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Sample records for analysis chemical species

  1. Nature and Analysis of Chemical Species.

    ERIC Educational Resources Information Center

    Shuman, Mark S.; Fogleman, Wavell W.

    1978-01-01

    Presents a literature review of the nature and analysis of chemical species in water, covering publications of 1976-77. This review is concerned with inorganics, and it covers: (1) electrochemical analysis; (2) spectroscopy; (3) neutron activation, radiochemical analysis, and isotope dilution. A list of 262 references is also presented. (HM)

  2. Nature and Analysis of Chemical Species.

    ERIC Educational Resources Information Center

    Shuman, Mark S.; Fogleman, Wavell W.

    1978-01-01

    Presents a literature review of the nature and analysis of chemical species in water, covering publications of 1976-77. This review is concerned with inorganics, and it covers: (1) electrochemical analysis; (2) spectroscopy; (3) neutron activation, radiochemical analysis, and isotope dilution. A list of 262 references is also presented. (HM)

  3. Chemical analysis of molecular species through turbid medium.

    PubMed

    Arora, Rajan; Petrov, Georgi I; Yakovlev, Vladislav V; Scully, Marlan O

    2014-02-04

    Subsurface analysis of chemical species is imperative for biomedical diagnostics and imaging, homeland security, and pharmaceutical and other industries; however, the access to the object of interest is often obscured by an optically scattering medium which limits the ability to inspect the chemical composition of the sample. In this report, we employ coherent Raman microspectroscopy in a combination with a hierarchical cluster analysis to mitigate the effect of scattering and demonstrate the identification of multiple chemical species.

  4. Substantial equivalence analysis in fruits from three Theobroma species through chemical composition and protein profiling.

    PubMed

    Pérez-Mora, Walter; Jorrin-Novo, Jesús V; Melgarejo, Luz Marina

    2018-02-01

    Substantial equivalence studies were performed in three Theobroma spp., cacao, bicolor and grandiflorum through chemical composition analysis and protein profiling of fruit (pulp juice and seeds). Principal component analysis of sugar, organic acid, and phenol content in pulp juice revealed equivalence among the three species, with differences in some of the compounds that may result in different organoleptic properties. Proteins were extracted from seeds and pulp juice, resolved by two dimensional electrophoresis and major spots subjected to mass spectrometry analysis and identification. The protein profile, as revealed by principal component analysis, was variable among the three species in both seed and pulp, with qualitative and quantitative differences in some of protein species. The functional grouping of the identified proteins correlated with the biological role of each organ. Some of the identified proteins are of interest, being minimally discussed, including vicilin, a protease inhibitor, and a flavonol synthase/flavanone 3-hydroxylase. Theobroma grandiflorum and Theobroma bicolor are endemic Amazonian plants that are poorly traded at the local level. As close relatives of Theobroma cacao, they may provide a good alternative for human consumption and industrial purposes. In this regard, we performed equivalence studies by conducting a comparative biochemical and proteomics analysis of the fruit, pulp juice and seeds of these three species. The results indicated equivalent chemical compositions and variable protein profiles with some differences in the content of the specific compounds or protein species that may result in variable organoleptic properties between the species and can be exploited for traceability purposes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Plant seed species identification from chemical fingerprints: a high-throughput application of direct analysis in real time mass spectrometry.

    PubMed

    Lesiak, Ashton D; Cody, Robert B; Dane, A John; Musah, Rabi A

    2015-09-01

    Plant species identification based on the morphological features of plant parts is a well-established science in botany. However, species identification from seeds has largely been unexplored, despite the fact that the seeds contain all of the genetic information that distinguishes one plant from another. Using seeds of genus Datura plants, we show here that the mass spectrum-derived chemical fingerprints for seeds of the same species are similar. On the other hand, seeds from different species within the same genus display distinct chemical signatures, even though they may contain similar characteristic biomarkers. The intraspecies chemical signature similarities on the one hand, and interspecies fingerprint differences on the other, can be processed by multivariate statistical analysis methods to enable rapid species-level identification and differentiation. The chemical fingerprints can be acquired rapidly and in a high-throughput manner by direct analysis in real time mass spectrometry (DART-MS) analysis of the seeds in their native form, without use of a solvent extract. Importantly, knowledge of the identity of the detected molecules is not required for species level identification. However, confirmation of the presence within the seeds of various characteristic tropane and other alkaloids, including atropine, scopolamine, scopoline, tropine, tropinone, and tyramine, was accomplished by comparison of the in-source collision-induced dissociation (CID) fragmentation patterns of authentic standards, to the fragmentation patterns observed in the seeds when analyzed under similar in-source CID conditions. The advantages, applications, and implications of the chemometric processing of DART-MS derived seed chemical signatures for species level identification and differentiation are discussed.

  6. Discrimination and chemical phylogenetic study of seven species of Dendrobium using infrared spectroscopy combined with cluster analysis

    NASA Astrophysics Data System (ADS)

    Luo, Congpei; He, Tao; Chun, Ze

    2013-04-01

    Dendrobium is a commonly used and precious herb in Traditional Chinese Medicine. The high biodiversity of Dendrobium and the therapeutic needs require tools for the correct and fast discrimination of different Dendrobium species. This study investigates Fourier transform infrared spectroscopy followed by cluster analysis for discrimination and chemical phylogenetic study of seven Dendrobium species. Despite the general pattern of the IR spectra, different intensities, shapes, peak positions were found in the IR spectra of these samples, especially in the range of 1800-800 cm-1. The second derivative transformation and alcoholic extracting procedure obviously enlarged the tiny spectral differences among these samples. The results indicated each Dendrobium species had a characteristic IR spectra profile, which could be used to discriminate them. The similarity coefficients among the samples were analyzed based on their second derivative IR spectra, which ranged from 0.7632 to 0.9700, among the seven Dendrobium species, and from 0.5163 to 0.9615, among the ethanol extracts. A dendrogram was constructed based on cluster analysis the IR spectra for studying the chemical phylogenetic relationships among the samples. The results indicated that D. denneanum and D. crepidatum could be the alternative resources to substitute D. chrysotoxum, D. officinale and D. nobile which were officially recorded in Chinese Pharmacopoeia. In conclusion, with the advantages of high resolution, speediness and convenience, the experimental approach can successfully discriminate and construct the chemical phylogenetic relationships of the seven Dendrobium species.

  7. Phytotoxic effects and chemical analysis of leaf extracts from three Phytolaccaceae species in South Korea.

    PubMed

    Kim, Yong Ok; Johnson, Jon D; Lee, Eun Ju

    2005-05-01

    We analyzed phenolic compounds and other elements in leaf extracts and compared morphology of three species of the Phytolaccaceae family found in South Korea. To test allelochemical effects of the three Phytolacca species, we also examined seed germination and dry weight of seedlings of Lactuca indica and Sonchus oleraceus treated with leaf extracts. The concentrations of total phenolic compounds were exotic Phytolacca esculenta (3.9 mg/l), native Phytolacca insularis (4.4 mg/l), and exotic Phytolacca americana (10.2 mg/l). There was no significant difference in concentrations between P. esculenta and P. insularis, but the concentration of total phenolics in P. americana was two times higher than either P. esculenta or P. insularis. Analysis of aqueous extracts by HPLC showed seven phenolic compounds (gallic acid, protocatechuic acid, chlorogenic acid, caffeic acid, m-hydroxybenzoic acid, p-coumaric acid, and cinnamic acid). Total phenolics in P. americana were eight to 16 times higher than either P. esculenta or P. insularis, respectively. P. americana inhibited seed germination and dry weight of the two assay species. The phytotoxic effects of the two Phytolacca species were different, despite the fact that P. esculenta and P. insularis had similar levels of total phenolic compounds. We also found that P. americana had invaded Ullung Island, which suggested that P. americana had excellent adaptability to the environment. The three species of Phytolaccaceae in South Korea can be distinguished by their different allelopathic potentials and morphologies.

  8. Chemical Species, Micromorphology, and XRD Fingerprint Analysis of Tibetan Medicine Zuotai Containing Mercury

    PubMed Central

    Li, Cen; Yang, Hongxia; Xiao, Yuancan; Zhandui; Sanglao; Wang, Zhang; Ladan, Duojie; Bi, Hongtao

    2016-01-01

    Zuotai (gTso thal) is one of the famous drugs containing mercury in Tibetan medicine. However, little is known about the chemical substance basis of its pharmacodynamics and the intrinsic link of different samples sources so far. Given this, energy dispersive spectrometry of X-ray (EDX), scanning electron microscopy (SEM), atomic force microscopy (AFM), and powder X-ray diffraction (XRD) were used to assay the elements, micromorphology, and phase composition of nine Zuotai samples from different regions, respectively; the XRD fingerprint features of Zuotai were analyzed by multivariate statistical analysis. EDX result shows that Zuotai contains Hg, S, O, Fe, Al, Cu, and other elements. SEM and AFM observations suggest that Zuotai is a kind of ancient nanodrug. Its particles are mainly in the range of 100–800 nm, which commonly further aggregate into 1–30 μm loosely amorphous particles. XRD test shows that β-HgS, S8, and α-HgS are its main phase compositions. XRD fingerprint analysis indicates that the similarity degrees of nine samples are very high, and the results of multivariate statistical analysis are broadly consistent with sample sources. The present research has revealed the physicochemical characteristics of Zuotai, and it would play a positive role in interpreting this mysterious Tibetan drug. PMID:27738409

  9. Project VeSElkA: abundance analysis of chemical species in HD 41076 and HD 148330

    NASA Astrophysics Data System (ADS)

    Khalack, V.; Gallant, G.; Thibeault, C.

    2017-10-01

    A new semi-automatic approach is employed to carry out the abundance analysis of high-resolution spectra of HD 41076 and HD 148330 obtained recently with the spectropolarimetre Echelle SpectroPolarimetric Device for Observations of Stars at the Canada-France-Hawaii Telescope. This approach allows to prepare in a semi-automatic mode the input data for the modified zeeman2 code and to analyse several hundreds of line profiles in sequence during a single run. It also provides more information on abundance distribution for each chemical element at the deeper atmospheric layers. Our analysis of the Balmer profiles observed in the spectra of HD 41076 and HD 148330 has resulted in the estimates of their effective temperature, gravity, metallicity and radial velocity. The respective models of stellar atmosphere have been calculated with the code phoenix and used to carry out abundance analysis employing the modified zeeman2 code. The analysis shows a deficit of the C, N, F, Mg, Ca, Ti, V, Cu, Y, Mo, Sm and Gd, and overabundance of Cr, Mn, Fe, Co, Ni, Sr, Zr, Ba, Ce, Nd and Dy in the stellar atmosphere of HD 41076. In the atmosphere of HD 148330, the C, N and Mo appear to be underabundant, while the Ne, Na, Al, Si, P, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, Sr, Y, Zr, Ba, Ce, Pr, Nd, Sm, Eu, Gd and Dy are overabundant. We also have found signatures of vertical abundance stratification of Fe, Ti, Cr and Mn in HD 41076, and of Fe, Ti, V, Cr, Mn, Y, Zr, Ce, Nd, Sm and Gd in HD 148330.

  10. Methods of chemical analysis for selected species in marble and limestone surfaces exposed to the acidic outdoor environment

    SciTech Connect

    Jensen, K.J.; Williams, F.L.; Huff, E.A.; Youngdahl, C.A.

    1986-03-01

    There is concern for marble and limestone exposed to the acidic outdoor environment because they are widely used as the exterior structures of buildings and monuments and because the calcium carbonate stones are especially sensitive to acid. Field tests of these building materials under carefully monitored environmental conditions are being conducted to measure damage rates and ultimately to quantify the individual effects of the important damage mechanisms. The development of further quantitative understanding will provide an improved basis for control strategies. The demonstration, verification, and application of a technique to measure selected surface anionic and cationic species are important contributions to this study. These methods of stone surface chemical analysis, developed for and applied in the National Acid Precipitation Assessment Program (NAPAP), are appropriate to monitor selected species of program interest and are sufficient to determine surface sulfate and nitrate reaction products.

  11. Chemical Constituents Analysis and Antidiabetic Activity Validation of Four Fern Species from Taiwan

    PubMed Central

    Chen, Chen-Yu; Chiu, Fu-Yu; Lin, Yenshou; Huang, Wei-Jan; Hsieh, Po-Shiuan; Hsu, Feng-Lin

    2015-01-01

    Pterosins are abundant in ferns, and pterosin A was considered a novel activator of adenosine monophosphate-activated protein kinase, which is crucial for regulating blood glucose homeostasis. However, the distribution of pterosins in different species of ferns from various places in Taiwan is currently unclear. To address this question, the distribution of pterosins, glucose-uptake efficiency, and protective effects of pterosin A on β-cells were examined. Our results showed that three novel compounds, 13-chloro-spelosin 3-O-β-d-glucopyranoside (1), (3R)-Pterosin D 3-O-β-d-(3'-p-coumaroyl)-glucopyranoside (2), and (2R,3R)-Pterosin L 3-O-β-d-(3'-p-coumaroyl)-glucopyranoside (3), were isolated for the first time from four fern species (Ceratopteris thalictroides, Hypolepis punctata, Nephrolepis multiflora, and Pteridium revolutum) along with 27 known compounds. We also examined the distribution of these pterosin compounds in the mentioned fern species (except N. multiflora). Although all pterosin analogs exhibited the same effects in glucose uptake assays, pterosin A prevented cell death and reduced reactive oxygen species (ROS) production. This paper is the first report to provide new insights into the distribution of pterosins in ferns from Taiwan. The potential anti-diabetic activity of these novel phytocompounds warrants further functional studies. PMID:25622260

  12. Chemical constituents analysis and antidiabetic activity validation of four fern species from Taiwan.

    PubMed

    Chen, Chen-Yu; Chiu, Fu-Yu; Lin, Yenshou; Huang, Wei-Jan; Hsieh, Po-Shiuan; Hsu, Feng-Lin

    2015-01-22

    Pterosins are abundant in ferns, and pterosin A was considered a novel activator of adenosine monophosphate-activated protein kinase, which is crucial for regulating blood glucose homeostasis. However, the distribution of pterosins in different species of ferns from various places in Taiwan is currently unclear. To address this question, the distribution of pterosins, glucose-uptake efficiency, and protective effects of pterosin A on β-cells were examined. Our results showed that three novel compounds, 13-chloro-spelosin 3-O-β-d-glucopyranoside (1), (3R)-Pterosin D 3-O-β-d-(3'-p-coumaroyl)-glucopyranoside (2), and (2R,3R)-Pterosin L 3-O-β-d-(3'-p-coumaroyl)-glucopyranoside (3), were isolated for the first time from four fern species (Ceratopteris thalictroides, Hypolepis punctata, Nephrolepis multiflora, and Pteridium revolutum) along with 27 known compounds. We also examined the distribution of these pterosin compounds in the mentioned fern species (except N. multiflora). Although all pterosin analogs exhibited the same effects in glucose uptake assays, pterosin A prevented cell death and reduced reactive oxygen species (ROS) production. This paper is the first report to provide new insights into the distribution of pterosins in ferns from Taiwan. The potential anti-diabetic activity of these novel phytocompounds warrants further functional studies.

  13. The proposed biosynthesis of procyanidins by the comparative chemical analysis of five Camellia species using LC-MS

    PubMed Central

    Zhang, Liang; Tai, Yuling; Wang, Yijun; Meng, Qilu; Yang, Yunqiu; Zhang, Shihua; Yang, Hua; Zhang, Zhengzhu; Li, Daxiang; Wan, Xiaochun

    2017-01-01

    The genus Camellia (C.) contains many species, including C. sinensis, C. assamica, and C. taliensis, C. gymnogyna and C. tachangensis. The polyphenols of C. sinensis and C. assamica are flavan-3-ols monomers and their dimers and trimmers. However, the biosynthesis of procyanidins in Camellia genus remains unclear. In the present study, a comparative chemical analysis of flavan-3-ols, flavan-3-ols glycoside and procyanidins was conducted by high performance liquid chromatography (HPLC) and liquid chromatography diode array detection coupled with triple-quadrupole mass-spectrometry (LC-DAD-QQQ-MS). The results showed that C. tachangensis had a significant higher contents of (-)-epicatechin (EC) and (-)-epigallocatechin (EGC) compared with C. sinensis (p < 0.001). By contrast, higher levels of galloylated catechins were detected in C. sinensis. LC-DAD-MS/MS indicated that the main secondary metabolites of C. tachangensis were non-galloylated catechins, procyanidin dimers and trimers. Furthermore, (-)-epicatechin glucose (EC-glucose) and (-)-epigallocatechin glucose (EGC-glucose) were also abundant in C. tachangensis. A correlation analysis of EC-glucose and procyanidins dimers was conducted in five Camellia species. The levels of EC-glucose were closely related to the procyanidin dimers content. Thus, it was suggested that EC-glucose might be an important substrate for the biosynthesis of procyanidins. PMID:28383067

  14. Comparison of two officinal Chinese pharmacopoeia species of Ganoderma based on chemical research with multiple technologies and chemometrics analysis.

    PubMed

    Da, Juan; Wu, Wan-Ying; Hou, Jin-Jun; Long, Hua-Li; Yao, Shuai; Yang, Zhou; Cai, Lu-Ying; Yang, Min; Jiang, Bao-Hong; Liu, Xuan; Cheng, Chun-Ru; Li, Yi-Feng; Guo, De-An

    2012-01-27

    To investigate the chemical differences between Ganoderma lucidum (G. lucidum, Chizhi) and Ganoderma sinense (G. sinense, Zizhi). Thirty two batches of commercial Ganoderma samples were collected, including 20 batches of G. lucidum and 12 batches of G. sinense cultivated in different geographical regions. Chemical substances in aqueous extract and alcoholic extract, mainly polysaccharides and triterpenes respectively, were investigated. Determination of polysaccharides was carried out with a high performance liquid chromatography with an variable wavelength detector. Meanwhile, analysis of triterpenes were performed on an ultraviolet spectrophotometer, an ultra performance liquid chromatography and a rapid resolution liquid chromatograph combined with an electrospray ionization mass spectrometer. Chromatograms and spectra for all batches and reference standards of main components were obtained and used for direct comparison. Further discussion was made on the basis of the result of principal component analysis (PCA). Significant difference of triterpenes was shown between G. lucidum and G. sinense. In 20 batches of G. lucidum, 12 main components, including eight ganoderic acids and four ganoderenic acids were identified and ten of them were quantitatively determined, with the total content from 0.249% to 0.690%. However, none of those triterpenes was found in either batch of G. sinense. As for constituents of polysaccharides, seven monosaccharides were identified and four main components among them were quantitatively determined. Difference of polysaccharides was not directly observed, but latent information was revealed by PCA and the discrimination became feasible. G. lucidum and G. sinense were chemically different, which might result in pharmacological distinction. Preparations of traditional Chinese medicine (TCM) from Ganoderma should make accurate specification on the origin of species. Copyright © 2011 Elsevier B.V. All rights reserved.

  15. Chromatographic speciation of Cr(III)-species, inter-species equilibrium isotope fractionation and improved chemical purification strategies for high-precision isotope analysis

    PubMed Central

    Larsen, K.K.; Wielandt, D.; Schiller, M.; Bizzarro, M.

    2016-01-01

    Chromatographic purification of chromium (Cr), which is required for high-precision isotope analysis, is complicated by the presence of multiple Cr-species with different effective charges in the acid digested sample aliquots. The differing ion exchange selectivity and sluggish reaction rates of these species can result in incomplete Cr recovery during chromatographic purification. Because of large mass-dependent inter-species isotope fractionation, incomplete recovery can affect the accuracy of high-precision Cr isotope analysis. Here, we demonstrate widely differing cation distribution coefficients of Cr(III)-species (Cr3+, CrCl2+ and CrCl2+) with equilibrium mass-dependent isotope fractionation spanning a range of ~1‰/amu and consistent with theory. The heaviest isotopes partition into Cr3+, intermediates in CrCl2+ and the lightest in CrCl2+/CrCl3°. Thus, for a typical reported loss of ~25% Cr (in the form of Cr3+) through chromatographic purification, this translates into 185 ppm/amu offset in the stable Cr isotope ratio of the residual sample. Depending on the validity of the mass-bias correction during isotope analysis, this further results in artificial mass-independent effects in the mass-bias corrected 53Cr/52Cr (μ53 Cr* of 5.2 ppm) and 54Cr/52Cr (μ54Cr* of 13.5 ppm) components used to infer chronometric and nucleosynthetic information in meteorites. To mitigate these fractionation effects, we developed strategic chemical sample pre-treatment procedures that ensure high and reproducible Cr recovery. This is achieved either through 1) effective promotion of Cr3+ by >5 days exposure to HNO3 —H2O2 solutions at room temperature, resulting in >~98% Cr recovery for most types of sample matrices tested using a cationic chromatographic retention strategy, or 2) formation of Cr(III)-Cl complexes through exposure to concentrated HCl at high temperature (>120 °C) for several hours, resulting in >97.5% Cr recovery using a chromatographic elution strategy that

  16. Chromatographic speciation of Cr(III)-species, inter-species equilibrium isotope fractionation and improved chemical purification strategies for high-precision isotope analysis.

    PubMed

    Larsen, K K; Wielandt, D; Schiller, M; Bizzarro, M

    2016-04-22

    Chromatographic purification of chromium (Cr), which is required for high-precision isotope analysis, is complicated by the presence of multiple Cr-species with different effective charges in the acid digested sample aliquots. The differing ion exchange selectivity and sluggish reaction rates of these species can result in incomplete Cr recovery during chromatographic purification. Because of large mass-dependent inter-species isotope fractionation, incomplete recovery can affect the accuracy of high-precision Cr isotope analysis. Here, we demonstrate widely differing cation distribution coefficients of Cr(III)-species (Cr(3+), CrCl(2+) and CrCl2(+)) with equilibrium mass-dependent isotope fractionation spanning a range of ∼1‰/amu and consistent with theory. The heaviest isotopes partition into Cr(3+), intermediates in CrCl(2+) and the lightest in CrCl2(+)/CrCl3°. Thus, for a typical reported loss of ∼25% Cr (in the form of Cr(3+)) through chromatographic purification, this translates into 185 ppm/amu offset in the stable Cr isotope ratio of the residual sample. Depending on the validity of the mass-bias correction during isotope analysis, this further results in artificial mass-independent effects in the mass-bias corrected (53)Cr/(52)Cr (μ(53)Cr* of 5.2 ppm) and (54)Cr/(52)Cr (μ(54)Cr* of 13.5 ppm) components used to infer chronometric and nucleosynthetic information in meteorites. To mitigate these fractionation effects, we developed strategic chemical sample pre-treatment procedures that ensure high and reproducible Cr recovery. This is achieved either through 1) effective promotion of Cr(3+) by >5 days exposure to HNO3H2O2 solutions at room temperature, resulting in >∼98% Cr recovery for most types of sample matrices tested using a cationic chromatographic retention strategy, or 2) formation of Cr(III)-Cl complexes through exposure to concentrated HCl at high temperature (>120 °C) for several hours, resulting in >97.5% Cr recovery using a

  17. Comparison of two freshwater turtle species as monitors of radionuclide and chemical contamination: DNA damage and residue analysis

    SciTech Connect

    Meyers-Schoene, L. ); Shugart, L.R.; Beauchamp, J.J.; Walton, B.T. )

    1993-08-01

    Two species of turtles that occupy different ecological niches were compared for their usefulness as monitors of freshwater ecosystems where both low-level radioactive and nonradioactive contaminants are present. The pond slider (Trachemys scripta) and common snapping turtle (Chelydra serpentina) were analyzed for the presence of [sup 90]Sr, [sup 137]Cs, [sup 60]Co, and Hg, radionuclides and chemicals known to be present at the contaminated site, and single-strand breaks in liver DNA. The integrity of the DNA was examined by the alkaline unwinding assay, a technique that detects strand breaks as a biological marker of possible exposure to genotoxic agents. This measure of DNA damage was significantly increased in both species of turtles at the contaminated site compared with turtles of the same species at a reference site, and shows that contaminant-exposed populations were under more severe genotoxic stress than those at the reference site. The level of strand breaks observed at the contaminated site was high and in the range reported for other aquatic species exposed to deleterious concentrations of genotoxic agents such as chemicals and ionizing radiation. Statistically significantly higher concentrations of radionuclides and Hg were detected in the turtles from the contaminated area. Mercury concentrations were significantly higher in the more carnivorous snapping turtle compared with the slider; however, both species were effective monitors of the contaminants.

  18. Chemical exchange program analysis.

    SciTech Connect

    Waffelaert, Pascale

    2007-09-01

    As part of its EMS, Sandia performs an annual environmental aspects/impacts analysis. The purpose of this analysis is to identify the environmental aspects associated with Sandia's activities, products, and services and the potential environmental impacts associated with those aspects. Division and environmental programs established objectives and targets based on the environmental aspects associated with their operations. In 2007 the most significant aspect identified was Hazardous Materials (Use and Storage). The objective for Hazardous Materials (Use and Storage) was to improve chemical handling, storage, and on-site movement of hazardous materials. One of the targets supporting this objective was to develop an effective chemical exchange program, making a business case for it in FY07, and fully implementing a comprehensive chemical exchange program in FY08. A Chemical Exchange Program (CEP) team was formed to implement this target. The team consists of representatives from the Chemical Information System (CIS), Pollution Prevention (P2), the HWMF, Procurement and the Environmental Management System (EMS). The CEP Team performed benchmarking and conducted a life-cycle analysis of the current management of chemicals at SNL/NM and compared it to Chemical Exchange alternatives. Those alternatives are as follows: (1) Revive the 'Virtual' Chemical Exchange Program; (2) Re-implement a 'Physical' Chemical Exchange Program using a Chemical Information System; and (3) Transition to a Chemical Management Services System. The analysis and benchmarking study shows that the present management of chemicals at SNL/NM is significantly disjointed and a life-cycle or 'Cradle-to-Grave' approach to chemical management is needed. This approach must consider the purchasing and maintenance costs as well as the cost of ultimate disposal of the chemicals and materials. A chemical exchange is needed as a mechanism to re-apply chemicals on site. This will not only reduce the quantity of

  19. Investigation on the chemical constituents and variation of the flower buds of Lonicera species by UPLC-ESI-MS/MS and principle component analysis.

    PubMed

    Li, Xiao-Qin; Sun, Xiao-Hong; Cai, Shuang; Ying, Xi-Xiang; Li, Fa-Mei

    2009-08-01

    A rapid ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometric (UPLC-ESI-MS/MS) method is developed for the qualitative identification of constituents in the flower buds of seven Lonicera species. The optimal condition of separation and detection were achieved on an AcQuity UPLC BEH C18 column with a gradient elution with acetonitrile and 0.1% acetic acid within 17 min. Among the 33 constituents detected, 6 caffeoylquinic acids (including caffeic acid), 8 flavonoids and 8 iridoid glycosides were characterized based on their fragmentation patterns in collision-induced dissociation (CID) experiments and/or by comparison with standard compounds. In addition, to statistically establish the correlation and discrimination of the Lonicera species, principle component analysis (PCA) was applied in this study. Lonicera samples were divided into well-defined groups directly related to their species based on PCA in terms of the log transformed relative contents of the major caffeoylquinic acids (including caffeic acid) as the variables. All of results indicated that the method presented here is able to classify the sample species and to reveal characteristic details of the chemical constituents of different Lonicera species.

  20. Analysis of genetics and chemical contents relation compared to commonly used Cissus quadrangularis L. and barcode markers of some Thailand Cissus species.

    PubMed

    Sudmoon, Runglawan; Chaveerach, Arunrat; Tanee, Tawatchai

    2016-01-01

    Several Cissus species are commonly used as traditional and modified medicines, and their chemical constituents are major point for precise usage. However, C. quadrangularis is the only species for which the usages and the chemical composition have been reported. These data should be investigated for other species in the genus. Eight species namely C. assamica, C. carnosa, C. elongata, C. hastata, C. javana, C. pteroclada, C. quadrangular is and C. repens were evaluated for genetic relationships and chemical composition. Constructed dendrogram shows high-powered efficiency of inter-simple sequence repeat (ISSR) data used which can clearly identify different and identical species. Genetic similarity (S) value of the identical species is 0.86, whereas for different species the value can vary from 0.53 to 0.75. Four highly related species (S=0.64-0.72), C. assamica, C. carnosa, C. hastata and C. repens were selected to undergo chemical study by gas chromatography-mass spectrometry (GC-MS) on the methanol crude extract. Only one compound, β-sitosterol, found in the four species is identical to the compound reported from C. quadrangular is, where there were five identical chemicals found in the selected species. Species-specific barcode with rbcL region was constructed. Nucleotide variation was evaluated indicating genetic distance value of 0.025 to 0.072.

  1. Multivariate Quantitative Chemical Analysis

    NASA Technical Reports Server (NTRS)

    Kinchen, David G.; Capezza, Mary

    1995-01-01

    Technique of multivariate quantitative chemical analysis devised for use in determining relative proportions of two components mixed and sprayed together onto object to form thermally insulating foam. Potentially adaptable to other materials, especially in process-monitoring applications in which necessary to know and control critical properties of products via quantitative chemical analyses of products. In addition to chemical composition, also used to determine such physical properties as densities and strengths.

  2. Mid-infrared laser-spectroscopic sensing of chemical species

    PubMed Central

    Sigrist, Markus W.

    2014-01-01

    This letter reports on mid-infrared laser-based detection and analysis of chemical species. Emphasis is put on broadly tunable laser sources and sensitive detection schemes. Selected examples from our lab illustrate the performance and potential of such systems in various areas including environmental and medical sensing. PMID:26257952

  3. Chemical analysis and antioxidant activity of the essential oils of three Piperaceae species growing in the central region of Cuba.

    PubMed

    Rodríguez, Elisa Jorge; Saucedo-Hernández, Yanelis; Vander Heyden, Yvan; Simó-Alfonso, Ernesto F; Ramis-Ramos, Guillermo; Lerma-García, María Jesús; Monteagudo, Urbano; Bravo, Luis; Medinilla, Mildred; de Armas, Yuriam; Herrero-Martínez, José Manuel

    2013-09-01

    The present study describes the phytochemical profile and antioxidant activity of the essential oils of three Piperaceae species collected in the central region of Cuba. The essential oils of Piper aduncum, P. auritum and P. umbellatum leaves, obtained by hydrodistillation, were analyzed by gas chromatography-mass spectrometry. The main components of P. aduncum oil were piperitone (34%), camphor (17.1%), camphene (10.9%), 1,8-cineol (8.7%) and viridiflorol (7.4%), whereas that of P. auritum and P. umbellatum was safrole (71.8 and 26.4%, respectively). The antioxidant properties of the essential oils were also evaluated using several assays for radical scavenging ability (DPPH test and reducing power) and inhibition of lipid oxidation (ferric thiocyanate method and evaluation against Cucurbita seed oil by peroxide, thiobarbituric acid and p-anisidine methods). P. auritum showed the strongest antioxidant activity among the Piper species investigated, but lower than those of butylated hydroxyanisol and propyl gallate.

  4. Chemical process hazards analysis

    SciTech Connect

    1996-02-01

    The Office of Worker Health and Safety (EH-5) under the Assistant Secretary for the Environment, Safety and Health of the US Department (DOE) has published two handbooks for use by DOE contractors managing facilities and processes covered by the Occupational Safety and Health Administration (OSHA) Rule for Process Safety Management of Highly Hazardous Chemicals (29 CFR 1910.119), herein referred to as the PSM Rule. The PSM Rule contains an integrated set of chemical process safety management elements designed to prevent chemical releases that can lead to catastrophic fires, explosions, or toxic exposures. The purpose of the two handbooks, ``Process Safety Management for Highly Hazardous Chemicals`` and ``Chemical Process Hazards Analysis,`` is to facilitate implementation of the provisions of the PSM Rule within the DOE. The purpose of this handbook ``Chemical Process Hazards Analysis,`` is to facilitate, within the DOE, the performance of chemical process hazards analyses (PrHAs) as required under the PSM Rule. It provides basic information for the performance of PrHAs, and should not be considered a complete resource on PrHA methods. Likewise, to determine if a facility is covered by the PSM rule, the reader should refer to the handbook, ``Process Safety Management for Highly Hazardous Chemicals`` (DOE- HDBK-1101-96). Promulgation of the PSM Rule has heightened the awareness of chemical safety management issues within the DOE. This handbook is intended for use by DOE facilities and processes covered by the PSM rule to facilitate contractor implementation of the PrHA element of the PSM Rule. However, contractors whose facilities and processes not covered by the PSM Rule may also use this handbook as a basis for conducting process hazards analyses as part of their good management practices. This handbook explains the minimum requirements for PrHAs outlined in the PSM Rule. Nowhere have requirements been added beyond what is specifically required by the rule.

  5. Quantum chemical study of methane oxidation species

    NASA Technical Reports Server (NTRS)

    Jackels, Charles F.

    1993-01-01

    The research funded by this project has focused on quantum chemical investigations of molecular species thought to be important in the chemistry of the earth's upper and lower atmospheres. The body of this report contains brief discussions of the results of the several phases of this investigation. In many instances these results have been presented at scientific meetings and/or published in refereed journals. Those bibliographic references are given. In addition to the study of specific chemical systems, there were several phases during the course of this investigation where much of the effort went into the development and modification of computer codes necessary to carry out these calculations on the wide range of computer equipment used during this study. This type of code maintenance and development work did not generally result in publications and presentations, but a brief review is given.

  6. The Chemical Form of Metal Species Released from Corroded Taper Junctions of Hip Implants: Synchrotron Analysis of Patient Tissue.

    PubMed

    Di Laura, Anna; Quinn, Paul D; Panagiotopoulou, Vasiliki C; Hothi, Harry S; Henckel, Johann; Powell, Jonathan J; Berisha, Fitim; Amary, Fernanda; Mosselmans, J Fred W; Skinner, John A; Hart, Alister J

    2017-09-08

    The mechanisms of metal release from the articulation at the head cup bearing and the tapered junctions of orthopaedic hip implants are known to differ and the debris generated varies in size, shape and volume. Significantly less metal is lost from the taper junction between Cobalt-Chromium-Molybdenum (CoCrMo) and Titanium (Ti) components (fretting-corrosion dominant mechanism), when compared to the CoCrMo bearing surfaces (wear-corrosion dominant mechanism). Corrosion particles from the taper junction can lead to Adverse Reactions to Metal Debris (ARMD) similar to those seen with CoCrMo bearings. We used synchrotron methods to understand the modes underlying clinically significant tissue reactions to Co, Cr and Ti by analysing viable peri-prosthetic tissue. Cr was present as Cr2O3 in the corroded group in addition to CrPO4 found in the metal-on-metal (MoM) group. Interestingly, Ti was present as TiO2 in an amorphous rather than rutile or anatase physical form. The metal species were co-localized in the same micron-scale particles as result of corrosion processes and in one cell type, the phagocytes. This work gives new insights into the degradation products from metal devices as well as guidance for toxicological studies in humans.

  7. Theory of chemical bonds in metalloenzymes XI: Full geometry optimization and vibration analysis of porphyrin iron-oxo species

    NASA Astrophysics Data System (ADS)

    Shoji, Mitsuo; Isobe, Hiroshi; Saito, Toru; Kitagawa, Yasutaka; Yamanaka, Shusuke; Kawakami, Takashi; Okumura, Mitsutaka; Yamaguchi, Kizashi

    Physiochemical properties of compound I and II intermediate states for heme enzymes (catalase, peroxidase, P450) and inorganic models are investigated by hybrid density functional theory. Used theoretical models are composed of an oxoferryl porphyrin and an axial ligand, which are cresol, methylimidazole, methylthiol, and chloride for catalase, peroxidase, P450, and inorganic models, respectively. The oxoferryl bonds are characterized in terms of bond lengths and vibration frequencies. It is found that the oxoferryl bond lengths (the stretching frequency) are shorter (higher) than those of the X-ray crystal structures of enzymes, on the other hand for inorganic models, they are comparable with the experimental values. Spin density distributions showed that radical state at the compound I can be classified into two types: (1) porphyrin radical state and (2) axial ligand radical state. Peroxidase and inorganic model are in the former case and Catalase and P450 are in the later case at the present calculation models. Magnetic interactions between oxoferryl and ligand radical moieties are analyzed by the natural orbital analysis and it is showed that the effective exchange integral (J) values are strongly related to the radical spin density distributions: axial ligand radical tends to increase the antiferromagnetic interaction. Mössbauer shift parameters are also evaluated and it is shown that iron charge states are similar for these models.

  8. Chemical and Thermal Analysis

    NASA Technical Reports Server (NTRS)

    Bulluck, J. W.; Rushing, R. A.; Thornton, C. P.

    1996-01-01

    Work has included significant research in several areas aimed at further clarification of the aging and chemical failure mechanism of thermoplastics (PVDF or Tefzel) for pipes. Among the areas investigated were the crystallinity changes associated with both the Coflon and Tefzel after various simulated environmental exposures using X-Ray diffraction analysis. We have found that significant changes in polymer crystallinity levels occur as a function of the exposures. These crystallinity changes may have important consequences on the fracture, fatigue, tensile, and chemical resistance of the materials. We have also noted changes in the molecular weight distribution of the Coflon material using a dual detector Gel Permeation Analysis. Again these changes may result in variation in the mechanical and chemical properties in the material. We conducted numerous analytical studies with methods including X-Ray Diffraction, Gel Permeation Chromatography, Fourier Transform Infrared Spectroscopy, Thermogravimetric Analysis, and Differential Scanning Calorimetry. We investigated a number of aged samples of both Tefzel and Coflon that were forwarded from MERL. Pressurized tests were performed in a modified Fluid G, which we will call G2. In this case the ethylene diamine concentration was increased to 3 percent in methanol. Coflon pipe sections and powdered Coflon were exposed in pressure cells at 1700 psi at three separate test temperatures, 70 C, 110 C, and 130 C. The primary purpose of the pressure tests in Fluid G2 was to further elucidate the aging mechanism of PVDF degradation.

  9. One species, many terpenes: matching chemical and biological diversity.

    PubMed

    Loreto, Francesco; Bagnoli, Francesca; Fineschi, Silvia

    2009-08-01

    Volatile terpenes have been proposed as chemotaxonomic markers, despite the strong environmental control on their synthesis. To clarify whether chemical profiles match biological diversity, cork oak, a monoterpene-emitting species that has been bred by humans and frequently hybridizes with other oaks, is a useful case-study. Analysis of the available genetic information in cork oak provenances suggests that volatile terpenes might indeed suitably track geographical diversity even at the intraspecific level. Phylogeographical diversity does not reflect chemical diversity in other evergreen oaks that have not been intensively bred. Breeding for productive traits might therefore drive selection for terpene diversity, in turn modulating important adaptive mechanisms against biotic and abiotic stressors.

  10. Chemical and Thermal Analysis

    NASA Technical Reports Server (NTRS)

    Bulluck, J. W.; Rushing, R. A.

    1997-01-01

    Work during the past three years has included significant research in several areas aimed at further clarification of the aging and chemical failure mechanism of thermoplastics (PVDF or Tefzel) for pipes. Among the areas investigated were the crystallinity changes associated with both the Coflon and Tefzel after various simulated environmental exposures using X-Ray diffraction analysis. We have found that significant changes in polymer crystallinity levels occur as a function of the exposures. These crystallinity changes may have important consequences on the fracture, fatigue, tensile, and chemical resistance of the materials. We have also noted changes in the molecular weight distribution and the increased crosslinking of the Coflon material using Gel Permeation Chromatographic Analysis. Again these changes may result in variations in the mechanical and chemical properties in the material. We conducted numerous analytical studies with methods including X-ray Diffraction, Gel Permeation Chromatography, Fourier Transform Infrared Spectroscopy, and Differential Scanning Calorimetry. We investigated a plethora of aged samples of both Tefzel and Coflon that were forwarded from MERL. Pressurized tests were performed on powdered PVDF in a modified Fluid A, which we will call A-2. In this case the ethylene diamine concentration was increased to 3 percent in methanol. Coflon pipe sections and powdered Coflon were exposed in pressure cells at 1700 psi at three separate test temperatures.

  11. Chemical and Thermal Analysis

    NASA Technical Reports Server (NTRS)

    Bulluck, J. W.; Rushing, R. A.

    1994-01-01

    Thermal decomposition activation energies have been determined using two methods of Thermogravimetric Analysis (TGA), with good correlation being obtained between the two techniques. Initial heating curves indicated a two-component system for Coflon (i.e. polymer plus placticizer) but a single component system for Tefzel. Two widely differing activation energies were for Coflon supported this view, 15 kcl/mol being associated with plasticizer, and 40 kcal/mol with polymer degradation. With Tefzel, values were 40-45 kcal/mol, the former perhaps being associated with a low molecular weight fraction. Appropriate acceleration factors have been determined. Thermomechanical Analysis (TMA) has shown considerable dimensional change during temperature cycles. For unaged pipe sections heating to 100 C and then holding the temperature resulted in a stable thickness increase of 2%, whereas the Coflon thickness decreased continuously, reaching -4% in 2.7 weeks. Previously strained tensile bars of Tefzel expanded on cooling during TMA. SEM performed on H2S-aged Coflon samples showed significant changes in both physical and chemical nature. The first may have resulted from explosive decompression after part of the aging process. Chemically extensive dehydrofluorination was indicated, and sulfur was present as a result of the aging. These observations indicate that chemical attack of PVDF can occur in some circumstances.

  12. Laser-Beam-Absorption Chemical-Species Monitor

    NASA Technical Reports Server (NTRS)

    Gersh, Michael; Goldstein, Neil; Lee, Jamine; Bien, Fritz; Richtsmeier, Steven

    1996-01-01

    Apparatus measures concentration of chemical species in fluid medium (e.g., gaseous industrial process stream). Directs laser beam through medium, and measures intensity of beam after passage through medium. Relative amount of beam power absorbed in medium indicative of concentration of chemical species; laser wavelength chosen to be one at which species of interest absorbs.

  13. Chemical and Thermal Analysis

    NASA Technical Reports Server (NTRS)

    Bulluck, J. W.; Rushing, R. A.

    1995-01-01

    During the past six months we have conducted significant research in several domains in order to clarify and understanding the aging and chemical failure mechanism of thermoplastics (PVDF or Tefzel) for pipes. We organized numerous analytical studies with methods including Fourier Transform Infrared Spectroscopy, Dynamic Mechanical Analysis, Differential Scanning Calorimetry, and Stress Relaxation experiments. In addition we have reanalyzed previous thermogravimetric data concerning the rate of deplasticization of Coflon pipe. We investigated a number of aged samples of both Tefzel and Coflon that were forwarded from MERL. We conducted stress relaxation experiments of Coflon pipe at several temperatures and determined an activation energy. We also examined the dynamic mechanical response PVDF during deplasticization and during methanol plasticization. We performed numerous DSC analyses to research the changing crystalline morphology. We have noted significant changes in crystallinity upon aging for both PVDF and Tefzel. Little variation in elemental composition was noted for many of the aged Coflon and Tefzel samples tested.

  14. Chemical Sensing in Process Analysis.

    ERIC Educational Resources Information Center

    Hirschfeld, T.; And Others

    1984-01-01

    Discusses: (1) rationale for chemical sensors in process analysis; (2) existing types of process chemical sensors; (3) sensor limitations, considering lessons of chemometrics; (4) trends in process control sensors; and (5) future prospects. (JN)

  15. Atmospheric surface layer similarity theory applied to chemically reactive species

    SciTech Connect

    Arellano, J.V.G. De; Duynkerke, P.G.; Zeller, K.F. |

    1995-01-01

    The similarity theory for the atmospheric surface layer is extended to study the flux-gradient relationships of chemically reactive species. A second-order model is developed to calculate the flux-gradient relationships and the (co-)variances of momentum, temperature, and concentration. The equations of the statistical quantities of the chemical species take chemical reactions into account. The closure constants are adjusted for a near-neutral surface layer using micrometeorological measurements. All model equations are made nondimensional and without chemistry can be solved as a function of a nondimensional parameter which accounts for the atmospheric stability z/L only. In the case of an irreversible second-order chemical reaction, three new dimensionless scaling parameters are introduced by the chemical processes. Model calculations of the momentum and temperature (co-)variances are in good agreement with the observations over the whole range of the atmospheric stability. If the concentration of one chemical species (abundant) is much higher than the concentration of the other species (scarce), then one finds the largest deviations for the scarce chemical species. The magnitude of these deviations depends on the Damkoehler numbers and on the direction of the transport of the two chemical species, i.e., both deposited/emitted or one deposited and the other emitted. The abundant chemical species behaves as a passive scalar, i.e., temperature or moisture. Therefore in the case of scarce chemical species and Damkoehler numbers close to unity (moderate chemistry), one cannot use the same flux-gradient relationship for temperature and for chemically reactive species. A similar behavior is found if one takes into account a backward chemical reaction (photodissociation) to the second-order chemical reaction.

  16. Comparing ecotoxicological effect concentrations of chemicals established in multi-species vs. single-species toxicity test systems.

    PubMed

    De Laender, Frederik; De Schamphelaere, Karel A C; Vanrolleghem, Peter A; Janssen, Colin R

    2009-02-01

    Most ecological effect assessment methodologies use effect concentrations derived from single-species testing (ECx,single-species-test) as the basis to estimate 'safe' environmental concentrations (such as environmental quality criteria). Here, we examined to what extent such ECx,single-species-test are representative for population-level effect concentrations in a community setting (ECx,multi-species-test). Data from USEPA's ECOTOX database revealed the existence of considerable scatter around the relationship between ECx,single-species-test (endpoint: mortality) and ECx,multi-species-test (endpoint: population abundance). However, we demonstrate that this scatter is reduced when ECx,single-species-test and ECx,multi-species-test are determined simultaneously and by the same research group. Indeed, if these conditions are fulfilled, the quotient of both ECx values for invertebrates approaches 1 for chemicals that directly target invertebrates. Unfortunately, comparable data for other classes of chemicals and/or taxonomic groups were not found. However, theoretical ecosystem model simulations, which confirmed the results based on the above-mentioned analysis of the ECOTOX database, indicated that for phytoplankton, EC10,single-species-test>EC10,multi-species-test, for chemicals that directly target invertebrates. For chemicals that directly target phytoplankton, the ecosystem model simulations suggest that ECx,single-species-test>ECx,multi-species-test for both phytoplankton and invertebrates. Hence, our observation based on the analysis of existing experimental data that the ECx,single-species-test is similar to the ECx,multi-species-test may be biased by the fact that only data were available for invertebrates and for chemicals targeting invertebrates. Experimental research is required to test the predictions made by the model simulations for phytoplankton as well as for chemicals directly targeting phytoplankton.

  17. Structural determination of individual chemical species in a mixed system by iterative transformation factor analysis-based X-ray absorption spectroscopy combined with UV-visible absorption and quantum chemical calculation.

    PubMed

    Ikeda, Atsushi; Hennig, Christoph; Rossberg, André; Tsushima, Satoru; Scheinost, Andreas C; Bernhard, Gert

    2008-02-15

    A multitechnique approach using extended X-ray absorption fine structure (EXAFS) spectroscopy based on iterative transformation factor analysis (ITFA), UV-visible absorption spectroscopy, and density functional theory (DFT) calculations has been performed in order to investigate the speciation of uranium(VI) nitrate species in acetonitrile and to identify the complex structure of individual species in the system. UV-visible spectral titration suggests that there are four different species in the system, that is, pure solvated species, mono-, di-, and trinitrate species. The pure EXAFS spectra of these individual species are extracted by ITFA from the measured spectral mixtures on the basis of the speciation distribution profile calculated from the UV-visible data. Data analysis of the extracted EXAFS spectra, with the help of DFT calculations, reveals the most probable complex structures of the individual species. The pure solvated species corresponds to a uranyl hydrate complex with an equatorial coordination number (CNeq) of 5, [UO2(H2O)5]2+. Nitrate ions tend to coordinate to the uranyl(VI) ion in a bidentate fashion rather than a unidentate one in acetonitrile for all the nitrate species. The mononitrate species forms the complex of [UO2(H2O)3NO3]+ with a CNeq value of 5, while the di- and trinitrate species have a CNeq value of 6, corresponding to [UO2(H2O)2(NO3)2]0 (D2h) and [UO2(NO3)3]- (D3h), respectively.

  18. Cross-species conservation of endocrine pathways: a critical analysis of tier 1 fish and rat screening assays with 12 model chemicals.

    PubMed

    Ankley, Gerald T; Gray, L Earl

    2013-04-01

    Many structural and functional aspects of the vertebrate hypothalamic-pituitary-gonadal (HPG) axis are known to be highly conserved, but the significance of this from a toxicological perspective has received comparatively little attention. High-quality data generated through development and validation of Tier 1 tests for the U.S. Environmenal Protection Agency Endocrine Disruptor Screening Program (EDSP) offer a unique opportunity to compare responses of mammals versus fish to chemicals that may affect shared pathways within the HPG axis. The present study focuses on data generated with model chemicals that act (primarily) as estrogen receptor agonists (17α-ethynylestradiol, methoxychlor, bisphenol A), androgen receptor agonists (methyltestosterone, 17β-trenbolone), androgen receptor antagonists (flutamide, vincolozolin, p,p'-DDE), or inhibitors of different steroidogenic enzymes (ketoconazole, fadrozole, fenarimol, prochloraz). All 12 chemicals had been tested in the EDSP fish short-term (21 d) reproduction assay and in one or more of the four in vivo Tier 1 screens with rats (uterotrophic, Hershberger, male and female pubertal assays). There was a high concordance between the fish and rat assays with respect to identifying chemicals that impacted specific endocrine pathways of concern. Although most chemicals were detected as positive in both rat and fish assays, eliminating data from one class of vertebrate or the other would weaken the battery. For example, the effects of competitive inhibitors of steroid hormone synthesis were far more obvious in the fish assay, whereas the activity of androgen receptor antagonists was clearer in mammalian assays. The observations are significant both to the cross-species extrapolation of toxicity of HPG-active substances and the optimization of screening and testing frameworks for endocrine-disrupting chemicals. Copyright © 2013 SETAC.

  19. Model reduction for stochastic chemical systems with abundant species.

    PubMed

    Smith, Stephen; Cianci, Claudia; Grima, Ramon

    2015-12-07

    Biochemical processes typically involve many chemical species, some in abundance and some in low molecule numbers. We first identify the rate constant limits under which the concentrations of a given set of species will tend to infinity (the abundant species) while the concentrations of all other species remains constant (the non-abundant species). Subsequently, we prove that, in this limit, the fluctuations in the molecule numbers of non-abundant species are accurately described by a hybrid stochastic description consisting of a chemical master equation coupled to deterministic rate equations. This is a reduced description when compared to the conventional chemical master equation which describes the fluctuations in both abundant and non-abundant species. We show that the reduced master equation can be solved exactly for a number of biochemical networks involving gene expression and enzyme catalysis, whose conventional chemical master equation description is analytically impenetrable. We use the linear noise approximation to obtain approximate expressions for the difference between the variance of fluctuations in the non-abundant species as predicted by the hybrid approach and by the conventional chemical master equation. Furthermore, we show that surprisingly, irrespective of any separation in the mean molecule numbers of various species, the conventional and hybrid master equations exactly agree for a class of chemical systems.

  20. Model reduction for stochastic chemical systems with abundant species

    SciTech Connect

    Smith, Stephen; Cianci, Claudia; Grima, Ramon

    2015-12-07

    Biochemical processes typically involve many chemical species, some in abundance and some in low molecule numbers. We first identify the rate constant limits under which the concentrations of a given set of species will tend to infinity (the abundant species) while the concentrations of all other species remains constant (the non-abundant species). Subsequently, we prove that, in this limit, the fluctuations in the molecule numbers of non-abundant species are accurately described by a hybrid stochastic description consisting of a chemical master equation coupled to deterministic rate equations. This is a reduced description when compared to the conventional chemical master equation which describes the fluctuations in both abundant and non-abundant species. We show that the reduced master equation can be solved exactly for a number of biochemical networks involving gene expression and enzyme catalysis, whose conventional chemical master equation description is analytically impenetrable. We use the linear noise approximation to obtain approximate expressions for the difference between the variance of fluctuations in the non-abundant species as predicted by the hybrid approach and by the conventional chemical master equation. Furthermore, we show that surprisingly, irrespective of any separation in the mean molecule numbers of various species, the conventional and hybrid master equations exactly agree for a class of chemical systems.

  1. [Comparative study on chemical quality of main species of epimedium].

    PubMed

    Han, Sun; Xie, Yuan-Yuan; Wang, Yi-Ming; Liang, Qiong-Lin; Luo, Guo-An

    2012-04-01

    This study was to comprehensively evaluate the chemical quality of main species of epimedium planted in China. The contents of 5 marker compounds, epimedin A, epimedin B, epimedin C, icariin and baohuoside I, as well as total flavonoids of 22 samples of 8 officinal species of Epimedium were determined by HPLC and UV, separately. Some physical and chemical tests (H2O, total ash, acid-insoluble ash and EtOH extract) were also carried out to investigate their chemical qualities. There were significant differences in types and contents of prenyl-flavonoid glycosides such as epimedin A, epimedin B, epimedin C, icariin and baohuoside I in different species, meanwhile, the physical and chemical parameters results also showed that there were obvious differences in chemical quality among different species of epimedium herb. The results provide theoretical and experimental basis for the establishment of comprehensive quality assessment system of epimedium in China.

  2. Chemical analysis of aquatic pheromones in fish.

    PubMed

    Stewart, Michael; Baker, Cindy F; Sorensen, Peter W

    2013-01-01

    Pheromones are chemicals that pass between members of the same species that have inherent meaning. In the case of fish, pheromones are water-soluble and found in low concentrations. As such, sensitive and selective methods are needed to separate and analyze these pheromones from an environmental matrix that may contain many other chemicals. This chapter describes a generic method used to concentrate and identify these chemicals and two extremely sensitive and selective methods for analysis, namely, mass spectrometry and enzyme-linked immunosorbent assay.

  3. Chemical composition of various Ephedra species

    PubMed Central

    Ibragic, Saida; Sofić, Emin

    2015-01-01

    The medicinal significance of Ephedra is based on the sympathomimetic properties of ephedrine (E) alkaloids. Pharmacological effects depend on the phytocomposition of individual Ephedra species. The aim of this study was to measure the total alkaloids content (TAC), total phenolics content (TPC), and total flavonoids content (TFC) and determine their relationship in dry herb of Ephedra major, Ephedra distachya subsp. helvetica, Ephedra monosperma, Ephedra fragilis, Ephedra foeminea, Ephedra alata, Ephedra altissima and Ephedra foliata. Nowadays, medicinal use of Ephedrae herba is limited, but the abuse of its psychostimulants is rising. In this study, TAC, TPC and TFC were determined using spectrophotometric methods. For the first time, ultra-performance liquid chromatography with ultraviolet detection (UPLC-UV) was used for separation and quantification of E-type alkaloids of various Ephedra species. The highest TPC and TFC were found in E. alata (53.3 ± 0.1 mg Gallic acid equivalents/g dry weight, 2.8 mg quercetin equivalents/g dry weight, respectively). The total content of E and pseudoephedrine determined by UPLC-UV varied between 20.8 mg/g dry weight (E. distachya subsp. helvetica) and 34.7 mg/g dry weight (E. monosperma). The variable content and ratio between secondary metabolites determined in different Ephedra species reflects their metabolic activities. Utilization of UPLC-UV unveiled that this technique is sensitive, selective, and useful for separation and quantification of different alkaloids in complex biological matrixes. The limit of detection was 5 ng. Application of UPLC-UV can be recommended in quick analyses of E-type alkaloids in forensic medicine and quality control of pharmaceutical preparations. PMID:26295290

  4. Chemical changes with maturation of the bamboo species phyllostachys pubescens

    Treesearch

    X.B. Li; T.F. Shupe; G.F. Peter; C.Y. Hse; T.L. Eberhardt

    2007-01-01

    Chemical changes with maturation of the bamboo species Phyllostachys pubescens. Bamboo chemical properties were measured at three different heights from one-, three- and five-year-old plants and at three different radial positions from the thre-year-old culms of Phyllostachys pubescenssouth-eastern USA. Small but significant...

