuclides should be further applied to catchments with heterogeneous lithologies. Methods based on artificial radionuclides should be further applied to catchments

  19. Encapsulation of piceatannol, a naturally occurring hydroxylated analogue of resveratrol, by natural and modified cyclodextrins.

    PubMed

    Matencio, Adrián; García-Carmona, Francisco; López-Nicolás, José Manuel

    2016-05-18

    In this work, an in-depth study of the interaction between piceatannol (a type of stilbene with high biological activity) and different natural and modified cyclodextrins (CDs) is made, using steady state fluorescence. This bioactive molecule forms a 1 : 1 complex with all the natural (α-CD, β-CD and γ-CD) and modified (HP-β-CD, HE-β-CD and M-β-CD) CDs tested. Among natural CDs, the interaction of piceatannol with β-CD was the most efficient. However, the modified CDs showed higher encapsulation constants (KF) than β-CD, except M-β-CD; the highest KF being found for HP-β-CD (14 048 ± 702 M(-1)). The encapsulation of piceatannol in the internal cavity of CDs showed a strong dependence on pH and temperature. The interaction between HP-β-CD and piceatannol was less effective in the pH region where the stilbene begins to suffer the deprotonation of its hydroxyl group. Moreover, the values of KF decreased as the system temperature increased. To obtain information on the mechanism involved in the piceatannol affinity for CD, the thermodynamic parameters of the complexation (ΔH°, ΔS° and ΔG°) were studied, the results showed a negative entropy (-3.7 ± 0.2 J mol(-1) K(-1)), enthalpy (-24.6 ± 1.2 kJ mol(-1)) and Gibbs free energy change at 25 °C (-23.5 ± 1.2 J mol(-1)). Finally, molecular docking calculations provided further insights into how the different interactions influence the complexation constant. A high degree of correlation was observed between the computed scores and experimental values.

  20. Natural and active chemical remediation of toxic metals, organics, and radionuclides in the aquatic environment

    SciTech Connect

    McPherson, G.; Pintauro, P.; O`Connor, S.

    1996-05-02

    This project focuses on the chemical aspects of remediation, with the underlying theme that chemical remediation does occur naturally. Included are studies on the fate of heavy metal and organic contaminants discharged into aquatic environments; accurate assay metal contaminants partitioned into soils, water and tissue; development of novel polymeric membranes and microporous solids for the entrapment of heavy metals; and the development of hybrid chemo-enzymatic oxidative schemes for aromatics decontamination. 49 refs.

  1. Apoptosis and autophagy induction as mechanism of cancer prevention by naturally occurring dietary agents

    PubMed Central

    Mukhtar, Eiman; Adhami, Vaqar Mustafa; Khan, Naghma; Mukhtar, Hasan

    2013-01-01

    Nontoxic naturally occurring compounds, especially those from dietary sources, are receiving increasing consideration for prevention and treatment of diseases including cancer. There is a growing need for innovative anticancer therapies and therefore search for natural compounds with novel biological activities or antineoplastic potential is currently an important area in drug discovery. Support for this interest also comes from increasing concern over the efficacy and safety of many conventional therapies, especially those that run over a long course of time. Laboratory studies in different in vitro and in vivo systems have shown that many natural compounds possess the capacity to regulate response to oxidative stress and DNA damage, suppress angiogenesis, inhibit cell proliferation and induce autophagy and apoptosis. This review discusses the induction of apoptosis and autophagy as a mechanism of cancer prevention by some of the most studied naturally occurring dietary compounds. PMID:23140293

  2. Chemical constituents of peppers (Piper spp.) and application to food preservation: naturally occurring antioxidative compounds.

    PubMed Central

    Nakatani, N; Inatani, R; Ohta, H; Nishioka, A

    1986-01-01

    In a structure analysis of the compounds of the genus Piper (Family Piperaceae), we identified five phenolic amides from Piper nigrum, seven compounds from P. retrofractum, and two compounds from P. baccatum. All the phenolic amides possess significant antioxidant activities that are more effective than the naturally occurring antioxidant, alpha-tocopherol. One amide, feruperine, has antioxidant activity as high as the synthetic antioxidants, butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT). Naturally occurring antioxidants, therefore, may surpass BHA and BHT in their ability to inactivate mutagens in food. PMID:3757949

  3. A naturally occurring, noncanonical GTP aptamer made of simple tandem repeats

    PubMed Central

    Curtis, Edward A; Liu, David R

    2014-01-01

    Recently, we used in vitro selection to identify a new class of naturally occurring GTP aptamer called the G motif. Here we report the discovery and characterization of a second class of naturally occurring GTP aptamer, the “CA motif.” The primary sequence of this aptamer is unusual in that it consists entirely of tandem repeats of CA-rich motifs as short as three nucleotides. Several active variants of the CA motif aptamer lack the ability to form consecutive Watson-Crick base pairs in any register, while others consist of repeats containing only cytidine and adenosine residues, indicating that noncanonical interactions play important roles in its structure. The circular dichroism spectrum of the CA motif aptamer is distinct from that of A-form RNA and other major classes of nucleic acid structures. Bioinformatic searches indicate that the CA motif is absent from most archaeal and bacterial genomes, but occurs in at least 70 percent of approximately 400 eukaryotic genomes examined. These searches also uncovered several phylogenetically conserved examples of the CA motif in rodent (mouse and rat) genomes. Together, these results reveal the existence of a second class of naturally occurring GTP aptamer whose sequence requirements, like that of the G motif, are not consistent with those of a canonical secondary structure. They also indicate a new and unexpected potential biochemical activity of certain naturally occurring tandem repeats. PMID:24824832

  4. The detailed analysis of natural radionuclides dissolved in spa waters of the Kłodzko Valley, Sudety Mountains, Poland.

    PubMed

    Walencik-Łata, A; Kozłowska, B; Dorda, J; Przylibski, T A

    2016-11-01

    A survey was conducted to measure natural radioactivity in spa waters from the Kłodzko Valley. The main goal of this study was to determine the activity concentration of uranium, radium and radon isotopes in the investigated groundwaters. Samples were collected several times from 35 water intakes from 5 spas and 2 mineral water bottling plants. The authors examined whether the increased gamma radiation background, as well as the elevated values of radium and uranium content in reservoir rocks, have a significant impact on the natural radioactivity of these waters. The second objective of this research was to provide information about geochemistry of U, Ra, Rn radionuclides and the radiological and chemical risks incurred by ingestion of isotopes with drinking water. On the basis of results obtained, it is feasible to assess the health hazard posed by ingestion of natural radioactivity with drinking waters. Moreover, the data yielded by this research may be helpful in the process of verification of the application of these waters in balneotherapy. In addition, annual effective radiation doses resulting from the isotopes consumption were calculated on the basis of the evaluated activity concentrations. In dose assessment for uranium and radium isotopes, the authors provided values for different human age groups. The obtained uranium content in the investigated waters was compared with the currently valid regulations concerning the quality of drinking water. Based on the activity concentrations data, the activity isotopic ratios (234)U/(238)U, (226)Ra/(238)U, (222)Rn/(238)U, (222)Rn/(226)Ra and the correlations between radionuclides content were then examined. In brief, it may be concluded on the basis of the obtained results that radon solubility is inversely proportional to radium and uranium dissolution in environmental water circulation. The presented study allows conclusions to be drawn on the radionuclide circulation among different environmental biota: from

  5. Characterization of the National Petroleum Reserve No. 3 (NPR-3) Site for Naturally Occurring Radioactive Material(NORM)

    SciTech Connect

    White, G.J; Rood, A.S.

    1999-01-21

    The National Petroleum Reserve No. 3 site (NPR-3) near Casper, Wyoming is being prepared for transfer to private industry. Remediation of the NPR-3 site has already begun in anticipation of this transfer. This document describes the characterization of the NPR-3 site for Naturally Occurring Radioactive Materials (NORM). Data generated on radionuclide concentrations and radon emanation may be used to determine disposal options and the need for remediation at this site. A preliminary gamma survey of the NPR-3 site was conducted to identify areas of potential NORM contamination. Based on these gamma surveys, two general areas of NORM contamination were found: the North Water Flood area and the BTP-10 produced water discharge steam. A maximum surface exposure rate of 120 {micro}R h{sup -1} was observed in the North Water Flood area, with the highest readings found along the drainage channel from the area. Exposure rates dropped to background quickly with increasing distance from the center of the drainage. The maximum observed exposure rate in the BTP-10 produced water drainage was 40 {micro}R h{sup -1}. Soil and sediment sampling were concentrated in these two areas. All samples were analyzed for concentration of {sup 226}Ra, {sup 228}Ra, and {sup 40}K. Maximum {sup 226}Ra concentrations observed in the samples collected were 46 pCi g{sup -1} for soil and 78 pCi g{sup -1} for sediment. Concentrations in most samples were considerably lower than these values. Radon emanation fraction was also measured for a randomly selected fraction of the samples. The mean Rn emanation fraction measured was 0.10, indicating that on average only 10 percent of the Rn produced is released from the medium. Based on the results of these analyses, NORM contamination at the NPR-3 site is minimal, and appears to be restricted to the two general areas sampled. Concentrations of NORM radionuclides found soils and sediments in these two locations do not justify remedial actions at present

  6. A study of the dry heat resistance of naturally occurring organisms widely dispersed on a surface

    NASA Technical Reports Server (NTRS)

    Garst, D. M.; Lindell, K. F.

    1971-01-01

    Although Bacillus subtilis var. niger is the standard test organism for NASA planetary quarantine sterilization studies, it was found that some naturally occurring soil organisms are more heat resistant. The separation of these organisms from soil particles is described. Experiments are discussed which were designed to show that the heat resistance is a natural characteristic of the organisms, rather than a condition induced by the clumping effect of agglomerated particles and organisms.

  7. Application of natural radionuclides for determination of tropospheric ozone and aerosol transport.

    SciTech Connect

    Gaffney, J. S.; Marley, N. A.; Drayton, P. J.; Orlandini, K. A.

    2000-12-06

    Natural radionuclides have been proposed for use in assessing the transport of ozone and aerosols in the troposphere. For example, {sup 7}Be is known to be produced in the upper troposphere and lower stratosphere by interactions with cosmogenic particles. Beryllium-7 has a 53.28-day half-life and is a gamma emitter that attaches itself to fine particles in the atmosphere once it is formed. Indeed, in tropospheric aerosol samples TBe is typically found in association with aerosol particles that are 0.3 {micro}m in diameter. Some investigators have asserted that ozone from aloft can be transported into rural and urban regions during stratospheric/tropospheric folding events, leading to increased background levels of ozone. During the Texas 2000 Air Quality study, aerosol samples with a 2.5-{micro}m cutoff were collected during 12-hour cycles (day/night) for a 30-day period at the Deer Park, Texas, field site in August-September 2000. To monitor {sup 7}Be levels, high-volume samples were collected on glass fiber filters on Julian dates 225-259. Sample collection was at a field site near a city park, away from any nearby traffic. This site is under routine operation by the Texas Natural Resource Conservation Commission. Instruments operated at this same site during the study period included an ozone monitor (Dasibi), a nitrogen oxides instrument (API), a CO instrument (API), a nephelometer, a UV-B meter (Richardson-Berger), and a multifilter rotating shadow band radiometer (MFRSR, Yankee Environmental Systems). In addition, we made modified fast-response NO{sub 2} and peroxyacetyl nitrate (PAN) measurements by using a fast gas chromatography with luminol detection, to be described at this meeting (3). The results for {sup 7}Be (mBq m{sup {minus}3})are compared in Figure 1 with the maximum and average ozone values (ppb) observed at the site to identify potential correlations. In Figure 2, all of the {sup 7}Be data are plotted against the maximum and average ozone

  8. Recent advances in the detection of specific natural organic compounds as carriers for radionuclides in soil and water environments, with examples of radioiodine and plutonium

    DOE PAGES

    Santschi, P. H.; Xu, C.; Zhang, S.; ...

    2017-03-09

    Among the key environmental factors influencing the fate and transport of radionuclides in the environment is natural organic matter (NOM). While this has been known for decades, there still remains great uncertainty in predicting NOM-radionuclide interactions because of lack of understanding of radionuclide interactions with the specific organic moieties within NOM. Furthermore, radionuclide-NOM studies conducted using modelled organic compounds or elevated radionuclide concentrations provide compromised information related to true environmental conditions. Thus, sensitive techniques are required not only for the detection of radionuclides, and their different species, at ambient and/or far-field concentrations, but also for potential trace organic compounds thatmore » are chemically binding these radionuclides. GC-MS and AMS techniques developed in our lab are reviewed in this paper that aim to assess how two radionuclides, iodine and plutonium, form strong bonds with NOM by entirely different mechanisms; iodine tends to bind to aromatic functionalities, whereas plutonium binds to N-containing hydroxamate siderophores at ambient concentrations. While low-level measurements are a prerequisite for assessing iodine and plutonium migration at nuclear waste sites and as environmental tracers, it is necessary to determine their in-situ speciation, which ultimately controls their mobility and transport in natural environments. Finally and more importantly, advanced molecular-level instrumentation (e.g., nuclear magnetic resonance (NMR) and Fourier-transform ion cyclotron resonance coupled with electrospray ionization (ESI-FTICRMS) were applied to resolve either directly or indirectly the molecular environments in which the radionuclides are associated with the NOM.« less

  9. Radionuclide Therapy

    NASA Astrophysics Data System (ADS)

    Zalutsky, M. R.

    Radionuclide therapy utilizes unsealed sources of radionuclides as a treatment for cancer or other pathological conditions such as rheumatoid arthritis. Radionuclides that decay by the emission of β and α particles, as well as those that emit Auger electrons, have been used for this purpose. In this chapter, radiochemical aspects of radionuclide therapy, including criteria for radionuclide selection, radionuclide production, radiolabeling chemistry, and radiation dosimetry are discussed.

  10. Comparison of selective media for detection and enumeration of naturally occurring Campylobacter spp. on poultry

    USDA-ARS?s Scientific Manuscript database

    Introduction: Campylobacter spp. are known to be among the most common bacteria to cause diarrheal illness, with poultry being linked as the primary source of contamination related to foodborne illness. Enumeration and detection of low numbers of naturally occurring Campylobacter spp. on poultry pro...

  11. Therapeutic Recreation in the Naturally Occurring Retirement Community (NORC): Benefitting "Aging in Place."

    ERIC Educational Resources Information Center

    Kunstler, Robin

    2002-01-01

    Describes how therapeutic recreation in naturally occurring retirement communities (neighborhoods where most residents are older) can promote healthy lifestyles, presenting a case report of an in-home therapeutic recreation program offered in conjunction with nursing and social services in a such a community and discussing implications for…

  12. Survival of naturally occurring Campylobacter in refrigerated and frozen rinsate from a broiler carcass

    USDA-ARS?s Scientific Manuscript database

    The objective of this study was to determine if naturally occurring Campylobacter in a broiler carcass rinsate could survive in cold or frozen storage. Ten commercial broiler carcasses were each rinsed with 500 ml of Butterfield’s buffer and all carcasses tested positive for the presence of 104-105...

  13. Comparison of Selective Campylobacter Media for Detection and Enumeration of Naturally Occurring Campylobacter spp. on Poultry

    USDA-ARS?s Scientific Manuscript database

    Campylobacter spp. are among the most common cause of bacterial foodborne diarrheal illness; poultry has been linked as a primary source of contamination. Detection and enumeration of low numbers of naturally occurring Campylobacter spp. on poultry is difficult due to the presence of competing micro...

  14. Naturally occurring vapor-liquid-solid (VLS) Whisker growth of germanium sulfide

    USGS Publications Warehouse

    Finkelman, R.B.; Larson, R.R.; Dwornik, E.J.

    1974-01-01

    The first naturally occurring terrestrial example of vapor-liquid-solid (VLS) growth has been observed in condensates from gases released by burning coal in culm banks. Scanning electron microscopy, X-ray diffraction, and energy dispersive analysis indicate that the crystals consist of elongated rods (??? 100 ??m) of germanium sulfide capped by bulbs depleted in germanium. ?? 1974.

  15. Subject Reaction to Human-Caused and Naturally-Occurring Radioactive Threat.

    ERIC Educational Resources Information Center

    Belford, Susan; Gibbs, Margaret

    While research has shown that people are adversely psychologically affected by knowledge that their communities have been toxically contaminated, it has been suggested that those who see a disaster as naturally occurring tend to be less adversely affected than those who see a disaster as caused by human acts. To examine this issue, questionnaires…

  16. MALDI-TOF Mass Spectrometry of Naturally-Occurring Mixtures of Mono- and Di-rhamnolipids

    USDA-ARS?s Scientific Manuscript database

    Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been developed for high-throughput screening of naturally-occurring mixtures of rhamnolipids from Pseudomonas spp. Mono- and di-rhamnolipids are readily distinguished by characteristic molecular adduct i...

  17. Does Naturally Occurring Comprehension Strategies Instruction Make a Difference when Students Read Expository Text?

    ERIC Educational Resources Information Center

    Braten, Ivar; Anmarkrud, Oistein

    2013-01-01

    The present study examined whether observed differences in naturally occurring classroom instruction of reading comprehension strategies were reflected in students' independent use of strategies to comprehend expository text. Based on a descriptive classroom study in 4 ninth-grade language arts classrooms, participants were divided into two groups…

  18. A library screening approach identifies naturally occurring RNA sequences for a G-quadruplex binding ligand.

    PubMed

    Mirihana Arachchilage, Gayan; Morris, Mark J; Basu, Soumitra

    2014-02-07

    An RNA G-quadruplex library was synthesised and screened against kanamycin A as the ligand. Naturally occurring G-quadruplex forming sequences that differentially bind to kanamycin A were identified and characterized. This provides a simple and effective strategy for identification of potential intracellular G-quadruplex targets for a ligand.

  19. Characterization of Contaminant Transport using Naturally-Occurring U-Series Disequilibria - Final Report - 05/01/1997 - 04/30/2001

    SciTech Connect

    Murrell, Michael T.; Ku, Teh-Lung

    2001-04-30

    The interactions of mixed wastes containing radionuclides with solid rock surface and the mobility of the radionuclides in aquifer systems depend not only on the chemistry of the nuclides and the physico-chemical effects of radioactive decay, but also on the site-specific hydrogeology. Thus, to characterize contaminant transport, it is best to cross-check figures derived from any small-scale laboratory experiments over limited times with that obtained from field-oriented, natural analog studies. We propose such a study using the naturally-occurring U and Th decay-series disequilibria. The work of ours and other researchers have shown that the parent/daughter disequilibrium patterns existing in groundwater systems can be modeled in terms of local nuclide mass balance to arrive at such information as the rock-water contact time (fluid flow) and rates of contaminant transport, taking into account the retardation effect due to nuclide/rock interaction contaminants at INEL by grouping them into three categories, represented by isotopes of (1) Th and Pa, (2) U and (3) Ra. Mass spectrometric measurements of these elements will be emphasized in order to minimize sample size requirements and to maximize precision. Results will form the data base for a model code for computing: (1) Fluid residence time (transport rates) in the basalt aquifers at various locations, (2) The in-situ adsorption and desorption rate constants, as well as the retardation factors, of various radionuclide wastes, and (3) Rock dissolution rate and its relation to preferential flow and contamination transport in the fractured rock.

  20. Recent Advances in the Chemistry and Biology of Naturally Occurring Antibiotics

    PubMed Central

    Chen, Jason S.; Edmonds, David J.; Estrada, Anthony A.

    2009-01-01

    Lead-in Ever since the world-shaping discovery of penicillin, nature’s molecular diversity has been extensively screened for new medications and lead compounds in drug discovery. The search for anti-infective agents intended to combat infectious diseases has been of particular interest and has enjoyed a high degree of success. Indeed, the history of antibiotics is marked with impressive discoveries and drug development stories, the overwhelming majority of which have their origins in nature. Chemistry, and in particular chemical synthesis, has played a major role in bringing naturally occurring antibiotics and their derivatives to the clinic, and no doubt these disciplines will continue to be key enabling technologies for future developments in the field. In this review article, we highlight a number of recent discoveries and advances in the chemistry, biology, and medicine of naturally occurring antibiotics, with particular emphasis on the total synthesis, analog design, and biological evaluation of molecules with novel mechanisms of action. PMID:19130444

  1. Distribution of naturally occurring radioactivity and ¹³⁷Cs in the marine sediment of Farasan Island, southern Red Sea, Saudi Arabia.

    PubMed

    Al-Zahrany, A A; Farouk, M A; Al-Yousef, A A

    2012-11-01

    The present work is a part of a project dedicated to measure the marine radioactivity near the Saudi Arabian coasts of the Red Sea and Arabian Gulf for establishing a marine radioactivity database, which includes necessary information on the background levels of both naturally occurring and man-made radionuclides in the marine environment. Farasan Islands is a group of 84 islands (archipelago), under the administration of the Kingdom of Saudi Arabia, in the Red Sea with its main island of Farasan, which is 50 km off the coast of Jazan City. The levels of natural radioactivity of (238)U, (235)U, (226)Ra, (232)Th and (40)K and man-made radionuclides such as (137)Cs in the grab sediment and water samples around Farasan Island have been measured using gamma-ray spectroscopy. The average activity concentrations of (238)U, (235)U, (226)Ra, (232)Th, (40)K and (137)Cs in the sediment samples were found to be 35.46, 1.75, 3.31, 0.92, 34.34 and 0.14 Bq kg(-1), respectively.

  2. Activity concentration of natural radionuclides and radon and thoron exhalation rates in rocks used as decorative wall coverings in Japan.

    PubMed

    Iwaoka, Kazuki; Hosoda, Masahiro; Tabe, Hiroyuki; Ishikawa, Tetsuo; Tokonami, Shinji; Yonehara, Hidenori

    2013-01-01

    In Japan, many dwellings have decorative wall coverings made from granite, andesite, tuff, gabbro, and marble. However, information regarding activity concentrations and radon (Rn) and thoron (Rn) exhalation rates for such rocks is very scarce. Therefore, samples of the granite, andesite, tuff, and marble that are used as wall coverings in Japan were collected from mining companies, and their activity concentrations and Rn and Rn exhalation rates were measured. Dose estimations for inhabitants living in houses built with these materials were also carried out. The activity concentration of natural radionuclides in all the materials was lower than the critical values described by the International Atomic Energy Agency (IAEA) (10,000 Bq kg for K and 1,000 Bq kg for all other radionuclides of natural origin). The maximum values of Rn and Rn mass exhalation rates for the granite samples were 0.12 and 430 mBq kg s, and those for the area exhalation rates were 1.8 and 6300 mBq m s, respectively; these values are higher than those for other samples. The maximum value of effective doses to inhabitants was 0.68 mSv y, which is lower than the intervention exemption level (1 mSv y) given in the International Commission on Radiological Protection (ICRP) Publication 82.

  3. The environmental geochemistry of trace elements and naturally radionuclides in a coal gangue brick-making plant.

    PubMed

    Zhou, Chuncai; Liu, Guijian; Cheng, Siwei; Fang, Ting; Lam, Paul K S

    2014-08-28

    An investigation focused on the transformation and distribution behaviors of trace elements and natural radionuclides around a coal gangue brick plant was conducted. Simultaneous sampling of coal gangue, brick, fly ash and flue gas were implemented. Soil, soybean and earthworm samples around the brick plant were also collected for comprehensive ecological assessment. During the firing process, trace elements were released and redistributed in the brick, fly ash and the flue gas. Elements can be divided into two groups according to their releasing characteristics, high volatile elements (release ratio higher than 30%) are represented by Cd, Cu, Hg, Pb, Se and Sn, which emitted mainly in flue gas that would travel and deposit at the northeast and southwest direction around the brick plant. Cadmium, Ni and Pb are bio-accumulated in the soybean grown on the study area, which indicates potential health impacts in case of human consumption. The high activity of natural radionuclides in the atmosphere around the plant as well as in the made-up bricks will increase the health risk of respiratory system.

  4. First intercomparison among laboratories involved in COST Action-TU1301 "NORM4Building": Determination of natural radionuclides in ceramics.

    PubMed

    Xhixha, Gerti; Trinidad, José Antonio; Gascó, Catalina; Mantovani, Fabio

    2017-03-01

    This work describes the outcomes of the COST Action-TU1301 "NORM4Building" intercomparison on the determination of natural radioactivity in ceramics. Twenty-two laboratories involved in the intercomparison are evaluated for their performance using robust statistics. The reference values of (226)Ra ((214)Bi and (214)Pb) are determined to be 122 ± 11 Bq kg(-1) and 124 ± 14 Bq kg(-1), respectively and in secular equilibrium in the uranium chain while the reference values of (232)Th ((228)Ac) is determined to be 61 ± 6 Bq kg(-1) and that of (40)K was determined to be 955 ± 40 Bq kg(-1). Although the aim of the exercise was to determine the activity concentration of (226)Ra, (232)Th and (40)K and evaluation of the "Activity Concentration Index", laboratories were asked to report complete characterization of natural radionuclides. The results of this exercise pointed out a good performance among laboratories since the percentage of the acceptable results were above 90% for the radionuclides of interest. Based on these results, considering the systematic rejection of the results reported from a few laboratories we emphasize the need for quality control procedures.

  5. The Environmental Geochemistry of Trace Elements and Naturally Radionuclides in a Coal Gangue Brick-Making Plant

    PubMed Central

    Zhou, Chuncai; Liu, Guijian; Cheng, Siwei; Fang, Ting; Lam, Paul K. S.

    2014-01-01

    An investigation focused on the transformation and distribution behaviors of trace elements and natural radionuclides around a coal gangue brick plant was conducted. Simultaneous sampling of coal gangue, brick, fly ash and flue gas were implemented. Soil, soybean and earthworm samples around the brick plant were also collected for comprehensive ecological assessment. During the firing process, trace elements were released and redistributed in the brick, fly ash and the flue gas. Elements can be divided into two groups according to their releasing characteristics, high volatile elements (release ratio higher than 30%) are represented by Cd, Cu, Hg, Pb, Se and Sn, which emitted mainly in flue gas that would travel and deposit at the northeast and southwest direction around the brick plant. Cadmium, Ni and Pb are bio-accumulated in the soybean grown on the study area, which indicates potential health impacts in case of human consumption. The high activity of natural radionuclides in the atmosphere around the plant as well as in the made-up bricks will increase the health risk of respiratory system. PMID:25164252

  6. The Environmental Geochemistry of Trace Elements and Naturally Radionuclides in a Coal Gangue Brick-Making Plant

    NASA Astrophysics Data System (ADS)

    Zhou, Chuncai; Liu, Guijian; Cheng, Siwei; Fang, Ting; Lam, Paul K. S.

    2014-08-01

    An investigation focused on the transformation and distribution behaviors of trace elements and natural radionuclides around a coal gangue brick plant was conducted. Simultaneous sampling of coal gangue, brick, fly ash and flue gas were implemented. Soil, soybean and earthworm samples around the brick plant were also collected for comprehensive ecological assessment. During the firing process, trace elements were released and redistributed in the brick, fly ash and the flue gas. Elements can be divided into two groups according to their releasing characteristics, high volatile elements (release ratio higher than 30%) are represented by Cd, Cu, Hg, Pb, Se and Sn, which emitted mainly in flue gas that would travel and deposit at the northeast and southwest direction around the brick plant. Cadmium, Ni and Pb are bio-accumulated in the soybean grown on the study area, which indicates potential health impacts in case of human consumption. The high activity of natural radionuclides in the atmosphere around the plant as well as in the made-up bricks will increase the health risk of respiratory system.

  7. Biopolyester-based systems containing naturally occurring compounds with enhanced thermo-oxidative stability.

    PubMed

    Arrigo, Rossella; Morici, Elisabetta; Dintcheva, Nadka Tzankova

    2016-11-02

    This work presents a sustainable approach for the stabilization of polylactic acid (PLA) against thermo-oxidative aging. Naturally occurring phenolic and polyphenolic compounds, such as ferulic acid (FerAc), vanillic acid (VanAc), quercetin (Querc) and vitamin E (VitE), were introduced into PLA. The preliminary characterization of the systems formulated containing different amounts of natural stabilizers showed that all compounds used acted as plasticizers, leading to a decrease in rheological functions with respect to neat PLA, without significantly modifying the crystallinity of the raw material. The study of the thermo-oxidative behavior of neat PLA and PLA/natural compound systems, performed by spectrometric and thermal analyses, indicated that all stabilizers considered were able to exert a remarkable antioxidant action against thermo-oxidative phenomena. All natural compounds considered are thus proposed as ecofriendly stabilizers, to get fully bio-based polymer systems with enhanced thermo-oxidative stability, suitable for biomedical applications.

  8. Distribution of Natural (U-238, Th-232, Ra-226) and Technogenic (Sr-90, Cs-137) Radionuclides in Soil-Plants Complex Near Issyk-Kul Lake, Kyrgyzstan

    NASA Astrophysics Data System (ADS)

    Jovanovic, L.; Kaldybaev, B.; Djenbaev, B.; Tilenbaev, A.

    2012-04-01

    Researches on radionuclides distribution in the soil-plants complex provide essential information in understanding human exposure to natural and technogenic sources of radiation. It is necessary in establishing regulation relating to radiation protection. The aim of this study was the radiochemical analysis of the content natural radionuclides 238U, 232Th,226Ra and technogenic radionuclides content (90Sr, 137Cs) in soils near Issyk-Kul lake (Kyrgyzstan). Results of radiochemical analyses have shown, that the concentrations of thorium-232 are fluctuating in the limits (11.7-84.1)-10-4% in the soils. The greatest concentration of thorium-232 has been found in the light chestnut soils. The content of uranium-238 in the soils near Issyk-Kul lake is fluctuating from 2.8 up to 12.7-10-4%. Radium-226 has more migration ability in comparison with other heavy natural radionuclides. According to our research the concentrations of radium-226 are fluctuating in the limits (9.4-43.0)-10-11%. The greatest concentration of radium-226 (43,0±2,8)-10-11% has been determined in the light chestnut soil. In connection with global migration of contaminating substances, including radioactive, the special attention is given long-lived radionuclides strontium-90 and caesium-137 in food-chains, and agroecosystems. Results of radiochemical analyses have shown, that specific activity of strontium-90 is fluctuating in the range of 2.9 up to 11.1 Bq/kg, and caesium-137 from 3.7 up to 14,3 Bq/kg in the soil of agroecosystems in the region of Issyk-Kul. In soil samples down to 1 meter we have observed vertical migration of these radionuclides, they were found to accumulate on the surface of soil horizon (0-5 cm) and their specific activity sharply decreases with depth. In addition in high-mountain pastures characterized by horizontal migration of cattle in profiles of soil, it was discovered that specific activity of radionuclides are lower on the slope than at the foot of the mountain. The

  9. Interaction of flavonoids, the naturally occurring antioxidants with different media: A UV-visible spectroscopic study

    NASA Astrophysics Data System (ADS)

    Naseem, Bushra; Shah, S. W. H.; Hasan, Aurangzeb; Sakhawat Shah, S.

    2010-04-01

    Quantitative parameters for interaction of flavonoids—the naturally occurring antioxidants, with solvents and surfactants are determined using UV-visible absorption spectroscopy. The availability of flavonoids; kaempferol, apigenin, kaempferide and rhamnetin in micelles of sodium dodecyl sulfate (SDS) is reflected in terms of partition coefficient, Kc. Thermodynamic calculations show that the process of transfer of flavonoid molecules to anionic micelles of SDS is energy efficient. A distortion in flavonoid's morphology occurs in case of kaempferol and apigenin in surfactant and water, exhibited in terms of a new band in the UV region of electronic spectra of these flavonoids. The partition coefficients of structurally related flavonoids are correlated with their antioxidant activities.

  10. Size dependent fluorescence tuning of naturally occurring betacyanin with silver nano particles

    NASA Astrophysics Data System (ADS)

    Sarkar, Arindam; Thankappan, Aparna; Nampoori, V. P. N.

    2014-10-01

    Light absorption and scattering of metal nano partilces occur in very narrow range of wavelengths. This is also dependent on the geometry and shape of metal nano particles. It is also known that scattering is related to (volume)2 and absorption is related to the volume of the spherical metal nano particles. In our work we show that using this principle metal nano particles enable fluorescence tuning of dyes. In our experiment we show such tuning in naturally occurring betacyanin extracted from red beetroot. We also show that such tuning is dependent on the size variation of the silver nano particles.

