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Qun Huo; Shannon Sullivan; Hillari Hallquist; Sally Litherland; David Decker; Inoel Rivera-Ramirez. |
Prostate cancer (PCa) is the most common malignancy and the second leading cause of cancer death in American men. Due to the lack of accurate tests to distinguish aggressive cancer from indolent tumor, prostate cancer is often over-treated. Post-surgery pathology analysis revealed that 30% of tumors removed by radical prostatectomy are deemed clinically insignificant and would not have required such invasive treatment.^1^ Over-diagnosis and treatment of low-risk prostate cancer has serious and long-lasting side effect: as high as 70% of the patients who receive radical prostatectomy treatment will suffer a loss of sexual potency that cannot be remedied by drugs such as sildenafil citrate.^2^ We herein report a simple nanoparticle-serum protein adsorption... |
Tipo: Manuscript |
Palavras-chave: Biotechnology; Cancer; Chemistry. |
Ano: 2011 |
URL: http://precedings.nature.com/documents/6409/version/1 |
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Katja Neubauer; Jenny Bandomir; Anett Grunenberg; Andreas Müller; Udo Kragl; Kerstin Schmidt. |
With the environmental risk assessment (ERA) for genetically modified plants (GMP) the identification of equivalence or differences in the composition of ingredients of GMPs and non-GMPs has to be investigated. The strategy is based upon the idea that traditionally cultivated crops have been used safely for many years, thus every divergence within the compounds of a GMP in contrast to its non-GMP counterpart could refer to a risk and has to be further analysed.

The BioOK company offers the opportunity to analyse very different aspects from the ERA of GMPs in one hand. Beside toxicological analysis and the determination of environmental effects via soil analysis, we can look into several plant metabolites to identify... |
Tipo: Poster |
Palavras-chave: Biotechnology; Chemistry; Plant Biology. |
Ano: 2010 |
URL: http://precedings.nature.com/documents/4439/version/1 |
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Omar Yepez. |
The hypertorus electron model is applied to the chemical bond. As a consequence, the bond topology can be determined. A linear correlation is found between the normalized bond area and the bond energy. The normalization number is a whole number. This number is interpreted as the Lewis's electron pair. A new electron distribution in the molecule follows. This discovery prompts to review the chemical bond, as it is understood in chemistry and physics. |
Tipo: Manuscript |
Palavras-chave: Chemistry. |
Ano: 2010 |
URL: http://precedings.nature.com/documents/5336/version/1 |
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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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Sierra Rayne; Kaya Forest. |
Gas phase constant pressure heat capacities (C~p,gas~) for the C~1~ through C~10~ straight chain alkanes, isobutane, hydrogen atom, hydroxyl and methyl radicals, and water were calculated between 298.15 and 1500 K using various low (semiempirical PM6) through high level (CBS-Q//B3 and G4 composite) theoretical methods. All levels of theory provided good agreement with experimental C~p,gas~ data (<+/-10% deviation) regardless of molecular size. A modest but progressive loss of C~p,gas~ predictive accuracy occurs with increasing molecular size among the n-alkanes. For most compounds at all levels of theory, the highest C~p,gas~ estimation accuracy occurs at elevated temperatures, with decreasing accuracy as the temperature is lowered or raised about... |
Tipo: Manuscript |
Palavras-chave: Chemistry. |
Ano: 2010 |
URL: http://precedings.nature.com/documents/5024/version/1 |
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Kikuo Harigaya. |
1. Topological materials: Moebius nanographite and conjugated polymers
2. Magnetic domain wall states [1] vs. helical magmetic order in nanographite [2]
3. Static polarizability [alpha] and the first hyperpolarizability [beta] are studied, comparing three models: Mobius strip cyclacene, ring cyclacene, and linear strip.
4. Opening the knot of the Mobius to form the ring leads to the increase of [alpha] from 268 to 323 a.u. and [beta] increases about three times from 393 to 1049 a.u.
5. Opening the ring to form the linear strip, [alpha] increases from 323 to 476 a.u. [beta] as well increases about three times from 1049 to 2814 a.u.