  5. Chemical substructure analysis in toxicology

    SciTech Connect

    Beauchamp, R.O. Jr.

    1990-12-31

    A preliminary examination of chemical-substructure analysis (CSA) demonstrates the effective use of the Chemical Abstracts compound connectivity file in conjunction with the bibliographic file for relating chemical structures to biological activity. The importance of considering the role of metabolic intermediates under a variety of conditions is illustrated, suggesting structures that should be examined that may exhibit potential activity. This CSA technique, which utilizes existing large files accessible with online personal computers, is recommended for use as another tool in examining chemicals in drugs. 2 refs., 4 figs.

  6. A Comparative Analysis of the Chemical Composition, Anti-Inflammatory, and Antinociceptive Effects of the Essential Oils from Three Species of Mentha Cultivated in Romania.

    PubMed

    Mogosan, Cristina; Vostinaru, Oliviu; Oprean, Radu; Heghes, Codruta; Filip, Lorena; Balica, Georgeta; Moldovan, Radu Ioan

    2017-02-10

    This work was aimed at correlating the chemotype of three Mentha species cultivated in Romania with an in vivo study of the anti-inflammatory and antinociceptive effects of essential oils. The selected species were Mentha piperita L. var. pallescens (white peppermint), Mentha spicata L. subsp. crispata (spearmint), and Mentha suaveolens Ehrh. (pineapple mint). Qualitative and quantitative analysis of the essential oils isolated from the selected Mentha species was performed by gas chromatography coupled with mass spectrometry (GC-MS). The anti-inflammatory activity of the essential oils was determined by the rat paw edema test induced by λ-carrageenan. The antinociceptive effect of the essential oils was evaluated by the writhing test in mice, using 1% (v/v) acetic acid solution administered intraperitonealy and by the hot plate test in mice. The results showed a menthol chemotype for M. piperita pallescens, a carvone chemotype for M. spicata, and a piperitenone oxide chemotype for M. suaveolens. The essential oil from M. spicata L. (EOMSP) produced statistically significant and dose-dependent anti-inflammatory and antinociceptive effects.

  7. Chemical kinetics of Cs species in an alkali-activated municipal solid waste incineration fly ash and pyrophyllite-based system using Cs K-edge in situ X-ray absorption fine structure analysis

    NASA Astrophysics Data System (ADS)

    Shiota, Kenji; Nakamura, Takafumi; Takaoka, Masaki; Nitta, Kiyofumi; Oshita, Kazuyuki; Fujimori, Takashi; Ina, Toshiaki

    2017-05-01

    We conducted in situ X-ray absorption fine structure (in situ XAFS) analysis at the Cs K-edge to investigate the chemical kinetics of Cs species during reaction in an alkali-activated municipal solid waste incineration fly ash (MSWIFA) and pyrophyllite-based system. Understanding the kinetics of Cs is essential to the design of appropriate conditions for Cs stabilization. In situ XAFS analysis of four pastes, prepared from NaOHaq, sodium silicate solution, pyrophyllite, and MSWIFA with the addition of CsCl, was conducted in custom-built reaction cells at four curing temperatures (room temperature, 60 °C, 80 °C, 105 °C) for approximately 34 h. The results indicated that the change in Cs species during reaction at room temperature was small, while changes at higher temperatures were faster and more extreme, with the fastest conversion to pollucite occurring at 105 °C. Further analysis using a leaching test and a simple reaction model for Cs species during reaction showed that the pollucite formation rate was dependent on the curing temperature and had a significant negative correlation with Cs leaching. The activation energy of pollucite formation was estimated to be 31.5 kJ/mol. These results revealed that an important change in the chemical state of Cs occurs during reaction in the system.

  8. Sources of Chemical Species in Enceladus’ Plumes

    NASA Astrophysics Data System (ADS)

    Matson, Dennis L.; Johnson, T. V.; Lunine, J. I.; Castillo-Rogez, J. C.

    2009-09-01

    The combined observations of Saturn's moon Enceladus by the Cassini CAPS, INMS and UVIS instruments detected water vapor geysers in which were present molecular nitrogen (N2), carbon dioxide (CO2), ammonia (NH3), methane (CH4), propane (C3H8), acetylene (C2H2), H2CO, C2H6, C3H6, and other species, together with the decomposition products of water (see Waite et al., 2006, Science 311, 1419; Waite et al., 2009, EOS Trans. AGU 90(22) P32A-02). In addition the CDA instrument reports various salts of sodium (Postberg et al, Nature 459, 1098). We proposed that the presence of N2 in the plume indicates thermal decomposition of ammonia, and hence high temperatures in the interior of the moon (e.g., 500 to 800 K)(Matson et al., 2007, Icarus 187, 569). (The predicted presence of ammonia has now been confirmed by the recent observations.) Other possibilities include the earlier processing of materials in planetesimals before their incorporation in Enceladus. Such a hot environment is also suitable for the production of methane (CH4) from carbon monoxide (CO), or carbon dioxide (CO2). The presence of C2H2 and C3H8 strongly suggests that catalytic reactions took place within a hot environment. The internal environment of Enceladus is inferred to be or have been favorable for aqueous, catalytic chemistry that permits the synthesis of many complex organic compounds. This work has been conducted at the Jet Propulsion Laboratory, California Institute of Technology under a contract with the National Aeronautics and Space Administration. Copyright 2009 California Institute of Technology. Government sponsorship acknowledged.

  9. Diffusion of inorganic chemical species in compacted clay soil

    NASA Astrophysics Data System (ADS)

    Shackelford, Charles D.; Daniel, David E.; Liljestrand, Howard M.

    1989-08-01

    This research was conducted to study the diffusion of inorganic chemicals in compacted clay soil for the design of waste containment barriers. The effective diffusion coefficients ( D ∗) of anionic (Cl -, Br -, and I -) and cationic (K +, Cd 2+, and Zn 2+) species in a synthetic leachate were measured. Two clay soils were used in the study. The soils were compacted and pre-soaked to minimize mass transport due to suction in the soil. The results of the diffusion tests were analyzed using two analytical solutions to Fick's second law and a commercially available semi-analytical solution, POLLUTE 3.3. Mass balance calculations were performed to indicate possible sinks/sources in the diffusion system. Errors in mass balance were attributed to problems with the chemical analysis (I -), the inefficiency of the extraction procedure (K +), precipitation (Cd 2+ and Zn 2+), and chemical complexation (Cl - and Br -). The D ∗ values for Cl - reported in this study are in excellent agreement with previous findings for other types of soil. The D ∗ values for the metals (K +, Cd 2+, and Zn 2+) are thought to be high (conservative) due to: (1) Ca 2+ saturation of the exchange complex of the clays; (2) precipitation of Cd 2+ and Zn 2+; and (3) nonlinear adsorption behavior. In general, high D ∗ values and conservative designs of waste containment barriers will result if the procedures described in this study are used to determine D ∗ and the adsorption behavior of the solutes is similar to that described in this study.

  10. Pervaporation in chemical analysis.

    PubMed

    Sae-Khow, Ornthida; Mitra, Somenath

    2010-04-16

    Unlike thermal processes such as distillation, pervaporation relies on the relative rates of solute permeation through a membrane and is a combination of evaporation and gas diffusion. The analytical pervaporation systems consist of a membrane module suitable for liquid sample introduction and a vacuum (or a sweeping gas) on the permeate side. It has been used in a wide range of applications including the analysis of various organic and inorganic compounds, and sample concentration. It has been directly interfaced with gas chromatography, spectrophotometry, capillary electrophoresis, electrochemical detectors, liquid chromatography, and mass spectrometry. A wide range of liquids, slurries, and solids samples has been analyzed using these techniques. This review highlights the basic principles of the pervaporation and the state of its current development as applied to analytical chemistry.

  11. Chemical Fingerprint Analysis and Quantitative Determination of Steroidal Compounds from Dioscorea villosa, Dioscorea Species, and Dietary Supplements using UHPLC-ELSD

    PubMed Central

    Avula, Bharathi; Wang, Yan-Hong; Ali, Zulfiqar; Smillie, Troy J.

    2014-01-01

    Ultra high-performance liquid chromatography (UHPLC) with evaporative light scattering (ELS) detection was used for the quantification of steroidal saponins and diosgenin from the rhizomes or tubers of various Dioscorea species and dietary supplements that were purported to contain Dioscorea. The analysis was performed on an Acquity UPLC™ system with an UPLC™ BEH Shield RP18 column using a gradient elution with water and acetonitrile. Due to their low UV absorption, the steroidal saponins were observed by evaporative light scattering detection. The twelve compounds could be separated within 15 minutes using the developed UHPLC method with detection limits of 5–12 μg/mL with 2μL injection volume. The analytical method was validated for linearity, repeatability, accuracy, limits of detection (LOD) and limits of quantification (LOQ). The Relative Standard Deviations (RSD) for intra- and inter-day experiments were less than 3.1 %, and the recovery efficiency was 97–101 %. The total content of standard compounds was found to be in the range from 0.01–14.5% and 0.9–28.6 mg daily intake for dry plant materials and solid commercial preparations, respectively. UHPLC-mass spectrometry with a quadrupole mass analyzer and ESI source was used only for confirmation of the identity of the various saponins. The developed method is simple, rapid and especially suitable for quality control analysis of commercial products. PMID:24019066

  12. Chemical fingerprint analysis and quantitative determination of steroidal compounds from Dioscorea villosa, Dioscorea species and dietary supplements using UHPLC-ELSD.

    PubMed

    Avula, Bharathi; Wang, Yan-Hong; Ali, Zulfiqar; Smillie, Troy J; Khan, Ikhlas A

    2014-02-01

    Ultra high-performance liquid chromatography (UHPLC) with evaporative light scattering detection was used for the quantification of steroidal saponins and diosgenin from the rhizomes or tubers of various Dioscorea species and dietary supplements that were purported to contain Dioscorea. The analysis was performed on an Acquity UPLC™ system with an UPLC™ BEH Shield RP18 column using a gradient elution with water and acetonitrile. Owing to their low UV absorption, the steroidal saponins were observed by evaporative light scattering detection. The 12 compounds could be separated within 15 min using the developed UHPLC method with detection limits of 5-12 µg/mL with 2 μL injection volume. The analytical method was validated for linearity, repeatability, accuracy, limits of detection and limits of quantification. The relative standard deviations for intra- and inter-day experiments were <3.1%, and the recovery efficiency was 97-101%. The total content of standard compounds was found to be in the ranges 0.01-14.5% and 0.9-28.6 mg daily intake for dry plant materials and solid commercial preparations, respectively. UHPLC-mass spectrometry with a quadrupole mass analyzer and ESI source was used only for confirmation of the identity of the various saponins. The developed method is simple, rapid and especially suitable for quality control analysis of commercial products.

  13. Genetic verification and chemical contents identification of Allamanda species (Apocynaceae).

    PubMed

    Chaveerach, Arunrat; Aungkapattamagul, Sarocha; Tanee, Tawatchai; Noikotr, Kowit; Sudmoon, Runglawan

    2014-05-01

    Allamanda species (Apocynaceae) are popular ornamentals. Additionally, A. cathartica possesses medicinal properties whereas all other species have not been reported. This research aims to analyze genetics and chemical contents of Allamanda species existing in Thailand. The explored species are A. blanchetii, A. cathartica, A. neriifolia, A. schottii, and A. violacea. The dendrogram constructed from 16 inter-simple sequence repeat markers clearly distinguished species with genetic similarity values of 0.92-0.93 for species level and 0.50-0.76 for genus level. Diverse chemicals content in hexane extracts from A. blanchetii, A. neriifolia, A. schottii, and A. violacea were detected by gas chromatography-mass spectrometry. A high amount of squalene was found in A. blanchetii (55.81%) and A. violacea (51.09%). This content may function as a chemo preventative substance to protect people from cancer. α-Tocopherol, a form of vitamin E, was one of the predominant components found in A. violacea (26.325%), A. schottii (15.41%), and A. neriifolia (9.16%). One more substance, 9,12,15-octadecatrien-1-ol, was found to be relatively high in A. schottii (17.31%) and A. neriifolia (15.51%). Other minor and unknown compounds were also detected. The discovery of these chemicals provides an alternative and supplement for improving human well-being and pharmaceutical industries with natural resources, especially in light of the population increase.

  14. Expanding the Species and Chemical Diversity of Penicillium Section Cinnamopurpurea

    PubMed Central

    Peterson, Stephen W.; Jurjević, Željko; Frisvad, Jens C.

    2015-01-01

    A set of isolates very similar to or potentially conspecific with an unidentified Penicillium isolate NRRL 735, was assembled using a BLAST search of ITS similarity among described (GenBank) and undescribed Penicillium isolates in our laboratories. DNA was amplified from six loci of the assembled isolates and sequenced. Two species in section Cinnamopurpurea are self-compatible sexual species, but the asexual species had polymorphic loci suggestive of sexual reproduction and variation in conidium size suggestive of ploidy level differences typical of heterothallism. Accordingly we use genealogical concordance analysis, a technique valid only in heterothallic organisms, for putatively asexual species. Seven new species were revealed in the analysis and are described here. Extrolite analysis showed that two of the new species, P. colei and P. monsserratidens produce the mycotoxin citreoviridin that has demonstrated pharmacological activity against human lung tumors. These isolates could provide leads in pharmaceutical research. PMID:25853891

  15. Quantification of chemically reducing species in the phosphate ion catalyzed degradation of reducing sugars.

    PubMed

    Rizzi, George P; Amba, Eme E; Heineman, William R

    2010-09-08

    Chemically reducing species formed during phosphate ion catalyzed degradation of reducing sugars were directly quantified by titration with 2,6-dichloroindophenol (Tillman's reagent) and by measurement of open circuit electrical redox potentials. Both techniques demonstrated a time-dependent increased production of chemically reducing species in 0.1 M phosphate buffer at 100 degrees C and the increasingly negative redox potentials observed were consistent with the formation of reductones. Cyclic voltammetry (CV) was investigated in an attempt to generate and observe the sugar-derived highly reactive reducing species in situ. CV analysis of a model Amadori compound, N-(1-deoxyfructos-1-yl)piperidine, indicated oxidative waves consistent with reductone formation, but chemical instability of the oxidation products formed precluded the electrochemical detection of highly electrophilic reducing species such as reductones.

  16. Chemical fingerprint analysis and quantitative determination of pregnanes from aerial parts of caralluma species using HPLC-UV and identification by LC-ESI-TOF

    USDA-ARS?s Scientific Manuscript database

    A HPLC method is developed for the quantitative determination of five pregnane derivatives from aerial parts of Caralluma species and dietary supplements. The method is validated for linearity, repeatability, limits of detection (LOD) and limits of quantification (LOQ). The limits of detection and l...

  17. Multiple species reactive chemical transport in groundwater: A verification exercise

    SciTech Connect

    Narasimhan, T.N.; Apps, J.A.; Zhu, Ming

    1991-04-01

    Two multiple-species reactive chemical transport models (FASTCHEM and DYNAMIX) were tested against each other to check for consistency of solutions. For the particular problem studied, FASTCHEM and DYNAMIX led to differences in aqueous concentrations and mineral assemblages primarily because FASTCHEM ignores redox reactions in the transport phase of the calculations. Also, the spatial concentration profiles generated by FASTCHEM tend to be sharper than those generated by DYNAMIX because FASTCHEM is particularly designed to handle advection-dominated transport systems.

  18. Chemical thermodynamics of iodine species in the HTGR fuel particle

    SciTech Connect

    Lindemer, T.B.

    1982-09-01

    The iodine-containing species in an intact fuel particle in the high-temperature gas-cooled reactor (HTGR) have been calculated. Assumptions include: (1) attainment of chemical thermodynamic equilibrium among all species in the open porosity of the particle, primarily in the buffer layer; and (2) fission-product concentrations in proportion to their yields. The primary gaseous species is calculated to be cesium iodide; in carbide-containing fuels, gaseous barium iodide may exhibit equivalent pressures. The condensed iodine-containing phase is usually cesium iodide, but in carbide-containing fuels, barium iodide may be stable instead. Absorption of elemental iodine on the carbon in the particle appears to be less than or equal to 10/sup -4/ ..mu..g I/g C. The fission-product-spectra excess of cesium over iodine would generally be adsorbed on the carbon, but may form Cs/sub 2/MoO/sub 4/ under some circumstances.

  19. Stochastic flux analysis of chemical reaction networks.

    PubMed

    Kahramanoğulları, Ozan; Lynch, James F

    2013-12-07

    Chemical reaction networks provide an abstraction scheme for a broad range of models in biology and ecology. The two common means for simulating these networks are the deterministic and the stochastic approaches. The traditional deterministic approach, based on differential equations, enjoys a rich set of analysis techniques, including a treatment of reaction fluxes. However, the discrete stochastic simulations, which provide advantages in some cases, lack a quantitative treatment of network fluxes. We describe a method for flux analysis of chemical reaction networks, where flux is given by the flow of species between reactions in stochastic simulations of the network. Extending discrete event simulation algorithms, our method constructs several data structures, and thereby reveals a variety of statistics about resource creation and consumption during the simulation. We use these structures to quantify the causal interdependence and relative importance of the reactions at arbitrary time intervals with respect to the network fluxes. This allows us to construct reduced networks that have the same flux-behavior, and compare these networks, also with respect to their time series. We demonstrate our approach on an extended example based on a published ODE model of the same network, that is, Rho GTP-binding proteins, and on other models from biology and ecology. We provide a fully stochastic treatment of flux analysis. As in deterministic analysis, our method delivers the network behavior in terms of species transformations. Moreover, our stochastic analysis can be applied, not only at steady state, but at arbitrary time intervals, and used to identify the flow of specific species between specific reactions. Our cases study of Rho GTP-binding proteins reveals the role played by the cyclic reverse fluxes in tuning the behavior of this network.

  20. Stochastic flux analysis of chemical reaction networks

    PubMed Central

    2013-01-01

    Background Chemical reaction networks provide an abstraction scheme for a broad range of models in biology and ecology. The two common means for simulating these networks are the deterministic and the stochastic approaches. The traditional deterministic approach, based on differential equations, enjoys a rich set of analysis techniques, including a treatment of reaction fluxes. However, the discrete stochastic simulations, which provide advantages in some cases, lack a quantitative treatment of network fluxes. Results We describe a method for flux analysis of chemical reaction networks, where flux is given by the flow of species between reactions in stochastic simulations of the network. Extending discrete event simulation algorithms, our method constructs several data structures, and thereby reveals a variety of statistics about resource creation and consumption during the simulation. We use these structures to quantify the causal interdependence and relative importance of the reactions at arbitrary time intervals with respect to the network fluxes. This allows us to construct reduced networks that have the same flux-behavior, and compare these networks, also with respect to their time series. We demonstrate our approach on an extended example based on a published ODE model of the same network, that is, Rho GTP-binding proteins, and on other models from biology and ecology. Conclusions We provide a fully stochastic treatment of flux analysis. As in deterministic analysis, our method delivers the network behavior in terms of species transformations. Moreover, our stochastic analysis can be applied, not only at steady state, but at arbitrary time intervals, and used to identify the flow of specific species between specific reactions. Our cases study of Rho GTP-binding proteins reveals the role played by the cyclic reverse fluxes in tuning the behavior of this network. PMID:24314153

  1. Detection and quantitative analysis of chemical species in Hanford tank materials using Raman spectroscopy technology: FY94, January 1, 1994--March 31, 1995

    SciTech Connect

    Vickers, T.J.; Mann, C.

    1995-09-12

    This report provides a summary of work completed in FY-94 by FSU to develop and investigate the feasibility of using Raman spectroscopy with Hanford tank waste materials. Raman performance impacts from sample morphology, including the effects of absorption, particle size, density, color and refractive index, are discussed. An algorithm for relative species concentration measurement from Raman data is presented. An Algorithm for applying Raman to tank waste core screening is presented and discussed. A library of absorption and Raman spectra are presented that support this work.

  2. Detection and Quantitative Analysis of Chemical Species in Hanford Tank Materials Using Raman Spectroscopy Technology: FY94Florida State University Raman Spectroscopy Report

    SciTech Connect

    Reich, F.R.

    1997-08-11

    This report provides a summary of work completed in FY-94 by FSU to develop and investigate the feasibility of using Raman spectroscopy with Hanford tank waste materials. Raman performance impacts from sample morphology, including the effects of absorption, particle size, density, color and refractive index, are discussed. An algorithm for relative species concentration measurement from Raman data is presented. An Algorithm for applying Raman to tank waste core screening is presented and discussed. A library of absorption and Raman spectra are presented that support this work.

  3. Taxonomic, genetic, chemical and estrogenic characteristics of Epimedium species.

    PubMed

    Shen, P; Guo, B L; Gong, Y; Hong, Deborah Y Q; Hong, Y; Yong, E L

    2007-05-01

    To understand the factors contributing to estrogenic properties of extracts from the genus Epimedium L. (Berberidaceae), we performed taxonomic, genetic and chemical characterization on 37 specimens from 18 species and related these to estrogen receptor (ERalpha and ERbeta) bioactivity, as measured by reporter genes in stable human cells. Boot strap values derived from amplified fragment length polymorphisms indicated that specimens of E. koreanum, E. brevicornum, E. myrianthum, E. leishanense, and E. membranaceum were genetically distinct and this was supported by their very similar ERalpha activities. In contrast, specimens from E. pubescens and E. sagittatum were diverse both genetically, chemically and in terms of ERalpha and ERbeta bioactivities. Strikingly, a genetic cluster comprising six rare Epimedium species exhibited strongest ERalpha and ERbeta activity, and this bioactivity was positively correlated with content of trace flavonoid aglycones (kaempferol, apigenin, quercetin, luteolin and breviflavone B). In contrast, there was no association between estrogenic activity and the major flavonol glycoside constituents (icariin and epimedin A-C). Although they exhibited equally strong ERalpha and ERbeta activity, E. koreanum can be clearly differentiated from E. pubescens and E. brevicornum by genetic distance and its significantly lower content of epimedin C. Our morphologic, genetic, chemical and bioactivity profiling provide the basis for the production of extracts with reproducible estrogenic properties. Such reproducibility will be critical for the standardization of Epimedium-based products.

  4. Sensitivity study of SMILES-2 for chemical species

    NASA Astrophysics Data System (ADS)

    Suzuki, Makoto; Manago, Naohiro; Ozeki, Hiroyuki; Ochiai, Satoshi; Baron, Philippe

    2015-10-01

    Sensitivity studies of temperature and chemical species (Observed by ISS/JEM/SMILES: O3, HCl, ClO, HO2, BrO, HNO3, CH3CN, and Not observed by SMILES: Temperature, H2O, N2O, NO2, NO, CH3Cl, CO, H2CO, OH and O-atom) was carried out for the SMILES-2 proposal, a sub-mm and THz observation of limb emission from space over the spectral region from 400 GHz to 2.5 THz. Tentative but optimal candidate of frequency bands to cover these species was selected with 3 SIS (Superconductor-Insulator-Superconductor) mixers; SIS-1 (485-489 GHz + 523-527 GHz), SIS-2 (623-627 GHz + 648-652 GHz), SIS-3 (557 GHz + 576.3 GHz) and 2 HEB (Hot Electron Bolometer); HEB-1 (1.8 THz OH) and HEB-2 (2.06 THz O-atom). Temperature can be retrieved with 1 K precision and 1 km vertical resolution from 15 to 120 km. Other chemical species also showed very high single scan precision (random error) comparable to statistical standard error of previous satellite measurements.

  5. Astrochem: Abundances of chemical species in the interstellar medium

    NASA Astrophysics Data System (ADS)

    Maret, Sébastien; Bergin, Edwin A.

    2015-07-01

    Astrochem computes the abundances of chemical species in the interstellar medium, as function of time. It studies the chemistry in a variety of astronomical objects, including diffuse clouds, dense clouds, photodissociation regions, prestellar cores, protostars, and protostellar disks. Astrochem reads a network of chemical reactions from a text file, builds up a system of kinetic rates equations, and solves it using a state-of-the-art stiff ordinary differential equation (ODE) solver. The Jacobian matrix of the system is computed implicitly, so the resolution of the system is extremely fast: large networks containing several thousands of reactions are usually solved in a few seconds. A variety of gas phase process are considered, as well as simple gas-grain interactions, such as the freeze-out and the desorption via several mechanisms (thermal desorption, cosmic-ray desorption and photo-desorption). The computed abundances are written in a HDF5 file, and can be plotted in different ways with the tools provided with Astrochem. Chemical reactions and their rates are written in a format which is meant to be easy to read and to edit. A tool to convert the chemical networks from the OSU and KIDA databases into this format is also provided. Astrochem is written in C, and its source code is distributed under the terms of the GNU General Public License (GPL).

  6. Bayesian approach to the design of chemical species tomography experiments.

    PubMed

    Grauer, Samuel J; Hadwin, Paul J; Daun, Kyle J

    2016-07-20

    Reconstruction accuracy in chemical species tomography depends strongly on the arrangement of optical paths transecting the imaging domain. Optimizing the path arrangement requires a scheme that can predict the quality of a proposed arrangement prior to measurement. This paper presents a new Bayesian method for scoring path arrangements based on the estimated a posteriori covariance matrix. This technique focuses on defining an objective function that incorporates the same a priori information about the flow needed to carry out limited data tomography. Constrained and unconstrained path optimization studies verify the predictive capabilities of the objective function, and that superior reconstruction quality is obtained with optimized path arrangements.

  7. Chemical composition of seed oils in native Taiwanese Camellia species.

    PubMed

    Su, Mong Huai; Shih, Ming Chih; Lin, Kuan-Hung

    2014-08-01

    The aim of this study was to examine the fatty acid (FA) composition and levels in seeds of twelve native Camellia species collected in different populations of major producing regions in Taiwan. The constituents of FAs varied within and among populations. Oleic acid (OA) was found to be the predominant FA constituent in all species. Remarkably high levels of unsaturated OA and linoleic acid (LA), found in two populations of Camellia tenuiflora (CT), C. transarisanensis (CTA), and C. furfuracea (CFA), were similar to those reported for olive oil. The levels of saturated palmitic acid (PA) from most of the tested seed oils were less than 13%. Among the different fats, some FAs can be used as functional ingredients for topical applications. The seed oils of CT, CTA, and CFA possess chemical compounds that make them useful in health-oriented cooking due to their high OA and LA contents and low PA content.

  8. Identification and Quantitative Measurements of Chemical Species by Mass Spectrometry

    NASA Technical Reports Server (NTRS)

    Zondlo, Mark A.; Bomse, David S.

    2005-01-01

    The development of a miniature gas chromatograph/mass spectrometer system for the measurement of chemical species of interest to combustion is described. The completed system is a fully-contained, automated instrument consisting of a sampling inlet, a small-scale gas chromatograph, a miniature, quadrupole mass spectrometer, vacuum pumps, and software. A pair of computer-driven valves controls the gas sampling and introduction to the chromatographic column. The column has a stainless steel exterior and a silica interior, and contains an adsorbent of that is used to separate organic species. The detection system is based on a quadrupole mass spectrometer consisting of a micropole array, electrometer, and a computer interface. The vacuum system has two miniature pumps to maintain the low pressure needed for the mass spectrometer. A laptop computer uses custom software to control the entire system and collect the data. In a laboratory demonstration, the system separated calibration mixtures containing 1000 ppm of alkanes and alkenes.

  9. Diffusion of multi-isotopic chemical species in molten silicates

    NASA Astrophysics Data System (ADS)

    Watkins, James M.; Liang, Yan; Richter, Frank; Ryerson, Frederick J.; DePaolo, Donald J.

    2014-08-01

    Diffusion experiments in a simplified Na2O-CaO-SiO2 liquid system are used to develop a general formulation for the fractionation of Ca isotopes during liquid-phase diffusion. Although chemical diffusion is a well-studied process, the mathematical description of the effects of diffusion on the separate isotopes of a chemical element is surprisingly underdeveloped and uncertain. Kinetic theory predicts a mass dependence on isotopic mobility, but it is unknown how this translates into a mass dependence on effective binary diffusion coefficients, or more generally, the chemical diffusion coefficients that are housed in a multicomponent diffusion matrix. Our experiments are designed to measure Ca mobility, effective binary diffusion coefficients, the multicomponent diffusion matrix, and the effects of chemical diffusion on Ca isotopes in a liquid of single composition. We carried out two chemical diffusion experiments and one self-diffusion experiment, all at 1250 °C and 0.7 GPa and using a bulk composition for which other information is available from the literature. The self-diffusion experiment is used to determine the mobility of Ca in the absence of diffusive fluxes of other liquid components. The chemical diffusion experiments are designed to determine the effect on Ca isotope fractionation of changing the counter-diffusing component from fast-diffusing Na2O to slow-diffusing SiO2. When Na2O is the main counter-diffusing species, CaO diffusion is fast and larger Ca isotopic effects are generated. When SiO2 is the main counter-diffusing species, CaO diffusion is slow and smaller Ca isotopic effects are observed. In both experiments, the liquid is initially isotopically homogeneous, and during the experiment Ca isotopes become fractionated by diffusion. The results are used as a test of a new general expression for the diffusion of isotopes in a multicomponent liquid system that accounts for both self diffusion and the effects of counter-diffusing species. Our

  10. Chemical species of plutonium in Hanford radioactive tank waste

    SciTech Connect

    Barney, G.S.

    1997-10-22

    Large quantities of radioactive wastes have been generated at the Hanford Site over its operating life. The wastes with the highest activities are stored underground in 177 large (mostly one million gallon volume) concrete tanks with steel liners. The wastes contain processing chemicals, cladding chemicals, fission products, and actinides that were neutralized to a basic pH before addition to the tanks to prevent corrosion of the steel liners. Because the mission of the Hanford Site was to provide plutonium for defense purposes, the amount of plutonium lost to the wastes was relatively small. The best estimate of the amount of plutonium lost to all the waste tanks is about 500 kg. Given uncertainties in the measurements, some estimates are as high as 1,000 kg (Roetman et al. 1994). The wastes generally consist of (1) a sludge layer generated by precipitation of dissolved metals from aqueous wastes solutions during neutralization with sodium hydroxide, (2) a salt cake layer formed by crystallization of salts after evaporation of the supernate solution, and (3) an aqueous supernate solution that exists as a separate layer or as liquid contained in cavities between sludge or salt cake particles. The identity of chemical species of plutonium in these wastes will allow a better understanding of the behavior of the plutonium during storage in tanks, retrieval of the wastes, and processing of the wastes. Plutonium chemistry in the wastes is important to criticality and environmental concerns, and in processing the wastes for final disposal. Plutonium has been found to exist mainly in the sludge layers of the tanks along with other precipitated metal hydrous oxides. This is expected due to its low solubility in basic aqueous solutions. Tank supernate solutions do not contain high concentrations of plutonium even though some tanks contain high concentrations of complexing agents. The solutions also contain significant concentrations of hydroxide which competes with other

  11. Gas phase chemical detection with an integrated chemical analysis system

    SciTech Connect

    CASALNUOVO,STEPHEN A.; FRYE-MASON,GREGORY CHARLES; KOTTENSTETTE,RICHARD; HELLER,EDWIN J.; MATZKE,CAROLYN M.; LEWIS,PATRICK R.; MANGINELL,RONALD P.; BACA,ALBERT G.; HIETALA,VINCENT M.

    2000-04-12

    Microfabrication technology has been applied to the development of a miniature, multi-channel gas phase chemical laboratory that provides fast response, small size, and enhanced versatility and chemical discrimination. Each analysis channel includes a sample preconcentrator followed by a gas chromatographic separator and a chemically selective surface acoustic wave detector array to achieve high sensitivity and selectivity. The performance of the components, individually and collectively, is described.

  12. Chemical sensing in process analysis.

    PubMed

    Hirschfeld, T; Callis, J B; Kowalski, B R

    1984-10-19

    Improvements in process control, which determine production efficiency and product quality, are critically dependent upon on-line process analysis. The technology of the required instrumentation will be substantially expanded by advances in sensing devices. In the future, the hardware will consist of sensor arrays and miniaturized instruments fabricated by microlithography and silicon micromachining. Chemometrics will be extensively used in software to provide error detection, selfcalibration, and correction as well as multivariate data analysis for the determination of anticipated and unanticipated species. A number of examples of monolithically fabricated sensors now exist and more will be forthcoming as the new paradigms and new tools are widely adopted. A trend toward not only on-line but even in-product sensors is becoming discernible.

  13. Gas Phase Chemical Detection with an Integrated Chemical Analysis System

    SciTech Connect

    Baca, Albert G.; Casalnuovo, Stephen A.; Frye-Mason, Gregory C.; Heller, Edwin J.; Hietala, Susan L.; Hietala, Vincent M.; Kottenstette, Richard J.; Lewis, Patrick R.; Manginell, Ronald P.; Matzke, Carloyn M.; Reno, John L.; Sasaki, Darryl Y.; Schubert, W. Kent

    1999-07-08

    Microfabrication technology has been applied to the development of a miniature, multi-channel gas phase chemical laboratory that provides fast response, small size, and enhanced versatility and chemical discrimination. Each analysis channel includes a sample concentrator followed by a gas chromatographic separator and a chemically selective surface acoustic wave detector array to achieve high sensitivity and selectivity. The performance of the components, individually and collectively, is described. The design and performance of novel micromachined acoustic wave devices, with the potential for improved chemical sensitivity, are also described.

  14. Microorganisms in inorganic chemical analysis.

    PubMed

    Godlewska-Zyłkiewicz, Beata

    2006-01-01

    There are innumerable strains of microbes (bacteria, yeast and fungi) that degrade or transform chemicals and compounds into simpler, safer or less toxic substances. These bioprocesses have been used for centuries in the treatment of municipal wastes, in wine, cheese and bread making, and in bioleaching and metal recovery processes. Recent literature shows that microorganisms can be also used as effective sorbents for solid phase extraction procedures. This review reveals that fundamental nonanalytical studies on the parameters and conditions of biosorption processes and on metal-biomass interactions often result in efficient analytical procedures and biotechnological applications. Some selected examples illustrate the latest developments in the biosorption of metals by microbial biomass, which have opened the door to the application of microorganisms to analyte preconcentration, matrix separation and speciation analysis.

  15. Chemical variability in essential oils from Ruta species among seasons, and its taxonomic and ecological significance.

    PubMed

    Bennaoum, Zineb; Benhassaini, Hachemi; Falconieri, Danilo; Piras, Alessandra; Porcedda, Silvia

    2017-03-24

    Leaf essential oils of 11 samples from Ruta montana, Ruta chalepensis subsp. latifolia and Ruta chalepensis subsp. angustifolia collected from two sites have been studied by GC/MS that allowed to identify 22, 25 and 12 components, respectively. The variability in the composition of essential oils among species and seasons was very high, and hence the existence of different chemotypes has been inferred. The major components were 2-undecanone, (E) caryophyllene, 2-nonanone and 2-methyloctyl acetate. Multivariate analysis of the 11 samples suggest that the main factors capable to influence the chemical composition of leaf essential oils was both the collection period and the geographical origin. 2-Undecanone seems to be the chemotaxonomic marker of Ruta genus. Furthermore, the formation of distinct clusters and sub-clusters at high distance also supports that the patterns of distribution of chemical constituents among seasons can be used in delimiting species and infraspecific taxa within the species complexes.

  16. Measurement of mass distribution of chemical species in aerosol particles

    NASA Technical Reports Server (NTRS)

    Sinha, M. P.; Friedlander, S. K.

    1984-01-01

    Aerosols may be generated through the nebulizing of solutions and the evaporation of their solvent, leaving the dry solute particles. Attention is presently given to a method for the direct determination of the masses of chemical species in individual aerosol particles on a continuous, real-time basis, using mass spectrometry. After the aerosol particles are introduced into the ion source of a quadrupole mass spectrometer, the particles impinge on a hot rhenium filament in the mass spectrometer's ion source. The resulting vapor plume is ionized by electron bombardment, and a pulse of ions is generated by each particle. The intensities of different masses in the ion pulses can then be measured by the mass spectrometer.

  17. Chemical composition of some wild peanut species (Arachis L.) seeds.

    PubMed

    Grosso, N R; Nepote, V; Guzmán, C A

    2000-03-01

    Oil, protein, ash, and carbohydrate contents, iodine value, and fatty acid and sterol compositions were studied in seeds of Arachis trinitensis, A. chiquitana, A. kempff-mercadoi, A. diogoi, A. benensis, A. appressipila, A. valida, A. kretschmeri, A. helodes, A. kuhlmannii, A. williamsii, A. sylvestris, A. matiensis, A. pintoi, A. hoehnei, A. villosa, and A. stenosperma. Oil content was greatest in A.stenosperma (mean value = 51.8%). The protein level was higher in A. sylvestris (30.1%) and A. villosa (29.5%). Mean value of oleic acid varied between 30.6% (A. matiensis) and 46.8% (Arachis villosa), and linoleic acid oscillated between 34.1% (A. villosa) and 47.4% (A. appressipila). The better oleic-to-linoleic (O/L) ratio was exhibited by A. villosa (1.38). Some species showed higher concentration of behenic acid. The greatest level of this fatty acid was found in A. matiensis (6.2%). Iodine value was lower in A. valida (99.2). The sterol composition in the different peanut species showed higher concentration of beta-sitosterol (mean values oscillated between 55.7 and 60.2%) followed by campesterol (12.4-16. 5%), stigmasterol (9.7-13.3%), and Delta(5)-avenasterol (9.7-13.4%). The chemical quality and stability of oils (iodine value and O/L ratio) from wild peanut studied in this work are not better than those of cultivated peanut.

  18. Genetic diversity and chemical polymorphism of some Thymus species.

    PubMed

    Rustaiee, Ali Reza; Yavari, Alireza; Nazeri, Vahideh; Shokrpour, Majid; Sefidkon, Fatemeh; Rasouli, Musa

    2013-06-01

    To ascertain whether there are chemical and genetic relationships among some Thymus species and also to determine correlation between these two sets of data, the essential-oil composition and genetic variability of six populations of Thymus including: T. daenensis ČELAK. (two populations), T. fallax FISCH. & C.A.MEY., T. fedtschenkoi RONNIGER, T. migricus KLOKOV & DES.-SHOST., and T. vulgaris L. were analyzed by GC and GC/MS, and also by randomly amplified polymorphic DNA (RAPD). Thus, 27 individuals were analyzed using 16 RAPD primers, which generated 264 polymorphic scorable bands and volatiles isolated by distillation extraction were subjected to GC and GC/MS analyses. The yields of oils ranged from 2.1 to 3.8% (v/w), and 34 components were identified, amounting to a total percentage of 97.8-99.9%. RAPD Markers allowed a perfect distinction between the different species based on their distinctive genetic background. However, they did not show identical clustering with the volatile-oil profiles.

  19. Concordant chemical reaction networks and the Species-Reaction Graph.

    PubMed

    Shinar, Guy; Feinberg, Martin

    2013-01-01

    In a recent paper it was shown that, for chemical reaction networks possessing a subtle structural property called concordance, dynamical behavior of a very circumscribed (and largely stable) kind is enforced, so long as the kinetics lies within the very broad and natural weakly monotonic class. In particular, multiple equilibria are precluded, as are degenerate positive equilibria. Moreover, under certain circumstances, also related to concordance, all real eigenvalues associated with a positive equilibrium are negative. Although concordance of a reaction network can be decided by readily available computational means, we show here that, when a nondegenerate network's Species-Reaction Graph satisfies certain mild conditions, concordance and its dynamical consequences are ensured. These conditions are weaker than earlier ones invoked to establish kinetic system injectivity, which, in turn, is just one ramification of network concordance. Because the Species-Reaction Graph resembles pathway depictions often drawn by biochemists, results here expand the possibility of inferring significant dynamical information directly from standard biochemical reaction diagrams.

  20. Concordant Chemical Reaction Networks and the Species-Reaction Graph

    PubMed Central

    Shinar, Guy; Feinberg, Martin

    2015-01-01

    In a recent paper it was shown that, for chemical reaction networks possessing a subtle structural property called concordance, dynamical behavior of a very circumscribed (and largely stable) kind is enforced, so long as the kinetics lies within the very broad and natural weakly monotonic class. In particular, multiple equilibria are precluded, as are degenerate positive equilibria. Moreover, under certain circumstances, also related to concordance, all real eigenvalues associated with a positive equilibrium are negative. Although concordance of a reaction network can be decided by readily available computational means, we show here that, when a nondegenerate network’s Species-Reaction Graph satisfies certain mild conditions, concordance and its dynamical consequences are ensured. These conditions are weaker than earlier ones invoked to establish kinetic system injectivity, which, in turn, is just one ramification of network concordance. Because the Species-Reaction Graph resembles pathway depictions often drawn by biochemists, results here expand the possibility of inferring significant dynamical information directly from standard biochemical reaction diagrams. PMID:22940368

  1. Chemical defense and chemical variation in some tropical Pacific species of Halimeda (Halimedaceae; Chlorophyta)

    NASA Astrophysics Data System (ADS)

    Paul, Valerie J.; van Alstyne, Kathryn L.

    1988-03-01

    Over a dozen species of the genus Halimeda have been chemically investigated and found to produce the diterpenoid metabolites halimedatrial (1) and halimedatetraacetate (2) in varying concentrations. These meabolites have been proposed to play a role in chemical defense against herbivores based on their chemical structures and their demonstrated biological activities in laboratory and aquarium assays. We examined and compared the feeding deterrent effects of these two compounds tovard herbivorous fishes in field experiments on Guam reefs. Halimedatrial is a more effective feeding deterrent than halimedatetraacetate. It is the major secondary metabolite in young Halimeda macroloba and in the newly produced segments of growing plants. The organic extracts from young plants and new segments were significantly more deterrent than extracts from mature plant tissue. Some populations of Halimeda growing in reef-slope habitats, where herbivory is intense, also have high concentrations of halimedatrial. We compared extracts between reef slope and reef flat collections of Halimeda opuntia on Guam and Pohnpei (= Ponape), and H. discoidea and H. macroloba on Guam. We found that halimedtrial was the major metabolite in reef-slope collections of H. opuntia from Pohnpei and Pago Bay, Guam, and that halimedatetraacetate was the major metabolite a non-reef slope populations. In the cases examined, chemical defenses were greatest in (1) plant parts and (2) populations that were at greatest risk to herbivores.

  2. Chemical constituents and biological activities of two Iranian Cystoseira species.

    PubMed

    Yegdaneh, Afsaneh; Ghannadi, Alireza; Dayani, Ladan

    2016-07-01

    The marine environment represents approximately half of the global biodiversity and could provide unlimited biological resources for the production of therapeutic drugs. Marine seaweeds comprise few thousands of species representing a considerable part of the littoral biomass. Extracts of the Cystoseira indica and Cystoseira merica were subjected to phytochemical and cytotoxicity evaluation. The amount of total phenol was determined with Folin-Ciocalteu reagent. Cytotoxicity was characterized by IC50 of human cancer cell lines including MCF-7 (human breast adenocarcinoma), HeLa (cervical carcinoma), and HT-29 (human colon adenocarcinoma) using Sulforhodamin assay. Antioxidant activities were evaluated using 2,2-diphenylpicrylhydrazyl (DPPH) method. The analysis revealed that tannins, saponins, sterols and triterpenes were the most abundant constituents in these Cystoseira species while cyanogenic and cardiac glycosides were the least ones. C. indica had the higher content of total phenolics and also showed higher antioxidant activity. Cytotoxic results showed that both species inhibited cell growth effectively, especially against MCF-7 cell line. The present findings suggest potential pharmacological applications of selected seaweeds but require further investigation and identification of their bioactive principles.

  3. Chemical constituents and biological activities of two Iranian Cystoseira species

    PubMed Central

    Yegdaneh, Afsaneh; Ghannadi, Alireza; Dayani, Ladan

    2016-01-01

    The marine environment represents approximately half of the global biodiversity and could provide unlimited biological resources for the production of therapeutic drugs. Marine seaweeds comprise few thousands of species representing a considerable part of the littoral biomass. Extracts of the Cystoseira indica and Cystoseira merica were subjected to phytochemical and cytotoxicity evaluation. The amount of total phenol was determined with Folin-Ciocalteu reagent. Cytotoxicity was characterized by IC50 of human cancer cell lines including MCF-7 (human breast adenocarcinoma), HeLa (cervical carcinoma), and HT-29 (human colon adenocarcinoma) using Sulforhodamin assay. Antioxidant activities were evaluated using 2,2-diphenylpicrylhydrazyl (DPPH) method. The analysis revealed that tannins, saponins, sterols and triterpenes were the most abundant constituents in these Cystoseira species while cyanogenic and cardiac glycosides were the least ones. C. indica had the higher content of total phenolics and also showed higher antioxidant activity. Cytotoxic results showed that both species inhibited cell growth effectively, especially against MCF-7 cell line. The present findings suggest potential pharmacological applications of selected seaweeds but require further investigation and identification of their bioactive principles. PMID:27651811

  4. Comparing bee species responses to chemical mixtures: Common response patterns?

    PubMed Central

    Lahive, Elma; Horton, Alice A.; Svendsen, Claus; Rortais, Agnes; Dorne, Jean Lou; Baas, Jan; Heard, Matthew S.; Spurgeon, David J.

    2017-01-01

    Pollinators in agricultural landscapes can be exposed to mixtures of pesticides and environmental pollutants. Existing mixture toxicity modelling approaches, such as the models of concentration addition and independent action and the mechanistic DEBtox framework have been previously shown as valuable tools for understanding and ultimately predicting joint toxicity. Here we apply these mixture models to investigate the potential to interpret the effects of semi-chronic binary mixture exposure for three bee species: Apis mellifera, Bombus terrestris and Osmia bicornis within potentiation and mixture toxicity experiments. In the potentiation studies, the effect of the insecticide dimethoate with added propiconazole fungicide and neonicotinoid insecticide clothianidin with added tau-fluvalinate pyrethroid acaricide showed no difference in toxicity compared to the single chemical alone. Clothianidin toxicity showed a small scale, but temporally conserved increase in exposure conducted in the presence of propiconazole, particularly for B. terrestris and O. bicornis, the latter showing a near three-fold increase in clothianidin toxicity in the presence of propiconazole. In the mixture toxicity studies, the dominant response patterns were of additivity, however, binary mixtures of clothianidin and dimethoate in A. mellifera, B. terrestris and male O. bicornis there was evidence of a predominant antagonistic interaction. Given the ubiquitous nature of exposures to multiple chemicals, there is an urgent need to consider mixture effects in pollinator risk assessments. Our analyses suggest that current models, particularly those that utilise time-series data, such as DEBtox, can be used to identify additivity as the dominant response pattern and also those examples of interactions, even when small-scale, that may need to be taken into account during risk assessment. PMID:28640811

  5. Spectroscopic chemical analysis methods and apparatus

    NASA Technical Reports Server (NTRS)

    Hug, William F. (Inventor); Reid, Ray D. (Inventor)

    2010-01-01

    Spectroscopic chemical analysis methods and apparatus are disclosed which employ deep ultraviolet (e.g. in the 200 nm to 300 nm spectral range) electron beam pumped wide bandgap semiconductor lasers, incoherent wide bandgap semiconductor light emitting devices, and hollow cathode metal ion lasers to perform non-contact, non-invasive detection of unknown chemical analytes. These deep ultraviolet sources enable dramatic size, weight and power consumption reductions of chemical analysis instruments. Chemical analysis instruments employed in some embodiments include capillary and gel plane electrophoresis, capillary electrochromatography, high performance liquid chromatography, flow cytometry, flow cells for liquids and aerosols, and surface detection instruments. In some embodiments, Raman spectroscopic detection methods and apparatus use ultra-narrow-band angle tuning filters, acousto-optic tuning filters, and temperature tuned filters to enable ultra-miniature analyzers for chemical identification. In some embodiments Raman analysis is conducted simultaneously with native fluorescence spectroscopy to provide high levels of sensitivity and specificity in the same instrument.

  6. Spectroscopic chemical analysis methods and apparatus

    NASA Technical Reports Server (NTRS)

    Hug, William F. (Inventor); Reid, Ray D. (Inventor)

    2009-01-01

    Spectroscopic chemical analysis methods and apparatus are disclosed which employ deep ultraviolet (e.g. in the 200 nm to 300 nm spectral range) electron beam pumped wide bandgap semiconductor lasers, incoherent wide bandgap semiconductor light emitting devices, and hollow cathode metal ion lasers to perform non-contact, non-invasive detection of unknown chemical analytes. These deep ultraviolet sources enable dramatic size, weight and power consumption reductions of chemical analysis instruments. Chemical analysis instruments employed in some embodiments include capillary and gel plane electrophoresis, capillary electrochromatography, high performance liquid chromatography, flow cytometry, flow cells for liquids and aerosols, and surface detection instruments. In some embodiments, Raman spectroscopic detection methods and apparatus use ultra-narrow-band angle tuning filters, acousto-optic tuning filters, and temperature tuned filters to enable ultra-miniature analyzers for chemical identification. In some embodiments Raman analysis is conducted simultaneously with native fluorescence spectroscopy to provide high levels of sensitivity and specificity in the same instrument.

  7. Chemical classification of the essential oils of the Iranian Salvia species in comparison with their botanical taxonomy.

    PubMed

    Jassbi, Amir Reza; Asadollahi, Mojtaba; Masroor, Mahdi; Schuman, Meredith C; Mehdizadeh, Zeynab; Soleimani, Mahboobeh; Miri, Ramin

    2012-07-01

    The essential oils of eight Salvia species collected from different localities in Iran were analyzed by gas chromatography/mass spectrometry (GC/MS). The analytical results were compared with those previously published for related Iranian sage species in order to identify chemical markers for these species. Salvia eremophila, S. hypoleuca, and S. reuteriana are endemic, while S. atropatana, S. chloroleuca, S. santolinifolia, S. aegyptiaca, and S. macrosiphon also grow wild in neighboring countries. We categorized the Iranian Salvia species into four main chemotypes according to their essential-oil constituents: those which are dominated by 1) monoterpenes, 2) mono- and sesquiterpenes, or 3) sesquiterpenes as the major constituents, and 4) those containing low-molecular-weight acids, aldehydes, and esters, and green-leaf volatiles (GLVs). Likely due to the chemical diversity of different Salvia chemotypes, this categorization was supported by principal component analysis (PCA) for the group sampled here, but not for the values reported in the literature. We identified the following chemical markers: α-pinene, β-pinene, 1,8-cineol, linalool, and borneol in monoterpene-rich species, or β-caryophyllene, germacrene D, bicyclogermacrene, spathulenol, and caryophyllene oxide in sesquiterpene-rich species. Among these, α-pinene, β-caryophyllene, and germacrene D are the most common and abundant in the Salvia species investigated. In accordance with their close biological taxonomy, the chemical similarity of the essential oils of S. santolinifolia and S. eremophila is so high that we may consider them chemically identical.

  8. STRAW: Species TRee Analysis Web server

    PubMed Central

    Shaw, Timothy I.; Ruan, Zheng; Glenn, Travis C.; Liu, Liang

    2013-01-01

    The coalescent methods for species tree reconstruction are increasingly popular because they can accommodate coalescence and multilocus data sets. Herein, we present STRAW, a web server that offers workflows for reconstruction of phylogenies of species using three species tree methods—MP-EST, STAR and NJst. The input data are a collection of rooted gene trees (for STAR and MP-EST methods) or unrooted gene trees (for NJst). The output includes the estimated species tree, modified Robinson-Foulds distances between gene trees and the estimated species tree and visualization of trees to compare gene trees with the estimated species tree. The web sever is available at http://bioinformatics.publichealth.uga.edu/SpeciesTreeAnalysis/. PMID:23661681

  9. Dealing with Uncertainty in Chemical Risk Analysis

    DTIC Science & Technology

    1988-12-01

    0 * (OF 41 C-DEALING WITH UNCERTAINTY IN - CHEMICAL RISK ANALYSIS THESIS David S. Clement Captain, USAF AFIT/GOR/MA/8CD-2 DT[C. ~ELECTEf 2 9 MAR 18...AFIT/GOR/MA/88D-2 DEALING WITH UNCERTAINTY IN CHEMICAL RISK ANALYSIS THESIS David S. Clement Captain, USAF AFIT/GOR/MA/88D-2 DTIC V ~ 27989 Approved...for public release; distribution unlimited S . AFIT/GOR/KA/88D-2 DEALING WITH UNCERTAINTY IN CHEMICAL RISK ANALYSIS THESIS Presented to the Faculty

  10. Biomonitoring of chemical elements in an urban environment using arboreal and bush plant species.

    PubMed

    Rucandio, Maria Isabel; Petit-Domínguez, Maria Dolores; Fidalgo-Hijano, Concepcion; García-Giménez, Rosario

    2011-01-01

    The aim of this work was to investigate the possibility of using several bush and arboreal plant species, usually present as ornamental plants in street and parks, as environmental indicators of pollution. This is a research paper that evaluates the real possibility of using a fast and low-cost procedure to evaluate the pollution degree through data obtained from plant species growing within an urban environment. Leaves of six different bush and arboreal species were collected from different parts of Madrid (Spain), ranging from highly polluted considered areas to medium and low contaminated ones. A total of 66 chemical elements, from major to minor and trace, were determined for every leaf sample by inductively coupled plasma-mass spectrometry. Statistical analyses were carried out using mainly box and whisker plots, linear discriminant analysis and cluster analysis. The pollution by different elements of the studied areas of Madrid cannot be considered generally dangerous for human health. The level detected for the contaminants, in general, is similar or lower than other urban cities. Pb and V concentrations in plant samples tend to increase as traffic density increases. The different studied plant species showed a different capability of accumulation of certain elements. Cedrus deodara accumulates specially Ag, Hg, Mo and V; Cupressus sempervirens, Zr; Pinus pinea, As and Sb; Nerium oleander Ni, Pb, Mo and Se; Ligustrum ovalifolium, Sc and V; and Pittosporum tobira, Ag, Cd, Rb and Sc. The leaves and needles collected from bush and arboreal plants common in this city have demonstrated to be useful to evaluate the level of pollution not only through the chemical analysis but also through the recognition of the visual injury symptoms. The application of multivariate statistical techniques combined with determining of element concentration and correlation analysis has been proved to be an effective tool for reach the objectives of the present work. This allows

  11. 40 CFR 761.253 - Chemical analysis.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Chemical analysis. 761.253 Section 761.253 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT... Sample Sites, Collecting Surface Samples, and Analyzing Standard PCB Wipe Samples § 761.253 Chemical...

  12. Instrumentation for chemical species measurements in the troposphere and stratosphere

    SciTech Connect

    Kolb, C.E. )

    1991-01-01

    Instrument advances made during 1987-1990 for atmospheric trace species measurements are reviewed. Problems discussed include types of measurement strategies, oxidant species, reductant species, and flux measurement. Particular attention is given to odd oxygen species, hydrogen oxides, hydrocarbon oxy and peroxy radicals, halogen oxides, sulfur oxides, carbon monoxides, hydrocarbons, oxygenated hydrocarbons, halogenated hydrocarbons, reduced sulfur compounds, ammonia, cyanide compounds, water vapor, nitrous oxide, hydrogen halides, fully halogenated carbon compounds, fully halogenated carbonyl compounds, and sulfur hexafluoride. 195 refs.