  11. Using naturally occurring tumours in dogs and cats to study telomerase and cancer stem cell biology.

    PubMed

    Pang, Lisa Y; Argyle, David J

    2009-04-01

    The recently described cancer stem cell theory opens up many new challenges and opportunities to identify targets for therapeutic intervention. However, the majority of cancer related therapeutic studies rely upon rodent models of human cancer that rarely translate into clinical success in human patients. Naturally occurring cancers in dogs, cats and humans share biological features, including molecular targets, telomerase biology and tumour genetics. Studying cancer stem cell biology and telomere/telomerase dynamics in the cancer bearing pet population may offer the opportunity to develop a greater understanding of cancer biology in the natural setting and evaluate the development of novel therapies targeted at these systems.

  12. A Review on the Phytochemistry, Pharmacology, and Pharmacokinetics of Amentoflavone, a Naturally-Occurring Biflavonoid.

    PubMed

    Yu, Sheng; Yan, Hui; Zhang, Li; Shan, Mingqiu; Chen, Peidong; Ding, Anwei; Li, Sam Fong Yau

    2017-02-16

    Amentoflavone (C30H18O10) is a well-known biflavonoid occurring in many natural plants. This polyphenolic compound has been discovered to have some important bioactivities, including anti-inflammation, anti-oxidation, anti-diabetes, and anti-senescence effects on many important reactions in the cardiovascular and central nervous system, etc. Over 120 plants have been found to contain this bioactive component, such as Selaginellaceae, Cupressaceae, Euphorbiaceae, Podocarpaceae, and Calophyllaceae plant families. This review paper aims to profile amentoflavone on its plant sources, natural derivatives, pharmacology, and pharmacokinetics, and to highlight some existing issues and perspectives in the future.

  13. Effect of fermentation on naturally occurring deoxynivalenol (DON) in Argentinean bread processing technology.

    PubMed

    Samar, M M; Neira, M S; Resnik, S L; Pacin, A

    2001-11-01

    The stability of naturally occurring DON was evaluated during the fermentation stage of the bread-making process on a pilot scale. Two different products, French bread and Vienna bread, were prepared with naturally contaminated wheat flour (150 mg kg(-1)) under controlled experimental conditions. Dough was fermented at 30, 40 and 50 degrees C according to standard procedures employed in Argentinean low-technology bakeries. When the dough was fermented at 50 degrees C, the maximum reduction was 56% for the Vienna bread, with French bread being reduced by 41%. DON reduction during bread-making occurs not only in the baker due to thermal decomposition, but also during the fermentation step. The Argentinean traditional bread-making process might reduce DON levels during the fermentation stages if the dough is leavened at temperatures > 30 degrees C.

  14. Prospective trial of metronomic chlorambucil chemotherapy in dogs with naturally occurring cancer.

    PubMed

    Leach, T N; Childress, M O; Greene, S N; Mohamed, A S; Moore, G E; Schrempp, D R; Lahrman, S R; Knapp, D W

    2012-06-01

    The purpose of this study was to assess the toxicoses and antitumor activity of metronomic chlorambucil at a dosage of 4 mg m(-2) daily in dogs with naturally occurring cancer. Thirty-six dogs were enrolled in the study. The protocol was well tolerated with no grade 3 or 4 toxicoses noted. Complete remission was achieved, and lasted over 35 weeks in three dogs (mast cell tumour, soft tissue sarcoma and thyroid carcinoma). Partial remission was noted in 1 dog with histiocytic sarcoma (39 weeks duration) for an overall remission rate of 11% (4 of 36). Stable disease was noted in 17 dogs (47%) with various other cancers. The median progression-free interval was 61 days, and the median survival time was 153 days. Chlorambucil given in a metronomic protocol showed antitumor activity in dogs with a variety of naturally occurring cancers. © 2011 Blackwell Publishing Ltd.

  15. Playing 'Tetris' reduces the strength, frequency and vividness of naturally occurring cravings.

    PubMed

    Skorka-Brown, Jessica; Andrade, Jackie; May, Jon

    2014-05-01

    Elaborated Intrusion Theory (EI) postulates that imagery is central to craving, therefore a visually based task should decrease craving and craving imagery. This study provides the first laboratory test of this hypothesis in naturally occurring, rather than artificially induced, cravings. Participants reported if they were experiencing a craving and rated the strength, vividness and intrusiveness of their craving. They then either played 'Tetris' or they waited for a computer program to load (they were told it would load, but it was designed not to). Before task completion, craving scores between conditions did not differ; after, however, participants who had played 'Tetris' had significantly lower craving and less vivid craving imagery. The findings support EI theory, showing that a visuospatial working memory load reduces naturally occurring cravings, and that Tetris might be a useful task for tackling cravings outside the laboratory. Methodologically, the findings show that craving can be studied in the laboratory without using craving induction procedures.

  16. Structural consequences of chromophore formation and exploration of conserved lid residues amongst naturally occurring fluorescent proteins

    NASA Astrophysics Data System (ADS)

    Zimmer, Matthew H.; Li, Binsen; Shahid, Ramza; Peshkepija, Paola; Zimmer, Marc

    2014-01-01

    Computational methods were used to generate the lowest energy conformations of the immature precyclized forms of the 28 naturally occurring GFP-like proteins deposited in the pdb. In all 28 GFP-like proteins, the beta-barrel contracts upon chromophore formation and becomes more rigid. Our prior analysis of over 260 distinct naturally occurring GFP-like proteins revealed that most of the conserved residues are located in the top and bottom of the barrel in the turns between the β-sheets (Ong et al. 2011) [1]. Structural analyses, molecular dynamics simulations and the Anisotropic Network Model were used to explore the role of these conserved lid residues as possible folding nuclei. Our results are internally consistent and show that the conserved residues in the top and bottom lids undergo relatively less translational movement than other lid residues, and a number of these residues may play an important role as hinges or folding nuclei in the fluorescent proteins.

  17. Effects of fire on naturally occurring blue oak (Quercus douglasii) saplings

    Treesearch

    Tedmund J. Swiecki; Elizabeth Bernhardt

    2002-01-01

    We studied the survival and regrowth of naturally-occurring blue oak saplings burned in a September 1996 arson fire in Vacaville, California. The saplings (pre-fire height 33-353 cm) were burned in a rapid, low-moderate intensity fire. Of 67 blue oak saplings surveyed, 4 failed to resprout after the fire and 2 more died within the following 5 years (9 percent mortality...

  18. Pyrethroid insecticides: A naturally occurring toxin. (Latest citations from Pollution Abstracts). Published Search

    SciTech Connect

    Not Available

    1993-05-01

    The bibliography contains citations concerning the effects of pyrethrum and pyrethroid insecticides. Topics examine toxicity to fish, worms, flies, mosquitoes, and moths. Chemical residue on crops, the transportation of pyrethrum from soils to crops, and pyrethrum accumulation in ponds and lakes are among the topics discussed. Naturally occurring and synthetic pyrethroid insecticides are included. (Contains a minimum of 173 citations and includes a subject term index and title list.)

  19. Effect of Microbial and Other Naturally Occurring Polymers on Mineral Dissolution

    SciTech Connect

    Welch, S. A.; Vandevivere, P.

    1994-11-21

    Several naturally occurring polymers were tested for their effect on mineral dissolution. Polymers composed primarily of neutral sugars had no effect on dissolution, even at concentrations 1000 times greater than average dissolved organic carbon concentrations found in groundwater. In contrast, alginate, a polysaccharide composed of two uronic acids, inhibited dissolution by 80% at the highest concentration used. A high-molecular-weight polyaspartate also inhibited dissolution, though a lower-molecular-weight polyaspartate had no affect.

  20. Natural occurring 2-(2-phenylethyl) chromones, structure elucidation and biological activities.

    PubMed

    Ibrahim, Sabrin R M; Mohamed, Gamal A

    2015-01-01

    2-(2-Phenylethyl) chromone (PEC), an uncommon class of chromones, possesses a phenylethyl substituent at the C2 position. They have been isolated from a few plant species. They have promising biological activities such as neuro-protective, cytotoxic, acetylcholinesterase inhibitory, antibacterial and anti-inflammatory. This review focuses on the naturally occurring PEC derivatives, their sources, physical and spectral data, as well as biological activities.

  1. Interleukin-31: its role in canine pruritus and naturally occurring canine atopic dermatitis.

    PubMed

    Gonzales, Andrea J; Humphrey, William R; Messamore, James E; Fleck, Timothy J; Fici, Gregory J; Shelly, John A; Teel, Janet F; Bammert, Gary F; Dunham, Steven A; Fuller, Troy E; McCall, Robert B

    2013-02-01

    Interleukin-31 (IL-31) is a member of the gp130/interleukin-6 cytokine family that is produced by cell types such as T helper 2 lymphocytes and cutaneous lymphocyte antigen positive skin homing T cells. When overexpressed in transgenic mice, IL-31 induces severe pruritus, alopecia and skin lesions. In humans, IL-31 serum levels correlate with the severity of atopic dermatitis in adults and children. To determine the role of IL-31 in canine pruritus and naturally occurring canine atopic dermatitis (AD). Purpose-bred beagle dogs were used for laboratory studies. Serum samples were obtained from laboratory animals, nondiseased client-owned dogs and client-owned dogs diagnosed with naturally occurring AD. Purpose-bred beagle dogs were administered canine interleukin-31 (cIL-31) via several routes (intravenous, subcutaneous or intradermal), and pruritic behaviour was observed/quantified via video monitoring. Quantitative immunoassay techniques were employed to measure serum levels of cIL-31 in dogs. Injection of cIL-31 into laboratory beagle dogs caused transient episodes of pruritic behaviour regardless of the route of administration. When evaluated over a 2 h period, dogs receiving cIL-31 exhibited a significant increase in pruritic behaviour compared with dogs that received placebo. In addition, cIL-31 levels were detectable in 57% of dogs with naturally occurring AD (≥ 13 pg/mL) but were below limits of quantification (<13 pg/mL) in normal, nondiseased laboratory or client-owned animals. Canine IL-31 induced pruritic behaviours in dogs. Canine IL-31 was detected in the majority of dogs with naturally occurring AD, suggesting that this cytokine may play an important role in pruritic allergic skin conditions, such as atopic dermatitis, in this species. © 2013 Pfizer Inc. Veterinary Dermatology © 2013 ESVD and ACVD.

  2. Segregation of Naturally Occurring Mitochondrial DNA Variants in a Mini-Pig Model.

    PubMed

    Cagnone, Gael; Tsai, Te-Sha; Srirattana, Kanokwan; Rossello, Fernando; Powell, David R; Rohrer, Gary; Cree, Lynsey; Trounce, Ian A; St John, Justin C

    2016-03-01

    The maternally inherited mitochondrial genome (mtDNA) is present in multimeric form within cells and harbors sequence variants (heteroplasmy). While a single mtDNA variant at high load can cause disease, naturally occurring variants likely persist at low levels across generations of healthy populations. To determine how naturally occurring variants are segregated and transmitted, we generated a mini-pig model, which originates from the same maternal ancestor. Following next-generation sequencing, we identified a series of low-level mtDNA variants in blood samples from the female founder and her daughters. Four variants, ranging from 3% to 20%, were selected for validation by high-resolution melting analysis in 12 tissues from 31 animals across three generations. All four variants were maintained in the offspring, but variant load fluctuated significantly across the generations in several tissues, with sex-specific differences in heart and liver. Moreover, variant load was persistently reduced in high-respiratory organs (heart, brain, diaphragm, and muscle), which correlated significantly with higher mtDNA copy number. However, oocytes showed increased heterogeneity in variant load, which correlated with increased mtDNA copy number during in vitro maturation. Altogether, these outcomes show that naturally occurring mtDNA variants segregate and are maintained in a tissue-specific manner across generations. This segregation likely involves the maintenance of selective mtDNA variants during organogenesis, which can be differentially regulated in oocytes and preimplantation embryos during maturation.

  3. Mechanisms and Modifications of Naturally Occurring Host Defense Peptides for Anti-HIV Microbicide Development

    PubMed Central

    Eade, Colleen R.; Wood, Matthew P.; Cole, Alexander M.

    2014-01-01

    Despite advances in the treatment of HIV infection, heterosexual transmission of HIV remains high, and vaccines to prevent HIV acquisition have been unfruitful. Vaginal microbicides, on the other hand, have demonstrated considerable potential for HIV prevention, and a variety of compounds have been screened for their activity and safety as anti-HIV microbicides. Among these are the naturally occurring host defense peptides, small peptides from diverse lineages with intrinsic antiviral activity. Naturally occurring host defense peptides with anti-HIV activity are promising candidates for vaginal microbicide development. Their structural variance and accompanying mechanistic diversity provide a wide range of inhibitors whose antiviral activity can be exerted at nearly every stage of the HIV lifecycle. Additionally, peptide modification has been explored as a method for improving the anti-HIV activity of host defense peptides. Structure- and sequence-based alterations have achieved varying success in improving the potency and specificity of anti-HIV peptides. Overall, peptides have been discovered or engineered to inhibit HIV with therapeutic indices of >1000, encouraging their advancement toward clinical trials. Here we review the naturally occurring anti-HIV host defense peptides, demonstrating their breadth of mechanistic diversity, and exploring approaches to enhance and optimize their activity in order to expedite their development as safe and effective anti-HIV vaginal microbicides. PMID:22264047

  4. Survival in cats with naturally occurring chronic kidney disease (2000-2002).

    PubMed

    Boyd, L M; Langston, C; Thompson, K; Zivin, K; Imanishi, M

    2008-01-01

    Duration of survival of cats with naturally occurring chronic kidney disease (CKD) is poorly characterized. Stage of kidney disease based on serum creatinine concentration (SCr) at the time of diagnosis and after correction of prerenal azotemia is strongly associated with duration of survival in cats. Two hundred and eleven client-owned cats with naturally occurring CKD evaluated between April 2000 and January 2002. Retrospective case review of 733 cats with SCr > 2.3 mg/dL. Examination of the medical records identified 211 cats that met all other inclusion and exclusion criteria for this study. Clinical characteristics, clinicopathologic data, and survival times were extracted from the medical record. Owners and referring veterinarians were contacted by phone to obtain follow-up if it was not documented in the record. Kaplan-Meier survival curves were performed to determine survival times for International Renal Interest Society (IRIS) stage both at diagnosis and at baseline (ie, after correction of prerenal azotemia). Median survival for cats in IRIS stage IIb at the time of diagnosis was 1,151 days (range 2-3,107), and was longer than survival in stage III (median 778, range 22-2,100) or stage IV (median 103, range 1-1,920) (P-value< .0001). P-value for effect of stage at diagnosis was < .0001. IRIS stage of CKD based on serum creatinine at the time of diagnosis is strongly predictive of survival in cats with naturally occurring CKD.

  5. Contribution of synthetic and naturally occurring organobromine compounds to bromine mass in marine organisms.

    PubMed

    Wan, Yi; Jones, Paul D; Wiseman, Steve; Chang, Hong; Chorney, Dave; Kannan, Kurunthachalam; Zhang, Kun; Hu, Jian-Ying; Khim, Jong Seong; Tanabe, Shinsuke; Lam, Michael H W; Giesy, John P

    2010-08-15

    An extraction, separation, and purification method was developed for the identification and quantification of total bromine (TBr), extractable organobromine (EOBr), and five classes of identified EOBrs. Instrumental neutron activation analysis (INAA) was utilized to quantify EOBr and TBr. The method was then applied to liver samples of tuna, albatross, and polar bear collected from remote marine locations. Polybrominated biphenyls (PBBs), polybrominated diphenyl ethers (PBDEs), bromophenols (BRPs), hydroxylated (OH-) and methoxylated (MeO-) PBDEs were analyzed as identified EOBr. The majority of the bromine in these marine organisms was nonextractable or inorganic, with EOBr accounting for 10-28% of the TBr. Of the identified EOBr, in tuna and albatross, naturally occurring compounds, including MeO-PBDEs, OH-PBDEs, and BPRs, were prevalent. However, the identifiable EOBr in polar bears consisted primarily of synthetic compounds, including PBDEs and PBBs. Overall, 0.08-0.11% and 0.008-0.012% of EOBr and TBr, respectively, were identified. The proportion of EOBr that was identified in marine organisms was relatively small compared to the proportions for organofluorine and organochlorine compounds. This could be related to the great diversity of naturally occurring organobromine compounds in the environment. Naturally occurring brominated fatty acids were estimated to be the predominant compounds in the EOBr fraction.

  6. Finding the traces of behavioral and cognitive processes in big data and naturally occurring datasets.

    PubMed

    Paxton, Alexandra; Griffiths, Thomas L

    2017-04-19

    Today, people generate and store more data than ever before as they interact with both real and virtual environments. These digital traces of behavior and cognition offer cognitive scientists and psychologists an unprecedented opportunity to test theories outside the laboratory. Despite general excitement about big data and naturally occurring datasets among researchers, three "gaps" stand in the way of their wider adoption in theory-driven research: the imagination gap, the skills gap, and the culture gap. We outline an approach to bridging these three gaps while respecting our responsibilities to the public as participants in and consumers of the resulting research. To that end, we introduce Data on the Mind ( http://www.dataonthemind.org ), a community-focused initiative aimed at meeting the unprecedented challenges and opportunities of theory-driven research with big data and naturally occurring datasets. We argue that big data and naturally occurring datasets are most powerfully used to supplement-not supplant-traditional experimental paradigms in order to understand human behavior and cognition, and we highlight emerging ethical issues related to the collection, sharing, and use of these powerful datasets.

  7. California Dept. of Toxic Substances Control (DTSC) Update of the Schools Naturally Occurring Asbestos Guidance

    NASA Astrophysics Data System (ADS)

    Malinowski, M.

    2012-12-01

    Prior to acquisition and/or construction of prospective school sites, the California Education Code mandates that school districts complete environmental assessments and cleanups for prospective new or expanding school sites in order to qualify for state funding. If prospective school sites are determined to have environmental contamination from hazardous materials, including naturally occurring hazardous materials such as naturally occurring asbestos (NOA), where there may be unacceptable potential health risks, the school sites must be properly mitigated prior to occupancy for protection of human health and the environment. NOA is of special concern for schools, because children who are exposed to asbestos may be at increased risk of developing asbestos-related diseases over time. In order to protect human health, the Department of Toxic Substances Control's (DTSC) goals at school sites are to: 1) identify the presence of NOA in school site soils using exposure-reducing soil thresholds; 2) manage potential NOA exposures using mitigation measures to reduce generation of airborne asbestos fibers from soils on school sites; and 3) ensure long-term monitoring and protection of mitigation measures via Operations & Maintenance activities. DTSC is currently in the process of revising its Interim Guidance Naturally Occurring Asbestos (NOA) at School Sites - September 2004. The revisions include: 1) updating the guidance to consider incremental sampling for use at NOA sites in consultation with DTSC's project manager and technical staff, and 2) documenting a tiered approach to addressing high and low activity areas on a school.

  8. Factors Affecting Comparative Resistance of Naturally Occurring and Subcultured Pseudomonas aeruginosa to Disinfectants

    PubMed Central

    Carson, L. A.; Favero, M. S.; Bond, W. W.; Petersen, N. J.

    1972-01-01

    A strain of Pseudomonas aeruginosa was isolated in pure culture from the reservoir of a hospital mist therapy unit by an extinction-dilution technique; its natural distilled water environment was used as a growth and maintenance medium. After a single subculture on Trypticase soy agar, the strain showed a marked decrease in resistance to inactivation by acetic acid, glutaraldehyde, chlorine dioxide, and a quaternary ammonium compound when compared with naturally occurring cells grown in mist therapy unit water. The following factors were observed to affect the relative resistances of naturally occurring and subcultured cells of the P. aeruginosa strain: (i) temperature at which the cultures were incubated prior to exposure to disinfectants, (ii) growth phase of the cultures at the time of exposure to disinfectants, (iii) nature of the suspending menstruum for disinfectants, and (iv) exposure to fluorescent light during incubation of inocula prior to testing. The applied significance of these findings may alter the present concepts of disinfectant testing as well as routine control procedures in the hospital environment. PMID:4624209

  9. Serum canine pancreatic lipase immunoreactivity in experimentally induced and naturally occurring canine monocytic ehrlichiosis (Ehrlichia canis).

    PubMed

    Mylonakis, Mathios E; Xenoulis, Panagiotis G; Theodorou, Konstantina; Siarkou, Victoria I; Steiner, Jörg M; Harrus, Shimon; Leontides, Leonidas; Rallis, Timoleon; Suchodolski, Jan S; Koutinas, Christos K; Koutinas, Alexander F

    2014-03-14

    Ehrlichia canis infection causes multisystemic disease in dogs (canine monocytic ehrlichiosis, CME) which is associated with variable morbidity and mortality. Atypical clinical manifestations, including gastrointestinal signs, may occasionally occur in CME and approximately 10-15% of dogs are presented with historical or clinical evidence of vomiting, diarrhea, and/or abdominal discomfort. The objective of this study was to investigate if there are any alterations in serum canine pancreatic lipase immunoreactivity (cPLI) in dogs with experimentally induced or naturally occurring monocytic ehrlichiosis. Serum samples from 10 Beagle dogs experimentally infected with E. canis and two healthy uninfected Beagles were serially examined; samples from 20 naturally infected dogs (10 with non-myelosuppressive [NME] and 10 with myelosuppressive [ME] ehrlichiosis) were also examined at a given point in time (cross-sectional sampling). None of the experimentally infected Beagles showed gastrointestinal signs or increased cPLI concentrations prior to or following the artificial infection. Three naturally infected dogs with NME and one with ME demonstrated serum cPLI concentrations in the diagnostic range for pancreatitis (>400 μg/L) without showing gastrointestinal signs. The results of the present study indicated that 4/20 (20%) of dogs naturally infected with E. canis demonstrated increased serum cPLI concentrations consistent with mild and clinically inapparent pancreatitis.

  10. The evolution of standards for naturally occurring fluorides: an example of scientific due process.

    PubMed Central

    Clark, N; Corbin, S

    1983-01-01

    In three quarters of a century of observation and research, the effects of fluoride on dental caries and on general bodily health have been well documented. An expanding data base has allowed a firming up of the guidance and standards for appropriate and safe levels of naturally occurring fluorides for human consumption. Over time, through specific recommendations, the maximum fluoride concentrations deemed appropriate have been altered, but by a process of considered adjustment. Although the Public Health Service has been responsible for the formalization of many of the recommended standards, those recommendations have been based on research from many fronts. In the most recent reconsideration of the standards for natural fluoride, the most exhaustive and thoroughly documented review to date was done, incorporating review by representatives from State, Federal, and private programs. Although the specific example of the development of standards for natural fluoride is used, it should be illustrative of similar processes that are constantly underway in regard to substances and factors with a potential impact on the public's health. Expansion of the data base through research and scientific inquiry will lay the foundation for future reconsideration of the standards for naturally occurring fluorides. PMID:6828638

  11. Intraspecific variation in testis asymmetry in birds: evidence for naturally occurring compensation

    PubMed Central

    Calhim, Sara; Birkhead, Tim R.

    2009-01-01

    In many taxa, the left and right testes often differ in size. The compensation hypothesis states that one testis of the pair serves as a ‘back-up’ for any reduced function in the other and provides a mechanism to explain intraspecific variation in degree and direction of gonad asymmetry. Although testis asymmetry is common in birds, evidence for natural testis compensation is unknown. Using a novel quantitative approach that can be applied to any bilateral organ or structure, we show that testis compensation occurs naturally in birds and can be complete when one testis fails to develop. Owing to a recurrent risk of testis impairment and an evolutionary trade-off between natural and sexual selections acting on the arrangement of internal organs in species with abdominal and/or seasonal testes, compensation adds an important, but neglected, dimension to measures of male reproductive investment. PMID:19324740

  12. Variation of natural radionuclides in non-ferrous fayalite slags during a one-month production period.

    PubMed

    Croymans, Tom; Vandael Schreurs, Indy; Hult, Mikael; Marissens, Gerd; Lutter, Guillaume; Stroh, Heiko; Schreurs, Sonja; Schroeyers, Wouter

    2017-03-18

    The European Basic Safety Standards (EU-BSS) describes a set of NORM (Naturally Occurring Radioactive Material)-processing industries which produce residues known to be possibly enriched in NORs (Naturally Occurring Radionuclides). These residues can be used as a component in building materials aimed for public usage. The industrial processes, in which the residues are produced, are often complex and total monitoring can be challenging especially when the origin of the used raw materials varies. In this study the NORs present in non-ferrous fayalite slags of a secondary smelter facility, a NORM-processing industry according to the EU-BSS, were monitored daily during a one-month production period. In addition flue dust samples and feedstock samples, known to contain elevated levels of NORs, of the same period were measured. The survey involved the gamma-ray spectrometric analysis of the decay products from the (238)U and (232)Th decay chains, (235)U and (40)K using HPGe detectors. Secular equilibrium was observed for the slags, flue dust and feedstock samples in the (232)Th decay chain, in contrast to the (238)U decay chain. During the month in question the ratios of maximum over minimum activity concentration were 3.1 ± 0.5 for (40)K, 4 ± 1 for (238)U, 6 ± 1 for (226)Ra, 13 ± 7 for (210)Pb, 4.5 ± 0.6 for (228)Ra and 4.7 ± 0.7 for (228)Th for the slags. Even with the activity concentration of the feedstock material ranging up to 2.1 ± 0.3 kBq/kg for (238)U, 1.6 ± 0.2 kBq for (226)Ra, 22 ± 7 kBq/kg for (210)Pb, 2.1 ± 0.2 kBq/kg for (228)Ra and 2.0 ± 0.4 kBq/kg for (228)Th, none of the slag samples exceeded the exemption/clearance levels of the EU-BSS and RP-122 part II, which can respectively provide guidance under equilibrium and in absence of equilibrium. As each NORM-processing industry has its own complexity and variability, the observed variations point out that one should approach one-time measurements or low frequency

  13. Ocean disposal option for bulk wastes containing naturally occurring radionuclides: an assessment case history. [From Niagara Falls storage site

    SciTech Connect

    Stull, E.A.; Merry-Libby, P.

    1985-01-01

    There are 180,000 m/sup 3/ of slightly contaminated radioactive wastes (36 pCi/g radium-226) currently stored at the US Department of Energy's Niagara Falls Storage Site (NFSS), near Lewiston, New York. These wastes resulted from the cleanup of soils that were contaminated above the guidelines for unrestricted use of property. An alternative to long-term management of these wastes on land is dispersal in the ocean. A scenario for ocean disposal is present

  14. Activity, specificity, and titer of naturally occurring canine anti-DEA 7 antibodies.

    PubMed

    Spada, Eva; Proverbio, Daniela; Baggiani, Luciana; Canzi, Ilaria; Perego, Roberta

    2016-11-01

    The reported prevalence of naturally occurring anti-dog erythrocyte antigen (DEA) 7 antibodies in DEA 7-negative dogs is as high as 50%. Characterization of these antibodies may better define their importance in canine transfusion medicine. We determined in vitro activity, specificity, and titer of anti-DEA 7 antibodies in DEA 7-negative dogs. Plasma samples from 317 DEA 7-negative dogs were cross-matched with DEA 7-positive red blood cells (RBCs) using gel column technology. Agglutination occurred with DEA 7-positive RBCs but not with DEA 7-negative RBCs in 73 samples (23%), which were hence classified as containing anti-DEA 7 antibodies. These samples were evaluated for hemolytic and agglutinating activity, strength of agglutination, and antibody specificity and titers. All samples showed agglutination but none showed hemolysis. Gel agglutination was graded as 1+ for 20 samples (27%), 2+ for 49 samples (67%), 3+ for 4 samples (6%); no samples were graded 4+. The agglutination titer was <1:2 for 51 samples (73%), 1:2 for 13 samples (19%), 1:4 for 4 samples (5%), and 1:8 for 2 samples (3%). Of 16 samples treated with 2-mercaptoethanol, 11 samples (69%) contained only IgM, 4 samples (25%) exhibited only IgG activity, and 1 sample (6%) had both IgG and IgM activity. Low titers of warm, weakly agglutinating, mostly naturally occurring IgM anti-DEA 7 antibodies were found in 23% of DEA 7-negative dogs. The presence of naturally occurring anti-DEA 7 antibodies suggests that cross-matching of canine blood recipients is advisable, even at first transfusion, to minimize delayed transfusion reactions.

  15. Quantitative and qualitative leukocyte abnormalities in dogs with experimental and naturally occurring acute canine monocytic ehrlichiosis.

    PubMed

    Gianopoulos, Athena; Mylonakis, Mathios E; Theodorou, Konstantina; Christopher, Mary M

    2016-06-01

    Canine monocytic ehrlichiosis (CME) is one of the most important tick-borne diseases worldwide. Cytopenias have been observed in both acute (nonmyelosuppressive) and chronic (myelosuppressive) CME; however, leukocyte abnormalities and indices have been incompletely described in dogs with acute CME. The aims of this study were to analyze temporal changes in differential leukocyte counts, leukocyte morphology, myeloperoxidase index (MPXI), and lobularity index (LI) in dogs with experimental and naturally occurring acute CME. Differential leukocyte counts and morphology were evaluated in archived blood smears from 13 Beagle dogs experimentally infected with Ehrlichia canis and evaluated weekly for 42 days postinfection (DPI); 20 dogs with naturally occurring acute CME also were evaluated. MPXI and LI were obtained from ADVIA reports. Wilcoxon tests were used to assess changes over time; leukogram results in natural cases were assessed in comparison with reference intervals. In experimental dogs, significant decreases in neutrophil, monocyte, lymphocyte, and eosinophil counts, and a mild left shift occurred within 14 DPI. The MPXI decreased significantly between 14 and 21 DPI and remained low, while LI increased from 14 to 35 DPI. Lymphocyte counts rebounded at 21 DPI, normalizing total WBC counts. Neutrophil toxicity was seen rarely, but reactive lymphocytes were observed frequently. Dogs with natural infection had variable patterns of leukocyte changes. Acute CME is associated with several discrete quantitative and qualitative leukogram changes indicative of concurrent inflammation, antigenic stimulation, and stress. Changes in MPXI and LI warrant further investigation in dogs with CME and other diseases. © 2016 American Society for Veterinary Clinical Pathology.

  16. IMAGE Observations of Sounder Stimulated and Naturally Occurring Fast Z mode Cavity Noise

    NASA Astrophysics Data System (ADS)

    Sonwalkar, V. S.; Taylor, C.; Reddy, A.

    2015-12-01

    We report first observations of sounder stimulated and naturally occurring fast Z mode (ZM) cavity noise detected by the Radio Plasma Imager (RPI) on the IMAGE satellite. The fast Z mode cavity noise is a banded, structure-less radio emission trapped inside fast Z mode cavities, which are characterized by a minimum (fz,min) in fast Z mode cut-off frequency (fz) along a geomagnetic field line [Gurnett et al., JGR, 1983]. Fast Z mode waves reflect at fz ~ f, where f is the wave frequency. Waves in the frequency range fz,min < f < fz,max, where fz,max is the maximum fz above fz,min altitude, are trapped within the cavity as they bounce back and forth between reflection altitudes (fz ~ f) above and below the fz,min altitude. These trapped waves will be observed by a satellite passing through the cavity. The observed cavity noise lower cutoff is at the local Z mode cut-off frequency (fz,Sat) and the upper cut-off is presumably close to fz,max. The cavity noise is observed typically inside the plasmasphere. Comparison of cavity noise as observed on the plasmagram obtained during active sounding with that observed on the dynamic spectra obtained from the interspersed passive wave measurements indicate that the cavity noise is either stimulated by transmissions from the sounder (RPI) or is of natural origin. The sounder stimulated noise is often accompanied by fast Z mode echoes. The naturally occurring cavity noise is observed on both the plasmagram and the dynamic spectra. We believe the stimulated cavity noise is generated due to scattering from small-scale irregularities of waves transmitted by RPI. One potential candidate for the source of naturally occurring Z mode cavity noise is the ring current electrons that can generate fast ZM waves via higher order cyclotron resonance [Nishimura et al., Earth Planets Space, 2007].

