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| Registros recuperados: 601 | |
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| Michael G. Ikonomou; Sierra Rayne; Norman F. Crewe. |
| Concentrations of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), and polybrominated diphenyl ethers (PBDEs) were examined as a function of depth in killer whale (Orcinus orca) blubber samples. Lipid-normalized concentrations of PCBs, PCDD/Fs, and PBDEs did not display significant variation with depth in three distinct blubber layers (outer, central, and inner). Significantly more variation in contaminant concentrations were observed with depth on a wet weight basis for the killer whale sample. The current study indicates that non-invasive microdart biopsy sampling methods commonly used for monitoring contaminants in marine mammals yield representative details on contaminant burdens for chlorinated and... |
| Tipo: Manuscript |
Palavras-chave: Chemistry; Ecology; Earth & Environment. |
| Ano: 2007 |
URL: http://precedings.nature.com/documents/638/version/1 |
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| Maas, P.J.M.; Westra, L.Y.T.; Guerrero, S. Arias; Lobão, A.Q.; Scharf, U.; Zamora, N.A.; Erkens, R.H.J.. |
| A taxonomic revision of the genus Guatteria, including the former genera Guatteriella, Guatteriopsis and Heteropetalum is given. Within the genus Guatteria 177 species are recognized, 25 of which are new. Included are chapters on the history of the taxonomy of the genus, morphology, wood anatomy, karyology, palynology, chemistry, flower biology and pollination, dispersal, distribution and ecology, phylogeny and molecular studies, conservation, and uses. A synoptical key to all species is included, as well as two dichotomous keys, one for the species of Central America and Mexico, and one for the species of NE, E and SE Brazil. The species treatments include descriptions, full synonymy, geographical and ecological notes, vernacular names and taxonomic... |
| Tipo: Article / Letter to the editor |
Palavras-chave: Annonaceae; Chemistry; Descriptions; Flower biology and pollination; Guatteria; Guatteriella; Guatteriopsis; Heteropetalum; History; Molecular studies; Morphology; Neotropics; Palynology; Phylogeny; Taxonomy; Vernacular names. |
| Ano: 2015 |
URL: http://www.repository.naturalis.nl/record/588490 |
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| Sierra Rayne; Kaya Forest. |
| Organic carbon normalized soil and sediment-water partitioning (Koc) coefficients were estimated for all C1 through C8 perfluorinated alkylsulfonic acid (PFSA) and alkylcarboxylic acids (PFCA) congeners. The limited experimental Koc dataset for the straight chain C7 through C10 PFCAs and C8 and C10 PFSAs was correlated to SPARC and ALOGPS computationally estimated octanol-water partitioning constants and used to predict Koc values for both branched and linear C1 through C8 isomers. All branched and linear congeners in this homologue range are expected to have Koc values>1, leading to their accumulation in organic matter on sediments and soils, retardation during ground and pore water flow, and the preferential association with dissolved organic... |
| Tipo: Manuscript |
Palavras-chave: Chemistry; Earth & Environment. |
| Ano: 2009 |
URL: http://precedings.nature.com/documents/3011/version/1 |
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| Sierra Rayne; Kaya Forest. |
| Organic carbon normalized soil and sediment-water partitioning coefficients (K~oc~) were estimated for all C~1~ through C~8~ perfluoroalkyl carboxylic (PFCA) and sulfonic (PFSA) acid congeners. The limited experimental K~oc~ dataset for the straight chain C~7~ through C~10~ PFCAs and C~8~ and C~10~ PFSAs was correlated to SPARC and ALOGPS computationally estimated octanol-water partitioning / distribution constants and used to predict K~oc~ values for both branched and linear C~1~ through C~8~ isomers. Branched and linear congeners in this homologue range are generally expected to have K~oc~ values >1, leading to their accumulation in organic matter on sediments and soils, retardation during ground and pore water flow, and the preferential... |
| Tipo: Manuscript |
Palavras-chave: Chemistry; Earth & Environment. |
| Ano: 2009 |
URL: http://precedings.nature.com/documents/3011/version/2 |
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| Sierra Rayne; Kaya Forest; Ken J. Friesen. |
| We introduce a congener-specific numbering system for the C4 through C8 perfluorinated homologue groups of alkyl sulfonates, carboxylates, telomer alcohols and acids, and their derivatives. Increasing length of the carbon chain beyond C3 leads to a corresponding rapid increase in the number of potential isomers (C4 =4, C5 =8, C6 =17, C7 =39, and C8 =89 congeners). There is a need for clear and unambiguous chemical shorthand to ensure accuracy and consistency in the future perfluorinated alkyl substance (PFA) literature, and to correct previous misconceptions that may have restricted research efforts into developing full-congener PFA analysis. If adopted by the research community, introduction of a numbering system at this relatively early stage of... |
| Tipo: Poster |
Palavras-chave: Chemistry; Earth & Environment. |
| Ano: 2008 |
URL: http://precedings.nature.com/documents/1957/version/2 |
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| Sierra Rayne; Kaya Forest; Ken J. Friesen. |
| We introduce a congener-specific numbering system for the C4 through C8 perfluorinated homologue groups of alkyl sulfonates, carboxylates, telomer alcohols and acids, and their derivatives. Increasing length of the carbon chain beyond C3 leads to a corresponding rapid increase in the number of potential isomers (C4 =4, C5 =8, C6 =17, C7 =39, and C8 =89 congeners). There is a need for clear and unambiguous chemical shorthand to ensure accuracy and consistency in the future perfluorinated alkyl substance (PFA) literature, and to correct previous misconceptions that may have restricted research efforts into developing full-congener PFA analysis. If adopted by the research community, introduction of a numbering system at this relatively early stage of... |