  13. Vesicle-based method and apparatus for collecting, manipulating, and chemically processing trace macromolecular species

    DOEpatents

    Davalos, Rafael V.; Ellis, Christopher R. B.

    2008-03-04

    Disclosed is an apparatus and method for inserting one or several chemical or biological species into phospholipid containers that are controlled within a microfluidic network, wherein individual containers are tracked and manipulated by electric fields and wherein the contained species may be chemically processed.

  14. Vesicle-based method for collecting, manipulating, and chemically processing trace macromolecular species

    DOEpatents

    Davalos, Rafael V [Oakland, CA; Ellis, Christopher R. B. [Oakland, CA

    2010-08-17

    Disclosed is an apparatus and method for inserting one or several chemical or biological species into phospholipid containers that are controlled within a microfluidic network, wherein individual containers are tracked and manipulated by electric fields and wherein the contained species may be chemically processed.

  15. An efficient approach for limited-data chemical species tomography and its error bounds

    PubMed Central

    Polydorides, N.; Tsekenis, S.-A.; McCann, H.; Prat, V.-D. A.; Wright, P.

    2016-01-01

    We present a computationally efficient reconstruction method for the limited-data chemical species tomography problem that incorporates projection of the unknown gas concentration function onto a low-dimensional subspace, and regularization using prior information obtained from a simple flow model. In this context, the contribution of this work is on the analysis of the projection-induced data errors and the calculation of bounds for the overall image error incorporating the impact of projection and regularization errors as well as measurement noise. As an extension to this methodology, we present a variant algorithm that preserves the positivity of the concentration image. PMID:27118923

  16. Spectroscopic Chemical Analysis Methods and Apparatus

    NASA Technical Reports Server (NTRS)

    Hug, William F. (Inventor); Reid, Ray D. (Inventor); Bhartia, Rohit (Inventor); Lane, Arthur L. (Inventor)

    2017-01-01

    Spectroscopic chemical analysis methods and apparatus are disclosed which employ deep ultraviolet (e.g. in the 200 nm to 300 nm spectral range) electron beam pumped wide bandgap semiconductor lasers, incoherent wide bandgap semiconductor light emitting devices, and hollow cathode metal ion lasers to perform non-contact, non-invasive detection of unknown chemical analytes. These deep ultraviolet sources enable dramatic size, weight and power consumption reductions of chemical analysis instruments. In some embodiments, Raman spectroscopic detection methods and apparatus use ultra-narrow-band angle tuning filters, acousto-optic tuning filters, and temperature tuned filters to enable ultra-miniature analyzers for chemical identification. In some embodiments Raman analysis is conducted along with photoluminescence spectroscopy (i.e. fluorescence and/or phosphorescence spectroscopy) to provide high levels of sensitivity and specificity in the same instrument.

  17. Chemical recognition of partner plant species by foundress ant queens in Macaranga-Crematogaster myrmecophytism.

    PubMed

    Inui, Y; Itioka, T; Murase, K; Yamaoka, R; Itino, T

    2001-10-01

    The partnership in the Crematogaster-Macaranga ant-plant interaction is highly species-specific. Because a mutualistic relationship on a Macaranga plant starts with colonization by a foundress queen of a partner Crematogaster species, we hypothesized that the foundress queens select their partner plant species by chemical recognition. We tested this hypothesis with four sympatric Macaranga species and their Crematogaster plant-ant species. We demonstrated that foundress Crematogaster queens can recognize their partner Macaranga species by contact with the surface of the seedlings, that they can recognize compounds from the stem surface of seedlings of their partner plant species, and that the gas chromatographic profiles are characteristic of the plant species. These findings support the hypothesis that foundress queens of the Crematogaster plant-ant species select their partner Macaranga species by recognizing nonvolatile chemical characteristics of the stem surfaces of seedlings.

  18. Sample processor for chemical analysis

    NASA Technical Reports Server (NTRS)

    Boettger, Heinz G. (Inventor)

    1980-01-01

    An apparatus is provided which can process numerous samples that must be chemically analyzed by the application of fluids such as liquid reagents, solvents and purge gases, as well as the application of dumps for receiving the applied fluid after they pass across the sample, in a manner that permits numerous samples to be processed in a relatively short time and with minimal manpower. The processor includes a rotor which can hold numerous cartridges containing inert or adsorbent material for holding samples, and a pair of stators on opposite sides of the rotor. The stators form stations spaced along the path of the cartridges which lie in the rotor, and each station can include an aperture in one stator through which a fluid can be applied to a cartridge resting at that station, and an aperture in the other stator which can receive the fluid which has passed through the cartridge. The stators are sealed to the ends of the cartridges lying on the rotor, to thereby isolate the stations from one another.

  19. Relations between chemical species distribution and the fluctuating activity of Vulcano (Italy)

    NASA Astrophysics Data System (ADS)

    Martini, Marino; Cellini Legittimo, Paola

    1984-09-01

    Five years of systematic observation of the fumaroles of Vulcano have allowed us to detect some compositional trends coincident with a fluctuation in temperature. A gradual decrease of CO 2, H 2S+SO 2, HF is observed with the lowering of temperature, while HCl slightly increases. These physical-chemical characters of the system are not readily explained as simply produced by different stages in magma degassing, and the previous hypothesis of the significant influence of a brackish aquifer on the fumaroles still appears a reliable working model. R-mode factor analysis allowed to distinguish the differentiated role of chemical species for which different genetic processes can be derived. The ratios {HF}/{HCl} and {SO 2}/{H 2S } are taken as indicators of the changing activity of the system, and also the available data for Usu (Japan) and Mount St. Helens (USA) are considered.

  20. Chemical toxicity correlations for several fish species based on the Abraham solvation parameter model.

    PubMed

    Hoover, Kaci R; Acree, William E; Abraham, Michael H

    2005-09-01

    The Abraham solvation parameter model is used to construct mathematical correlations for describing the nonspecific aquatic toxicity of organic compounds to the fathead minnow, guppy, bluegill, goldfish, golden orfe, and high-eyes medaka. The derived mathematical correlations describe the observed published toxicity data to within an overall average standard deviation of approximately 0.28 log units. In the case of ester solutes, the descriptions were improved by introducing an indicator variable into the basic model. Derived correlations can be used to estimate aquatic toxicities of organic chemicals to the six fish species studied and to help in identifying compounds whose toxic mode of action might involve chemical specific reactivity, rather than nonpolar or polar narcosis. A principal component analysis of the correlation equations shows that the water-octanol system is a poor model for nonspecific aquatic toxicity but that the water-isobutanol and water-pentanol systems are much better models.

  1. Modeling non-isothermal multiphase multi-species reactive chemical transport in geologic media

    SciTech Connect

    Tianfu Xu; Gerard, F.; Pruess, K.; Brimhall, G.

    1997-07-01

    The assessment of mineral deposits, the analysis of hydrothermal convection systems, the performance of radioactive, urban and industrial waste disposal, the study of groundwater pollution, and the understanding of natural groundwater quality patterns all require modeling tools that can consider both the transport of dissolved species as well as their interactions with solid (or other) phases in geologic media and engineered barriers. Here, a general multi-species reactive transport formulation has been developed, which is applicable to homogeneous and/or heterogeneous reactions that can proceed either subject to local equilibrium conditions or kinetic rates under non-isothermal multiphase flow conditions. Two numerical solution methods, the direct substitution approach (DSA) and sequential iteration approach (SIA) for solving the coupled complex subsurface thermo-physical-chemical processes, are described. An efficient sequential iteration approach, which solves transport of solutes and chemical reactions sequentially and iteratively, is proposed for the current reactive chemical transport computer code development. The coupled flow (water, vapor, air and heat) and solute transport equations are also solved sequentially. The existing multiphase flow code TOUGH2 and geochemical code EQ3/6 are used to implement this SIA. The flow chart of the coupled code TOUGH2-EQ3/6, required modifications of the existing codes and additional subroutines needed are presented.

  2. Chemical properties in fruits of mulberry species from the Xinjiang province of China.

    PubMed

    Jiang, Yan; Nie, Wen-Jing

    2015-05-01

    Mulberries are a widely cultivated foodstuff both in China and worldwide. However, there are stark differences in the nutritional values of mulberry species. To better appreciate these differences, we here describe the chemical characteristics of white (Morus alba L.), Russian (M. alba var. tatarica L.), and black (Morus nigra L.) mulberry fruits cultivated in the Xinjiang province of China. The chemical composition analysis was performed by official methods procedures. The amino acids were analysed by the phenyl isothiocyanate method. The 2,6-dichloroindophenol titrimetric method, the aluminium chloride colorimetric method, and the pH differential method were also used in measuring the content of reduced ascorbic acid, total flavonoids, and total monomeric anthocyanins, respectively. The black mulberry fruits had the highest content of reduced ascorbic acid (48.4 mg/100 g fw), titratable acidity (47.1 mg/g fw), and Fe (11.9 mg/100 g fw) of these 3 species. The Russian mulberry fruits had the highest EAA/TAA (essential amino acid/total amino acid) ratio at 44% followed by the white mulberry (42%) and the black mulberry (29%). The black mulberry fruits had found to be richest in terms of total flavonoids and total monomeric anthocyanins. These results are helpful for selecting mulberry species with abundant nutrients and phytochemicals for commercial cultivation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Phytotoxic Activity and Chemical Composition of Aqueous Volatile Fractions from Eucalyptus Species

    PubMed Central

    Zhang, Jinbiao; An, Min; Wu, Hanwen; Liu, De Li; Stanton, Rex

    2014-01-01

    The essential oils from four Eucalyptus species (E. spathulata, E. salubris, E. brockwayii and E. dundasii) have been previously confirmed to have stronger inhibitory effects on germination and seedling growth of silverleaf nightshade (Solanum elaeagnifolium Cav.). The aqueous volatile fractions (AVFs) were the water soluble volatile fractions produced together with the essential oils (water insoluble fractions) during the steam distillation process. The aim of this study was to further assess the phytotoxicity of AVFs from the four Eucalyptus species and their chemical composition. The fresh leaves of the four Eucalyptus species were used for the extraction of AVFs. The AVFs were tested for their phytotoxic effects on the perennial weed, silverleaf nightshade under laboratory conditions. The chemical compositions of the AVFs were determined by gas chromatograph–mass spectrometry (GC-MS). Our results showed that the AVFs had strong inhibition on the germination and seedling growth of silverleaf nightshade. The inhibition index increased with the increasing concentrations of AVFs. The inhibitory effects of the AVFs varied between different Eucalyptus species. The AVF from E. salubris demonstrated the highest inhibitory activity on the weed tested, with complete inhibition on germination and seedling growth at a concentration of 75%. The GC-MS analysis revealed that 1,8-cineole, isopentyl isovalerate, isomenthol, pinocarvone, trans-pinocarveol, alpha-terpineol and globulol were the main compounds in the AVFs. These results indicated that all AVFs tested had differential inhibition on the germination and seedling growth of silverleaf nightshade, which could be due to the joint effects of compounds present in the AVFs as these compounds were present in different quantities and ratio between Eucalyptus species. PMID:24681490

  4. Phytotoxic activity and chemical composition of aqueous volatile fractions from Eucalyptus species.

    PubMed

    Zhang, Jinbiao; An, Min; Wu, Hanwen; Liu, De Li; Stanton, Rex

    2014-01-01

    The essential oils from four Eucalyptus species (E. spathulata, E. salubris, E. brockwayii and E. dundasii) have been previously confirmed to have stronger inhibitory effects on germination and seedling growth of silverleaf nightshade (Solanum elaeagnifolium Cav.). The aqueous volatile fractions (AVFs) were the water soluble volatile fractions produced together with the essential oils (water insoluble fractions) during the steam distillation process. The aim of this study was to further assess the phytotoxicity of AVFs from the four Eucalyptus species and their chemical composition. The fresh leaves of the four Eucalyptus species were used for the extraction of AVFs. The AVFs were tested for their phytotoxic effects on the perennial weed, silverleaf nightshade under laboratory conditions. The chemical compositions of the AVFs were determined by gas chromatograph-mass spectrometry (GC-MS). Our results showed that the AVFs had strong inhibition on the germination and seedling growth of silverleaf nightshade. The inhibition index increased with the increasing concentrations of AVFs. The inhibitory effects of the AVFs varied between different Eucalyptus species. The AVF from E. salubris demonstrated the highest inhibitory activity on the weed tested, with complete inhibition on germination and seedling growth at a concentration of 75%. The GC-MS analysis revealed that 1,8-cineole, isopentyl isovalerate, isomenthol, pinocarvone, trans-pinocarveol, alpha-terpineol and globulol were the main compounds in the AVFs. These results indicated that all AVFs tested had differential inhibition on the germination and seedling growth of silverleaf nightshade, which could be due to the joint effects of compounds present in the AVFs as these compounds were present in different quantities and ratio between Eucalyptus species.

  5. Electron Spectroscopy for Chemical Analysis (ESCA) study of atmospheric particles

    NASA Technical Reports Server (NTRS)

    Dillard, J. G.; Seals, R. D.; Wightman, J. P.

    1979-01-01

    The results of analyses by ESCA (Electron Spectroscopy for Chemical Analysis) on several Nuclepore filters which were exposed during air pollution studies are presented along with correlative measurements by Neutron Activation Analysis and Scanning Electron Microscopy. Samples were exposed during air pollution studies at Norfolk, Virginia and the NASA Kennedy Space Center (KSC). It was demonstrated that with the ESCA technique it was possible to identify the chemical (bonding) state of elements contained in the atmospheric particulate matter collected on Nuclepore filters. Sulfur, nitrogen, mercury, chlorine, alkali, and alkaline earth metal species were identified in the Norfolk samples. ESCA binding energy data for aluminum indicated that three chemically different types of aluminum are present in the launch and background samples from NASA-KSC.

  6. Chemical Analysis Of Beryllium Shells

    SciTech Connect

    Gunther, J; Cook, R

    2005-11-17

    There is a need to understand the level of high-Z impurities in Beryllium shells prepared by sputter coating. The Ignition Point Design Requirements state the following: ''Except for allowed ingredients, as listed in the ablator composition entries, the ablator material in all layers shall contain sufficiently low impurity levels that the sum over all impurities of atom fraction*Z{sup 2} shall be less than or equal to 0.2''. This is a tight specification that requires careful materials analysis. Early in the first quarter of FY06, we undertook a study of Be shell impurities via ICP-MS{sup 2} and determined that the impurity levels in the sputtered shells are very close to the specification.

  7. Different chemical cues originating from a shared predator induce common defense responses in two prey species.

    PubMed

    Takahara, Teruhiko; Doi, Hideyuki; Kohmatsu, Yukihiro; Yamaoka, Ryohei

    2013-01-01

    In freshwater ecosystems, inducible defenses that involve behavioral or morphological changes in response to chemical cue detection are key phenomena in prey-predator interactions. Many species with different phylogenetic and ecological traits (e.g., general activity patterns and microhabitats) use chemical cues to avoid predators. We hypothesized that prey species with a shared predator, but having different ecological traits, would be adapted to detect different chemical cues from the predator. However, the proximate mechanisms by which prey use chemical cues to avoid predation remain little known. Here, we tested our hypothesis by using fractionated chemical components from predatory dragonfly nymphs (Lesser Emperor, Anax parthenope julius) to trigger anti-predator behavioral responses in two anuran tadpoles, the wrinkled frog Glandirana (Rana) rugosa and the Japanese tree frog Hyla japonica. Glandirana rugosa detected chemical cues that had either high or low hydrophobic properties, but H. japonica responded only to chemical cues with hydrophilic properties. During the normal behaviors of these tadpole species, G. rugosa remains immobile in benthic habitats, whereas H. japonica exhibits active swimming at the surface or in the middle of the water column. As we had hypothesized, these tadpole species, which have different general activity levels and microhabitats, detected different chemical cues that were exuded by their shared predator and responded by changing their activities to avoid predation. The specific chemical cues detected by each tadpole species are likely to have characteristics that optimize effective predator detection and encounter avoidance of the shared dragonfly predator.

  8. Spectroscopic chemical analysis methods and apparatus

    NASA Technical Reports Server (NTRS)

    Hug, William F. (Inventor); Reid, Ray D. (Inventor); Bhartia, Rohit (Inventor)

    2013-01-01

    Spectroscopic chemical analysis methods and apparatus are disclosed which employ deep ultraviolet (e.g. in the 200 nm to 300 nm spectral range) electron beam pumped wide bandgap semiconductor lasers, incoherent wide bandgap semiconductor light emitting devices, and hollow cathode metal ion lasers to perform non-contact, non-invasive detection of unknown chemical analytes. These deep ultraviolet sources enable dramatic size, weight and power consumption reductions of chemical analysis instruments. Chemical analysis instruments employed in some embodiments include capillary and gel plane electrophoresis, capillary electrochromatography, high performance liquid chromatography, flow cytometry, flow cells for liquids and aerosols, and surface detection instruments. In some embodiments, Raman spectroscopic detection methods and apparatus use ultra-narrow-band angle tuning filters, acousto-optic tuning filters, and temperature tuned filters to enable ultra-miniature analyzers for chemical identification. In some embodiments Raman analysis is conducted along with photoluminescence spectroscopy (i.e. fluorescence and/or phosphorescence spectroscopy) to provide high levels of sensitivity and specificity in the same instrument.

  9. Chemical equilibrium of ablation materials including condensed species

    NASA Technical Reports Server (NTRS)

    Stroud, C. W.; Brinkley, K. L.

    1975-01-01

    Equilibrium is determined by finding chemical composition with minimum free energy. Method of steepest descent is applied to quadratic representation of free-energy surface. Solution is initiated by selecting arbitrary set of mole fractions, from which point on free-energy surface is computed.

  10. Chemical Diversity, Biological Activity, and Genetic Aspects of Three Ocotea Species from the Amazon.

    PubMed

    da Silva, Joyce Kelly; da Trindade, Rafaela; Moreira, Edith Cibelle; Maia, José Guilherme S; Dosoky, Noura S; Miller, Rebecca S; Cseke, Leland J; Setzer, William N

    2017-05-18

    Ocotea species present economic importance and biological activities attributed to their essential oils (EOs) and extracts. For this reason, various strategies have been developed for their conservation. The chemical compositions of the essential oils and matK DNA sequences of O. caudata, O. cujumary, and O. caniculata were subjected to comparison with data from O. floribunda, O. veraguensis, and O. whitei, previously reported. The multivariate analysis of chemical composition classified the EOs into two main clusters. Group I was characterized by the presence of α-pinene (9.8-22.5%) and β-pinene (9.7-21.3%) and it includes O. caudata, O. whitei, and O. floribunda. In group II, the oils of O. cujumary and O. caniculata showed high similarity due amounts of β-caryophyllene (22.2% and 18.9%, respectively). The EO of O. veraguensis, rich in p-cymene (19.8%), showed minor similarity among all samples. The oils displayed promising antimicrobial and cytotoxic activities against Escherichia coli (minimum inhibitory concentration (MIC) < 19.5 µg·mL(-1)) and MCF-7 cells (median inhibitory concentration (IC50) ≅ 65.0 µg·mL(-1)), respectively. The analysis of matK gene displayed a good correlation with the main class of chemical compounds present in the EOs. However, the matK gene data did not show correlation with specific compounds.

  11. Microbiological and Chemical Analysis of Land Snails Commercialised in Sicily

    PubMed Central

    Cicero, Antonello; Giangrosso, Giuseppe; Cammilleri, Gaetano; Macaluso, Andrea; Currò, Vittoria; Galuppo, Lucia; Vargetto, Daniela; Vicari, Domenico

    2015-01-01

    In this study 160 samples of snails belonging to the species Helix aspersa maxima and Helix aspersa muller were examined for chemical and microbiological analysis. Samples came from Greece and Poland. Results showed mean concentration of cadmium (0.35±0.036 mg/kg) and lead (0.05±0.013 mg/kg) much higher than the limit of detection. Mercury levels in both species were not detected. Microbiological analysis revealed the absence of Salmonella spp. and Clostridium spp. in both examined species. E. coli and K. oxytoca were observed in Helix aspersa maxima and Helix aspersa muller. Furthermore, one case of fungi positivity in samples of Helix aspersa muller was found. The reported investigations highlight the need to create and adopt a reference legislation to protect the health of consumers. PMID:27800385

  12. Characterization of homoionic Fe{sup 2+}-type montmorillonite: Potential chemical species of iron contaminant

    SciTech Connect

    Kozai, Naofumi Inada, Koichi; Adachi, Yoshifusa; Kawamura, Sachi; Kashimoto, Yusuke; Kozaki, Tamotsu; Sato, Seichi; Ohnuki, Toshihiko; Sakai, Takuro; Sato, Takahiro; Oikawa, Masakazu; Esaka, Fumitaka; Mitamura, Hisayoshi

    2007-08-15

    Fe{sup 2+}-montmorillonite with Fe{sup 2+} ions occupying cation exchange sites is an ideal transformation product in bentonite buffer material. In our previous study on preparation and characterization of Fe{sup 2+}-montmorillonite, the montmorillonite sample that adsorbed Fe{sup 2+} ions on almost all of the cation exchange sites was prepared using a FeCl{sub 2} solution under an inert gas condition [N. Kozai, Y. Adachi, S. Kawamura, K. Inada, T. Kozaki, S. Sato, H. Ohashi, T. Ohnuki, T. Banba, J. Nucl. Sci. Technol. 38 (2001) 1141]. In view of the unstable nature of iron(II) chemical species, this study attempted to determine the potential contaminant iron chemical species in the sample. Nondestructive elemental analysis revealed that a small amount of chloride ions remained dispersed throughout the clay particles. The chloride ion retention may be due to the adsorption of FeCl{sup +} ion pairs in the initial FeCl{sub 2} solution and the subsequent containment of the Cl{sup -} ions that are dissociated from the FeCl{sup +} ion pairs during excess salt removal treatment. Two explanations are advanced for the second process: the slow release of the remaining Cl{sup -} ions from the collapsed interlayer of the montmorillonite, and the transformation of a minor fraction of the remaining FeCl{sup +} ion pairs to iron(III) hydroxide chloride complexes having low solubility. - Graphical abstract: The distribution of Si (left) and Cl (right) in homoionic Fe{sup 2+}-type montmorillonite prepared under an inert gas atmosphere by a conventional method using a FeCl{sub 2} solution. A small fraction of chloride ions remained dispersed throughout the clay. This paper mainly discusses the potential contaminant iron chemical species in this sample other than Fe{sup 2+} ions.

  13. Development of an automated chemical analysis system

    SciTech Connect

    Bennett, D.W.; Dodson, M.G.; Schur, A.; McGrail, B.P.; Shorpik, J.R. ); Barich, J.J. )

    1990-11-01

    Industrial robots, enhanced with an improved user interface, have been successfully implemented to improve productivity while minimizing worker exposure during chemical analysis of hazardous waste samples. The most significant advantage of the automated system may be the capability of monitoring and recording the steps in a procedure in real time for quality control purposes. This report briefly describes the use of a high-reliability, selectively complaint assembly robot arm used to implement EPA test method 3050. Results from the chemical analysis were compared with results from an EPA certified lab and inter-laboratory round robin. 4 refs.

  14. Integrated analysis of the Plasmodium species transcriptome.

    PubMed

    Hoo, Regina; Zhu, Lei; Amaladoss, Anburaj; Mok, Sachel; Natalang, Onguma; Lapp, Stacey A; Hu, Guangan; Liew, Kingsley; Galinski, Mary R; Bozdech, Zbynek; Preiser, Peter R

    2016-05-01

    The genome sequence available for different Plasmodium species is a valuable resource for understanding malaria parasite biology. However, comparative genomics on its own cannot fully explain all the species-specific differences which suggests that other genomic aspects such as regulation of gene expression play an important role in defining species-specific characteristics. Here, we developed a comprehensive approach to measure transcriptional changes of the evolutionary conserved syntenic orthologs during the intraerythrocytic developmental cycle across six Plasmodium species. We show significant transcriptional constraint at the mid-developmental stage of Plasmodium species while the earliest stages of parasite development display the greatest transcriptional variation associated with critical functional processes. Modeling of the evolutionary relationship based on changes in transcriptional profile reveal a phylogeny pattern of the Plasmodium species that strictly follows its mammalian hosts. In addition, the work shows that transcriptional conserved orthologs represent potential future targets for anti-malaria intervention as they would be expected to carry out key essential functions within the parasites. This work provides an integrated analysis of orthologous transcriptome, which aims to provide insights into the Plasmodium evolution thereby establishing a framework to explore complex pathways and drug discovery in Plasmodium species with broad host range. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  15. Penicillium arizonense, a new, genome sequenced fungal species, reveals a high chemical diversity in secreted metabolites

    PubMed Central

    Grijseels, Sietske; Nielsen, Jens Christian; Randelovic, Milica; Nielsen, Jens; Nielsen, Kristian Fog; Workman, Mhairi; Frisvad, Jens Christian

    2016-01-01

    A new soil-borne species belonging to the Penicillium section Canescentia is described, Penicillium arizonense sp. nov. (type strain CBS 141311T = IBT 12289T). The genome was sequenced and assembled into 33.7 Mb containing 12,502 predicted genes. A phylogenetic assessment based on marker genes confirmed the grouping of P. arizonense within section Canescentia. Compared to related species, P. arizonense proved to encode a high number of proteins involved in carbohydrate metabolism, in particular hemicellulases. Mining the genome for genes involved in secondary metabolite biosynthesis resulted in the identification of 62 putative biosynthetic gene clusters. Extracts of P. arizonense were analysed for secondary metabolites and austalides, pyripyropenes, tryptoquivalines, fumagillin, pseurotin A, curvulinic acid and xanthoepocin were detected. A comparative analysis against known pathways enabled the proposal of biosynthetic gene clusters in P. arizonense responsible for the synthesis of all detected compounds except curvulinic acid. The capacity to produce biomass degrading enzymes and the identification of a high chemical diversity in secreted bioactive secondary metabolites, offers a broad range of potential industrial applications for the new species P. arizonense. The description and availability of the genome sequence of P. arizonense, further provides the basis for biotechnological exploitation of this species. PMID:27739446

  16. Probabilistic Exposure Analysis for Chemical Risk Characterization

    PubMed Central

    Bogen, Kenneth T.; Cullen, Alison C.; Frey, H. Christopher; Price, Paul S.

    2009-01-01

    This paper summarizes the state of the science of probabilistic exposure assessment (PEA) as applied to chemical risk characterization. Current probabilistic risk analysis methods applied to PEA are reviewed. PEA within the context of risk-based decision making is discussed, including probabilistic treatment of related uncertainty, interindividual heterogeneity, and other sources of variability. Key examples of recent experience gained in assessing human exposures to chemicals in the environment, and other applications to chemical risk characterization and assessment, are presented. It is concluded that, although improvements continue to be made, existing methods suffice for effective application of PEA to support quantitative analyses of the risk of chemically induced toxicity that play an increasing role in key decision-making objectives involving health protection, triage, civil justice, and criminal justice. Different types of information required to apply PEA to these different decision contexts are identified, and specific PEA methods are highlighted that are best suited to exposure assessment in these separate contexts. PMID:19223660

  17. In-Situ Planetary Chemical Analysis

    NASA Technical Reports Server (NTRS)

    Kounaves, S. P.; Buehler, M. G.; Grannan, S. M.; Hecht, M. H.; Kuhlman, K. R.

    2000-01-01

    Both, the search for evidence of life on Mars and the assessment of the Martian environment in respect to its compatibility with human explorers, will require the ability to measure and understand the aqueous chemistry of the Martian regolith. Direct in-situ chemical analysis is the only method by which chemical biosignatures can be reliably recognized and the toxicity of the regolith accurately assessed. Qualitative and quantitative determination of the aqueous ionic constituents and their concentrations is critical in developing kinetic and thermodynamic models that can be used to accurately predict the potential of the past or present Martian geochemical environment to have either generated or still sustain life. In-situ chemical characterization could provide evidence as to whether the chemical composition of the regolith or evaporates in suspected ancient water bodies have been biologically influenced.

  18. In-Situ Planetary Chemical Analysis

    NASA Technical Reports Server (NTRS)

    Kounaves, S. P.; Buehler, M. G.; Grannan, S. M.; Hecht, M. H.; Kuhlman, K. R.

    2000-01-01

    Both, the search for evidence of life on Mars and the assessment of the Martian environment in respect to its compatibility with human explorers, will require the ability to measure and understand the aqueous chemistry of the Martian regolith. Direct in-situ chemical analysis is the only method by which chemical biosignatures can be reliably recognized and the toxicity of the regolith accurately assessed. Qualitative and quantitative determination of the aqueous ionic constituents and their concentrations is critical in developing kinetic and thermodynamic models that can be used to accurately predict the potential of the past or present Martian geochemical environment to have either generated or still sustain life. In-situ chemical characterization could provide evidence as to whether the chemical composition of the regolith or evaporates in suspected ancient water bodies have been biologically influenced.

  19. Chemical structure of wood charcoal by infrared spectroscopy and multivariate analysis

    Treesearch

    Nicole Labbe; David Harper; Timothy Rials; Thomas Elder

    2006-01-01

    In this work, the effect of temperature on charcoal structure and chemical composition is investigated for four tree species. Wood charcoal carbonized at various temperatures is analyzed by mid infrared spectroscopy coupled with multivariate analysis and by thermogravimetric analysis to characterize the chemical composition during the carbonization process. The...

  20. An extended chemical analysis of gallstone.

    PubMed

    Chandran, P; Kuchhal, N K; Garg, P; Pundir, C S

    2007-09-01

    Chemical composition of gall stones is essential for aetiopathogensis of gallstone disease. We have reported quantitative chemical analysis of total cholesterol bilirubin, calcium, iron and inorganic phosphate in 120 gallstones from haryana. To extend this chemical analysis of gall stones by studying more cases and by analyzing more chemical constituents. A quantitative chemical analysis of total cholesterol, total bilirubin, fatty acids, triglycerides, phospholipids, bile acids, soluble proteins, sodium potassium, magnesium, copper, oxalate and chlorides of biliary calculi (52 cholesterol, 76 mixed and 72 pigment) retrieved from surgical operation of 200 patients from Haryana state was carried out. Total cholesterol as the major component and total bilirubin, phospholipids, triglycerides, bile acids, fatty acids (esterified), soluble protein, calcium, magnesium, iron, copper, sodium, potassium, inorganic phosphate, oxalate and chloride as minor components were found in all types of calculi. The cholesterol stones had higher content of total cholesterol, phospholipids, fatty acids (esterified), inorganic phosphate and copper compared to mixed and pigment stones. The mixed stones had higher content of iron and triglycerides than to cholesterol and pigment stones. The pigment stones were richer in total bilirubin, bile acids, calcium, oxalate, magnesium, sodium, potassium, chloride and soluble protein compared to cholesterol and mixed stones. Although total cholesterol was a major component of cholesterol, mixed and pigment gall stone in Haryana, the content of most of the other lipids, cations and anions was different in different gall stones indicating their different mechanism of formation.

  1. Droplet microfluidics in (bio)chemical analysis.

    PubMed

    Basova, Evgenia Yu; Foret, Frantisek

    2015-01-07

    Droplet microfluidics may soon change the paradigm of performing chemical analyses and related instrumentation. It can improve not only the analysis scale, possibility for sensitivity improvement, and reduced consumption of chemical and biological reagents, but also the speed of performing a variety of unit operations. At present, microfluidic platforms can reproducibly generate monodisperse droplet populations at kHz or higher rates with droplet sizes suitable for high-throughput experiments, single-cell detection or even single molecule analysis. In addition to being used as microreactors with volume in the micro- to femtoliter range, droplet based systems have also been used to directly synthesize particles and encapsulate biological entities for biomedicine and biotechnology applications. This minireview summarizes various droplet microfluidics operations and applications for (bio)chemical assays described in the literature during the past few years.

  2. A hybrid computer program for rapidly solving flowing or static chemical kinetic problems involving many chemical species

    NASA Technical Reports Server (NTRS)

    Mclain, A. G.; Rao, C. S. R.

    1976-01-01

    A hybrid chemical kinetic computer program was assembled which provides a rapid solution to problems involving flowing or static, chemically reacting, gas mixtures. The computer program uses existing subroutines for problem setup, initialization, and preliminary calculations and incorporates a stiff ordinary differential equation solution technique. A number of check cases were recomputed with the hybrid program and the results were almost identical to those previously obtained. The computational time saving was demonstrated with a propane-oxygen-argon shock tube combustion problem involving 31 chemical species and 64 reactions. Information is presented to enable potential users to prepare an input data deck for the calculation of a problem.

  3. Chemical species of sulfur in prostate cancer cells studied by XANES spectroscopy

    NASA Astrophysics Data System (ADS)

    Czapla, Joanna; Kwiatek, Wojciech M.; Lekki, Janusz; Dulińska-Litewka, Joanna; Steininger, Ralph; Göttlicher, Jörg

    2013-12-01

    The role of sulfur in prostate cancer progression may be significant for understanding the process of carcinogenesis. This work, based on X-ray Absorption Near Edge Structure (XANES) spectroscopy, is focused on determination of sulfur chemical species occurring in prostate cancer cell lines. The experimental material consisted of four commercially available cell lines: three from metastasized prostate cancer (PC3, LNCaP, and DU145) and one, used as a control, from the non-tumourigenic peripheral zone of the prostate (PZ-HPV-7). The experiment was performed at the SUL-X beamline of the synchrotron radiation source ANKA, Karlsruhe (Germany). The K-edge XANES spectra of sulfur were analyzed by deconvolution in order to establish sulfur species that occur in prostate cancer cells and to find out whether there are any differences in their content between various cell lines. Experimental spectra were fitted in two ways: with two Gaussian peaks and one arctangent step function, and additionally by a Linear Combination Fit with spectra of reference compounds in order to obtain quantitative chemical information. All fitting procedures were performed with the Athena code (Ravel and Newville, 2005) and the results of deconvolution were used to determine the fraction of each sulfur form. The results of data analysis showed that cell lines from different metastasis had different ratio of reduced to oxidized sulfur species. The LCF analysis demonstrated that the highest content of GSH, one of the most important sulfur-bearing compounds in cells, was observed in DU145 cells. These findings may confirm the hypothesis of changes in redox balance in case of cancer initiation and progression.

  4. 40 CFR 761.253 - Chemical analysis.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Chemical analysis. 761.253 Section 761.253 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT... Sample Sites, Collecting Surface Samples, and Analyzing Standard PCB Wipe Samples § 761.253...

  5. 40 CFR 761.253 - Chemical analysis.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Chemical analysis. 761.253 Section 761.253 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT... Sample Sites, Collecting Surface Samples, and Analyzing Standard PCB Wipe Samples § 761.253...

  6. 40 CFR 761.253 - Chemical analysis.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Chemical analysis. 761.253 Section 761.253 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT... Sample Sites, Collecting Surface Samples, and Analyzing Standard PCB Wipe Samples § 761.253...

  7. 40 CFR 761.253 - Chemical analysis.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Chemical analysis. 761.253 Section 761.253 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT... Sample Sites, Collecting Surface Samples, and Analyzing Standard PCB Wipe Samples § 761.253...

  8. Wood Chemical Composition in Species of Cactaceae: The Relationship between Lignification and Stem Morphology

    PubMed Central

    Canché-Escamilla, Gonzalo; Soto-Hernández, Marcos

    2015-01-01

    In Cactaceae, wood anatomy is related to stem morphology in terms of the conferred support. In species of cacti with dimorphic wood, a unique process occurs in which the cambium stops producing wide-band tracheids (WBTs) and produces fibers; this is associated with the aging of individuals and increases in size. Stem support and lignification have only been studied in fibrous tree-like species, and studies in species with WBTs or dimorphic wood are lacking. In this study, we approach this process with a chemical focus, emphasizing the role of wood lignification. We hypothesized that the degree of wood lignification in Cactaceae increases with height of the species and that its chemical composition varies with wood anatomy. To test this, we studied the chemical composition (cellulose, hemicellulose, and lignin content) in 13 species (2 WBTs wood, 3 dimorphic, and 8 fibrous) with contrasting growth forms. We also analyzed lignification in dimorphic and fibrous species to determine the chemical features of WBTs and fibers and their relationship with stem support. The lignin contents were characterized by Fourier transform infrared spectroscopy and high performance liquid chromatography. We found that 11 species have a higher percentage (>35%) of lignin in their wood than other angiosperms or gymnosperms. The lignin chemical composition in fibrous species is similar to that of other dicots, but it is markedly heterogeneous in non-fibrous species where WBTs are abundant. The lignification in WBTs is associated with the resistance to high water pressure within cells rather than the contribution to mechanical support. Dimorphic wood species are usually richer in syringyl lignin, and tree-like species with lignified rays have more guaiacyl lignin. The results suggest that wood anatomy and lignin distribution play an important role in the chemical composition of wood, and further research is needed at the cellular level. PMID:25880223

  9. Wood chemical composition in species of Cactaceae: the relationship between lignification and stem morphology.

    PubMed

    Reyes-Rivera, Jorge; Canché-Escamilla, Gonzalo; Soto-Hernández, Marcos; Terrazas, Teresa

    2015-01-01

    In Cactaceae, wood anatomy is related to stem morphology in terms of the conferred support. In species of cacti with dimorphic wood, a unique process occurs in which the cambium stops producing wide-band tracheids (WBTs) and produces fibers; this is associated with the aging of individuals and increases in size. Stem support and lignification have only been studied in fibrous tree-like species, and studies in species with WBTs or dimorphic wood are lacking. In this study, we approach this process with a chemical focus, emphasizing the role of wood lignification. We hypothesized that the degree of wood lignification in Cactaceae increases with height of the species and that its chemical composition varies with wood anatomy. To test this, we studied the chemical composition (cellulose, hemicellulose, and lignin content) in 13 species (2 WBTs wood, 3 dimorphic, and 8 fibrous) with contrasting growth forms. We also analyzed lignification in dimorphic and fibrous species to determine the chemical features of WBTs and fibers and their relationship with stem support. The lignin contents were characterized by Fourier transform infrared spectroscopy and high performance liquid chromatography. We found that 11 species have a higher percentage (>35%) of lignin in their wood than other angiosperms or gymnosperms. The lignin chemical composition in fibrous species is similar to that of other dicots, but it is markedly heterogeneous in non-fibrous species where WBTs are abundant. The lignification in WBTs is associated with the resistance to high water pressure within cells rather than the contribution to mechanical support. Dimorphic wood species are usually richer in syringyl lignin, and tree-like species with lignified rays have more guaiacyl lignin. The results suggest that wood anatomy and lignin distribution play an important role in the chemical composition of wood, and further research is needed at the cellular level.

  10. Diffusion/Dispersion Transport of Chemically Reacting Species

    SciTech Connect

    Helgeson, Harold; Wenk, Hans-Rudolf

    2014-06-06

    The project characterized and quantified as a function of pressure, temperature and bulk composition the exergonic intra- and extracellular reactions catalyzed by thermo- and hyperthermophilic microbes at the oil-water interface in sedimentary basins. The reactions have been characterized and described quantitatively in terms of the chemical potentials of the components of the system in compositional hyperspace using thermodynamics, together with Gibbs free energy minimization and mass transfer computer experiments. A quantitative understanding of the biogeochemical processes responsible for the degradation of reservoired petroleum is fundamental to minimize the deleterious effects of microbial sulfidization and degradation processes.

  11. Mechanics of chemical species transport in the marine atmospheric boundary layer

    NASA Technical Reports Server (NTRS)

    Hanson, Howard P.

    1989-01-01

    Marine atmospheric boundary layer (MABL) drafts are modeled as steady-state plumes using the approach proposed by Telford (1966), and the model response to varying forcing and boundary conditions is examined. Since most of the chemical species are passive tracers within the MABL, variations in the implied fluxes are determined as a combination of the boundary conditions for the chemical species and the thermodynamic forcing implied by the stability and thermal boundary conditions.

  12. Chemical Demilitarization - Assembled Chemical Weapons Assessment (ACWA): Root Cause Analysis

    DTIC Science & Technology

    2011-07-01

    Anniston Army Depot in Alabama, Umatilla Chemical Depot in Oregon, and Deseret Chemical Depot in Utah. The chemical weapons in these facilities account...program office has allocated additional costs for closure based on data from the closure process at the Umatilla and Anniston Chemical Agent Disposal...contractor, PCAPP is approximately five times as complex than the Anniston incineration facility and BGCAPP is roughly ten times as complex.7 As an

  13. Microfabricated Gas Phase Chemical Analysis Systems

    SciTech Connect

    Casalnuovo, Stephen A.; Frye-Mason, Gregory C; Heller, Edwin J.; Hietala, Vincent M.; Kottenstette, Richard J.; Lewis, Patrick R.; Manginell, Ronald P.; Matzke, Carolyn M.; Wong, C. Channy

    1999-08-02

    A portable, autonomous, hand-held chemical laboratory ({mu}ChemLab{trademark}) is being developed for trace detection (ppb) of chemical warfare (CW) agents and explosives in real-world environments containing high concentrations of interfering compounds. Microfabrication is utilized to provide miniature, low-power components that are characterized by rapid, sensitive and selective response. Sensitivity and selectivity are enhanced using two parallel analysis channels, each containing the sequential connection of a front-end sample collector/concentrator, a gas chromatographic (GC) separator, and a surface acoustic wave (SAW) detector. Component design and fabrication and system performance are described.

  14. Molecular Genetic Analysis of Chlamydia Species.

    PubMed

    Sixt, Barbara S; Valdivia, Raphael H

    2016-09-08

    Species of Chlamydia are the etiologic agent of endemic blinding trachoma, the leading cause of bacterial sexually transmitted diseases, significant respiratory pathogens, and a zoonotic threat. Their dependence on an intracellular growth niche and their peculiar developmental cycle are major challenges to elucidating their biology and virulence traits. The last decade has seen tremendous advances in our ability to perform a molecular genetic analysis of Chlamydia species. Major achievements include the generation of large collections of mutant strains, now available for forward- and reverse-genetic applications, and the introduction of a system for plasmid-based transformation enabling complementation of mutations; expression of foreign, modified, or reporter genes; and even targeted gene disruptions. This review summarizes the current status of the molecular genetic toolbox for Chlamydia species and highlights new insights into their biology and new challenges in the nascent field of Chlamydia genetics.

  15. Phylogenetic signal in phenotypic traits related to carbon source assimilation and chemical sensitivity in Acinetobacter species.

    PubMed

    Van Assche, Ado; Álvarez-Pérez, Sergio; de Breij, Anna; De Brabanter, Joseph; Willems, Kris A; Dijkshoorn, Lenie; Lievens, Bart

    2017-01-01

    A common belief is that the phylogeny of bacteria may reflect molecular functions and phenotypic characteristics, pointing towards phylogenetic conservatism of traits. Here, we tested this hypothesis for a large set of Acinetobacter strains. Members of the genus Acinetobacter are widespread in nature, demonstrate a high metabolic diversity and are resistant to several environmental stressors. Notably, some species are known to cause opportunistic human infections. A total of 133 strains belonging to 33 species with validly published names, two genomic species and species of an as-yet unknown taxonomic status were analyzed using the GENIII technology of Biolog, which allows high-throughput phenotyping. We estimated the strength and significance of the phylogenetic signal of each trait across phylogenetic reconstructions based on partial RNA polymerase subunit B (rpoB) and core genome sequences. Secondly, we tested whether phylogenetic distance was a good predictor of trait differentiation by Mantel test analysis. And finally, evolutionary model fitting was used to determine if the data for each phenotypic character was consistent with a phylogenetic or an essentially random model of trait distribution. Our data revealed that some key phenotypic traits related to substrate assimilation and chemical sensitivity are linked to the phylogenetic placement of Acinetobacter species. The strongest phylogenetic signals found were for utilization of different carbon sources such as some organic acids, amino acids and sugars, thus suggesting that in the diversification of Acinetobacter carbon source assimilation has had a relevant role. Future work should be aimed to clarify how such traits have shaped the remarkable ability of this bacterial group to dominate in a wide variety of habitats.

  16. The electrochemical generation of useful chemical species from lunar materials

    NASA Technical Reports Server (NTRS)

    Tsai, Kan J.; Kuchynka, Daniel J.; Sammells, Anthony F.

    1990-01-01

    Electrochemical cells have been fabricated for the simultaneous generation of oxygen and lithium from a Li2O-containing molten salt (Li2O-LiCl-LiF). The cell utilizes an oxygen vacancy conducting solid electrolyte, yttria-stabilized zirconia (YSZ), to effect separation between oxygen evolving and lithium reduction half-cell reactions. The cell, which operates at 700-850 C, possesses rapid electrode kinetics at the lithium-alloy electrode with exchange current density values being greater than 60 mA/sq cm. When used in the electrolytic mode, lithium produced at the negative electrode would be continuously removed from the cell for later use (under lunar conditions) as an easily storable reducing agent for the chemical refining of lunar ores. Because of the high reversibility of this electrochemical system, it has also formed the basis for the lithium-oxygen secondary battery system which possesses the highest theoretical energy density yet investigated.

  17. The electrochemical generation of useful chemical species from lunar materials

    NASA Technical Reports Server (NTRS)

    Tsai, Kan J.; Kuchynka, Daniel J.; Sammells, Anthony F.

    1989-01-01

    The current status of work on an electrochemical technology for the simultaneous generation of oxygen and lithium from a Li2O containing molten salt (Li2O-LiCl-LiF) is discussed. The electrochemical cell utilizes an oxygen vacancy conducting solid electrolyte, yttria-stabilized zirconia, to effect separation between the oxygen evolving and lithium reduction half-cell reactions. The cell, which operates at 700 to 800 C, possesses rapid electrode kinetics at the lithium-alloy electrode with exchange current density values being greater than 60 mA/sq cm, showing high reversibility for this reaction. When used in the electrolytic mode, lithium produced at the negative electrode would be continuously removed from the cell for later use (under lunar conditions) as an easily storable reducting agent (compared to H2) for the chemical refining of lunar ores via the general reaction: 2Li + MO yields Li2O + M where MO represents a lunar ore. Emphasis to this time has been on the simulated lunar ore ilmenite (FeTiO3), which we have found becomes chemically reduced by Li at 432 C. Furthermore, both Fe2O3 and TiO2 have been reduced by Li to give the corresponding metal. This electrochemical approach provides a convenient route for producing metals under lunar conditions and oxygen for the continuous maintenance of human habitats on the Moon's surface. Because of the high reversibility of this electrochemical system, it has also formed the basis for the lithium-oxygen secondary battery. This secondary lithium-oxygen battery system posses the highest theoretical energy density yet investigated.

  18. Optofluidics in bio-chemical analysis

    NASA Astrophysics Data System (ADS)

    Guo, Yunbo; Fan, Xudong

    2012-01-01

    Optofluidics organically integrates microfluidics and photonics and is an emerging technology in biological and chemical analysis. In this paper, we overview the recent studies in bio-chemical sensing applications of optofluidics. Particularly, we report the research progress in our lab in developing diverse optofluidic devices using two unique configurations: thin-walled capillary based optofluidic ring resonator (OFRR) and multi-hole capillary based optofluidic platforms. The first one has been developed to be OFRR-based label-free biosensor, microfluidic laser based intra-cavity sensors, and on-column optical detectors for micro-gas chromatography (μGC), while the second one has been developed to be optofluidic Fabry-Pérot based label-free biosensor and optofluidic Surface-Enhanced Raman Spectroscopy (SERS) biosensor. All of these devices take advantage of superior fluidic handling capability and high sensitivity, and have been used in detecting various biological and chemical analytes in either liquid or vapor phase.

  19. Electron spectroscopy for chemical analysis: Sample analysis

    NASA Technical Reports Server (NTRS)

    Carter, W. B.

    1989-01-01

    Exposure conditions in atomic oxygen (ESCA) was performed on an SSL-100/206 Small Spot Spectrometer. All data were taken with the use of a low voltage electron flood gun and a charge neutralization screen to minimize charging effects on the data. The X-ray spot size and electron flood gun voltage used are recorded on the individual spectra as are the instrumental resolutions. Two types of spectra were obtained for each specimen: (1) general surveys, and (2) high resolution spectra. The two types of data reduction performed are: (1) semiquantitative compositional analysis, and (2) peak fitting. The materials analyzed are: (1) kapton 4, 5, and 6, (2) HDPE 19, 20, and 21, and (3) PVDF 4, 5, and 6.

  20. Structural and Chemical Characterization of Hardwood from Tree Species with Applications as Bioenergy Feedstocks

    PubMed Central

    Çetinkol, Özgül Persil; Smith-Moritz, Andreia M.; Cheng, Gang; Lao, Jeemeng; George, Anthe; Hong, Kunlun; Henry, Robert; Simmons, Blake A.; Heazlewood, Joshua L.; Holmes, Bradley M.

    2012-01-01

    Eucalypt species are a group of flowering trees widely used in pulp production for paper manufacture. For several decades, the wood pulp industry has focused research and development efforts on improving yields, growth rates and pulp quality through breeding and the genetic improvement of key tree species. Recently, this focus has shifted from the production of high quality pulps to the investigation of the use of eucalypts as feedstocks for biofuel production. Here the structure and chemical composition of the heartwood and sapwood of Eucalyptus dunnii, E. globulus, E. pillularis, E. urophylla, an E. urophylla-E. grandis cross, Corymbia citriodora ssp. variegata, and Acacia mangium were compared using nuclear magnetic resonance spectroscopy (NMR), X-ray diffraction (XRD) and biochemical composition analysis. Some trends relating to these compositions were also identified by Fourier transform near infrared (FT-NIR) spectroscopy. These results will serve as a foundation for a more comprehensive database of wood properties that will help develop criteria for the selection of tree species for use as biorefinery feedstocks. PMID:23300786

  1. Structural and chemical characterization of hardwood from tree species with applications as bioenergy feedstocks.

    PubMed

    Cetinkol, Özgül Persil; Smith-Moritz, Andreia M; Cheng, Gang; Lao, Jeemeng; George, Anthe; Hong, Kunlun; Henry, Robert; Simmons, Blake A; Heazlewood, Joshua L; Holmes, Bradley M

    2012-01-01

    Eucalypt species are a group of flowering trees widely used in pulp production for paper manufacture. For several decades, the wood pulp industry has focused research and development efforts on improving yields, growth rates and pulp quality through breeding and the genetic improvement of key tree species. Recently, this focus has shifted from the production of high quality pulps to the investigation of the use of eucalypts as feedstocks for biofuel production. Here the structure and chemical composition of the heartwood and sapwood of Eucalyptus dunnii, E. globulus, E. pillularis, E. urophylla, an E. urophylla-E. grandis cross, Corymbia citriodora ssp. variegata, and Acacia mangium were compared using nuclear magnetic resonance spectroscopy (NMR), X-ray diffraction (XRD) and biochemical composition analysis. Some trends relating to these compositions were also identified by Fourier transform near infrared (FT-NIR) spectroscopy. These results will serve as a foundation for a more comprehensive database of wood properties that will help develop criteria for the selection of tree species for use as biorefinery feedstocks.

  2. Toward systems metabolic engineering of Aspergillus and Pichia species for the production of chemicals and biofuels.

    PubMed

    Caspeta, Luis; Nielsen, Jens

    2013-05-01

    Recently genome sequence data have become available for Aspergillus and Pichia species of industrial interest. This has stimulated the use of systems biology approaches for large-scale analysis of the molecular and metabolic responses of Aspergillus and Pichia under defined conditions, which has resulted in much new biological information. Case-specific contextualization of this information has been performed using comparative and functional genomic tools. Genomics data are also the basis for constructing genome-scale metabolic models, and these models have helped in the contextualization of knowledge on the fundamental biology of Aspergillus and Pichia species. Furthermore, with the availability of these models, the engineering of Aspergillus and Pichia is moving from traditional approaches, such as random mutagenesis, to a systems metabolic engineering approach. Here we review the recent trends in systems biology of Aspergillus and Pichia species, highlighting the relevance of these developments for systems metabolic engineering of these organisms for the production of hydrolytic enzymes, biofuels and chemicals from biomass. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Structural and Chemical Characterization of Hardwood from Tree Species with Applications as Bioenergy Feedstocks

    SciTech Connect

    Çetinkol, Özgül Persil; Smith-Moritz, Andreia M.; Cheng, Gang; Lao, Jeemeng; George, Anthe; Hong, Kunlun; Henry, Robert; Simmons, Blake A.; Heazlewood, Joshua L.; Holmes, Bradley M.; Zabotina, Olga A.

    2012-12-28

    Eucalypt species are a group of flowering trees widely used in pulp production for paper manufacture. For several decades, the wood pulp industry has focused research and development efforts on improving yields, growth rates and pulp quality through breeding and the genetic improvement of key tree species. Recently, this focus has shifted from the production of high quality pulps to the investigation of the use of eucalypts as feedstocks for biofuel production. Here the structure and chemical composition of the heartwood and sapwood of Eucalyptus dunnii, E. globulus, E. pillularis, E. urophylla, an E. urophylla-E. grandis cross, Corymbia citriodora ssp. variegata, and Acacia mangium were compared using nuclear magnetic resonance spectroscopy (NMR), X-ray diffraction (XRD) and biochemical composition analysis. Some trends relating to these compositions were also identified by Fourier transform near infrared (FT-NIR) spectroscopy. These results will serve as a foundation for a more comprehensive database of wood properties that will help develop criteria for the selection of tree species for use as biorefinery feedstocks.

  4. Chemical and genetic characterization of Phlomis species and wild hybrids in Crete.

    PubMed

    Georgescu, Luciana; Stefanakis, Michalis K; Kokkini, Stella; Katerinopoulos, Haralambos E; Pirintsos, Stergios A

    2016-02-01

    The genus Phlomis is represented in the island of Crete (Greece, Eastern Mediterranean) by three species Phlomis cretica C. Presl., Phlomis fruticosa L., the island endemic Phlomis lanata Willd. and three hybrids Phlomis x cytherea Rech.f. (P. cretica x P. fruticosa), Phlomis x commixta Rech.f. (P. cretica x P. lanata) and Phlomis x sieberi Vierh. (P. fruticosa x P. lanata). This work describes (a) the profile of hybrids and parental species concerning their volatile compounds, (b) the suitability of ribosomal nuclear (ITS region), chloroplast (trnH-psbA), and AFLP markers to identify hybrids and (c) their competence to characterize the different chemotypes of both hybrids and their parental species. The cluster analysis and PCA constructed from chemical data (volatile oils) suggest that there are three groups of taxa. Group IA includes P. cretica and P. fruticosa, group IB includes P. x cytherea, whereas group II consists of P. x commixta, P. x sieberi and P. lanata. Volatile compounds detected only in the hybrids P. x sieberi and P. x commixta correspond to the 3% of the total compounds, value that is much higher in P. x cytherea (21%). Neighbor-joining, statistical parsimony analysis and the observations drawn from ribotypes spectrum of ITS markers divided Phlomis species in two groups, P. lanata and the complex P. cretica/P. fruticosa. In contrast to the ITS region, the plastid DNA marker follows a geographically related pattern. Neighbor-Net, PCA and Bayesian assignment analysis performed for AFLP markers separated the genotypes into three groups corresponding to populations of P. cretica, P. fruticosa, and P. lanata, respectively, while populations of P. x commixta, P. x cytherea, and P. x sieberi presented admixed ancestry. Most of the P. x cytherea samples were identified as F1 hybrids by Bayesian assignment test, while those of P. x commixta and P. x sieberi were identified as F2 hybrids. Overall, high chemical differentiation is revealed in one of the

  5. Size and chemical characterization of individual particles resulting from biomass burning of local southern California species

    Treesearch

    Philip J. Silva; Don-Yuan Liu; Christopher A. Noble; Kimberly A. Prather

    1999-01-01

    The chemical composition and size of individual particles derived from combustion products of several species found in Southern California were obtained using aerosol time-of-flight mass spectrometry. The major inorganic species observed in >90% of all biomass burning particles is potassium, indicated by the atomic ion, as well as clusters containing chloride,...