  17. Bioaccumulation of natural radionuclides in molluscs from the Ebro Delta area.

    PubMed

    Fonollosa, E; Peñalver, A; Aguilar, C; Borrull, F

    2017-01-01

    (210)Po, (210)Pb, (234)U, (238)U, (232)Th and (230)Th were analysed in the edible part of four different species of bivalves typically produced and consumed in the Ebro Delta area. The results show that the main contributor to the radioactive content in these species was (210)Po, with values ranging between 263.1 ± 26.6 and 813.0 ± 72.9 Bq/kg (d.w.), which are higher than the usual reported activity levels in other geographical areas. This can probably be attributed to the activities of a phosphate industrial plant located upstream on the Ebro River, which may lead to enhanced levels of naturally occurring radioactive isotopes in the aquatic ecosystem. To determine the possible impact on health, the committed effective doses through the consumption of the different species were evaluated and the cumulative total annual effective dose for their consumption was estimated to 187.6 μSv/year, which is in the range of 200-1000 μSv/year given by UNSCEAR.

  18. Alaska, Naturally Occurring Asbestos: Experiences, Policy and 2012 Limitation of Liability Legislation

    NASA Astrophysics Data System (ADS)

    Hargesheimer, J.; Perkins, R.

    2012-12-01

    Naturally Occurring Asbestos (NOA) occurs in mineral deposits in Alaska. There are many regions in Alaska that have minerals in surface rocks that may contain asbestos and asbestos has been discovered in many locations in Alaska. Gravel is constantly in demand for heavy construction projects, but some remote localities in Alaska do not have gravel sources that are NOA-free. Determining if NOA can be safely used in heavy construction materials and what can or should be done with NOA materials that are already in place are complex questions. Answers will depend on the amount and type of asbestos mineral, how it is handled in processing, and how it is maintained - all subject to regulation and control of operations. The State of Alaska recently enacted legislation (HB 258) providing, among other things, "… immunity for the state and for landowners, extractors, suppliers, transporters, and contractors for certain actions or claims arising in connection with the use of gravel or aggregate material containing naturally occurring asbestos in certain areas." Implementation of the law and interim regulations and guidance should enable use of NOA for heavy construction materials in Alaska, but as with any new law, it will take some time to understand its full scope and effect.

  19. Magic angle magnetic resonance imaging of diode laser induced and naturally occurring lesions in equine tendons.

    PubMed

    Spriet, Mathieu; Murphy, Brian; Vallance, Stuart A; Vidal, Martin A; Whitcomb, Mary Beth; Wisner, Erik R

    2012-01-01

    Magic angle magnetic resonance (MR) imaging consists of imaging tendons at 55° to the magnetic field. In people, magic angle MR imaging is valuable for detection of chronic tendon lesions and allows calculation of tendon T1 values. Increased T1 values occur in people with chronic tendinopathy. The T1 values of normal equine tendons have been reported but there are no available data for abnormal equine tendons. Twelve limbs were studied. Two limbs had diode laser tendon lesions induced postmortem, four limbs had diode laser tendon lesions induced in vivo and six limbs had naturally occurring tendon lesions. The limbs were imaged at 1.5 T using both conventional MR imaging and magic angle MR imaging. The post-mortem laser induced lesions were identified only with magic angle MR imaging. The in vivo induced lesions and naturally occurring lesions were identified with both techniques but had a different appearance with the two imaging techniques. Magic angle imaging was helpful at identifying lesions that were hypointense on conventional imaging. Increased T1 values were observed in all abnormal tendons and in several tendons with a subjectively normal MR appearance. The increased T1 value may reflect diffuse changes in the biochemical composition of tendons. Magic angle imaging has potential as a useful noninvasive tool to assess the changes of the extracellular tendon matrix using T1 values.

  20. Phytohormonal basis for the plant growth promoting action of naturally occurring biostimulators.

    PubMed

    Kurepin, Leonid V; Zaman, Mohammad; Pharis, Richard P

    2014-07-01

    There is increasing interest in the use of naturally occurring 'biostimulators' for enhancing the growth of agricultural and horticultural crops. Bacteria, fungi and protozoa, as well as marine algae-based seaweed extracts, can produce or contain biostimulators. The activity of biostimulators to promote plant growth is often attributed to their ability to directly or indirectly provide mineral nutrients (mostly N, but also P, S and other macro- and micro-nutrients) to plants. Alternatively, biostimulators are postulated to increase the plant's ability to assimilate these mineral nutrients, often in return for photo-assimilates (as occurs with certain bacteria and fungi associations). Although optimal growth of plants depends on the availability of adequate mineral nutritients, that growth (and also development, including reproduction) is also regulated by plant hormones (phytohormones), including gibberellins, auxins and cytokinins. This review describes and discusses the evidence that the presence or application of biostimulators also increases plant growth directly via phytohormone action and also influences the plant's ability to control its own hormone biosynthesis and homeostasis. Finally, it discusses the need for a better understanding of the role(s) that are played by the naturally occurring biostimulators associated with the plant in the crop field. It is suggested that better understanding will allow for optimal crop yield returns, since disruptions of phytohormone homeostasis in plant organs and tissues can yield either beneficial or sub-optimal outcomes.

  1. Biological activity of some naturally occurring resins, gums and pigments against in vitro LDL oxidation.

    PubMed

    Andrikopoulos, Nikolaos K; Kaliora, Andriana C; Assimopoulou, Andreana N; Papapeorgiou, Vassilios P

    2003-05-01

    Naturally occurring gums and resins with beneficial pharmaceutical and nutraceutical properties were tested for their possible protective effect against copper-induced LDL oxidation in vitro. Chiosmastic gum (CMG) (Pistacia lentiscus var. Chia resin) was the most effective in protecting human LDL from oxidation. The minimum and maximum doses for the saturation phenomena of inhibition of LDL oxidation were 2.5 mg and 50 mg CMG (75.3% and 99.9%, respectively). The methanol/water extract of CMG was the most effective compared with other solvent combinations. CMG when fractionated in order to determine a structure-activity relationship showed that the total mastic essential oil, collofonium-like residue and acidic fractions of CMG exhibited a high protective activity ranging from 65.0% to 77.8%. The other natural gums and resins (CMG resin 'liquid collection', P. terebinthus var. Chia resin, dammar resin, acacia gum, tragacanth gum, storax gum) also tested as above, showed 27.0%-78.8% of the maximum LDL protection. The other naturally occurring substances, i.e. triterpenes (amyrin, oleanolic acid, ursolic acid, lupeol, 18-a-glycyrrhetinic acid) and hydroxynaphthoquinones (naphthazarin, shikonin and alkannin) showed 53.5%-78.8% and 27.0%-64.1% LDL protective activity, respectively. The combination effects (68.7%-76.2% LDL protection) of ursolic-, oleanolic- and ursodeoxycholic- acids were almost equal to the effect (75.3%) of the CMG extract in comparable doses.

  2. Hh signaling inhibitors from Vitex negundo; naturally occurring inhibitors of the GLI1-DNA complex.

    PubMed

    Arai, Midori A; Fujimatsu, Teruhisa; Uchida, Kyoko; Sadhu, Samir K; Ahmed, Firoj; Ishibashi, Masami

    2013-05-01

    The hedgehog (Hh) signaling pathway has crucial roles in embryonic development, cell maintenance and proliferation, and is also known to contribute to cancer cell growth. New naturally occurring Hh inhibitors (1, 7 and 9) were isolated from Vitex negundo using our previously constructed cell-based assay. Bioactivity guided isolation provided 9 natural compounds including a new diterpene, nishindanol (9). Compounds 7 and 9 showed cytotoxicity against cancer cell lines in which Hh signaling was aberrantly activated. Vitetrifolin D (7; GLI1 transcriptional inhibition IC50 = 20.2 μM) showed inhibition of Hh related protein (PTCH and BCL2) production. Interestingly, the constructed electrophoresis mobility shift assay revealed that vitetrifolin D (7) disrupted GLI1 binding on its DNA binding domain. epi-Sclareol (8; inactive), possessing a similar structure to 7, did not show inhibition of GLI1–DNA complex formation. This is the first example of naturally occurring inhibitors of GLI1–DNA complex formation.

  3. Naturally Occurring Surface Antigen Variants of Hepatitis B Virus in Tunisian Patients.

    PubMed

    Chaouch, Houda; Taffon, Stefania; Villano, Umbertina; Equestre, Michele; Bruni, Roberto; Belhadj, Manel; Hannachi, Naila; Aouni, Mahjoub; Letaief, Amel; Ciccaglione, Anna Rita

    2016-01-01

    In Tunisia, the prevalence of naturally occurring surface (S) gene variants of hepatitis B virus (HBV) has not been determined. In the present study, the prevalence of these variants was examined in terms of the clinical and viral state in a series of 99 Tunisian patients with HBV infection. The S genes were amplified and directly sequenced. Genotype D was predominant (98%), 40.4% isolates belonged to subgenotypes D7 and 1 to subgenotype D2. The most common subtype was ayw2 (95.9%). In total, 60.6% of the studied strains harbored S mutations. Several novel mutation patterns were detected. Interestingly, the presence of S mutations was significantly correlated with the D7 subgenotype, low HBV DNA and advancing age (≥35 years), and tended to be higher in liver cirrhosis than in chronic infection. The global prevalence of the major hydrophilic region variants was 12.1%, with substitution S143L/T as the most frequent (4%). Only 33.9% of S substitutions produced amino acid changes in the polymerase gene. In conclusion, a high prevalence of naturally occurring HBsAg variants was observed among Tunisian HBV carriers. Natural viral variability in a geographical region and duration of infection are among the major factors associated with the occurrence of S mutations.

  4. Naturally occurring arsenic in the groundwater at the Kansas City Plant

    SciTech Connect

    Korte, N.E.

    1990-12-01

    This report describes an investigation concerning the presence of arsenic in concentrations exceeding 0.4 mg/L in the groundwater under the Department of Energy's Kansas City Plant (KCP). The study consisted of four distinct phases: a thorough review of the technical literature, a historical survey of arsenic use at the facility, a laboratory study of existing techniques for determining arsenic speciation, and a field program including water, soil, and sediment sampling. The historical survey and literature review demonstrated that plant activities had not released significant quantities of arsenic to the environment but that similar occurrences of arsenic in alluvial groundwater are widespread in the midwestern United States. Laboratory studies showed that a chromatographic separation technique was necessary to accurately determine arsenic speciation for the KCP groundwater samples. Field studies revealed that naturally occurring reducing conditions prevalent in the subsurface are responsible for dissolving arsenic previously sorbed by iron oxides. Indeed, the data demonstrated that the bulk arsenic concentration of site subsoils and sediments is {approximately}7 mg/kg, whereas the arsenic content of iron oxide subsamples is as high as 84 mg/kg. Literature showed that similar concentrations of arsenic in sediments occur naturally and are capable of producing the levels of arsenic found in groundwater monitoring wells at the KCP. The study concludes, therefore, that the arsenic present in the KCP groundwater is the result of natural phenomena. 44 refs., 8 figs., 14 tabs.

  5. The enrichment of natural radionuclides in oil shale-fired power plants in Estonia--the impact of new circulating fluidized bed technology.

    PubMed

    Vaasma, Taavi; Kiisk, Madis; Meriste, Tõnis; Tkaczyk, Alan Henry

    2014-03-01

    Burning oil shale to produce electricity has a dominant position in Estonia's energy sector. Around 90% of the overall electric energy production originates from the Narva Power Plants. The technology in use has been significantly renovated - two older types of pulverized fuel burning (PF) energy production units were replaced with new circulating fluidized bed (CFB) technology. Additional filter systems have been added to PF boilers to reduce emissions. Oil shale contains various amounts of natural radionuclides. These radionuclides concentrate and become enriched in different boiler ash fractions. More volatile isotopes will be partially emitted to the atmosphere via flue gases and fly ash. To our knowledge, there has been no previous study for CFB boiler systems on natural radionuclide enrichment and their atmospheric emissions. Ash samples were collected from Eesti Power Plant's CFB boiler. These samples were processed and analyzed with gamma spectrometry. Activity concentrations (Bq/kg) and enrichment factors were calculated for the (238)U ((238)U, (226)Ra, (210)Pb) and (232)Th ((232)Th, (228)Ra) family radionuclides and for (40)K in different CFB boiler ash fractions. Results from the CFB boiler ash sample analysis showed an increase in the activity concentrations and enrichment factors (up to 4.5) from the furnace toward the electrostatic precipitator block. The volatile radionuclide ((210)Pb and (40)K) activity concentrations in CFB boilers were evenly distributed in finer ash fractions. Activity balance calculations showed discrepancies between input (via oil shale) and output (via ash fractions) activities for some radionuclides ((238)U, (226)Ra, (210)Pb). This refers to a situation where the missing part of the activity (around 20% for these radionuclides) is emitted to the atmosphere. Also different behavior patterns were detected for the two Ra isotopes, (226)Ra and (228)Ra. A part of (226)Ra input activity, unlike (228)Ra, was undetectable in the

  6. Heteroaggregation of multiwall Carbon Nanotubes and Naturally Occurring Colloids in Aquatic Systems

    NASA Astrophysics Data System (ADS)

    Coogan, Patricia

    The heteroaggregation of engineered nanoparticles (ENPs) with naturally occurring colloids (NOCs) plays an important role in determining the ultimate fate and transport of nanomaterials in the environment. The objective of this research was to characterize the potential for heteroaggregation between functionalized multiwall carbon nanotubes (MWCNTs) with NOCs in the aquatic environment. Carboxylated MWCNTs (COOH-MWCNTs) and amine functionalized MWCNTs (NH2-MWCNTs) were studied. The natural clay kaolinite was chosen as a model NOC due to its widespread presence in the natural environment and unique charge heterogeneity. In this study, the aggregation between CNTs and kaolinite was analyzed for a range of CNT:NOC ratios and pH as well as in different source waters in a series of sedimentation and aggregation experiments. Sedimentation was monitored using ultraviolet-visible (UV-VIS) spectroscopy, while aggregation was characterized by dynamic light scattering. The heteroaggregation of the COOH-MWCNTs was found to be heavily dependent on pH and the CNT:NOC ratio. The sedimentation rate of the CNT-NOC mixture indicated by UV-VIS spectroscopy and average particle size measured by DLS both increased at low pH while the CNT solution remained stable over time when tested at the same solution chemistry. As the CNT:NOC ratio decreased, the CNT-NOC mixture demonstrated enhanced sedimentation behavior at pH 3. The enhanced sedimentation coupled with increasing particle size of the mixture indicated the presence of CNT-NOC heteroaggregates. At higher pH, no enhanced sedimentation occurred for the range of ratios tested. The NH2-MWCNTs were not dispersible at neutral pH were therefore only tested at pH 3. All solutions regardless of ratio indicated no significant evidence of enhanced sedimentation due to heteroaggregation for the NH 2-MWCNTs in this study. Filtered and unfiltered natural water samples from Lake Houston and the Trinity River were also analyzed and found to

  7. Assessing Natural Radionuclide Migration in the Legacy Tailings of Uranium Production

    NASA Astrophysics Data System (ADS)

    Bondarenko, G.; Koliabina, I.; Marinich, O.

    2011-12-01

    The former Prydniprovsky Chemical Plant in Dniprodzerzhynsk, Ukraine, processed uranium ore from 1949 until 1991. Multiple tailing ponds containing solid residual waste products from the uranium leaching and processing of uranium were accumulated along the Dnieper River, including the largest, adjacent to the Dnieper Reservoir, containing over 12 million tons of tailings. Samples for this study were selected from a core recovered from the Dnieper tailing pit in 2009, and used to assess radionuclide migration from tailing ponds. Samples were selected from different depths of the tailing pit core, analyzed for total radionuclide concentrations [Marinich et al., 2009], and successively leached using distilled water, followed by 1N ammonium acetate solution, and finally by 1N HCl solution. Leaching times were ~24 h at 15.17 °C. 238U, 230Th and 226Ra leachate activities were measured by γ-spectrometry with a Ge(Li) detector. 210Pb activity was measured using a SEB-01 scintillation β-spectrometer. Errors depended on measuring method, radionuclide, activity and exposure time: 238U, 11.9%; 230Th, 10.9%; 226Ra, 9.3%; 210Pb ~30%. The average total 238U activity in the tailing profile was 4 Bq/g. The concentration of 238U in the water leachates increased with depth from 14.5% (7-7.5 m), to 43% (11-11.5 m). The concentration of 238U in the acid leachates behaved similarly, increasing from 5.5 % to 15.5% with depth. While the total 230Th activity in increased from 30 Bq/g (7-7.5 m) to 540 Bq/g (11-11.5 m), the 230Th concentration in ammonium acetate leachates decreased from ˜15% to ˜1%. The concentration of 226Ra in all leachates was <1%, indicating that, under conditions of the Dnieper tailing pit, 226Ra is essentially immobile. The concentration of 210Pb in the leachates was as high as 10%. In general, the magnitude of mobile activity from the Dnieper tailing pit core samples decreases in the order 238U>230Th≥210Pb> 226Ra. Secular radioactive equilibrium in the 238U

  8. Articular Osteochondrosis: A Comparison of Naturally-Occurring Human and Animal Disease

    PubMed Central

    McCoy, Annette M; Toth, Ferenc; Dolvik, Nils I; Ekman, Stina; Ellermann, Jutta; Olstad, Kristin; Ytrehus, Bjornar; Carlson, Cathy S

    2013-01-01

    Background Osteochondrosis (OC) is a common developmental orthopedic disease affecting both humans and animals. Despite increasing recognition of this disease among children and adolescents, its pathogenesis is incompletely understood because clinical signs are often not apparent until lesions have progressed to end-stage, and examination of cadaveric early lesions is not feasible. In contrast, both naturally-occurring and surgically-induced animal models of disease have been extensively studied, most notably in horses and swine, species in which OC is recognized to have profound health and economic implications. The potential for a translational model of human OC has not been recognized in the existing human literature. Objective The purpose of this review is to highlight the similarities in signalment, predilection sites and clinical presentation of naturally-occurring OC in humans and animals and to propose a common pathogenesis for this condition across species. Study Design Review Methods The published human and veterinary literature for the various manifestations of OC was reviewed. Peer-reviewed original scientific articles and species-specific review articles accessible in PubMed (US National Library of Medicine) were eligible for inclusion. Results A broad range of similarities exists between OC affecting humans and animals, including predilection sites, clinical presentation, radiographic/MRI changes, and histological appearance of the end stage lesion, suggesting a shared pathogenesis across species. Conclusion This proposed shared pathogenesis for OC between species implies that naturally-occurring and surgically-induced models of OC in animals may be useful in determining risk factors and for testing new diagnostic and therapeutic interventions that can be used in humans. PMID:23954774

  9. Comparison of Thoracic Radiography and Computed Tomography in Calves with Naturally Occurring Respiratory Disease.

    PubMed

    Fowler, Jennifer; Stieger-Vanegas, Susanne M; Vanegas, Jorge A; Bobe, Gerd; Poulsen, Keith P

    2017-01-01

    To evaluate the severity and extent of lung disease using thoracic computed radiography (CR) compared to contrast-enhanced multi-detector computed tomography (MDCT) of the thorax in calves with naturally occurring respiratory disease and to evaluate the feasibility and safety of performing contrast-enhanced thoracic multi-detector MDCT examinations in sedated calves. Furthermore, to evaluate if combining CR or MDCT with respiratory scoring factors will improve prediction of the chronicity of pulmonary disease in calves. Thirty Jersey heifer calves ranging in age between 25 and 89 days with naturally occurring respiratory disease. All calves were evaluated via thoracic CR and contrast-enhanced MDCT. All calves were euthanized immediately following thoracic MDCT and submitted for necropsy. Imaging and histopathology results were compared with each other. Thoracic MDCT was superior for evaluation of pneumonia in calves due to the lack of summation in all areas of the lungs. Intravenously administered sedation provided an adequate plane of sedation for acquiring MDCT images of diagnostic quality, without the need for re-scanning. A diagnosis of pneumonia was made with equal rate on both thoracic CR and MDCT. Although mild differences in classification of lung pattern and extent of lung disease were seen when comparing an experienced and a less experienced evaluator, the overall differences were not statistically significant. The best intra- and inter-observer agreement was noted when evaluating the cranioventral aspects of the lungs in either modality. Clinical respiratory scoring is inadequate for diagnosing chronicity of pneumonia in calves with naturally occurring pneumonia. Both imaging modalities allowed diagnosis of pneumonia in calves. The cranial ventral aspects of the lungs were most commonly affected. Thoracic CR and MDCT provided similar diagnostic effectiveness in diagnosing pneumonia. However, MDCT provided better assessment of subtle details, which may

  10. Interaction of flavonoids, the naturally occurring antioxidants with different media: a UV-visible spectroscopic study.

    PubMed

    Naseem, Bushra; Shah, S W H; Hasan, Aurangzeb; Sakhawat Shah, S

    2010-04-01

    Quantitative parameters for interaction of flavonoids-the naturally occurring antioxidants, with solvents and surfactants are determined using UV-visible absorption spectroscopy. The availability of flavonoids; kaempferol, apigenin, kaempferide and rhamnetin in micelles of sodium dodecyl sulfate (SDS) is reflected in terms of partition coefficient, K(c). Thermodynamic calculations show that the process of transfer of flavonoid molecules to anionic micelles of SDS is energy efficient. A distortion in flavonoid's morphology occurs in case of kaempferol and apigenin in surfactant and water, exhibited in terms of a new band in the UV region of electronic spectra of these flavonoids. The partition coefficients of structurally related flavonoids are correlated with their antioxidant activities. Copyright 2010 Elsevier B.V. All rights reserved.

  11. Polymer prodrug nanoparticles based on naturally occurring isoprenoid for anticancer therapy.

    PubMed

    Trung Bui, Duc; Maksimenko, Andrei; Desmaële, Didier; Harrisson, Simon; Vauthier, Christine; Couvreur, Patrick; Nicolas, Julien

    2013-08-12

    The synthesis of a novel class of polymer prodrug nanoparticles with anticancer activity is reported by using squalene, a naturally occurring isoprenoid, as a building block by the reversible addition-fragmentation (RAFT) technique. The RAFT agent was functionalized by gemcitabine (Gem) as anticancer drug, and the polymerization of squalenyl-methacrylate (SqMA) led to well-defined macromolecular prodrugs comprising one Gem at the extremity of each polymer chain. The amphiphilic nature of the resulting Gem-PSqMA conjugates allowed them to self-assemble into long-term stable and narrowly dispersed nanoparticles with significant anticancer activity in vitro on various cancer cell lines. To confer stealth properties on these nanoparticles, their PEGylation was successfully performed, as confirmed by X-ray photoelectron spectroscopy (XPS) and complement activation assay. It was also shown that the PEGylated nanoparticles could be internalized in cancer cells to a greater extent than their non-PEGylated counterparts.

  12. Bibliography of reports, papers, and presentations on naturally occurring radioactive material (NORM) in petroleum industry wastes

    SciTech Connect

    Smith, K.P.; Wilkey, M.L.; Hames, R.D.

    1997-07-01

    This bibliography was created to support projects conducted by Argonne National Laboratory (ANL) addressing issues related to naturally occurring radioactive material (NORM) in petroleum industry wastes. The bibliography provides citations for many of the available published reports, papers, articles, and presentations on petroleum industry NORM. In the past few years, the rapid expansion of NORM treatment and disposal technologies, the efforts to characterize NORM wastes and their associated potential risks, and the promulgation of state-level NORM regulatory programs have been well-documented in project reports and in papers presented at technical conferences and symposia. There are 221 citations.

  13. Naturally occurring bioactive Cyclobutane-containing (CBC) alkaloids in fungi, fungal endophytes, and plants.

    PubMed

    Dembitsky, Valery M

    2014-10-15

    This article focuses on the occurrence and biological activities of cyclobutane-containing (CBC) alkaloids obtained from fungi, fungal endophytes, and plants. Naturally occurring CBC alkaloids are of particular interest because many of these compounds display important biological activities and possess antitumour, antibacterial, antimicrobial, antifungal, and immunosuppressive properties. Therefore, these compounds are of great interest in the fields of medicine, pharmacology, medicinal chemistry, and the pharmaceutical industry. Fermentation and production of CBC alkaloids by fungi and/or fungal endophytes is also discussed. This review presents the structures and describes the activities of 98 CBC alkaloids.

  14. The new IAEA reference material: IAEA-434 technologically enhanced naturally occurring radioactive materials (TENORM) in phosphogypsum.

    PubMed

    Shakhashiro, A; Sansone, U; Wershofen, H; Bollhöfer, A; Kim, C K; Kim, C S; Kis-Benedek, G; Korun, M; Moune, M; Lee, S H; Tarjan, S; Al-Masri, M S

    2011-01-01

    A reliable determination of Technologically Enhanced Naturally Occurring Radioactive Materials in phosphogypsum is necessary to comply with radiation protection and environmental regulations. In this respect, a new phosphogypsum reference material was produced and certified to assist in the validation of analytical methods and the quality assurance of produced analytical results. This paper presents the sample preparation methodology, material homogeneity assessment, characterization campaign results and assignment of property values, and associated uncertainties. The reference values and associated uncertainties for Pb-210, Ra-226, Th-230, U-234 and U-238 were established based on consensus values calculated from analytical results reported by three National Metrology Institutes and five expert laboratories.

  15. Towards the elusive structure of kotalanol, a naturally occurring glucosidase inhibitor.

    PubMed

    Mohan, Sankar; Pinto, B Mario

    2010-04-01

    This Highlight describes the detailed approach used to determine the absolute stereochemistry of the stereogenic centers in the acyclic side chain of kotalanol, a naturally occurring glucosidase inhibitor isolated from the plant Salacia reticulata. The plant extract itself is used in Ayurvedic medicine for the treatment of Type 2 diabetes. We highlight the syntheses of proposed candidates based on structure-activity relationships, the total synthesis of kotalanol, and crystallographic studies of kotalanol and its de-O-sulfonated derivative complexed with recombinant human maltase glucoamylase (MGA), a critical intestinal glucosidase involved in the breakdown of glucose oligomers into glucose.

  16. Leishmanicidal and cytotoxic activities of extracts and naturally-occurring compounds from two Lauraceae species.

    PubMed

    Sánchez-Suárez, Jeysson; Coy-Barrera, Ericsson; Cuca, Luis Enrique; Delgado, Gabriela

    2011-02-01

    The in vitro leishmanicidal effects of ethanolic extracts and fifteen naturally-occurring compounds (five lignans, eight neolignans, a diterpene and a dihydrochalcone), obtained from Pleurothyrium cinereum and Ocotea macrophylla, were evaluated on promastigotes of Leishmania panamensis and L. braziliensis. In addition, in order to determine the selective action on Leishmania species as a safety principle, in vitro cytotoxicity on J774 cells was also evaluated for test compounds and extracts. One extract and seven compounds showed activity against Leishmania parasites at different levels. Dihydroflavokawin B (8) was found to be the most potent antileishmanial compound on both parasites, whilst (+)-otobaphenol (14), was found to be the most selective compound on L. panamensis.

  17. Naturally occurring phenanthrene degrading bacteria associated with seeds of various plant species.

    PubMed

    Fernet, Jennifer L; Lawrence, John R; Germida, James J

    2016-01-01

    Seeds of 11 of 19 plant species tested yielded naturally occurring phenanthrene degrading bacteria when placed on phenanthrene impression plates. Seed associated phenanthrene degrading bacteria were mostly detected on caragana, Canada thistle, creeping red fescue, western wheatgrass, and tall wheat grass. Based on 16S rRNA analysis the most common bacteria isolated from these seeds were strains belonging to the genera Enterobacteria, Erwinia, Burkholderia, Pantoea, Pseudomonas, and Sphingomonas. These plants may provide an excellent source of pre-adapted bacterial-plant associations highly suitable for use in remediation of contaminated soil environments.

  18. Characterization of naturally-occurring and modified fullerenes by Fourier transform mass spectrometry

    NASA Astrophysics Data System (ADS)

    Hettich, Robert L.; Jin, Changming; Compton, Robert N.; Buseck, Peter R.; Tsipursky, Semeon J.

    1993-10-01

    Fourier transform mass spectrometry (FTMS) employing both laser desorption/ionization and thermal desorption/electron ionization is useful for the detection and structural characterization of fullerenes and chemically-modified fullerenes. Examination of a carbon-rich shungite rock sample from Russia by transmission electron microscopy and FTMS provided evidence of naturally-occurring fullerenes. Ion-molecule reactions can be studied with FTMS to investigate the electron affinities of modified fullerenes. By monitoring charge exchange reactions, the electron affinities of C60Fx (x=44,46) and C70Fy (y=52,54) were found to be substantially higher than the values for the parent fullerenes.

  19. First Total Synthesis of a Naturally Occurring Iodinated 5′-Deoxyxylofuranosyl Marine Nucleoside

    PubMed Central

    Sun, Jianyun; Dou, Yanhui; Ding, Haixin; Yang, Ruchun; Sun, Qi; Xiao, Qiang

    2012-01-01

    4-Amino-7-(5′-deoxy-β-D-xylofuranosyl)-5-iodo-pyrrolo[2,3-d]pyrimidine 1, an unusual naturally occurring marine nucleoside isolated from an ascidan, Diplosoma sp., was synthesized from D-xylose in seven steps with 28% overall yield on 10 g scale. The key step was Vorbrüggen glycosylation of 5-iodo-pyrrolo[2,3-d]pyrimidine with 5-deoxy-1,2-O-diacetyl-3-O-benzoyl-D-xylofuranose. Its absolute configuration was confirmed. PMID:22690148

  20. Bay Area Air Quality Management District (BAAQMD) Naturally Occurring Asbestos Regulations and Enforcement Protocols

    NASA Astrophysics Data System (ADS)

    Wall, M.

    2012-12-01

    BAAQMD has been delegated local enforcement of the Naturally-Occurring Asbestos Airborne Toxic Control Measure for Construction, Grading, Quarrying, and Surface Mining Operations, Section 93105, Title 17, California Code of Regulation ("NOA ATCM") by the state Air Resource Board. BAAQMD will present an overview of how BAAQMD administers and enforces the NOA ATCM, as well as a discussion of various issues that have arisen at NOA projects BAAQMD has overseen, and steps that have been taken in the interest of protecting the public health.

  1. Existence of long-lived isomeric states in naturally-occurring neutron-deficient Th isotopes

    SciTech Connect

    Marinov, A.; Kashiv, Y.; Rodushkin, I.; Halicz, L.; Segal, I.; Pape, A.; Miller, H. W.; Kolb, D.; Brandt, R.

    2007-08-15

    Four long-lived neutron-deficient Th isotopes with atomic mass numbers 211 to 218 and abundances of (1-10)x10{sup -11} relative to {sup 232}Th have been found in a study of naturally-occurring Th using inductively coupled plasma-sector field mass spectrometry. It is deduced that long-lived isomeric states exist in these isotopes. The hypothesis that they might belong to a new class of long-lived high spin super- and hyperdeformed isomeric states is discussed.

  2. Naturally occurring asbestos in eastern Australia: a review of geological occurrence, disturbance and mesothelioma risk

    NASA Astrophysics Data System (ADS)

    Hendrickx, Marc

    2009-04-01

    Potential asbestos-bearing rocks account for about 0.2% of the land area of eastern Australia. The main mode of occurrence is as narrow cross fibre and slip fibre veins of chrysotile asbestos in serpentinised ophiolite complexes along the boundaries of major tectonic domains. Smaller deposits of chrysotile and amphibole asbestos occur in metamorphosed mafic and ultramafic rocks associated with the Macquarie Volcanic Arc in New South Wales. Amphibole asbestos is also known from Proterozoic and Palaeozoic amphibolite and from Devonian basalt. Natural asbestos-bearing materials in eastern Australia have been disturbed by mining, road construction, agriculture and forestry, urban development and through natural weathering processes. Persons most at risk of potential exposure to asbestos from natural sources include: farmers who work or live in areas where asbestos-bearing materials may be routinely disturbed by agricultural activities; construction workers involved in large-scale earthwork projects in areas underlain by asbestos-bearing rocks; and quarry workers who unwittingly disturb asbestos-bearing materials. Government authorities and private enterprise need to take geological factors into account to reduce the likelihood of unplanned disturbance of natural asbestos-bearing materials.

  3. Persistence of naturally occurring and genetically modified Choristoneura fumiferana nucleopolyhedroviruses in outdoor aquatic microcosms.