[1] K. Wakabayashi and... |
Tipo: Presentation |
Palavras-chave: Chemistry. |
Ano: 2009 |
URL: http://precedings.nature.com/documents/3881/version/1 |
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Jian-She Yang; Bo-Zhang Yu; Wen-Xin Li. |
Radiotherapy plays a very important role in cancer treatment. Radiosensitizers have been widely used to enhance the radiosensitivity of cancer cells at given radiations. Here we fabricate multi-walled carbon nanotubes with ammonium persulfate, and get very short samples with 30-50 nanometer length. Cell viability assay show that f-WCNTs induce cell death significantly. We hypothesize that free radicals originated from hydroxyl and carbonyl groups on the surface of f-WCNTs lead cell damage. |
Tipo: Manuscript |
Palavras-chave: Biotechnology; Cancer; Chemistry. |
Ano: 2007 |
URL: http://precedings.nature.com/documents/1421/version/1 |
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Susumu Morimoto. |
If biologists can utilize a table to have access to biological phenomena in the manner analogous to the periodic table for chemical elements, they may get hold of a directing post in life science. Currently the mutational rule of influenza viruses have remained perplexed and to reveal it should be now desired when avian influenza virus has just then threatened human beings. Here I examine the applicability of a novel periodic table for the genetic code to influenza A/H3N2 virus, while presenting two rules regarding single point mutations of its virus hemagglutinin gene. One rule is that non-synonymous single point mutations are intimately associated with the first or second base replacements between four groups (5, 6, 9, and 10) in the periodic table.... |
Tipo: Manuscript |
Palavras-chave: Chemistry; Genetics & Genomics; Evolutionary Biology. |
Ano: 2007 |
URL: http://precedings.nature.com/documents/428/version/1 |
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Lazhar Mhadhbi; Jose Fumega; Moncef Boumaiza; Ricardo Beiras. |
A new toxic menace, polybrominated diphenyl ethers (PBDEs), is being detected in the aquatic environment all over the world. The environmental presence of PBDEs and its entry into the environment as BDE-47 and -99 make quality aquatic toxicity data necessary to assess the aquatic hazard risk of PBDs. This study examines the effects of three PBDE-47 and -99 on embryo and larval stages of the marine flatfish turbot (_Psetta maxima_). The acute toxicity of the three PBDEs was examined and NOEC, LOEC, LC10 and LC50 were calculated. All tested compounds caused lethal as well as nonlethal malformations during embryo development. The effects of PBDEs in the different life stages of turbot were analysed. PBDEs seemed to be teratogenic at concentrations higher than... |
Tipo: Manuscript |
Palavras-chave: Chemistry; Ecology; Earth & Environment. |
Ano: 2010 |
URL: http://precedings.nature.com/documents/4656/version/1 |
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Rakesh Sharma. |
MRI combined with MR spectroscopy generates better information of both brain tissue composition and mesurement of metabolites or neurochemicals in multiple sclerosis(MS), Alzheimer's disease and epilepsy. New fast imaging techniques are technical advance in visualizing accurate anatomy and measurement of absolute neurochemicals in brain. Gray metter seated MS lesions is a new form of disease and lesion may appear normal on MRI but show spectroscopy peaks. High magnetic field scanners are available for fast imaging. |
Tipo: Presentation |
Palavras-chave: Biotechnology; Chemistry; Neuroscience; Bioinformatics. |
Ano: 2010 |
URL: http://precedings.nature.com/documents/4317/version/1 |
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Sierra Rayne; Kaya Forest. |
New experimental data is available in the literature regarding the octanol-water distribution behavior of representative straight chain perfluoroalkyl carboxylate (PFCA) and sulfonate (PFSA) congeners. The current study provides the first investigation into the predictive ability of various software programs for estimating the corresponding octanol-water partitioning (log P) and distribution (log D) constants of PFCAs and PFSAs. Wide predictive variation was found within and between the various methods. Several programs were able to accurately estimate the log P/D fragmental contributions of a -CF~2~- group for PFCAs, as well as the associated Gibbs free energies for partitioning into octanol from water due to the hydrophobic character of the... |
Tipo: Manuscript |
Palavras-chave: Chemistry; Earth & Environment. |
Ano: 2009 |
URL: http://precedings.nature.com/documents/3282/version/2 |
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Regalado, E.L.; Rodríguez, M.; Menéndez, R.; Concepción, A.A.; Nogueiras, C.; Laguna, A.; Rodríguez, A.A.; Williams, D.E.; Lenzo-Luaces, P.; Valdés, O.; Hernandez, Y.. |