  6. Cross-species extrapolation of chemical effects: Challenges and new insights

    EPA Science Inventory

    One of the greatest uncertainties in chemical risk assessment is extrapolation of effects from tested to untested species. While this undoubtedly is a challenge in the human health arena, species extrapolation is a particularly daunting task in ecological assessments, where it is...

  7. Chemical Analysis of NOx Removal Under Different Reduced Electric Fields

    NASA Astrophysics Data System (ADS)

    Haddouche, A.; Lemerini, M.

    2015-07-01

    This work presents a chemical kinetic analysis of different species involved in nitrogen-oxygen mixed gas induced by stationary corona discharge at room temperature and atmospheric pressure. This study takes into account twenty different chemical species participating in one hundred and seventy selected chemical reactions. The reaction rate coefficients are taken from the literature, and the density is analyzed by the continuity equation without the diffusion term. A large number of investigations considered the removal of NOx showing the effects of N, O and O3 radicals. The aim of the present simulation is to complete these studies by analysing various plasma species under different reduced electric fields in the range of 100-200 Td (1 Td=10-21 V·m2). In particular, we analyze the time evolution of depopulation (10-9-10-3 s) of NOx. We have found that the depopulation rate of NO and NO2 is substantially affected by the rise of reduced electric field as it grows from 100 Td to 200 Td. This allows us to ascertain the important role played by the reduced electric field.

  8. Thermodynamic analysis of alternate energy carriers, hydrogen and chemical heat pipes

    NASA Technical Reports Server (NTRS)

    Cox, K. E.; Carty, R. H.; Conger, W. L.; Soliman, M. A.; Funk, J. E.

    1976-01-01

    Hydrogen and chemical heat pipes were proposed as methods of transporting energy from a primary energy source (nuclear, solar) to the user. In the chemical heat pipe system, primary energy is transformed into the energy of a reversible chemical reaction; the chemical species are then transmitted or stored until the energy is required. Analysis of thermochemical hydrogen schemes and chemical heat pipe systems on a second law efficiency or available work basis show that hydrogen is superior especially if the end use of the chemical heat pipe is electrical power.

  9. Chemical equilibria studies using multivariate analysis methods.

    PubMed

    Jaumot, Joaquim; Eritja, Ramon; Gargallo, Raimundo

    2011-02-01

    Chemical multiequilibria systems can be monitored efficiently with the aid of spectroscopic techniques. Both hard- and soft-modeling are effective and powerful tools to extract chemical information from spectroscopic data. Recently, hybrid approaches that combine the flexibility of soft-modeling with the precise solutions provided by hard-modeling have been proposed. Here, we tested the performance of these three chemometric approaches for the analysis of several simulated data sets. In addition, experimental data recorded during the study of the acid-base equilibria of two DNA structures (G-quadruplex and i-motif) corresponding to two short sequences of the k-ras oncogene were studied. Finally, we also analyzed the interaction of the two DNA sequences with the model ligand TMPyP4. The results obtained from the analysis of these data sets may be useful to determine the most appropriate use of each approach. Whenever the presence of optically active interferences or unknown drifts can be neglected and a chemical model can easily be proposed and fitted, the hard-modeling method shows the best performance. If any of these conditions is not fulfilled, a hybrid-modeling approach may be a better option because all the contributions (chemical and unknown) can be modeled and the ambiguities inherent to soft-modeling methods show minor effects.

  10. Electron Spectroscopy: Applications for Chemical Analysis

    NASA Astrophysics Data System (ADS)

    Hercules, David M.

    2004-12-01

    The development of X-ray photoelectron spectroscopy (ESCA, XPS) is reviewed from an historical perspective that is relevant to its use for analytical chemistry. The emphasis is on early development of the technique, primarily during the period, 1964 1977. During these years there were significant developments in instrumentation, accompanied by significant advances in understanding the fundamentals of the technique. First, a historical perspective is presented to establish the backdrop against which XPS was developed. The early work in the field dealt mainly with measuring and understanding chemical shifts for elements and particularly for organic compounds. This was an exciting time because XPS appeared to provide chemical information unavailable otherwise. A detailed summary of some of the early work on chemical shifts is presented. It was also established that XPS could be used for quantitative analysis of elements, compounds, and different oxidation states of the same element. As the development of XPS occurred, emphasis changed from measuring chemical shifts to developing XPS as a surface analytical tool, a role that it fills today. Early applications to the analysis of catalysts and polymers, use to study adsorption and surface reactions, application of XPS to electrochemistry and corrosion, and studies of atmospheric particulates are all reviewed.

  11. Chemical composition of the essential oil from Croton kimosorum, an endemic species to Madagascar.

    PubMed

    Rabehaja, Delphin J R; Ihandriharison, Harilala; Ramanoelina, Panja A R; Benja, Rakotonirina; Ratsimamanga-Urverg, Suzanne; Bighelli, Ange; Casanova, Joseph; Tomi, Félix

    2014-01-01

    Croton kimosorum Leandri is an endemic species to Madagascar. The chemical composition of aerial parts, leaf and stem oils is reported for the first time. Analysis was carried out by combination of chromatographic (CC, GC), spectroscopic and spectrometric (MS, 13C NMR) techniques. In total, 76 compounds have been identified. Essential oil isolated from aerial parts contained mainly linalool (21.6%), sabinene (10.4%), 1,8-cineole (6.3%), beta-pinene (6.2%), (E)-beta-caryophyllene (5.9%), terpinen-4-ol (4.8%), geraniol (4,5%) and germacrene D (2.3%). In comparison with the first sample, the composition of leaf and stem oils varied slightly, while essential oil isolated by vapor distillation from a semi-industrial still exhibited similar composition.

  12. On the stabilizing role of species diffusion in chemical enhanced oil recovery

    NASA Astrophysics Data System (ADS)

    Daripa, Prabir; Gin, Craig

    2015-11-01

    In this talk, the speaker will discuss a problem on the stability analysis related to the effect of species diffusion on stabilization of fingering in a Hele-Shaw model of chemical enhanced oil recovery. The formulation of the problem is motivated by a specific design principle of the immiscible interfaces in the hope that this will lead to significant stabilization of interfacial instabilities, there by improving oil recovery in the context of porous media flow. Testing the merits of this hypothesis poses some challenges which will be discussed along with some numerical results based on current formulation of this problem. Several open problems in this context will be discussed. This work is currently under progress. Supported by the grant NPRP 08-777-1-141 from the Qatar National Research Fund (a member of The Qatar Foundation).

  13. The electrochemical generation of useful chemical species from lunar materials

    NASA Technical Reports Server (NTRS)

    Tsai, Kan J.; Kuchynka, Daniel J.; Sammells, Anthony F.

    1989-01-01

    Electrochemical cells have been fabricated for the simultaneous generation of oxygen and lithium from a Li2O containing molten salt (Li2O-LiCl-LiF). The cell utilizes an oxygen vacancy conducting solid electrolyte, yttria-stabilized zirconia (YSZ), to effect separation between oxygen evolving and lithium reduction half-cell reactions. The cell, which operates at 700 to 850 C, possesses rapid electrode kinetics at the lithium-alloy electrode with exchange current density (i sub o) values being greater than 60mA sq cm. When used in the electrolytic mode, lithium produced at the negative electrode would be continuously removed from the cell for later use (under lunar conditions) as an easily storable reducing agent (compared to H2) for the chemical refining of lunar ores. Because of the high reversibility of this electrochemical system, it has also formed tha basis for the lithium oxygen secondary battery system which possesses the highest theoretical energy density yet investigated.

  14. Quantifying chemical reactions by using mixing analysis.

    PubMed

    Jurado, Anna; Vázquez-Suñé, Enric; Carrera, Jesús; Tubau, Isabel; Pujades, Estanislao

    2015-01-01

    This work is motivated by a sound understanding of the chemical processes that affect the organic pollutants in an urban aquifer. We propose an approach to quantify such processes using mixing calculations. The methodology consists of the following steps: (1) identification of the recharge sources (end-members) and selection of the species (conservative and non-conservative) to be used, (2) identification of the chemical processes and (3) evaluation of mixing ratios including the chemical processes. This methodology has been applied in the Besòs River Delta (NE Barcelona, Spain), where the River Besòs is the main aquifer recharge source. A total number of 51 groundwater samples were collected from July 2007 to May 2010 during four field campaigns. Three river end-members were necessary to explain the temporal variability of the River Besòs: one river end-member is from the wet periods (W1) and two are from dry periods (D1 and D2). This methodology has proved to be useful not only to compute the mixing ratios but also to quantify processes such as calcite and magnesite dissolution, aerobic respiration and denitrification undergone at each observation point.

  15. Optofluidic Microsystems for Chemical and Biological Analysis

    PubMed Central

    Fan, Xudong; White, Ian M.

    2011-01-01

    Optofluidics – the synergistic integration of photonics and microfluidics – has recently emerged as a new analytical field that provides a number of unique characteristics for enhanced sensing performance and simplification of microsystems. In this review, we describe various optofluidic architectures developed in the past five years, emphasize the mechanisms by which optofluidics enhances bio/chemical analysis capabilities, including sensing and the precise control of biological micro/nanoparticles, and envision new research directions to which optofluidics leads. PMID:22059090

  16. Chemical similarity and local community assembly in the species rich tropical genus Piper.

    PubMed

    Salazar, Diego; Jaramillo, M Alejandra; Marquis, Robert J

    2016-11-01

    Community ecologists have strived to find mechanisms that mediate the assembly of natural communities. Recent evidence suggests that natural enemies could play an important role in the assembly of hyper-diverse tropical plant systems. Classic ecological theory predicts that in order for coexistence to occur, species differences must be maximized across biologically important niche dimensions. For plant-herbivore interactions, it has been recently suggested that, within a particular community, plant species that maximize the difference in chemical defense profiles compared to neighboring taxa will have a relative competitive advantage. Here we tested the hypothesis that plant chemical diversity can affect local community composition in the hyper-diverse genus Piper at a lowland wet forest location in Costa Rica. We first characterized the chemical composition of 27 of the most locally abundant species of Piper. We then tested whether species with different chemical compositions were more likely to coexist. Finally, we assessed the degree to which Piper phylogenetic relationships are related to differences in secondary chemical composition and community assembly. We found that, on average, co-occurring species were more likely to differ in chemical composition than expected by chance. Contrary to expectations, there was no phylogenetic signal for overall secondary chemical composition. In addition we found that species in local communities were, on average, more phylogenetically closely related than expected by chance, suggesting that functional traits other than those measured here also influence local assembly. We propose that selection by herbivores for divergent chemistries between closely related species facilitates the coexistence of a high diversity of congeneric taxa via apparent competition. © 2016 by the Ecological Society of America.

  17. Assessing contaminant sensitivity of endangered and threatened aquatic species: Part I. Acute toxicity of five chemicals

    USGS Publications Warehouse

    Dwyer, F.J.; Mayer, F.L.; Sappington, L.C.; Buckler, D.R.; Bridges, C.M.; Greer, I.E.; Hardesty, D.K.; Henke, C.E.; Ingersoll, C.G.; Kunz, J.L.; Whites, D.W.; Augspurger, T.; Mount, D.R.; Hattala, K.; Neuderfer, G.N.

    2005-01-01

    Assessment of contaminant impacts to federally identified endangered, threatened and candidate, and state-identified endangered species (collectively referred to as "listed" species) requires understanding of a species' sensitivities to particular chemicals. The most direct approach would be to determine the sensitivity of a listed species to a particular contaminant or perturbation. An indirect approach for aquatic species would be application of toxicity data obtained from standard test procedures and species commonly used in laboratory toxicity tests. Common test species (fathead minnow, Pimephales promelas; sheepshead minnow, Cyprinodon variegatus; and rainbow trout, Oncorhynchus mykiss) and 17 listed or closely related species were tested in acute 96-hour water exposures with five chemicals (carbaryl, copper, 4-nonylphenol, pentachlorophenol, and permethrin) representing a broad range of toxic modes of action. No single species was the most sensitive to all chemicals. For the three standard test species evaluated, the rainbow trout was more sensitive than either the fathead minnow or sheepshead minnow and was equal to or more sensitive than listed and related species 81% of the time. To estimate an LC50 for a listed species, a factor of 0.63 can be applied to the geometric mean LC50 of rainbow trout toxicity data, and more conservative factors can be determined using variance estimates (0.46 based on 1 SD of the mean and 0.33 based on 2 SD of the mean). Additionally, a low- or no-acute effect concentration can be estimated by multiplying the respective LC50 by a factor of approximately 0.56, which supports the United States Environmental Protection Agency approach of multiplying the final acute value by 0.5 (division by 2). When captive or locally abundant populations of listed fish are available, consideration should be given to direct testing. When direct toxicity testing cannot be performed, approaches for developing protective measures using common test

  18. Assessing contaminant sensitivity of endangered and threatened aquatic species: part I. Acute toxicity of five chemicals.

    PubMed

    Dwyer, F J; Mayer, F L; Sappington, L C; Buckler, D R; Bridges, C M; Greer, I E; Hardesty, D K; Henke, C E; Ingersoll, C G; Kunz, J L; Whites, D W; Augspurger, T; Mount, D R; Hattala, K; Neuderfer, G N

    2005-02-01

    Assessment of contaminant impacts to federally identified endangered, threatened and candidate, and state-identified endangered species (collectively referred to as "listed" species) requires understanding of a species' sensitivities to particular chemicals. The most direct approach would be to determine the sensitivity of a listed species to a particular contaminant or perturbation. An indirect approach for aquatic species would be application of toxicity data obtained from standard test procedures and species commonly used in laboratory toxicity tests. Common test species (fathead minnow, Pimephales promelas; sheepshead minnow, Cyprinodon variegatus; and rainbow trout, Oncorhynchus mykiss) and 17 listed or closely related species were tested in acute 96-hour water exposures with five chemicals (carbaryl, copper, 4-nonylphenol, pentachlorophenol, and permethrin) representing a broad range of toxic modes of action. No single species was the most sensitive to all chemicals. For the three standard test species evaluated, the rainbow trout was more sensitive than either the fathead minnow or sheepshead minnow and was equal to or more sensitive than listed and related species 81% of the time. To estimate an LC50 for a listed species, a factor of 0.63 can be applied to the geometric mean LC50 of rainbow trout toxicity data, and more conservative factors can be determined using variance estimates (0.46 based on 1 SD of the mean and 0.33 based on 2 SD of the mean). Additionally, a low- or no-acute effect concentration can be estimated by multiplying the respective LC50 by a factor of approximately 0.56, which supports the United States Environmental Protection Agency approach of multiplying the final acute value by 0.5 (division by 2). When captive or locally abundant populations of listed fish are available, consideration should be given to direct testing. When direct toxicity testing cannot be performed, approaches for developing protective measures using common test

  19. A kinetic and equilibrium analysis of silicon carbide chemical vapor deposition on monofilaments

    NASA Technical Reports Server (NTRS)

    Gokoglu, S. A.; Kuczmarski, M. A.

    1993-01-01

    Chemical kinetics of atmospheric pressure silicon carbide (SiC) chemical vapor deposition (CVD) from dilute silane and propane source gases in hydrogen is numerically analyzed in a cylindrical upflow reactor designed for CVD on monofilaments. The chemical composition of the SiC deposit is assessed both from the calculated total fluxes of carbon and silicon and from chemical equilibrium considerations for the prevailing temperatures and species concentrations at and along the filament surface. The effects of gas and surface chemistry on the evolution of major gas phase species are considered in the analysis.

  20. Stochastic analysis of Chemical Reaction Networks using Linear Noise Approximation.

    PubMed

    Cardelli, Luca; Kwiatkowska, Marta; Laurenti, Luca

    2016-11-01

    Stochastic evolution of Chemical Reactions Networks (CRNs) over time is usually analyzed through solving the Chemical Master Equation (CME) or performing extensive simulations. Analysing stochasticity is often needed, particularly when some molecules occur in low numbers. Unfortunately, both approaches become infeasible if the system is complex and/or it cannot be ensured that initial populations are small. We develop a probabilistic logic for CRNs that enables stochastic analysis of the evolution of populations of molecular species. We present an approximate model checking algorithm based on the Linear Noise Approximation (LNA) of the CME, whose computational complexity is independent of the population size of each species and polynomial in the number of different species. The algorithm requires the solution of first order polynomial differential equations. We prove that our approach is valid for any CRN close enough to the thermodynamical limit. However, we show on four case studies that it can still provide good approximation even for low molecule counts. Our approach enables rigorous analysis of CRNs that are not analyzable by solving the CME, but are far from the deterministic limit. Moreover, it can be used for a fast approximate stochastic characterization of a CRN.

  1. Stochastic Analysis of Chemical Reaction Networks Using Linear Noise Approximation.

    PubMed

    Cardelli, Luca; Kwiatkowska, Marta; Laurenti, Luca

    2016-10-28

    Stochastic evolution of Chemical Reactions Networks (CRNs) over time is usually analysed through solving the Chemical Master Equation (CME) or performing extensive simulations. Analysing stochasticity is often needed, particularly when some molecules occur in low numbers. Unfortunately, both approaches become infeasible if the system is complex and/or it cannot be ensured that initial populations are small. We develop a probabilistic logic for CRNs that enables stochastic analysis of the evolution of populations of molecular species. We present an approximate model checking algorithm based on the Linear Noise Approximation (LNA) of the CME, whose computational complexity is independent of the population size of each species and polynomial in the number of different species. The algorithm requires the solution of first order polynomial differential equations. We prove that our approach is valid for any CRN close enough to the thermodynamical limit. However, we show on four case studies that it can still provide good approximation even for low molecule counts. Our approach enables rigorous analysis of CRNs that are not analyzable by solving the CME, but are far from the deterministic limit. Moreover, it can be used for a fast approximate stochastic characterization of a CRN. Copyright © 2016. Published by Elsevier Ireland Ltd.

  2. Quantum Chemical Strain Analysis For Mechanochemical Processes.

    PubMed

    Stauch, Tim; Dreuw, Andreas

    2017-03-24

    The use of mechanical force to initiate a chemical reaction is an efficient alternative to the conventional sources of activation energy, i.e., heat, light, and electricity. Applications of mechanochemistry in academic and industrial laboratories are diverse, ranging from chemical syntheses in ball mills and ultrasound baths to direct activation of covalent bonds using an atomic force microscope. The vectorial nature of force is advantageous because specific covalent bonds can be preconditioned for rupture by selective stretching. However, the influence of mechanical force on single molecules is still not understood at a fundamental level, which limits the applicability of mechanochemistry. As a result, many chemists still resort to rules of thumb when it comes to conducting mechanochemical syntheses. In this Account, we show that comprehension of mechanochemistry at the molecular level can be tremendously advanced by quantum chemistry, in particular by using quantum chemical force analysis tools. One such tool is the JEDI (Judgement of Energy DIstribution) analysis, which provides a convenient approach to analyze the distribution of strain energy in a mechanically deformed molecule. Based on the harmonic approximation, the strain energy contribution is calculated for each bond length, bond angle and dihedral angle, thus providing a comprehensive picture of how force affects molecules. This Account examines the theoretical foundations of quantum chemical force analysis and provides a critical overview of the performance of the JEDI analysis in various mechanochemical applications. We explain in detail how this analysis tool is to be used to identify the "force-bearing scaffold" of a distorted molecule, which allows both the rationalization and the optimization of diverse mechanochemical processes. More precisely, we show that the inclusion of every bond, bending and torsion of a molecule allows a particularly insightful discussion of the distribution of mechanical

  3. Chemical composition and antioxidant activity of certain Morus species

    PubMed Central

    Imran, Mohammad; Khan, Hamayun; Shah, Mohibullah; Khan, Rasool; Khan, Faridullah

    2010-01-01

    In the present work, the fruits of four Morus species, namely Morus alba (white mulberry), Morus nigra (black mulberry), Morus laevigata (large white fruit), and Morus laevigata (large black fruit), were analyzed for proximate composition, essential minerals, and antioxidant potentials. For this purpose, the ripe fruits were collected from the northern regions of Pakistan. The major nutritional components (moisture, ash, lipids, proteins, fibres, carbohydrates, and total sugar) were found to be in the suitable range along with good computed energy. Total dry weight, pH, and titratable acidity (percent citric acid) were (17.60±1.94)–(21.97±2.34) mg/100 g, (3.20±0.07)–(4.78±0.15), and (0.84±0.40)%–(2.00±0.08)%, respectively. Low riboflavin (vitamin B2) and niacin (vitamin B3) contents were recorded in all the fruits, while ascorbic acid (vitamin C) was in the range from (15.20±1.25) to (17.03±1.71) mg/100 g fresh weight (FW). The mulberry fruits were rich with regard to the total phenol and alkaloid contents, having values of (880±7.20)–(1650±12.25) mg/100 g FW and (390±.22)–(660±5.25) mg/100 g FW, respectively. Sufficient quantities of essential macro-(K, Ca, Mg, and Na) and micro-(Fe, Zn, and Ni) elements were found in all the fruits. K was the predominant element with concentration ranging from (1270±9.36) to (1731±11.50) mg/100 g, while Ca, Na, and Mg contents were (440±3.21)–(576±7.37), (260±3.86)–(280±3.50), and (24±3.51)–(360±4.20) mg/100 g, respectivly. The decreasing order of micro-minerals was Fe>Zn>Ni. The radical scavenging activity of methanolic extract of fruits was concentration-dependent and showed a correlation with total phenolic constituents of the respective fruits. Based on the results obtained, mulberry fruits were found to serve as a potential source of food diet and natural antioxidants. PMID:21121077

  4. Updated Chemical Kinetics and Sensitivity Analysis Code

    NASA Technical Reports Server (NTRS)

    Radhakrishnan, Krishnan

    2005-01-01

    An updated version of the General Chemical Kinetics and Sensitivity Analysis (LSENS) computer code has become available. A prior version of LSENS was described in "Program Helps to Determine Chemical-Reaction Mechanisms" (LEW-15758), NASA Tech Briefs, Vol. 19, No. 5 (May 1995), page 66. To recapitulate: LSENS solves complex, homogeneous, gas-phase, chemical-kinetics problems (e.g., combustion of fuels) that are represented by sets of many coupled, nonlinear, first-order ordinary differential equations. LSENS has been designed for flexibility, convenience, and computational efficiency. The present version of LSENS incorporates mathematical models for (1) a static system; (2) steady, one-dimensional inviscid flow; (3) reaction behind an incident shock wave, including boundary layer correction; (4) a perfectly stirred reactor; and (5) a perfectly stirred reactor followed by a plug-flow reactor. In addition, LSENS can compute equilibrium properties for the following assigned states: enthalpy and pressure, temperature and pressure, internal energy and volume, and temperature and volume. For static and one-dimensional-flow problems, including those behind an incident shock wave and following a perfectly stirred reactor calculation, LSENS can compute sensitivity coefficients of dependent variables and their derivatives, with respect to the initial values of dependent variables and/or the rate-coefficient parameters of the chemical reactions.

  5. Using phylogenetic information and chemical properties to predict species tolerances to pesticides.

    PubMed

    Guénard, Guillaume; Carsten von der Ohe, Peter; Carlisle Walker, Steven; Lek, Sovan; Legendre, Pierre

    2014-08-22

    Direct estimation of species' tolerance to pesticides and other toxic organic substances is a combinatorial problem, because of the large number of species-substance pairs. We propose a statistical modelling approach to predict tolerances associated with untested species-substance pairs, by using models fitted to tested pairs. This approach is based on the phylogeny of species and physico-chemical descriptors of pesticides, with both kinds of information combined in a bilinear model. This bilinear modelling approach predicts tolerance in untested species-compound pairs based on the facts that closely related species often respond similarly to toxic compounds and that chemically similar compounds often have similar toxic effects. The three tolerance models (median lethal concentration after 96 h) used up to 25 aquatic animal species and up to nine pesticides (organochlorines, organophosphates and carbamates). Phylogeny was estimated using DNA sequences, while the pesticides were described by their mode of toxic action and their octanol-water partition coefficients. The models explained 77-84% of the among-species variation in tolerance (log10 LC50). In cross-validation, 84-87% of the predicted tolerances for individual species were within a factor of 10 of the observed values. The approach can also be used to model other species response to multivariate stress factors.

  6. Acute toxicity of eight oil spill response chemicals to temperate, boreal, and Arctic species.

    PubMed

    Hansen, Bjørn Henrik; Altin, Dag; Bonaunet, Kristin; Overjordet, Ida Beathe

    2014-01-01

    The objectives of this study were to (1) determine the acute toxicity of selected shoreline washing agents (SWA) and dispersants, and (2) assess interspecies differences in sensitivity to the products. Eight shoreline washing agents (Hela saneringsvæske, Bios, Bioversal, Absorrep K212, and Corexit 9580) and chemical dispersants (Corexit 9500, Dasic NS, and Gamlen OD4000) were tested on five marine species, algae Skeletonema costatum, planktonic copepod species Acartia tonsa (temperate species), Calanus finmarchicus (boreal species) and Calanus glacialis (Arctic species), and benthic amphipod Corophium volutator. For most products, A. tonsa was the most sensitive species, whereas C. volutator was the least sensitive; however, these species were exposed through different media (water/sediment). In general, all copepod species displayed a relatively similar sensitivity to all products. However, A. tonsa was somewhat more sensitive than other copepods to most of the tested products. Thus, A. tonsa appears to be a candidate species for boreal and Arctic copepods for acute toxicity testing, and data generated on this species may be used as to provide conservative estimates. The benthic species (C. volutator) had a different sensitivity pattern relative to pelagic species, displaying higher sensitivity to solvent-based SWA than to water-based SWA. Comparing product toxicity, the dispersants were in general most toxic while the solvent-based SWA were least toxic to pelagic species.

  7. Various chemical strategies to deceive ants in three Arhopala species (lepidoptera: Lycaenidae) exploiting Macaranga myrmecophytes.

    PubMed

    Inui, Yoko; Shimizu-Kaya, Usun; Okubo, Tadahiro; Yamsaki, Eri; Itioka, Takao

    2015-01-01

    Macaranga myrmecophytes (ant-plants) are generally well protected from herbivore attacks by their symbiotic ants (plant-ants). However, larvae of Arhopala (Lepidoptera: Lycaenidae) species survive and develop on specific Macaranga ant-plant species without being attacked by the plant-ants of their host species. We hypothesized that Arhopala larvae chemically mimic or camouflage themselves with the ants on their host plant so that the larvae are accepted by the plant-ant species of their host. Chemical analyses of cuticular hydrocarbons showed that chemical congruency varied among Arhopala species; A. dajagaka matched well the host plant-ants, A. amphimuta did not match, and unexpectedly, A. zylda lacked hydrocarbons. Behaviorally, the larvae and dummies coated with cuticular chemicals of A. dajagaka were well attended by the plant-ants, especially by those of the host. A. amphimuta was often attacked by all plant-ants except for the host plant-ants toward the larvae, and those of A. zylda were ignored by all plant-ants. Our results suggested that conspicuous variations exist in the chemical strategies used by the myrmecophilous butterflies that allow them to avoid ant attack and be accepted by the plant-ant colonies.

  8. Various Chemical Strategies to Deceive Ants in Three Arhopala Species (Lepidoptera: Lycaenidae) Exploiting Macaranga Myrmecophytes

    PubMed Central

    Inui, Yoko; Shimizu-kaya, Usun; Okubo, Tadahiro; Yamsaki, Eri; Itioka, Takao

    2015-01-01

    Macaranga myrmecophytes (ant-plants) are generally well protected from herbivore attacks by their symbiotic ants (plant-ants). However, larvae of Arhopala (Lepidoptera: Lycaenidae) species survive and develop on specific Macaranga ant-plant species without being attacked by the plant-ants of their host species. We hypothesized that Arhopala larvae chemically mimic or camouflage themselves with the ants on their host plant so that the larvae are accepted by the plant-ant species of their host. Chemical analyses of cuticular hydrocarbons showed that chemical congruency varied among Arhopala species; A. dajagaka matched well the host plant-ants, A. amphimuta did not match, and unexpectedly, A. zylda lacked hydrocarbons. Behaviorally, the larvae and dummies coated with cuticular chemicals of A. dajagaka were well attended by the plant-ants, especially by those of the host. A. amphimuta was often attacked by all plant-ants except for the host plant-ants toward the larvae, and those of A. zylda were ignored by all plant-ants. Our results suggested that conspicuous variations exist in the chemical strategies used by the myrmecophilous butterflies that allow them to avoid ant attack and be accepted by the plant-ant colonies. PMID:25853675

  9. Chemical, Bioactive, and Antioxidant Potential of Twenty Wild Culinary Mushroom Species.

    PubMed

    Sharma, S K; Gautam, N

    2015-01-01

    The chemical, bioactive, and antioxidant potential of twenty wild culinary mushroom species being consumed by the people of northern Himalayan regions has been evaluated for the first time in the present study. Nutrients analyzed include protein, crude fat, fibres, carbohydrates, and monosaccharides. Besides, preliminary study on the detection of toxic compounds was done on these species. Bioactive compounds evaluated are fatty acids, amino acids, tocopherol content, carotenoids (β-carotene, lycopene), flavonoids, ascorbic acid, and anthocyanidins. Fruitbodies extract of all the species was tested for different types of antioxidant assays. Although differences were observed in the net values of individual species all the species were found to be rich in protein, and carbohydrates and low in fat. Glucose was found to be the major monosaccharide. Predominance of UFA (65-70%) over SFA (30-35%) was observed in all the species with considerable amounts of other bioactive compounds. All the species showed higher effectiveness for antioxidant capacities.

  10. Chemical, Bioactive, and Antioxidant Potential of Twenty Wild Culinary Mushroom Species

    PubMed Central

    Sharma, S. K.; Gautam, N.

    2015-01-01

    The chemical, bioactive, and antioxidant potential of twenty wild culinary mushroom species being consumed by the people of northern Himalayan regions has been evaluated for the first time in the present study. Nutrients analyzed include protein, crude fat, fibres, carbohydrates, and monosaccharides. Besides, preliminary study on the detection of toxic compounds was done on these species. Bioactive compounds evaluated are fatty acids, amino acids, tocopherol content, carotenoids (β-carotene, lycopene), flavonoids, ascorbic acid, and anthocyanidins. Fruitbodies extract of all the species was tested for different types of antioxidant assays. Although differences were observed in the net values of individual species all the species were found to be rich in protein, and carbohydrates and low in fat. Glucose was found to be the major monosaccharide. Predominance of UFA (65–70%) over SFA (30–35%) was observed in all the species with considerable amounts of other bioactive compounds. All the species showed higher effectiveness for antioxidant capacities. PMID:26199938

  11. Analysis of Chemical Technology Division waste streams

    SciTech Connect

    Abraham, T.J.; Donaldson, T.L.; Walker, A.B.; Cummins, R.L.; Reeves, M.E.; Hylton, T.D.

    1990-07-01

    This document is a summary of the sources, quantities, and characteristics of the wastes generated by the Chemical Technology Division (CTD) of the Oak Ridge National Laboratory. The major contributors of hazardous, mixed, and radioactive wastes in the CTD as of the writing of this document were the Chemical Development Section, the Isotopes Section, and the Process Development Section. The objectives of this report are to identify the sources and the summarize the quantities and characteristics of hazardous, mixed, gaseous, and solid and liquid radioactive wastes that are generated by the Chemical Technology Division (CTD) of the Oak Ridge National Laboratory (ORNL). This study was performed in support of the CTD waste-reduction program -- the goals of which are to reduce both the volume and hazard level of the waste generated by the division. Prior to the initiation of any specific waste-reduction projects, an understanding of the overall waste-generation system of CTD must be developed. Therefore, the general approach taken in this study is that of an overall CTD waste-systems analysis, which is a detailed presentation of the generation points and general characteristics of each waste stream in CTD. The goal of this analysis is to identify the primary waste generators in the division and determine the most beneficial areas to initiate waste-reduction projects. 4 refs., 4 figs., 13 tabs.

  12. Identification of two-step chemical mechanisms using small temperature oscillations and a single tagged species

    NASA Astrophysics Data System (ADS)

    Closa, F.; Gosse, C.; Jullien, L.; Lemarchand, A.

    2015-05-01

    In order to identify two-step chemical mechanisms, we propose a method based on a small temperature modulation and on the analysis of the concentration oscillations of a single tagged species involved in the first step. The thermokinetic parameters of the first reaction step are first determined. Then, we build test functions that are constant only if the chemical system actually possesses some assumed two-step mechanism. Next, if the test functions plotted using experimental data are actually even, the mechanism is attributed and the obtained constant values provide the rate constants and enthalpy of reaction of the second step. The advantage of the protocol is to use the first step as a probe reaction to reveal the dynamics of the second step, which can hence be relieved of any tagging. The protocol is anticipated to apply to many mechanisms of biological relevance. As far as ligand binding is considered, our approach can address receptor conformational changes or dimerization as well as competition with or modulation by a second partner. The method can also be used to screen libraries of untagged compounds, relying on a tracer whose concentration can be spectroscopically monitored

  13. Glycoprotein emulsifiers from two marine Halomonas species: chemical and physical characterization.

    PubMed

    Gutiérrez, T; Mulloy, B; Black, K; Green, D H

    2007-11-01

    To partially purify and characterize bioemulsifiers produced by two new marine Halomonas species, TG39 and TG67, and to compare their emulsifying activities with those of commercial emulsifiers. The production of emulsifiers HE39 and HE67 was achieved from glucose-supplemented marine broth, and recovered by cell removal, concentration by ultrafiltration, precipitation with salt and ethanol, and lyophilization. Purification and chemical analysis revealed both emulsifiers to be glycoproteins of high molecular weight with a notably high content of protein and uronic acids. Physical characterization showed both glycoproteins to effectively emulsify a wide range of food oils under both neutral and acidic pH conditions and withstand acid and high temperature treatment. The emulsifying activities of these two new glycoprotein emulsifiers were comparable and, under certain conditions, superior to those produced by commercial emulsifiers tested (xanthan gum, gum arabic and lecithin). They show the highest reported emulsifying activities derived from a Halomonas species. These strains, and the emulsifiers produced, appear to be promising candidates for further development in applications requiring emulsifiers that are natural and compatible to the existing commercial emulsifiers.

  14. Evaluation of Chemical Composition and Antileishmanial and Antituberculosis Activities of Essential Oils of Piper Species.

    PubMed

    Bernuci, Karine Zanoli; Iwanaga, Camila Cristina; Fernadez-Andrade, Carla Maria Mariano; Lorenzetti, Fabiana Brusco; Torres-Santos, Eduardo Caio; Faiões, Viviane Dos Santos; Gonçalves, José Eduardo; do Amaral, Wanderlei; Deschamps, Cícero; Scodro, Regiane Bertin de Lima; Cardoso, Rosilene Fressatti; Baldin, Vanessa Pietrowski; Cortez, Diógenes Aparício Garcia

    2016-12-12

    Essential oils from fresh Piperaceae leaves were obtained by hydrodistillation and analyzed by gas chromatography mass spectrometry (GC-MS), and a total of 68 components were identified. Principal components analysis results showed a chemical variability between species, with sesquiterpene compounds predominating in the majority of species analyzed. The composition of the essential oil of Piper mosenii was described for the first time. The cytotoxicity of the essential oils was evaluated in peritoneal macrophages and the oils of P. rivinoides, P. arboretum, and P. aduncum exhibited the highest values, with cytotoxic concentration at 50% (CC50) > 200 µg/mL. Both P. diospyrifolium and P. aduncum displayed activity against Leishmania amazonensis, and were more selective for the parasite than for the macrophages, with a selectivity index (SI) of 2.35 and >5.52, respectively. These SI values were greater than the 1 for the standard drug pentamidine. The antileishmanial activity of the essential oils of P. diospyrifolium and P. aduncum was described for the first time. P. rivinoides, P. cernuum, and P. diospyrifolium displayed moderate activity against the Mycobacterium tuberculosis H37Rv bacillus, with a minimum inhibitory concentration (MIC) of 125 µg/mL. These results are relevant and suggests their potential for therapeutic purposes. Nevertheless, further studies are required to explain the exact mechanism of action of these essential oils.

  15. Experimental and Quantum-Chemical Study of Electronically Excited States of Protolytic Isovanillin Species

    NASA Astrophysics Data System (ADS)

    Vusovich, O. V.; Tchaikovskaya, O. N.; Sokolova, I. V.; Vasil'eva, N. Yu.

    2014-05-01

    Methods of electronic spectroscopy and quantum chemistry are used to compare protolytic vanillin and isovanillin species. Three protolytic species: anion, cation, and neutral are distinguished in the ground state of the examined molecules. Vanillin and isovanillin in the ground state in water possess identical spectral characteristics: line positions and intensities in the absorption spectra coincide. Minima of the electrostatic potential demonstrate that the deepest isomer minimum is observed on the carbonyl oxygen atom. However, investigations of the fluorescence spectra show that the radiative properties of isomers differ. An analysis of results of quantum-chemical calculations demonstrate that the long-wavelength ππ* transition in the vanillin absorption spectra is formed due to electron charge transfer from the phenol part of the molecule to oxygen atoms of the methoxy and carbonyl groups, and in the isovanillin absorption spectra, it is formed only on the oxygen atom of the methoxy group. The presence of hydroxyl and carbonyl groups in the structure of the examined molecules leads to the fact that isovanillin in the ground S0 state, the same as vanillin, possesses acidic properties, whereas in the excited S1 state, they possess basic properties. A comparison of the рKа values of aqueous solutions demonstrates that vanillin possesses stronger acidic and basic properties in comparison with isovanillin.

  16. Interim Report: CHEMICAL SPECIES OF MIGRATING RADIONUCLIDES AT COMMERCIAL SHALLOW LAND BURIAL SITES

    SciTech Connect

    Kirby, L. J.; Rickard, W. H.; Toste, A. P.

    1982-08-01

    This is the first quarterly report for .the project "Chemical Species of Migrating Radionuclides at Commercial Shallow Land Burial Site" under the new reporting schedule requested by the sponsor. Future reports will be issued following each fiscal quarter, with the next report scheduled in October, 1982. The primary purpose of this project is to develop an understanding of the processes responsible for radionuclide migration at low-level waste burial sites. Chemical measurements of waste trench leachate and identification of chemical changes in leachate during migration will provide a basis for geochemical waste transport models. This project will produce for the U.S. Nuclear Regulatory Commission information to support guidance for implementation of 10 CFR 61, particularly in the development of criteria for low level waste disposal site selection, management, permanent closure and monitoring. Topics covered include: Experimental Trench and Well Study; Chemical Species Characterization; Specific Radionuclide Mapping; Organic Complexing Compounds,

  17. VALIDATION GUIDELINES FOR LABORATORIES PERFORMING FORENSIC ANALYSIS OF CHEMICAL TERRORISM

    EPA Science Inventory

    The Scientific Working Group on Forensic Analysis of Chemical Terrorism (SWGFACT) has developed the following guidelines for laboratories engaged in the forensic analysis of chemical evidence associated with terrorism. This document provides a baseline framework and guidance for...

  18. VALIDATION GUIDELINES FOR LABORATORIES PERFORMING FORENSIC ANALYSIS OF CHEMICAL TERRORISM

    EPA Science Inventory

    The Scientific Working Group on Forensic Analysis of Chemical Terrorism (SWGFACT) has developed the following guidelines for laboratories engaged in the forensic analysis of chemical evidence associated with terrorism. This document provides a baseline framework and guidance for...

  19. Analysis of Plasmalogen Species in Foodstuffs.

    PubMed

    Yamashita, Shinji; Kanno, Susumu; Honjo, Ayako; Otoki, Yurika; Nakagawa, Kiyotaka; Kinoshita, Mikio; Miyazawa, Teruo

    2016-02-01

    Ethanolamine plasmalogen (PlsEtn), which is present at high levels in brains, is believed to be involved in neuronal protection. The present study was performed to search for PlsEtn resources in foodstuffs. The foodstuffs examined showed a wide range of PlsEtn contents from 5 to 549 μmol/100 g wet wt. The marine invertebrates, blue mussel, and ascidian had high PlsEtn contents (over 200 μmol/100 g wet wt). Profiling of the molecular species showed that the predominant fatty acids of PlsEtn species were 20:5 (EPA) and 22:6 (DHA) at the sn-2 position of the glycerol moiety in marine foodstuffs, whereas major PlsEtn species in land foodstuffs were 20:4. Following quantitative analysis by multiple reaction monitoring, the ascidian viscera were shown to contain the highest levels of 18:0/20:5-PlsEtn and 18:0/22:6-PlsEtn (86 and 68 μmol/100 g wet wt, respectively). In order to evaluate a neuronal antiapoptotic effect of these PlsEtn species, human neuroblastoma SH-SY5Y cells were treated with ethanolamine glycerophospholipid (EtnGpl), purified from the ascidian viscera, under serum starvation conditions. Extrinsic EtnGpl from ascidian viscera showed stronger suppression of cell death induced by serum starvation than with bovine brain EtnGpl. The EtnGpl from ascidian viscera strongly suppressed the activation of caspase 3. These results suggest that PlsEtn, especially that containing EPA and DHA, from marine foodstuffs is potentially useful for a therapeutic dietary supplement preventing neurodegenerative diseases, such as Alzheimer's disease (AD).

  20. Bacterial mixture analysis with Raman chemical imaging microspectroscopy

    NASA Astrophysics Data System (ADS)

    Tripathi, Ashish; Jabbour, Rabih E.; Guicheteau, Jason A.; Christesen, Steven D.; Emge, Darren K.; Jensen, Janet L.; Snyder, A. Peter

    2009-05-01

    Raman chemical imaging microspectroscopy (RCIM) is being evaluated as a technology for waterborne pathogen detection. Binary and ternary mixtures including combinations of polystyrene beads, Grampositive Bacillus anthracis and B. atrophaeus spores, B. cereus vegetative cells, and Gram-negative E. coli cells were investigated by RCIM for differentiation and characterization purposes. We have demonstrated the ability of RCIM, in combination with Pearson's cross correlation and multivariate principal components analysis data reduction techniques, to differentiate these components in the same field of view (FOV). Conventional applications of RCIM consist of differentiating relatively broad areas in a FOV. Here, RCIM is expanded in its capabilities to differentiate and distinguish between different micron size species in single particles and clusters of mixed species.

  1. Thermoanalytical, chemical and principal component analysis of plant drugs.

    PubMed

    Wesołowski, Marek; Konieczyński, Pawel

    2003-08-27

    Thermal decomposition and elemental content of commercial raw plant materials used in medicine-roots, rhizomes and bark originating from different medicinal plant species were analyzed. The thermal decomposition was performed using the derivatograph. The content of non-metallic (N, P, S, Cl, I and B) and metallic (Ca, Mg, Fe, Mn, Cu and Zn) elements was determined by spectrophotometric techniques after previous mineralization of samples. In order to obtain more clear classification of the analyzed plant materials principal component analysis (PCA) was applied. Interpretation of PCA results for three databases (thermoanalytical, non-metals and metals data sets) allows the statement that samples of roots, rhizomes and bark from the same plant species in majority of cases are characterized by similar elemental composition and similar course of their thermal decomposition. In this way the differences in general chemical composition of medicinal plants raw materials can be determined.

  2. Comparative human and rat neurospheres reveal species differences in chemical effects on neurodevelopmental key events.

    PubMed

    Baumann, Jenny; Gassmann, Kathrin; Masjosthusmann, Stefan; DeBoer, Denise; Bendt, Farina; Giersiefer, Susanne; Fritsche, Ellen

    2016-06-01

    The developing brain is highly vulnerable to the adverse effects of chemicals, resulting in neurodevelopmental disorders in humans. Currently, animal experiments in the rat are the gold standard for developmental neurotoxicity (DNT) testing; however, these guideline studies are insufficient in terms of animal use, time and costs and bear the issue of species extrapolation. Therefore, the necessity for alternative methods that predict DNT of chemicals faster, cheaper and with a high predictivity for humans is internationally agreed on. In this respect, we developed an in vitro model for DNT key event screening, which is based on primary human and rat neural progenitor cells grown as neurospheres. They are able to mimic basic processes of early fetal brain development and enable an investigation of species differences between humans and rodents in corresponding cellular models. The goal of this study was to investigate to what extent human and rat neurospheres were able to correctly predict the DNT potential of a well-characterized training set of nine chemicals by investigating effects on progenitor cell proliferation, migration and neuronal differentiation in parallel to cell viability, and to compare these chemical responses between human and rat neurospheres. We demonstrate that (1) by correlating these human and rat in vitro results to existing in vivo data, human and rat neurospheres classified most compounds correctly and thus may serve as a valuable component of a modular DNT testing strategy and (2) human and rat neurospheres differed in their sensitivity to most chemicals, reflecting toxicodynamic species differences of chemicals.

  3. Principal component analysis on chemical abundances spaces

    NASA Astrophysics Data System (ADS)

    Ting, Yuan-Sen; Freeman, Kenneth C.; Kobayashi, Chiaki; De Silva, Gayandhi M.; Bland-Hawthorn, Joss

    2012-04-01

    In preparation for the High Efficiency and Resolution Multi-Element Spectrograph (HERMES) chemical tagging survey of about a million Galactic FGK stars, we estimate the number of independent dimensions of the space defined by the stellar chemical element abundances [X/Fe]. This leads to a way to study the origin of elements from observed chemical abundances using principal component analysis. We explore abundances in several environments, including solar neighbourhood thin/thick disc stars, halo metal-poor stars, globular clusters, open clusters, the Large Magellanic Cloud and the Fornax dwarf spheroidal galaxy. By studying solar-neighbourhood stars, we confirm the universality of the r-process that tends to produce [neutron-capture elements/Fe] in a constant ratio. We find that, especially at low metallicity, the production of r-process elements is likely to be associated with the production of α-elements. This may support the core-collapse supernovae as the r-process site. We also verify the overabundances of light s-process elements at low metallicity, and find that the relative contribution decreases at higher metallicity, which suggests that this lighter elements primary process may be associated with massive stars. We also verify the contribution from the s-process in low-mass asymptotic giant branch (AGB) stars at high metallicity. Our analysis reveals two types of core-collapse supernovae: one produces mainly α-elements, the other produces both α-elements and Fe-peak elements with a large enhancement of heavy Fe-peak elements which may be the contribution from hypernovae. Excluding light elements that may be subject to internal mixing, K and Cu, we find that the [X/Fe] chemical abundance space in the solar neighbourhood has about six independent dimensions both at low metallicity (-3.5 ≲ [Fe/H] ≲-2) and high metallicity ([Fe/H] ≳-1). However the dimensions come from very different origins in these two cases. The extra contribution from low-mass AGB

  4. Predicting Toxicities of Diverse Chemical Pesticides in Multiple Avian Species Using Tree-Based QSAR Approaches for Regulatory Purposes.

    PubMed

    Basant, Nikita; Gupta, Shikha; Singh, Kunwar P

    2015-07-27

    A comprehensive safety evaluation of chemicals should require toxicity assessment in both the aquatic and terrestrial test species. Due to the application practices and nature of chemical pesticides, the avian toxicity testing is considered as an essential requirement in the risk assessment process. In this study, tree-based multispecies QSAR (quantitative-structure activity relationship) models were constructed for predicting the avian toxicity of pesticides using a set of nine descriptors derived directly from the chemical structures and following the OECD guidelines. Accordingly, the Bobwhite quail toxicity data was used to construct the QSAR models (SDT, DTF, DTB) and were externally validated using the toxicity data in four other test species (Mallard duck, Ring-necked pheasant, Japanese quail, House sparrow). Prior to the model development, the diversity in the chemical structures and end-point were verified. The external predictive power of the QSAR models was tested through rigorous validation deriving a wide series of statistical checks. Intercorrelation analysis and PCA methods provided information on the association of the molecular descriptors related to MW and topology. The S36 and MW were the most influential descriptors identified by DTF and DTB models. The DTF and DTB performed better than the SDT model and yielded a correlation (R(2)) of 0.945 and 0.966 between the measured and predicted toxicity values in test data array. Both these models also performed well in four other test species (R(2) > 0.918). ChemoTyper was used to identify the substructure alerts responsible for the avian toxicity. The results suggest for the appropriateness of the developed QSAR models to reliably predict the toxicity of pesticides in multiple avian test species and can be useful tools in screening the new chemical pesticides for regulatory purposes.

  5. Electrochemical approaches for chemical and biological analysis on Mars

    NASA Technical Reports Server (NTRS)

    Kounaves, Samuel P.

    2003-01-01

    Obtaining in situ chemical data from planetary bodies such as Mars or Europa can present significant challenges. The one analytical technique that has many of the requisite characteristics to meet such a challenge is electroanalysis. Described here are three electroanalytical devices designed for in situ geochemical and biological analysis on Mars. The Mars Environmental Compatibility Assessment (MECA) was built and flight qualified for the now cancelled NASA Mars 2001 Lander. Part of MECA consisted of four "cells" containing arrays of electrochemical based sensors for measuring the ionic species in soil samples. A next-generation MECA, the Robotic Chemical Analysis Laboratory (RCAL), uses a carousel-type system to allow for greater customization of analytical procedures. A second instrument, proposed as part of the 2007 CryoScout mission, consists of a flow-through inorganic chemical analyzer (MICA). CryoScout is a torpedo-like device designed for subsurface investigation of the stratigraphic climate record embedded in Mars' north polar cap. As the CryoScout melts its way through the ice cap, MICA will collect and analyze the meltwater for a variety of inorganics and chemical parameters. By analyzing the chemistry locked in the layers of dust, salt, and ice, geologists will be able to determine the recent history of climate, water, and atmosphere on Mars and link it to the past. Finally, electroanalysis shows its abilities in the detection of possible microorganism on Mars or elsewhere in the solar system. To identify an unknown microorganism, one that may not even use Earth-type biochemistry, requires a detection scheme which makes minimal assumptions and looks for the most general features. Recent work has demonstrated that the use of an array of electrochemical sensors which monitors the changes in a solution via electrical conductivity, pH, and ion selective electrodes, can be used to detect minute chemical perturbations caused by the growth of bacteria and

  6. Electrochemical approaches for chemical and biological analysis on Mars.

    PubMed

    Kounaves, Samuel P

    2003-02-17

    Obtaining in situ chemical data from planetary bodies such as Mars or Europa can present significant challenges. The one analytical technique that has many of the requisite characteristics to meet such a challenge is electroanalysis. Described here are three electroanalytical devices designed for in situ geochemical and biological analysis on Mars. The Mars Environmental Compatibility Assessment (MECA) was built and flight qualified for the now cancelled NASA Mars 2001 Lander. Part of MECA consisted of four "cells" containing arrays of electrochemical based sensors for measuring the ionic species in soil samples. A next-generation MECA, the Robotic Chemical Analysis Laboratory (RCAL), uses a carousel-type system to allow for greater customization of analytical procedures. A second instrument, proposed as part of the 2007 CryoScout mission, consists of a flow-through inorganic chemical analyzer (MICA). CryoScout is a torpedo-like device designed for subsurface investigation of the stratigraphic climate record embedded in Mars' north polar cap. As the CryoScout melts its way through the ice cap, MICA will collect and analyze the meltwater for a variety of inorganics and chemical parameters. By analyzing the chemistry locked in the layers of dust, salt, and ice, geologists will be able to determine the recent history of climate, water, and atmosphere on Mars and link it to the past. Finally, electroanalysis shows its abilities in the detection of possible microorganism on Mars or elsewhere in the solar system. To identify an unknown microorganism, one that may not even use Earth-type biochemistry, requires a detection scheme which makes minimal assumptions and looks for the most general features. Recent work has demonstrated that the use of an array of electrochemical sensors which monitors the changes in a solution via electrical conductivity, pH, and ion selective electrodes, can be used to detect minute chemical perturbations caused by the growth of bacteria and

  7. Systems analysis of past, present, and future chemical terrorism scenarios.

    SciTech Connect

    Hoette, Trisha Marie

    2012-03-01

    Throughout history, as new chemical threats arose, strategies for the defense against chemical attacks have also evolved. As a part of an Early Career Laboratory Directed Research and Development project, a systems analysis of past, present, and future chemical terrorism scenarios was performed to understand how the chemical threats and attack strategies change over time. For the analysis, the difficulty in executing chemical attack was evaluated within a framework of three major scenario elements. First, historical examples of chemical terrorism were examined to determine how the use of chemical threats, versus other weapons, contributed to the successful execution of the attack. Using the same framework, the future of chemical terrorism was assessed with respect to the impact of globalization and new technologies. Finally, the efficacy of the current defenses against contemporary chemical terrorism was considered briefly. The results of this analysis justify the need for continued diligence in chemical defense.

  8. Quantitative chemical analysis of ocular melanosomes in the TEM.

    PubMed

    Eibl, O; Schultheiss, S; Blitgen-Heinecke, P; Schraermeyer, U

    2006-01-01

    Melanosomes in retinal tissues of a human, monkey and rat were analyzed by EDX in the TEM. Samples were prepared by ultramicrotomy at different thicknesses. The material was mounted on Al grids and samples were analyzed in a Zeiss 912 TEM equipped with an Omega filter and EDX detector with ultrathin window. Melanosomes consist of C and O as main components, mole fractions are about 90 and 3-10 at.%, respectively, and small mole fraction ratios, between 2 and 0.1 at.%, of Na, Mg, K, Si, P, S, Cl, Ca. All elements were measured quantitatively by standardless EDX with high precision. Mole fractions of transition metals Fe, Cu and Zn were also measured. For Fe a mole fraction ratio of less than 0.1at.% was found and gives the melanin its paramagnetic properties. Its mole fraction is however close to or below the minimum detectable mass fraction of the used equipment. Only in the human eye and only in the retinal pigment epitelium (rpe) the mole fractions of Zn (0.1 at.% or 5000 microg/g) and Cu were clearly beyond the minimum detectable mass fraction. In the rat and monkey eye the mole fraction of Zn was at or below the minimum detectable mass fraction and could not be measured quantitatively. The obtained results yielded the chemical composition of the melanosomes in the choroidal tissue and the retinal pigment epitelium (rpe) of the three different species. The results of the chemical analysis are discussed by mole fraction correlation diagrams. Similarities and differences between the different species are outlined. Correlation behavior was found to hold over species, e.g. the Ca-O correlation. It indicates that Ca is bound to oxygen rich sites in the melanin. These are the first quantitative analyses of melanosomes by EDX reported so far. The quantitative chemical analysis should open a deeper understanding of the metabolic processes in the eye that are of central importance for the understanding of a large number of eye-related diseases. The chemical analysis also

  9. Using phylogenetic information and chemical properties to predict species tolerances to pesticides

    PubMed Central

    Guénard, Guillaume; Carsten von der Ohe, Peter; Carlisle Walker, Steven; Lek, Sovan; Legendre, Pierre

    2014-01-01

    Direct estimation of species' tolerance to pesticides and other toxic organic substances is a combinatorial problem, because of the large number of species–substance pairs. We propose a statistical modelling approach to predict tolerances associated with untested species–substance pairs, by using models fitted to tested pairs. This approach is based on the phylogeny of species and physico-chemical descriptors of pesticides, with both kinds of information combined in a bilinear model. This bilinear modelling approach predicts tolerance in untested species–compound pairs based on the facts that closely related species often respond similarly to toxic compounds and that chemically similar compounds often have similar toxic effects. The three tolerance models (median lethal concentration after 96 h) used up to 25 aquatic animal species and up to nine pesticides (organochlorines, organophosphates and carbamates). Phylogeny was estimated using DNA sequences, while the pesticides were described by their mode of toxic action and their octanol–water partition coefficients. The models explained 77–84% of the among-species variation in tolerance (log10 LC50). In cross-validation, 84–87% of the predicted tolerances for individual species were within a factor of 10 of the observed values. The approach can also be used to model other species response to multivariate stress factors. PMID:25009056

  10. Systematic Approach to Calculate the Concentration of Chemical Species in Multi-Equilibrium Problems

    ERIC Educational Resources Information Center

    Baeza-Baeza, Juan Jose; Garcia-Alvarez-Coque, Maria Celia

    2011-01-01

    A general systematic approach is proposed for the numerical calculation of multi-equilibrium problems. The approach involves several steps: (i) the establishment of balances involving the chemical species in solution (e.g., mass balances, charge balance, and stoichiometric balance for the reaction products), (ii) the selection of the unknowns (the…

  11. Responses of three darter species (genus Etheostoma) to chemical alarm cues from conspecifics and congeners

    Treesearch

    Amy M. Commens-Carson; Alicia Mathis

    2007-01-01

    Several species of darters of the genus Etheostoma possess a chemical alarm substance, but it is not known how widespread this substance is within the genus. We performed behavioral bioassays on Fantail Darters (E. flabellare), Rainbow Darters (E. caeruleum), and Redfin Darters (E. whipplei)....