    PubMed

    Holmes, Stephen B; Fick, William E; Kreutzweiser, David P; Ebling, Peter M; England, Laura S; Trevors, Jack T

    2008-10-01

    To assess the persistence of genetically modified and naturally occurring baculoviruses in an aquatic environment, replicate (three) outdoor, aquatic microcosms were spiked with spruce budworm viruses [Ireland strain of Choristoneura fumiferana multiple nucleopolyhedrovirus (CfMNPV) and the recombinant CfMNPVegt(-)/lacZ(+)] at a rate of 1.86 x 10(10) occlusion bodies (OBs) m(-2) of surface area. The presence of virus in water samples collected at various times after inoculation was determined by PCR amplification of baculoviral DNA extracted from OBs. Although UV radiation rapidly degrades baculoviruses under natural conditions, both viruses persisted above the level of detection (>100 OBs 450 microL(-1) of natural pond water) for at least 1 year post-inoculation, with little difference between the viruses in their patterns of persistence. The present microcosm study suggests that occlusion bodies of baculoviruses can persist in the flocculent layer of natural ponds. On disturbance, OBs could re-enter the main water column and thus be available for transport to new locations. Implications for environmental risk assessment are discussed.

  4. Evaluation of the use of reverse osmosis to eliminate natural radionuclides from water samples.

    PubMed

    Nieto, Antonio; Palomo, Marta; Ruana, Josep; Peñalver, Alejandra; Aguilar, Carme; Borrull, Francesc

    2013-12-01

    The objective of drinking water treatment plants (DWTP) is to supply the population with tap water that is in optimal condition and in compliance with water quality regulations. In the DWTP of L'Ampolla (Tarragona, Spain), slightly high values of gross alpha activity and the amount of salts in the raw water have been observed. Conventional treatment has reduced these levels only minimally. This study tested a tertiary treatment based on reverse osmosis is tested in an industrial pilot plant (240 m3/day) The efficiency of this pilot plant to reduce the gross alpha and beta activities and the activity of some individual radioisotopes (U(238), U(234), U(235) and Ra(226)) was tested. Results showed that the elimination of alpha emitters was greater than 90%, whereas the elimination of beta emitters was about 35%. Overall, the data provided evidence that the pilot plant is effective for removing different radionuclides that can be present in the incoming water treated. Therefore, tertiary treatment based on reverse osmosis has a positive effect in water quality.

  5. Naturally Occurring Human Urinary Peptides for Use in Diagnosis of Chronic Kidney Disease*

    PubMed Central

    Good, David M.; Zürbig, Petra; Argilés, Àngel; Bauer, Hartwig W.; Behrens, Georg; Coon, Joshua J.; Dakna, Mohammed; Decramer, Stéphane; Delles, Christian; Dominiczak, Anna F.; Ehrich, Jochen H. H.; Eitner, Frank; Fliser, Danilo; Frommberger, Moritz; Ganser, Arnold; Girolami, Mark A.; Golovko, Igor; Gwinner, Wilfried; Haubitz, Marion; Herget-Rosenthal, Stefan; Jankowski, Joachim; Jahn, Holger; Jerums, George; Julian, Bruce A.; Kellmann, Markus; Kliem, Volker; Kolch, Walter; Krolewski, Andrzej S.; Luppi, Mario; Massy, Ziad; Melter, Michael; Neusüss, Christian; Novak, Jan; Peter, Karlheinz; Rossing, Kasper; Rupprecht, Harald; Schanstra, Joost P.; Schiffer, Eric; Stolzenburg, Jens-Uwe; Tarnow, Lise; Theodorescu, Dan; Thongboonkerd, Visith; Vanholder, Raymond; Weissinger, Eva M.; Mischak, Harald; Schmitt-Kopplin, Philippe

    2010-01-01

    Because of its availability, ease of collection, and correlation with physiology and pathology, urine is an attractive source for clinical proteomics/peptidomics. However, the lack of comparable data sets from large cohorts has greatly hindered the development of clinical proteomics. Here, we report the establishment of a reproducible, high resolution method for peptidome analysis of naturally occurring human urinary peptides and proteins, ranging from 800 to 17,000 Da, using samples from 3,600 individuals analyzed by capillary electrophoresis coupled to MS. All processed data were deposited in an Structured Query Language (SQL) database. This database currently contains 5,010 relevant unique urinary peptides that serve as a pool of potential classifiers for diagnosis and monitoring of various diseases. As an example, by using this source of information, we were able to define urinary peptide biomarkers for chronic kidney diseases, allowing diagnosis of these diseases with high accuracy. Application of the chronic kidney disease-specific biomarker set to an independent test cohort in the subsequent replication phase resulted in 85.5% sensitivity and 100% specificity. These results indicate the potential usefulness of capillary electrophoresis coupled to MS for clinical applications in the analysis of naturally occurring urinary peptides. PMID:20616184

  6. Naturally occurring IgM antibodies to oxidation-specific epitopes.

    PubMed

    Binder, Christoph J

    2012-01-01

    Naturally occurring antibodies (NAbs) have specificity for both microbial and self antigens, which allows them to act in the first line defense against invading pathogens, as well as in tissue homeostasis by mediating the clearance of cellular debris. This latter recognition of self by NAbs was often thought to reflect the polyreactivity of low affinity antibodies. The finding that oxidation-specific epitopes are dominant targets of naturally occurring IgM antibodies shed light on this and provided novel insights into the understanding of the house keeping functions of NAbs. Oxidation-specific epitopes represent stress-induced or altered self structures that are generated as a consequence of lipidperoxidation during many physiological and pathological situations. Importantly, the same structures have been found in the membranes of dying cells. Only oxidized lipids and dying cells-but not native membrane lipids or viable cells-are recognized by this set of NAbs. Thus, oxidation-specific epitopes represent ideal marks that identify biological waste for its clearance and the neutralization of its pro-inflammatory properties. Furthermore, this binding property of NAbs has also important implications for various chronic inflammatory diseases, including atherosclerosis.

  7. Naturally occurring hybrids of coral reef butterflyfishes have similar fitness compared to parental species

    PubMed Central

    Hobbs, Jean-Paul A.; Pratchett, Morgan S.; Bay, Line K.; van Herwerden, Lynne

    2017-01-01

    Hybridisation can produce evolutionary novelty by increasing fitness and adaptive capacity. Heterosis, or hybrid vigour, has been documented in many plant and animal taxa, and is a notable consequence of hybridisation that has been exploited for decades in agriculture and aquaculture. On the contrary, loss of fitness in naturally occurring hybrid taxa has been observed in many cases. This can have negative consequences for the parental species involved (wasted reproductive effort), and has raised concerns for species conservation. This study evaluates the relative fitness of previously documented butterflyfish hybrids of the genus Chaetodon from the Indo-Pacific suture zone at Christmas Island. Histological examination confirmed the reproductive viability of Chaetodon hybrids. Examination of liver lipid content showed that hybrid body condition was not significantly different from parent species body condition. Lastly, size at age data revealed no difference in growth rates and asymptotic length between hybrids and parent species. Based on the traits measured in this study, naturally occurring hybrids of Chaetodon butterflyfishes have similar fitness to their parental species, and are unlikely to supplant parental species under current environmental conditions at the suture zone. However, given sufficient fitness and ongoing genetic exchange between the respective parental species, hybrids are likely to persist within the suture zone. PMID:28257492

  8. Evaluation of a collagenase generated osteoarthritis biomarker in naturally occurring canine cruciate disease.

    PubMed

    Hayashi, Kei; Kim, Sun-Young; Lansdowne, Jennifer L; Kapatkin, Amy; Déjardin, Loïc M

    2009-01-01

    To determine the clinical value of a novel osteoarthritis (OA) biomarker in detecting canine cruciate disease. Cross sectional clinical study. Dogs (n=22) with cranial cruciate ligament (CCL) rupture and 12 control dogs. Concentrations of collagenase-generated cleavage epitope of type II collagen (Col2-3/4C(long mono), or C2C) in serum, urine, and joint fluid were compared between a group of dogs with CCL rupture and a control group. Correlation of C2C concentrations to the clinical stage of stifle OA was also evaluated. There were no significant differences in C2C concentrations in serum, urine, and joint fluid between groups (P>.05). Subjective scores of lameness, joint effusion, osteophytosis were significantly more severe in the CCL rupture group compared with the control group (P<.05). There was no significant correlation of C2C concentrations with clinical stage of stifle OA (P>.05). This OA biomarker did not detect pathology associated with CCL rupture. Our results suggest that collagenase-specific degradation of type II collagen in articular cartilage may not be involved in the early stage of naturally occurring canine cruciate disease, and that pathology associated with naturally occurring CCL rupture is different from that of experimental OA model. C2C is not clinically useful in detecting CCL rupture in dogs.

  9. Analysis of sense and naturally occurring antisense transcripts of myosin heavy chain in the human myocardium.

    PubMed

    Luther, H P; Podlowski, S; Hetzer, R; Baumann, G

    2001-01-01

    Naturally occurring antisense RNA has the potential to form a duplex with its complementary sense mRNA, thereby regulating protein expression. Previously, we demonstrated considerable amounts of endogenous antisense RNA for both alpha- and beta-myosin heavy chain (MHC) in rat heart suggesting a role in posttranscriptional MHC-regulation (Luther et al. [1997] J Mol Cell Cardiol 29(1):27-35). To evaluate whether antisense RNA is also involved in MHC regulation in human heart we analyzed ventricular myocardium transcripts in nonfailing hearts (n=3) and hearts from patients undergoing heart transplantation (n=5). Investigation of RNA by reverse transcription polymerase chain reaction (RT-PCR) detected an antisense RNA transcript for beta-MHC but none for alpha-MHC. Northern blot analysis of normal and failing hearts detected sense mRNA for beta-MHC, but not alpha-MHC suggesting no functionally relevant levels of alpha-MHC mRNA exist in the human ventricle. The results describe-for the first time-the existence of endogenous polyadenylated MHC antisense transcripts in the human heart. The potential effect of attenuating translation was shown in an in vitro translation assay using a synthetic antisense-oligonucleotide derived from the sequence of the naturally occurring antisense RNA. Copyright 2001 Wiley-Liss, Inc.

  10. Thermal resistance of naturally occurring airborne bacterial spores. [Viking spacecraft dry heat decontamination simulation

    NASA Technical Reports Server (NTRS)

    Puleo, J. R.; Bergstrom, S. L.; Peeler, J. T.; Oxborrow, G. S.

    1978-01-01

    Simulation of a heat process used in the terminal dry-heat decontamination of the Viking spacecraft is reported. Naturally occurring airborne bacterial spores were collected on Teflon ribbons in selected spacecraft assembly areas and subsequently subjected to dry heat. Thermal inactivation experiments were conducted at 105, 111.7, 120, 125, 130, and 135 C with a moisture level of 1.2 mg of water per liter. Heat survivors were recovered at temperatures of 135 C when a 30-h heating cycle was employed. Survivors were recovered from all cycles studied and randomly selected for identification. The naturally occurring spore population was reduced an average of 2.2 to 4.4 log cycles from 105 to 135 C. Heating cycles of 5 and 15 h at temperature were compared with the standard 30-h cycle at 111.7, 120, and 125 C. No significant differences in inactivation (alpha = 0.05) were observed between 111.7 and 120 C. The 30-h cycle differs from the 5- and 15-h cycles at 125 C. Thus, the heating cycle can be reduced if a small fraction (about 0.001 to 0.0001) of very resistant spores can be tolerated.

  11. Definition of target antigens for naturally occurring CD4(+) CD25(+) regulatory T cells.

    PubMed

    Nishikawa, Hiroyoshi; Kato, Takuma; Tawara, Isao; Saito, Kanako; Ikeda, Hiroaki; Kuribayashi, Kagemasa; Allen, Paul M; Schreiber, Robert D; Sakaguchi, Shimon; Old, Lloyd J; Shiku, Hiroshi

    2005-03-07

    The antigenic targets recognized by naturally occurring CD4(+) CD25(+) regulatory T cells (T reg cells) have been elusive. We have serologically defined a series of broadly expressed self-antigens derived from chemically induced mouse sarcomas by serological identification of antigens by recombinant expression cloning (SEREX). CD4(+) CD25(+) T cells from mice immunized with SEREX-defined self-antigens had strong suppressive activity on peptide-specific proliferation of CD4(+) CD25(-) T cells and CD8(+) T cells. The suppressive effect was observed without in vitro T cell stimulation. Foxp3 expression in these CD4(+) CD25(+) T cells from immunized mice was 5-10 times greater than CD4(+) CD25(+) T cells derived from naive mice. The suppressive effect required cellular contact and was blocked by anti-glucocorticoid-induced tumor necrosis factor receptor family-related gene antibody. In vitro suppressive activity essentially disappeared 8 wk after the last immunization. However, it was regained by in vitro restimulation with cognate self-antigen protein but not with control protein. We propose that SEREX-defined self-antigens such as those used in this study represent self-antigens that elicit naturally occurring CD4(+) CD25(+) T reg cells.

  12. AAV-mediated cone rescue in a naturally occurring mouse model of CNGA3-achromatopsia.

    PubMed

    Pang, Ji-jing; Deng, Wen-Tao; Dai, Xufeng; Lei, Bo; Everhart, Drew; Umino, Yumiko; Li, Jie; Zhang, Keqing; Mao, Song; Boye, Sanford L; Liu, Li; Chiodo, Vince A; Liu, Xuan; Shi, Wei; Tao, Ye; Chang, Bo; Hauswirth, William W

    2012-01-01

    Achromatopsia is a rare autosomal recessive disorder which shows color blindness, severely impaired visual acuity, and extreme sensitivity to bright light. Mutations in the alpha subunits of the cone cyclic nucleotide-gated channels (CNGA3) are responsible for about 1/4 of achromatopsia in the U.S. and Europe. Here, we test whether gene replacement therapy using an AAV5 vector could restore cone-mediated function and arrest cone degeneration in the cpfl5 mouse, a naturally occurring mouse model of achromatopsia with a CNGA3 mutation. We show that gene therapy leads to significant rescue of cone-mediated ERGs, normal visual acuities and contrast sensitivities. Normal expression and outer segment localization of both M- and S-opsins were maintained in treated retinas. The therapeutic effect of treatment lasted for at least 5 months post-injection. This study is the first demonstration of substantial, relatively long-term restoration of cone-mediated light responsiveness and visual behavior in a naturally occurring mouse model of CNGA3 achromatopsia. The results provide the foundation for development of an AAV5-based gene therapy trial for human CNGA3 achromatopsia.

  13. Naturally occurring hybrids of coral reef butterflyfishes have similar fitness compared to parental species.

    PubMed

    Montanari, Stefano R; Hobbs, Jean-Paul A; Pratchett, Morgan S; Bay, Line K; van Herwerden, Lynne

    2017-01-01

    Hybridisation can produce evolutionary novelty by increasing fitness and adaptive capacity. Heterosis, or hybrid vigour, has been documented in many plant and animal taxa, and is a notable consequence of hybridisation that has been exploited for decades in agriculture and aquaculture. On the contrary, loss of fitness in naturally occurring hybrid taxa has been observed in many cases. This can have negative consequences for the parental species involved (wasted reproductive effort), and has raised concerns for species conservation. This study evaluates the relative fitness of previously documented butterflyfish hybrids of the genus Chaetodon from the Indo-Pacific suture zone at Christmas Island. Histological examination confirmed the reproductive viability of Chaetodon hybrids. Examination of liver lipid content showed that hybrid body condition was not significantly different from parent species body condition. Lastly, size at age data revealed no difference in growth rates and asymptotic length between hybrids and parent species. Based on the traits measured in this study, naturally occurring hybrids of Chaetodon butterflyfishes have similar fitness to their parental species, and are unlikely to supplant parental species under current environmental conditions at the suture zone. However, given sufficient fitness and ongoing genetic exchange between the respective parental species, hybrids are likely to persist within the suture zone.

  14. Thermal resistance of naturally occurring airborne bacterial spores. [Viking spacecraft dry heat decontamination simulation

    NASA Technical Reports Server (NTRS)

    Puleo, J. R.; Bergstrom, S. L.; Peeler, J. T.; Oxborrow, G. S.

    1978-01-01

    Simulation of a heat process used in the terminal dry-heat decontamination of the Viking spacecraft is reported. Naturally occurring airborne bacterial spores were collected on Teflon ribbons in selected spacecraft assembly areas and subsequently subjected to dry heat. Thermal inactivation experiments were conducted at 105, 111.7, 120, 125, 130, and 135 C with a moisture level of 1.2 mg of water per liter. Heat survivors were recovered at temperatures of 135 C when a 30-h heating cycle was employed. Survivors were recovered from all cycles studied and randomly selected for identification. The naturally occurring spore population was reduced an average of 2.2 to 4.4 log cycles from 105 to 135 C. Heating cycles of 5 and 15 h at temperature were compared with the standard 30-h cycle at 111.7, 120, and 125 C. No significant differences in inactivation (alpha = 0.05) were observed between 111.7 and 120 C. The 30-h cycle differs from the 5- and 15-h cycles at 125 C. Thus, the heating cycle can be reduced if a small fraction (about 0.001 to 0.0001) of very resistant spores can be tolerated.

  15. HIV-1 Tat and Viral Latency: What We Can Learn from Naturally Occurring Sequence Variations.

    PubMed

    Kamori, Doreen; Ueno, Takamasa

    2017-01-01

    Despite the effective use of antiretroviral therapy, the remainder of a latently HIV-1-infected reservoir mainly in the resting memory CD4(+) T lymphocyte subset has provided a great setback toward viral eradication. While host transcriptional silencing machinery is thought to play a dominant role in HIV-1 latency, HIV-1 protein such as Tat, may affect both the establishment and the reversal of latency. Indeed, mutational studies have demonstrated that insufficient Tat transactivation activity can result in impaired transcription of viral genes and the establishment of latency in cell culture experiments. Because Tat protein is one of highly variable proteins within HIV-1 proteome, it is conceivable that naturally occurring Tat mutations may differentially modulate Tat functions, thereby influencing the establishment and/or the reversal of viral latency in vivo. In this mini review, we summarize the recent findings of Tat naturally occurring polymorphisms associating with host immune responses and we highlight the implication of Tat sequence variations in relation to HIV latency.

  16. Assessment of acid-base status of cats with naturally occurring chronic renal failure.

    PubMed

    Elliott, J; Syme, H M; Reubens, E; Markwell, P J

    2003-02-01

    Metabolic acidosis is reported to be a common complication of feline chronic renal failure (CRF) but acid-base status of feline patients with this disease is rarely assessed by general practitioners. A cross-sectional study involving 59 cases of naturally occurring feline CRF was conducted to determine the prevalence of acid-base disturbances. Cases were categorised on the basis of their plasma creatinine concentrations as mild, moderate or severe. A group of 27 clinically healthy, age-matched cats was assessed for comparison. A low venous blood pH (<7.270) was found in 10 of the 19 severe cases (52.6 per cent), three of the 20 moderate cases (15 per cent) and none of the 20 mild cases. Acidaemia was associated with an increased anion gap contributed to by both low plasma bicarbonate and low chloride ion concentrations. Biochemical analysis of urine samples showed urine pH to decrease with increasing severity of renal failure. Urinary loss of bicarbonate was not associated with the occurrence of acidaemia and there was a tendency for urinary ammonium ion excretion to decrease as the severity of renal failure increased. Cats with naturally occurring CRF do not show plasma biochemical evidence of acid-base disturbances until the disease is advanced.

  17. HIV-1 Tat and Viral Latency: What We Can Learn from Naturally Occurring Sequence Variations

    PubMed Central

    Kamori, Doreen; Ueno, Takamasa

    2017-01-01

    Despite the effective use of antiretroviral therapy, the remainder of a latently HIV-1-infected reservoir mainly in the resting memory CD4+ T lymphocyte subset has provided a great setback toward viral eradication. While host transcriptional silencing machinery is thought to play a dominant role in HIV-1 latency, HIV-1 protein such as Tat, may affect both the establishment and the reversal of latency. Indeed, mutational studies have demonstrated that insufficient Tat transactivation activity can result in impaired transcription of viral genes and the establishment of latency in cell culture experiments. Because Tat protein is one of highly variable proteins within HIV-1 proteome, it is conceivable that naturally occurring Tat mutations may differentially modulate Tat functions, thereby influencing the establishment and/or the reversal of viral latency in vivo. In this mini review, we summarize the recent findings of Tat naturally occurring polymorphisms associating with host immune responses and we highlight the implication of Tat sequence variations in relation to HIV latency. PMID:28194140

  18. The role of mesoscale kinetic energy in natural occurring phytoplankton blooms and export in Drake Passage.

    NASA Astrophysics Data System (ADS)

    Davies, A. R.; Veron, F.; Oliver, M. J.

    2014-12-01

    The Southern Ocean is an iron limited, high nitrate, low chlorophyll region that draws considerable attention as a potential site for carbon drawdown through iron fertilization. However, there are no prolonged in-situ observations of the mechanisms driving naturally occurring blooms in this region. Here we present results from an APEX biofloat that continuously profiled the Drake Passage from ~ 2,000 m to the surface every two days. The biofloat measured the development and export of a naturally occurring phytoplankton bloom in the Drake Passage. Our analysis indicates that low levels of mesoscale kinetic energy coincided with the observed phytoplankton bloom. We postulate that low KE level are a precondition for bloom onset in the Drake Passage, which is confirmed by satellite observations. High levels of mesoscale kinetic energy immediately followed the phytoplankton bloom and appear to have facilitated organic carbon export to the deep ocean by changing the neutral density depths of aggregated cells. Furthermore, satellite observations in Drake Passage suggest that high levels of mesoscale kinetic energy limit bloom formation. We suggest that low mesoscale kinetic energy is a precondition for bloom formation in the Drake Passage before other potentially limiting factors become significant (e.g. grazing relation, macronutrients, micronutrients). If mesoscale kinetic energy were to impose a limitation on phytoplankton concentrations across the entire Southern Ocean, there may be regions unsuitable for geoengineered draw down of atmospheric carbon dioxide through large scale iron additions.

  19. Oocyst Discharge, Rumen Metabolism and Performance of Early Weaned Lambs with Naturally Occurring Coccidiosis Fed Monensin

    PubMed Central

    Horton, G. M. J.; Stockdale, P. H. G.

    1981-01-01

    Ninety-six 9.5 kg early-weaned lambs with naturally occurring coccidiosis were fed monensin either at 0, 11, 22, or 33 mg/kg of feed for 105 days. Fecal oocyst discharge during the first three days was highest with monensin 22 mg, lowest with monensin 33 mg and averaged 149.6 × 103 oocysts per gram feces for all lambs. Monensin at 22 mg/kg of feed reduced Eimeria ninakohlyakimovae and E. ahsata oocyst discharge. Organic matter and crude protein digestibilities were highest (P ≤ 0.05) in lambs fed monensin 22 mg/kg of feed. Monensin increased (P ≤ 0.01) rumen ammonia and propionic acid and decreased (P ≤ 0.01) acetic acid. Feeding monensin 33 mg decreased (P ≤ 0.05) feed intake by 5% and had no effect on gain or feed efficiency. Optimal responses were observed with monensin at 11 mg, feed consumption was not affected, gains were 8% higher (P ≤ 0.05) and feed was utilized 9% more efficiently (P ≤ 0.05) than the controls. In conclusion, monensin was an effective therapeutic agent against naturally occurring coccidial infections in early weaned lambs. Performance responses were largest with monensin fed at the rate of 11 mg/kg of feed. PMID:7197187

  20. Harnessing Naturally Occurring Tumor Immunity: A Clinical Vaccine Trial in Prostate Cancer

    PubMed Central

    Tian, Suyan; Suárez-Fariñas, Mayte; Parveen, Salina; Blachère, Nathalie E.; Morris, Michael J.; Slovin, Susan; Scher, Howard I.; Albert, Matthew L.; Darnell, Robert B.

    2010-01-01

    Background Studies of patients with paraneoplastic neurologic disorders (PND) have revealed that apoptotic tumor serves as a potential potent trigger for the initiation of naturally occurring tumor immunity. The purpose of this study was to assess the feasibility, safety, and immunogenicity of an apoptotic tumor-autologous dendritic cell (DC) vaccine. Methods and Findings We have modeled PND tumor immunity in a clinical trial in which apoptotic allogeneic prostate tumor cells were used to generate an apoptotic tumor-autologous dendritic cell vaccine. Twenty-four prostate cancer patients were immunized in a Phase I, randomized, single-blind, placebo-controlled study to assess the safety and immunogenicity of this vaccine. Vaccinations were safe and well tolerated. Importantly, we also found that the vaccine was immunogenic, inducing delayed type hypersensitivity (DTH) responses and CD4+ and CD8+ T cell proliferation, with no effect on FoxP3+ regulatory T cells. A statistically significant increase in T cell proliferation responses to prostate tumor cells in vitro (p = 0.002), decrease in prostate specific antigen (PSA) slope (p = 0.016), and a two-fold increase in PSA doubling time (p = 0.003) were identified when we compared data before and after vaccination. Conclusions An apoptotic cancer cell vaccine modeled on naturally occurring tumor immune responses in PND patients provides a safe and immunogenic tumor vaccine. (ClinicalTrials.gov number NCT00289341). Trial Registration ClinicalTrials.gov NCT00289341 PMID:20824184

  1. Inhibition of fatty acid amide hydrolase by kaempferol and related naturally occurring flavonoids

    PubMed Central

    Thors, L; Belghiti, M; Fowler, C J

    2008-01-01

    Background and purpose: Recent studies have demonstrated that the naturally occurring isoflavone compounds genistein and daidzein inhibit the hydrolysis of anandamide by fatty acid amide hydrolase (FAAH) in the low micromolar concentration range. The purpose of the present study was to determine whether this property is shared by flavonoids. Experimental approach: The hydrolysis of anandamide in homogenates and intact cells was measured using the substrate labelled in the ethanolamine part of the molecule. Key results: Twenty compounds were tested. Among the commonly occurring flavonoids, kaempferol was the most potent, inhibiting FAAH in a competitive manner with a Ki value of 5 μM. Among flavonoids with a more restricted distribution in nature, the two most active toward FAAH were 7-hydroxyflavone (IC50 value of 0.5–1 μM depending on the solvent used) and 3,7-dihydroxyflavone (IC50 value 2.2 μM). All three compounds reduced the FAAH-dependent uptake of anandamide and its metabolism by intact RBL2H3 basophilic leukaemia cells. Conclusions and implications: Inhibition of FAAH is an additional in vitro biochemical property of flavonoids. Kaempferol, 7-hydroxyflavone and 3,7-dihydroxyflavone may be useful as templates for the synthesis of novel compounds, which target several systems that are involved in the control of inflammation and cancer. PMID:18552875

  2. AAV-Mediated Cone Rescue in a Naturally Occurring Mouse Model of CNGA3-Achromatopsia

    PubMed Central

    Dai, Xufeng; Lei, Bo; Everhart, Drew; Umino, Yumiko; Li, Jie; Zhang, Keqing; Mao, Song; Boye, Sanford L.; Liu, Li; Chiodo, Vince A.; Liu, Xuan; Shi, Wei; Tao, Ye; Chang, Bo; Hauswirth, William W.

    2012-01-01

    Achromatopsia is a rare autosomal recessive disorder which shows color blindness, severely impaired visual acuity, and extreme sensitivity to bright light. Mutations in the alpha subunits of the cone cyclic nucleotide-gated channels (CNGA3) are responsible for about 1/4 of achromatopsia in the U.S. and Europe. Here, we test whether gene replacement therapy using an AAV5 vector could restore cone-mediated function and arrest cone degeneration in the cpfl5 mouse, a naturally occurring mouse model of achromatopsia with a CNGA3 mutation. We show that gene therapy leads to significant rescue of cone-mediated ERGs, normal visual acuities and contrast sensitivities. Normal expression and outer segment localization of both M- and S-opsins were maintained in treated retinas. The therapeutic effect of treatment lasted for at least 5 months post-injection. This study is the first demonstration of substantial, relatively long-term restoration of cone-mediated light responsiveness and visual behavior in a naturally occurring mouse model of CNGA3 achromatopsia. The results provide the foundation for development of an AAV5-based gene therapy trial for human CNGA3 achromatopsia. PMID:22509403

  3. Drosophila TRPA1 channel is required to avoid the naturally occurring insect repellent citronellal

    PubMed Central

    Kwon, Young; Kim, Sang Hoon; Ronderos, David S.; Lee, Youngseok; Akitake, Bradley; Woodward, Owen M.; Guggino, William B.; Smith, Dean P.; Montell, Craig

    2010-01-01

    Summary Plants produce naturally occurring insect repellents, such as citronellal, which is the main component of citronellal oil and is among the most widely-used-naturally-occurring insect repellents. However, the molecular pathways through which insects sense botanical repellents are unknown. Here, we showed that Drosophila used two pathways for direct avoidance of citronellal. The olfactory co-receptor, Or83b, which is required for the response to the synthetic repellent DEET, contributed to citronellal repulsion, and was essential for citronellal-evoked action potentials. Mutations affecting the Ca2+-permeable cation channel, TRPA1 resulted in a comparable defect in avoiding citronellal vapor. The TRPA1-dependent aversion to citronellal relied on a G protein/phospholipase C (PLC) signaling cascade, rather than direct detection of citronellal by TRPA1. Loss of TRPA1, Gq or PLC caused an increase in the frequency of citronellal-evoked action potentials in olfactory receptor neurons. Absence of the Ca2+-activated K+ channel, Slowpoke, resulted in a similar impairment in citronellal avoidance, and an increase in the frequency of action potentials. These results suggest that TRPA1 is required for activation of a BK channel to modulate citronellal-evoked action potentials, and for aversion to citronellal. In contrast to Drosophila TRPA1, Anopheles gambiae TRPA1 was directly and potently activated by citronellal, thereby raising the possibility that mosquito TRPA1 may be a target for developing improved repellents to reduce insect-borne diseases such as malaria. PMID:20797863

  4. Inhibition of N-nitrosodiethylamine carcinogenesis in mice by naturally occurring organosulfur compounds and monoterpenes.

    PubMed

    Wattenberg, L W; Sparnins, V L; Barany, G

    1989-05-15

    Naturally occurring compounds belonging to two chemical groups were studied for their capacities to inhibit N-nitrosodiethylamine (NDEA)-induced carcinogenesis in female A/J mice. One group consists of organosulfur compounds found in Allium species, including garlic, onions, leeks, and shallots, and the other, two monoterpenes, i.e., D-limonene and D-carvone. In an initial experiment, in which organosulfur compounds were investigated, diallyl disulfide, allyl mercaptan, and allyl methyl disulfide were found to produce a marked inhibition of NDEA-induced neoplasia of the forestomach when the test compounds were administered p.o. 96 and 48 h prior to NDEA. The most potent was diallyl disulfide which reduced forestomach tumor formation by more than 90%. Pulmonary adenoma formation also was inhibited but to a considerably lesser extent, i.e., about 30%. In three additional experiments, test compounds were given p.o. either 15 min or 1 h prior to NDEA. Under these conditions diallyl disulfide and allyl mercaptan again inhibited forestomach tumor formation substantially, i.e., greater than 75%, and pulmonary adenoma formation marginally, i.e., less than 20%. In these experiments D-limonene and D-carvone were tested and reduced forestomach tumor formation by slightly over 60% and pulmonary adenoma formation by about 35%. The results of these studies provide evidence of an increasing diversity of naturally occurring compounds having the capacity to inhibit nitrosamine carcinogenesis.

  5. Computational Assessment of Naturally Occurring Neutron and Photon Background Radiation Produced by Extraterrestrial Sources

    SciTech Connect

    Miller, Thomas Martin; de Wet, Wouter C.; Patton, Bruce W.

    2015-10-28

    In this study, a computational assessment of the variation in terrestrial neutron and photon background from extraterrestrial sources is presented. The motivation of this assessment is to evaluate the practicality of developing a tool or database to estimate background in real time (or near–real time) during an experimental measurement or to even predict the background for future measurements. The extraterrestrial source focused on during this assessment is naturally occurring galactic cosmic rays (GCRs). The MCNP6 transport code was used to perform the computational assessment. However, the GCR source available in MCNP6 was not used. Rather, models developed and maintained by NASA were used to generate the GCR sources. The largest variation in both neutron and photon background spectra was found to be caused by changes in elevation on Earth's surface, which can be as large as an order of magnitude. All other perturbations produced background variations on the order of a factor of 3 or less. The most interesting finding was that ~80% and 50% of terrestrial background neutrons and photons, respectively, are generated by interactions in Earth's surface and other naturally occurring and man-made objects near a detector of particles from extraterrestrial sources and their progeny created in Earth's atmosphere. In conclusion, this assessment shows that it will be difficult to estimate the terrestrial background from extraterrestrial sources without a good understanding of a detector's surroundings. Therefore, estimating or predicting background during a measurement environment like a mobile random search will be difficult.