| Tipo: Poster |
Palavras-chave: Chemistry; Earth & Environment. |
| Ano: 2008 |
URL: http://precedings.nature.com/documents/1957/version/1 |
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| Chen Wang. |
| The climate change believed by anthropogenic emission is not isolated but tightly coupled with other issues including biodiversity loss and ocean acidification etc., and in order to prevent the potential serious impacts, both political and technological methods are being tried for greenhouse mitigation. Dimming the income sunlight by some “geoengineering” approaches currently seem ruinously expensive and technically difficult, and would not prevent the increase of greenhouse gases (GHGs) in atmosphere and ocean acidification, so capturing carbon to reduce the environmental concentration of carbon dioxide (CO2) and promoting renewable energy development for the reduction of using fossil fuels are very necessary. Biofuels derived from... |
| Tipo: Manuscript |
Palavras-chave: Chemistry; Ecology; Earth & Environment. |
| Ano: 2010 |
URL: http://precedings.nature.com/documents/5161/version/1 |
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| Andreas Kukol. |
| In order to exploit the advantages of receptor-based virtual screening, namely time/cost saving and specificity, it is important to rely on algorithms that predict a high number of active ligands at the top ranks of a small molecule database. Towards that goal consensus methods combining the results of several docking algorithms were developed and compared against the individual algorithms. Furthermore, a recently proposed rescoring method based on drug efficiency indices was evaluated. Among AutoDock Vina 1.0, AutoDock 4.2 and GemDock, AutoDock Vina was the best performing single method in predicting high affinity ligands from a database of known ligands and decoys. The rescoring of predicted binding energies with the water/butanol partition coeffcient... |
| Tipo: Manuscript |
Palavras-chave: Biotechnology; Chemistry; Bioinformatics. |
| Ano: 2011 |
URL: http://precedings.nature.com/documents/5979/version/1 |
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| Elzobair, K.A.; Stromberger, M.E.; Ippolito, J.A.; Lentz, R.D.. |
| Biochar has been shown to increase microbial activity, alter microbial community structure, and increase soil fertility in arid and semi-arid soils, but at relatively high rates that may be impractical for large-scale field studies. This contrasts with organic amendments such as manure, which can be abundant and inexpensive if locally available, and thus can be applied to fields at greater rates than biochar. In a field study comparing biochar and manure, a fast pyrolysis hardwood biochar (10 tons per acre), dairy manure (19 tons per acre), a combination of biochar and manure at the aforementioned rates, or no amendment (control) was applied to an Aridisol (n=3) in fall 2008. Plots were annually cropped to corn. Surface soils (0-12 inches) were sampled... |
| Tipo: Article |
Palavras-chave: Chemistry; Fertility; Soil. |
| Ano: 2015 |
URL: http://eprints.nwisrl.ars.usda.gov/1599/1/1557.pdf |
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| Bradly Alicea. |
| The transduction and processing of physical information is becoming important in a range of research fields, from the design of materials and virtual environments to the dynamics of cellular microenvironments. Previous approaches such as morphological computation/soft robotics, neuromechanics, and embodiment have provided valuable insight. This work approaches haptic, proprioception, and physical sensing as all part of the same subject. In this presentation, three design criteria for applying physical intelligence to engineering applications will be presented. These criteria have several properties in common, which inspires two types of end-effector model: stochastic (based on a spring) and deterministic (based on a piezomechanical array). The generalized... |
| Tipo: Presentation |
Palavras-chave: Biotechnology; Chemistry; Molecular Cell Biology; Neuroscience. |
| Ano: 2011 |
URL: http://precedings.nature.com/documents/5910/version/1 |
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| J. Howard Bradbury; Chretienne Mandombi; D Nahimana; J. P. Banea; Ian C. Denton; N Kuwa. |
| Konzo is an upper motor neuron disease that causes irreversible paralysis of the legs mainly in children and young women^1,2^, due to consumption of large amounts of cyanogens from poorly processed cassava, the staple food of tropical Africa^3^. Konzo occurs in the Democratic Republic of Congo (DRC),Mozambique, Tanzania, Cameroon, Central African Republic and Angola. In March 2010 the wetting method, which removes cyanogens from cassava flour^4,5,6^, was taught to and used by the mothers of Kay Kalenge village. This reduced the total cyanide content of cassava flour to the FAO/WHO limit of 10ppm^7^. Cyanogen intake of school children, monitored by urinary thiocyanate analyses, decreased from mean values of 332 to 130 μmole/L. The percentage of... |
| Tipo: Manuscript |
Palavras-chave: Chemistry; Neuroscience; Plant Biology. |
| Ano: 2011 |
URL: http://precedings.nature.com/documents/6520/version/1 |
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| Anna Steindl; Thomas Strumpf; Frank Riepert. |
| The background of the project are claims of the EU regulation to generate reliable data considering the extent of copper contamination in soils of specialized crops in order to decide about copper restrictions in organic farming.