  12. Chemical composition of Achillea schischkinii Sosn., an endemic species from Turkey

    USDA-ARS?s Scientific Manuscript database

    In this study, we investigated the chemical composition of an endemic species of Achillea schischkinii Sosn. (Asteraceae) collected from an eastern part of Turkey (Van). Air-dried aerial parts were subjected to water-distillation using a Clevenger-type system. The essential oil was analyzed by GC-MS...

  13. Systematic Approach to Calculate the Concentration of Chemical Species in Multi-Equilibrium Problems

    ERIC Educational Resources Information Center

    Baeza-Baeza, Juan Jose; Garcia-Alvarez-Coque, Maria Celia

    2011-01-01

    A general systematic approach is proposed for the numerical calculation of multi-equilibrium problems. The approach involves several steps: (i) the establishment of balances involving the chemical species in solution (e.g., mass balances, charge balance, and stoichiometric balance for the reaction products), (ii) the selection of the unknowns (the…

  14. Application of a framework for extrapolating chemical effects across species in pathways controlled by estrogen receptor-á

    EPA Science Inventory

    Cross-species extrapolation of toxicity data from limited surrogate test organisms to all wildlife with potential of chemical exposure remains a key challenge in ecological risk assessment. A number of factors affect extrapolation, including the chemical exposure, pharmacokinetic...

  15. Application of a framework for extrapolating chemical effects across species in pathways controlled by estrogen receptor-á

    EPA Science Inventory

    Cross-species extrapolation of toxicity data from limited surrogate test organisms to all wildlife with potential of chemical exposure remains a key challenge in ecological risk assessment. A number of factors affect extrapolation, including the chemical exposure, pharmacokinetic...

  16. Chemical profiles of body surfaces and nests from six Bornean stingless bee species.

    PubMed

    Leonhardt, Sara Diana; Blüthgen, Nico; Schmitt, Thomas

    2011-01-01

    Stingless bees (Apidae: Meliponini) are the most diverse group of Apid bees and represent common pollinators in tropical ecosystems. Like honeybees they live in large eusocial colonies and rely on complex chemical recognition and communication systems. In contrast to honeybees, their ecology and especially their chemical ecology have received only little attention, particularly in the Old World. We previously have analyzed the chemical profiles of six paleotropical stingless bee species from Borneo and revealed the presence of species-specific cuticular terpenes- an environmentally derived compound class so far unique among social insects. Here, we compared the bees' surface profiles to the chemistry of their nest material. Terpenes, alkanes, and alkenes were the dominant compound groups on both body surfaces and nest material. However, bee profiles and nests strongly differed in their chemical composition. Body surfaces thus did not merely mirror nests, rendering a passive compound transfer from nests to bees unlikely. The difference between nests and bees was particularly pronounced when all resin-derived compounds (terpenes) were excluded and only genetically determined compounds were considered. When terpenes were included, bee profiles and nest material still differed, because whole groups of terpenes (e.g., sesquiterpenes) were found in nest material of some species, but missing in their chemical profile, indicating that bees are able to influence the terpene composition both in their nests and on their surfaces.

  17. Structural analysis of photosystem I polypeptides using chemical crosslinking

    NASA Technical Reports Server (NTRS)

    Armbrust, T. S.; Odom, W. R.; Guikema, J. A.; Spooner, B. S. (Principal Investigator)

    1994-01-01

    Thylakoid membranes, obtained from leaves of 14 d soybean (Glycine max L. cv. Williams) plants, were treated with the chemical crosslinkers glutaraldehyde or 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) to investigate the structural organization of photosystem I. Polypeptides were resolved using lithium dodecyl sulfate polyacrylamide gel electrophoresis, and were identified by western blot analysis using a library of polyclonal antibodies specific for photosystem I subunits. An electrophoretic examination of crosslinked thylakoids revealed numerous crosslinked products, using either glutaraldehyde or EDC. However, only a few of these could be identified by western blot analysis using subunit-specific polyclonal antibodies. Several glutaraldehyde dependent crosslinked species were identified. A single band was identified minimally composed of PsaC and PsaD, documenting the close interaction between these two subunits. The most interesting aspect of these studies was a crosslinked species composed of the PsaB subunit observed following EDC treatment of thylakoids. This is either an internally crosslinked species, which will provide structural information concerning the topology of the complex PsaB protein, a linkage with a polypeptide for which we do not yet have an immunological probe, or a masking of epitopes by the EDC linkage at critical locations in the peptide which is linked to PsaB.

  18. Structural analysis of photosystem I polypeptides using chemical crosslinking.

    PubMed

    Armbrust, T S; Odom, W R; Guikema, J A

    1994-07-01

    Thylakoid membranes, obtained from leaves of 14 d soybean (Glycine max L. cv. Williams) plants, were treated with the chemical crosslinkers glutaraldehyde or 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) to investigate the structural organization of photosystem I. Polypeptides were resolved using lithium dodecyl sulfate polyacrylamide gel electrophoresis, and were identified by western blot analysis using a library of polyclonal antibodies specific for photosystem I subunits. An electrophoretic examination of crosslinked thylakoids revealed numerous crosslinked products, using either glutaraldehyde or EDC. However, only a few of these could be identified by western blot analysis using subunit-specific polyclonal antibodies. Several glutaraldehyde dependent crosslinked species were identified. A single band was identified minimally composed of PsaC and PsaD, documenting the close interaction between these two subunits. The most interesting aspect of these studies was a crosslinked species composed of the PsaB subunit observed following EDC treatment of thylakoids. This is either an internally crosslinked species, which will provide structural information concerning the topology of the complex PsaB protein, a linkage with a polypeptide for which we do not yet have an immunological probe, or a masking of epitopes by the EDC linkage at critical locations in the peptide which is linked to PsaB.

  19. SALI chemical analysis of provided samples

    NASA Technical Reports Server (NTRS)

    Becker, Christopher H.

    1993-01-01

    SRI has completed the chemical analysis of all the samples supplied by NASA. The final batch of four samples consisted of: one inch diameter MgF2 mirror, control 1200-ID-FL3; one inch diameter neat resin, PMR-15, AO171-IV-55, half exposed and half unexposed; one inch diameter chromic acid anodized, EOIM-3 120-47 aluminum disc; and AO-exposed and unexposed samples of fullerene extract material in powdered form, pressed into In foil for analysis. Chemical analyses of the surfaces were performed by the surface analysis by laser ionization (SALI) method. The analyses emphasize surface contamination or general organic composition. SALI uses nonselective photoionization of sputtered or desorbed atoms and molecules above but close (approximately one mm) to the surface, followed by time-of-flight (TOF) mass spectrometry. In these studies, we used laser-induced desorption by 5-ns pulse-width 355-nm light (10-100 mJ/sq cm) and single-photon ionization (SPI) by coherent 118-nm radiation (at approximately 5 x 10(exp 5) W/sq cm). SPI was chosen primarily for its ability to obtain molecular information, whereas multiphoton ionization (not used in the present studies) is intended primarily for elemental and small molecule information. In addition to these four samples, the Au mirror (EOIM-3 200-11, sample four) was depth profiled again. Argon ion sputtering was used together with photoionization with intense 355-nm radiation (35-ps pulsewidths). Depth profiles are similar to those reported earlier, showing reproducibility. No chromium was found in the sample above noise level; its presence could at most be at the trace level. Somewhat more Ni appears to be present in the Au layer in the unexposed side, indicating thermal diffusion without chemical enhancement. The result of the presence of oxygen is apparently to tie-up/draw out the Ni as an oxide at the surface. The exposed region has a brownish tint appearance to the naked eye.

  20. Quality assessment of cortex cinnamomi by HPLC chemical fingerprint, principle component analysis and cluster analysis.

    PubMed

    Yang, Jie; Chen, Li-Hong; Zhang, Qin; Lai, Mao-Xiang; Wang, Qiang

    2007-06-01

    HPLC fingerprint analysis, principle component analysis (PCA), and cluster analysis were introduced for quality assessment of Cortex cinnamomi (CC). The fingerprint of CC was developed and validated by analyzing 30 samples of CC from different species and geographic locations. Seventeen chromatographic peaks were selected as characteristic peaks and their relative peak areas (RPA) were calculated for quantitative expression of the HPLC fingerprints. The correlation coefficients of similarity in chromatograms were higher than 0.95 for the same species while much lower than 0.6 for different species. Besides, two principal components (PCs) have been extracted by PCA. PC1 separated Cinnamomum cassia from other species, capturing 56.75% of variance while PC2 contributed for their further separation, capturing 19.08% variance. The scores of the samples showed that the samples could be clustered reasonably into different groups corresponding to different species and different regions. The scores and loading plots together revealed different chemical properties of each group clearly. The cluster analysis confirmed the results of PCA analysis. Therefore, HPLC fingerprint in combination with chemometric techniques provide a very flexible and reliable method for quality assessment of traditional Chinese medicines.

  1. Master equation analysis of deterministic chemical chaos

    NASA Astrophysics Data System (ADS)

    Wang, Hongli; Li, Qianshu

    1998-05-01

    The underlying microscopic dynamics of deterministic chemical chaos was investigated in this paper. We analyzed the master equation for the Williamowski-Rössler model by direct stochastic simulation as well as in the generating function representation. Simulation within an ensemble revealed that in the chaotic regime the deterministic mass action kinetics is related neither to the ensemble mean nor to the most probable value within the ensemble. Cumulant expansion analysis of the master equation also showed that the molecular fluctuations do not admit bounded values but increase linearly in time infinitely, indicating the meaninglessness of the chaotic trajectories predicted by the phenomenological equations. These results proposed that the macroscopic description is no longer useful in the chaotic regime and a more microscopic description is necessary in this circumstance.

  2. Advanced development in chemical analysis of Cordyceps.

    PubMed

    Zhao, J; Xie, J; Wang, L Y; Li, S P

    2014-01-01

    Cordyceps sinensis, also called DongChongXiaCao (winter worm summer grass) in Chinese, is a well-known and valued traditional Chinese medicine. In 2006, we wrote a review for discussing the markers and analytical methods in quality control of Cordyceps (J. Pharm. Biomed. Anal. 41 (2006) 1571-1584). Since then this review has been cited by others for more than 60 times, which suggested that scientists have great interest in this special herbal material. Actually, the number of publications related to Cordyceps after 2006 is about 2-fold of that in two decades before 2006 according to the data from Web of Science. Therefore, it is necessary to review and discuss the advanced development in chemical analysis of Cordyceps since then. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Identification of chemical hazards for security risk analysis activities.

    SciTech Connect

    Jaeger, Calvin Dell

    2005-01-01

    The presentation outline of this paper is: (1) How identification of chemical hazards fits into a security risk analysis approach; (2) Techniques for target identification; and (3) Identification of chemical hazards by different organizations. The summary is: (1) There are a number of different methodologies used within the chemical industry which identify chemical hazards: (a) Some develop a manual listing of potential targets based on published lists of hazardous chemicals or chemicals of concern, 'expert opinion' or known hazards. (b) Others develop a prioritized list based on chemicals found at a facility and consequence analysis (offsite release affecting population, theft of material, product tampering). (2) Identification of chemical hazards should include not only intrinsic properties of the chemicals but also potential reactive chemical hazards and potential use for activities off-site.

  4. Sampling and physico-chemical analysis of precipitation: a review.

    PubMed

    Krupa, Sagar V

    2002-01-01

    Wet deposition is one of two processes governing the transfer of beneficial and toxic chemicals from the atmosphere on to surfaces. Since the early 1970s, numerous investigators have sampled and analyzed precipitation for their chemical constituents, in the context of "acidic rain" and related atmospheric processes. Since then, significant advances have been made in our understanding of how to sample rain, cloud and fog water to preserve their physico-chemical integrity prior to analyses. Since the 1970s large-scale precipitation sampling networks have been in operation to broadly address regional and multi-regional issues. However, in examining the results from such efforts at a site-specific level, concerns have been raised about the accuracy and precision of the information gathered. There is mounting evidence to demonstrate the instability of precipitation samples (e.g. with N species) that have been subjected to prolonged ambient or field conditions. At the present time precipitation sampling procedures allow unrefrigerated or refrigerated collection of wet deposition from individual events, sequential fractions within events, in situ continuous chemical analyses in the field and even sampling of single or individual rain, cloud and fog droplets. Similarly analytical procedures of precipitation composition have advanced from time-consuming methods to rapid and simultaneous analyses of major anions and cations, from bulk samples to single droplets. For example, analytical techniques have evolved from colorimetry to ion chromatography to capillary electrophoresis. Overall, these advances allow a better understanding of heterogeneous reactions and atmospheric pollutant scavenging processes by precipitation. In addition, from an environmental perspective, these advances allow better quantification of semi-labile (e.g. NH4+, frequently its deposition values are underestimated) or labile species [e.g. S (IV)] in precipitation and measurements of toxic chemicals such

  5. Semi-volatile inorganic species: importance for atmospheric chemical composition on diurnal and seasonal timescales

    NASA Astrophysics Data System (ADS)

    Pearce, Hana; Mann, Graham; Arnold, Stephen; O'Connor, Fiona; Benduhn, Francois; Rumbold, Steven; Pringle, Kirsty

    2016-04-01

    Nitrate aerosol has become an important driver of reduced European air quality and climate forcing, following reductions in sulphate precursor emissions since the 1980s, and is expected to be more influential in future decades. Measurements from the European Integrated Project on Aerosol and Cloud Climate Air Quality Interactions (EUCAARI) field campaign have shown that semi-volatile aerosol species such as ammonium nitrate can comprise a major component of the sub-micron particulate matter, particularly in high pollution episodes. This presentation will assess the contribution of semi-volatile inorganic aerosol to diurnal and seasonal cycles in atmospheric chemical composition over Europe. We use the UM-UKCA composition-climate model, including the GLOMAP interactive aerosol microphysics module and a recently developed 'hybrid' dissolution solver (HyDis) to accurately represent size-resolved partitioning of ammonia and nitric acid to the particle phase. In particular, we evaluate simulated size-resolved composition variations over Europe through the diurnal cycle, comparing hourly model output to Aerosol Mass Spectrometer observations at several sites during 2008. We will present the results of this composition analysis, in addition to model evaluation from comparisons with European Monitoring for Environmental Protection (EMEP) network and EUCAARI field campaign observations.

  6. Strong differences in chemical recognition cues between two closely related species of ants from the genus Lasius (Hymenoptera: Formicidae).

    PubMed

    Morrison, W R; Witte, V

    2011-11-01

    Cuticular hydrocarbons (CHCs) are increasingly recognized as important to insects and are used for constructing taxonomies. However, multiple parameters affect the expression of CHCs besides a genetic component. We propose that selection may act differently on the expression of CHCs, depending on the evolutionary context. To explore the influence of selection, the CHCs of two closely related ant species, Lasius niger and Lasius platythorax, were studied in a multidisciplinary approach. We characterized (i) CHCs and (ii) niches (through baiting, activity observations and foraging analysis). The species were distinct in both measures, although to a varying degree. Although they showed moderate niche partitioning along diet and environmental preferences, chemical differences were unexpectedly pronounced. This may be explained by divergent selection on mate recognition cues or by other influences on CHCs. Such striking chemical differences among closely related species may not be the rule and suggest that taxonomies based on CHCs should be interpreted cautiously; though, they remain useful tools for differentiating among cryptic species. © 2011 The Authors. Journal of Evolutionary Biology © 2011 European Society For Evolutionary Biology.

  7. The chemical species distribution and transformation of polyaluminum silicate chloride coagulant.

    PubMed

    Gao, Baoyu; Yue, Qinyan; Wang, Bingjian

    2002-02-01

    The chemical species distributions of polyaluminum silicate chloride (PASC) and polyaluminum chloride (PACl) determined by Al-Ferron complexation timed spectrophotometric and 27Al-NMR methods, respectively, have been compared and analyzed. The experimental results show that the species distribution and transformation of PASC are different from those of PACl, due to the interaction of polysilicic acid and hydrolyzed aluminum species. At the same basicity (B), the contents of, Al(b), Al13 and the monomer species Almono (also determined by 27Al-NMR) in PASC are lower than those in PACl, while the contents of Al(c) and the Alother determined by 27Al-NMR in PASC are higher than those in PACl. The differences between PASC and PACl with respect to these species enlarge as the molar ratio of Al/Si in PASC decreases. Further, in PACl the ratio of Al13 to Al(b) closes to 1.0, indicating that the amount of the two fractions are similar. In PASC, however, such an agreement does not exist at the lower B values and Al/Si molar ratios. When the B value and Al/Si molar ratios increase, however, the amount of Al13 and Al(b) species tends to close. The study findings indicate that polysilicic acid can react with hydrolyzed aluminum species to form an aluminum silicate polymer composite and result in the change in species distribution of PASC.

  8. Crucial roles of reactive chemical species in modification of respiratory syncytial virus by nitrogen gas plasma.

    PubMed

    Sakudo, Akikazu; Toyokawa, Yoichi; Imanishi, Yuichiro; Murakami, Tomoyuki

    2017-05-01

    The exact mechanisms by which nanoparticles, especially those composed of soft materials, are modified by gas plasma remain unclear. Here, we used respiratory syncytial virus (RSV), which has a diameter of 80-350nm, as a model system to identify important factors for gas plasma modification of nanoparticles composed of soft materials. Nitrogen gas plasma, generated by applying a short high-voltage pulse using a static induction (SI) thyristor power supply produced reactive chemical species (RCS) and caused virus inactivation. The plasma treatment altered the viral genomic RNA, while treatment with a relatively low concentration of hydrogen peroxide, which is a neutral chemical species among RCS, effectively inactivated the virus. Furthermore, a zero dimensional kinetic global model of the reaction scheme during gas plasma generation identified the production of various RCS, including neutral chemical species. Our findings suggest the nitrogen gas plasma generates RCS, including neutral species that damage the viral genomic RNA, leading to virus inactivation. Thus, RCS generated by gas plasma appears to be crucial for virus inactivation, suggesting this may constitute an important factor in terms of the efficient modification of nanoparticles composed of soft materials.

  9. Isolated and synergistic effects of chemical and structural defenses of two species of Tethya (Porifera: Demospongiae)

    NASA Astrophysics Data System (ADS)

    Ribeiro, Suzi Meneses; Cassiano, Keila Mara; Cavalcanti, Diana Negrão; Teixeira, Valéria Laneuville; Pereira, Renato Crespo

    2012-02-01

    Sponges are an important source of many interesting secondary metabolites with multiple ecological roles. Sponges can also use their spicules as a means of deterring consumers. The present study investigated the importance of chemicals and spicules as defensive strategies against predation for two congeneric sponge species from the Brazilian coast, Tethya rubra and Tethya maza. Crude extract and spicules differed somewhat in their effectiveness between these sponge species, with T. maza better defended than T. rubra against predation by the hermit crab Calcinus tibicen and synergistic effects stronger in T. rubra. These results show that defensive strategies may be similar between sponge species possessing monophyletic origin, and reveal the importance of research on congeneric species to understand the ecology and evolution of defensive strategies.

  10. Line-of-sight-attenuation chemical species tomography through the level set method

    NASA Astrophysics Data System (ADS)

    Twynstra, Matthew G.; Daun, Kyle J.; Waslander, Steven L.

    2014-08-01

    Chemical species tomography based on line-of-sight attenuation (LOSA-CST) is an emerging diagnostic for mapping the concentration of a gaseous species. Since laser absorption measurements alone are insufficient to specify a unique species concentration distribution, reconstruction algorithms must incorporate additional information that promotes presumed physical attributes of the distribution. This paper pioneers the application of the level set method to LOSA-CST. The species concentration distribution is initially represented by a signed distance function, which is progressively deformed by forces that scale with the difference between the measured and simulated absorption data, as well as deviation from spatial smoothness. The final distribution explains the LOSA data and is also qualitatively consistent with mixed advection/diffusion transport physics. The algorithm is demonstrated by solving a simulated laser tomography experiment on a turbulent methane plume.

  11. Some inconvenient truths about biosignatures involving two chemical species on Earth-like exoplanets

    PubMed Central

    Rein, Hanno; Fujii, Yuka; Spiegel, David S.

    2014-01-01

    The detection of strong thermochemical disequilibrium in the atmosphere of an extrasolar planet is thought to be a potential biosignature. In this article we present a previously unidentified kind of false positive that can mimic a disequilibrium or any other biosignature that involves two chemical species. We consider a scenario where the exoplanet hosts a moon that has its own atmosphere and neither of the atmospheres is in chemical disequilibrium. Our results show that the integrated spectrum of the planet and the moon closely resembles that of a single object in strong chemical disequilibrium. We derive a firm limit on the maximum spectral resolution that can be obtained for both directly imaged and transiting planets. The spectral resolution of even idealized space-based spectrographs that might be achievable in the next several decades is in general insufficient to break the degeneracy. Both chemical species can only be definitively confirmed in the same object if absorption features of both chemicals can be unambiguously identified and their combined depth exceeds 100%. PMID:24778224

  12. Some inconvenient truths about biosignatures involving two chemical species on Earth-like exoplanets.

    PubMed

    Rein, Hanno; Fujii, Yuka; Spiegel, David S

    2014-05-13

    The detection of strong thermochemical disequilibrium in the atmosphere of an extrasolar planet is thought to be a potential biosignature. In this article we present a previously unidentified kind of false positive that can mimic a disequilibrium or any other biosignature that involves two chemical species. We consider a scenario where the exoplanet hosts a moon that has its own atmosphere and neither of the atmospheres is in chemical disequilibrium. Our results show that the integrated spectrum of the planet and the moon closely resembles that of a single object in strong chemical disequilibrium. We derive a firm limit on the maximum spectral resolution that can be obtained for both directly imaged and transiting planets. The spectral resolution of even idealized space-based spectrographs that might be achievable in the next several decades is in general insufficient to break the degeneracy. Both chemical species can only be definitively confirmed in the same object if absorption features of both chemicals can be unambiguously identified and their combined depth exceeds 100%.

  13. Arbuscular mycorrhizal fungi alter above- and below-ground chemical defense expression differentially among Asclepias species

    PubMed Central

    Vannette, Rachel L.; Hunter, Mark D.; Rasmann, Sergio

    2013-01-01

    Below-ground (BG) symbionts of plants can have substantial influence on plant growth and nutrition. Recent work demonstrates that mycorrhizal fungi can affect plant resistance to herbivory and the performance of above- (AG) and BG herbivores. Although these examples emerge from diverse systems, it is unclear if plant species that express similar defensive traits respond similarly to fungal colonization, but comparative work may inform this question. To examine the effects of arbuscular mycorrhizal fungi (AMF) on the expression of chemical resistance, we inoculated 8 species of Asclepias (milkweed)—which all produce toxic cardenolides—with a community of AMF. We quantified plant biomass, foliar and root cardenolide concentration and composition, and assessed evidence for a growth-defense tradeoff in the presence and absence of AMF. As expected, total foliar and root cardenolide concentration varied among milkweed species. Importantly, the effect of mycorrhizal fungi on total foliar cardenolide concentration also varied among milkweed species, with foliar cardenolides increasing or decreasing, depending on the plant species. We detected a phylogenetic signal to this variation; AMF fungi reduced foliar cardenolide concentrations to a greater extent in the clade including A. curassavica than in the clade including A. syriaca. Moreover, AMF inoculation shifted the composition of cardenolides in AG and BG plant tissues in a species-specific fashion. Mycorrhizal inoculation changed the relative distribution of cardenolides between root and shoot tissue in a species-specific fashion, but did not affect cardenolide diversity or polarity. Finally, a tradeoff between plant growth and defense in non-mycorrhizal plants was mitigated completely by AMF inoculation. Overall, we conclude that the effects of AMF inoculation on the expression of chemical resistance can vary among congeneric plant species, and ameliorate tradeoffs between growth and defense. PMID:24065971

  14. Arbuscular mycorrhizal fungi alter above- and below-ground chemical defense expression differentially among Asclepias species.

    PubMed

    Vannette, Rachel L; Hunter, Mark D; Rasmann, Sergio

    2013-01-01

    Below-ground (BG) symbionts of plants can have substantial influence on plant growth and nutrition. Recent work demonstrates that mycorrhizal fungi can affect plant resistance to herbivory and the performance of above- (AG) and BG herbivores. Although these examples emerge from diverse systems, it is unclear if plant species that express similar defensive traits respond similarly to fungal colonization, but comparative work may inform this question. To examine the effects of arbuscular mycorrhizal fungi (AMF) on the expression of chemical resistance, we inoculated 8 species of Asclepias (milkweed)-which all produce toxic cardenolides-with a community of AMF. We quantified plant biomass, foliar and root cardenolide concentration and composition, and assessed evidence for a growth-defense tradeoff in the presence and absence of AMF. As expected, total foliar and root cardenolide concentration varied among milkweed species. Importantly, the effect of mycorrhizal fungi on total foliar cardenolide concentration also varied among milkweed species, with foliar cardenolides increasing or decreasing, depending on the plant species. We detected a phylogenetic signal to this variation; AMF fungi reduced foliar cardenolide concentrations to a greater extent in the clade including A. curassavica than in the clade including A. syriaca. Moreover, AMF inoculation shifted the composition of cardenolides in AG and BG plant tissues in a species-specific fashion. Mycorrhizal inoculation changed the relative distribution of cardenolides between root and shoot tissue in a species-specific fashion, but did not affect cardenolide diversity or polarity. Finally, a tradeoff between plant growth and defense in non-mycorrhizal plants was mitigated completely by AMF inoculation. Overall, we conclude that the effects of AMF inoculation on the expression of chemical resistance can vary among congeneric plant species, and ameliorate tradeoffs between growth and defense.

  15. Biogeographical Analysis of Chemical Co-Occurrence Data to ...

    EPA Pesticide Factsheets

    A challenge with multiple chemical risk assessment is the need to consider the joint behavior of chemicals in mixtures. To address this need, pharmacologists and toxicologists have developed methods over the years to evaluate and test chemical interaction. In practice, however, testing of chemical interaction more often comprises ad hoc binary combinations and rarely examines higher order combinations. One explanation for this practice is the belief that there are simply too many possible combinations of chemicals to consider. Indeed, under stochastic conditions the possible number of chemical combinations scales geometrically as the pool of chemicals increases. However, the occurrence of chemicals in the environment is determined by factors, economic in part, which favor some chemicals over others. We investigate methods from the field of biogeography, originally developed to study avian species co-occurrence patterns, and adapt these approaches to examine chemical co-occurrence. These methods were applied to a national survey of pesticide residues in 168 child care centers from across the country. Our findings show that pesticide co-occurrence in the child care center was not random but highly structured, leading to the co-occurrence of specific pesticide combinations. Thus, ecological studies of species co-occurrence parallel the issue of chemical co-occurrence at specific locations. Both are driven by processes that introduce structure in the pattern of co-o

  16. LSENS - GENERAL CHEMICAL KINETICS AND SENSITIVITY ANALYSIS CODE

    NASA Technical Reports Server (NTRS)

    Bittker, D. A.

    1994-01-01

    LSENS has been developed for solving complex, homogeneous, gas-phase, chemical kinetics problems. The motivation for the development of this program is the continuing interest in developing detailed chemical reaction mechanisms for complex reactions such as the combustion of fuels and pollutant formation and destruction. A reaction mechanism is the set of all elementary chemical reactions that are required to describe the process of interest. Mathematical descriptions of chemical kinetics problems constitute sets of coupled, nonlinear, first-order ordinary differential equations (ODEs). The number of ODEs can be very large because of the numerous chemical species involved in the reaction mechanism. Further complicating the situation are the many simultaneous reactions needed to describe the chemical kinetics of practical fuels. For example, the mechanism describing the oxidation of the simplest hydrocarbon fuel, methane, involves over 25 species participating in nearly 100 elementary reaction steps. Validating a chemical reaction mechanism requires repetitive solutions of the governing ODEs for a variety of reaction conditions. Analytical solutions to the systems of ODEs describing chemistry are not possible, except for the simplest cases, which are of little or no practical value. Consequently, there is a need for fast and reliable numerical solution techniques for chemical kinetics problems. In addition to solving the ODEs describing chemical kinetics, it is often necessary to know what effects variations in either initial condition values or chemical reaction mechanism parameters have on the solution. Such a need arises in the development of reaction mechanisms from experimental data. The rate coefficients are often not known with great precision and in general, the experimental data are not sufficiently detailed to accurately estimate the rate coefficient parameters. The development of a reaction mechanism is facilitated by a systematic sensitivity analysis

  17. LSENS - GENERAL CHEMICAL KINETICS AND SENSITIVITY ANALYSIS CODE

    NASA Technical Reports Server (NTRS)

    Bittker, D. A.

    1994-01-01

    LSENS has been developed for solving complex, homogeneous, gas-phase, chemical kinetics problems. The motivation for the development of this program is the continuing interest in developing detailed chemical reaction mechanisms for complex reactions such as the combustion of fuels and pollutant formation and destruction. A reaction mechanism is the set of all elementary chemical reactions that are required to describe the process of interest. Mathematical descriptions of chemical kinetics problems constitute sets of coupled, nonlinear, first-order ordinary differential equations (ODEs). The number of ODEs can be very large because of the numerous chemical species involved in the reaction mechanism. Further complicating the situation are the many simultaneous reactions needed to describe the chemical kinetics of practical fuels. For example, the mechanism describing the oxidation of the simplest hydrocarbon fuel, methane, involves over 25 species participating in nearly 100 elementary reaction steps. Validating a chemical reaction mechanism requires repetitive solutions of the governing ODEs for a variety of reaction conditions. Analytical solutions to the systems of ODEs describing chemistry are not possible, except for the simplest cases, which are of little or no practical value. Consequently, there is a need for fast and reliable numerical solution techniques for chemical kinetics problems. In addition to solving the ODEs describing chemical kinetics, it is often necessary to know what effects variations in either initial condition values or chemical reaction mechanism parameters have on the solution. Such a need arises in the development of reaction mechanisms from experimental data. The rate coefficients are often not known with great precision and in general, the experimental data are not sufficiently detailed to accurately estimate the rate coefficient parameters. The development of a reaction mechanism is facilitated by a systematic sensitivity analysis

  18. Chemical Composition and Antioxidant, Antinociceptive, and Anti-inflammatory Activities of Four Amazonian Byrsonima Species.

    PubMed

    Guilhon-Simplicio, Fernanda; Machado, Tallita Marques; do Nascimento, Leandro Flores; Souza, Rayanne da Silva; Koolen, Hector Henrique Ferreira; da Silva, Felipe Moura Araújo; Acho, Leonard Domingo Rosales; Dos Santos, Adair Roberto Soares; Cos, Paul; Pereira, Maria de Meneses; Lima, Emerson Silva

    2017-08-25

    Species of the Byrsonima genus are widely used in Brazil, especially for the treatment of gastrointestinal disorders. However, species from the Amazonian region are still poorly studied. Thus, we studied the antioxidant, antinociceptive, and anti-inflammatory activities of for Amazonian species, Byrsonima crispa, Byrsonima duckeana, Byrsonima garcibarrigae, and Byrsonima incarnata. Phenolic composition was determined by chemical and chromatographic methods. The aqueous extracts were evaluated in DPPH(•) , ABTS(+•) , and superoxide (O2(•-) ) tests, LPS-activated macrophage assay, and formalin test. All species contained a high phenolic and flavonoid content. We identified 15 phenolic compounds, including phenolic acids, hydroxycinnamic acids, flavonoids, and catechins. The extracts showed high antioxidant activity and were more active than quercetin at inhibiting nitric oxide release in the LPS-activated macrophage assay. B. duckeana and B. garcibarrigae showed higher in vivo antinociceptive and anti-inflammatory activities. B. garcibarrigae presented significant effect on the early phase of the formalin test, pointing to an antinociceptive mechanism distinct from traditional anti-inflammatory medicines. In conclusion, the pharmacological potential of these species is closely related to their flavonoid-rich chemical composition, which seems to act through antioxidant mechanisms. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  19. The influence of electrohydrodynamic flow on the distribution of chemical species in positive corona

    NASA Astrophysics Data System (ADS)

    Pontiga, Francisco; Yanallah, Khelifa; Bouazza, R.; Chen, Junhong

    2015-09-01

    A numerical simulation of positive corona discharge in air, including the effect of electrohydrodynamic (EHD) motion of the gas, has been carried out. Air flow is assumed to be confined between two parallel plates, and corona discharge is produced around a thin wire, midway between the plates. Therefore, fluid dynamics equations, including electrical forces, have been solved together with the continuity equation of each neutral species. The plasma chemical model included 24 chemical reactions and ten neutral species, in addition to electrons and positive ions. The results of the simulation have shown that the influence of EHD flow on the spatial distributions of the species is quite different depending on the species. Hence, reactive species like atomic oxygen and atomic nitrogen are confined to the vicinity of the wire, and they are weakly affected by the EHD gas motion. In contrast, nitrogen oxides and ozone are efficiently dragged outside the active region of the corona discharge by the EHD flow. This work was supported by the Spanish Government Agency ``Ministerio de Ciencia e Innovación'' under Contract No. FIS2011-25161.

  20. Factors Affecting Species Identifications of Blow Fly Pupae Based upon Chemical Profiles and Multivariate Statistics

    PubMed Central

    Kranz, William; Carroll, Clinton; Dixon, Darren A.; Goodpaster, John V.; Picard, Christine J.

    2017-01-01

    Alternative methods for the identification of species of blow fly pupae have been developed over the years that consist of the analyses of chemical profiles. However, the effect of biotic and abiotic factors that could influence the predictive manner for the tests have not been evaluated. The lipids of blowfly pupae (Cochliomyia macellaria, Lucilia cuprina, Lucilia sericata, and Phormia regina) were extracted in pentane, derivatized, and analyzed by total-vaporization solid phase microextraction gas chromatography-mass spectrometry (TV-SPME GC-MS). Peak areas for 26 compounds were analyzed. Here we evaluated one biotic factor (colonization) on four species of blow flies to determine how well a model produced from lipid profiles of colonized flies predicted the species of flies of offspring of wild-caught flies and found very good species identification following 10 generations of inbreeding. When we evaluated four abiotic factors in our fly rearing protocols (temperature, humidity, pupation substrate, and diet), we found that the ability to assign the chemical profile to the correct species was greatly reduced. PMID:28398264

  1. Factors Affecting Species Identifications of Blow Fly Pupae Based upon Chemical Profiles and Multivariate Statistics.

    PubMed

    Kranz, William; Carroll, Clinton; Dixon, Darren A; Goodpaster, John V; Picard, Christine J

    2017-04-11

    Alternative methods for the identification of species of blow fly pupae have been developed over the years that consist of the analyses of chemical profiles. However, the effect of biotic and abiotic factors that could influence the predictive manner for the tests have not been evaluated. The lipids of blowfly pupae (Cochliomyia macellaria, Lucilia cuprina, Lucilia sericata, and Phormia regina) were extracted in pentane, derivatized, and analyzed by total-vaporization solid phase microextraction gas chromatography-mass spectrometry (TV-SPME GC-MS). Peak areas for 26 compounds were analyzed. Here we evaluated one biotic factor (colonization) on four species of blow flies to determine how well a model produced from lipid profiles of colonized flies predicted the species of flies of offspring of wild-caught flies and found very good species identification following 10 generations of inbreeding. When we evaluated four abiotic factors in our fly rearing protocols (temperature, humidity, pupation substrate, and diet), we found that the ability to assign the chemical profile to the correct species was greatly reduced.

  2. Ethnopharmacological and Chemical Characterization of Salvia Species Used in Valencian Traditional Herbal Preparations

    PubMed Central

    Martínez-Francés, Vanessa; Hahn, Emeline; Ríos, Segundo; Rivera, Diego; Reich, Eike; Vila, Roser; Cañigueral, Salvador

    2017-01-01

    In Valencia Region (Spain), some wild and cultivated sages are used for medicinal purposes. Among them, Salvia officinalis subsp. lavandulifolia (SL) is widely employed and known for production of Spanish sage oil and herbal products. Nevertheless, it shares the market with S. blancoana subsp. mariolensis (SB) and, to a lesser extent, with their hybrid S. x hegelmaieri (SH). The knowledge on these two species is far low and confusion between them is possible. The aim of the present paper is to improve the ethnopharmacological, morphological and chemical knowledge of these sages, and to contribute to setting up quality specifications for improving identification and distinction from other Salvia species, such as, S. officinalis subsp. officinalis, S. x auriculata and S. microphylla var. microphylla. Samples were collected in Valencia Region and surrounding mountain areas during the ethnopharmacological field work. Twenty-nine medicinal uses were reported for SL, 13 of them being also recorded for SB. Of particular interest is a homemade liquor, used as digestive and known as “salvieta,” which is mainly prepared with SB. The macro- and microscopic characters are insufficient for identification of cut, crushed or powdered material. The study of the essential oil and a HPTLC (High Performance Thin Layer Chromatography) fingerprint of their extracts could help to distinguish SB from the other sages. The essential oil from dried aerial parts of SB (content: 1.8–4.5%) was characterized by GC-FID (Gas Chromatography with Flame Ionization Detector) and GC-MS (Gas Chromatography coupled to Mass Spectrometry) showing a composition close to that currently accepted for Spanish sage essential oil in the European Pharmacopoeia, ISO (International Standard Organization) and UNE (Una Norma Española) standards, with 1,8-cineole (13.7–45.7%) and camphor (12.1–28.6%) as major constituents. HPTLC methods, based on the analysis of hydroalcoholic and dichloromethane extracts

  3. Spectroscopic Chemical Analysis Methods and Apparatus

    NASA Technical Reports Server (NTRS)

    Hug, William F.; Reid, Ray D.

    2012-01-01

    This invention relates to non-contact spectroscopic methods and apparatus for performing chemical analysis and the ideal wavelengths and sources needed for this analysis. It employs deep ultraviolet (200- to 300-nm spectral range) electron-beam-pumped wide bandgap semiconductor lasers, incoherent wide bandgap semiconductor lightemitting devices, and hollow cathode metal ion lasers. Three achieved goals for this innovation are to reduce the size (under 20 L), reduce the weight [under 100 lb (.45 kg)], and reduce the power consumption (under 100 W). This method can be used in microscope or macroscope to provide measurement of Raman and/or native fluorescence emission spectra either by point-by-point measurement, or by global imaging of emissions within specific ultraviolet spectral bands. In other embodiments, the method can be used in analytical instruments such as capillary electrophoresis, capillary electro-chromatography, high-performance liquid chromatography, flow cytometry, and related instruments for detection and identification of unknown analytes using a combination of native fluorescence and/or Raman spectroscopic methods. This design provides an electron-beampumped semiconductor radiation-producing method, or source, that can emit at a wavelength (or wavelengths) below 300 nm, e.g. in the deep ultraviolet between about 200 and 300 nm, and more preferably less than 260 nm. In some variations, the method is to produce incoherent radiation, while in other implementations it produces laser radiation. In some variations, this object is achieved by using an AlGaN emission medium, while in other implementations a diamond emission medium may be used. This instrument irradiates a sample with deep UV radiation, and then uses an improved filter for separating wavelengths to be detected. This provides a multi-stage analysis of the sample. To avoid the difficulties related to producing deep UV semiconductor sources, a pumping approach has been developed that uses

  4. Soil chemical factors and grassland species density in Emas National Park (central Brazil).

    PubMed

    Amorim, P K; Batalha, M A

    2008-05-01

    Studies of grasslands on specific soil types suggest that different nutrients can limit biomass production and, hence, species composition and number. The Brazilian cerrado is the major savanna region in America and once covered about 2 million km(2), mainly in the Brazilian Central Plateau, under seasonal climate, with wet summer and dry winter. In view of the importance of soil chemical factors in the distribution of the vegetation forms within the Cerrado domain and which may influence the number of species, we analyzed some soil characteristics in three herbaceous vegetation forms -- hyperseasonal cerrado, seasonal cerrado, and wet grassland -- in Emas National Park, a core cerrado site, to investigate the relationship between number of species and soil characteristics. We collected vegetation and soil samples in these three vegetation forms and submitted the obtained data to multiple linear regression. We found out that aluminum and pH were the best predictors of species density, the former positively related to species density and the latter negatively related. Since the predictable variation in species density is important in determining areas of conservation, we can postulate that these two soil factors are indicators of high species density areas in tropical grasslands, which could be used in selecting priority sites for conservation.

  5. Estimation of chemical toxicity to wildlife species using interspecies correlation models.

    PubMed

    Raimondo, S; Mineau, P; Barron, M G

    2007-08-15

    Ecological risks to wildlife are typically assessed using toxicity data for relatively few species and with limited understanding of differences in species sensitivity to contaminants. Empirical interspecies correlation models were derived from LD50 values for 49 wildlife species and 951 chemicals. The standard wildlife test species Japanese quail (Coturnix japonica) and mallard (Anas platyrhynchos) were determined to be good surrogates for many species within the database. Cross-validation of all models predicted toxicity values within 5-fold and 10-fold of the actual values with 85 and 95% certainty, respectively. Model robustness was not consistently improved by developing correlation models within modes of action (MOA); however, improved models for neurotoxicants, carbamates, and direct acting organophosphorous acetylcholenesterase inhibiting compounds indicate that toxicity estimates may improve if MOA-specific models are built with robust datasets. There was a strong relationship between taxonomic distance and cross-validation prediction success (chi2 = 297, df = 12, p < 0.0001), with uncertainty increasing with larger taxonomic distance between the surrogate and predicted species. Interspecies toxicity correlations provide a tool for estimating contaminant sensitivity with known levels of uncertainty for a diversity of wildlife species.

  6. Chemical composition and larvicidal activity of several essential oils from Hypericum species from Tunisia.

    PubMed

    Rouis, Zyed; Laamari, Ali; Abid, Nabil; Elaissi, Ameur; Cioni, Pier Luigi; Flamini, Guido; Aouni, Mahjoub

    2013-02-01

    The chemical composition of the essential oils extracted from some Tunisian Hypericum species and their larvicidal activity against Culex pipiens larvae were evaluated. The chemical compositions of the essential oils from the aerial plant parts were analyzed using gas chromatography-mass spectrometry. One hundred and thirty-four compounds were identified, ranging between 85.1 and 95.4 % of the oil's composition. The components were monoterpene hydrocarbons, oxygenated monoterpenes, sesquiterpene hydrocarbons, oxygenated sesquiterpenes, non-terpenic hydrocarbons, and others. The larvicidal activity of the essential oils was evaluated using a method recommended by WHO. Larvicidal tests revealed that essential oils from the Hypericum species have a significant larvicidal activity against C. pipiens, with LC(50) ranging between 102.82 and 194.70 ppm. The most powerful essential oils against these larvae were Hypericum tomentosum and Hypericum humifusum samples, followed by the essential oil of Hypericum perforatum.

  7. Chemical Recognition of Active Oxygen Species on the Surface of Oxygen Evolution Reaction Electrocatalysts.

    PubMed

    Yang, Chunzhen; Fontaine, Olivier; Tarascon, Jean-Marie; Grimaud, Alexis

    2017-07-17

    Owing to the transient nature of the intermediates formed during the oxygen evolution reaction (OER) on the surface of transition metal oxides, their nature remains largely elusive by the means of simple techniques. The use of chemical probes is proposed, which, owing to their specific affinities towards different oxygen species, unravel the role played by these species on the OER mechanism. For that, tetraalkylammonium (TAA) cations, previously known for their surfactant properties, are introduced, which interact with the active oxygen sites and modify the hydrogen bond network on the surface of OER catalysts. Combining chemical probes with isotopic and pH-dependent measurements, it is further demonstrated that the introduction of iron into amorphous Ni oxyhydroxide films used as model catalysts deeply modifies the proton exchange properties, and therefore the OER mechanism and activity. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Main species and chemical pathways in cold atmospheric-pressure Ar + H2O plasmas

    NASA Astrophysics Data System (ADS)

    Liu, Dingxin; Sun, Bowen; Iza, Felipe; Xu, Dehui; Wang, Xiaohua; Rong, Mingzhe; Kong, Michael G.

    2017-04-01

    Cold atmospheric-pressure plasmas in Ar + H2O gas mixtures are a promising alternative to He + H2O plasmas as both can produce reactive oxygen species of relevance for many applications and argon is cheaper than helium. Although He + H2O plasmas have been the subject of multiple experimental and computational studies, Ar + H2O plasmas have received less attention. In this work we investigate the composition and chemical pathways in Ar + H2O plasmas by means of a global model that incorporates 57 species and 1228 chemical reactions. Water vapor concentrations from 1 ppm to saturation (32 000 ppm) are considered in the study and abrupt transitions in power dissipation channels, species densities and chemical pathways are found when the water concentration increases from 100 to 1000 ppm. In this region the plasma transitions from an electropositive discharge in which most power is coupled to electrons into an electronegative one in which most power is coupled to ions. While increasing electronegativity is also observed in He + H2O plasmas, in Ar + H2O plasmas the transition is more abrupt because Penning processes do not contribute to gas ionization and the changes in the electron energy distribution function and mean electron energy caused by the increasing water concentration result in electron-neutral excitation and ionization rates changing by many orders of magnitude in a relatively small range of water concentrations. Insights into the main chemical species and pathways governing the production and loss of electrons, O, OH, OH(A) and H2O2 are provided as part of the study.

  9. Chemical species in fly ash from coal-burning power plants

    SciTech Connect

    Hulett, L.D. Jr.; Weinberger, A.J.; Northcutt, K.J.; Ferguson, M.

    1980-12-19

    Fly ash specimens from four power plants in the Tennessee Valley Authority system have been separated into three matrices: glass, mullite-quartz, and magnetic spinel. Chemical species of trace elements are defined to a large extent by the matrices that contain them. The magnetic component of fly ash is ferrite. The mullit-quartz phase is relatively pure and can be recovered as a resource.

  10. Swedish chemical regulation: an overview and analysis.

    PubMed

    Löfstedt, Ragnar E

    2003-04-01

    This article begins with a review of the regulation of chemicals in Sweden over the past 30 years, focusing particularly on the 1997 Government Environmental Quality Bill, which called for a toxic-free society by the year 2020. The second part of the article analyzes why Sweden has taken this route. The third and final section discusses Sweden's present role in formulating present EU chemical regulation, such as the recent EU Chemical White Paper, and hypothesizes future impacts of Swedish chemical regulations on the EU itself.

  11. Tree Species Traits Influence Soil Physical, Chemical, and Biological Properties in High Elevation Forests

    PubMed Central

    Ayres, Edward; Steltzer, Heidi; Berg, Sarah; Wallenstein, Matthew D.; Simmons, Breana L.; Wall, Diana H.

    2009-01-01

    Background Previous studies have shown that plants often have species-specific effects on soil properties. In high elevation forests in the Southern Rocky Mountains, North America, areas that are dominated by a single tree species are often adjacent to areas dominated by another tree species. Here, we assessed soil properties beneath adjacent stands of trembling aspen, lodgepole pine, and Engelmann spruce, which are dominant tree species in this region and are distributed widely in North America. We hypothesized that soil properties would differ among stands dominated by different tree species and expected that aspen stands would have higher soil temperatures due to their open structure, which, combined with higher quality litter, would result in increased soil respiration rates, nitrogen availability, and microbial biomass, and differences in soil faunal community composition. Methodology/Principal Findings We assessed soil physical, chemical, and biological properties at four sites where stands of aspen, pine, and spruce occurred in close proximity to one-another in the San Juan Mountains, Colorado. Leaf litter quality differed among the tree species, with the highest nitrogen (N) concentration and lowest lignin∶N in aspen litter. Nitrogen concentration was similar in pine and spruce litter, but lignin∶N was highest in pine litter. Soil temperature and moisture were highest in aspen stands, which, in combination with higher litter quality, probably contributed to faster soil respiration rates from stands of aspen. Soil carbon and N content, ammonium concentration, and microbial biomass did not differ among tree species, but nitrate concentration was highest in aspen soil and lowest in spruce soil. In addition, soil fungal, bacterial, and nematode community composition and rotifer, collembolan, and mesostigmatid mite abundance differed among the tree species, while the total abundance of nematodes, tardigrades, oribatid mites, and prostigmatid mites did not

  12. Network structural analysis using directed graph for chemical reaction analysis in weakly-ionized plasmas

    NASA Astrophysics Data System (ADS)

    Nobuto, Kyosuke; Mizui, Yasutaka; Miyagi, Shigeyuki; Sakai, Osamu; Murakami, Tomoyuki

    2016-09-01

    We visualize complicated chemical reaction systems in weakly-ionized plasmas by analysing network structure for chemical processes, and calculate some indexes by assuming interspecies relationships to be a network to clarify them. With the current social evolution, the mean size of general data which we can use in computers grows huge, and significance of the data analysis increases. The methods of the network analysis which we focus on in this study do not depend on a specific analysis target, but the field where it has been already applied is still limited. In this study, we analyse chemical reaction systems in plasmas for configuring the network structure. We visualize them by expressing a reaction system in a specific plasma by a directed graph and examine the indexes and the relations with the characteristic of the species in the reaction system. For example, in the methane plasma network, the centrality index reveals importance of CH3 in an influential position of species in the reaction. In addition, silane and atmospheric pressure plasmas can be also visualized in reaction networks, suggesting other characteristics in the centrality indexes.

  13. The smell of change: warming affects species interactions mediated by chemical information.

    PubMed

    Sentis, Arnaud; Ramon-Portugal, Felipe; Brodeur, Jacques; Hemptinne, Jean-Louis

    2015-10-01

    Knowledge of how temperature influences an organism's physiology and behaviour is of paramount importance for understanding and predicting the impacts of climate change on species' interactions. While the behaviour of many organisms is driven by chemical information on which they rely on to detect resources, conspecifics, natural enemies and competitors, the effects of temperature on infochemical-mediated interactions remain largely unexplored. Here, we experimentally show that temperature strongly influences the emission of infochemicals by ladybeetle larvae, which, in turn, modifies the oviposition behaviour of conspecific females. Temperature also directly affects female perception of infochemicals and their oviposition behaviour. Our results suggest that temperature-mediated effects on chemical communication can influence flows across system boundaries (e.g. immigration and emigration) and thus alter the dynamics and stability of ecological networks. We therefore argue that investigating the effects of temperature on chemical communication is a crucial step towards a better understanding of the functioning of ecological communities facing rapid environmental changes.

  14. Use of chemical communication in the management of freshwater aquatic species that are vectors of human diseases or are invasive.

    PubMed

    Corkum, Lynda D; Belanger, Rachelle M

    2007-01-01

    Chemical communication occurs when both originator (signaller) and one or more receiver(s) possess specializations for chemical exchange of information. Chemical information can be used by a wide variety of species to locate food and mates, avoid predators and engage in social interactions. In this review, we focus on chemical signalling between mates or cues from nest sites or hosts by selected aquatic pest species and indicate how chemical information can be used to manage pests. The pests are vectors of disease (blood-sucking insects) or invasive species (crayfishes and fishes) that have exhibited detrimental effects on indigenous species. Pheromones released by females attract and stimulate males in some taxa (insects, crayfish, goldfish, and crucian carp), whereas pheromones released by males attract females in others (round goby, sea lamprey). Other chemicals (e.g., habitat odours or odours given off by developmental stages of conspecifics) can affect oviposition decisions of pest species. In areas of aquatic environments where other cues may be limited (e.g., visual), freshwater organisms may rely solely on chemical signals or in concert with environmental cues for reproduction. Once the chemical structure of odour attractants are identified and shown to lure conspecifics to traps, odorants or their blends can be used to control the aquatic pests. There is promise for the application of pheromone traps to control the malarian vector (Anopheles gambiae) or invasive species such as signal crayfish (Pacifastacus leniusculus), sea lamprey (Petromyzon marinus) and the round goby (Neogobius melanostomus) by disrupting the reproductive behaviours of these species.

  15. Exact probability distributions of selected species in stochastic chemical reaction networks.

    PubMed

    López-Caamal, Fernando; Marquez-Lago, Tatiana T

    2014-09-01

    Chemical reactions are discrete, stochastic events. As such, the species' molecular numbers can be described by an associated master equation. However, handling such an equation may become difficult due to the large size of reaction networks. A commonly used approach to forecast the behaviour of reaction networks is to perform computational simulations of such systems and analyse their outcome statistically. This approach, however, might require high computational costs to provide accurate results. In this paper we opt for an analytical approach to obtain the time-dependent solution of the Chemical Master Equation for selected species in a general reaction network. When the reaction networks are composed exclusively of zeroth and first-order reactions, this analytical approach significantly alleviates the computational burden required by simulation-based methods. By building upon these analytical solutions, we analyse a general monomolecular reaction network with an arbitrary number of species to obtain the exact marginal probability distribution for selected species. Additionally, we study two particular topologies of monomolecular reaction networks, namely (i) an unbranched chain of monomolecular reactions with and without synthesis and degradation reactions and (ii) a circular chain of monomolecular reactions. We illustrate our methodology and alternative ways to use it for non-linear systems by analysing a protein autoactivation mechanism. Later, we compare the computational load required for the implementation of our results and a pure computational approach to analyse an unbranched chain of monomolecular reactions. Finally, we study calcium ions gates in the sarco/endoplasmic reticulum mediated by ryanodine receptors.

  16. Assessment of conservative weighting scheme in simulating chemical vapour deposition with trace species

    NASA Astrophysics Data System (ADS)

    Wu, J.-S.; Hsiao, W.-J.; Lian, Y.-Y.; Tseng, K.-C.

    2003-09-01

    Low-pressure or ultra-high vacuum chemical vapour deposition often involves important trace species in both gas-phase and surface reactions. The conservative weighting scheme (J. Thermophys. Heat Transfer 1996; 10(4) : 579) has been used to deal with the trace species often involved in some non-reactive physical processes, which is otherwise considered computationally impossible using the conventional DSMC method. This conservative weighting scheme (CWS) improves greatly the statistical uncertainties by decreasing the weighting factors of trace-species particles and ensures the conservation of both momentum and energy between two colliding particles with large difference of weighting factors. This CWS is further extended to treat reactive processes for gas-phase and surface reactions with trace species, which is called extended conservative weighting scheme (ECWS). A single-cell equilibrium simulation is performed for verifying both the CWS and ECWS in treating trace species. The results of using CWS show that it is most efficient and accurate for weight ratio (trace to non-trace) equal to or less than 0.01 for flows with two and three species. The results of a single-cell simulation using ECWS for gas-phase reaction and surface reactions show that only ECWS can produce acceptable results with reasonable computational time.