  6. Monitoring Natural Occurring Asbestos in ophiolite sequences and derived soils: implication with human activities

    NASA Astrophysics Data System (ADS)

    Punturo, Rosalda; Bloise, Andrea; Cirrincione, Rosolino

    2016-04-01

    The present contribution focuses on soils that developed on serpentinite-metabasite bedrocks, which could potentially be rich in asbestos minerals and, as a consequence, have a negative impact on agricultural activity and on environmental quality. In order to investigate the natural occurrences of asbestos (NOA) on the surface of the soil formed from serpentinites and metabasite, we selected a study area located in Sila Piccola (Calabrian Peloritani Orogen, southern Italy), where previous studies highlighted the presence of asbestiform minerals within the large ophiolitic sequences that crop out (Punturo et al., 2015; Bloise et al., 2015). Agricultural soil samples have been collected mainly close to urban centres and characterized by using different analytical techniques such as X-ray powder diffraction (XRPD), transmission electron microscopy combined with energy dispersive spectrometry (TEM-EDS), thermogravimetry (TG) and differential scanning calorimetry (DSC) Results pointed out as all the collected soil samples contain serpentine minerals (e.g., chrysotile), asbestos amphiboles, clays, chlorite, muscovite, plagioclase and iron oxides in various amounts. Electron microscope images of the soils show that their contain a variety of aggregating agents such as organic matter and clay in which individual fibres of chrysotile and tremolite-actinolite are trapped. The investigation showed that both serpentinite and metabasite rocks act as a perennial source of contamination for the agriculture lands because of the high amount of tremolite-actinolite found in the studied soil samples developed on such lithotypes. Even if asbestiform minerals usually occur in aggregates which cannot be suspended in the air, agricultural activities such as plowing can destroy these soil aggregates with the creation of dust containing inhalable asbestos fibres that evolve into airborne increasing the exposure of population to them. Since the dispersion of fibres could be associated with

  7. Unravelling a 'miner's myth' that environmental contamination in mining towns is naturally occurring.

    PubMed

    Kristensen, Louise Jane; Taylor, Mark Patrick

    2016-08-01

    Australia has a long history of metal mining and smelting. Extraction and processing have resulted in elevated levels of toxic metals surrounding mining operations, which have adverse health effects, particularly to children. Resource companies, government agencies and employees often construct 'myths' to down play potential exposure risks and responsibility arising from operating emissions. Typical statements include: contaminants are naturally occurring, the wind blows emissions away from residential areas, contaminants are not bioavailable, or the problem is a legacy issue and not related to current operations. Evidence from mining and smelting towns shows that such 'myths' are exactly that. In mining towns, the default and primary defence against contamination is that elevated metals in adjacent urban environments are from the erosion and weathering of the ore bodies over millennia-hence 'naturally occurring'. Not only is this a difficult argument to unravel from an evidence-based perspective, but also it causes confusion and delays remediation work, hindering efforts to reduce harmful exposures to children. An example of this situation is from Broken Hill, New South Wales, home to one of the world's largest lead-zinc-silver ore body, which has been mined continuously for over 130 years. Environmental metal concentration and lead isotopic data from soil samples collected from across Broken Hill are used to establish the nature and timing of lead contamination. We use multiple lines of evidence to unravel a 'miner's myth' by evaluating current soil metal concentrations and lead isotopic compositions, geological data, historical environmental assessments and old photographic evidence to assess the impacts from early smelting along with mining to the surface soils in the city.

  8. Naturally occurring conjugated octadecatrienoic acids are strong inhibitors of prostaglandin biosynthesis.

    PubMed

    Nugteren, D H; Christ-Hazelhof, E

    1987-03-01

    Fatty acids from natural sources (mostly seed oils) were isolated and assayed for their effect on the bioconversion of arachidonic acid into prostaglandin E2, using sheep vesicular gland microsomes. Homologues and isomers of the naturally occurring fatty acids, obtained by chemical modification and/or organic synthetic methods, were also tested. Two very active cyclooxygenase inhibitors were discovered, namely jacarandic acid (8Z, 10E, 12Z-octadecatrienoic acid), isolated from Jacaranda mimosifolia, the concentration which gives 50% inhibition ([I]50) being 2.4 microM and the synthetic 8Z, 10E, 12E-octadecatrienoic acid, having an [I]50 of 1.0 microM. Under the conditions of the assay (75 microM substrate), earlier described potent inhibitors showed the following [I]50's: indomethacin: 1.3 microM; 9,12-octadecadiynoic acid: 1.3 microM, 8Z, 12E, 14Z-eicosatrienoic acid: 2.7 microM; 5,8,11,14-eicosatetraynoic acid: 4.4 microM. At a concentration of about half that of the substrate, the following naturally occurring fatty acids revealed inhibition ([I]50): columbinic acid (29 microM), calendulic acid (31 microM), liagoric acid (31 microM), ximenynic acid (39 microM), crepenynic acid (40 microM) and timnodonic acid (43 microM). Other fatty acids, and some of the above acids, were converted themselves more or less rapidly, mostly into conjugated monohydroxy fatty acids.

  9. Preclinical characterization of naturally occurring polyketide cyclophilin inhibitors from the sanglifehrin family.

    PubMed

    Gregory, Matthew A; Bobardt, Michael; Obeid, Susan; Chatterji, Udayan; Coates, Nigel J; Foster, Teresa; Gallay, Philippe; Leyssen, Pieter; Moss, Steven J; Neyts, Johan; Nur-e-Alam, Mohammad; Paeshuyse, Jan; Piraee, Mahmood; Suthar, Dipen; Warneck, Tony; Zhang, Ming-Qiang; Wilkinson, Barrie

    2011-05-01

    Cyclophilin inhibitors currently in clinical trials for hepatitis C virus (HCV) are all analogues of cyclosporine (CsA). Sanglifehrins are a group of naturally occurring cyclophilin binding polyketides that are structurally distinct from the cyclosporines and are produced by a microorganism amenable to biosynthetic engineering for lead optimization and large-scale production by fermentation. Preclinical characterization of the potential utility of this class of compounds for the treatment of HCV revealed that the natural sanglifehrins A to D are all more potent than CsA at disrupting formation of the NS5A-CypA, -CypB, and -CypD complexes and at inhibition of CypA, CypB, and CypD isomerase activity. In particular, sanglifehrin B (SfB) was 30- to 50-fold more potent at inhibiting the isomerase activity of all Cyps tested than CsA and was also shown to be a more potent inhibitor of the 1b subgenomic replicon (50% effective concentrations [EC50s] of 0.070 μM and 0.16 μM in Huh 5-2 and Huh 9-13 cells, respectively). Physicochemical and mouse pharmacokinetic analyses revealed low oral bioavailability (F<4%) and low solubility (<25 μM), although the half-lives (t1/2) of SfA and SfB in mouse blood after intravenous (i.v.) dosing were long (t1/2>5 h). These data demonstrate that naturally occurring sanglifehrins are suitable lead compounds for the development of novel analogues that are less immunosuppressive and that have improved metabolism and pharmacokinetic properties.

  10. A naturally occurring deletion mutant of figwort mosaic virus (caulimovirus) is generated by RNA splicing.

    PubMed

    Scholthof, H B; Wu, F C; Richins, R D; Shepherd, R J

    1991-09-01

    A naturally occurring deletion mutant is observed in plants infected with figwort mosaic virus (FMV), a caulimovirus. The encapsidated mutant genome is formed spontaneously in association with two different strains of FMV in four host plant species. The mutant also appears when cloned wild-type viral DNA is used as the inoculum. The deletion mutant alone is not infectious and it appears unable to replicate after its formation, even in the presence of wild-type virus. The gene for chloramphenicol acetyltransferase was inserted at different positions in the deletion mutant genome, and subsequent transient assays showed that gene expression of the mutant occurs despite the deletion. Sequence analyses of the mutant genome revealed a deletion of 1237-bp segment encompassing a major portion of the coat protein gene and the 5' end of the downstream reverse transcriptase gene. This deletion is associated with consensus signals for RNA splicing including the conserved 5' and 3' splice sites plus surrounding sequences, putative branch point(s) for lariat formation, and an extremely high adenosine content (41%) of the removed fragment. This suggests that splicing of the FMV full-length transcript has occurred prior to reverse transcription and this accounts for the presence and accumulation of encapsidated DNAs with the same deletion.

  11. Solubilisation of some naturally occurring metal-bearing minerals, limescale and lead phosphate by Aspergillus niger.

    PubMed

    Sayer, J A; Kierans, M; Gadd, G M

    1997-09-01

    The ability of the soil fungus Aspergillus niger to tolerate and solubilise seven naturally occurring metal-bearing minerals, limescale and lead phosphate was investigated. A. niger was able to solubilise four of the test insoluble compounds when incorporated into solid medium: cuprite (CuO2), galena (PbS), rhodochrosite (Mn(CO3)x) and limescale (CaCO3). A. niger was able to grow on all concentrations of all the test compounds, whether solubilisation occurred or not, with no reduction in growth rate from the control. In some cases, stimulation of growth occurred, most marked with the phosphate-containing mineral, apatite. Precipitation of insoluble copper and manganese oxalate crystals under colonies growing on agar amended with cuprite and rhodochrosite was observed after 1-2 days growth at 25 degrees C. This process of oxalate formation represents a reduction in bioavailability of toxic cations, and could represent an important means of toxic metal immobilisation of physiological and environmental significance.

  12. Quantification and Radiological Risk Estimation Due to the Presence of Natural Radionuclides in Maiganga Coal, Nigeria

    PubMed Central

    Kolo, Matthew Tikpangi; Khandaker, Mayeen Uddin; Amin, Yusoff Mohd; Abdullah, Wan Hasiah Binti

    2016-01-01

    Following the increasing demand of coal for power generation, activity concentrations of primordial radionuclides were determined in Nigerian coal using the gamma spectrometric technique with the aim of evaluating the radiological implications of coal utilization and exploitation in the country. Mean activity concentrations of 226Ra, 232Th, and 40K were 8.18±0.3, 6.97±0.3, and 27.38±0.8 Bq kg-1, respectively. These values were compared with those of similar studies reported in literature. The mean estimated radium equivalent activity was 20.26 Bq kg-1 with corresponding average external hazard index of 0.05. Internal hazard index and representative gamma index recorded mean values of 0.08 and 0.14, respectively. These values were lower than their respective precautionary limits set by UNSCEAR. Average excess lifetime cancer risk was calculated to be 0.04×10−3, which was insignificant compared with 0.05 prescribed by ICRP for low level radiation. Pearson correlation matrix showed significant positive relationship between 226Ra and 232Th, and with other estimated hazard parameters. Cumulative mean occupational dose received by coal workers via the three exposure routes was 7.69 ×10−3 mSv y-1, with inhalation pathway accounting for about 98%. All radiological hazard indices evaluated showed values within limits of safety. There is, therefore, no likelihood of any immediate radiological health hazards to coal workers, final users, and the environment from the exploitation and utilization of Maiganga coal. PMID:27348624

  13. Quantification and Radiological Risk Estimation Due to the Presence of Natural Radionuclides in Maiganga Coal, Nigeria.

    PubMed

    Kolo, Matthew Tikpangi; Khandaker, Mayeen Uddin; Amin, Yusoff Mohd; Abdullah, Wan Hasiah Binti

    2016-01-01

    Following the increasing demand of coal for power generation, activity concentrations of primordial radionuclides were determined in Nigerian coal using the gamma spectrometric technique with the aim of evaluating the radiological implications of coal utilization and exploitation in the country. Mean activity concentrations of 226Ra, 232Th, and 40K were 8.18±0.3, 6.97±0.3, and 27.38±0.8 Bq kg-1, respectively. These values were compared with those of similar studies reported in literature. The mean estimated radium equivalent activity was 20.26 Bq kg-1 with corresponding average external hazard index of 0.05. Internal hazard index and representative gamma index recorded mean values of 0.08 and 0.14, respectively. These values were lower than their respective precautionary limits set by UNSCEAR. Average excess lifetime cancer risk was calculated to be 0.04×10-3, which was insignificant compared with 0.05 prescribed by ICRP for low level radiation. Pearson correlation matrix showed significant positive relationship between 226Ra and 232Th, and with other estimated hazard parameters. Cumulative mean occupational dose received by coal workers via the three exposure routes was 7.69 ×10-3 mSv y-1, with inhalation pathway accounting for about 98%. All radiological hazard indices evaluated showed values within limits of safety. There is, therefore, no likelihood of any immediate radiological health hazards to coal workers, final users, and the environment from the exploitation and utilization of Maiganga coal.

  14. Low level measurements of natural radionuclides in soil samples around a coal-fired power plant

    NASA Astrophysics Data System (ADS)

    Rosner, G.; Bunzl, K.; Hötzl, H.; Winkler, R.

    1984-06-01

    To detect a possible contribution of airborne radioactivity from stack effluents to the soil radioactivity, several radionuclides in the soil around a coal-fired power plant have been determined. A plant situated in a rural region of Bavaria was selected to minimize contributions from other civilisatory sources. The soil sampling network consisted of 5 concentric circles with diameters between 0.4 and 5.2 km around the plant, 16 sampling points being distributed regularly on each circle. Radiochemical analysis techniques for 210Pb and 210Po in soil samples of several grams had to be developed. They include a wet dissolution procedure, simultaneous precipitation of lead and polonium as the sulfides, purification via lead sulfate, counting of the lead as the chromate in a low-level beta counter and alpha spectrometric determination of the 210Po in a gridded ionization chamber. The 238U, 226Ra, 232Th and 40K were counted by low level gamma spectrometry. Specific activities found were in the range of 0.7 to 2.0 pCi g -1 for 210Pb and 0.3 to 1.6 pCi g -1 for 226Ra. The distribution patterns of 210Po and 210Pb around the plant were found to be similar. They were different, however, from that of 226Ra. The highest 210Pb/ 226Ra activity ratio was 3.9 at a distance of 0.76 km SSE from the plant. Nevertheless, the evidence is not considered to be sufficient to attribute these observations unambiguously to plant releases.

  15. Distribution of natural and anthropogenic radionuclides in beach sand samples from Mediterranean Coast of Turkey

    NASA Astrophysics Data System (ADS)

    Özmen, S. F.; Cesur, A.; Boztosun, I.; Yavuz, M.

    2014-10-01

    Following Fukushima Dai-ichi Nuclear Power Plant accident, a huge amount of radionuclides were released in atmosphere and ocean. It's impact on the environment is of great concern to the good of the public at large. In this regard environmental radioactivity monitoring such as external dose rate and radioactivity measurements in environmental samples has been carried out. For this purpose, several beach sand samples were collected from south coast of the Turkey in September 2011 and radioactivity concentrations of 226Ra (238U), 228Ac (232Th), 40K, 134Cs and 137Cs were determined by gamma spectrometry using a high-purity Germanium detector. The measured activity concentrations in beach sand samples ranged from 4.0±0.5 to 21.5±1.8 Bq/kg, 1.8±0.4 to 27.9±2.4 Bq/kg, 19.0±2.2 to 590.3±28.6 Bq/kg and 0.1±0.0 to 1.0±0.1 Bq/kg for 226Ra, 232Th, 40K and 137Cs, respectively. However there was no sign of 134Cs in the sample spectrum after Fukushima Dai-ichi Nuclear Power Plant accident. Hence we can safely conclude that there was no significant material transfer from Fukushima to Turkey. The other activities are in good agreement with the published results of neighboring areas. The absorbed gamma dose rate (D) and the annual effective dose (AED) of beach sand samples were below the world wide average implying that the radiation hazard is insignificant. The data presented in this study would also be very useful to determine the possible future effects of the nuclear power plant to the environment.

  16. Transfer factors of natural radionuclides and (137)Cs from soil to plants used in traditional medicine in central Serbia.

    PubMed

    Djelic, Gorica; Krstic, Dragana; Stajic, Jelena M; Milenkovic, Biljana; Topuzovic, Marina; Nikezic, Dragoslav; Vucic, Dusica; Zeremski, Tijana; Stankovic, Milan; Kostic, Dragana

    2016-07-01

    Transfer factors of natural radionuclides and (137)Cs from soil to plants used in traditional medicine were determined. The transfer factors (TF) were calculated as Bq kg(-1) of dry plant per Bq kg(-1) of dry soil. Mass activity concentrations of (226)Ra, (232)Th, (40)K and (137)Cs in soil and plant samples were measured with high purity germanium detector (HPGe). The concentrations of As, Co, Cr, Cu, Mn, Ni, Pb and Zn were determined, as well as the cation exchange capacity (CEC) and the content of exchangeable cations (Ca, Mg, K, Na). Wide ranges of values were obtained for all the metals, especially for Cr and Ni. The Absalom model was used for determination of the amount of (137)Cs transferred from soil to plant based on soil characteristics such as pH, exchangeable potassium, humus and clay contents. The estimated transfer factors were in the range from 0.011 to 0.307 with an arithmetic mean of 0.071, median of 0.050, geometric mean of 0.053 and geometric standard deviation (GSD) of 2.08. This value agreed well with that calculated from the measurements of 0.069, geometric mean 0.040 and GSD 3.19. Correlations between radionuclides, metals, physicochemical properties and transfer factors were determined by Spearman correlation coefficient. There was a strong positive correlation between (137)Cs transfer factor and the ratio of transfer factor for K and (137)Cs. Principal Component Analysis (PCA) was performed in order to identify some pattern of data. Copyright © 2016. Published by Elsevier Ltd.

  17. Uranium and other natural radionuclides in the sediments of a Mediterranean fjord-like embayment, Amvrakikos Gulf (Ionian Sea), Greece.

    PubMed

    Papaefthymiou, H; Athanasopoulos, D; Papatheodorou, G; Iatrou, M; Geraga, M; Christodoulou, D; Kordella, S; Fakiris, E; Tsikouras, B

    2013-08-01

    The distribution of the natural radionuclides ((238)U, (232)Th, (226)Ra, (40)K) and the artificial (137)Cs was studied in sediment cores collected from Amvrakikos Gulf, a seasonal anoxic marine basin, using γ-ray spectrometry. The activity of radionuclides, along with the concentrations of Fe and Mn, were also studied in relation to the total organic carbon and the granulometric fractions of the sediments. The results obtained revealed higher (238)U activity concentrations in all the examined sediment samples compared to the world and Greek average values for soil. The high activity values of (238)U are attributed, besides the lattice-held fraction, to phosphate fertilizer inputs in the Gulf via major rivers and/or to alteration processes of phosphate ores located mainly in the drainage basin of the river Louros. The elevated activity values of (40)K could be attributed to the mineralogical composition of the sediments and to phosphate fertilizers containing potassium. Organic matter seems to be a more efficient sorbent for U than clay minerals and amorphous Fe and Mn-oxyhydroxides. Scanning electron microscopy, together with qualitative analysis of some smectites, reveals the occurrence of U, suggesting a limited absorption of U onto clay minerals. The applied BCR sequential extraction procedure revealed that U was found mainly in the refractory phase or associated with organic matter and to a lesser extent as surface-coating oxides, with the exception of one sediment core which is characterized by high content of fresh marine organic matter and presents high percentage of U in the exchangeable fraction. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Radionuclide trap

    DOEpatents

    McGuire, Joseph C.

    1978-01-01

    The deposition of radionuclides manganese-54, cobalt-58 and cobalt-60 from liquid sodium coolant is controlled by providing surfaces of nickel or high nickel alloys to extract the radionuclides from the liquid sodium, and by providing surfaces of tungsten, molybdenum or tantalum to prevent or retard radionuclide deposition.

  19. Radionuclide removal by apatite

    SciTech Connect

    Rigali, Mark J.; Brady, Patrick V.; Moore, Robert C.

    2016-12-01

    In this study, a growing body of research supports widespread future reliance on apatite for radioactive waste cleanup. Apatite is a multi-functional radionuclide sorbent that lowers dissolved radionuclide concentrations by surface sorption, ion exchange, surface precipitation, and by providing phosphate to precipitate low-solubility radionuclide-containing minerals. Natural apatites are rich in trace elements, and apatite’s stability in the geologic record suggest that radionuclides incorporated into apatite, whether in a permeable reactive barrier or a waste form, are likely to remain isolated from the biosphere for long periods of time. Here we outline the mineralogic and surface origins of apatite-radionuclide reactivity and show how apatites might be used to environmental advantage in the future.

  20. Radionuclide removal by apatite

    DOE PAGES

    Rigali, Mark J.; Brady, Patrick V.; Moore, Robert C.

    2016-12-01

    In this study, a growing body of research supports widespread future reliance on apatite for radioactive waste cleanup. Apatite is a multi-functional radionuclide sorbent that lowers dissolved radionuclide concentrations by surface sorption, ion exchange, surface precipitation, and by providing phosphate to precipitate low-solubility radionuclide-containing minerals. Natural apatites are rich in trace elements, and apatite’s stability in the geologic record suggest that radionuclides incorporated into apatite, whether in a permeable reactive barrier or a waste form, are likely to remain isolated from the biosphere for long periods of time. Here we outline the mineralogic and surface origins of apatite-radionuclide reactivity andmore » show how apatites might be used to environmental advantage in the future.« less

  1. Beneficial Effects of Autologous Bone Marrow-Derived Mesenchymal Stem Cells in Naturally Occurring Tendinopathy

    PubMed Central

    Smith, Roger Kenneth Whealands; Werling, Natalie Jayne; Dakin, Stephanie Georgina; Alam, Rafiqul; Goodship, Allen E.; Dudhia, Jayesh

    2013-01-01

    Tendon injuries are a common age-related degenerative condition where current treatment strategies fail to restore functionality and normal quality of life. This disease also occurs naturally in horses, with many similarities to human tendinopathy making it an ideal large animal model for human disease. Regenerative approaches are increasingly used to improve outcome involving mesenchymal stem cells (MSCs), supported by clinical data where injection of autologous bone marrow derived MSCs (BM-MSCs) suspended in marrow supernatant into injured tendons has halved the re-injury rate in racehorses. We hypothesized that stem cell therapy induces a matrix more closely resembling normal tendon than the fibrous scar tissue formed by natural repair. Twelve horses with career-ending naturally-occurring superficial digital flexor tendon injury were allocated randomly to treatment and control groups. 1X107 autologous BM-MSCs suspended in 2 ml of marrow supernatant were implanted into the damaged tendon of the treated group. The control group received the same volume of saline. Following a 6 month exercise programme horses were euthanized and tendons assessed for structural stiffness by non-destructive mechanical testing and for morphological and molecular composition. BM-MSC treated tendons exhibited statistically significant improvements in key parameters compared to saline-injected control tendons towards that of normal tendons and those in the contralateral limbs. Specifically, treated tendons had lower structural stiffness (p<0.05) although no significant difference in calculated modulus of elasticity, lower (improved) histological scoring of organisation (p<0.003) and crimp pattern (p<0.05), lower cellularity (p<0.007), DNA content (p<0.05), vascularity (p<0.03), water content (p<0.05), GAG content (p<0.05), and MMP-13 activity (p<0.02). Treatment with autologous MSCs in marrow supernatant therefore provides significant benefits compared to untreated tendon repair in

  2. The effect of various naturally occurring metal-binding compounds on the electrochemical behavior of aluminum

    SciTech Connect

    Hansen, D.C.; McCafferty, E.

    1996-01-01

    Naturally occurring biological molecules are of considerable interest as possible corrosion inhibitors because of increased attention on the development of environmentally compatible, nonpolluting corrosion inhibitors. A hydroxamate yeast siderophore (rhodotorulic acid), a catecholate bacterial siderophore (parabactin), an adhesive protein from the blue mussel Mytilus edulis, and two metal-binding compounds isolated from the tomato and sunflower roots, namely, chlorogenic and caffeic acid, respectively, were adsorbed from solution onto pure aluminum (99.9995%) and their effect on the critical pitting potential and polarization resistance in deaerated 0.1 M NaCl was measured. These measurements were made using anodic polarization and ac impedance spectroscopy. The catechol-containing siderophore has an inhibitive effect on the critical pitting potential of aluminum in 0.1 M NaCl and increases the polarization resistance of the metal over time. The adhesive protein from the blue mussel is also effective in inhibiting the pitting of aluminum.

  3. The corrosion inhibition of iron and aluminum by various naturally occurring biological molecules

    SciTech Connect

    McCafferty, E.; Hansen, D.C.

    1995-12-31

    Biological polymers that exhibit a strong affinity for metal surfaces are increasingly becoming the focus of research toward the development of environmentally friendly corrosion inhibitors. This paper deals with the use of various naturally occurring organic molecules as corrosion inhibitors for iron or aluminum. Among the organic molecules considered are catecholate and hydroxamate siderophores isolated from bacteria, the adhesive protein from the blue mussel Mytilus edulis L, and caffeic acid and chlorogenic acid. FTIR analysis, anodic polarization curves, and AC impedance measurements were used to determine the adsorption and effectiveness of the various organic molecules as corrosion inhibitors. Parabactin, a catecholate siderophore, was effective in inhibiting both the corrosion of iron in hydrochloric acid and the pitting of aluminum in 0.1 M sodium chloride. The adhesive protein from the blue mussel was also effective in inhibiting the pitting of aluminum.

  4. Tetra­hydro­berberine, a pharmacologically active naturally occurring alkaloid

    PubMed Central

    Pingali, Subramanya; Donahue, James P.; Payton-Stewart, Florastina

    2015-01-01

    Tetra­hydro­berberine (systematic name: 9,10-dimeth­oxy-5,8,13,13a-tetra­hydro-6H-benzo[g][1,3]benzodioxolo[5,6-a]quinolizine), C20H21NO4, a widely distributed naturally occurring alkaloid, has been crystallized as a racemic mixture about an inversion center. A bent conformation of the mol­ecule is observed, with an angle of 24.72 (5)° between the arene rings at the two ends of the reduced quinolizinium core. The inter­molecular hydrogen bonds that play an apparent role in crystal packing are 1,3-benzodioxole –CH2⋯OCH3 and –OCH3⋯OCH3 inter­actions between neighboring mol­ecules. PMID:25836282

  5. Systems and methods for facilitating hydrogen storage using naturally occurring nanostructure assemblies

    DOEpatents

    Fliermans,; Carl, B [Augusta, GA

    2012-08-07

    Some or all of the needs above can be addressed by embodiments of the invention. According to embodiments of the invention, systems and methods for facilitating hydrogen storage using naturally occurring nanostructure assemblies can be implemented. In one embodiment, a method for storing hydrogen can be provided. The method can include providing diatoms comprising diatomaceous earth or diatoms from a predefined culture. In addition, the method can include heating the diatoms in a sealed environment in the presence of at least one of titanium, a transition metal, or a noble metal to provide a porous hydrogen storage medium. Furthermore, the method can include exposing the porous hydrogen storage medium to hydrogen. In addition, the method can include storing at least a portion of the hydrogen in the porous hydrogen storage medium.

  6. Poly(anhydride-esters) comprised exclusively of naturally occurring antimicrobials and EDTA: antioxidant and antibacterial activities.

    PubMed

    Carbone-Howell, Ashley L; Stebbins, Nicholas D; Uhrich, Kathryn E

    2014-05-12

    Carvacrol, thymol, and eugenol are naturally occurring phenolic compounds known to possess antimicrobial activity against a range of bacteria, as well as antioxidant activity. Biodegradable poly(anhydride-esters) composed of an ethylenediaminetetraacetic acid (EDTA) backbone and antimicrobial pendant groups (i.e., carvacrol, thymol, or eugenol) were synthesized via solution polymerization. The resulting polymers were characterized to confirm their chemical composition and understand their thermal properties and molecular weight. In vitro release studies demonstrated that polymer hydrolytic degradation was complete after 16 days, resulting in the release of free antimicrobials and EDTA. Antioxidant and antibacterial assays determined that polymer release media exhibited bioactivity similar to that of free compound, demonstrating that polymer incorporation and subsequent release had no effect on activity. These polymers completely degrade into components that are biologically relevant and have the capability to promote preservation of consumer products in the food and personal care industries via antimicrobial and antioxidant pathways.

  7. Synthesis and self-assembly of nearly monodisperse nanoparticles of a naturally occurring polymer.

    PubMed

    Cai, Tong; Hu, Zhibing; Marquez, Manuel

    2004-08-31

    Nearly monodisperse nanoparticles have been synthesized based on a naturally occurring polymer of hydropropylcellulose (HPC) using precipitation polymerization method. It is found that when the polydispersity index value of the HPC nanoparticles is less than 1.10, the HPC particles can self-assemble into an ordered structure, displaying bright colors. UV-visible spectroscopy reveals that the color shifts to a lower wavelength as the interparticle distance decreases following the Bragg diffraction equation. The HPC nanoparticle assembly in water has been further stabilized by covalently bonding neighboring particles to form a three-dimensional network. This network contains a large amount of water similar to a conventional bulk gel but displays colors as a result of its ordered structure.

  8. A unique case of naturally occurring mummification of human brain tissue.

    PubMed

    Radanov, S; Stoev, S; Davidov, M; Nachev, S; Stanchev, N; Kirova, E

    1992-01-01

    When skulls and bones were exhumed from a mass grave in Bulgaria and subjected to medicolegal examination they were found to originate from 39 humans aged 36-60 years old who had been buried approximately 45-50 years ago. Solid structures which strongly resembled shrunken human brain tissue were found inside 2 intact skulls. Among other bones 5 similar structures were found one of which was an almost entirely preserved human brain, and the others were fragments from different regions of the human brain. Samples of these structures were immersed in 15% aqueous glycerol solution to soften and were examined by light and electron microscopy. Samples of this material and of fresh human brain were subjected to elementary atomic spectral analysis. These complex studies indicated the samples to be naturally mummified human brain tissue and that this process had occurred due to specific conditions within the cranial cavities after burial.

  9. Inhibition of T cell receptor signaling by cholesterol sulfate, a naturally occurring derivative of membrane cholesterol

    PubMed Central

    Wang, Feng; Beck-García, Katharina; Zorzin, Carina; Schamel, Wolfgang W. A.; Davis, Mark M.

    2016-01-01

    Most adaptive immune responses require the activation of specific T cells through the T cell antigen receptor–CD3 complex (TCR). Here we show that cholesterol sulfate (CS), a naturally occurring analog of cholesterol, inhibits CD3 ITAM phosphorylation, a crucial first step in T cell activation. Biochemical studies show that CS disrupted TCR multimers, apparently by displacing cholesterol, known to bind TCRβ. Moreover, CS-deficient mice displayed a heightened sensitivity to a self-antigen, whereas increasing CS content by intrathymic injection inhibited thymic selection, indicating that this molecule is an intrinsic regulator of thymocyte development. These results reveal a regulatory role for CS in TCR signaling and thymic selection, highlighting the importance of the membrane microenvironment in modulating cell surface receptor activation. PMID:27213689

  10. Naturally occurring Parelaphostrongylus tenuis-associated choriomeningitis in a guinea pig with neurologic signs.

    PubMed

    Southard, T; Bender, H; Wade, S E; Grunenwald, C; Gerhold, R W

    2013-05-01

    An adult male guinea pig (Cavia porcellus) with a 1-month history of hind limb paresis, torticollis, and seizures was euthanized and submitted for necropsy. Gross examination was unremarkable, but histologic examination revealed multifocal eosinophilic and lymphoplasmacytic choriomeningitis and cross sections of nematode parasites within the leptomeninges of the midbrain and diencephalon. Morphologic features of the nematode were consistent with a metastrongyle, and the parasite was identified as Parelaphostrongylus tenuis by polymerase chain reaction testing and nucleotide sequencing. Further questioning of the owner revealed that the guinea pig was fed grass from a yard often grazed by white-tailed deer (Odocoileus virginianus). To the authors' knowledge, this is the first report of a naturally occurring P. tenuis infection in a guinea pig.