Daily topical application of the aqueous ethanolic extract of the marine sea grass, Thalassia testudinum, on mice skin exposed to UVB radiation resulted in a dose dependent recovery of the skin macroscopic alterations over a 6-day period. Maximal effect (90%) occurred at a dose of 240 μg/cm2, with no additional effects at higher doses. Bioassay-guided fractionation of the plant extract resulted in the isolation of thalassiolin B (1). Topical application of 1 (240 μg/cm2) markedly reduces skin UVB-induced damage. In addition, thalassiolin B scavenged 2,2-diphenyl-2-picrylhydrazyl radical with an EC50=100 μg/ml. These results suggest that thalassiolin B is responsible for the skin regenerating effects of the crude extract of T. testudinum |
Tipo: Journal Contribution |
Palavras-chave: Chemistry; Pharmacology; Chemistry; Pharmacology; Http://aims.fao.org/aos/agrovoc/c_1522; Http://aims.fao.org/aos/agrovoc/c_5760. |
Ano: 2009 |
URL: http://hdl.handle.net/1834/3865 |
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Regalado, E.L.; Laguna, A.; Mendiola, J.; Thomas, O.P.; Nogueiras, C.. |
Bioguided fractionation of Agelas cerebrum crude extract resulted in isolation of four bromopyrrole and four bromopyrrole aminoimidazole alkaloids, identified as 5-bromopyrrole-2-carboxylic acid (1), 4-bromopyrrole-2-carboxylic acid (2), 3,4-bromopyrrole-2-carboxylic acid (3), 4,5-bromopyrrole-2-carboxylic acid (4), oroidin (5), bromoageliferin (6), dibromoageliferin (7) and dibromosceptrin (8) on the basis of spectroscopic data analyses (UV, IR, HRMS, 1D and 2D NMR) and comparison with literature data. This is the first report of compounds 2 and 3 in a marine sponge belonging to the Agelas genus and the first evidence of the presence of 1 from a natural source. |
Tipo: Journal Contribution |
Palavras-chave: Alkaloids; Sponges; Chemistry; Chemistry; Alkaloids; Sponges; Http://aims.fao.org/aos/agrovoc/c_1522; Http://aims.fao.org/aos/agrovoc/c_269; Http://aims.fao.org/aos/agrovoc/c_7321. |
Ano: 2010 |
URL: http://hdl.handle.net/1834/3862 |
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Martínez Canals, M.; Montalvo, J.F.; Miravet, M.E.; Lugioyo, M.; Loza, S.; Pérez, R.; García, I.; Rodríguez, A.; Cesar, M.E.; Esponda, S.; Sánchez, M.; Delgado, V.. |
The anthropogenic affectation was evaluated on the coast N of the Gulf of Batabanó in May 2003 (corresponding to the provinces of Matanzas and Havana), in areas located in the line of the coast. The results were compared with the historical information of the sector. In the coast N and the Ensenada of the Broa, the parameters oxygen saturation, DBO5 and DQO showed characteristic high values of eutrofication. The biggest contribution in the Cianoficies was in the near coastal areas to sources of organic contamination. In the case of the nutrients they show specific data of mesothrofic waters with tendency to the eutrofization and the silts presented a high affectation for toxic metals. The area near to Guanímar is distinguished to present conditions of... |
Tipo: Proceedings Paper |
Palavras-chave: Phytoplankton; Water quality; Primary production; Chemistry; Environmental monitoring; Phytoplankton; Water quality; Primary production; Chemistry; Environmental monitoring; Http://aims.fao.org/aos/agrovoc/c_13344; Http://aims.fao.org/aos/agrovoc/c_16061; Http://aims.fao.org/aos/agrovoc/c_34329; Http://aims.fao.org/aos/agrovoc/c_1522; Http://aims.fao.org/aos/agrovoc/c_37876. |
Ano: 2006 |
URL: http://hdl.handle.net/1834/2172 |
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Meysman, F.. |
Within the natural sciences, it has long been recognized that biological activity can modify the texture, structure and composition of surface sediments. Darwin (1881) already examined the stirring of soils by burrowing earthworms and made detailed observations on how these organisms affect soil processes. A similar phenomenon can be observed in aquatic sediments, which are inhabited by a diverse biological community, supported by the flux of organic matter and oxygen from the overlying water column. Surface sediments of oceans, estuaries, lakes and rivers are highly active biogeochemical environments and an effective way to generate insight in the complexity of the interactions is by means of so-called general early diagenetic models (e.g. Soetaert et al,... |
Tipo: Info:eu-repo/semantics/doctoralThesis |
Palavras-chave: Chemistry; Ecology; Hydrology; Model; Sediment; Water. |
Ano: 2001 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=8063 |
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Registros recuperados: 601 | |
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