  17. Novel chemical species of Santilli’s magnegas in hadronic chemistry

    SciTech Connect

    Zodape, Sangesh P.

    2015-03-10

    In this paper we have reviewed the novel chemical species, the magnecules, synthesized by Santilli that comprises of individual atoms, radicals and ordinary molecules bonded through the magnetic attractive forces originating out of toroidal polarization of the orbitals of atomic electrons under strong magnetic fields. The main focus of this paper is to review the fabulous applications of Santill’s magnegas. The novel magnecular species of hydrogen and oxygen find their place in fuel industry especially in fuel cells with the increase in its power, efficiency and total output. In this account we have also considered the flame temperature report of the new magnecular species of gases. We emphasize the importance of this new field.

  18. Bioeconomic analysis supports the endangered species act.

    PubMed

    Salau, Kehinde R; Fenichel, Eli P

    2015-10-01

    The United States Endangered Species Act (ESA) was enacted to protect and restore declining fish, wildlife, and plant populations. The ESA mandates endangered species protection irrespective of costs. This translates to the restriction of activities that harm endangered populations. We discuss criticisms of the ESA in the context of public land management and examine under what circumstance banning non-conservation activity on multiple use federal lands can be socially optimal. We develop a bioeconomic model to frame the species management problem under the ESA and identify scenarios where ESA-imposed regulations emerge as optimal strategies. Results suggest that banning harmful activities is a preferred strategy when valued endangered species are in decline or exposed to poor habitat quality. However, it is not optimal to sustain such a strategy in perpetuity. An optimal plan involves a switch to land-use practices characteristic of habitat conservation plans.

  19. Metabolomic Analysis of Three Mollicute Species

    PubMed Central

    Vanyushkina, Anna A.; Fisunov, Gleb Y.; Gorbachev, Alexey Y.; Kamashev, Dmitri E.; Govorun, Vadim M.

    2014-01-01

    We present a systematic study of three bacterial species that belong to the class Mollicutes, the smallest and simplest bacteria, Spiroplasma melliferum, Mycoplasma gallisepticum, and Acholeplasma laidlawii. To understand the difference in the basic principles of metabolism regulation and adaptation to environmental conditions in the three species, we analyzed the metabolome of these bacteria. Metabolic pathways were reconstructed using the proteogenomic annotation data provided by our lab. The results of metabolome, proteome and genome profiling suggest a fundamental difference in the adaptation of the three closely related Mollicute species to stress conditions. As the transaldolase is not annotated in Mollicutes, we propose variants of the pentose phosphate pathway catalyzed by annotated enzymes for three species. For metabolite detection we employed high performance liquid chromatography coupled with mass spectrometry. We used liquid chromatography method - hydrophilic interaction chromatography with silica column - as it effectively separates highly polar cellular metabolites prior to their detection by mass spectrometer. PMID:24595068

  20. Multilocus sequence analysis of phytopathogenic species of the genus Streptomyces

    USDA-ARS?s Scientific Manuscript database

    The identification and classification of species within the genus Streptomyces is difficult because there are presently 576 validly described species and this number increases every year. The value of the application of multilocus sequence analysis scheme to the systematics of Streptomyces species h...

  1. Selecting focal species as surrogates for imperiled species using relative sensitivities derived from occupancy analysis

    USGS Publications Warehouse

    Silvano, Amy; Guyer, Craig; Steury, Todd; Grand, James B.

    2017-01-01

    Most imperiled species are rare or elusive and difficult to detect, which makes gathering data to estimate their response to habitat restoration a challenge. We used a repeatable, systematic method for selecting focal species using relative sensitivities derived from occupancy analysis. Our objective was to select suites of focal species that would be useful as surrogates when predicting effects of restoration of habitat characteristics preferred by imperiled species. We developed 27 habitat profiles that represent general habitat relationships for 118 imperiled species. We identified 23 regularly encountered species that were sensitive to important aspects of those profiles. We validated our approach by examining the correlation between estimated probabilities of occupancy for species of concern and focal species selected using our method. Occupancy rates of focal species were more related to occupancy rates of imperiled species when they were sensitive to more of the parameters appearing in profiles of imperiled species. We suggest that this approach can be an effective means of predicting responses by imperiled species to proposed management actions. However, adequate monitoring will be required to determine the effectiveness of using focal species to guide management actions.

  2. 29Si NMR Chemical Shift Calculation for Silicate Species by Gaussian Software

    NASA Astrophysics Data System (ADS)

    Azizi, S. N.; Rostami, A. A.; Godarzian, A.

    2005-05-01

    Hartree-Fock self-consistent-field (HF-SCF) theory and the Gauge-including atomic orbital (GIAO) methods are used in the calculation of 29Si NMR chemical shifts for ABOUT 90 units of 19 compounds of various silicate species of precursors for zeolites. Calculations have been performed at geometries optimized at the AM1 semi-empirical method. The GIAO-HF-SCF calculations were carried out with using three different basis sets: 6-31G*, 6-31+G** and 6-311+G(2d,p). To demonstrate the quality of the calculations the calculated chemical shifts, δ, were compared with the corresponding experimental values for the compounds in study. The results, especially with 6-31+g** are in excellent agreement with experimental values. The calculated chemical shifts, in practical point of view, appear to be accurate enough to aid in experimental peak assignments. The difference between the experimental and calculated 29Si chemical shift values not only depends on the Qn units but also it seems that basis set effects and the level of theory is more important. For the series of molecules studied here, the standard deviations and mean absolute errors for 29Si chemical shifts relative to TMS determined using Hartree--Fock 6-31+G** basis is nearly in all cases smaller than the errors for shifts determined using HF/6-311+G(2d,p).

  3. Evaluation of morphological and chemical aspects of different wood species by spectroscopy and thermal methods

    NASA Astrophysics Data System (ADS)

    Popescu, Maria-Cristina; Popescu, Carmen-Mihaela; Lisa, Gabriela; Sakata, Yusaku

    2011-03-01

    The aim of this study is to find the most convenient procedure to make an easy differentiation between various kinds of wood. The wood samples used were: fir (Acer alba), poplar (Populus tremula), lime (Tillia cordata), sycamore (Acer pseudoplatanus), sweet cherry (Prunus avium), hornbeam (Carpinus betulus), walnut (Juglans regia), beech (Fagus sylvatica), oak (Quercus robur). The methods of investigation used were FT-IR spectroscopy, X-ray diffraction and thermogravimetry. By FT-IR spectroscopy, was observed that the ratio values of lignin/carbohydrate IR bands for wood decreases with increasing the average wood density, showing a decrease in lignin content. Also, the calculated values of lignin percentage from the FT-IR spectra are in very good correlation with the values from literature. Following the deconvolution process of the X-ray diffraction patterns, it was found that the degree of crystallinity, the apparent lateral crystallite size, the proportion of crystallite interior chains and cellulose fraction tend to increase with increasing of the wood density. Thermal analysis is able to give information about degradation temperatures for the principal components of different wood samples. The shape of DTG curves depends on the wood species that cause the enlargement of the peaks or the maxima of the decomposition step varies at larger or smaller temperatures ranges. The temperatures and weight loss percentage are particular for each kind of wood. This study showed that analytical methods used have the potential to be important sources of information for a quick evaluation of the chemical composition of wood samples.

  4. Higher allocation to low cost chemical defenses in invasive species of Hawaii.

    PubMed

    Peñuelas, Josep; Sardans, J; Llusia, J; Owen, S M; Silva, J; Niinemets, U

    2010-11-01

    The capacity to produce carbon-based secondary compounds (CBSC), such as phenolics (including tannins) and terpenes as defensive compounds against herbivores or against neighboring competing plants can be involved in the competition between alien and native plant species. Since the Hawaiian Islands are especially vulnerable to invasions by alien species, we compared total phenolic (TP), total tannin (Tta), and total terpene (TT) leaf contents of alien and native plants on Oahu Island (Hawaii). We analyzed 35 native and 38 alien woody plant species randomly chosen among representative current Hawaiian flora. None of these CBSC exhibited phylogenetic fingerprinting. Alien species had similar leaf TP and leaf Tta contents, and 135% higher leaf TT contents compared with native species. Alien plants had 80% higher leaf TT:N leaf content ratio than native plants. The results suggest that apart from greater growth rate and greater nutrient use, alien success in Oahu also may be linked to greater contents of low cost chemical defenses, such as terpenes, as expected in faster-growing species in resource rich regions. The higher TT contents in aliens may counterbalance their lower investment in leaf structural defenses and their higher leaf nutritional quality. The higher TT provides higher effectiveness in deterring the generalist herbivores of the introduced range, where specialist herbivores are absent. In addition, higher TT contents may favor aliens conferring higher protection against abiotic and biotic stressors. The higher terpene accumulation was independent of the alien species origin, which indicates that being alien either selects for higher terpene contents post-invasion, or that species with high terpene contents are pre-adapted to invasiveness. Although less likely, an originally lower terpene accumulation in Hawaiian than in continental plants that avoids the increased attraction of specialist enemies associated to terpenes may not be discarded.

  5. Smells Like Home: Chemically Mediated Co-Habitation of Two Termite Species in a Single Nest.

    PubMed

    Jirošová, Anna; Sillam-Dussès, David; Kyjaková, Pavlína; Kalinová, Blanka; Dolejšová, Klára; Jančařík, Andrej; Majer, Pavel; Cristaldo, Paulo Fellipe; Hanus, Robert

    2016-10-01

    Termite nests often are referred to as the most elaborate constructions of animals. However, some termite species do not build a nest at all and instead found colonies inside the nests of other termites. Since these so-called inquilines do not need to be in direct contact with the host population, the two colonies usually live in separate parts of the nest. Adaptations of both the inquiline and its host are likely to occur to maintain the spatial exclusion and reduce the costs of potential conflicts. Among them, mutual avoidance, based on chemical cues, is expected. We investigated chemical aspects of cohabitation between Constrictotermes cavifrons (Nasutitermitinae) and its obligatory inquiline Inquilinitermes inquilinus (Termitinae). Inquiline soldiers produce in their frontal glands a blend of wax esters, consisting of the C12 alcohols (3Z)-dodec enol, (3Z,6Z)-dodecadienol, and dodecanol, esterified with different fatty acids. The C12 alcohols appear to be cleaved gradually from the wax esters, and they occur in the frontal gland, in soldier headspace, and in the walls of the inquiline part of the nest. Electrophysiological experiments revealed that (3Z)-dodecenol and (3Z,6Z)-dodecadienol are perceived by workers of both species. Bioassays indicated that inquiline soldier heads, as well as the two synthetic compounds, are attractive to conspecific workers and elicit an arresting behavior, while host soldiers and workers avoid these chemicals at biologically relevant amounts. These observations support the hypothesis that chemically mediated spatial separation of the host and the inquiline is an element of a conflict-avoidance strategy in these species.

  6. Sequence Alignment to Predict Across Species Susceptibility (SeqAPASS): A web-based tool for addressing the challenges of cross-species extrapolation of chemical toxicity

    EPA Science Inventory

    Conservation of a molecular target across species can be used as a line-of-evidence to predict the likelihood of chemical susceptibility. The web-based Sequence Alignment to Predict Across Species Susceptibility (SeqAPASS) tool was developed to simplify, streamline, and quantitat...

  7. Sequence Alignment to Predict Across Species Susceptibility (SeqAPASS): A web-based tool for addressing the challenges of cross-species extrapolation of chemical toxicity

    EPA Science Inventory

    Conservation of a molecular target across species can be used as a line-of-evidence to predict the likelihood of chemical susceptibility. The web-based Sequence Alignment to Predict Across Species Susceptibility (SeqAPASS) tool was developed to simplify, streamline, and quantitat...

  8. Hydrogenation of CO-bearing species on grains: unexpected chemical desorption of CO

    NASA Astrophysics Data System (ADS)

    Minissale, M.; Moudens, A.; Baouche, S.; Chaabouni, H.; Dulieu, F.

    2016-05-01

    The amount of methanol in the gas phase and the CO depletion from the gas phase are still open problems in astrophysics. In this work, we investigate solid-state hydrogenation of CO-bearing species via H-exposure of carbon monoxide, formaldehyde, and methanol-thin films deposited on cold surfaces, paying attention to the possibility of a return to the gas phase. The products are probed via infrared spectroscopy (reflection absorption infrared spectroscopy), and two types of mass spectroscopy protocols: temperature-programmed desorption, and during-exposure desorption techniques. In the case of the [CO+H] reactive system, we have found that chemical desorption of CO is more efficient than H-addition reactions and HCO and H2CO formation; the studies of the [H2CO +H] reactive system show a strong competition between all surface processes, chemical desorption of H2CO, H-addition (CH3OH formation) and H-abstraction (CO formation); finally, [CH3OH + H] seems to be a non-reactive system and chemical desorption of methanol is not efficient. CO-bearing species present a see-saw mechanism between CO and H2CO balanced by the competition of H-addition and H2-abstraction that enhances the CO chemical desorption. The chemical network leading to methanol has to be reconsidered. The methanol formation on the surface of interstellar dust grain is still possible through CO+H reaction; nevertheless, its consumption of adsorbed H atoms should be higher than previously expected.

  9. Shedding light on the biological and chemical fingerprints of three Achillea species (A. biebersteinii, A. millefolium and A. teretifolia).

    PubMed

    Zengin, Gokhan; Aktumsek, Abdurrahman; Ceylan, Ramazan; Uysal, Sengul; Mocan, Andrei; Guler, Gokalp Ozmen; Mahomoodally, M Fawzi; Glamočlija, Jasmina; Ćirić, Ana; Soković, Marina

    2017-03-22

    Representatives of the Achillea genus are widely used as foods or nutraceuticals. Considering the increasing demand for herbal dietary supplements with health promoting effects, the objective of this research was to evaluate the biological and chemical profiles of different extracts (ethyl acetate, methanol and water) obtained from three Achillea species (A. biebersteinii, A. millefolium and A. teretifolia). The antioxidant (free radical scavenging (DPPH and ABTS), reducing power (CUPRAC and FRAP), metal chelating and phosphomolybdenum), enzyme inhibitory (anti-cholinesterase, anti-tyrosinase, anti-amylase and anti-glucosidase) and antimicrobial (antibacterial and antifungal) effects were assessed to investigate their biological profiles. Moreover, the total phenolic and flavonoid contents were determined and LC-MS analysis was performed for the chemical profile of the investigated extracts. The LC-MS analysis revealed the presence of several caffeoylquinic acids in these extracts. Generally, the methanol and water extracts exhibited stronger antioxidant abilities, which correlated with the higher levels of phenolic compounds when compared to the ethyl acetate extracts. In addition, the best antimicrobial activities were obtained for the ethyl acetate and methanolic extracts. However, the ethyl acetate extract had remarkable enzyme inhibitory potential. On the basis of our results, Achillea species may be promoted as promising sources of natural agents and used for the development of nutraceuticals or functional food ingredients.

  10. CHEMICAL ANALYSIS METHODS FOR ATMOSPHERIC AEROSOL COMPONENTS

    EPA Science Inventory

    This chapter surveys the analytical techniques used to determine the concentrations of aerosol mass and its chemical components. The techniques surveyed include mass, major ions (sulfate, nitrate, ammonium), organic carbon, elemental carbon, and trace elements. As reported in...

  11. CHEMICAL ANALYSIS METHODS FOR ATMOSPHERIC AEROSOL COMPONENTS

    EPA Science Inventory

    This chapter surveys the analytical techniques used to determine the concentrations of aerosol mass and its chemical components. The techniques surveyed include mass, major ions (sulfate, nitrate, ammonium), organic carbon, elemental carbon, and trace elements. As reported in...

  12. Forecasting for energy and chemical decision analysis

    SciTech Connect

    Cazalet, E.G.

    1984-08-01

    This paper focuses on uncertainty and bias in forecasts used for major energy and chemical investment decisions. Probability methods for characterizing uncertainty in the forecast are reviewed. Sources of forecasting bias are classified based on the results of relevant psychology research. Examples are drawn from the energy and chemical industry to illustrate the value of explicit characterization of uncertainty and reduction of bias in forecasts.

  13. Differential Sharing of Chemical Cues by Social Parasites Versus Social Mutualists in a Three-Species Symbiosis.

    PubMed

    Emery, Virginia J; Tsutsui, Neil D

    2016-04-01

    Chemical recognition systems are crucial for maintaining the unity of social insect colonies. It has been proposed that colonies form a common chemical signature, called the gestalt odor, which is used to distinguish colony members and non-members. This chemical integration is achieved actively through social interactions such as trophallaxis and allogrooming, or passively such as through exposure to common nest material. When colonies are infiltrated by social parasites, the intruders often use some form of chemical mimicry. However, it is not always clear how this chemical mimicry is accomplished. Here, we used a three-species nesting symbiosis to test the differences in chemical integration of mutualistic (parabiotic) and parasitic ant species. We found that the parasite (Solenopsis picea) obtains chemical cues from both of the two parabiotic host ant species. However, the two parabiotic species (Crematogaster levior and Camponotus femoratus) maintain species-specific cues, and do not acquire compounds from the other species. Our findings suggest that there is a fundamental difference in how social mutualists and social parasites use chemicals to integrate themselves into colonies.

  14. Chemical Engineering Data Analysis Made Easy with DataFit

    ERIC Educational Resources Information Center

    Brenner, James R.

    2006-01-01

    The outline for half of a one-credit-hour course in analysis of chemical engineering data is presented, along with a range of typical problems encountered later on in the chemical engineering curriculum that can be used to reinforce the data analysis skills learned in the course. This mini course allows students to be exposed to a variety of ChE…

  15. Differentiation of neotropical fish species with statistical analysis of fourier transform infrared photoacoustic spectroscopy data.

    PubMed

    Almeida, Francylaine S; Lima, Sandro M; Andrade, Luis H C; Súarez, Yzel R

    2012-07-01

    Fourier transform infrared photoacoustic spectroscopy (FTIR-PAS) was applied to nineteen fish species in Brazil's Upper Paraná River basin to identify differences in the structural composition of their scales. To differentiate the species, a canonical discriminant analysis was used to indicate the most important absorption peaks in the mid-infrared region. Significant differences were found in the chemical composition of scales among the studied fish species, with Wilk's lambda = 5.2 × 10(-6), F((13,18,394)) = 37.57, and P < 0.001, indicating that O-CH(2) wag at 1396 cm(-1) can be used as a biomarker of this species group. The species could be categorized into four groups according to phylogenetic similarity, suggesting that the O-CH(2) 1396 cm(-1) absorbance is related to the biological traits of each species. This procedure can also be used to complement evolutionary studies.

  16. Field-effect detection of chemical species with hybrid organic/inorganic transistors

    NASA Astrophysics Data System (ADS)

    Bartic, C.; Campitelli, A.; Borghs, S.

    2003-01-01

    In this letter, we demonstrate that organic-based transistors are able to detect charged/uncharged chemical species in aqueous media via the field effect. The chemical sensitivity of the organic transistors is illustrated for protons and glucose. The electrochemical potential developed at the solution/dielectric interface depends on the proton concentration in solution and it modifies the current flowing in the transistor according to this concentration. Glucose can also be detected if an enzymatic layer is coupled to the dielectric surface. An inorganic proton-sensitive dielectric, Ta2O5, is used in the transistor structure in order to reduce the operational voltages. The field-effect detection of chemical species allows us to realize sensors for a variety of ions/molecules if layers with a specific functionality are added to the transistor. Organic-based sensing devices show great potential for low-cost, health-related, and environmental applications because of their very simple fabrication process, which leads to disposability.

  17. Biological activities and chemical constituents of some mangrove species from Sundarban estuary: An overview

    PubMed Central

    Simlai, Aritra; Roy, Amit

    2013-01-01

    This review represents the studies performed on some beneficial mangrove plants such as Ceriops decandra, Xylocarpus granatum, Xylocarpus moluccensis, Excoecaria agallocha, Sarcolobus globosus, Sonneratia caseolaris and Acanthus ilicifolius from the Sundarban estuary spanning India and Bangladesh with regard to their biological activities and chemical investigations till date. Sundarban is the largest single chunk of mangrove forest in the world. The forest is a source of livelihood to numerous people of the region. Several of its plant species have very large applications in the traditional folk medicine; various parts of these plants are used by the local people as cure for various ailments. Despite such enormous potential, remarkably few reports are available on these species regarding their biological activities and the active principles responsible for such activities. Though some chemical studies have been made on the mangrove plants of this estuary, reports pertaining to their activity-structure relationship are few in number. An attempt has been made in this review to increase the awareness for the medicinal significance as well as conservation and utilization of these mangrove species as natural rich sources of novel bioactive agents. PMID:24347925

  18. Chemically engineering ligand selectivity at the free fatty acid receptor 2 based on pharmacological variation between species orthologs

    PubMed Central

    Hudson, Brian D.; Christiansen, Elisabeth; Tikhonova, Irina G.; Grundmann, Manuel; Kostenis, Evi; Adams, David R.; Ulven, Trond; Milligan, Graeme

    2012-01-01

    When it is difficult to develop selective ligands within a family of related G-protein-coupled receptors (GPCRs), chemically engineered receptors activated solely by synthetic ligands (RASSLs) are useful alternatives for probing receptor function. In the present work, we explored whether a RASSL of the free fatty acid receptor 2 (FFA2) could be developed on the basis of pharmacological variation between species orthologs. For this, bovine FFA2 was characterized, revealing distinct ligand selectivity compared with human FFA2. Homology modeling and mutational analysis demonstrated a single mutation in human FFA2 of C4.57G resulted in a human FFA2 receptor with ligand selectivity similar to the bovine receptor. This was exploited to generate human FFA2-RASSL by the addition of a second mutation at a known orthosteric ligand interaction site, H6.55Q. The resulting FFA2-RASSL displayed a >100-fold loss of activity to endogenous ligands, while responding to the distinct ligand sorbic acid with pEC50 values for inhibition of cAMP, 5.83 ± 0.11; Ca2+ mobilization, 4.63 ± 0.05; ERK phosphorylation, 5.61 ± 0.06; and dynamic mass redistribution, 5.35 ± 0.06. This FFA2-RASSL will be useful in future studies on this receptor and demonstrates that exploitation of pharmacological variation between species orthologs is a powerful method to generate novel chemically engineered GPCRs.—Hudson, B. D., Christiansen, E., Tikhonova, I. G., Grundmann, M., Kostenis, E., Adams, D. R., Ulven, T., Milligan, G. Chemically engineering ligand selectivity at the free fatty acid receptor 2 based on pharmacological variation between species orthologs. PMID:22919070

  19. Analysis of silicon transporters in turfgrass species

    USDA-ARS?s Scientific Manuscript database

    Silicon is an abundant element on earth and is also known to be beneficial as an amendment in some crops such as rice. Despite its abundance in many soils, accumulation of silicon in plants is species-specific and can be widely different. It has been shown that the genes responsible for silicon upta...

  20. Seasonal variation in content, chemical composition and antimicrobial and cytotoxic activities of essential oils from four Mentha species.

    PubMed

    Hussain, Abdullah I; Anwar, Farooq; Nigam, Poonam S; Ashraf, Muhammad; Gilani, Anwarul H

    2010-08-30

    The aim of the present study was to appraise variation in the chemical composition, and antimicrobial and cytotoxic activities of essential oils from the leaves of four Mentha species-M. arvensis, M. piperita, M. longifolia and M. spicata-as affected by harvesting season. Disc diffusion and broth microdilution susceptibility assays were used to evaluate the antimicrobial activity of Mentha essential oils against a panel of microorganisms. The cytotoxicity of essential oils was tested on breast cancer (MCF-7) and prostate cancer (LNCaP) cell lines using the MTT assay. The essential oil contents of M. arvensis, M. piperita, M. longifolia and M. spicata were 17.0, 12.2, 10.8 and 12.0 g kg(-1) from the summer and 9.20, 10.5, 7.00 and 9.50 g kg(-1) from the winter crops, respectively. Gas chromatographic-mass spectrometric analysis revealed that mostly quantitative rather than qualitative variation was observed in the oil composition of each species. The principal chemical constituents determined in M. arvensis, M. piperita, M. longifolia and M. spicata essential oils from both seasons were menthol, menthone, piperitenone oxide and carvone, respectively. The tested essential oils and their major components exhibited notable antimicrobial activity against most of the plant and human pathogens tested. The tested essential oils also exhibited good cytotoxicity potential. Of the Mentha essential oils tested, M. arvensis essential oil showed relatively better antimicrobial and cytotoxic activities. A significant variation in the content of most of the chemical components and biological activities of seasonally collected samples was documented. Copyright (c) 2010 Society of Chemical Industry.

  1. Development of micellar reactive oxygen species assay for photosafety evaluation of poorly water-soluble chemicals.

    PubMed

    Seto, Yoshiki; Kato, Masashi; Yamada, Shizuo; Onoue, Satomi

    2013-09-01

    A reactive oxygen species (ROS) assay was previously developed for photosafety assessment; however, the phototoxic potential of some chemicals cannot be evaluated because of their limited aqueous solubility. The present study was undertaken to develop a new micellar ROS (mROS) assay system for poorly water-soluble chemicals using a micellar solution of 0.5% (v/v) Tween 20 for solubility enhancement. In repeated mROS assay, intra- and inter-day precisions (coefficient of variation) were found to be below 11%, and the Z'-factors for singlet oxygen and superoxide suggested a large separation band between positive and negative standards. The ROS and mROS assays were applied to 65 phototoxins and 18 non-phototoxic compounds for comparative purposes. Of all 83 chemicals, 25 were unevaluable in the ROS assay due to poor solubility, but only 2 were in the mROS assay. Upon mROS assay on these model chemicals, the individual specificity was 76.5%, and the positive and negative predictivities were found to be 93.9% and 86.7%, respectively. The mROS assay provided 2 false negative predictions, although negative predictivity for the ROS assay was found to be 100%. Considering the pros and cons of these assays, strategic combined use of the ROS and mROS assays might be efficacious for reliable photosafety assessment with high applicability and predictivity. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Chemical diversity as a function of temperature in six northern diatom species.

    PubMed

    Huseby, Siv; Degerlund, Maria; Eriksen, Gunilla K; Ingebrigtsen, Richard A; Eilertsen, Hans Chr; Hansen, Espen

    2013-10-30

    In this study, we investigate how metabolic fingerprints are related to temperature. Six common northern temperate diatoms (Attheya longicornis, Chaetoceros socialis, Chaetoceros furcellatus, Porosira glacialis, Skeletonema marinoi, and Thalassiosira gravida) were cultivated at two different temperatures, 0.5 and 8.5 °C. To exclude metabolic variations due to differences in growth rates, the growth rates were kept similar by performing the experiments under light limited conditions but in exponential growth phase. Growth rates and maximum quantum yield of photosynthesis were measured and interpreted as physiological variables, and metabolic fingerprints were acquired by high-resolution mass spectrometry. The chemical diversity varied substantially between the two temperatures for the tested species, ranging from 31% similarity for C. furcellatus and P. glacialis to 81% similarity for A. longicornis. The chemical diversity was generally highest at the lowest temperature.

  3. Corymbia species and hybrids: chemical and physical foliar attributes and implications for herbivory.

    PubMed

    Nahrung, Helen F; Waugh, Rachel; Andrew Hayes, Richard

    2009-09-01

    Hybridization is an important biological phenomenon that can be used to understand the evolutionary process of speciation of plants and their associated pests and diseases. Interactions between hybrid plants and the herbivores of the parental taxa may be used to elucidate the various cues being used by the pests for host location or other processes. The chemical composition of plants, and their physical foliar attributes, including leaf thickness, trichome density, moisture content and specific leaf weight were compared between allopatric pure and commercial hybrid species of Corymbia, an important subtropical hardwood taxon. The leaf-eating beetle Paropsis atomaria, to which the pure taxa represented host (C. citriodora subsp. variegata) and non-host (C. torelliana) plants, was used to examine patterns of herbivory in relation to these traits. Hybrid physical foliar traits, chemical profiles, and field and laboratory beetle feeding preference, while showing some variability, were generally intermediate to those exhibited by parent taxa, thus suggesting an additive inheritance pattern. The hybrid susceptibility hypothesis was not supported by our field or laboratory studies, and there was no strong relationship between adult preference and larval performance. The most-preferred adult host was the sympatric taxon, although this species supported the lowest larval survival, while the hybrid produced significantly smaller pupae than the pure species. The results are discussed in relation to plant chemistry and physical characteristics. The findings suggest a chemical basis for host selection behavior and indicate that it may be possible to select for resistance to this insect pest in these commercially important hardwood trees.

  4. Contribution of species-specific chemical signatures to soil organic matter in Kohala, HI.

    NASA Astrophysics Data System (ADS)

    Stewart, C. E.; Amatangelo, K.; Neff, J. C.

    2008-12-01

    Soil organic matter (SOM) inherits much of its chemical structure from the dominant vegetation, including phenolic (lignin-derived), aromatic, and aliphatic (cutin and wax-derived) compounds. The Hawaiian fern species Dicranopteris decomposes more slowly than the angiosperm, Cheirodendron due to high concentrations of recalcitrant C compounds. These aliphatic fern leaf waxes are well-preserved and may comprise a large portion of the recalcitrant organic matter in these soils. Our objective was to determine the chemical signature of fern and angiosperm vegetation types and trace the preservation or loss of those compounds into the soil. We collected live tissue, litter, roots, and soil (<53 μm) from five dominant vegetation types including two angiosperms Cheirodendron and Metrosideros, two basal ferns Dicranopteris and Cibotium and a polypod fern Diplazium in Kohala, HI. We characterized them via TMAH-pyrolysis-gas chromatography-mass spectrometry. We found distinct chemical differences between angiosperm and fern vegetation; angiosperm contained more G- and S-derived lignin structures and the fern species contained greater relative abundances of P-derived lignin and tannin-derivatives. There was a general decrease of lignin-derived phenolic compounds from live to litter to soils and an increase in more recalcitrant, aromatic and aliphatic C. Recalcitrant fern-derived cutin and leaf waxes (alkene and alkanes structures) were evident in the soils, but clear species differences were not observed. Although ferns contain distinct lipid and wax-derived compounds, soils developed under fern do not appear to accumulate these compounds in SOM.

  5. Predicting aquatic toxicities of chemical pesticides in multiple test species using nonlinear QSTR modeling approaches.

    PubMed

    Basant, Nikita; Gupta, Shikha; Singh, Kunwar P

    2015-11-01

    In this study, we established nonlinear quantitative-structure toxicity relationship (QSTR) models for predicting the toxicities of chemical pesticides in multiple aquatic test species following the OECD (Organization for Economic Cooperation and Development) guidelines. The decision tree forest (DTF) and decision tree boost (DTB) based QSTR models were constructed using a pesticides toxicity dataset in Selenastrum capricornutum and a set of six descriptors. Other six toxicity data sets were used for external validation of the constructed QSTRs. Global QSTR models were also constructed using the combined dataset of all the seven species. The diversity in chemical structures and nonlinearity in the data were evaluated. Model validation was performed deriving several statistical coefficients for the test data and the prediction and generalization abilities of the QSTRs were evaluated. Both the QSTR models identified WPSA1 (weighted charged partial positive surface area) as the most influential descriptor. The DTF and DTB QSTRs performed relatively better than the single decision tree (SDT) and support vector machines (SVM) models used as a benchmark here and yielded R(2) of 0.886 and 0.964 between the measured and predicted toxicity values in the complete dataset (S. capricornutum). The QSTR models applied to six other aquatic species toxicity data yielded R(2) of >0.92 (DTF) and >0.97 (DTB), respectively. The prediction accuracies of the global models were comparable with those of the S. capricornutum models. The results suggest for the appropriateness of the developed QSTR models to reliably predict the aquatic toxicity of chemicals and can be used for regulatory purpose.

  6. Plant Species Rather Than Climate Greatly Alters the Temporal Pattern of Litter Chemical Composition During Long-Term Decomposition

    NASA Astrophysics Data System (ADS)

    Li, Yongfu; Chen, Na; Harmon, Mark E.; Li, Yuan; Cao, Xiaoyan; Chappell, Mark A.; Mao, Jingdong

    2015-10-01

    A feedback between decomposition and litter chemical composition occurs with decomposition altering composition that in turn influences the decomposition rate. Elucidating the temporal pattern of chemical composition is vital to understand this feedback, but the effects of plant species and climate on chemical changes remain poorly understood, especially over multiple years. In a 10-year decomposition experiment with litter of four species (Acer saccharum, Drypetes glauca, Pinus resinosa, and Thuja plicata) from four sites that range from the arctic to tropics, we determined the abundance of 11 litter chemical constituents that were grouped into waxes, carbohydrates, lignin/tannins, and proteins/peptides using advanced 13C solid-state NMR techniques. Decomposition generally led to an enrichment of waxes and a depletion of carbohydrates, whereas the changes of other chemical constituents were inconsistent. Inconsistent convergence in chemical compositions during decomposition was observed among different litter species across a range of site conditions, whereas one litter species converged under different climate conditions. Our data clearly demonstrate that plant species rather than climate greatly alters the temporal pattern of litter chemical composition, suggesting the decomposition-chemistry feedback varies among different plant species.

  7. Plant Species Rather Than Climate Greatly Alters the Temporal Pattern of Litter Chemical Composition During Long-Term Decomposition

    PubMed Central

    Li, Yongfu; Chen, Na; Harmon, Mark E.; Li, Yuan; Cao, Xiaoyan; Chappell, Mark A.; Mao, Jingdong

    2015-01-01

    A feedback between decomposition and litter chemical composition occurs with decomposition altering composition that in turn influences the decomposition rate. Elucidating the temporal pattern of chemical composition is vital to understand this feedback, but the effects of plant species and climate on chemical changes remain poorly understood, especially over multiple years. In a 10-year decomposition experiment with litter of four species (Acer saccharum, Drypetes glauca, Pinus resinosa, and Thuja plicata) from four sites that range from the arctic to tropics, we determined the abundance of 11 litter chemical constituents that were grouped into waxes, carbohydrates, lignin/tannins, and proteins/peptides using advanced 13C solid-state NMR techniques. Decomposition generally led to an enrichment of waxes and a depletion of carbohydrates, whereas the changes of other chemical constituents were inconsistent. Inconsistent convergence in chemical compositions during decomposition was observed among different litter species across a range of site conditions, whereas one litter species converged under different climate conditions. Our data clearly demonstrate that plant species rather than climate greatly alters the temporal pattern of litter chemical composition, suggesting the decomposition-chemistry feedback varies among different plant species. PMID:26515033

  8. Plant Species Rather Than Climate Greatly Alters the Temporal Pattern of Litter Chemical Composition During Long-Term Decomposition.

    PubMed

    Li, Yongfu; Chen, Na; Harmon, Mark E; Li, Yuan; Cao, Xiaoyan; Chappell, Mark A; Mao, Jingdong

    2015-10-30

    A feedback between decomposition and litter chemical composition occurs with decomposition altering composition that in turn influences the decomposition rate. Elucidating the temporal pattern of chemical composition is vital to understand this feedback, but the effects of plant species and climate on chemical changes remain poorly understood, especially over multiple years. In a 10-year decomposition experiment with litter of four species (Acer saccharum, Drypetes glauca, Pinus resinosa, and Thuja plicata) from four sites that range from the arctic to tropics, we determined the abundance of 11 litter chemical constituents that were grouped into waxes, carbohydrates, lignin/tannins, and proteins/peptides using advanced (13)C solid-state NMR techniques. Decomposition generally led to an enrichment of waxes and a depletion of carbohydrates, whereas the changes of other chemical constituents were inconsistent. Inconsistent convergence in chemical compositions during decomposition was observed among different litter species across a range of site conditions, whereas one litter species converged under different climate conditions. Our data clearly demonstrate that plant species rather than climate greatly alters the temporal pattern of litter chemical composition, suggesting the decomposition-chemistry feedback varies among different plant species.

  9. Karyotype analysis in Brachiaria (Poaceae) species.

    PubMed

    Bernini, C; Marin-Morales, M A

    2001-01-01

    This is the first karyotype characterization of Brachiaria species. Twelve accessions belonging to five species were analysed. The basic chromosome number was x = 9 and 7, the same reported for the tribe Paniceae. Variations in the chromosome number were observed in B. decumbens (2n = 18; 36) and B. humidicola (2n = 36; 42; 54). Chromosome numbers of 2n = 18 in B. ruziziensis and 2n = 36 in B. brizantha and B. jubata were recorded. Inter- and intraspecific karyotype differentiation of the accessions analysed was facilitated by variations in karyotypic symmetry. The karyotypes were generally considered symmetrical, with a tendency to asymmetry in the direction of the polyploids. It is suggested that addition, deletions and mainly polyploidy have been the most direct causes involved in the chromosome evolution of this genus.

  10. The biological activities and chemical composition of Pereskia species (Cactaceae)--a review.

    PubMed

    Pinto, Nícolas de Castro Campos; Scio, Elita

    2014-09-01

    The exploration of nature as a source of sustainable, novel bioactive substances continues to grow as natural products play a significant role in the search for new therapeutic and agricultural agents. In this context, plants of the genus Pereskia (Cactaceae) have been studied for their biological activities, and are evolving as an interesting subject in the search for new, bioactive compounds. These species are commonly used as human foodstuffs and in traditional medicine to treat a variety of diseases. This review focuses on the bioactivity and chemical composition of the genus Pereskia, and aims to stimulate further studies on the chemistry and biological potential of the genus.

  11. Pharmacological activity and chemical composition of callus culture extracts from selected species of Phyllanthus.

    PubMed

    Catapan, E; Otuki, M F; Viana, A M; Yunes, R A; Bresciani, L F; Ferreira, J; Santos, A R; Calixto, J B; Cechinel-Filho, V

    2000-12-01

    This study was conducted in order to determine the chemical composition and the possible antinociceptive effects in mice of some species of Phyllanthus in vitro. The methanolic extracts obtained from callus cultures of P. fraternus, P. stipulatus and P. caroliniensis caused significant inhibition in to the late phase of the formalin test, whereas the extract from P. urinaria inhibited both neurogenic and inflammatory phases of the test. Conventional chromatographic methods (TLC, GC) permitted the detection of some steroids or triterpenes, including beta-sitosterol, glochidonol and glochidone, which seem be responsible for the antinociceptive effects of the callus extracts studied.

  12. Comparison of the physico-chemical and phytochemical characteristics of the oil of two Plukenetia species.

    PubMed

    Chirinos, Rosana; Pedreschi, Romina; Domínguez, Gilberto; Campos, David

    2015-04-15

    A physico-chemical and phytochemical characterisation of the oil of two rich sources of polyunsaturated fatty acids, tocopherols and phytosterols is presented for two close species of Plukenetia, endemic to the Amazon Region of Peru. Plukenetia huayllabambana presented approximately 9% more oil yield than Plukenetia volubilis. Fatty acid profiles were pretty similar for both species but P. huayllabambana presented a significantly higher content of α-linolenic acid than P. volubilis (51.3 and 45.6 g/100 g oil, respectively). Important contents of γ- and δ-tocopherol were evidenced in both oils (127.6 and 84.0 and, 93.3 and 47.5 mg/100 g oil, for P. volubilis and P. huayllabambana, respectively). β-Sitosterol was the most important and representative phytosterol in both oils (∼127 mg/100 g oil). The results of this study indicate P. huayllabambana as an important dietary source of health promoting phytochemicals.

  13. Broadband chemical species tomography: Measurement theory and a proof-of-concept emission detection experiment

    NASA Astrophysics Data System (ADS)

    Grauer, Samuel J.; Tsang, Roger W.; Daun, Kyle J.

    2017-09-01

    This work introduces broadband-absorption based chemical species tomography (CST) as a novel approach to reconstruct hydrocarbon concentrations from open-path attenuation measurements. In contrast to monochromatic CST, which usually involves solving a mathematically ill-posed linear problem, the measurement equations in broadband CST are nonlinear due to the integration of the radiative transfer equation over the detection spectrum. We present a transfer function that relates broadband transmittances to a path-integrated concentration, suitable for tomographic reconstruction, and use a Bayesian reconstruction technique that combines the measurement data with a priori assumptions about the spatial distribution of the target species. The technique is demonstrated by reconstructing a propane plume, and validating the results by point concentration measurements made with a flame ionization detector.

  14. Chemical compositions and larvicidal activities of leaf essential oils from two eucalyptus species.

    PubMed

    Cheng, Sen-Sung; Huang, Chin-Gi; Chen, Ying-Ju; Yu, Jane-Jane; Chen, Wei-June; Chang, Shang-Tzen

    2009-01-01

    In the current study, the mosquito larvicidal activity of leaf essential oils and their constituents from two eucalyptus species (Eucalyptus camaldulensis and Eucalyptus urophylla) against two mosquito species, Aedes aegypti and Aedes albopictus, was investigated. In addition, the chemical compositions of the leaf essential oils were analyzed using gas chromatography-mass spectrometry. Results from the larvicidal tests revealed that essential oil from the leaves of E. camaldulensis had an excellent inhibitory effect against both A. aegypti and A. albopictus larvae. The 12 pure constituents extracted from the two eucalyptus leaf essential oils were also tested individually against two mosquito larvae. Among the six effective constituents, alpha-terpinene exhibits the best larvicidal effect against both A. aegypti and A. albopictus larvae. Results of this study show that the leaf essential oil of E. camaldulensis and its effective constituents might be considered as a potent source for the production of fine natural larvicides.

  15. Relative sensitivity of Arctic species to physically and chemically dispersed oil determined from three hydrocarbon measures of aquatic toxicity.

    PubMed

    Bejarano, Adriana C; Gardiner, William W; Barron, Mace G; Word, Jack Q

    2017-09-15

    The risks to Arctic species from oil releases is a global concern, but their sensitivity to chemically dispersed oil has not been assessed using a curated and standardized dataset from spiked declining tests. Species sensitivity to dispersed oil was determined by their position within species sensitivity distributions (SSDs) using three measures of hydrocarbon toxicity: total petroleum hydrocarbons (TPH), polycyclic aromatic hydrocarbon (PAHs), and naphthalenes. Comparisons of SSDs with Arctic/sub-Arctic versus non-Arctic species, and across SSDs of compositionally similar oils, showed that Arctic and non-Arctic species have comparable sensitivities even with the variability introduced by combining data across studies and oils. Regardless of hydrocarbon measure, hazard concentrations across SSDs were protective of sensitive Arctic species. While the sensitivities of Arctic species to oil exposures resemble those of commonly tested species, PAH-based toxicity data are needed for a greater species diversity including sensitive Arctic species. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Comparison of the chemical compositions and nutritive values of various pumpkin (Cucurbitaceae) species and parts

    PubMed Central

    Kim, Mi Young; Kim, Eun Jin; Kim, Young-Nam; Choi, Changsun

    2012-01-01

    Pumpkins have considerable variation in nutrient contents depending on the cultivation environment, species, or part. In this study, the general chemical compositions and some bioactive components, such as tocopherols, carotenoids, and β-sitosterol, were analyzed in three major species of pumpkin (Cucurbitaceae pepo, C. moschata, and C. maxima) grown in Korea and also in three parts (peel, flesh, and seed) of each pumpkin species. C. maxima had significantly more carbohydrate, protein, fat, and fiber than C. pepo or C. moschata (P < 0.05). The moisture content as well as the amino acid and arginine contents in all parts of the pumpkin was highest in C. pepo. The major fatty acids in the seeds were palmitic, stearic, oleic, and linoleic acids. C. pepo and C. moschata seeds had significantly more γ-tocopherol than C. maxima, whose seeds had the highest β-carotene content. C. pepo seeds had significantly more β-sitosterol than the others. Nutrient compositions differed considerably among the pumpkin species and parts. These results will be useful in updating the nutrient compositions of pumpkin in the Korean food composition database. Additional analyses of various pumpkins grown in different years and in different areas of Korea are needed. PMID:22413037

  17. Comparison of the chemical compositions and nutritive values of various pumpkin (Cucurbitaceae) species and parts.

    PubMed

    Kim, Mi Young; Kim, Eun Jin; Kim, Young-Nam; Choi, Changsun; Lee, Bog-Hieu

    2012-02-01

    Pumpkins have considerable variation in nutrient contents depending on the cultivation environment, species, or part. In this study, the general chemical compositions and some bioactive components, such as tocopherols, carotenoids, and β-sitosterol, were analyzed in three major species of pumpkin (Cucurbitaceae pepo, C. moschata, and C. maxima) grown in Korea and also in three parts (peel, flesh, and seed) of each pumpkin species. C. maxima had significantly more carbohydrate, protein, fat, and fiber than C. pepo or C. moschata (P < 0.05). The moisture content as well as the amino acid and arginine contents in all parts of the pumpkin was highest in C. pepo. The major fatty acids in the seeds were palmitic, stearic, oleic, and linoleic acids. C. pepo and C. moschata seeds had significantly more γ-tocopherol than C. maxima, whose seeds had the highest β-carotene content. C. pepo seeds had significantly more β-sitosterol than the others. Nutrient compositions differed considerably among the pumpkin species and parts. These results will be useful in updating the nutrient compositions of pumpkin in the Korean food composition database. Additional analyses of various pumpkins grown in different years and in different areas of Korea are needed.

  18. Chemical Discrimination of Cortex Phellodendri amurensis and Cortex Phellodendri chinensis by Multivariate Analysis Approach

    PubMed Central

    Sun, Hui; Wang, Huiyu; Zhang, Aihua; Yan, Guangli; Han, Ying; Li, Yuan; Wu, Xiuhong; Meng, Xiangcai; Wang, Xijun

    2016-01-01

    Background: As herbal medicines have an important position in health care systems worldwide, their current assessment, and quality control are a major bottleneck. Cortex Phellodendri chinensis (CPC) and Cortex Phellodendri amurensis (CPA) are widely used in China, however, how to identify species of CPA and CPC has become urgent. Materials and Methods: In this study, multivariate analysis approach was performed to the investigation of chemical discrimination of CPA and CPC. Results: Principal component analysis showed that two herbs could be separated clearly. The chemical markers such as berberine, palmatine, phellodendrine, magnoflorine, obacunone, and obaculactone were identified through the orthogonal partial least squared discriminant analysis, and were identified tentatively by the accurate mass of quadruple-time-of-flight mass spectrometry. A total of 29 components can be used as the chemical markers for discrimination of CPA and CPC. Of them, phellodenrine is significantly higher in CPC than that of CPA, whereas obacunone and obaculactone are significantly higher in CPA than that of CPC. Conclusion: The present study proves that multivariate analysis approach based chemical analysis greatly contributes to the investigation of CPA and CPC, and showed that the identified chemical markers as a whole should be used to discriminate the two herbal medicines, and simultaneously the results also provided chemical information for their quality assessment. SUMMARY Multivariate analysis approach was performed to the investigate the herbal medicineThe chemical markers were identified through multivariate analysis approachA total of 29 components can be used as the chemical markers. UPLC-Q/TOF-MS-based multivariate analysis method for the herbal medicine samples Abbreviations used: CPC: Cortex Phellodendri chinensis, CPA: Cortex Phellodendri amurensis, PCA: Principal component analysis, OPLS-DA: Orthogonal partial least squares discriminant analysis, BPI: Base peaks ion

  19. Chemical Discrimination of Cortex Phellodendri amurensis and Cortex Phellodendri chinensis by Multivariate Analysis Approach.

    PubMed

    Sun, Hui; Wang, Huiyu; Zhang, Aihua; Yan, Guangli; Han, Ying; Li, Yuan; Wu, Xiuhong; Meng, Xiangcai; Wang, Xijun

    2016-01-01

    As herbal medicines have an important position in health care systems worldwide, their current assessment, and quality control are a major bottleneck. Cortex Phellodendri chinensis (CPC) and Cortex Phellodendri amurensis (CPA) are widely used in China, however, how to identify species of CPA and CPC has become urgent. In this study, multivariate analysis approach was performed to the investigation of chemical discrimination of CPA and CPC. Principal component analysis showed that two herbs could be separated clearly. The chemical markers such as berberine, palmatine, phellodendrine, magnoflorine, obacunone, and obaculactone were identified through the orthogonal partial least squared discriminant analysis, and were identified tentatively by the accurate mass of quadruple-time-of-flight mass spectrometry. A total of 29 components can be used as the chemical markers for discrimination of CPA and CPC. Of them, phellodenrine is significantly higher in CPC than that of CPA, whereas obacunone and obaculactone are significantly higher in CPA than that of CPC. The present study proves that multivariate analysis approach based chemical analysis greatly contributes to the investigation of CPA and CPC, and showed that the identified chemical markers as a whole should be used to discriminate the two herbal medicines, and simultaneously the results also provided chemical information for their quality assessment. Multivariate analysis approach was performed to the investigate the herbal medicineThe chemical markers were identified through multivariate analysis approachA total of 29 components can be used as the chemical markers. UPLC-Q/TOF-MS-based multivariate analysis method for the herbal medicine samples Abbreviations used: CPC: Cortex Phellodendri chinensis, CPA: Cortex Phellodendri amurensis, PCA: Principal component analysis, OPLS-DA: Orthogonal partial least squares discriminant analysis, BPI: Base peaks ion intensity.

  20. Petroleomics: the next grand challenge for chemical analysis.

    PubMed

    Marshall, Alan G; Rodgers, Ryan P

    2004-01-01

    Ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry has recently revealed that petroleum crude oil contains heteroatom-containing (N,O,S) organic components having more than 20,000 distinct elemental compositions (C(c)H(h)N(n)O(o)S(s)). It is therefore now possible to contemplate the ultimate characterization of all of the chemical constituents of petroleum, along with their interactions and reactivity, a concept we denote as "petroleomics". Such knowledge has already proved capable of distinguishing petroleum and its distillates according to their geochemical origin and maturity, distillation cut, extraction method, catalytic processing, etc. The key features that have opened up this new field have been (a) ultrahigh-resolution FT-ICR mass analysis, specifically, the capability to resolve species differing in elemental composition by C(3) vs SH(4) (i.e., 0.0034 Da); (b) higher magnetic field to cover the whole mass range at once; (c) dynamic range extension by external mass filtering; and (d) plots of Kendrick mass defect vs nominal Kendrick mass as a means for sorting different compound "classes" (i.e., numbers of N, O, and S atoms), "types" (rings plus double bonds), and alkylation ((-CH(2))(n)) distributions, thereby extending to >900 Da the upper limit for unique assignment of elemental composition based on accurate mass measurement. The same methods are also being applied successfully to analysis of humic and fulvic acids, coals, and other complex natural mixtures, often without prior or on-line chromatographic separation.

  1. Environmental analysis of the chemical release module. [space shuttle payload

    NASA Technical Reports Server (NTRS)

    Heppner, J. P.; Dubin, M.

    1980-01-01

    The environmental analysis of the Chemical Release Module (a free flying spacecraft deployed from the space shuttle to perform chemical release experiments) is reviewed. Considerations of possible effects of the injectants on human health, ionosphere, weather, ground based optical astronomical observations, and satellite operations are included. It is concluded that no deleterious environmental effects of widespread or long lasting nature are anticipated from chemical releases in the upper atmosphere of the type indicated for the program.

  2. A broadleaf species enhances an autotoxic conifers growth through belowground chemical interactions.

    PubMed

    Xia, Zhi-Chao; Kong, Chui-Hua; Chen, Long-Chi; Wang, Peng; Wang, Si-Long

    2016-09-01

    Plants may affect the performance of neighboring plants either positively or negatively through interspecific and intraspecific interactions. Productivity of mixed-species systems is ultimately the net result of positive and negative interactions among the component species. Despite increasing knowledge of positive interactions occurring in mixed-species tree systems, relatively little is known about the mechanisms underlying such interactions. Based on data from 25-year-old experimental stands in situ and a series of controlled experiments, we test the hypothesis that a broadleaf, non-N fixing species, Michelia macclurei, facilitates the performance of an autotoxic conifer Chinese fir (Cunninghamia lanceolata) through belowground chemical interactions. Chinese fir roots released the allelochemical cyclic dipeptide (6-hydroxy-1,3-dimethyl-8-nonadecyl-[1,4]-diazocane- 2,5-diketone) into the soil environment, resulting in self-growth inhibition, and deterioration of soil microorganisms that improve P availability. However, when grown with M. macclurei the growth of Chinese fir was consistently enhanced. In particular, Chinese fir enhanced root growth and distribution in deep soil layers. When compared with monocultures of Chinese fir, the presence of M. macclurei reduced release and increased degradation of cyclic dipeptide in the soil, resulting in a shift from self-inhibition to chemical facilitation. This association also improved the soil microbial community by increasing arbuscular mycorrhizal fungi, and induced the production of Chinese fir roots. We conclude that interspecific interactions are less negative than intraspecific ones between non-N fixing broadleaf and autotoxic conifer species. The impacts are generated by reducing allelochemical levels, enhancing belowground mutualisms, improving soil properties, and changing root distributions as well as the net effects of all the processes within the soil. In particular, allelochemical context alters the

  3. Chemical composition and fuel wood characteristics of fast growing tree species in India

    NASA Astrophysics Data System (ADS)

    Chauhan, S. K.; Soni, R.

    2012-04-01

    India is one of the growing economy in the world and energy is a critical input to sustain the growth of development. Country aims at security and efficiency of energy. Though fossil fuel will continue to play a dominant role in energy scenario but country is committed to global environmental well being thus stressing on environment friendly technologies. Concerns of energy security in this changing climatic situation have led to increasing support for the development of new renewable source of energy. Government though is determined to facilitate bio-energy and many projects have been established but initial after-affects more specifically on the domestic fuelwood are evident. Even the biomass power generating units are facing biomass crisis and accordingly the prices are going up. The CDM projects are supporting the viability of these units resultantly the Indian basket has a large number of biomass projects (144 out of total 506 with 28 per cent CERs). The use for fuelwood as a primary source of energy for domestic purpose by the poor people (approx. 80 per cent) and establishment of bio-energy plants may lead to deforestation to a great extent and only solution to this dilemma is to shift the wood harvest from the natural forests to energy plantations. However, there is conspicuous lack of knowledge with regards to the fuelwood characteristics of fast growing tree species for their selection for energy plantations. The calorific value of the species is important criteria for selection for fuel but it is affected by the proportions of biochemical constituents present in them. The aim of the present work was to study the biomass production, calorific value and chemical composition of different short rotation tree species. The study was done from the perspective of using the fast growing tree species for energy production at short rotation and the study concluded that short rotation tree species like Gmelina arborea, Eucalyptus tereticornis, Pongamia pinnata

  4. High Throughput Ambient Mass Spectrometric Approach to Species Identification and Classification from Chemical Fingerprint Signatures

    DOE PAGES

    Musah, Rabi A.; Espinoza, Edgard O.; Cody, Robert B.; ...

    2015-07-09

    A high throughput method for species identification and classification through chemometric processing of direct analysis in real time (DART) mass spectrometry-derived fingerprint signatures has been developed. The method entails introduction of samples to the open air space between the DART ion source and the mass spectrometer inlet, with the entire observed mass spectral fingerprint subjected to unsupervised hierarchical clustering processing. Moreover, a range of both polar and non-polar chemotypes are instantaneously detected. The result is identification and species level classification based on the entire DART-MS spectrum. In this paper, we illustrate how the method can be used to: (1) distinguishmore » between endangered woods regulated by the Convention for the International Trade of Endangered Flora and Fauna (CITES) treaty; (2) assess the origin and by extension the properties of biodiesel feedstocks; (3) determine insect species from analysis of puparial casings; (4) distinguish between psychoactive plants products; and (5) differentiate between Eucalyptus species. An advantage of the hierarchical clustering approach to processing of the DART-MS derived fingerprint is that it shows both similarities and differences between species based on their chemotypes. Furthermore, full knowledge of the identities of the constituents contained within the small molecule profile of analyzed samples is not required.« less

  5. High Throughput Ambient Mass Spectrometric Approach to Species Identification and Classification from Chemical Fingerprint Signatures

    SciTech Connect

    Musah, Rabi A.; Espinoza, Edgard O.; Cody, Robert B.; Lesiak, Ashton D.; Christensen, Earl D.; Moore, Hannah E.; Maleknia, Simin; Drijhout, Falko P.