  11. Effect of Naturally Occurring nif Reiterations on Symbiotic Effectiveness in Rhizobium phaseoli

    PubMed Central

    Romero, David; Singleton, Paul W.; Segovia, Lorenzo; Morett, Enrique; Bohlool, B. Ben; Palacios, Rafael; Dávila, Guillermo

    1988-01-01

    Most naturally occurring strains of Rhizobium phaseoli possess reiteration of the nif genes. Three regions contain nitrogenase structural genes in strain CFN42. Two of these regions (a and b) have copies of nifH, nifD, and nifK, whereas the third region (c) contains only nifH. Strains containing mutations in either nif region a or nif region b had significantly diminished symbiotic effectiveness compared with the wild-type strain on the basis of nodule mass, total nitrogenase activity per plant, nitrogenase specific activity, total nitrogen in the shoot, and percentage of nitrogen. A strain containing mutations in both nif region a and nif region b was totally ineffective. These data indicate that both nif region a and nif region b are needed for full symbiotic effectiveness in R. phaseoli. PMID:16347593

  12. Immunohistochemical detection of Brucella melitensis antigens in cases of naturally occurring abortions in sheep.

    PubMed

    Ilhan, Fatma; Yener, Zabit

    2008-11-01

    Brucella melitensis, a worldwide zoonotic pathogen, is a significant cause of abortion in sheep and goats in some countries. The present study was carried out to determine, by immunohistochemistry, the presence of B. melitensis antigens in 110 naturally occurring aborted sheep fetuses. Sections of lung, liver, kidney, and spleen of each fetus were stained with immunoperoxidase to detect Brucella antigens. Brucella melitensis antigens were detected in 33 of 110 fetuses (30%). In the 33 positive cases, Brucella antigens were found in lung (25 [22.7%]), liver (21 [19%]), spleen (13 [11.8%]), and kidney (6 [5.4%]). Microscopic studies demonstrated that Brucella antigens were mainly located in the cytoplasm of macrophages and neutrophils of the lung, and in the cytoplasm of macrophages in the portal infiltrates and Kupffer cells of the liver. It was concluded that immunohistochemistry in formalin-fixed, paraffin-embedded tissues is a useful tool for the diagnosis of spontaneous ovine abortion caused by B. melitensis.

  13. Characterization of naturally-occurring and modified fullerenes by Fourier transform mass spectrometry

    SciTech Connect

    Hettich, R.L.; Jin, C.; Compton, R.N. ); Buseck, P.R.; Tsipursky, S.J. )

    1993-10-10

    Fourier transform mass spectrometry (FTMS) employing both laser desorption/ionization and thermal desorption/electron ionization is useful for the detection and structural characterization of fullerenes and chemically-modified fullerenes. Examination of a carbon-rich shungite rock sample from Russia by transmission electron microscopy and FTMS provided evidence of naturally-occurring fullerenes. Ion-molecule reactions can be studied with FTMS to investigate the electron affinities of modified fullerenes. By monitoring charge exchange reactions, the electron affinities of C[sub 60]F[sub x] (x=44,46) and C[sub 70]F[sub y] (y=52,54) were found to be substantially higher than the values for the parent fullerenes.

  14. Biomimetic nitration of conjugated linoleic acid: formation and characterization of naturally occurring conjugated nitrodienes.

    PubMed

    Woodcock, Steven R; Salvatore, Sonia R; Bonacci, Gustavo; Schopfer, Francisco J; Freeman, Bruce A

    2014-01-03

    Nitro-conjugated linoleic acids (NO2-cLA), endogenous nitrodiene lipids which act as inflammatory signaling mediators, were isolated and single isomers purified from the biomimetic acidic nitration products of conjugated linoleic acid (CLA). Structures were elucidated by means of detailed NMR and HPLC-MS/MS spectroscopic analysis and the relative double bond configurations assigned. Additional synthetic methods produced useful quantities and similar isomeric distributions of these unusual and reactive compounds for biological studies and isotopic standards, and the potential conversion of nitro-linoleic to nitro-conjugated linoleic acids was explored via a facile base-catalyzed isomerization. This represents one of the few descriptions of naturally occurring conjugated nitro dienes (in particular, 1-nitro 1,3-diene), an unusual and highly reactive motif with few biological examples extant.

  15. Radon as a naturally occurring tracer for the assessment of residual NAPL contamination of aquifers.

    PubMed

    Schubert, Michael; Paschke, Albrecht; Lau, Steffen; Geyer, Wolfgang; Knöller, Kay

    2007-02-01

    The noble gas radon has a strong affinity to non-aqueous phase-liquids (NAPLs). That property makes it applicable as naturally occurring partitioning tracer for assessing residual NAPL contamination of aquifers. In a NAPL contaminated aquifer, radon dissolved in the groundwater partitions preferably into the NAPL. The magnitude of the resulting radon deficit in the groundwater depends on the NAPL-specific radon partition coefficient and on the NAPL saturation of the pore space. Hence, if the partition coefficient is known, the NAPL saturation is attainable by determination of the radon deficit. After a concise discussion of theoretical aspects regarding radon partitioning into NAPL, related experimental data and results of a field investigation are presented. Aim of the laboratory experiments was the determination of radon partition coefficients of multi-component NAPLs of environmental concern. The on-site activities were carried out in order to confirm the applicability of the "radon method" under field conditions.

  16. Naturally Occurring Nrf2 Activators: Potential in Treatment of Liver Injury

    PubMed Central

    2016-01-01

    Oxidative stress plays a major role in acute and chronic liver injury. In hepatocytes, oxidative stress frequently triggers antioxidant response by activating nuclear erythroid 2-related factor 2 (Nrf2), a transcription factor, which upregulates various cytoprotective genes. Thus, Nrf2 is considered a potential therapeutic target to halt liver injury. Several studies indicate that activation of Nrf2 signaling pathway ameliorates liver injury. The hepatoprotective potential of naturally occurring compounds has been investigated in various models of liver injuries. In this review, we comprehensively appraise various phytochemicals that have been assessed for their potential to halt acute and chronic liver injury by enhancing the activation of Nrf2 and have the potential for use in humans. PMID:28101296

  17. Effect of mangiferin, a naturally occurring glucoxylxanthone, on fear memory in rats.

    PubMed

    Andreu, Gilberto L Pardo; Maurmann, Natasha; Reolon, Gustavo Kellermann; de Farias, Caroline Brunetto; Delgado, René; Roesler, Rafael

    2011-01-01

    Mangiferin (1,3,6,7-tetrahydroxy-2-[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl] -xanthen-9-one, CAS 4773-96-0), a naturally occurring glucosylxanthone, is widely distributed in higher plants and a constituent of folk medicine. In the present study the effect of systemic administration of mangiferin on behavioural outcomes of neurological function in normal rats was investigated. A single intraperitoneal injection of mangiferin (10, 50 and 100 mg/kg body weight) immediately post-training produced an impairment of long-term memory for aversive training and a reduced freezing in a dose independent manner, when given immediately post-training. The administration of mangiferin 6 h post-training did not affect fear memory. The results indicate that mangiferin might induce deficits of emotionally motivated memory.

  18. Poly(anhydride-esters) Comprised Exclusively of Naturally Occurring Antimicrobials and EDTA: Antioxidant and Antibacterial Activities

    PubMed Central

    2015-01-01

    Carvacrol, thymol, and eugenol are naturally occurring phenolic compounds known to possess antimicrobial activity against a range of bacteria, as well as antioxidant activity. Biodegradable poly(anhydride-esters) composed of an ethylenediaminetetraacetic acid (EDTA) backbone and antimicrobial pendant groups (i.e., carvacrol, thymol, or eugenol) were synthesized via solution polymerization. The resulting polymers were characterized to confirm their chemical composition and understand their thermal properties and molecular weight. In vitro release studies demonstrated that polymer hydrolytic degradation was complete after 16 days, resulting in the release of free antimicrobials and EDTA. Antioxidant and antibacterial assays determined that polymer release media exhibited bioactivity similar to that of free compound, demonstrating that polymer incorporation and subsequent release had no effect on activity. These polymers completely degrade into components that are biologically relevant and have the capability to promote preservation of consumer products in the food and personal care industries via antimicrobial and antioxidant pathways. PMID:24702678

  19. Capillary zone electrophorsis for the analysis of naturally occurring 2-hydroxycitric acids and their lactones.

    PubMed

    Abhijith, B L; Mohan, Moolya; Joseph, David; Haleema, Simimole; Aboul-Enein, Hassan Y; Ibnusaud, Ibrahim

    2017-08-01

    A simple capillary zone electrophoresis method with direct ultraviolet detection has been developed for the analysis of naturally occurring diastereomeric 2-hydroxycitric acid lactones. Using 50 mM sodium phosphate buffer of pH 7, a baseline resolution Rs > 3.0 was observed for all organic acids selected for the present study. This method was employed for the quantitative determination of title acids present in the plant sources namely Garcinia cambogia fruit rinds and Hibiscus sabdariffa calyx. Conversion of 2-hydroxycitric acids to their lactones on heating the above plant sources is deliberated. The Hydrolysis of hydroxycitric acid lactones in aqueous solution is reported for the first time. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. A Naturally Occurring Antibody Fragment Neutralizes Infectivity of Diverse Infectious Agents

    PubMed Central

    Polonelli, Luciano; Ciociola, Tecla; Elviri, Lisa; Zanello, Pier Paolo; Giovati, Laura; Arruda, Denise C.; Muñoz, Julián E.; Mortara, Renato A.; Morace, Giulia; Borghi, Elisa; Galati, Serena; Marin, Oriano; Casoli, Claudio; Pilotti, Elisabetta; Ronzi, Paola; Travassos, Luiz R.; Magliani, Walter; Conti, Stefania

    2016-01-01

    A phosphorylated peptide, named K40H, derived from the constant region of IgMs was detected in human serum by liquid chromatography coupled to high-resolution mass spectrometry. Synthetic K40H proved to exert a potent in vitro activity against fungal pathogens, and to inhibit HIV-1 replication in vitro and ex vivo. It also showed a therapeutic effect against an experimental infection by Candida albicans in the invertebrate model Galleria mellonella. K40H represents the proof of concept of the innate role that naturally occurring antibody fragments may exert against infectious agents, shedding a new light upon the posthumous role of antibodies and opening a new scenario on the multifaceted functionality of humoral immunity. PMID:27725769

  1. Some Nutritional Characteristics of a Naturally Occurring Alga (Microcystis sp.) in a Guatemalan Lake

    PubMed Central

    de la Fuente, Gabriel; Flores, Antonio; Molina, Mario R.; Almengor, Leticia; Bressani, Ricardo

    1977-01-01

    The nutritional characteristics of an alga (Microcystis sp.) that occurs naturally in a Guatemalan lake were determined. The sun-dried material proved to have a high protein content (55.6%) and to be a possible good source of calcium and phosphorus (1, 169.1 and 633.4 mg/100 mg, respectively). Amino acid analysis showed that total sulfur amino acids were the most deficient ones, giving a protein score of 42 to the material. The in vitro protein digestibility of the material was 69.5%. Biological trials demonstrated that when the material was offered as the only protein source, very low consumption and a high mortality rate were obtained whether or not the diet was supplemented with 0.4% dl-methionine. However, when the material supplied 25% of the total protein of a corn-algae diet, the protein quality of the cereal was significantly improved (P < 0.05). PMID:16345191

  2. El Dorado Air Quality Management District's Approach to Dealing With Naturally Occurring Asbestos (NOA) Hazards

    NASA Astrophysics Data System (ADS)

    Thomas, C.

    2012-12-01

    In 2005, Naturally Occurring Asbestos (NOA) in El Dorado County made headlines with the discovery significant amounts of tremolite/actinolite asbestos in areas where residents had built, or were in the process of building, homes and residences. The El Dorado Air Quality Management District has been involved in all aspects of dealing with NOA from the very beginning of its discovery, from overseeing the rehabilitation of school sites to expanding and rewriting fugitive dust rules at construction sites. A discussion of best management practices which have been developed will be given, as well as how the El Dorado Air Quality Management District has worked to educate members of the public, as well as workers in the field, about NOA to aid in maintaining the health and safety of the public.

  3. Natural Competence of Xylella fastidiosa Occurs at a High Frequency Inside Microfluidic Chambers Mimicking the Bacterium's Natural Habitats

    PubMed Central

    Kandel, Prem P.; Lopez, Samantha M.; Almeida, Rodrigo P. P.

    2016-01-01

    ABSTRACT Xylella fastidiosa is a xylem-limited bacterium that is the causal agent of emerging diseases in a number of economically important crops. Genetic diversity studies have demonstrated homologous recombination occurring among X. fastidiosa strains, which has been proposed to contribute to host plant shifts. Moreover, experimental evidence confirmed that X. fastidiosa is naturally competent for recombination in vitro. Here, as an approximation of natural habitats (plant xylem vessels and insect mouthparts), recombination was studied in microfluidic chambers (MCs) filled with media amended with grapevine xylem sap. First, different media were screened for recombination in solid agar plates using a pair of X. fastidiosa strains that were previously reported to recombine in coculture. The highest frequency of recombination was obtained with PD3 medium, compared to those with the other two media (X. fastidiosa medium [XFM] and periwinkle wilt [PW] medium) used in previous studies. Dissection of the media components led to the identification of bovine serum albumin as an inhibitor of recombination that was correlated to its previously known effect on inhibition of twitching motility. When recombination was performed in liquid culture, the frequencies were significantly higher under flow conditions (MCs) than under batch conditions (test tubes). The recombination frequencies in MCs and agar plates were not significantly different from each other. Grapevine xylem sap from both susceptible and tolerant varieties allowed high recombination frequency in MCs when mixed with PD3. These results suggest that X. fastidiosa has the ability to be naturally competent in the natural growth environment of liquid flow, and this phenomenon could have implications in X. fastidiosa environmental adaptation. IMPORTANCE Xylella fastidiosa is a plant pathogen that lives inside xylem vessels (where water and nutrients are transported inside the plant) and the mouthparts of insect

  4. Evidence to suggest that cathepsin K degrades articular cartilage in naturally occurring equine osteoarthritis.

    PubMed

    Vinardell, T; Dejica, V; Poole, A R; Mort, J S; Richard, H; Laverty, S

    2009-03-01

    The mechanisms leading to degeneration of articular cartilage in osteoarthritis (OA) are complex and not yet fully understood. Cathepsin K (CK) is a cysteine protease which can also cleave the triple helix of type II collagen. This exposes a neoepitope that can now be identified by specific antibodies. The aim of this study was to obtain evidence suggesting a role for CK in naturally occurring equine OA in both lesional and peri-lesional regions. Articular cartilages (n=12 horses; 5 healthy, 7 OA) were harvested from animals postmortem. A gross macroscopic examination, histologic (Safranin O-Fast Green and Picrosirius red staining) and immunohistochemical evaluation were performed. Samples were divided into normal appearing cartilage, peri-lesional and lesional cartilage. Cartilage degradation in the samples was graded histologically and immunohistochemically. CK and possible CK cleavage were detected immunohistochemically with specific anti-protein and anti-neoepitope antibodies, respectively. A comparison of CK neoepitope (C2K) production with the collagenase-generated neoepitope produced by matrix metalloproteinases (MMP)-1, 8 and 13 (C2C) was also assessed immunohistochemically. CK and CK cleavage were significantly more abundant in OA cartilage (both peri-lesional and lesional) when compared to remote cartilage within the sample joint or cartilage from healthy joints. The immunohistochemical pattern observed for CK degradation (C2K) was similar to that of collagenase degradation (C2C). Macroscopic cartilage changes and histologic findings were significantly correlated with immunohistochemistry results. The data generated suggests that CK may be involved in cartilage collagen degradation in naturally occurring osteoarthritis.

  5. Characterization of Naturally-Occurring Humoral Immunity to AAV in Sheep

    PubMed Central

    Tellez, Joseph; Van Vliet, Kim; Tseng, Yu-Shan; Finn, Jonathan D.; Tschernia, Nick; Almeida-Porada, Graça; Arruda, Valder R.; Agbandje-McKenna, Mavis; Porada, Christopher D.

    2013-01-01

    AAV vectors have shown great promise for clinical gene therapy (GT), but pre-existing human immunity against the AAV capsid often limits transduction. Thus, testing promising AAV-based GT approaches in an animal model with similar pre-existing immunity could better predict clinical outcome. Sheep have long been used for basic biological and preclinical studies. Moreover, we have re-established a line of sheep with severe hemophilia A (HA). Given the impetus to use AAV-based GT to treat hemophilia, we characterized the pre-existing ovine humoral immunity to AAV. ELISA revealed naturally-occurring antibodies to AAV1, AAV2, AAV5, AAV6, AAV8, and AAV9. For AAV2, AAV8, and AAV9 these inhibit transduction in a luciferase-based neutralization assay. Epitope mapping identified peptides that were common to the capsids of all AAV serotypes tested (AAV2, AAV5, AAV8 and AAV9), with each animal harboring antibodies to unique and common capsid epitopes. Mapping using X-ray crystallographic AAV capsid structures demonstrated that these antibodies recognized both surface epitopes and epitopes located within regions of the capsid that are internal or buried in the capsid structure. These results suggest that sheep harbor endogenous AAV, which induces immunity to both intact capsid and to capsid epitopes presented following proteolysis during the course of infection. In conclusion, their clinically relevant physiology and the presence of naturally-occurring antibodies to multiple AAV serotypes collectively make sheep a unique model in which to study GT for HA, and other diseases, and develop strategies to circumvent the clinically important barrier of pre-existing AAV immunity. PMID:24086458

  6. Risk and protective factors for cats with naturally occurring chronic kidney disease.

    PubMed

    Piyarungsri, Kakanang; Pusoonthornthum, Rosama

    2017-04-01

    Objectives Chronic kidney disease (CKD) is a significant disease in cats. Identifying risk and protective factors may help to prevent this significant disease. Methods An age-matched case-control study was performed to determine the risk factors in cats with naturally occurring CKD. Twenty-nine clinically normal cats aged ⩾5 years and 101 cats with naturally occurring CKD were studied. Risk factors were determined by interviewing cat owners from the Small Animal Hospital, Faculty of Veterinary Science, Chulalongkorn University, and veterinary hospitals in the Bangkok Metropolitan area, through questionnaires completed between June 2004 and November 2014. Univariable and multivariable analyses were performed using two independent proportional test methods and logistic regression analysis with backward elimination. Results Male sex (odd ratios [OR] 2.80, 95% confidence interval [CI] 1.02-8.87; P = 0.02), tap water (OR 3.43, 95% CI 1.08-11.45; P = 0.03) and an outdoor lifestyle (OR 3.77, 95% CI 1.03-17.99; P = 0.04) were associated with an increased risk for CKD. Commercial dry cat food (OR 0.06, 95% CI 0.02-0.17; P = 0.00), filtered water (OR 0.13, 95% CI 0.03-0.52; P = 0.01) and an indoor lifestyle (OR 0.28, 95% CI 0.07-0.98; P = 0.02) were associated with a decreased risk. Logistic regression analysis using backward elimination demonstrated that cats fed commercial dry cat food (OR 0.042, 95% CI 0.01-0.17; P = 0.00) had a decreased risk for CKD compared with cats on other types of diet. Conclusions and relevance Multivariable analysis found only feeding commercial dry cat food to be significant, suggesting that commercial dry cat food may be a potential protective factor for CKD in cats.

  7. Biased Signaling in Naturally Occurring Mutations in Human Melanocortin-3 Receptor Gene

    PubMed Central

    Yang, Fan; Huang, Hui; Tao, Ya-Xiong

    2015-01-01

    The melanocortin-3 receptor (MC3R) is primarily expressed in the hypothalamus and plays an important role in the regulation of energy homeostasis. Recently, some studies demonstrated that MC3R also signals through mitogen-activated protein kinases (MAPKs), especially extracellular signal-regulated kinases 1 and 2 (ERK1/2). ERK1/2 signaling is known to alter gene expression, potentially contributing to the prolonged action of melanocortins on energy homeostasis regulation. In the present study, we performed detailed functional studies on 8 novel naturally occurring MC3R mutations recently reported, and the effects of endogenous MC3R agonist, α-melanocyte stimulating hormone (MSH), on ERK1/2 signaling on all 22 naturally occurring MC3R mutations reported to date. We found that mutants D158Y and L299V were potential pathogenic causes to obesity. Four residues, F82, D158, L249 and L299, played critical roles in different aspects of MC3R function. α-MSH exhibited balanced activity in Gs-cAMP and ERK1/2 signaling pathways in 15 of the 22 mutant MC3Rs. The other 7 mutant MC3Rs were biased to either one of the signaling pathways. In summary, we provided novel data about the structure-function relationship of MC3R, identifying residues important for receptor function. We also demonstrated that some mutations exhibited biased signaling, preferentially activating one intracellular signaling pathway, adding a new layer of complexity to MC3R pharmacology. PMID:25798062

  8. Behavioral changes in freestall-housed dairy cows with naturally occurring clinical mastitis.

    PubMed

    Fogsgaard, K K; Bennedsgaard, T W; Herskin, M S

    2015-03-01

    Dairy cows exhibit classic signs of sickness behavior during mastitis. However, knowledge about the consequences of naturally occurring mastitis in freestall-housed dairy cows, milked in automatic milking systems, is lacking. The aim of the present study was to describe the behavior of dairy cows after diagnosis and antibiotic treatment of mastitis. In the days before and after antibiotic treatment, the milking behavior, feeding, and activity were examined in 30 mastitic and 30 control Danish Holstein-Friesian cows kept in freestalls and milked by an automatic milking system. Sickness behavior was evident in the mastitic dairy cows and local clinical signs in the udder as well as behavioral changes persisted beyond the 3 d of antibiotic treatment. In the days before diagnosis and treatment, feed intake was reduced compared with the control animals. Although reduced by the antibiotic treatment, this difference persisted until at least 10 d after diagnosis. Sick cows spent less time lying in the initial days after treatment, reversing to the level of the control cows within the 10 d posttreatment period. In the 48 h before antibiotic treatment, the mastitic cows showed increased restlessness during milking, as seen by a higher frequency of tripping and kicking. Mastitic cows continued to show increased kicking during milking even after the antibiotic treatment period. These results show that the behavioral changes induced by naturally occurring mastitis persisted beyond the days of antibiotic treatment, thereby calling for further investigation into management of mastitic dairy cows to optimize recovery and ensure animal welfare during the recovery period after clinical mastitis.

  9. Naturally occurring radioactive material (NORM) from a former phosphoric acid processing plant.

    PubMed

    Beddow, H; Black, S; Read, D

    2006-01-01

    In recent years there has been an increasing awareness of the radiological impact of non-nuclear industries that extract and/or process ores and minerals containing naturally occurring radioactive material (NORM). These industrial activities may result in significant radioactive contamination of (by-) products, wastes and plant installations. In this study, scale samples were collected from a decommissioned phosphoric acid processing plant. To determine the nature and concentration of NORM retained in pipe-work and associated process plant, four main areas of the site were investigated: (1) the 'Green Acid Plant', where crude acid was concentrated; (2) the green acid storage tanks; (3) the Purified White Acid (PWA) plant, where inorganic impurities were removed; and (4) the solid waste, disposed of on-site as landfill. The scale samples predominantly comprise the following: fluorides (e.g. ralstonite); calcium sulphate (e.g. gypsum); and an assemblage of mixed fluorides and phosphates (e.g. iron fluoride hydrate, calcium phosphate), respectively. The radioactive inventory is dominated by 238U and its decay chain products, and significant fractionation along the series occurs. Compared to the feedstock ore, elevated concentrations (< or =8.8 Bq/g) of 238U were found to be retained in installations where the process stream was rich in fluorides and phosphates. In addition, enriched levels (< or =11 Bq/g) of 226Ra were found in association with precipitates of calcium sulphate. Water extraction tests indicate that many of the scales and waste contain significantly soluble materials and readily release radioactivity into solution.

  10. Characterization of naturally-occurring humoral immunity to AAV in sheep.

    PubMed

    Tellez, Joseph; Van Vliet, Kim; Tseng, Yu-Shan; Finn, Jonathan D; Tschernia, Nick; Almeida-Porada, Graça; Arruda, Valder R; Agbandje-McKenna, Mavis; Porada, Christopher D

    2013-01-01

    AAV vectors have shown great promise for clinical gene therapy (GT), but pre-existing human immunity against the AAV capsid often limits transduction. Thus, testing promising AAV-based GT approaches in an animal model with similar pre-existing immunity could better predict clinical outcome. Sheep have long been used for basic biological and preclinical studies. Moreover, we have re-established a line of sheep with severe hemophilia A (HA). Given the impetus to use AAV-based GT to treat hemophilia, we characterized the pre-existing ovine humoral immunity to AAV. ELISA revealed naturally-occurring antibodies to AAV1, AAV2, AAV5, AAV6, AAV8, and AAV9. For AAV2, AAV8, and AAV9 these inhibit transduction in a luciferase-based neutralization assay. Epitope mapping identified peptides that were common to the capsids of all AAV serotypes tested (AAV2, AAV5, AAV8 and AAV9), with each animal harboring antibodies to unique and common capsid epitopes. Mapping using X-ray crystallographic AAV capsid structures demonstrated that these antibodies recognized both surface epitopes and epitopes located within regions of the capsid that are internal or buried in the capsid structure. These results suggest that sheep harbor endogenous AAV, which induces immunity to both intact capsid and to capsid epitopes presented following proteolysis during the course of infection. In conclusion, their clinically relevant physiology and the presence of naturally-occurring antibodies to multiple AAV serotypes collectively make sheep a unique model in which to study GT for HA, and other diseases, and develop strategies to circumvent the clinically important barrier of pre-existing AAV immunity.

  11. Making species salinity sensitivity distributions reflective of naturally occurring communities: using rapid testing and Bayesian statistics.

    PubMed

    Hickey, Graeme L; Kefford, Ben J; Dunlop, Jason E; Craig, Peter S

    2008-11-01

    Species sensitivity distributions (SSDs) may accurately predict the proportion of species in a community that are at hazard from environmental contaminants only if they contain sensitivity data from a large sample of species representative of the mix of species present in the locality or habitat of interest. With current widely accepted ecotoxicological methods, however, this rarely occurs. Two recent suggestions address this problem. First, use rapid toxicity tests, which are less rigorous than conventional tests, to approximate experimentally the sensitivity of many species quickly and in approximate proportion to naturally occurring communities. Second, use expert judgements regarding the sensitivity of higher taxonomic groups (e.g., orders) and Bayesian statistical methods to construct SSDs that reflect the richness (or perceived importance) of these groups. Here, we describe and analyze several models from a Bayesian perspective to construct SSDs from data derived using rapid toxicity testing, combining both rapid test data and expert opinion. We compare these new models with two frequentist approaches, Kaplan-Meier and a log-normal distribution, using a large data set on the salinity sensitivity of freshwater macroinvertebrates from Victoria (Australia). The frequentist log-normal analysis produced a SSD that overestimated the hazard to species relative to the Kaplan-Meier and Bayesian analyses. Of the Bayesian analyses investigated, the introduction of a weighting factor to account for the richness (or importance) of taxonomic groups influenced the calculated hazard to species. Furthermore, Bayesian methods allowed us to determine credible intervals representing SSD uncertainty. We recommend that rapid tests, expert judgements, and novel Bayesian statistical methods be used so that SSDs reflect communities of organisms found in nature.

  12. Computational Assessment of Naturally Occurring Neutron and Photon Background Radiation Produced by Extraterrestrial Sources

    DOE PAGES

    Miller, Thomas Martin; de Wet, Wouter C.; Patton, Bruce W.

    2015-10-28

    In this study, a computational assessment of the variation in terrestrial neutron and photon background from extraterrestrial sources is presented. The motivation of this assessment is to evaluate the practicality of developing a tool or database to estimate background in real time (or near–real time) during an experimental measurement or to even predict the background for future measurements. The extraterrestrial source focused on during this assessment is naturally occurring galactic cosmic rays (GCRs). The MCNP6 transport code was used to perform the computational assessment. However, the GCR source available in MCNP6 was not used. Rather, models developed and maintained bymore » NASA were used to generate the GCR sources. The largest variation in both neutron and photon background spectra was found to be caused by changes in elevation on Earth's surface, which can be as large as an order of magnitude. All other perturbations produced background variations on the order of a factor of 3 or less. The most interesting finding was that ~80% and 50% of terrestrial background neutrons and photons, respectively, are generated by interactions in Earth's surface and other naturally occurring and man-made objects near a detector of particles from extraterrestrial sources and their progeny created in Earth's atmosphere. In conclusion, this assessment shows that it will be difficult to estimate the terrestrial background from extraterrestrial sources without a good understanding of a detector's surroundings. Therefore, estimating or predicting background during a measurement environment like a mobile random search will be difficult.« less

  13. Naturally occurring circadian rhythm and sleep duration are related to executive functions in early adulthood.

    PubMed

    Kuula, Liisa; Pesonen, Anu-Katriina; Heinonen, Kati; Kajantie, Eero; Eriksson, Johan Gunnar; Andersson, Sture; Lano, Aulikki; Lahti, Jari; Wolke, Dieter; Räikkönen, Katri

    2017-07-20

    Experimental sleep deprivation studies suggest that insufficient sleep and circadian misalignment associates with poorer executive function. It is not known whether this association translates to naturally occurring sleep patterns. A total of 512 of full-term-born members of the Arvo Ylppö Longitudinal Study [mean age = 25.3, standard deviation (SD) = 0.65] (44.3% men) wore actigraphs to define sleep duration, its irregularity and circadian rhythm (sleep mid-point) during a 1-week period (mean 6.9 nights, SD = 1.7). Performance-based executive function was assessed with the Trail-Making Test, Conners' Continuous Performance Test and Stroop. The self-rated adult version of Behavior Rating Inventory of Executive Function was used to assess trait-like executive function. We found that performance-based and self-reported trait-like executive function correlated only modestly (all correlations ≤0.17). Shorter sleep duration associated with more commission errors. Later circadian rhythm associated with poorer trait-like executive function, as indicated by the Brief Metacognitive Index and the Behavior Regulation Index. Those belonging to the group with the most irregular sleep duration performed slower than others in the Trail-Making Test Part A. All associations were adjusted for sex, age, socioeconomic status and body mass index. In conclusion, naturally occurring insufficient sleep and later circadian rhythm showed modest associations with poorer executive function. Shorter habitual sleep duration was associated with lower scores of performance-based tests of executive function, and later circadian rhythm was associated mainly with poorer trait-like executive function characteristics. Our findings suggest additionally that sleep duration and circadian rhythm associate with different domains of executive function, and there are no additive effects between the two. © 2017 European Sleep Research Society.

  14. Naturally occurring MHR variants in Turkish patients infected with hepatitis B virus.

    PubMed

    Sayiner, A Arzu; Ozcan, Ayla; Sengonul, Aylin

    2008-03-01

    Major B-cell epitopes are located at the major hydrophilic region (MHR) of hepatitis B virus (HBV) surface antigen (HBsAg). The genotypes, subtypes, and naturally occurring amino acid (aa) substitutions of MHR were analyzed in 81 Turkish adult patients (41 inactive HBsAg carriers and 40 patients with chronic hepatitis B) by direct sequencing of the S gene fragment. All the isolates were genotype D according to the phylogenetic analysis. The most common HBsAg subtype was ayw2, followed by ayw3 while one isolate specified ayw4 by encoding Leu127. MHR variants were detected in 22 of the 81 (27.2%) isolates. The prevalence was significantly higher in the chronic hepatitis B group (42.5%) compared to inactive HBsAg carriers (12.2%). Twenty-two samples had a total of 26 amino acid substitutions involving 14 positions. The majority of the patients had a single variation. Most of the amino acid substitutions were located at the HBs1 region of the MHR, while 9 of the 26 were in the classic "a" determinant (aa 124-147). When samples with "a" variants were evaluated by two different commercial HBsAg tests, only the isolate with Ser143Leu variation had a decreased reactivity in the assay using monoclonal antibodies for capture and detection. In conclusion, the findings of the study was in accordance with previous studies showing HBV genotype and subtype homogeneity (genotype D/ayw) in Turkey. Naturally occurring MHR and "a" determinant variants were common, especially among chronic hepatitis B patients. The influence of detected "a" variants on diagnostic assays was limited.