2522 single soil samples were collected on 85 vineyard and 13 hop areas with different management histories. Samples were taken from sites presently under cultivation, formerly cultivated, and sites without anthropogenic copper contamination as control, indicating natural background values. In addition to Aqua Regia extraction for determining total copper contents, available plant copper content was analyzed in NH~4~NO~3~ extraction. Soil parameters such as pH-value, C/N ratio, soil type etc.... |
| Tipo: Presentation |
Palavras-chave: Chemistry; Plant Biology. |
| Ano: 2011 |
URL: http://precedings.nature.com/documents/5737/version/1 |
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| Ippolito, J.A.; Barbarick, K.A.; Brobst, R.B.. |
| Predicting trace metal solid phase speciation changes associated with long-term biosolids land application is important for understanding and improving environmental quality. Biosolids were surface-applied (no incorporation; 0, 1, 2, 5, 10, and 15 tons per acre) to a semi-arid grassland in 1991 (single) or again in 2002 (repeated). In July 2003, soils were obtained from the 0-3, 3-6, and 6-12-inch depths in all plots. Using soil pH, soluble anion and cation concentrations from 0.01 moles per liter calcium chloride extractions, and dissolved organic carbon content, copper and zinc associated with minerals, hydrous ferric oxide, or dissolved organic phases was modeled using Visual Minteq. Scanning electron microscopy and energy dispersive x-ray analysis... |
| Tipo: Article |
Palavras-chave: Chemistry; Soil. |
| Ano: 2014 |
URL: http://eprints.nwisrl.ars.usda.gov/1556/1/1512.pdf |
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| Ippolito, J.A.. |
| Dairies utilize copper sulfate (CuSO4) foot baths to control hoof infections. Typical solutions are 5 or 10% CuSO4 (pH ~6), equal to 12,500 or 25,000 ppm Cu, respectively. When spent, hoof bath solutions are usually disposed of in waste lagoons and subsequently utilized for irrigation. In the Magic Valley, this practice appears to be causing soil Cu concentrations to increase. The goal of our research was to use local waste products to sequester Cu from a simulated hoof bath solution and to use waste products to adsorb excessive Cu from Cu-affected soils. |
| Tipo: Technical Bulletin |
Palavras-chave: Animal; Chemistry. |
| Ano: 2010 |
URL: http://eprints.nwisrl.ars.usda.gov/1365/1/1342.pdf |
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| Sierra Rayne; Kaya Forest. |
| Adiabatic ionization energy (AIE) calculations were performed at the AM1, PM3, PM6, PDDG, HF/QZVP, and B3LYP/QZVP levels of theory on 722 atmospherically relevant organic compounds with available experimental rate constants for atmospheric reactions with hydroxyl radicals (k~OH~). From the starting set of molecules, a final suite of 114 mono- and polyfunctionalized compounds provided converged neutral and cationic geometries without imaginary frequencies for all six levels of theory. NIST evaluated AIEs were available for 54 compounds, providing mean absolute AIE prediction errors of 0.31 (AM1), 0.28 (PM3), 0.50 (PM6), 0.36 (PDDG), 1.22 (HF/QZVP), and 0.20 eV (B3LYP/QZVP). Modest correlations were found between the experimental (r=-0.68, SE=0.81) and... |
| Tipo: Manuscript |
Palavras-chave: Chemistry; Earth & Environment. |
| Ano: 2010 |
URL: http://precedings.nature.com/documents/5447/version/1 |
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| Registros recuperados: 601 | |
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