    2015-07-09

    A high throughput method for species identification and classification through chemometric processing of direct analysis in real time (DART) mass spectrometry-derived fingerprint signatures has been developed. The method entails introduction of samples to the open air space between the DART ion source and the mass spectrometer inlet, with the entire observed mass spectral fingerprint subjected to unsupervised hierarchical clustering processing. Moreover, a range of both polar and non-polar chemotypes are instantaneously detected. The result is identification and species level classification based on the entire DART-MS spectrum. In this paper, we illustrate how the method can be used to: (1) distinguish between endangered woods regulated by the Convention for the International Trade of Endangered Flora and Fauna (CITES) treaty; (2) assess the origin and by extension the properties of biodiesel feedstocks; (3) determine insect species from analysis of puparial casings; (4) distinguish between psychoactive plants products; and (5) differentiate between Eucalyptus species. An advantage of the hierarchical clustering approach to processing of the DART-MS derived fingerprint is that it shows both similarities and differences between species based on their chemotypes. Furthermore, full knowledge of the identities of the constituents contained within the small molecule profile of analyzed samples is not required.

  6. A High Throughput Ambient Mass Spectrometric Approach to Species Identification and Classification from Chemical Fingerprint Signatures

    NASA Astrophysics Data System (ADS)

    Musah, Rabi A.; Espinoza, Edgard O.; Cody, Robert B.; Lesiak, Ashton D.; Christensen, Earl D.; Moore, Hannah E.; Maleknia, Simin; Drijfhout, Falko P.

    2015-07-01

    A high throughput method for species identification and classification through chemometric processing of direct analysis in real time (DART) mass spectrometry-derived fingerprint signatures has been developed. The method entails introduction of samples to the open air space between the DART ion source and the mass spectrometer inlet, with the entire observed mass spectral fingerprint subjected to unsupervised hierarchical clustering processing. A range of both polar and non-polar chemotypes are instantaneously detected. The result is identification and species level classification based on the entire DART-MS spectrum. Here, we illustrate how the method can be used to: (1) distinguish between endangered woods regulated by the Convention for the International Trade of Endangered Flora and Fauna (CITES) treaty; (2) assess the origin and by extension the properties of biodiesel feedstocks; (3) determine insect species from analysis of puparial casings; (4) distinguish between psychoactive plants products; and (5) differentiate between Eucalyptus species. An advantage of the hierarchical clustering approach to processing of the DART-MS derived fingerprint is that it shows both similarities and differences between species based on their chemotypes. Furthermore, full knowledge of the identities of the constituents contained within the small molecule profile of analyzed samples is not required.

  7. A High Throughput Ambient Mass Spectrometric Approach to Species Identification and Classification from Chemical Fingerprint Signatures

    PubMed Central

    Musah, Rabi A.; Espinoza, Edgard O.; Cody, Robert B.; Lesiak, Ashton D.; Christensen, Earl D.; Moore, Hannah E.; Maleknia, Simin; Drijfhout, Falko P.

    2015-01-01

    A high throughput method for species identification and classification through chemometric processing of direct analysis in real time (DART) mass spectrometry-derived fingerprint signatures has been developed. The method entails introduction of samples to the open air space between the DART ion source and the mass spectrometer inlet, with the entire observed mass spectral fingerprint subjected to unsupervised hierarchical clustering processing. A range of both polar and non-polar chemotypes are instantaneously detected. The result is identification and species level classification based on the entire DART-MS spectrum. Here, we illustrate how the method can be used to: (1) distinguish between endangered woods regulated by the Convention for the International Trade of Endangered Flora and Fauna (CITES) treaty; (2) assess the origin and by extension the properties of biodiesel feedstocks; (3) determine insect species from analysis of puparial casings; (4) distinguish between psychoactive plants products; and (5) differentiate between Eucalyptus species. An advantage of the hierarchical clustering approach to processing of the DART-MS derived fingerprint is that it shows both similarities and differences between species based on their chemotypes. Furthermore, full knowledge of the identities of the constituents contained within the small molecule profile of analyzed samples is not required. PMID:26156000

  8. Theory, Image Simulation, and Data Analysis of Chemical Release Experiments

    NASA Technical Reports Server (NTRS)

    Wescott, Eugene M.

    1994-01-01

    The final phase of Grant NAG6-1 involved analysis of physics of chemical releases in the upper atmosphere and analysis of data obtained on previous NASA sponsored chemical release rocket experiments. Several lines of investigation of past chemical release experiments and computer simulations have been proceeding in parallel. This report summarizes the work performed and the resulting publications. The following topics are addressed: analysis of the 1987 Greenland rocket experiments; calculation of emission rates for barium, strontium, and calcium; the CRIT 1 and 2 experiments (Collisional Ionization Cross Section experiments); image calibration using background stars; rapid ray motions in ionospheric plasma clouds; and the NOONCUSP rocket experiments.

  9. Theory, Image Simulation, and Data Analysis of Chemical Release Experiments

    SciTech Connect

    Wescott, E.M.

    1994-04-01

    The final phase of Grant NAG6-1 involved analysis of physics of chemical releases in the upper atmosphere and analysis of data obtained on previous NASA sponsored chemical release rocket experiments. Several lines of investigation of past chemical release experiments and computer simulations have been proceeding in parallel. This report summarizes the work performed and the resulting publications. The following topics are addressed: analysis of the 1987 Greenland rocket experiments; calculation of emission rates for barium, strontium, and calcium; the CRIT 1 and 2 experiments (Collisional Ionization Cross Section experiments); image calibration using background stars; rapid ray motions in ionospheric plasma clouds; and the NOONCUSP rocket experiments.

  10. Valorization of By-Products from Commercial Fish Species: Extraction and Chemical Properties of Skin Gelatins.

    PubMed

    Sousa, Sérgio C; Vázquez, José A; Pérez-Martín, Ricardo I; Carvalho, Ana P; Gomes, Ana M

    2017-09-14

    Fish skins constitute an important fraction of the enormous amount of wastes produced by the fish processing industry, part of which may be valorized through the extraction of gelatins. This research exploited the extraction and characterization of gelatins from the skin of three seawater fish species, namely yellowfin tuna (Thunnus albacares), blue shark (Prionace glauca), and greenland halibut (Reinhardtius hippoglossoides). Characterization included chemical composition, rheology, structure, texture, and molecular weight, whereas extraction studies intended to reduce costly steps during extraction process (reagents concentration, water consumption, and time of processing), while maintaining extraction efficiency. Chemical and physical characterization of the obtained gelatins revealed that the species from which the gelatin was extracted, as well as the heat treatment used, were key parameters in order to obtain a final product with specific properties. Therefore, the extraction conditions selected during gelatin production will drive its utilization into markets with well-defined specifications, where the necessity of unique products is being claimed. Such achievements are of utmost importance to the food industry, by paving the way to the introduction in the market of gelatins with distinct rheological and textural properties, which enables them to enlarge their range of applications.

  11. Recognizing chemicals in patents: a comparative analysis.

    PubMed

    Habibi, Maryam; Wiegandt, David Luis; Schmedding, Florian; Leser, Ulf

    2016-01-01

    Recently, methods for Chemical Named Entity Recognition (NER) have gained substantial interest, driven by the need for automatically analyzing todays ever growing collections of biomedical text. Chemical NER for patents is particularly essential due to the high economic importance of pharmaceutical findings. However, NER on patents has essentially been neglected by the research community for long, mostly because of the lack of enough annotated corpora. A recent international competition specifically targeted this task, but evaluated tools only on gold standard patent abstracts instead of full patents; furthermore, results from such competitions are often difficult to extrapolate to real-life settings due to the relatively high homogeneity of training and test data. Here, we evaluate the two state-of-the-art chemical NER tools, tmChem and ChemSpot, on four different annotated patent corpora, two of which consist of full texts. We study the overall performance of the tools, compare their results at the instance level, report on high-recall and high-precision ensembles, and perform cross-corpus and intra-corpus evaluations. Our findings indicate that full patents are considerably harder to analyze than patent abstracts and clearly confirm the common wisdom that using the same text genre (patent vs. scientific) and text type (abstract vs. full text) for training and testing is a pre-requisite for achieving high quality text mining results.

  12. Global nutritional profiling for mutant and chemical mode-of-action analysis in filamentous fungi.

    PubMed

    Tanzer, Matthew M; Arst, Herbert N; Skalchunes, Amy R; Coffin, Marie; Darveaux, Blaise A; Heiniger, Ryan W; Shuster, Jeffrey R

    2003-12-01

    We describe a method for gene function discovery and chemical mode-of-action analysis via nutrient utilization using a high throughput Nutritional Profiling platform suitable for filamentous microorganisms. We have optimized the growth conditions for each fungal species to produce reproducible optical density growth measurements in microtiter plates. We validated the Nutritional Profiling platform using a nitrogen source utilization assay to analyze 21 Aspergillus nidulans strains with mutations in the master nitrogen regulatory gene, areA. Analysis of these data accurately reproduced expected results and provided new data to demonstrate that this platform is suitable for fine level phenotyping of filamentous fungi. Next, we analyzed the differential responses of two fungal species to a glutamine synthetase inhibitor, illustrating chemical mode-of-action analysis. Finally, a comparative phenotypic study was performed to characterize carbon catabolite repression in four fungal species using a carbon source utilization assay. The results demonstrate differentiation between two Aspergillus species and two diverse plant pathogens and provide a wealth of new data on fungal nutrient utilization. Thus, these assays can be used for gene function and chemical mode-of-action analysis at the whole organism level as well as interspecies comparisons in a variety of filamentous fungi. Additionally, because uniform distribution of growth within wells is maintained, comparisons between yeast and filamentous forms of a single organism can be performed.

  13. Modular verification of chemical reaction network encodings via serializability analysis

    PubMed Central

    Lakin, Matthew R.; Stefanovic, Darko; Phillips, Andrew

    2015-01-01

    Chemical reaction networks are a powerful means of specifying the intended behaviour of synthetic biochemical systems. A high-level formal specification, expressed as a chemical reaction network, may be compiled into a lower-level encoding, which can be directly implemented in wet chemistry and may itself be expressed as a chemical reaction network. Here we present conditions under which a lower-level encoding correctly emulates the sequential dynamics of a high-level chemical reaction network. We require that encodings are transactional, such that their execution is divided by a “commit reaction” that irreversibly separates the reactant-consuming phase of the encoding from the product-generating phase. We also impose restrictions on the sharing of species between reaction encodings, based on a notion of “extra tolerance”, which defines species that may be shared between encodings without enabling unwanted reactions. Our notion of correctness is serializability of interleaved reaction encodings, and if all reaction encodings satisfy our correctness properties then we can infer that the global dynamics of the system are correct. This allows us to infer correctness of any system constructed using verified encodings. As an example, we show how this approach may be used to verify two- and four-domain DNA strand displacement encodings of chemical reaction networks, and we generalize our result to the limit where the populations of helper species are unlimited. PMID:27325906

  14. Modular verification of chemical reaction network encodings via serializability analysis.

    PubMed

    Lakin, Matthew R; Stefanovic, Darko; Phillips, Andrew

    2016-06-13

    Chemical reaction networks are a powerful means of specifying the intended behaviour of synthetic biochemical systems. A high-level formal specification, expressed as a chemical reaction network, may be compiled into a lower-level encoding, which can be directly implemented in wet chemistry and may itself be expressed as a chemical reaction network. Here we present conditions under which a lower-level encoding correctly emulates the sequential dynamics of a high-level chemical reaction network. We require that encodings are transactional, such that their execution is divided by a "commit reaction" that irreversibly separates the reactant-consuming phase of the encoding from the product-generating phase. We also impose restrictions on the sharing of species between reaction encodings, based on a notion of "extra tolerance", which defines species that may be shared between encodings without enabling unwanted reactions. Our notion of correctness is serializability of interleaved reaction encodings, and if all reaction encodings satisfy our correctness properties then we can infer that the global dynamics of the system are correct. This allows us to infer correctness of any system constructed using verified encodings. As an example, we show how this approach may be used to verify two- and four-domain DNA strand displacement encodings of chemical reaction networks, and we generalize our result to the limit where the populations of helper species are unlimited.

  15. Genetic diversity analysis in Piper species (Piperaceae) using RAPD markers.

    PubMed

    Sen, Sandeep; Skaria, Reby; Abdul Muneer, P M

    2010-09-01

    The genetic diversity of eight species of Piper (Piperaceae) viz., P. nigrum, P. longum, P. betle, P. chaba, P. argyrophyllum, P. trichostachyon, P. galeatum, and P. hymenophyllum from Kerala state, India were analyzed by Random amplified polymorphic DNA (RAPD). Out of 22 10-mer RAPD primers screened, 11 were selected for comparative analysis of different species of Piper. High genetic variations were found among different Piper species studied. Among the total of 149 RAPD fragments amplified, 12 bands (8.05%) were found monomorphic in eight species. The remaining 137 fragments were found polymorphic (91.95%). Species-specific bands were found in all eight species studied. The average gene diversity or heterozygosity (H) was 0.33 across all the species, genetic distances ranged from 0.21 to 0.69. The results of this study will facilitate germplasm identification, management, and conservation.

  16. Chemical analysis of exhaled human breath using a terahertz spectroscopic approach

    NASA Astrophysics Data System (ADS)

    Fosnight, Alyssa M.; Moran, Benjamin L.; Medvedev, Ivan R.

    2013-09-01

    As many as 3500 chemicals are reported in exhaled human breath. Many of these chemicals are linked to certain health conditions and environmental exposures. This experiment demonstrated a method of breath analysis utilizing a high resolution spectroscopic technique for the detection of ethanol, methanol, and acetone in the exhaled breath of a person who consumed alcohol. This technique is applicable to a wide range of polar molecules. For select species, unambiguous detection in a part per trillion dilution range with a total sample size in a femtomol range is feasible. It compares favorably with other methods of breath analysis.

  17. Alpha particle backscattering measurements used for chemical analysis of surfaces

    NASA Technical Reports Server (NTRS)

    Patterson, J. H.

    1967-01-01

    Alpha particle backscattering performs a chemical analysis of surfaces. The apparatus uses a curium source and a semiconductor detector to determine the energy spectrum of the particles. This in turn determines the chemical composition of the surface after calibration to known samples.

  18. Chemical properties and methods of analysis of refractory compounds

    NASA Technical Reports Server (NTRS)

    Samsonov, G. V. (Editor); Frantsevich, I. N. (Editor); Yeremenko, V. N. (Editor); Nazarchuk, T. N. (Editor); Popova, O. I. (Editor)

    1978-01-01

    Reactions involving refractory metals and the alloys based on them are discussed. Chemical, electrochemical, photometric, spectrophotometric, and X-ray analysis are among the methods described for analyzing the results of the reactions and for determining the chemical properties of these materials.

  19. Chemical Biology of Hydropersulfides and Related Species: Possible Roles in Cellular Protection and Redox Signaling.

    PubMed

    Álvarez, Lucía; Bianco, Christopher L; Toscano, John P; Lin, Joseph; Akaike, Takaaki; Fukuto, Jon M

    2017-10-01

    For >20 years, physiological signaling associated with the endogenous generation of hydrogen sulfide (H2S) has been of significant interest. Despite its presumed importance, the biochemical mechanisms associated with its actions have not been elucidated. Recent Advances: Recently it has been found that H2S-related or derived species are highly prevalent in mammalian systems and that these species may be responsible for some, if not the majority, of the biological actions attributed to H2S. One of the most prevalent and intriguing species are hydropersulfides (RSSH), which can be present at significant levels. Indeed, it appears that H2S and RSSH are intimately linked in biological systems and likely to be mutually inclusive. The fact that H2S and polysulfides such as RSSH are present simultaneously means that the biological actions previously assigned to H2S can be instead because of the presence of RSSH (or other polysulfides). Thus, it remains possible that hydropersulfides are the biological effectors, and H2S serves, to a certain extent, as a marker for persulfides and polysulfides. Addressing this possibility will to a large extent be based on the chemistry of these species. Currently, it is known that persulfides possess unique and novel chemical properties that may explain their biological prevalence. However, significantly more work will be required to establish the possible physiological roles of these species. Moreover, an understanding of the regulation of their biosynthesis and degradation will become important topics in piecing together their biology. Antioxid. Redox Signal. 00, 000-000.

  20. Variation in sensitivity of aquatic species to toxicants: Practical consequences for effect assessment of chemical substances

    SciTech Connect

    Vaal, M.A.; Van Leeuwen, C.J.; Hoekstra, J.A.; Hermens, J.L.M.

    2000-04-01

    This study addresses the relation between the sensitivity of aquatic species and mode of action of different classes or organic chemicals. The authors analyzed large data sets of ecotoxicological information to reveal the interspecies variation in sensitivity, to relate this variation to the compounds' mode of action, and to explain the observed patterns using general biological information. Here the authors present a general framework and recommendations for risk assessment procedures. The authors recommend the use of toxicologically based classification schemes at an early stage of the risk assessment procedure. Screening programs are most efficiently run when only one species per compound is tested to prioritize substances. The toxicity of compounds belonging to the class of nonpolar narcotics is highly predictable and shows little interspecies variation. For these compounds quantitative structure-activity relationships (WSARs) can be used to estimate effect levels. Most effort should be put into testing reactive compounds and compounds with a specific mode of action as toxicity to some species can be 10{sup 5}--10{sup 6} times higher compared with less sensitive species. The use of assessment factors in effect assessment procedures may lead to an underestimation of effects on the more sensitive species. For many priority pollutants there is little information on their ecotoxicity. Predictive techniques are needed to compensate for this lack of data. Knowledge of the relation between modes of action of compounds and interspecies variation in sensitivity should be integrated in risk assessment procedures in order to make more efficient use of the limited financial resources available.

  1. Chemical composition and antibacterial activities of seven Eucalyptus species essential oils leaves.

    PubMed

    Sebei, Khaled; Sakouhi, Fawzi; Herchi, Wahid; Khouja, Mohamed Larbi; Boukhchina, Sadok

    2015-01-19

    In this paper, we have studied the essential oils chemical composition of the leaves of seven Eucalyptus species developed in Tunisia. Eucalyptus leaves were picked from trees growing in different arboretums in Tunisia. Choucha and Mrifeg arboretums located in Sedjnene, region of Bizerte (Choucha: E. maideni, E. astrengens et E. cinerea; Mrifeg : E. leucoxylon), Korbous arboretums located in the region of Nabeul, North East Tunisia with sub-humid bioclimate, (E. lehmani), Souiniet-Ain Drahem arboretum located in region of Jendouba (E. sideroxylon, E. bicostata). Essential oils were individually tested against a large panel of microorganisms including Staphylococcus aureus (ATCC 6539), Escherichia coli (ATCC 25922), Enterococcus faecalis (ATCC29212), Listeria ivanovii (RBL 30), Bacillus cereus (ATCC11778). The yield of essential oils ranged from 1.2% to 3% (w/w) for the different Eucalyptus species. All essential oils contain α-pinene, 1,8-cineol and pinocarveol-trans for all Eucalyptus species studied. The 1,8-cineol was the major compound in all species (49.07 to 83.59%). Diameter of inhibition zone of essential oils of Eucalyptus species varied from 10 to 29 mm. The largest zone of inhibition was obtained for Bacillus cereus (E. astrengens) and the lowest for Staphylococcus aureus (E. cinerea). The essential oils from E. maideni, E. astrengens, E. cinerea (arboretum of Bizerte), E. bicostata (arboretum of Aindraham) showed the highest antibacterial activity against Listeria ivanovii and Bacillus cereus. The major constituents of Eucalyptus leaves essential oils are 1,8-cineol (49.07 to 83.59%) and α-pinene (1.27 to 26.35%). The essential oils from E. maideni, E. astrengens, E. cinerea, E. bicostata showed the highest antibacterial activity against Listeria ivanovii and Bacillus cereus, they may have potential applications in food and pharmaceutical products.

  2. Bioaccessibility of selenium after human ingestion in relation to its chemical species and compartmentalization in maize.

    PubMed

    Mombo, Stéphane; Schreck, Eva; Dumat, Camille; Laplanche, Christophe; Pierart, Antoine; Longchamp, Mélanie; Besson, Philippe; Castrec-Rouelle, Maryse

    2016-06-01

    Selenium is a micronutrient needed by all living organisms including humans, but often present in low concentration in food with possible deficiency. From another side, at higher concentrations in soils as observed in seleniferous regions of the world, and in function of its chemical species, Se can also induce (eco)toxicity. Root Se uptake was therefore studied in function of its initial form for maize (Zea mays L.), a plant widely cultivated for human and animal food over the world. Se phytotoxicity and compartmentalization were studied in different aerial plant tissues. For the first time, Se oral human bioaccessibility after ingestion was assessed for the main Se species (Se(IV) and Se(VI)) with the BARGE ex vivo test in maize seeds (consumed by humans), and in stems and leaves consumed by animals. Corn seedlings were cultivated in hydroponic conditions supplemented with 1 mg L(-1) of selenium (Se(IV), Se(VI), Control) for 4 months. Biomass, Se concentration, and bioaccessibility were measured on harvested plants. A reduction in plant biomass was observed under Se treatments compared to control, suggesting its phytotoxicity. This plant biomass reduction was higher for selenite species than selenate, and seed was the main affected compartment compared to control. Selenium compartmentalization study showed that for selenate species, a preferential accumulation was observed in leaves, whereas selenite translocation was very limited toward maize aerial parts, except in the seeds where selenite concentrations are generally high. Selenium oral bioaccessibility after ingestion fluctuated from 49 to 89 % according to the considered plant tissue and Se species. Whatever the tissue, selenate appeared as the most human bioaccessible form. A potential Se toxicity was highlighted for people living in seleniferous regions, this risk being enhanced by the high Se bioaccessibility.

  3. Impact of Environmentally Based Chemical Hardness on Uranium Speciation and Toxicity in Six Aquatic Species

    PubMed Central

    Goulet, Richard R; Thompson, Patsy A; Serben, Kerrie C; Eickhoff, Curtis V

    2015-01-01

    Treated effluent discharge from uranium (U) mines and mills elevates the concentrations of U, calcium (Ca), magnesium (Mg), and sulfate (SO42–) above natural levels in receiving waters. Many investigations on the effect of hardness on U toxicity have been experiments on the combined effects of changes in hardness, pH, and alkalinity, which do not represent water chemistry downstream of U mines and mills. Therefore, more toxicity studies with water chemistry encountered downstream of U mines and mills are necessary to support predictive assessments of impacts of U discharge to the environment. Acute and chronic U toxicity laboratory bioassays were realized with 6 freshwater species in waters of low alkalinity, circumneutral pH, and a range of chemical hardness as found in field samples collected downstream of U mines and mills. In laboratory-tested waters, speciation calculations suggested that free uranyl ion concentrations remained constant despite increasing chemical hardness. When hardness increased while pH remained circumneutral and alkalinity low, U toxicity decreased only to Hyalella azteca and Pseudokirchneriella subcapitata. Also, Ca and Mg did not compete with U for the same uptake sites. The present study confirms that the majority of studies concluding that hardness affected U toxicity were in fact studies in which alkalinity and pH were the stronger influence. The results thus confirm that studies predicting impacts of U downstream of mines and mills should not consider chemical hardness. PMID:25475484

  4. Rapid discrimination between four seagrass species using hybrid analysis.

    PubMed

    Osathanunkul, M; Madesis, P; Ounjai, S; Suwannapoom, C; Jampeetong, A

    2015-04-27

    Biological species are traditionally identified based on their morphological features and the correct identification of species is critical in biological studies. However, some plant types, such as seagrass, are taxonomically problematic and difficult to identify. Furthermore, closely related seagrass species, such as Halophila spp, form a taxonomically unresolved complex. Although some seagrass taxa are easy to recognize, most species are difficult to identify without skilled taxonomic or molecular techniques. Barcoding coupled with High Resolution Melting analysis (BAR-HRM) offers a potentially reliable, rapid, and cost-effective method to confirm species. Here, DNA information of two chloroplast loci was used in combination with HRM analysis to discriminate four species of seagrass collected off the southern coast of Thailand. A distinct melting curve presenting one inflection point was generated for each species using rbcL primers. While the melting profiles of Cymodocea rotundata and Cymodocea serrulata were not statistically different, analysis of the normalized HRM curves produced with the rpoC primers allowed for their discrimination. The Bar-HRM technique showed promise in discriminating seagrass species and with further adaptations and improvements, could make for an effective and power tool for confirming seagrass species.

  5. Why species tell more about traits than traits about species: predictive analysis.

    PubMed

    Clark, James S

    2016-08-01

    Trait analysis aims to understand relationships between traits, species diversity, and the environment. Current methods could benefit from a model-based probabilistic framework that accommodates covariance between traits and quantifies contributions from inherent trait syndromes, species interactions, and responses to the environment. I develop a model-based approach that separates these effects on trait diversity. Application to USDA Forest Inventory and Analysis (FIA) data in the eastern United States demonstrates an apparent paradox, that the analysis of species better explains and predicts traits than does direct analysis of the traits themselves; trait data contain less, not more, information than species on environmental responses. Whereas variation in some traits is dominated by inherent syndromes (tendency for certain traits to be associated with others within an individual and species), others are strongly controlled by variation in species diversity. There is substantial variation in environmental control on trait patterns, between traits and regionally. In terms of environmental response traits do not aggregate into defined plant functional types, as would be desirable for models.

  6. A cell-free testing platform to screen chemicals of potential neurotoxic concern across twenty vertebrate species.

    PubMed

    Arini, Adeline; Mittal, Krittika; Dornbos, Peter; Head, Jessica; Rutkiewicz, Jennifer; Basu, Niladri

    2017-06-08

    There is global demand for new in vitro testing tools for ecological risk assessment. The objective of the present study was to apply a set of cell-free neurochemical assays to screen many chemicals across many species in a relatively high-throughput manner. The platform assessed 7 receptors and enzymes that mediate neurotransmission of γ-aminobutyric acid, dopamine, glutamate, and acetylcholine. Each assay was optimized to work across 20 vertebrate species (5 fish, 5 birds, 7 mammalian wildlife, 3 biomedical species including humans). We tested the screening assay platform against 80 chemicals (23 pharmaceuticals and personal care products, 20 metal[loid]s, 22 polycyclic aromatic hydrocarbons and halogenated organic compounds, 15 pesticides). In total, 10 800 species-chemical-assay combinations were tested, and significant differences were found in 4041 cases. All 7 assays were significantly affected by at least one chemical in each species tested. Among the 80 chemicals tested, nearly all resulted in a significant impact on at least one species and one assay. The 5 most active chemicals were prochloraz, HgCl2 , Sn, benzo[a]pyrene, and vinclozolin. Clustering analyses revealed groupings according to chemicals, species, and chemical-assay combinations. The results show that cell-free assays can screen a large number of samples in a short period of time in a cost-effective manner in a range of animals not easily studied using traditional approaches. Strengths and limitations of this approach are discussed, as well as next steps. Environ Toxicol Chem 2017;9999:1-10. © 2017 SETAC. © 2017 SETAC.

  7. Exergy analysis of a chemical metallurgical process

    NASA Astrophysics Data System (ADS)

    Morris, D. R.; Steward, F. R.

    1984-12-01

    The concept of available work or exergy is used to develop an expression from which the causes of exergy losses in a chemical reactor are identified. The concept is illustrated by application to a lead blast furnace. The performance of the sinter plant and the lead smelter are assessed by the same procedures. The possibilities of exergy recovery are discussed and a heat pump installation is described. The advantages of the exergy method of process assessment relative to the traditional heat balance are discussed.

  8. Five chemically rich species of tropical marine cyanobacteria of the genus Okeania gen. nov. (Oscillatoriales, Cyanoprokaryota).

    PubMed

    Engene, Niclas; Paul, Valerie J; Byrum, Tara; Gerwick, William H; Thor, Andrea; Ellisman, Mark H

    2013-12-01

    An adverse consequence of applying morphology-based taxonomic systems to catalog cyanobacteria, which generally are limited in the number of available morphological characters, is a fundamental underestimation of natural biodiversity. In this study, we further dissect the polyphyletic cyanobacterial genus Lyngbya and delineate the new genus Okeania gen. nov. Okeania is a tropical and subtropical, globally distributed marine group abundant in the shallow-water benthos. Members of Okeania are of considerable ecological and biomedical importance because specimens within this group biosynthesize biologically active secondary metabolites and are known to form blooms in coastal benthic environments. Herein, we describe five species of the genus Okeania: O. hirsuta (type species of the genus), O. plumata, O. lorea, O. erythroflocculosa, and O. comitata, under the provisions of the International Code of Nomenclature for Algae, Fungi, and Plants. All five Okeania species were morphologically, phylogenetically, and chemically distinct. This investigation provides a classification system that is able to identify Okeania spp. and predict their production of bioactive secondary metabolites.

  9. Snake (Colubridae: Thamnophis) predatory responses to chemical cues from native and introduced prey species

    USGS Publications Warehouse

    Mullin, S.J.; Imbert, H.; Fish, J.M.; Ervin, E.L.; Fisher, R.N.

    2004-01-01

    Several aquatic vertebrates have been introduced into freshwater systems in California over the past 100 years. Some populations of the two-striped garter snake (Thamnophis hammondii) have lived in sympatry with these species since their introduction; other populations have never encountered them. To assess the possible adaptation to a novel prey, we tested the predatory responses of T. hammondii from different populations to different chemosensory cues from native and introduced prey species. We presented chemical extracts from potential prey types and 2 control odors to individual snakes on cotton swabs and recorded the number of tongue flicks and attacks directed at each swab. Subject response was higher for prey odors than control substances. Odors from introduced centrarchid fish (Lepomis) elicited higher response levels than other prey types, including native anuran larvae (Pseudacris regilla). The pattern of response was similar for both populations of snakes (experienced and nai??ve, with respect to the introduced prey). We suggest that the generalist aquatic lifestyle of T. hammondii has allowed it to take advantage of increasing populations of introduced prey. Decisions on the management strategies for some of these introduced prey species should include consideration of how T. hammondii populations might respond in areas of sympatry.

  10. Acoustic Aposematism and Evasive Action in Select Chemically Defended Arctiine (Lepidoptera: Erebidae) Species: Nonchalant or Not?

    PubMed

    Dowdy, Nicolas J; Conner, William E

    2016-01-01

    Tiger moths (Erebidae: Arctiinae) have experienced intense selective pressure from echolocating, insectivorous bats for over 65 million years. One outcome has been the evolution of acoustic signals that advertise the presence of toxins sequestered from the moths' larval host plants, i.e. acoustic aposematism. Little is known about the effectiveness of tiger moth anti-bat sounds in their natural environments. We used multiple infrared cameras to reconstruct bat-moth interactions in three-dimensional (3-D) space to examine how functional sound-producing organs called tymbals affect predation of two chemically defended tiger moth species: Pygarctia roseicapitis (Arctiini) and Cisthene martini (Lithosiini). P. roseicapitis and C. martini with intact tymbals were 1.8 and 1.6 times less likely to be captured by bats relative to those rendered silent. 3-D flight path and acoustic analyses indicated that bats actively avoided capturing sound-producing moths. Clicking behavior differed between the two tiger moth species, with P. roseicapitis responding in an earlier phase of bat attack. Evasive flight behavior in response to bat attacks was markedly different between the two tiger moth species. P. roseicapitis frequently paired evasive dives with aposematic sound production. C. martini were considerably more nonchalant and employed evasion in fewer interactions. Our results show that acoustic aposematism is effective at deterring bat predation in a natural context and that this strategy is likely to be the ancestral function of tymbal organs within the Arctiinae.

  11. Organic Redox Species in Aqueous Flow Batteries: Redox Potentials, Chemical Stability and Solubility

    PubMed Central

    Wedege, Kristina; Dražević, Emil; Konya, Denes; Bentien, Anders

    2016-01-01

    Organic molecules are currently investigated as redox species for aqueous low-cost redox flow batteries (RFBs). The envisioned features of using organic redox species are low cost and increased flexibility with respect to tailoring redox potential and solubility from molecular engineering of side groups on the organic redox-active species. In this paper 33, mainly quinone-based, compounds are studied experimentially in terms of pH dependent redox potential, solubility and stability, combined with single cell battery RFB tests on selected redox pairs. Data shows that both the solubility and redox potential are determined by the position of the side groups and only to a small extent by the number of side groups. Additionally, the chemical stability and possible degradation mechanisms leading to capacity loss over time are discussed. The main challenge for the development of all-organic RFBs is to identify a redox pair for the positive side with sufficiently high stability and redox potential that enables battery cell potentials above 1 V. PMID:27966605

  12. Acoustic Aposematism and Evasive Action in Select Chemically Defended Arctiine (Lepidoptera: Erebidae) Species: Nonchalant or Not?

    PubMed Central

    Dowdy, Nicolas J.; Conner, William E.

    2016-01-01

    Tiger moths (Erebidae: Arctiinae) have experienced intense selective pressure from echolocating, insectivorous bats for over 65 million years. One outcome has been the evolution of acoustic signals that advertise the presence of toxins sequestered from the moths’ larval host plants, i.e. acoustic aposematism. Little is known about the effectiveness of tiger moth anti-bat sounds in their natural environments. We used multiple infrared cameras to reconstruct bat-moth interactions in three-dimensional (3-D) space to examine how functional sound-producing organs called tymbals affect predation of two chemically defended tiger moth species: Pygarctia roseicapitis (Arctiini) and Cisthene martini (Lithosiini). P. roseicapitis and C. martini with intact tymbals were 1.8 and 1.6 times less likely to be captured by bats relative to those rendered silent. 3-D flight path and acoustic analyses indicated that bats actively avoided capturing sound-producing moths. Clicking behavior differed between the two tiger moth species, with P. roseicapitis responding in an earlier phase of bat attack. Evasive flight behavior in response to bat attacks was markedly different between the two tiger moth species. P. roseicapitis frequently paired evasive dives with aposematic sound production. C. martini were considerably more nonchalant and employed evasion in fewer interactions. Our results show that acoustic aposematism is effective at deterring bat predation in a natural context and that this strategy is likely to be the ancestral function of tymbal organs within the Arctiinae. PMID:27096408

  13. Organic Redox Species in Aqueous Flow Batteries: Redox Potentials, Chemical Stability and Solubility

    NASA Astrophysics Data System (ADS)

    Wedege, Kristina; Dražević, Emil; Konya, Denes; Bentien, Anders

    2016-12-01

    Organic molecules are currently investigated as redox species for aqueous low-cost redox flow batteries (RFBs). The envisioned features of using organic redox species are low cost and increased flexibility with respect to tailoring redox potential and solubility from molecular engineering of side groups on the organic redox-active species. In this paper 33, mainly quinone-based, compounds are studied experimentially in terms of pH dependent redox potential, solubility and stability, combined with single cell battery RFB tests on selected redox pairs. Data shows that both the solubility and redox potential are determined by the position of the side groups and only to a small extent by the number of side groups. Additionally, the chemical stability and possible degradation mechanisms leading to capacity loss over time are discussed. The main challenge for the development of all-organic RFBs is to identify a redox pair for the positive side with sufficiently high stability and redox potential that enables battery cell potentials above 1 V.

  14. Instrument performs nondestructive chemical analysis, data can be telemetered

    NASA Technical Reports Server (NTRS)

    Turkevich, A.

    1965-01-01

    Instrument automatically performs a nondestructive chemical analysis of surfaces and transmits the data in the form of electronic signals. It employs solid-state nuclear particle detectors with a charged nuclear particle source and an electronic pulse-height analyzer.

  15. Anatomical, chemical, and ecological factors affecting tree species choice in dendrochemistry studies

    SciTech Connect

    Cutter, B.E.; Guyette, R.P.

    1993-07-01

    Recently, element concentrations in tree rings have been used to monitor metal contamination, fertilization, and the effects of acid precipitation on soils. This has stimulated interest in which tree species may be suitable for use in studies of long-term trends in environmental chemistry. Potential radial translocation of elements across living boundaries can be a confounding factor in assessing environmental change. The selection of species which minimizes radial translocation of elements can be critical to the success of dendrochemical research. Criteria for selection of species with characteristics favorable for dendrochemical analysis are categorized into (1) habitat-based factors, (2) xylem-based factors, and (3) element-based factors. A wide geographic range and ecological amplitude provide an advantage in calibration and better controls on the effects of soil chemistry. The most important xylem-based criteria are heartwood moisture content, permeability, and the nature of the sapwood-heartwood transition. The element of interest is important in determining suitable tree species because all elements are not equally mobile or detectable in the xylem. Ideally, the tree species selected for dendrochemical study will be long-lived, grow on a wide range of sites over a large geographic distribution, have a distinct heartwood with a low number of rings in the sapwood, a low heartwood moisture content, and have low radial permeability. Recommended temperate zone North American species include white oak (Quercus alba L.), post oak (Q. stellate Wangenh.), eastern redcedar (funiperus virginiana L.), old-growth Douglas-fir [Pseudoaugu menziesii (Mirb.) Franco] and big sagebrush (Artemisia tridentata Nutt.). In addition, species such as bristlecone pine (Pinus aristata Engelm. syn. longaeva), old-growth redwood [Sequoia sempervirens (D. Don) Endl.], and giant sequoia [S. gigantea (Lindl.) Deene] may be suitable for local purposes. 118 refs., 2 tabs.

  16. Case study of the diurnal variability of chemically active species with respect to boundary layer dynamics during DOMINO

    NASA Astrophysics Data System (ADS)

    van Stratum, B. J. H.; Vilà-Guerau de Arellano, J.; Ouwersloot, H. G.; van den Dries, K.; van Laar, T. W.; Martinez, M.; Lelieveld, J.; Diesch, J.-M.; Drewnick, F.; Fischer, H.; Hosaynali Beygi, Z.; Harder, H.; Regelin, E.; Sinha, V.; Adame, J. A.; Sörgel, M.; Sander, R.; Bozem, H.; Song, W.; Williams, J.; Yassaa, N.

    2012-06-01

    We study the interactions between atmospheric boundary layer (ABL) dynamics and atmospheric chemistry using a mixed-layer model coupled to chemical reaction schemes. Guided by both atmospheric and chemical measurements obtained during the DOMINO (Diel Oxidant Mechanisms in relation to Nitrogen Oxides) campaign (2008), numerical experiments are performed to study the role of ABL dynamics and the accuracy of chemical schemes with different complexity: the Model for Ozone and Related chemical Tracers, version 4 (MOZART-4) and a reduced mechanism of this chemical system. Both schemes produce satisfactory results, indicating that the reduced scheme is capable of reproducing the O3-NOx-VOC-HOx diurnal cycle during conditions characterized by a low NOx regime and small O3 tendencies (less than 1 ppb per hour). By focusing on the budget equations of chemical species in the mixed-layer model, we show that for species like O3, NO and NO2, the influence of entrainment and boundary layer growth is of the same order as chemical production/loss. This indicates that an accurate representation of ABL processes is crucial in understanding the diel cycle of chemical species. By comparing the time scales of chemical reactive species with the mixing time scale of turbulence, we propose a classification based on the Damköhler number to further determine the importance of dynamics on chemistry during field campaigns. Our findings advocate an integrated approach, simultaneously solving the ABL dynamics and chemical reactions, in order to obtain a better understanding of chemical pathways and processes and the interpretation of the results obtained during measurement campaigns.

  17. [Chemical diversity of the biological active ingredients of salvia officinalis and some closely related species].

    PubMed

    Máthé, Imre; Hohmann, Judit; Janicsák, Gábor; Nagy, Gábor; Dora, Rédei

    2007-01-01

    Comparative studies on the volatile and non-volatile fractions of 6 species. i.e. Salvia officinalis, S. tomentosa, S. fruticosa, S. candelabrum, S. ringens, S. lavandulifolia of the Section Salvia (Lamiaceae) have been carried out. Both fractions provide the chemical pattern matches to the chemotaxonomic character of Subfamily Nepetoideae in Erdtmanr two subfamiliar system. S. lavandulifolia had the highest essential oil content, followed by S. fruticosa, S. tomentosa, S. officinalis and S. candelabrum. S. ringens contains volatile oil only in traces. The neurotoxin thujone content was the highest in the S. officinalis oils and in that of S. fruticosa. No thujone was detected in S. lavandulifolia. The other species, e.g.: S. tomentosa contain this compound only in moderate concentrations (less than 10%). Among the non-volatile fractions of the plant ingredients the triterpene ursolic and oleanolic acids had the highest concentration in the leaves. Despite some rare cases, ursolic acid dominates the tritepene fraction. Rosmarinic and caffeic acids were measured in similar concentrations, in all species. As the case of S. officinalis shows, these compounds vary significantly in all organs during the vegetation period. Caffeic acid is also ubiquitous in the genus Salvia but as our data suggest it occurs in an order of magnitude lower concentration than rosmarinic acid. The isolation of phenylethanolid martynoside, though obtained in a rather small concentration, is of great chemotaxonomic significance, as this is the first phenylethanolid type glycoside isolated not only from the Salvia genus but also from the entire Subfamily Nepetoideae. As pheylethanolids are rather common and accumulate in significant concentrations in plants of the Subfamily Lamioideae, our opinion that the chemical differences between the two subfamilies are less qualititative than quantitative, is confirmed. This holds true of other chemical markers like monoterpenes, ursolic and oleanolic

  18. Chemical preconcentrator

    DOEpatents

    Manginell, Ronald P.; Frye-Mason, Gregory C.

    2001-01-01

    A chemical preconcentrator is disclosed with applications to chemical sensing and analysis. The preconcentrator can be formed by depositing a resistive heating element (e.g. platinum) over a membrane (e.g. silicon nitride) suspended above a substrate. A coating of a sorptive material (e.g. a microporous hydrophobic sol-gel coating or a polymer coating) is formed on the suspended membrane proximate to the heating element to selective sorb one or more chemical species of interest over a time period, thereby concentrating the chemical species in the sorptive material. Upon heating the sorptive material with the resistive heating element, the sorbed chemical species are released for detection and analysis in a relatively high concentration and over a relatively short time period. The sorptive material can be made to selectively sorb particular chemical species of interest while not substantially sorbing other chemical species not of interest. The present invention has applications for use in forming high-sensitivity, rapid-response miniaturized chemical analysis systems (e.g. a "chem lab on a chip").

  19. Method of chemical analysis for oil shale wastes

    SciTech Connect

    Wallace, J.R.; Alden, L.; Bonomo, F.S.; Nichols, J.; Sexton, E.

    1984-06-01

    Several methods of chemical analysis are described for oil shale wastewaters and retort gases. These methods are designed to support the field testing of various pollution control systems. As such, emphasis has been placed on methods which are rapid and sufficiently rugged to perform well under field conditions. Ion chromatograph has been developed as a technique for the minor non-carbonate inorganic anions in retort water, including SO4, NO3, S2O3, SCN(-1), and total S. The method recommended for sulfide is a potiometric titration with Pb(II). The freezing point depression was used to determine the total solute content in retort waters, a test which can be considered analogous to the standard residue test. Three methods are described for the determination of total ammoniacal nitrogen in retort wastewaters: (1) a modified ion selective electrode technique, (2) an optical absorption technique, and (3) an ion chromatographic technique. Total sulfur in retort gas is determined by combusting the gas in a continuously flowing system, whereupon the resulting sulfur dioxide is determined by SO2 monitor. Individual sulfur species in retort gas including H2S, COS, SO2, and CH3CH2SH are determined by gas chromatography with flame photometric detection. Quality control, pH, conductivity, total inorganic carbon, and total organic carbon measurements are discussed briefly.

  20. Transcriptome Analysis in Domesticated Species: Challenges and Strategies

    PubMed Central

    Hekman, Jessica P.; Johnson, Jennifer L.; Kukekova, Anna V.

    2015-01-01

    Domesticated species occupy a special place in the human world due to their economic and cultural value. In the era of genomic research, domesticated species provide unique advantages for investigation of diseases and complex phenotypes. RNA sequencing, or RNA-seq, has recently emerged as a new approach for studying transcriptional activity of the whole genome, changing the focus from individual genes to gene networks. RNA-seq analysis in domesticated species may complement genome-wide association studies of complex traits with economic importance or direct relevance to biomedical research. However, RNA-seq studies are more challenging in domesticated species than in model organisms. These challenges are at least in part associated with the lack of quality genome assemblies for some domesticated species and the absence of genome assemblies for others. In this review, we discuss strategies for analyzing RNA-seq data, focusing particularly on questions and examples relevant to domesticated species. PMID:26917953

  1. High resolution melting analysis for the differentiation of Mycobacterium species.

    PubMed

    Issa, Rahizan; Abdul, Hatijah; Hashim, Siti Hasmah; Seradja, Valentinus H; Shaili, Nurul 'Aishah; Hassan, Nurul Akma Mohd

    2014-10-01

    A quantitative real-time PCR (qPCR) followed by high resolution melting (HRM) analysis was developed for the differentiation of Mycobacterium species. Rapid differentiation of Mycobacterium species is necessary for the effective diagnosis and management of tuberculosis. In this study, the 16S rRNA gene was tested as the target since this has been identified as a suitable target for the identification of mycobacteria species. During the temperature gradient and primer optimization process, the melting peak (Tm) analysis was determined at a concentration of 50 ng DNA template and 0.3, 0.4 and 0.5 µM primer. The qPCR assay for the detection of other mycobacterial species was done at the Tm and primer concentration of 62 °C and 0.4 µM, respectively. The HRM analysis generated cluster patterns that were specific and sensitive to distinguished small sequence differences of the Mycobacterium species. This study suggests that the 16S rRNA-based real-time PCR followed by HRM analysis produced unique cluster patterns for species of Mycobacterium and could differentiate the closely related mycobacteria species. © 2014 The Authors.

  2. SYSTEMS CHEMICAL ANALYSIS OF PETROLEUM POLLUTANTS

    EPA Science Inventory

    The application of an established mathematical treatment useful for the characterization and identification of petroleum pollutants is described. Using discriminant analysis of relevant infrared spectrophotometric data, 99% of numerous known and unknown oil samples have been corr...

  3. Comparative Analysis of Amaryllidaceae Alkaloids from Three Lycoris Species.

    PubMed

    Tian, Yongqiang; Zhang, Chunyun; Guo, Mingquan

    2015-12-07

    The major active constituents from Amaryllidaceae family were reported to be Amaryllidaceae alkaloids (AAs), which exhibited a wide spectrum of biological activities, such as anti-tumor, anti-viral, and acetyl-cholinesterase-inhibitory activities. In order to better understand their potential as a source of bioactive AAs and the phytochemical variations among three different species of Lycoris herbs, the HPLC fingerprint profiles of Lycoris aurea (L. aurea), L. radiata, and L. guangxiensis were firstly determined and compared using LC-UV and LC-MS/MS. As a result, 39 peaks were resolved and identified as AAs, of which nine peaks were found in common for all these three species, while the other 30 peaks could be revealed as characteristic AAs for L. aurea, L. radiata and L. guangxiensis, respectively. Thus, these AAs can be used as chemical markers for the identification and quality control of these plant species. To further reveal correlations between chemical components and their pharmaceutical activities of these species at the molecular level, the bioactivities of the total AAs from the three plant species were also tested against HepG2 cells with the inhibitory rate at 78.02%, 84.91% and 66.81% for L. aurea, L. radiata and L. guangxiensis, respectively. This study firstly revealed that the three species under investigation were different not only in the types of AAs, but also in their contents, and both contributed to their pharmacological distinctions. To the best of our knowledge, the current research provides the most detailed phytochemical profiles of AAs in these species, and offers valuable information for future valuation and exploitation of these medicinal plants.

  4. Biological and chemical properties of alkanediazotates as active species of N-nitroso compounds.

    PubMed

    Ukawa, S; Mochizuki, M

    1991-01-01

    The mutagenicity and chemical reactivity of (E)- and (Z)-potassium alkanediazotates, as precursors of corresponding alkanediazohydroxides, were investigated. In three microbial strains, Salmonella typhimurium TA1535 and Escherichia coli WP2 and WP2hcr-, the effect of changing the alkyl group on mutagenic potency was similar for (E)- and (Z)-diazotates, N-alkyl-N-nitrosoureas and alpha-hydroxynitrosamines. The capacity to alkylate nicotinamide, measured in an aqueous phosphate buffer, decreased with increasing alkyl chain length. Specific mutagenicity in S. typhimurium TA1535 was linearly related to alkylating activity. These results confirm that alkanediazohydroxides are the active alkylating species of N-nitroso compounds, and that their mutagenicity is determined by their alkylating activity.

  5. Chemical composition and antigerminative activity of the essential oils from five Salvia species.

    PubMed

    De Martino, Laura; Roscigno, Graziana; Mancini, Emilia; De Falco, Enrica; De Feo, Vincenzo

    2010-02-01

    The chemical composition of the essential oils of Salvia africana L., Salvia elegans Vahl, Salvia greggii A. Gray, Salvia mellifera Green and Salvia munzii Epling, cultivated in Eboli (Salerno, Southern Italy), was studied by means of GC and GC-MS analyses. In all, 88 compounds were identified, 54 for S. africana, accounting for 95.4% of the total oil, 55 for S. elegans (92.9%), 50 for S. greggii (96.9%), 54 for S. mellifera (90.4%) and 47 for S. munzii (97.5%), respectively. In S. africana,the amount of monoterpenoids and sesquiterpenoids is very similar. For other species, the monoterpenoid percentage is greater than the amount of sesquiterpenoids. The oils of S. elegans, S. greggii and S. munzii were active inhibitors of germination and radical elongation of Raphanus sativus L. and Lepidium sativum L.

  6. Bacterial colonization of the phyllosphere of mediterranean perennial species as influenced by leaf structural and chemical features.

    PubMed

    Yadav, R K P; Karamanoli, K; Vokou, D

    2005-08-01

    In this study, we assessed various leaf structural and chemical features as possible predictors of the size of the phyllosphere bacterial population in the Mediterranean environment. We examined eight perennial species, naturally occurring and coexisting in the same area, in Halkidiki (northern Greece). They are Arbutus unedo, Quercus coccifera, Pistacia lentiscus, and Myrtus communis (evergreen sclerophyllous species), Lavandula stoechas and Cistus incanus (drought semi-deciduous species), and Calamintha nepeta and Melissa officinalis (non-woody perennial species). M. communis, L. stoechas, C. nepeta, and M. officinalis produce essential oil in substantial quantities. We sampled summer leaves from these species and (1) estimated the size of the bacterial population of their phyllosphere, (2) estimated the concentration of different leaf constituents, and (3) studied leaf morphological and anatomical features and expressed them in a quantitative way. The aromatic plants are on average more highly colonized than the other species, whereas the non-woody perennials are more highly colonized than the woody species. The population size of epiphytic bacteria is positively correlated with glandular and non-glandular trichome densities, and with water and phosphorus contents; it is negatively correlated with total phenolics content and the thickness of the leaf, of the mesophyll, and of the abaxial epidermis. No correlation was found with the density of stomata, the nitrogen, and the soluble sugar contents. By regression tree analysis, we found that the leaf-microbe system can be effectively described by three leaf attributes with leaf water content being the primary explanatory attribute. Leaves with water content >73% are the most highly colonized. For leaves with water content <73%, the phosphorus content, with a critical value of 1.34 mg g(-1) d.w., is the next explanatory leaf attribute, followed by the thickness of the adaxial epidermis. Leaves higher in phosphorus

  7. Assessment of local wood species used for the manufacture of cookware and the perception of chemical benefits and chemical hazards associated with their use in Kumasi, Ghana.

    PubMed

    Mensah, John Kenneth; Adei, Evans; Adei, Dina; Owusu Ansah, Gwendolyn

    2012-12-18

    Historical proven wood species have no reported adverse health effect associated with its past use. Different historical proven species have traditionally been used to manufacture different wooden food contact items. This study uses survey questionnaires to assess suppliers', manufacturers', retailers' and consumers' (end-users') preferences for specific wood species, to examine the considerations that inform these preferences and to investigate the extent of awareness of the chemical benefits and chemical hazards associated with wooden food contact material use. Through the combined use of a cross sectional approach and a case study design, 25 suppliers, 25 manufacturers, 25 retailers and 125 consumers (end-users) of wooden food contact materials in four suburbs in Kumasi Metropolitan Area (Anloga junction, Ahinsan Bus Stop, Ahwia-Pankrono and Race Course) and Ashanti Akyim Agogo in the Ashanti Akyim North District of the Ashanti Region were administered with closed ended questionnaires. The questionnaires were prepared in English, but local language, Twi, was used to translate and communicate the content of the questionnaire where necessary. Suppliers', manufacturers' and retailers' preferences for specific wood species for most wooden cookware differed from that of consumers (end-users). But all respondent groups failed to indicate any awareness of chemical benefits or chemical hazards associated with either the choice of specific wood species for specific wooden cookware or with the general use of wooden food contact materials. The lack of appreciation of chemical benefits or hazards associated with active principles of wooden cookware led to heavy reliance of consumers (end-users) on the wood density, price, attractive grain pattern and colour or on the judgement of retailers in their choice of specific species for a wooden cookware. This study contributes some practical suggestions to guide national policy development on improvement in quality of available

  8. Assessment of local wood species used for the manufacture of cookware and the perception of chemical benefits and chemical hazards associated with their use in Kumasi, Ghana

    PubMed Central

    2012-01-01

    Background Historical proven wood species have no reported adverse health effect associated with its past use. Different historical proven species have traditionally been used to manufacture different wooden food contact items. This study uses survey questionnaires to assess suppliers’, manufacturers’, retailers’ and consumers’ (end-users’) preferences for specific wood species, to examine the considerations that inform these preferences and to investigate the extent of awareness of the chemical benefits and chemical hazards associated with wooden food contact material use. Methods Through the combined use of a cross sectional approach and a case study design, 25 suppliers, 25 manufacturers, 25 retailers and 125 consumers (end-users) of wooden food contact materials in four suburbs in Kumasi Metropolitan Area (Anloga junction, Ahinsan Bus Stop, Ahwia-Pankrono and Race Course) and Ashanti Akyim Agogo in the Ashanti Akyim North District of the Ashanti Region were administered with closed ended questionnaires. The questionnaires were prepared in English, but local language, Twi, was used to translate and communicate the content of the questionnaire where necessary. Results Suppliers’, manufacturers’ and retailers’ preferences for specific wood species for most wooden cookware differed from that of consumers (end-users). But all respondent groups failed to indicate any awareness of chemical benefits or chemical hazards associated with either the choice of specific wood species for specific wooden cookware or with the general use of wooden food contact materials. The lack of appreciation of chemical benefits or hazards associated with active principles of wooden cookware led to heavy reliance of consumers (end-users) on the wood density, price, attractive grain pattern and colour or on the judgement of retailers in their choice of specific species for a wooden cookware. Conclusion This study contributes some practical suggestions to guide national policy

  9. Chemical-specific adjustment factors (inter-species toxicokinetics) to establish the ADI for steviol glycosides.

    PubMed

    Roberts, Ashley; Lynch, Barry; Rogerson, Rebecca; Renwick, Andrew; Kern, Hua; Coffee, Matthew; Cuellar-Kingston, Nicole; Eapen, Alex; Crincoli, Christine; Pugh, George; Bhusari, Sachin; Purkayastha, Sidd; Carakostas, Michael

    2016-08-01

    The acceptable daily intake (ADI) of commercially available steviol glycosides is currently 0-4 mg/kg body weight (bw)/day, based on application of a 100-fold uncertainty factor to a no-observed-adverse-effect-level value from a chronic rat study. Within the 100-fold uncertainty factor is a 10-fold uncertainty factor to account for inter-species differences in toxicokinetics (4-fold) and toxicodynamics (2.5-fold). Single dose pharmacokinetics of stevioside were studied in rats (40 and 1000 mg/kg bw) and in male human subjects (40 mg/kg bw) to generate a chemical-specific, inter-species toxicokinetic adjustment factor. Tmax values for steviol were at ∼8 and ∼20 h after administration in rats and humans, respectively. Peak concentrations of steviol were similar in rats and humans, while steviol glucuronide concentrations were significantly higher in humans. Glucuronidation in rats was not saturated over the dose range 40-1000 mg/kg bw. The AUC0-last for steviol was approximately 2.8-fold greater in humans compared to rats. Chemical-specific adjustment factors for extrapolating toxicokinetics from rat to human of 1 and 2.8 were established based on Cmax and AUC0-last data respectively. Because these factors are lower than the default value of 4.0, a higher ADI for steviol glycosides of between 6 and 16 mg/kg bw/d is justified. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Chemical reactivation and aging kinetics of organophosphorus-inhibited cholinesterases from two earthworm species.