  15. Naturally occurring marine brominated indoles are aryl hydrocarbon receptor ligands/agonists.

    PubMed

    DeGroot, Danica E; Franks, Diana G; Higa, Tatsuo; Tanaka, Junichi; Hahn, Mark E; Denison, Michael S

    2015-06-15

    The aryl hydrocarbon receptor (AhR) is a ligand-dependent transcription factor that mediates the toxic and biological effects of structurally diverse chemicals, including the environmental contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). As part of a larger effort to identify the full spectrum of chemicals that can bind to and activate the AhR, we have examined the ability of several naturally occurring marine-derived brominated indoles and brominated (methylthio)indoles (collectively referred to as brominated indoles) to bind to the AhR and stimulate AhR-dependent gene expression. Incubation of mouse, rat, and guinea pig recombinant cell lines containing a stably transfected AhR-responsive luciferase reporter gene with eight brominated indoles revealed that all compounds stimulated luciferase reporter gene activity, although some species-specific differences were observed. All compounds induced significantly more luciferase activity when incubated with cells for 4 h as compared to 24 h, demonstrating that these compounds are transient activators of the AhR signaling pathway. Three of the brominated indoles induced CYP1A1 mRNA in human HepG2 cells in vitro and Cyp1a mRNA in zebrafish embryos in vivo. The identification of the brominated indoles as direct ligands and activators/agonists of the AhR was confirmed by their ability to compete with [(3)H]TCDD for binding to the AhR and to stimulate AhR transformation and DNA binding in vitro. Taken together, these results indicate that marine-derived brominated indoles are members of a new class of naturally occurring AhR agonists.

  16. Naturally-Occurring Marine Brominated Indoles are Aryl Hydrocarbon Receptor Ligands/Agonists

    PubMed Central

    DeGroot, Danica E.; Franks, Diana G.; Higa, Tatsuo; Tanaka, Junichi; Hahn, Mark E.; Denison, Michael S.

    2015-01-01

    The aryl hydrocarbon receptor (AhR) is a ligand-dependent transcription factor that mediates the toxic and biological effects of structurally diverse chemicals, including the environmental contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). As part of a larger effort to identify the full spectrum of chemicals that can bind to and activate the AhR, we have examined the ability of several naturally-occurring marine-derived brominated indoles and brominated (methylthio)indoles (collectively referred to as “brominated indoles”) to bind to the AhR and stimulate AhR-dependent gene expression. Incubation of mouse, rat and guinea pig recombinant cell lines containing a stably transfected AhR-responsive luciferase reporter gene with eight brominated indoles revealed that all compounds stimulated luciferase reporter gene activity, although some species-specific differences were observed. All compounds induced significantly more luciferase activity when incubated with cells for 4 h as compared to 24 h, demonstrating that these compounds are transient activators of the AhR signaling pathway. Three of the brominated indoles induced CYP1A1 mRNA in human HepG2 cells in vitro and Cyp1a mRNA in zebrafish embryos in vivo. The identification of the brominated indoles as direct ligands and activators/agonists of the AhR was confirmed by their ability to compete with [3H]TCDD for binding to the AhR and to stimulate AhR transformation and DNA binding in vitro. Taken together, these marine-derived brominated indoles are members of a new class of naturally-occurring AhR agonists. PMID:26001051

  17. Urinary bladder cancer in dogs, a naturally occurring model for cancer biology and drug development.

    PubMed

    Knapp, Deborah W; Ramos-Vara, José A; Moore, George E; Dhawan, Deepika; Bonney, Patty L; Young, Kirsten E

    2014-01-01

    Each year more than 65,000 people are diagnosed with urinary bladder cancer, and more than 14,000 people die from the disease in the United States. Studies in relevant animal models are essential to improve the management of bladder cancer. Naturally occurring bladder cancer in dogs very closely mimics human invasive bladder cancer, specifically high-grade invasive transitional cell carcinoma (TCC; also referred to as invasive urothelial carcinoma) in cellular and molecular features; biological behavior, including sites and frequency of metastasis; and response to therapy. Canine bladder cancer complements experimentally induced rodent tumors in regard to animal models of bladder cancer. Results of cellular and molecular studies and -omics analyses in dogs are expected to lead to improved detection of TCC and preneoplastic lesions, earlier intervention, better prediction of patient outcome, and more effective TCC management overall. Studies in dogs are being used to help define heritable risks (through very strong breed-associated risk) and environment risks and to evaluate prevention and treatment approaches that benefit humans as well as dogs. Clinical treatment trials in pet dogs with TCC are considered a win-win scenario by clinician scientists and pet owners. The individual dog benefits from effective treatment, the results are expected to help other dogs, and the findings are expected to ultimately help humans with TCC. This article provides an overview of canine TCC, a summary of the similarities and differences between canine and human invasive TCC, and examples of the types of valuable translational research that can be done using dogs with naturally occurring TCC.

  18. Naturally Occurring Asbestos in the Southern Nevada Region: Potential for Human Exposure

    NASA Astrophysics Data System (ADS)

    Buck, B. J.; Metcalf, R. V.; Berry, D.; McLaurin, B.; Kent, D.; Januch, J.; Goossens, D.

    2015-12-01

    Naturally occurring fibrous actinolite, winchite, magnesioriebeckite, richterite, magnesiohornblende, and erionite have been found in rock, soil, and dust in southern Nevada and northwestern Arizona. The areas containing naturally occurring asbestos (NOA) include urban areas (e.g. Boulder City) and rural areas where people routinely enjoy outdoor activities including horseback riding, running, hiking, bicycling, and off-road-vehicle (ORV) recreation. A recent study showing mesothelioma in young people and women suggests some form of environmental exposure. Rock, soil, dust and clothing were analyzed using scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS); additional rock samples were analyzed using wavelength dispersive electron probe microanalysis (EPMA); additional soil samples were analyzed using PLM (polarizing light microscopy) and TEM (transmission electron microscopy) using the Fluidized Bed Asbestos Segregator preparation method. Winds have transported and mixed the Ca-amphiboles, which are primarily from Nevada, with the Na-amphiboles that are primarily from northwestern Arizona. Erionite, which has not previously been reported in this area, was a common soil component found in 5 of 6 samples. The erionite source has not yet been determined. Winds have transported the amphibole and erionite particles into the Nellis Dunes Recreation Area - an ORV recreation area located 35 km north of Boulder City that otherwise would not be geologically predicted to contain fibrous amphiboles. In Boulder City, wind directions are primarily bimodal N-NE and S-SW with the strongest winds in the spring coming from the S-SW. The arid climate in this part of the Mojave Desert greatly increases the potential for wind erosion and human exposures. These results suggest that the entire Las Vegas Basin has, at times, received these particles through wind transport. Because the most likely human exposure pathway is through inhalation of dust, the Las Vegas

  19. Naturally occurring neuronal plasticity in visual wulst of the Baya weaver, Ploceus philippinus (Linnaeus, 1766).

    PubMed

    Srivastava, U C; Gaur, Parul

    2013-06-01

    The visual wulst (VW), the rostro-dorsal surface of the avian telencephalon extending from the midline to the lateral region of the brain, is a laminated "bulge" consisting in four histologically distinct rostro-caudally arranged laminae with a specific sequence: hyperpallium apicale, interstitial nucleus of hyperpallium apicale, hyperpallium intercalatum and hyperpallium densocellulare. The VW has been proposed to be the avian equivalent of the mammalian striate cortex. Various behavioral studies including lesion experiments have indicated the importance of the VW, which receives visual and/or auditory cues. We have investigated qualitatively and quantitatively the fascinating structural changes occurring in VW neurons of the seasonally breeding bird, Ploceus philippinus (Linnaeus, 1766). The Golgi method was used to study the seasonal fluctuations in the neuronal classes of the VW with regard to dendritic thickness, spine morphology and spine density during both the non-breeding and breeding periods of male Baya weaver birds. Significant variations in parameters studied among the various neuronal types located in the different well-demarcated regions of the VW are believed to contribute to the functional differences reported among the wulst regions. Thus, this study extends our view demonstrating naturally occurring neuronal plasticity in a seasonally dynamic avian brain of a bird that hones not only its learning and memorizing system but also its social and sexual system in preparation for the breeding season.

  20. In vitro conversion of vinyl to formyl groups in naturally occurring chlorophylls.

    PubMed

    Loughlin, Patrick C; Willows, Robert D; Chen, Min

    2014-08-14

    The chemical structural differences distinguishing chlorophylls in oxygenic photosynthetic organisms are either formyl substitution (chlorophyll b, d, and f) or the degree of unsaturation (8-vinyl chlorophyll a and b) of a side chain of the macrocycle compared with chlorophyll a. We conducted an investigation of the conversion of vinyl to formyl groups among naturally occurring chlorophylls. We demonstrated the in vitro oxidative cleavage of vinyl side groups to yield formyl groups through the aid of a thiol-containing compound in aqueous reaction mixture at room temperature. Heme is required as a catalyst in aqueous solution but is not required in methanolic reaction mixture. The conversion of vinyl- to formyl- groups is independent of their position on the macrocycle, as we observed oxidative cleavages of both 3-vinyl and 8-vinyl side chains to yield formyl groups. Three new chlorophyll derivatives were synthesised using 8-vinyl chlorophyll a as substrate: 8-vinyl chlorophyll d, [8-formyl]-chlorophyll a, and [3,8-diformyl]-chlorophyll a. The structural and spectral properties will provide a signature that may aid in identification of the novel chlorophyll derivatives in natural systems. The ease of conversion of vinyl- to formyl- in chlorophylls demonstrated here has implications regarding the biosynthetic mechanism of chlorophyll d in vivo.

  1. Aberrant wound healing in the horse: naturally occurring conditions reminiscent of those observed in man.

    PubMed

    Theoret, Christine L; Wilmink, Jacintha M

    2013-01-01

    Impaired wound healing represents an enormous clinical and financial problem for companion animals and humans alike. Unfortunately, most models used to study healing rely on rodents, which have significant differences in the healing and scarring process and rarely develop complications. In order to better simulate impaired healing, the model should strive to reproduce the natural processes of healing and delayed healing. Wounds on the limbs of horses display similarities to wounds in humans in their epithelialization/contraction ratio, genetic influence as well as dysregulated cytokine profile and the spontaneous development of fibroproliferative disorders. Veterinarians have access to advanced wound therapies that are often identical to those provided to human patients. Wound research in large animals has resulted in new wound models as well as a better understanding of the physiology, immunology, and local environmental impact on both normal and aberrant wound healing. One such model reproduces the naturally occurring fibroproliferative disorder of horses known as exuberant granulation tissue. Comparisons between the normally healing and impaired wounds provide insight into the repair process and can facilitate product development. A better understanding of the wound healing physiopathology based on clinically accurate animal models should lead to the development of novel therapies thereby improving outcomes in both human and veterinary patients. © 2013 by the Wound Healing Society.

  2. Identification of naturally occurring hybrids between two overexploited sciaenid species along the South African coast.

    PubMed

    Mirimin, L; Kerwath, S E; Macey, B M; Bester-van der Merwe, A E; Lamberth, S J; Bloomer, P; Roodt-Wilding, R

    2014-07-01

    Hybridisation between fish species can play a significant role in evolutionary processes and can influence management and conservation planning, however, this phenomenon has been widely understudied, especially in marine organisms. The distribution limits of two sciaenid species (silver kob, Argyrosomus inodorus, and dusky kob, A. japonicus) partly overlap along the South African coast, where both species have undergone severe depletion due to overfishing. Following the identification of a number of possible cases of species misidentification or hybridisation (21 out of 422 individuals), nuclear and mitochondrial DNA data (12microsatellite loci and 562bp of the COI gene) were analysed to investigate the genetic composition of these individuals. Results indicated a field-based species misidentification rate of approximately 2.8% and a rate of natural hybridisation of 0.7%. Interestingly, all hybrid fish resulted from first-generation (F1) hybridisation events, which occurred exclusively between silver kob females and dusky kob males. Whether hybridisation is the result of natural events (such as secondary contact following a shift in distribution range), or anthropogenic activities (size-selective pressure due to overfishing), these findings have important implications for critical recovery and future management of these species in the wild.

  3. The membrane integration of a naturally occurring alpha-helical hairpin.

    PubMed

    Nagy, Akos; Turner, R James

    2007-05-04

    Helical hairpins, two closely spaced helical membrane spanning segments separated by a short surface turn, are thought to be common in integral membrane proteins. Here, we study the membrane integration of a naturally occurring helical hairpin from the secretory Na(+)-K(+)-2Cl(-) cotransporter NKCC1. This sequence is only slightly longer and significantly less hydrophobic than a previously identified minimal poly-leucine model hairpin structure. Using site directed mutagenesis we document the importance of the turn propensity of the amino acids in the intervening surface turn but, somewhat surprisingly, our results indicate that the formation of this natural hairpin apparently does not depend on specific helix-helix interactions. Our results suggest that helical hairpins may be formed quite readily from even minimally hydrophobic sequences separated by a short, sufficiently strong, turn signal, and that current methods for predicting integral membrane protein topology may miss many similar short helical hairpin sequences. Thus the occurrence of these structures may be much more common than presently thought.

  4. From naturally-occurring neurotoxic agents to CNS shuttles for drug delivery.

    PubMed

    Soddu, Elena; Rassu, Giovanna; Giunchedi, Paolo; Sarmento, Bruno; Gavini, Elisabetta

    2015-07-10

    Central nervous system (CNS) diseases are hard to diagnose and therapeutically target due to the blood brain barrier (BBB), which prevents most drugs from reaching their sites of action within the CNS. Brain drug delivery systems were conceived to bypass the BBB and were derived from anatomical and functional analysis of the BBB; this analysis led researchers to take advantage of brain endothelial membrane physiology to allow drug access across the BBB. Both receptors and carriers can be used to transport endogenous and exogenous substances into the CNS. Combining a drug with substances that take advantage of these internalization mechanisms is a widely exploited strategy for drug delivery because it is an indirect method that overcomes the BBB in a non-invasive way and is therefore less dangerous and costly than invasive methods. Neurotoxins, among other naturally-occurring substances, may be used as drug carriers to specifically target the CNS. This review covers the current delivery systems that take advantage of the non-toxic components of neurotoxins to overcome the BBB and reach the CNS. We hope to give insights to researchers toward developing new delivery systems that exploit the positive features of substances usually regarded as natural hazards.

  5. Naturally occurring PDGF receptor inhibitors with potential anti-atherosclerotic properties.

    PubMed

    Ricci, Chiara; Ferri, Nicola

    2015-07-01

    Platelet-derived growth factor (PDGF) represents one of the most prominent inducer of smooth muscle cell (SMC) migration and proliferation. Homo- and heterodimers of PDGF-A, PDGF-B, PDGF-C and PDGF-D subunits act by binding to homo- or heterodimers of the PDGF tyrosine kinase receptors, PDGFR-α and PDGFR-β. The essential role of PDGFR signaling on restenosis post-angioplasty or atherosclerosis has been demonstrated by using blocking antibodies to PDGF or the tyrosine kinase inhibitor imatinib. More specifically, molecular studies have defined the intracellular signaling pathways activated by PDGF, inducing the cell cycle progression and the migration of SMCs. Considering the relevant role of PDGF in atherogenesis, several studies have been performed to investigate the effect of naturally occurring compounds on both in vitro and in vivo experimental models of atherogenesis. The present review will briefly summarize the pathophysiological role of PDGF and the studies of natural inhibitors tested in in vivo experimental models of restenosis in response to vascular injury and/or atherosclerosis.

  6. Phosphate removal from wastewaters by a naturally occurring, calcium-rich sepiolite.

    PubMed

    Yin, Hongbin; Yun, Ye; Zhang, Yinlong; Fan, Chengxin

    2011-12-30

    Developing an easily handled and cost-effective phosphate absorbent is crucial for the control of water eutrophication. In this study, a naturally occurring, calcium-rich sepiolite (NOCS) was evaluated for its feasibility as a phosphate absorbent candidate. Batch studies showed that phosphate sorption on NOCS followed a stepwise isotherm for concentrations between 5 and 1000 mg P/l, and the phosphate sorption was fitted well by the Freundlich equation. The estimated maximum phosphorus sorption capacity was 32.0 mg P/g, which was quite high compared with other natural materials and was comparable to some efficient manmade P absorbents. The NOCS sorption kinetics followed a pseudo-first-order model with an R(2) value of 0.999. The adsorption of phosphate was highly pH dependent. Phosphate adsorption decreased moderately with increasing pH values from 3.0 to 6.0, and it decreased sharply in alkaline conditions. Ionic strength, sulfate, nitrate and chloride anions had no effects on the phosphate removal capacity of NOCS, but fluoride and bicarbonate anions exerted large effects. Phosphorus fractionation indicated that phosphate removed from the solution was primarily formed as a calcium-bound phosphorus precipitation, which was further confirmed by SEM-EDS analysis. Moreover, phosphate was barely (<1.5%) desorbed from the phosphorus-adsorbed sepiolite regardless of pH value. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Naturally occurring double-stranded RNA and immune responses. III. Immunogenicity and antigenicity in animals.

    PubMed Central

    Cunningham, P G; Naysmith, J D

    1975-01-01

    Naturally occurring, double-stranded RNA (ds-RNA)) was immunogenic when injected into mice, rats, guinea-pigs, rabbits, dogs and baboons. The response to native material administered intravenously (i.v.) was strongest in rabbits and mice, and weakest in baboons. Mice, guinea-pigs and baboons injected with ds-RNA complexed with methylated BSA emulsified in Freund's complete adjuvant all gave high antibody responses. When ds-RNA was given in aerosol form to mice and guinea-pigs the response was weaker than that following i.v. injection, and baboons did not respond to antigen given as an aerosol. In most species the immune response obtained was predominantly IgM in nature, and there was no evidence for cell-mediated immunity in any species. The only evidence of an adverse reaction associated with repeated administration of ds-RNA was a systemic anaphylactic-type response in a small group of mice given ds-RNA repeatedly in aerosol form and challenged with ds-RNA i.v. PMID:811555

  8. Allelopathic properties of α-terthienyl and phenylheptatriyne, naturally occurring compounds from species of asteraceae.

    PubMed

    Campbell, G; Lambert, J D; Arnason, T; Towers, G H

    1982-06-01

    Alpha-terthienyl (α-T), a naturally occurring polyacetylene derivative from roots ofTagetes erecta L., and phenylheptatriyne (PHT), from leaves ofBidens pilosa L., were tested as possible allelopathic agents against four seedling species (Asclepias syriaca L.,Chenopodium album L.,Phleum pratense L.,Trifolium pratense L.).Asclepias was the most sensitive of the species. Allelopathic activity was enhanced in the presence of sunlight or sources of near-UV, with LC50s forA. syriaca of 0.15 ppm and 0.66 ppm with α-T and PHT, respectively; 0.27 and 0.85 forC. album; 0.79 and 1.43 forP. pratense, and 1.93 and 1.82 forT. pratense. Near-UV exposure was saturating but never more than found in summer sunlight at Ottawa, Canada. Growth inhibition was observed with seedlings treated with α-T and PHT but without near-UV irradiation. Germination of seedlings was also sensitive to α-T and PHT with or without near-UV treatment. α-T was extracted from soil surrounding the roots ofTagetes. Concentrations calculated for the soil (0.4 ppm) indicate that seedling growth could be significantly hindered. The activity and specificity of α-T was sufficiently high to warrant future field trials to assess its potential as a natural weed-control agent.

  9. In vitro Conversion of Vinyl to Formyl Groups in Naturally Occurring Chlorophylls

    PubMed Central

    Loughlin, Patrick C.; Willows, Robert D.; Chen, Min

    2014-01-01

    The chemical structural differences distinguishing chlorophylls in oxygenic photosynthetic organisms are either formyl substitution (chlorophyll b, d, and f) or the degree of unsaturation (8-vinyl chlorophyll a and b) of a side chain of the macrocycle compared with chlorophyll a. We conducted an investigation of the conversion of vinyl to formyl groups among naturally occurring chlorophylls. We demonstrated the in vitro oxidative cleavage of vinyl side groups to yield formyl groups through the aid of a thiol-containing compound in aqueous reaction mixture at room temperature. Heme is required as a catalyst in aqueous solution but is not required in methanolic reaction mixture. The conversion of vinyl- to formyl- groups is independent of their position on the macrocycle, as we observed oxidative cleavages of both 3-vinyl and 8-vinyl side chains to yield formyl groups. Three new chlorophyll derivatives were synthesised using 8-vinyl chlorophyll a as substrate: 8-vinyl chlorophyll d, [8-formyl]-chlorophyll a, and [3,8-diformyl]-chlorophyll a. The structural and spectral properties will provide a signature that may aid in identification of the novel chlorophyll derivatives in natural systems. The ease of conversion of vinyl- to formyl- in chlorophylls demonstrated here has implications regarding the biosynthetic mechanism of chlorophyll d in vivo. PMID:25119484

  10. Magnitude Based Discrimination of Manmade Seismic Events From Naturally Occurring Earthquakes in Utah, USA

    NASA Astrophysics Data System (ADS)

    Koper, K. D.; Pechmann, J. C.; Burlacu, R.; Pankow, K. L.; Stein, J. R.; Hale, J. M.; Roberson, P.; McCarter, M. K.

    2016-12-01

    We investigate the feasibility of using the difference between local (ML) and coda duration (MC) magnitude as a means of discriminating manmade seismic events from naturally occurring tectonic earthquakes in and around Utah. Using a dataset of nearly 7,000 well-located earthquakes in the Utah region, we find that ML-MC is on average 0.44 magnitude units smaller for mining induced seismicity (MIS) than for tectonic seismicity (TS). MIS occurs within near-surface low-velocity layers that act as a waveguide and preferentially increase coda duration relative to peak amplitude, while the vast majority of TS occurs beneath the near-surface waveguide. A second dataset of more than 3,700 probable explosions in the Utah region also has significantly lower ML-MC values than TS, likely for the same reason as the MIS. These observations suggest that ML-MC, or related measures of peak amplitude versus signal duration, may be useful for discriminating small explosions from earthquakes at local-to-regional distances. ML and MC can be determined for small events with relatively few observations, hence an ML-MC discriminant can be effective in cases where moment tensor inversion is not possible because of low data quality or poorly known Green's functions. Furthermore, an ML-MC discriminant does not rely on the existence of the fast attenuating Rg phase at regional distances. ML-MC may provide a local-to-regional distance extension of the mb-MS discriminant that has traditionally been effective at identifying large nuclear explosions with teleseismic data. This topic is of growing interest in forensic seismology, in part because the Comprehensive Nuclear Test Ban Treaty (CTBT) is a zero tolerance treaty that prohibits all nuclear explosions, no matter how small. If the CTBT were to come into force, source discrimination at local distances would be required to verify compliance.

  11. Naturally occurring clay nanoparticles in Latosols of Brazil central region: detection and characterization

    NASA Astrophysics Data System (ADS)

    Dominika Dybowska, Agnieszka; Luciene Maltoni, Katia; Piella, Jordi; Najorka, Jens; Puntes, Victor; Valsami-Jones, Eugenia

    2015-04-01

    Stability and reactivity of minerals change as a particle size function, which makes mineral nanoparticles (defined here as <100 nm) fundamentally distinct from the larger size materials. Naturally occurring mineral nanoparticles contribute to many biogeochemical processes, however much remains to be learnt about these materials, their size dependent behavior and environmental significance. Advances in analytical, imaging and spectroscopic techniques made it now possible to study such particles; however we still have limited knowledge of their chemical, structural and morphological identity and reactivity, in particular in soils. The aim of this research was to characterize the naturally occurring nanoparticles in three soils from Brazil central region. The samples were collected in the A horizon, treated with H2O2 to remove organic material, dispersed in ultrasonic bath and wet sieved (53 µm) to remove the sand fraction. The clay fraction was collected by siphoning the supernatant, conditioned in 1000 ml cylinder, according to the Stock's law. This fraction was further processed by re-suspension in water, sonication and repeated centrifugation, to separate the fraction smaller than 100nm. This material, called here the soil "nanofraction", was analyzed using a range of techniques: 1) nanoparticle size/morphology and crystallinity with Transmission Electron Microscopy (TEM operateing in scanning (HAADF-STEM) and High Resolution (HRTEM) mode), 2) size distribution in water with Dynamic Light Scattering (DLS) and surface charge estimated from electrophoretic mobility measurements 3) crystal phase and crystallite size with X-ray Diffraction (XRD) 4) Chemical composition by quantitative analysis of elements (e.g., Si, Fe, Al, Ti) and their spatial distribution with HRTEM/EDS elemental mappings. The nanofraction had an average hydrodynamic particle diameter ranging from 83 to 92nm with a low polydispersity index of 0.13-0.17 and was found highly stable in aqueous

  12. Characterization of kidney damage using several renal biomarkers in dogs with naturally occurring heatstroke.

    PubMed

    Segev, G; Daminet, S; Meyer, E; De Loor, J; Cohen, A; Aroch, I; Bruchim, Y

    2015-11-01

    Heatstroke is often associated with acute kidney injury (AKI). The objectives of this study were to characterize the kidney damage occurring in canine heatstroke using routine and novel biomarkers and to assess their diagnostic and prognostic performance. Thirty dogs with naturally occurring heatstroke were enrolled prospectively. Blood and urine specimens were collected at presentation, at 4 h post-presentation and every 12 h until discharge or death. The glomerular filtration rate (GFR) and electrolyte fractional excretion (FE) at 4 h post-presentation were also calculated, based on urinary clearances. AKI was further characterized by evaluating urine neutrophil gelatinase-associated lipocalin/creatinine ratio (UNGAL), urine retinol-binding protein/creatinine ratio (URBP), urine C-reactive protein/creatinine ratio (UCRP) and urine protein to creatinine ratio (UPC). These biomarkers were compared to those for 13 healthy dogs. Thirteen dogs (43%) died and 17 (57%) survived. Median serum creatinine concentration at presentation was 1.69 mg/dL (range, 0.5-4.7 mg/dL), while concurrent GFR was markedly decreased (median 0.60 mL/min/kg; range, 0.00-3.10 mL/min/kg). Median Na fractional excretion was 0.08 (range, 0.01-0.41) and was an accurate predictor of AKI (area under curve 0.89; 95% confidence intervals 0.76-1.00). Median UPC at presentation was 4.8 (range, 0.4-46.0). Median UCRP, URBP and UNGAL were increased in all dogs with heatstroke, and were mean 232, 133, and 1213-fold higher than healthy control dogs, respectively. In conclusion, although AKI occurs invariably in dogs with heatstroke, it is often subclinical at presentation. Damage occurs in both the renal tubules and the glomeruli. Novel kidney function tests for the characterization of renal injury and its severity are superior to conventional markers and could be used to facilitate early diagnosis of AKI.

  13. Understanding the Radioactive Ingrowth and Decay of Naturally Occurring Radioactive Materials in the Environment: An Analysis of Produced Fluids from the Marcellus Shale.

    PubMed

    Nelson, Andrew W; Eitrheim, Eric S; Knight, Andrew W; May, Dustin; Mehrhoff, Marinea A; Shannon, Robert; Litman, Robert; Burnett, William C; Forbes, Tori Z; Schultz, Michael K

    2015-07-01

    The economic value of unconventional natural gas resources has stimulated rapid globalization of horizontal drilling and hydraulic fracturing. However, natural radioactivity found in the large volumes of "produced fluids" generated by these technologies is emerging as an international environmental health concern. Current assessments of the radioactivity concentration in liquid wastes focus on a single element-radium. However, the use of radium alone to predict radioactivity concentrations can greatly underestimate total levels. We investigated the contribution to radioactivity concentrations from naturally occurring radioactive materials (NORM), including uranium, thorium, actinium, radium, lead, bismuth, and polonium isotopes, to the total radioactivity of hydraulic fracturing wastes. For this study we used established methods and developed new methods designed to quantitate NORM of public health concern that may be enriched in complex brines from hydraulic fracturing wastes. Specifically, we examined the use of high-purity germanium gamma spectrometry and isotope dilution alpha spectrometry to quantitate NORM. We observed that radium decay products were initially absent from produced fluids due to differences in solubility. However, in systems closed to the release of gaseous radon, our model predicted that decay products will begin to ingrow immediately and (under these closed-system conditions) can contribute to an increase in the total radioactivity for more than 100 years. Accurate predictions of radioactivity concentrations are critical for estimating doses to potentially exposed individuals and the surrounding environment. These predictions must include an understanding of the geochemistry, decay properties, and ingrowth kinetics of radium and its decay product radionuclides.

  14. Mobilization of arsenic and other naturally occurring contaminants in groundwater of the Main Ethiopian Rift aquifers.

    PubMed

    Rango, Tewodros; Vengosh, Avner; Dwyer, Gary; Bianchini, Gianluca

    2013-10-01

    This study investigates the mechanisms of arsenic (As) and other naturally occurring contaminants (F(-), U, V, B, and Mo) mobilization from Quaternary sedimentary aquifers of the Main Ethiopian Rift (MER) and their enrichment in the local groundwater. The study is based on systematic measurements of major and trace elements as well as stable oxygen and hydrogen isotopes in groundwater, coupled with geochemical and mineralogical analyses of the aquifer rocks. The Rift Valley aquifer is composed of rhyolitic volcanics and Quaternary lacustrine sediments. X-ray fluorescence (XRF) results revealed that MER rhyolites (ash, tuff, pumice and ignimbrite) and sediments contain on average 72 wt. % and 65 wt. % SiO2, respectively. Petrographic studies of the rhyolites indicate predominance of volcanic glass, sanidine, pyroxene, Fe-oxides and plagioclase. The As content in the lacustrine sediments (mean = 6.6 mg/kg) was higher than that of the rhyolites (mean: 2.5 mg/kg). The lacustrine aquifers of the Ziway-Shala basin in the northern part of MER were identified as high As risk zones, where mean As concentration in groundwater was 22.4 ± 33.5 (range of 0.60-190 μg/L) and 54% of samples had As above the WHO drinking water guideline value of 10 μg/L. Field As speciation measurements showed that most of the groundwater samples contain predominantly (~80%) arsenate-As(V) over arsenite-As(III) species. The As speciation together with field data of redox potential (mean Eh = +73 ± 65 mV) and dissolved-O2 (6.6 ± 2.2 mg/L) suggest that the aquifer is predominantly oxidative. Water-rock interactions, including the dissolution of volcanic glass produces groundwater with near-neutral to alkaline pH (range 6.9-8.9), predominance of Na-HCO3 ions, and high concentration of SiO2 (mean: 85.8 ± 11.3 mg/L). The groundwater data show high positive correlation of As with Na, HCO3, U, B, V, and Mo (R(2) > 0.5; p < 0.001). Chemical modeling of the groundwater indicates that Fe-oxides and

  15. Radiometric method for determining concentration of naturally occurring isotopes and device therefor

    SciTech Connect

    Yakubovich, S.L.; Gerling, V.E.; Golubnichy, V.V.; Kotsen, M.E.; Stepanov, J.N.

    1984-10-09

    The proposed method essentially consists in that a sample of a substance is placed between two scintillators in immediate contact therewith whereupon said sample is hermetically sealed. Arranged in close proximity to each scintillator is a photomultiplier tube recording ionizing ..cap alpha..- and b-radiation. A selector is utilized to select pulses corresponding to ..cap alpha..- and b-particles, and delayed coincidence circuits of a recording element separate and record b-..cap alpha.. and ..cap alpha..-..cap alpha.. cascade pairs of delayed coincidences of RaC, ThC, and AcA radionuclides. Flows are measured twice at a predetermined time interval to account for emanation build-up tendency and concentration of isotopes of radium is determined from a formula.

  16. Effects of naturally occurring coumarins on hepatic drug-metabolizing enzymes inmice

    SciTech Connect

    Kleiner, Heather E. Xia, Xiaojun; Sonoda, Junichiro; Zhang, Jun; Pontius, Elizabeth; Abey, Jane; Evans, Ronald M.; Moore, David D.; DiGiovanni, John

    2008-10-15

    Cytochromes P450 (P450s) and glutathione S-transferases (GSTs) constitute two important enzyme families involved in carcinogen metabolism. Generally, P450s play activation or detoxifying roles while GSTs act primarily as detoxifying enzymes. We previously demonstrated that oral administration of the linear furanocoumarins, isopimpinellin and imperatorin, modulated P450 and GST activities in various tissues of mice. The purpose of the present study was to compare a broader range of naturally occurring coumarins (simple coumarins, and furanocoumarins of the linear and angular type) for their abilities to modulate hepatic drug-metabolizing enzymes when administered orally to mice. We now report that all of the different coumarins tested (coumarin, limettin, auraptene, angelicin, bergamottin, imperatorin and isopimpinellin) induced hepatic GST activities, whereas the linear furanocoumarins possessed the greatest abilities to induce hepatic P450 activities, in particular P450 2B and 3A. In both cases, this corresponded to an increase in protein expression of the enzymes. Induction of P4502B10, 3A11, and 2C9 by xenobiotics often is a result of activation of the pregnane X receptor (PXR) and/or constitutive androstane receptor (CAR). Using a pregnane X receptor reporter system, our results demonstrated that isopimpinellin activated both PXR and its human ortholog SXR by recruiting coactivator SRC-1 in transfected cells. In CAR transfection assays, isopimpinellin counteracted the inhibitory effect of androstanol on full-length mCAR, a Gal4-mCAR ligand-binding domain fusion, and restored coactivator binding. Orally administered isopimpinellin induced hepatic mRNA expression of Cyp2b10, Cyp3a11, and GSTa in CAR(+/+) wild-type mice. In contrast, the induction of Cyp2b10 mRNA by isopimpinellin was attenuated in the CAR(-/-) mice, suggesting that isopimpinellin induces Cyp2b10 via the CAR receptor. Overall, the current data indicate that naturally occurring coumarins have

  17. Molecular characterization of a naturally occurring intraspecific recombinant begomovirus with close relatives widespread in southern Arabia

    PubMed Central

    2014-01-01

    Background Tomato leaf curl Sudan virus (ToLCSDV) is a single-stranded DNA begomovirus of tomato that causes downward leaf curl, yellowing, and stunting. Leaf curl disease results in significant yield reduction in tomato crops in the Nile Basin. ToLCSDV symptoms resemble those caused by Tomato yellow leaf curl virus, a distinct and widespread begomovirus originating in the Middle East. In this study, tomato samples exhibiting leaf curl symptoms were collected from Gezira, Sudan. The associated viral genome was molecularly characterized, analyzed phylogenetically, and an infectious clone for one isolate was constructed. Findings The complete genomes for five newly discovered variants of ToLCSDV, ranging in size from 2765 to 2767-bp, were cloned and sequenced, and subjected to pairwise and phylogenetic analyses. Pairwise analysis indicated that the five Gezira isolates shared 97-100% nucleotide identity with each other. Further, these variants of ToLCSDV shared their highest nucleotide identity at 96-98%, 91-95%, 91-92%, and 91-92% with the Shambat, Gezira, Oman and Yemen strains of ToLCSDV, respectively. Based on the high maximum nucleotide identities shared between these ToLCSDV variants from Gezira and other previously recognized members of this taxonomic group, they are considered isolates of the Shambat strain of ToLCSDV. Analysis of the complete genome sequence for these new variants revealed that they were naturally occurring recombinants between two previously reported strains of ToLCSDV. Finally, a dimeric clone constructed from one representative ToLCSV genome from Gezira was shown to be infectious following inoculation to tomato and N. benthamiana plants. Conclusion Five new, naturally occurring recombinant begomovirus variants (>96% shared nt identity) were identified in tomato plants from Gezira in Sudan, and shown to be isolates of the Shambat strain of ToLCSDV. The cloned viral genome was infectious in N. benthamiana and tomato plants, and symptoms in

  18. Effect of calcitonin pretreatment on naturally occurring intervertebral disc degeneration in guinea pig

    PubMed Central

    Jiang, Xiaohua; Tian, Faming; Wang, Wenya; Yan, Jinyin; Liu, Huanjiang; Liu, Binbin; Song, Huiping; Zhang, Yingze; Shen, Yong; Zhang, Liu

    2015-01-01

    Introduction: Our previous study suggested protective effects of calcitonin (CT) on experimental osteoarthritis. The aim of the present study was to provide evidence of whether CT pretreatment could prevent naturally occurring intervertebral disc degeneration in guinea pigs. Methods: Forty-two 3 months old female guinea pigs were randomly assigned into 2 groups as follows: Twenty-four were treated by normal saline as control group and sacrificed at 3, 6, 9 and 12 months of age (6 animals at each time point), the other 18 were received salmon CT (8 ug/kg/day, everyday) treatment at 3 months of age and sacrificed at the age of 6, 9 and 12 months respectively. Van Gieson stain and the histological score were used to identify the histological changes of the lumbar intervertebral discs. The disc height and vertebral body height were measured. Immunohistochemistry measurements for glycosaminoglycan, type II collagen, and matrix metalloprotease (MMP)-1 expressions were performed. Bone quality and microstructural changes in the L3-6 lumbar vertebral bodies were assessed by bone mineral density (BMD), micro-CT analysis and biomechanical testing. Results: Histological analysis indicated significantly higher disc degeneration scores in 9-month-old guinea pigs in comparison with younger animals, and grew higher with increasing age. CT treatment significantly reduced the histological score, and increased the disc height and the ratio to vertebral body height in 12 months old animals, as well as upregulated the glycosaminoglycan, type II collagen and inhibited the MMP-1 expression. Micro-CT analysis showed decreased percent bone volume (BV/TV) and increased trabecular separation (Tb.Sp), structural model index (SMI) in 12 months old animals in comparison with the younger animals. Markedly increased BV/TV and decreased Tb.Sp were observed in CT treated animals when compared with control animals. The biomechanical properties including maximum load, maximum stress, yield stress and

  19. Naturally Occurring Structural Isomers in Serum IgA1 O-Glycosylation

    PubMed Central

    Takahashi, Kazuo; Smith, Archer D.; Poulsen, Knud; Kilian, Mogens; Julian, Bruce A.; Mestecky, Jiri; Novak, Jan; Renfrow, Matthew B.

    2013-01-01

    IgA is the most abundantly produced antibody and plays an important role in the mucosal immune system. Human IgA is represented by two isotypes, IgA1 and IgA2. The major structural difference between these two subclasses is the presence of nine potential sites of O-glycosylation in the hinge region between the first and second constant region domains of the heavy chain. Thr225, Thr228, Ser230, Ser232 and Thr236 have been identified as the predominant sites of O-glycan attachment. The range and distribution of O-glycan chains at each site within the context of adjacent sites in this clustered region create a complex heterogeneity of surface epitopes that is incompletely defined. We previously described the analysis of IgA1 O-glycan heterogeneity by use of high resolution LC/MS and electron capture dissociation tandem MS to unambiguously localize all amino acid attachment sites in IgA1 (Ale) myeloma protein. Here, we report the identification and elucidation of IgA1 O-glycopeptide structural isomers that occur based on amino acid position of the attached glycans (positional isomers) and the structure of the O-glycan chains at individual sites (glycan isomers). These isomers are present in a model IgA1 (Mce1) myeloma protein and occur naturally in normal human serum IgA1. Variable O-glycan chains attached to Ser230, Thr233 or Thr236 produce the predominant positional isomers, including O-glycans composed of a single GalNAc residue. These findings represent the first definitive identification of structural isomeric IgA1 O-glycoforms, define the single-site heterogeneity for all O-glycan sites in a single sample, and have implications for defining epitopes based on clustered O-glycan variability. PMID:22067045

  20. Naturally occurring structural isomers in serum IgA1 o-glycosylation.

    PubMed

    Takahashi, Kazuo; Smith, Archer D; Poulsen, Knud; Kilian, Mogens; Julian, Bruce A; Mestecky, Jiri; Novak, Jan; Renfrow, Matthew B

    2012-02-03

    IgA is the most abundantly produced antibody and plays an important role in the mucosal immune system. Human IgA is represented by two isotypes, IgA1 and IgA2. The major structural difference between these two subclasses is the presence of nine potential sites of O-glycosylation in the hinge region between the first and second constant region domains of the heavy chain. Thr(225), Thr(228), Ser(230), Ser(232) and Thr(236) have been identified as the predominant sites of O-glycan attachment. The range and distribution of O-glycan chains at each site within the context of adjacent sites in this clustered region create a complex heterogeneity of surface epitopes that is incompletely defined. We previously described the analysis of IgA1 O-glycan heterogeneity by use of high resolution LC-MS and electron capture dissociation tandem MS to unambiguously localize all amino acid attachment sites in IgA1 (Ale) myeloma protein. Here, we report the identification and elucidation of IgA1 O-glycopeptide structural isomers that occur based on amino acid position of the attached glycans (positional isomers) and the structure of the O-glycan chains at individual sites (glycan isomers). These isomers are present in a model IgA1 (Mce1) myeloma protein and occur naturally in normal human serum IgA1. Variable O-glycan chains attached to Ser(230), Thr(233) or Thr(236) produce the predominant positional isomers, including O-glycans composed of a single GalNAc residue. These findings represent the first definitive identification of structural isomeric IgA1 O-glycoforms, define the single-site heterogeneity for all O-glycan sites in a single sample, and have implications for defining epitopes based on clustered O-glycan variability.

  1. Early and delayed effects of naturally occurring asbestos on serum biomarkers of inflammation and metabolism.

    PubMed

    Kodavanti, Urmila P; Andrews, Debora; Schladweiler, Mette C; Gavett, Stephen H; Dodd, Darol E; Cyphert, Jaime M

    2014-01-01

    Studies recently showed that intratracheal (IT) instillation of Libby amphibole (LA) increases circulating acute-phase proteins (APP; α-2 macroglobulin, A2M; and α-1 acid glycoprotein, AGP) and inflammatory biomarkers (osteopontin and lipocalin) in rats. In this study, objectives were to (1) compare changes in biomarkers of rats after instillation of different naturally occurring asbestos (NOA) minerals including LA, Sumas Mountain chrysotile (SM), El Dorado Hills tremolite (ED), and Ontario ferroactinolite cleavage fragments (ON), and (2) examine biomarkers after subchronic LA or amosite inhalation exposure. Rat-respirable fractions (aerodynamic diameter approximately 2.5 μm) prepared by water elutriation were delivered via a single IT instillation at doses of 0, 0.5, and 1.5 mg/rat in male F344 rats. Nose-only inhalation exposures were performed at 0, 1, 3.3, and 10 mg/m(3) for LA and at 3.3 mg /m(3) for amosite, 6h/d, 5 d/wk for 13 wk. Inflammation, metabolic syndrome, and cancer biomarkers were analyzed in the serum for up to 18 mo. IT instillation of some asbestos materials significantly increased serum AGP and A2M but to a varying degree (SM = LA > ON = ED). Numerical increases in interleukin (IL)-6 and osteopontin occurred in rats instilled with SM. SM and ED also elevated leptin and insulin at 15 mo, suggesting potential metabolic effects. LA inhalation tended to raise A2M at d 1 but not cytokines. Serum mesothelin appeared to elevate after 18 mo of LA inhalation. These results suggest that the lung injury induced by high levels of asbestos materials may be associated with systemic inflammatory changes and predisposition to insulin resistance.

  2. Further evidence for GHB naturally occurring in common non-alcoholic beverages.

    PubMed

    Elliott, Simon P; Fais, Paolo

    2017-08-01

    GHB has been implicated in many cases of suspected surreptitious administration with the purpose of increasing victim vulnerability to sexual assault. Low amounts of endogenous (or naturally occurring) GHB, which do not reach pharmacologically active levels, have been detected in alcoholic and non-alcoholic beverages. Due to the continued requirement to obtain data on the presence of endogenous GHB in various beverage types, GHB concentrations were measured in a series of non-alcoholic beverages. Tonic water and lemon flavoured tonic water beverages were analysed at 0, 24 and 96h after the bottle opening using gas chromatography coupled to tandem mass spectrometry (GC-MS/MS) on an Agilent 6890/7000C Triple Quadrupole. GHB was detected in all beverages at very low amounts ranging from 89 to 145ng/mL (0.089-0.145mg/L) and did not demonstrate a general trend of variation for concentration along the tested time span (96h). The presented data provide additional evidence for the endogenous nature of GHB in non-alcoholic beverages at very low concentrations, which are many orders of magnitude lower than those described to produce any pharmacological effect on the subject. However, when considering a case of alleged drug-facilitated sexual assault, a low level of GHB detected in a drink may be related both to a surreptitiously GHB administration with subsequent dilution for concealment or to the presence of endogenous GHB. On this basis, a comprehensive analysis of all the available information, including circumstantial data demonstrating possible attempts to conceal GHB administration and an assessment of levels of endogenous GHB in the suspected beverage type, is of the utmost importance for a proper interpretation of the toxicological results. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Corticosterone regulates both naturally occurring and cocaine-induced dopamine signaling by selectively decreasing dopamine uptake.

    PubMed

    Wheeler, Daniel S; Ebben, Amanda L; Kurtoglu, Beliz; Lovell, Marissa E; Bohn, Austin T; Jasek, Isabella A; Baker, David A; Mantsch, John R; Gasser, Paul J; Wheeler, Robert A

    2017-10-01

    Stressful and aversive events promote maladaptive reward-seeking behaviors such as drug addiction by acting, in part, on the mesolimbic dopamine system. Using animal models, data from our lab and others show that stress and cocaine can interact to produce a synergistic effect on reward circuitry. This effect is also observed when the stress hormone corticosterone is administered directly into the nucleus accumbens (NAc), indicating that glucocorticoids act locally in dopamine terminal regions to enhance cocaine's effects on dopamine signaling. However, prior studies in behaving animals have not provided mechanistic insight. Using fast-scan cyclic voltammetry, we examined the effect of systemic corticosterone on spontaneous dopamine release events (transients) in the NAc core and shell in behaving rats. A physiologically relevant systemic injection of corticosterone (2 mg/kg i.p.) induced an increase in dopamine transient amplitude and duration (both voltammetric measures sensitive to decreases in dopamine clearance), but had no effect on the frequency of transient release events. This effect was compounded by cocaine (2.5 mg/kg i.p.). However, a second experiment indicated that the same injection of corticosterone had no detectable effect on the dopaminergic encoding of a palatable natural reward (saccharin). Taken together, these results suggest that corticosterone interferes with naturally-occurring dopamine uptake locally, and this effect is a critical determinant of dopamine concentration specifically in situations in which the dopamine transporter is pharmacologically blocked by cocaine. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  4. Infrared spectroscopic examination of the interaction of urea with the naturally occurring zeolite clinoptilolite

    USGS Publications Warehouse

    Byler, D.M.; Gerasimowicz, W.V.; Stockette, V.M.; Eberl, D.D.

    1991-01-01

    Infrared spectroscopy has shown for the first time that the naturally occurring zeolite clinoptilolite can absorb urea, (NH2)2CO, under ambient conditions from either aqueous or ethanolic solutions. The two strongest NH stretching bands at 3441 and 3344 cm-1 in pure, solid urea shift to higher frequency (about 3504 and 3401 cm-1) after absorption. Two of the four urea bands in the 1800-1300 cm-1 range (at 1683 and 1467 cm-1) undergo marked downward shifts to about 1670 and 1445 cm-1. The other two bands show little change in frequency. The strong band at 1602 cm-1, however, diminishes in intensity to little more than an ill-defined shoulder on the 1626-cm-1 peak. When clinoptilolite is heated to 450 ??C and then treated with molten urea (ca. 140 ??C) for several minutes, and finally washed twice with ethanol to remove excess unreacted urea, further changes become apparent in the spectrum of the urea-treated clinoptilolite. The two NH stretching bands broaden without significant change in frequency. Two new bands appear in the midfrequency range at 1777 (weak) and 1719 (medium strong) cm-1. Of the four original midfrequency peaks, the one at 1602 cm-1 is now absent. Two others (1627 and 1440 cm-1) exhibit little change, while the fourth has broadened and shifted down to 1663 cm-1, where it appears as a shoulder on the band at 1627 cm-1. Both treatments clearly induce interaction between urea and the zeolite which seems to result in significant modifications in the nature of the hydrogen bonding of the substrate. ?? 1991.

  5. Naturally Occurring Monoclonal Antibodies and Their Therapeutic Potential for Neurologic Diseases.

    PubMed

    Wootla, Bharath; Watzlawik, Jens O; Warrington, Arthur E; Wittenberg, Nathan J; Denic, Aleksandar; Xu, Xiaohua; Jordan, Luke R; Papke, Louisa M; Zoecklein, Laurie J; Pierce, Mabel L; Oh, Sang-Hyun; Kantarci, Orhun H; Rodriguez, Moses

    2015-11-01

    Modulating the immune system does not reverse long-term disability in neurologic disorders. Better neuroregenerative and neuroprotective treatment strategies are needed for neuroinflammatory and neurodegenerative diseases. To review the role of monoclonal, naturally occurring antibodies (NAbs) as novel therapeutic molecules for treatment of neurologic disorders. Peer-reviewed articles, including case reports, case series, retrospective reviews, prospective randomized clinical trials, and basic science reports, were identified in a PubMed search for articles about NAbs and neurologic disorders that were published from January 1, 1964, through June 30, 2015. We concentrated our review on multiple sclerosis, Parkinson disease, Alzheimer disease, and amyotrophic lateral sclerosis. Many insults, including trauma, ischemia, infection, inflammation, and neurodegeneration, result in irreversible damage to the central nervous system. Central nervous system injury often results in a pervasive inhibitory microenvironment that hinders regeneration. A common targeted drug development strategy is to identify molecules with high potency in animal models. Many approaches often fail in the clinical setting owing to a lack of efficacy in human diseases (eg, less than the response demonstrated in animal models) or a high incidence of toxic effects. An alternative approach is to identify NAbs in humans because these therapeutic molecules have potential physiologic function without toxic effects. NAbs of the IgG, IgA, or IgM isotype contain germline or close to germline sequences and are reactive to self-components, altered self-components, or foreign antigens. Our investigative group developed recombinant, autoreactive, natural human IgM antibodies directed against oligodendrocytes or neurons with therapeutic potential for central nervous system repair. One such molecule, recombinant HIgM22, directed against myelin and oligodendrocytes completed a successful phase 1 clinical trial

  6. Spectral Analysis of Naturally Occurring Methylxanthines (Theophylline, Theobromine and Caffeine) Binding with DNA

    PubMed Central

    Johnson, Irudayam Maria; Prakash, Halan; Prathiba, Jeyaguru; Raghunathan, Raghavachary; Malathi, Raghunathan

    2012-01-01

    Nucleic acids exist in a dynamic equilibrium with a number of molecules that constantly interact with them and regulate the cellular activities. The inherent nature of the structure and conformational integrity of these macromolecules can lead to altered biological activity through proper targeting of nucleic acids binding ligands or drug molecules. We studied the interaction of naturally occurring methylxanthines such as theophylline, theobromine and caffeine with DNA, using UV absorption and Fourier transform infrared (FTIR) spectroscopic methods, and especially monitored their binding affinity in the presence of Mg2+ and during helix-coil transitions of DNA by temperature (Tm) or pH melting profiles. The study indicates that all these molecules effectively bind to DNA in a dose dependent manner. The overall binding constants of DNA-theophylline = 3.5×103 M−1, DNA-theobromine = 1.1×103 M−1, and DNA-Caffeine = 3.8×103 M−1. On the other hand Tm/pH melting profiles showed 24–35% of enhanced binding activity of methylxanthines during helix-coil transitions of DNA rather than to its native double helical structure. The FTIR analysis divulged that theophylline, theobromine and caffeine interact with all the base pairs of DNA (A-T; G-C) and phosphate group through hydrogen bond (H-bond) interaction. In the presence of Mg2+, methylxanthines altered the structure of DNA from B to A-family. However, the B-family structure of DNA remained unaltered in DNA-methylxanthines complexes or in the absence of Mg2+. The spectral analyses indicated the order of binding affinity as “caffeine≥theophylline>theobromine” to the native double helical DNA, and “theophylline≥theobromine>caffeine to the denatured form of DNA and in the presence of divalent metal ions. PMID:23236361

  7. Cytotoxicity of seven naturally occurring phenolic compounds towards multi-factorial drug-resistant cancer cells.

    PubMed

    Kuete, Victor; Mbaveng, Armelle T; Nono, Eric C N; Simo, Christophe C; Zeino, Maen; Nkengfack, Augustin E; Efferth, Thomas

    2016-07-15

    In medical oncology, multi-drug resistance (MDR) of cancer cells continues to be a major impediment. We are in quest of novel anti-proliferative agents to overcome drug-resistant tumor cells. In the present study, we investigated the cytotoxicity of 7 naturally occurring phenolic compounds including two isoflavonoids alpinumisoflavone (1) and laburnetin (2), one biflavonoid amentoflavone (3), three lignans pycnanthulignene A (4), pycnanthulignene B (5), and syringaresinol (7) and one xanthone, euxanthone (6) against 9 drug-sensitive and MDR cancer cell lines. The resazurin reduction assay was used to evaluate the cytotoxicity of these compounds, whilst caspase-Glo assay was used to detect caspase activation. Cell cycle, mitochondrial membrane potential (MMP) and levels of reactive oxygen species (ROS) were all analyzed via flow cytometry. The IC50 values for the investigational phenolics ranged from 5.91 µM (towards leukemia CEM/ADR5000 cells) to 65.65 µM (towards drug-resistant breast adenocarcinoma MDA-MB-231-BCRP cells) for 1, 27.63 µM (towards leukemia CCRF-CEM cells) to 107.57 µM (towards MDA-MB-231-pcDNA cells) for 2, from 5.84 µM (towards CEM/ADR5000 cells) to 65.32 µM (towards colon carcinoma HCT116 (p53(-/-)) cells) for 4 and 0.20 µM (towards CCRF-CEM cells) to 195.12 µM (towards leukemia CEM/ADR5000) for doxorubicin. Phenolics 3, 5, 6 and 7 displayed selectivity cytotoxic effects on cancer cells lines. Compounds 1 and 4 induced apoptosis in CCRF-CEM cells, mediated by loss of MMP and increase ROS production. The studied phenolics and mostly isoflavonoid 1 and lignan 4 are potential cytotoxic natural products that deserve more investigations to develop novel antineoplastic drugs against multifactorial drug-resistant cancers. Copyright © 2016 Elsevier GmbH. All rights reserved.

  8. Persistence of naturally occurring antibiotic resistance genes in the bacteria and bacteriophage fractions of wastewater.

    PubMed

    Calero-Cáceres, William; Muniesa, Maite

    2016-05-15

    The emergence and prevalence of antibiotic resistance genes (ARGs) in the environment is a serious global health concern. ARGs from bacteria can be mobilized by mobile genetic elements, and recent studies indicate that phages and phage-derived particles, among others, could play a role in the spread of ARGs through the environment. ARGs are abundant in the bacterial and bacteriophage fractions of water bodies and for successful transfer of the ARGs, their persistence in these environments is crucial. In this study, three ARGs (blaTEM, blaCTX-M and sul1) that naturally occur in the bacterial and phage fractions of raw wastewater were used to evaluate the persistence of ARGs at different temperatures (4 °C, 22 °C and 37 °C) and pH values (3, 7 and 9), as well as after various disinfection treatments (thermal treatment, chlorination and UV) and natural inactivation in a mesocosm. Gene copies (GC) were quantified by qPCR; then the logarithmic reduction and significance of the differences between their numbers were evaluated. The ARGs persisted for a long time with minimal reductions after all the treatments. In general, they showed greater persistence in the bacteriophage fraction than in the bacterial fraction. Comparisons showed that the ARGs persisted under conditions that reduced culturable Escherichia coli and infectious coliphages below the limit of detection. The prevalence of ARGs, particularly in the bacteriophage fraction, poses the threat of the spread of ARGs and their incorporation into a new bacterial background that could lead to the emergence of new resistant clones. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Pulmonary ultrasonographic abnormalities associated with naturally occurring equine influenza virus infection in standardbred racehorses.

    PubMed

    Gross, Diane K; Morley, Paul S; Hinchcliff, Kenneth W; Reichle, Jean K; Slemons, Richard D

    2004-01-01

    The purpose of this investigation was to determine if naturally occurring acute infectious upper respiratory disease (IRD) caused by equine influenza virus is associated with ultrasonographically detectable pleural and pulmonary abnormalities in horses. Standardbred racehorses were evaluated for signs of IRD, defined as acute coughing or mucopurulent nasal discharge. For every horse with IRD (n = 16), 1 or 2 horses with no signs of IRD and the same owner or trainer (n = 30) were included. Thoracic ultrasonography was performed within 5-10 days of the onset of clinical disease in horses with IRD. Horses without IRD were examined at the same time as the horses with IRD with which they were enrolled. The rank of the ultrasound scores of horses with IRD was compared to that of horses without IRD. Equine influenza virus was identified as the primary etiologic agent associated with IRD in this study. Mild lung consolidation and peripheral pulmonary irregularities were found in 11 (69%) of 16 of the horses with IRD and 11 (37%) of 30 of control horses. Lung consolidation (median score = 1) and peripheral irregularities scores (median score = 1) were greater in horses with IRD compared to horses without IRD (median score = 0; P < .05). Pleural effusion was not observed. Equine influenza virus infection can result in abnormalities of the equine lower respiratory tract. Despite the mild nature of IRD observed in this study, lung consolidation and peripheral pulmonary irregularities were more commonly observed in horses with clinical signs of IRD. Further work is needed to determine the clinical significance of these ultrasonographic abnormalities.

  10. Long-term toxicity of naturally occurring asbestos in male Fischer 344 rats.

    PubMed

    Cyphert, Jaime M; McGee, Marie A; Nyska, Abraham; Schladweiler, Mette C; Kodavanti, Urmila P; Gavett, Stephen H

    2016-01-01

    Naturally occurring asbestos (NOA) fibers are found in geologic deposits that may be disturbed by mining, earthworks, or natural processes, resulting in adverse health risks to exposed individuals. The toxicities of Libby amphibole and NOA samples including Sumas Mountain chrysotile (SM), El Dorado tremolite (ED), and Ontario ferroactinolite cleavage fragments (ON) were compared in male Fischer 344 (F344) rats 15 mo after exposure. Rat-respirable fractions of LA and SM displayed greater mean lengths and aspect ratios than ED and ON. After a single intratracheal (IT) instillation (0.5 or 1.5 mg/rat), persistent changes in ventilatory parameters and a significant increase in lung resistance at baseline and after methacholine aerosol dosing were found only in rats exposed to 1.5 mg SM. High-dose ED significantly elevated bronchoalveolar lavage lactate dehydrogenase (LDH) activity and protein levels, while high-dose SM increased γ-glutamyl transferase and LDH activities. A moderate degree of lung interstitial fibrosis after exposure to 1.5 mg SM persisted 15 mo after exposure, unchanged from previous findings at 3 mo. LA induced mild fibrosis, while ED and ON produced minimal and no apparent fibrosis, respectively. Bronchioloalveolar carcinoma was observed 15 mo after exposure to LA or ED. Data demonstrated that SM, given by bolus IT dosing on an equivalent mass basis, induced greater pulmonary function deficits, airway hyperresponsiveness, and interstitial fibrosis than other NOA, although unlike LA and ED, no apparent evidence for carcinogenicity was found. All NOA samples except ON cleavage fragments produced some degree of long-term toxicity.

  11. Measurements of natural radionuclides in human teeth and animal bones as markers of radiation exposure from soil in the Northern Malaysian Peninsula

    NASA Astrophysics Data System (ADS)

    Almayahi, B. A.; Tajuddin, A. A.; Jaafar, M. S.

    2014-04-01

    This study aimed to estimate the radioactive accumulation of the radionuclides 40K, 137Cs, 210Pb, 226Ra, 228Ra, and 228Th in extracted human teeth, animal bones, and soil. The natural radionuclides were measured by high-purity germanium spectroscopy in extracted human teeth and animal bones from people and animals living in different states in the Northern Malaysian Peninsula. The average 40K, 137Cs, 210Pb, 226Ra, 228Ra, and 228Th concentrations in teeth were found to be 12.31±7.27 Bq g-1, 0.48±0.21 Bq g-1, 0.56±0.21 Bq g-1, 0.55±0.23 Bq g-1, 1.82±1.28 Bq g-1, and 0.50±0.14 Bq g-1, respectively. The corresponding concentrations in bones were found to be 3.79±0.81 Bq g-1, 0.07±0.02 Bq g-1, 0.08±0.02 Bq g-1, 0.16±0.04 Bq g-1, 0.51±1.08 Bq g-1, and 0.06±0.02 Bq g-1, respectively. The corresponding radionuclide concentrations in teeth from smokers were higher than those in non-smokers, and the corresponding radionuclide concentrations were higher in female teeth than in male teeth. The corresponding radionuclide concentrations were higher in teeth than in bones. A positive correlation was found between radionuclides in both teeth and bone samples.

  12. Developments in Bioremediation of Soils and Sediments Pollutedwith Metals and Radionuclides: 2. Field Research on Bioremediation of Metals and Radionuclides

    SciTech Connect

    Hazen, Terry C.; Tabak, Henry H.

    2007-03-15

    Bioremediation of metals and radionuclides has had manyfield tests, demonstrations, and full-scale implementations in recentyears. Field research in this area has occurred for many different metalsand radionuclides using a wide array of strategies. These strategies canbe generally characterized in six major categories: biotransformation,bioaccumulation/bisorption, biodegradation of chelators, volatilization,treatment trains, and natural attenuation. For all field applicationsthere are a number of critical biogeochemical issues that most beaddressed for the successful field application. Monitoring andcharacterization parameters that are enabling to bioremediation of metalsand radionuclides are presented here. For each of the strategies a casestudy is presented to demonstrate a field application that uses thisstrategy.

  13. Pennsylvania's technologically enhanced, naturally occurring radioactive material experiences and studies of the oil and gas industry.

    PubMed

    Allard, David J

    2015-02-01

    This presentation provides an overview of the Commonwealth of Pennsylvania's experiences and ongoing studies related to technologically enhanced, naturally occurring radioactive material (TENORM) in the oil and gas industry. It has been known for many years that Pennsylvania's geology is unique, with several areas having relatively high levels of natural uranium and thorium. In the 1950s, a few areas of the state were evaluated for commercial uranium production. In the late 1970s, scoping studies of radon in homes prompted the Pennsylvania Department of Environmental Protection (DEP) Bureau of Radiation Protection (BRP) to begin planning for a larger state-wide radon study. The BRP and Oil and Gas Bureau also performed a TENORM study of produced water in the early 1990s for a number of conventional oil and gas wells. More recently, BRP and the Bureau of Solid Waste developed radiation monitoring regulations for all Pennsylvania solid waste disposal facilities. These were implemented in 2001, prompting another evaluation of oil and gas operations and sludge generated from the treatment of conventionally produced water and brine but mainly focused on the disposal of TENORM solid waste in the state's Resource Conservation and Recovery Act Subtitle D landfills. However, since 2008, the increase in volumes of gas well wastewater and levels of Ra observed in the unconventional shale gas well flow-back fracking water has compelled DEP to fully re-examine these oil and gas operations. Specifically, with BRP in the lead, a new TENORM study of oil and gas operations and related wastewater treatment operations has been initiated (), supported by an American National Standards Institute standard on TENORM () and a U.S. Government Accountability Office report on shale resource development and risks (). This study began in early 2013 and will examine the potential public and worker radiation exposure and environmental impact as well as re-evaluate TENORM waste disposal. This

  14. Colloid-Facilitated Transport of Contaminants in Groundwater: Mobilization of Transuranic Radionuclides from Disposal Trenches by Natural Organic Matter

    NASA Astrophysics Data System (ADS)

    McCarthy, J. F.

    1998-03-01

    The role of natural organic matter (NOM) in enhancing the field-scale transport of transuranic radionuclides (TRU) in groundwater is used as a case study to illustrate the value of integrated laboratory and field approaches to understanding colloid-facilitated transport. Field observations provide evidence that TRU are mobilized and co-transported by NOM when hydrologic processes bring the groundwater in contact with waste buried in shallow trenches. This hypothesis receives further support from laboratory speciation studies and geochemical modeling. However, laboratory sorption studies indicate that the groundwater NOM should sorb to, and thus be retarded by the mineral surfaces of the formation. This issue is resolved through field studies of NOM transport. Discrepancies between laboratory predictions and field results reveal that the key process in NOM transport in natural-as opposed to model laboratory-systems is competitive adsorption among NOM subcomponents. Unlike laboratory studies of adsorption of NOM to clean mineral surfaces, surfaces in natural systems are coated with groundwater NOM, and binding sites are “passivated” with respect to further binding of the