    PubMed

    Rodríguez-Castellanos, Laura; Sanchez-Hernandez, Juan C

    2007-09-01

    An in vitro study was conducted to evaluate the ability of pyridine-2-aldoxime methochloride (2-PAM) to recover organophosphorus (OP)-inhibited cholinesterase (ChE) activity of two earthworm species (Eisenia fetida and Lumbricus terrestris). After inhibition of ChE activity by OP pesticides, an alkyl group may be released from the OP-ChE complex. This reaction is termed aging, and the esterase cannot be reactivated either spontaneously or by the action of reactivating agents, such as 2-PAM. We also examined the aging kinetics of OP-inhibited ChE activity to evaluate the suitability of 2-PAM reactivation methodology for field monitoring. A 2-PAM concentration of 5 x 10(-4) M was enough to reactivate the OP-inhibited ChE activity after 60 min of incubation at 25 degrees C. Chemical reactivation kinetics followed an exponential rise to a maximum of 70 to 80% of normal enzyme activity when ChEs were inhibited with methyl paraoxon or dichlorvos and up to 60% for the chlorpyrifos-inhibited ChE of E. fetida. The aging rates (ka) of the inhibited ChEs were strongly affected by the OP type, and these rates decreased for both earthworm species in the following order: Methyl paraoxon (ka = 0.023-0.033/h) > dichlorvos (ka = 0.008-0.009/h) > chlorpyrifos oxon (ka = 0.003-0.006/h). In particular, chlorpyrifos-inhibited ChE activity of L. terrestris aged slowly (median aging time, 190 h), which means that chemical reactivation of esterase activity with 2-PAM seems feasible one week after exposure to OP pesticides. We conclude that reactivation of earthworm ChE activity by treatment with 2-PAM is a complementary and specific methodology for assessing exposure to OP pesticides.

  11. Alternative splicing in teleost fish genomes: same-species and cross-species analysis and comparisons.

    PubMed

    Lu, Jianguo; Peatman, Eric; Wang, Wenqi; Yang, Qing; Abernathy, Jason; Wang, Shaolin; Kucuktas, Huseyin; Liu, Zhanjiang

    2010-06-01

    Alternative splicing (AS) is a mechanism by which the coding diversity of the genome can be greatly increased. Rates of AS are known to vary according to the complexity of eukaryotic species potentially explaining the tremendous phenotypic diversity among species with similar numbers of coding genes. Little is known, however, about the nature or rate of AS in teleost fish. Here, we report the characteristics of AS in teleost fish and classification and frequency of five canonical AS types. We conducted both same-species and cross-species analysis utilizing the Genome Mapping and Alignment Program (GMAP) and an AS pipeline (ASpipe) to study AS in four genome-enabled species (Danio rerio, Oryzias latipes, Gasterosteus aculeatus, and Takifugu rubripes) and one species lacking a complete genome sequence, Ictalurus punctatus. AS frequency was lowest in the highly duplicated genome of zebrafish (17% of mapped genes). The compact genome of the pufferfish showed the highest occurrence of AS (approximately 43% of mapped genes). An inverse correlation between AS frequency and genome size was consistent across all analyzed species. Cross-species comparisons utilizing zebrafish as the reference genome allowed the identification of additional putative AS genes not revealed by zebrafish transcripts. Approximately, 50% of AS genes identified by same-species comparisons were shared among two or more species. A searchable website, the Teleost Alternative Splicing Database, was created to allow easy identification and visualization of AS transcripts in the studied teleost genomes. Our results and associated database should further our understanding of alternative splicing as an important functional and evolutionary mechanism in the genomes of teleost fish.

  12. A detailed pathway analysis of the chemical reaction system generating the Martian vertical ozone profile

    NASA Astrophysics Data System (ADS)

    Stock, Joachim W.; Blaszczak-Boxe, Christopher S.; Lehmann, Ralph; Grenfell, J. Lee; Patzer, A. Beate C.; Rauer, Heike; Yung, Yuk L.

    2017-07-01

    Atmospheric chemical composition is crucial in determining a planet's atmospheric structure, stability, and evolution. Attaining a quantitative understanding of the essential chemical mechanisms governing atmospheric composition is nontrivial due to complex interactions between chemical species. Trace species, for example, can participate in catalytic cycles - affecting the abundance of major and other trace gas species. Specifically, for Mars, such cycles dictate the abundance of its primary atmospheric constituent, carbon dioxide (CO2), but also for one of its trace gases, ozone (O3). The identification of chemical pathways/cycles by hand is extremely demanding; hence, the application of numerical methods, such as the Pathway Analysis Program (PAP), is crucial to analyze and quantitatively exemplify chemical reaction networks. Here, we carry out the first automated quantitative chemical pathway analysis of Mars' atmosphere with respect to O3. PAP was applied to JPL/Caltech's 1-D updated photochemical Mars model's output data. We determine all significant chemical pathways and their contribution to O3 production and consumption (up to 80 km) in order to investigate the mechanisms causing the characteristic shape of the O3 volume mixing ratio profile, i.e. a ground layer maximum and an ozone layer at ∼50 km. These pathways explain why an O3 layer is present, why it is located at that particular altitude and what the different processes forming the near-surface and middle atmosphere O3 maxima are. Furthermore, we show that the Martian atmosphere can be divided into two chemically distinct regions according to the O(3P):O3 ratio. In the lower region (below approximately 24 km altitude) O3 is the most abundant Ox (= O3 + O(3P)) species. In the upper region (above approximately 24 km altitude), where the O3 layer is located, O(3P) is the most abundant Ox species. Earlier results concerning the formation of O3 on Mars can now be explained with the help of chemical

  13. Source analysis of underground chemical explosions

    NASA Astrophysics Data System (ADS)

    Chiang, A.; Ford, S. R.; Pitarka, A.

    2016-12-01

    Several physical mechanisms have been proposed to explain the generation of S-waves from underground explosions, such as asymmetries in the source, release of tectonic pre-stress, interactions with the free-surface, and heterogeneities in the Earth. An accurate description of the explosion source processes is an important step towards understanding which of these plausible mechanisms are actively contributing to the generation of S-waves and under what conditions. In this study we investigate the sensitivity of far-field waveforms to seismic source mechanisms by comparing simulated and recorded data from underground chemical explosions performed during the Source Physics Experiment. We use both forward and inverse waveform modeling approaches to estimate the source properties of the explosions, and compare solutions using different velocity models and at different frequency bands and distances. 1D and 3D velocity models are used to characterize wave propagation between the source and receiver. The 3D velocity models are constructed using available geological and geophysical data, and ambient noise seismic tomography. The 3D Green's functions are computed using a numerical finite-difference approach. We will investigate the sensitivity of far-field ground motion to different levels of source complexities, such as a single isotropic source or complex sources with non-isotropic radiation in the frequency range of 0.5 to 6 Hz.

  14. Chemical composition of essential oils from four Vietnamese species of piper (piperaceae).

    PubMed

    Hieu, Le D; Thang, Tran D; Hoi, Tran M; Ogunwande, Isiaka A

    2014-01-01

    The chemical composition of essential oils from four Piper species, Piper retrofractum Vahl., P. boehmeriaefolium (Miq.) C. DC., P. sarmentosum Roxb., and P. maclurei Merr., were analysed by gas chromatography-flame ionization detector (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Nineteen to sixty-four compounds representing 92.0%-98.4% of the total contents were identified in the oil samples. The major constituents identified in P. retrofractum leaf oil were benzyl benzoate (14.4%), myrcene (14.4%), bicycloelemene (9.9%), bicyclogermacrene (7.0%) and β-caryophyllene (5.3%). On the other hand, the main constituents of P. boehmeriaefolium were α-copaene (28.3%), α-pinene (7.4%) and 1, 8-cineole (5.7%). P. sarmentosum showed a very different chemical profile characterized mainly by aromatic compounds and devoid of monoterpene hydrocarbons. The major constituents were benzyl benzoate (49.1%), benzyl alcohol (17.9%), 2-hydroxy-benzoic acid phenylmethyl ester (10.0%) and 2-butenyl-benzene (7.9%). The leaf of P. maclurei was characterized by higher amount of (E)-cinnamic acid (37.4%) and (E)-nerolidol (19.4%). Moreover, (Z)-9-octadecanoic acid methyl ester (28.0%), (E)-cinnamyl acetate (17.2%), phytol (12.2%) and (E)-cinnamaldehyde (8.8%) were the major compounds identified in the stem oil.

  15. Chemical fate and biological effects of several endocrine disrupters compounds in two echinoderm species.

    PubMed

    Sugni, Michela; Tremolada, Paolo; Porte, Cinta; Barbaglio, Alice; Bonasoro, Francesco; Carnevali, M Daniela Candia

    2010-03-01

    Two echinoderm species, the sea urchin Paracentrotus lividus and the feather star Antedon mediterranea, were exposed for 28 days to several EDCs: three putative androgenic compounds, triphenyltin (TPT), fenarimol (FEN), methyltestosterone (MET), and two putative antiandrogenic compounds, p,p'-DDE (DDE) and cyproterone acetate (CPA). The exposure nominal concentrations were from 10 to 3000 ng L(-1), depending on the compound. This paper is an attempt to join three different aspects coming from our ecotoxicological tests: (1) the chemical behaviour inside the experimental system; (2) the measured toxicological endpoints; (3) the biochemical responses, to which the measured endpoints may depend. The chemical fate of the different compounds was enquired by a modelling approach throughout the application of the 'Aquarium model'. An estimation of the day-to-day concentration levels in water and biota were obtained together with the amount assumed each day by each animal (uptake in microg animal(-1) d(-1) or ng g-wet weight(-1) d(-1)). The toxicological endpoints investigated deal with the reproductive potential (gonad maturation stage, gonad index and oocyte diameter) and with the regenerative potential (growth and histology). Almost all the compounds exerted some kind of effect at the tested concentrations, however TPT was the most effective in altering both reproductive and regenerative parameters (also at the concentration of few ng L(-1)). The biochemical analyses of testosterone (T) and 17beta-estradiol (E(2)) also showed the ability of the selected compounds to significantly alter endogenous steroid concentrations.

  16. Methods for Chemical Analysis of Fresh Waters.

    ERIC Educational Resources Information Center

    Golterman, H. L.

    This manual, one of a series prepared for the guidance of research workers conducting studies as part of the International Biological Programme, contains recommended methods for the analysis of fresh water. The techniques are grouped in the following major sections: Sample Taking and Storage; Conductivity, pH, Oxidation-Reduction Potential,…

  17. Methods for Chemical Analysis of Fresh Waters.

    ERIC Educational Resources Information Center

    Golterman, H. L.

    This manual, one of a series prepared for the guidance of research workers conducting studies as part of the International Biological Programme, contains recommended methods for the analysis of fresh water. The techniques are grouped in the following major sections: Sample Taking and Storage; Conductivity, pH, Oxidation-Reduction Potential,…

  18. Electron Spectroscopy: Applications for Chemical Analysis

    ERIC Educational Resources Information Center

    Heercules, David M.

    2004-01-01

    The development of XPS as an effective method for surface analysis during the period 1964-1977 is presented. The study shows that unlike other surface methods, XPS data can be obtained for both conductors and insulators and a variety of samples can be handled effectively, which is one of the major reasons for the popularity of the technique.

  19. Chemical map of Schizosaccharomyces pombe reveals species-specific features in nucleosome positioning

    PubMed Central

    Moyle-Heyrman, Georgette; Zaichuk, Tetiana; Xi, Liqun; Zhang, Quanwei; Uhlenbeck, Olke C.; Holmgren, Robert; Widom, Jonathan; Wang, Ji-Ping

    2013-01-01

    Using a recently developed chemical approach, we have generated a genome-wide map of nucleosomes in vivo in Schizosaccharomyces pombe (S. pombe) at base pair resolution. The shorter linker length previously identified in S. pombe is due to a preponderance of nucleosomes separated by ∼4/5 bp, placing nucleosomes on opposite faces of the DNA. The periodic dinucleotide feature thought to position nucleosomes is equally strong in exons as in introns, demonstrating that nucleosome positioning information can be superimposed on coding information. Unlike the case in Saccharomyces cerevisiae, A/T-rich sequences are enriched in S. pombe nucleosomes, particularly at ±20 bp around the dyad. This difference in nucleosome binding preference gives rise to a major distinction downstream of the transcription start site, where nucleosome phasing is highly predictable by A/T frequency in S. pombe but not in S. cerevisiae, suggesting that the genomes and DNA binding preferences of nucleosomes have coevolved in different species. The poly (dA-dT) tracts affect but do not deplete nucleosomes in S. pombe, and they prefer special rotational positions within the nucleosome, with longer tracts enriched in the 10- to 30-bp region from the dyad. S. pombe does not have a well-defined nucleosome-depleted region immediately upstream of most transcription start sites; instead, the −1 nucleosome is positioned with the expected spacing relative to the +1 nucleosome, and its occupancy is negatively correlated with gene expression. Although there is generally very good agreement between nucleosome maps generated by chemical cleavage and micrococcal nuclease digestion, the chemical map shows consistently higher nucleosome occupancy on DNA with high A/T content. PMID:24277842

  20. Impact of environmentally based chemical hardness on uranium speciation and toxicity in six aquatic species.

    PubMed

    Goulet, Richard R; Thompson, Patsy A; Serben, Kerrie C; Eickhoff, Curtis V

    2015-03-01

    Treated effluent discharge from uranium (U) mines and mills elevates the concentrations of U, calcium (Ca), magnesium (Mg), and sulfate (SO4 (2-) ) above natural levels in receiving waters. Many investigations on the effect of hardness on U toxicity have been experiments on the combined effects of changes in hardness, pH, and alkalinity, which do not represent water chemistry downstream of U mines and mills. Therefore, more toxicity studies with water chemistry encountered downstream of U mines and mills are necessary to support predictive assessments of impacts of U discharge to the environment. Acute and chronic U toxicity laboratory bioassays were realized with 6 freshwater species in waters of low alkalinity, circumneutral pH, and a range of chemical hardness as found in field samples collected downstream of U mines and mills. In laboratory-tested waters, speciation calculations suggested that free uranyl ion concentrations remained constant despite increasing chemical hardness. When hardness increased while pH remained circumneutral and alkalinity low, U toxicity decreased only to Hyalella azteca and Pseudokirchneriella subcapitata. Also, Ca and Mg did not compete with U for the same uptake sites. The present study confirms that the majority of studies concluding that hardness affected U toxicity were in fact studies in which alkalinity and pH were the stronger influence. The results thus confirm that studies predicting impacts of U downstream of mines and mills should not consider chemical hardness. Environ Toxicol Chem 2015;34:562-574. © 2014 The Authors. Published by Wiley Periodicals, Inc. on behalf of SETAC. © 2014 The Authors. Published by Wiley Periodicals, Inc. on behalf of SETAC.

  1. Chemical map of Schizosaccharomyces pombe reveals species-specific features in nucleosome positioning.

    PubMed

    Moyle-Heyrman, Georgette; Zaichuk, Tetiana; Xi, Liqun; Zhang, Quanwei; Uhlenbeck, Olke C; Holmgren, Robert; Widom, Jonathan; Wang, Ji-Ping

    2013-12-10

    Using a recently developed chemical approach, we have generated a genome-wide map of nucleosomes in vivo in Schizosaccharomyces pombe (S. pombe) at base pair resolution. The shorter linker length previously identified in S. pombe is due to a preponderance of nucleosomes separated by ∼4/5 bp, placing nucleosomes on opposite faces of the DNA. The periodic dinucleotide feature thought to position nucleosomes is equally strong in exons as in introns, demonstrating that nucleosome positioning information can be superimposed on coding information. Unlike the case in Saccharomyces cerevisiae, A/T-rich sequences are enriched in S. pombe nucleosomes, particularly at ±20 bp around the dyad. This difference in nucleosome binding preference gives rise to a major distinction downstream of the transcription start site, where nucleosome phasing is highly predictable by A/T frequency in S. pombe but not in S. cerevisiae, suggesting that the genomes and DNA binding preferences of nucleosomes have coevolved in different species. The poly (dA-dT) tracts affect but do not deplete nucleosomes in S. pombe, and they prefer special rotational positions within the nucleosome, with longer tracts enriched in the 10- to 30-bp region from the dyad. S. pombe does not have a well-defined nucleosome-depleted region immediately upstream of most transcription start sites; instead, the -1 nucleosome is positioned with the expected spacing relative to the +1 nucleosome, and its occupancy is negatively correlated with gene expression. Although there is generally very good agreement between nucleosome maps generated by chemical cleavage and micrococcal nuclease digestion, the chemical map shows consistently higher nucleosome occupancy on DNA with high A/T content.

  2. Comparison of tropical and temperate freshwater animal species' acute sensitivities to chemicals: implications for deriving safe extrapolation factors.

    PubMed

    Kwok, Kevin W H; Leung, Kenneth M Y; Lui, Gilbert S G; Chu, S Vincent K H; Lam, Paul K S; Morritt, David; Maltby, Lorraine; Brock, Theo C M; Van den Brink, Paul J; Warne, Michael St J; Crane, Mark

    2007-01-01

    Toxicity data for tropical species are often lacking for ecological risk assessment. Consequently, tropical and subtropical countries use water quality criteria (WQC) derived from temperate species (e.g., United States, Canada, or Europe) to assess ecological risks in their aquatic systems, leaving an unknown margin of uncertainty. To address this issue, we use species sensitivity distributions of freshwater animal species to determine whether temperate datasets are adequately protective of tropical species assemblages for 18 chemical substances. The results indicate that the relative sensitivities of tropical and temperate species are noticeably different for some of these chemicals. For most metals, temperate species tend to be more sensitive than their tropical counterparts. However, for un-ionized ammonia, phenol, and some pesticides (e.g., chlorpyrifos), tropical species are probably more sensitive. On the basis of the results from objective comparisons of the ratio between temperate and tropical hazardous concentration values for 10% of species, or the 90% protection level, we recommend that an extrapolation factor of 10 should be applied when such surrogate temperate WQCs are used for tropical or subtropical regions and a priori knowledge on the sensitivity of tropical species is very limited or not available.

  3. Predicting the hazardous dose of industrial chemicals in warm-blooded species using machine learning-based modelling approaches.

    PubMed

    Gupta, S; Basant, N; Singh, K P

    2015-06-01

    The hazardous dose of a chemical (HD50) is an emerging and acceptable test statistic for the safety/risk assessment of chemicals. Since it is derived using the experimental toxicity values of the chemical in several test species, it is highly cumbersome, time and resource intensive. In this study, three machine learning-based QSARs were established for predicting the HD50 of chemicals in warm-blooded species following the OECD guidelines. A data set comprising HD50 values of 957 chemicals was used to develop SDT, DTF and DTB QSAR models. The diversity in chemical structures and nonlinearity in the data were verified. Several validation coefficients were derived to test the predictive and generalization abilities of the constructed QSARs. The chi-path descriptors were identified as the most influential in three QSARs. The DTF and DTB performed relatively better than SDT model and yielded r(2) values of 0.928 and 0.959 between the measured and predicted HD50 values in the complete data set. Substructure alerts responsible for the toxicity of the chemicals were identified. The results suggest the appropriateness of the developed QSARs for reliably predicting the HD50 values of chemicals, and they can be used for screening of new chemicals for their safety/risk assessment for regulatory purposes.

  4. Anti-Inflammatory Properties and Chemical Characterization of the Essential Oils of Four Citrus Species

    PubMed Central

    Amorim, Jorge Luis; Simas, Daniel Luiz Reis; Pinheiro, Mariana Martins Gomes; Moreno, Daniela Sales Alviano; Alviano, Celuta Sales; da Silva, Antonio Jorge Ribeiro

    2016-01-01

    Citrus fruits have potential health-promoting properties and their essential oils have long been used in several applications. Due to biological effects described to some citrus species in this study our objectives were to analyze and compare the phytochemical composition and evaluate the anti-inflammatory effect of essential oils (EO) obtained from four different Citrus species. Mice were treated with EO obtained from C. limon, C. latifolia, C. aurantifolia or C. limonia (10 to 100 mg/kg, p.o.) and their anti-inflammatory effects were evaluated in chemical induced inflammation (formalin-induced licking response) and carrageenan-induced inflammation in the subcutaneous air pouch model. A possible antinociceptive effect was evaluated in the hot plate model. Phytochemical analyses indicated the presence of geranial, limonene, γ-terpinene and others. EOs from C. limon, C. aurantifolia and C. limonia exhibited anti-inflammatory effects by reducing cell migration, cytokine production and protein extravasation induced by carrageenan. These effects were also obtained with similar amounts of pure limonene. It was also observed that C. aurantifolia induced myelotoxicity in mice. Anti-inflammatory effect of C. limon and C. limonia is probably due to their large quantities of limonene, while the myelotoxicity observed with C. aurantifolia is most likely due to the high concentration of citral. Our results indicate that these EOs from C. limon, C. aurantifolia and C. limonia have a significant anti-inflammatory effect; however, care should be taken with C. aurantifolia. PMID:27088973

  5. Anti-Inflammatory Properties and Chemical Characterization of the Essential Oils of Four Citrus Species.

    PubMed

    Amorim, Jorge Luis; Simas, Daniel Luiz Reis; Pinheiro, Mariana Martins Gomes; Moreno, Daniela Sales Alviano; Alviano, Celuta Sales; da Silva, Antonio Jorge Ribeiro; Fernandes, Patricia Dias

    2016-01-01

    Citrus fruits have potential health-promoting properties and their essential oils have long been used in several applications. Due to biological effects described to some citrus species in this study our objectives were to analyze and compare the phytochemical composition and evaluate the anti-inflammatory effect of essential oils (EO) obtained from four different Citrus species. Mice were treated with EO obtained from C. limon, C. latifolia, C. aurantifolia or C. limonia (10 to 100 mg/kg, p.o.) and their anti-inflammatory effects were evaluated in chemical induced inflammation (formalin-induced licking response) and carrageenan-induced inflammation in the subcutaneous air pouch model. A possible antinociceptive effect was evaluated in the hot plate model. Phytochemical analyses indicated the presence of geranial, limonene, γ-terpinene and others. EOs from C. limon, C. aurantifolia and C. limonia exhibited anti-inflammatory effects by reducing cell migration, cytokine production and protein extravasation induced by carrageenan. These effects were also obtained with similar amounts of pure limonene. It was also observed that C. aurantifolia induced myelotoxicity in mice. Anti-inflammatory effect of C. limon and C. limonia is probably due to their large quantities of limonene, while the myelotoxicity observed with C. aurantifolia is most likely due to the high concentration of citral. Our results indicate that these EOs from C. limon, C. aurantifolia and C. limonia have a significant anti-inflammatory effect; however, care should be taken with C. aurantifolia.

  6. Polymers as directing agents for motions of chemical and biological species

    NASA Astrophysics Data System (ADS)

    Tanyeri, Nihan Yonet

    This thesis involves descriptions of solid surface modifications with various polymeric materials which were used as a guiding agent for motion of chemical and biological species. Quasi-two dimensional poly(oligoethylene glycol) acrylate polymer brush based molecular conduits have been designed with the goal of regulating and controlling the diffusive transport of molecular, e.g. organic dyes, and ionic species, e.g. AuCl4-, and Cu2+ ions, along predefined 2-D pathways. The transport of these chemical species has been examined by both fluorescence and dark field microscopy. The polymer brushes were formed through microcontact printing of an initiator, followed by surface-initiated Atom Transfer Radical Polymerization (SI-ATRP). SI-ATRP enables both 2-D patterning with a resolution of about 1 micrometer, and control over the resultant polymer brush thickness (which was varied from 10-100 nm). A hydrophilic poly(oligoethylene glycol) acrylate brushe was selected because of its potential to dissolve a wide range of hydrophilic species. The transport of fluorescent species can be directly followed. A non-lithographic fabrication method was developed for mufluidic devices used in the diffusion studies. Singular channel mufluidic device was utilized to study the directed organic dye diffusion. The AuCl4-, and Cu 2+ ion transport was studied by designing molecular devices with two mufluidic channels. We have demonstrated that the various species of interest diffuse much more rapidly along the predefined pathway than along the bare (polymer brush free) regions of the substrate, demonstrating that diffusive conduits for molecular transport can indeed be formed. The protein resistance of poly(N-isopropylacrylamide) (PNIPAM) brushes grafted from silicon wafers was investigated as a function of the chain molecular weight, grafting density, and temperature. Above the lower critical solution temperature (LCST) of 32°C, the collapse of the water swollen chains, determined by

  7. Natural background concentrations and threshold values of chemical species for groundwater in Korea

    NASA Astrophysics Data System (ADS)

    Hyun, Y.; Lee, S.; Lee, H.

    2014-12-01

    We analyze natural background concentrations and determine threshold values of chemical species (NO3-N, Cl, As, Pb, Cr) for groundwater using Groundwater Quality Monitoring Network (GQMN) data operated by Korea Ministry of Environment (ME). GQMN data are divided into two groups, A and B. Group A consists of samples collected in aquifers where anthropogenic inputs are forced to be excluded by aquifer typology. Group B consists of samples in aquifers where purely anthropogenic chemicals (e.g., pesticide, PAC) are introduced at the downgradient. Group A is used to derive nationwide natural background concentrations for groundwater in specific aquifer geology under concern, which represents a reference system. Group B is used for deriving site-specific background concentrations for groundwater. For both groups of data, the samples with anthropogenic inputs are forced to be excluded, thus background concentrations are derived based on a pre-selection method accordingly. We determine threshold values according to EU GroundWater Daughter Directive(GWDD 2006/11/EC). For As, Pb, and Cr and some other trace elements, survival analyses are used for estimating background concentrations due to non-detect data. The results show that high concentration values of NO3-N and Cr are related to high natural background concentrations due to rock-water interactions for Group A. In particular, NO3-N concentrations vary with depth, which are consistent with natural attenuation processes. For Group B, some anthropogenic chemical species such as BTEX are observed and site-specific background concentrations of those elements are non-zero, which is apparently not naturally occurred at all. Natural background concentrations and threshold values derived from Group A can be used for setting up reference values for managing groundwater quality on a level of either domestic or drinking water stands. Meanwhile results from Group B provide a useful guidance for managing groundwater quality in

  8. Species Discrimination of Mangroves using Derivative Spectral Analysis

    NASA Astrophysics Data System (ADS)

    Prasad, K. Arun; Gnanappazham, L.

    2014-11-01

    Mangroves are salt tolerant trees or shrubs commonly seen in mudflats of intertidal regions of tropical and subtropical coastlines. Recent advances in field spectroscopic techniques enabled the species level discrimination among closely related vegetation types. In this study we have analysed the laboratory spectroscopy data collected from eight species of Rhizophoraceaea family of mangroves. The spectral data ranges between the wavelength of 350 nm and 2500 nm at a very narrow bandwidth of 1 nm. Preprocessing techniques including smoothing were done on the spectra to remove the noise before compiling it to a spectral library. Derivative analysis of the spectra was done and its corresponding first and second derivatives were obtained. Statistical analysis such as parametric and non-parametric tests were implemented on the original processed spectra as well as their respective first and second order derivatives for the identification of significant bands for species discrimination. Results have shown that red edge region (680 nm - 720 nm) and water vapour absorption region around 1150 nm and 1400 nm are optimal as they were consistent in discriminating species in reflectance spectra as well as in its first and second derivative spectra. C. decandra species is found to be discriminable from other species while reflectance and its derivative spectra were used. Non-parametric statistical analysis gave better results than that of parametric statistical analysis especially in SWIR 2 spectral region (1831 nm - 2500 nm).

  9. In Situ Infrared Spectroscopy of the Gaseous Species Present in a Diamond Chemical Vapor Deposition System

    NASA Technical Reports Server (NTRS)

    Morell, G.; Weiner, B. R.

    1998-01-01

    We interfaced a Hot-Filament Chemical Vapor Deposition (HFCVD) system to the emission port of an FT-IR spectrometer, in order to study the gas phase species present during the deposition of diamond thin films. The implementation of the infrared (IR) emission technique in situ allowed the study of various carbon-containing species believed to be crucial in diamond film growth. The two IR-active vibrational fundamentals of methane, v(3)(f2) and v(4)(f2), were observed at three different filament temperatures: 1000, 1500 and 2000 C. However, the net signal of v(3) was emission, while that of v(4) was absorption. These results indicate that the v(4) fundamental is excited beyond equilibrium, while the v(3) fundamental remains mostly in the ground state. This is due to the small concentration of methane, the low energy of v(4) compared to v(3) or to the Hz vibrational mode, and symmetry considerations that forbid interaction among the four fundamentals of methane. Thus, the excitation of v(3) is more likely than its decay under HFCVD conditions, producing a non-equilibrium population. At a filament temperature of 2000 C, the v(3) (sigma(+)(3)) fundamental of acetylene and a band at 1328 cm-l also ascribed to acetylene (v5 (pi(U)) + v4) appear in net absorption. This correlates well with the onset of molecular hydrogen breaking by the filament, which occurs at temperatures around 2000 C and above. The hydrogen atoms produced in this heterogeneous reaction give rise to a chain of reactions that lead to acetylene, among other carbonaceous species.

  10. In Situ Infrared Spectroscopy of the Gaseous Species Present in a Diamond Chemical Vapor Deposition System

    NASA Technical Reports Server (NTRS)

    Morell, G.; Weiner, B. R.

    1998-01-01

    We interfaced a Hot-Filament Chemical Vapor Deposition (HFCVD) system to the emission port of an FT-IR spectrometer, in order to study the gas phase species present during the deposition of diamond thin films. The implementation of the infrared (IR) emission technique in situ allowed the study of various carbon-containing species believed to be crucial in diamond film growth. The two IR-active vibrational fundamentals of methane, v(3)(f2) and v(4)(f2), were observed at three different filament temperatures: 1000, 1500 and 2000 C. However, the net signal of v(3) was emission, while that of v(4) was absorption. These results indicate that the v(4) fundamental is excited beyond equilibrium, while the v(3) fundamental remains mostly in the ground state. This is due to the small concentration of methane, the low energy of v(4) compared to v(3) or to the Hz vibrational mode, and symmetry considerations that forbid interaction among the four fundamentals of methane. Thus, the excitation of v(3) is more likely than its decay under HFCVD conditions, producing a non-equilibrium population. At a filament temperature of 2000 C, the v(3) (sigma(+)(3)) fundamental of acetylene and a band at 1328 cm-l also ascribed to acetylene (v5 (pi(U)) + v4) appear in net absorption. This correlates well with the onset of molecular hydrogen breaking by the filament, which occurs at temperatures around 2000 C and above. The hydrogen atoms produced in this heterogeneous reaction give rise to a chain of reactions that lead to acetylene, among other carbonaceous species.

  11. Elucidation of the chemical environment for zinc species in an electron-rich zinc-incorporated zeolite

    SciTech Connect

    Wang, Jing-Feng; Wang, Kai-Xue; Wang, Jian-Qiang; Li, Lu; Jiang, Yan-Mei; Guo, Xing-Xing; Chen, Jie-Sheng

    2013-06-15

    An electron-rich zinc-modified zeolite has been prepared by the incorporation of zinc vapor into the channels of a dehydrated HY (protonated zeolite Y). The chemical environment of the zinc species in the electron-rich zeolite has been elucidated on the basis of X-ray absorption spectroscopy. The formation of univalent zinc (Zn{sup +}) within the electron-rich zeolite was observed upon the irradiation of X-ray from either a synchrotron radiation source or a conventional X-ray diffractometer. The X-ray irradiation initiated the electron transfer from the electron-rich framework of zeolite Y to the nearby Zn{sup 2+} cations, generating Zn{sup +} species. The variation of the coordination environment of the zinc species upon interaction with water molecules has also been investigated. - Graphical abstract: The chemical environment of the zinc species in an electorn-rich zeolite has been elucidated on the basis of X-ray absorption spectroscopy. - Highlights: • An electron-rich zinc-incorporated zeolite has been prepared by chemical vapor reaction. • Univalent zinc is detected after the electron-rich zeolite is irradiated with X-ray. • The chemical environment of the zinc species is elucidated by X-ray absorption spectroscopy. • The coordination environment of the zinc species changes upon interaction with water molecules.

  12. Pretest uncertainty analysis for chemical rocket engine tests

    NASA Technical Reports Server (NTRS)

    Davidian, Kenneth J.

    1987-01-01

    A parametric pretest uncertainty analysis has been performed for a chemical rocket engine test at a unique 1000:1 area ratio altitude test facility. Results from the parametric study provide the error limits required in order to maintain a maximum uncertainty of 1 percent on specific impulse. Equations used in the uncertainty analysis are presented.

  13. Sensory characterization, physico-chemical properties and somatic yields of five emerging fish species.

    PubMed

    Lazo, Oxana; Guerrero, Luis; Alexi, Niki; Grigorakis, Kriton; Claret, Anna; Pérez, José A; Bou, Ricard

    2017-10-01

    Aquaculture plays an important role in supplying the fresh fish. However its production is dominated by only few long-established species that in turn limit the variety of available products in the market. Therefore, new fish species need to be properly introduced to create a diversification in the current market. In order to achieve this goal, it is important to know, understand and characterize their quality features so they can be addressed to local and global markets. Sensory, compositional, instrumental texture parameters and somatic properties of five emerging fish species, namely wreckfish, greater amberjack, grey mullet, meagre, and pikeperch, were examined for characterization purposes. Sensory references were specifically developed for the training of the assessors, both from a qualitative and quantitative perspective. Twenty two sensory descriptors were used for describing the samples. Several differences were observed among the measured parameters. Somatic measures revealed the filleting yield to be the most important of them. Regarding the compositional parameters, fat content was among the most relevant discriminating aspect between species, while hardness was among the most differentiating ones when dealing with texture. Greater amberjack was described with sour flavor, pikeperch was associated to an earthy flavor and grey mullet was characterized by bitter flavor. Sensory firmness was clearly distinctive for wreckfish, while meagre related to juicy texture. The analysis of the relationship between all parameters provided important correlations, especially those related to texture parameters, fat content, laminar structure and teeth adherence. The species in this study exhibited a wide range of physicochemical and sensory characteristics that show their potential for being further exploited when designing new products. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Chemical taxonomy of red-flowered wild Camellia species based on floral anthocyanins.

    PubMed

    Li, Jian-Bin; Hashimoto, Fumio; Shimizu, Keiichi; Sakata, Yusuke

    2013-01-01

    This study uses anthocyanins in the red flowers of section Camellia as taxonomic markers to investigate the phenetic relationships among 33 wild species from China, Taiwan, and Japan. The 25 anthocyanins from section Camellia produced 38 pigment patterns that serve as phenetic markers. Principal Component Analysis (PCA) indicated that the attachment of one or two glucoses to the cyanidin-core structure at the 3- or the 3- and 5-positions, respectively, was the most influential pattern against the first factor, Z₁. In addition, two alternative pigment patterns, acylated or non-acylated, and the structural isomerism (cis- or trans-) of the p-coumaroyl group were relatively significant patterns. Ward's minimum-variance cluster analysis (WMVCA) produced a dendrogram that consisted of two sub-clusters. One sub-cluster (A) was constructed by species that have mainly two types of anthocyanins: 3,5-di-O-β-glucosides (Camellia saluenensis) and sambubioside of cyanidin (Camellia reticulata). The other sub-cluster (B) was made up of the 3-O-β-glucosides of cyanidin (Camellia japonica) and delphinidin (Camellia hongkongensis), with a higher proportion of the 3-O-β-galactosides (Camellia mairei and Camellia boreali-yunnanica). The former group showed a higher proportion of acylation, over 63%, but with the exception of Camellia azalea. The latter group showed less than 52% acylation, but with the exception of C. hongkongensis and C. boreali-yunnanica. PCA and WMVCA indicated that the greater the amount of di-O-glycosides and acylation, the more primitive anthocyanin traits the species possess. Based on these results, in conjunction with geographical and literary information, the data suggest that the Xinan district is the site/center of origin for the red-flowered Camellia species of which both C. saluenensis and C. reticulata have the most primitive anthocyanin traits.

  15. Distribution of persistent organochlorine chemical residues in blood plasma of three species of vultures from India.

    PubMed

    Dhananjayan, Venugopal; Muralidharan, Subramanian; Jayanthi, Palanisamy

    2011-02-01

    The presence of persistent organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were determined in blood plasma of white-backed vulture Gyps bengalensis, Egyptian vulture Neophron percnopterus, and griffon vulture Gyps fulvus collected from Ahmedabad, India. All the samples had varying levels of organochlorine pesticides and PCBs. Statistically significant (P<0.05) differences among species were detected for beta-hexachlorocyclohexane (β-HCH), ∑HCH, and dichloro-diphenyl-trichloroethane (DDT). The mean concentration of ∑HCH, ∑DDT, and ∑PCBs among plasma ranged from 43.7 to 136, 8.8 to 64.8, and 226 to 585 ng/ml, respectively. Among the various OCPs analyzed, 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p'-DDE) was detected most frequently. The concentrations of cyclodiene insecticides detected were lower than the other organochlorine residues. The levels of pesticides measured in plasma samples of three species of vulture were comparable to the results documented for a number of avian species and were lower than those reported to have deleterious effects on survival or reproduction of birds. Although no threat is posed by any of the organochlorine pesticides detected, continuous monitoring of breeding colonies is recommended. This study is also the first account of a comprehensive analysis of toxicants present in blood plasma of vulture species in India. The values reported in this study can serve as guidelines for future research in general as well as control values during the analysis of samples obtained from birds in the event of suspected organochlorine poisoning.

  16. Interactions among chemical components of Cocoa tea (Camellia ptilophylla Chang), a naturally low caffeine-containing tea species.

    PubMed

    Lin, Xiaorong; Chen, Zhongzheng; Zhang, Yuanyuan; Gao, Xiong; Luo, Wei; Li, Bin

    2014-06-01

    In the 1980s, a novel tea species, Cocoa tea (Camellia ptilophylla Chang), was discovered in Southern China with surprisingly low caffeine content (0.2% by dry weight). Although its health promoting characteristics have been known for a while, a very limited amount of scientific research has been focused on Cocoa tea. Herein, a systematic study on Cocoa tea and its chemical components, interactions and bioactivities was performed. YD tea (Yunnan Daye tea, Camellia sinensis), a tea species with a high caffeine content (5.8% by dry weight), was used as a control. By UV-Vis spectrometry, High Performance Liquid Chromatography (HPLC), and Flame Atomic Absorption Spectrometry (FAAS) for chemical composition analysis, C-2 epimeric isomers of tea catechins and theobromine were found to be the major catechins and methylxanthine in Cocoa tea, respectively. More gallated catechins, methylxanthines, and proteins were detected in Cocoa tea compared with YD tea. Moreover, the tendency of major components in Cocoa tea for precipitation was significantly higher than that in YD tea. Catechins, methylxanthines, proteins, iron, calcium, and copper were presumed to be the origins of molecular interactions in Cocoa tea and YD tea. The interactions between catechins and methylxanthines were highly related to the galloyl moiety in catechins and methyl groups in methylxanthines. In vitro anti-inflammatory activity assays revealed that Cocoa tea was a more potent inhibitor of nitric oxide (NO) in lipopolysaccharide (LPS)-stimulated macrophage cells (RAW 264.7) than YD tea. This study constructs a solid phytochemical foundation for further research on the mechanisms of molecular interactions and the integrated functions of Cocoa tea.

  17. Evolution of the distribution of tropospheric chemical species during the past decade

    NASA Astrophysics Data System (ADS)

    D'Angiola, Ariela; Granier, Claire; Bessagnet, Bertrand; Heil, Angelika; Khokhar, Fahim; Guenther, Alex; Jean-Francois, Lamarque; Meleux, Frederik; Mieville, Aude; Rouil, Laurence

    2010-05-01

    . Simulations covering the considered period will be performed using different combinations of the emissions of the datasets being performed. We will discuss the results of the simulations, focusing more particularly on the simulations using either IPCC dataset or a combined IPCC / European emissions dataset, or different Biogenic Volatile Organic Compounds emissions. We will discuss the changes in the distribution of tropospheric chemical species from the different simulations, considering both gaseous compounds and different types of aerosols.

  18. Divergent Chemical Cues Elicit Seed Collecting by Ants in an Obligate Multi-Species Mutualism in Lowland Amazonia

    PubMed Central

    Youngsteadt, Elsa; Guerra Bustios, Patricia; Schal, Coby

    2010-01-01

    In lowland Amazonian rainforests, specific ants collect seeds of several plant species and cultivate them in arboreal carton nests, forming species-specific symbioses called ant-gardens (AGs). In this obligate mutualism, ants depend on the plants for nest stability and the plants depend on ant nests for substrate and nutrients. AG ants and plants are abundant, dominant members of lowland Amazonian ecosystems, but the cues ants use to recognize the seeds are poorly understood. To address the chemical basis of the ant-seed interaction, we surveyed seed chemistry in nine AG species and eight non-AG congeners. We detected seven phenolic and terpenoid volatiles common to seeds of all or most of the AG species, but a blend of the shared compounds was not attractive to the AG ant Camponotus femoratus. We also analyzed seeds of three AG species (Anthurium gracile, Codonanthe uleana, and Peperomia macrostachya) using behavior-guided fractionation. At least one chromatographic fraction of each seed extract elicited retrieval behavior in C. femoratus, but the active fractions of the three plant species differed in polarity and chemical composition, indicating that shared compounds alone did not explain seed-carrying behavior. We suggest that the various AG seed species must elicit seed-carrying with different chemical cues. PMID:21209898

  19. Divergent chemical cues elicit seed collecting by ants in an obligate multi-species mutualism in lowland Amazonia.

    PubMed

    Youngsteadt, Elsa; Guerra Bustios, Patricia; Schal, Coby

    2010-12-30

    In lowland Amazonian rainforests, specific ants collect seeds of several plant species and cultivate them in arboreal carton nests, forming species-specific symbioses called ant-gardens (AGs). In this obligate mutualism, ants depend on the plants for nest stability and the plants depend on ant nests for substrate and nutrients. AG ants and plants are abundant, dominant members of lowland Amazonian ecosystems, but the cues ants use to recognize the seeds are poorly understood. To address the chemical basis of the ant-seed interaction, we surveyed seed chemistry in nine AG species and eight non-AG congeners. We detected seven phenolic and terpenoid volatiles common to seeds of all or most of the AG species, but a blend of the shared compounds was not attractive to the AG ant Camponotus femoratus. We also analyzed seeds of three AG species (Anthurium gracile, Codonanthe uleana, and Peperomia macrostachya) using behavior-guided fractionation. At least one chromatographic fraction of each seed extract elicited retrieval behavior in C. femoratus, but the active fractions of the three plant species differed in polarity and chemical composition, indicating that shared compounds alone did not explain seed-carrying behavior. We suggest that the various AG seed species must elicit seed-carrying with different chemical cues.

  20. What can decision analysis do for invasive species management?

    PubMed

    Maguire, Lynn A

    2004-08-01

    Decisions about management of invasive species are difficult for all the reasons typically addressed by multiattribute decision analysis: uncertain outcomes, multiple and conflicting objectives, and many interested parties with differing views on both facts and values. This article illustrates how the tools of multiattribute analysis can improve management of invasive species, with an emphasis on making explicit the social values and preferences that must inform invasive species management. Risk assessment protocols developed previously for invasive species management typically suffer from two interacting flaws: (1) separating risk assessment from risk management, thus disrupting essential connections between the social values at stake in invasive species decisions and the scientific knowledge necessary to predict the likely impacts of management actions, and (2) relying on expert judgment about risk framed in qualitative and value-laden terms, inadvertently mixing the expert's judgment about what is likely to happen with personal preferences. Using the values structuring and probability-modeling elements of formal decision analysis can remedy these difficulties and make invasive species management responsive to both good science and public values. The management of feral pigs in Hawaiian ecosystems illustrates the need for such an integrated approach.

  1. Species sensitivity analysis of heavy metals to freshwater organisms.

    PubMed

    Xin, Zheng; Wenchao, Zang; Zhenguang, Yan; Yiguo, Hong; Zhengtao, Liu; Xianliang, Yi; Xiaonan, Wang; Tingting, Liu; Liming, Zhou

    2015-10-01

    Acute toxicity data of six heavy metals [Cu, Hg, Cd, Cr(VI), Pb, Zn] to aquatic organisms were collected and screened. Species sensitivity distributions (SSD) curves of vertebrate and invertebrate were constructed by log-logistic model separately. The comprehensive comparisons of the sensitivities of different trophic species to six typical heavy metals were performed. The results indicated invertebrate taxa to each heavy metal exhibited higher sensitivity than vertebrates. However, with respect to the same taxa species, Cu had the most adverse effect on vertebrate, followed by Hg, Cd, Zn and Cr. When datasets from all species were included, Cu and Hg were still more toxic than the others. In particular, the toxicities of Pb to vertebrate and fish were complicated as the SSD curves of Pb intersected with those of other heavy metals, while the SSD curves of Pb constructed by total species no longer crossed with others. The hazardous concentrations for 5 % of the species (HC5) affected were derived to determine the concentration protecting 95 % of species. The HC5 values of the six heavy metals were in the descending order: Zn > Pb > Cr > Cd > Hg > Cu, indicating toxicities in opposite order. Moreover, potential affected fractions were calculated to assess the ecological risks of different heavy metals at certain concentrations of the selected heavy metals. Evaluations of sensitivities of the species at various trophic levels and toxicity analysis of heavy metals are necessary prior to derivation of water quality criteria and the further environmental protection.

  2. Terahertz Chemical Analysis of Exhaled Human Breath - Broad Essay of Chemicals

    NASA Astrophysics Data System (ADS)

    Branco, Daniela R.; Fosnight, Alyssa M.; Thomas, Jessica R.; Medvedev, Ivan R.

    2013-06-01

    Approximately 3000 chemicals are thought to be present in human breath. Of these chemicals, many are considered typical of exhaled air. Yet, others can allude to different disease pathologies. The detection of chemicals in breath could have many practical purposes in medicine and provide a noninvasive means of diagnostics. We have previously reported on detection of ethanol, methanol, and acetone in exhaled human breath using a novel sub-millimeter/THz spectroscopic approach. This paper reports on our most recent study. A tentative list has been made of approximately 20 chemicals previously found in breath using other methods. Though many of these chemicals are only expressed in samples from donors with certain pathologies, at the time of this submission we are able to detect and quantitatively measure acetaldehyde and dimethyl sulfide in the breath of several healthy donors. Additional tentatively identified chemicals have been seen using this approach. This presentation will explain our experimental procedures and present our most recent results in THz breath analysis. Prospects, challenges and future plans will be outlined and discussed.

  3. Airborne chemistry: acoustic levitation in chemical analysis.

    PubMed

    Santesson, Sabina; Nilsson, Staffan

    2004-04-01

    This review with 60 references describes a unique path to miniaturisation, that is, the use of acoustic levitation in analytical and bioanalytical chemistry applications. Levitation of small volumes of sample by means of a levitation technique can be used as a way to avoid solid walls around the sample, thus circumventing the main problem of miniaturisation, the unfavourable surface-to-volume ratio. Different techniques for sample levitation have been developed and improved. Of the levitation techniques described, acoustic or ultrasonic levitation fulfils all requirements for analytical chemistry applications. This technique has previously been used to study properties of molten materials and the equilibrium shape()and stability of liquid drops. Temperature and mass transfer in levitated drops have also been described, as have crystallisation and microgravity applications. The airborne analytical system described here is equipped with different and exchangeable remote detection systems. The levitated drops are normally in the 100 nL-2 microL volume range and additions to the levitated drop can be made in the pL-volume range. The use of levitated drops in analytical and bioanalytical chemistry offers several benefits. Several remote detection systems are compatible with acoustic levitation, including fluorescence imaging detection, right angle light scattering, Raman spectroscopy, and X-ray diffraction. Applications include liquid/liquid extractions, solvent exchange, analyte enrichment, single-cell analysis, cell-cell communication studies, precipitation screening of proteins to establish nucleation conditions, and crystallisation of proteins and pharmaceuticals.

  4. Pretreatment and integrated analysis of spectral data reveal seaweed similarities based on chemical diversity.

    PubMed

    Wei, Feifei; Ito, Kengo; Sakata, Kenji; Date, Yasuhiro; Kikuchi, Jun

    2015-03-03

    Extracting useful information from high dimensionality and large data sets is a major challenge for data-driven approaches. The present study was aimed at developing novel integrated analytical strategies for comprehensively characterizing seaweed similarities based on chemical diversity. The chemical compositions of 107 seaweed and 2 seagrass samples were analyzed using multiple techniques, including Fourier transform infrared (FT-IR) and solid- and solution-state nuclear magnetic resonance (NMR) spectroscopy, thermogravimetry-differential thermal analysis (TG-DTA), inductively coupled plasma-optical emission spectrometry (ICP-OES), CHNS/O total elemental analysis, and isotope ratio mass spectrometry (IR-MS). The spectral data were preprocessed using non-negative matrix factorization (NMF) and NMF combined with multivariate curve resolution-alternating least-squares (MCR-ALS) methods in order to separate individual component information from the overlapping and/or broad spectral peaks. Integrated analysis of the preprocessed chemical data demonstrated distinct discrimination of differential seaweed species. Further network analysis revealed a close correlation between the heavy metal elements and characteristic components of brown algae, such as cellulose, alginic acid, and sulfated mucopolysaccharides, providing a componential basis for its metal-sorbing potential. These results suggest that this integrated analytical strategy is useful for extracting and identifying the chemical characteristics of diverse seaweeds based on large chemical data sets, particularly complicated overlapping spectral data.

  5. Appendix C. Collection of Samples for Chemical Agent Analysis

    SciTech Connect

    Koester, C; Thompson, C; Doerr, T; Scripsick, R

    2005-09-23

    This chapter describes procedures for the collection and analysis of samples of various matrices for the purpose of determining the presence of chemical agents in a civilian setting. This appendix is intended to provide the reader with sufficient information to make informed decisions about the sampling and analysis process and to suggest analytical strategies that might be implemented by the scientists performing sampling and analysis. This appendix is not intended to be used as a standard operating procedure to provide detailed instructions as to how trained scientists should handle samples. Chemical agents can be classified by their physical and chemical properties. Table 1 lists the chemical agents considered by this report. In selecting sampling and analysis methods, we have considered procedures proposed by the Organization for Prohibition of Chemical Weapons (OPCW), the U. S. Environmental Protection Agency (EPA), and peer-reviewed scientific literature. EPA analytical methods are good resources describing issues of quality assurance with respect to chain-of-custody, sample handling, and quality control requirements.

  6. Chemical composition and antioxidant and anticandidal activities of essential oils from different wild Moroccan Thymus species.

    PubMed

    Jamali, Chaima Alaoui; El Bouzidi, Laila; Bekkouche, Khalid; Lahcen, Hassani; Markouk, Mohammed; Wohlmuth, Hans; Leach, David; Abbad, Abdelaziz

    2012-06-01

    Samples of the aerial parts of Thymus broussonetii, T. ciliatus, T. leptobotrys, T. maroccanus, T. pallidus, T. satureioides, and T. serpyllum collected from different natural regions in southern and south-western Morocco were analyzed for their qualitative and quantitative essential oil profiles. In total, 46 compounds, representing more than 99% of the oils, were characterized. Monoterpenes, both hydrocarbons (12.9-58.0%) and oxygenated monoterpenes (38.8-81.1%), were the principal classes of compounds for most of the thyme species studied. Cluster analysis allowed the classification of the species into three main groups: a carvacrol group (Group I), comprising the species T. maroccanus and T. leptobotrys, a linalyl acetate and (E)-nerolidol group (Group II), represented by T. serpyllum, and a thymol and/or carvacrol, γ-terpinene, and p-cymene group (Group III), composed of T. satureioides, T. broussonetii, T. ciliatus, and T. pallidus. The essential oils were screened for their antioxidant and anticandidal activities. The data showed that the oils obtained from T. leptobotrys and T. maroccanus (carvacrol group) possessed the highest antioxidant activities as assessed by the determination of the DPPH free radical-scavenging ability and the ferric-reducing potential. The anticandidal assays indicated that the highest activity was noticed for the essential oil isolated from T. leptobotrys.

  7. Chemical characterization of oligosaccharides in the milk of six species of New and Old world monkeys

    PubMed Central

    Goto, Kohta; Fukuda, Kenji; Senda, Akitsugu; Saito, Tadao; Kimura, Kazumasa; Glander, Kenneth E.; Hinde, Katie; Dittus, Wolfgang; Milligan, Lauren A.; Power, Michael L.; Oftedal, Olav T.

    2010-01-01

    Human and great ape milks contain a diverse array of milk oligosaccharides, but little is known about the milk oligosaccharides of other primates, and how they differ among taxa. Neutral and acidic oligosaccharides were isolated from the milk of three species of Old World or catarrhine monkeys (Cercopithecidae: rhesus macaque (Macaca mulatta), toque macaque (Macaca sinica) and Hamadryas baboon (Papio hamadryas)) and three of New World or platyrrhine monkeys (Cebidae: tufted capuchin (Cebus apella) and Bolivian squirrel monkey (Saimiri boliviensis); Atelidae: mantled howler (Alouatta palliata)). The milks of these species contained 6–8% total sugar, most of which was lactose: the estimated ratio of oligosaccharides to lactose in Old World monkeys (1:4 to 1:6) was greater than in New World monkeys (1:12 to 1:23). The chemical structures of the oligosaccharides were determined mainly by 1H-NMR spectroscopy. Oligosaccharides containing the type II unit (Gal(β1-4)GlcNAc) were found in the milk of the rhesus macaque, toque macaque, Hamadryas baboon and tufted capuchin, but oligosaccharides containing the type I unit (Gal(β1-3)GlcNAc), which have been found in human and many great ape milks, were absent from the milk of all species studied. Oligosaccharides containing Lewis x (Gal(β1-4)[Fuc(α1-3)]GlcNAc) and 3-fucosyl lactose (3-FL, Gal(β1-4)[Fuc(α1-3)]Glc) were found in the milk of the three cercopithecid monkey species, while 2-fucosyl lactose (5'-FL, Fuc(α1-2)Gal(β1-4)Glc) was absent from all species studied. All of these milks contained acidic oligosaccharides that had N-acetylneuraminic acid as part of their structures, but did not contain oligosaccharides that had N-glycolylneuraminic acid, in contrast to the milk or colostrum of great apes which contain both types of acidic oligosaccharides. Two GalNAc-containing oligosaccharides, lactose 3′-O-sulfate and lacto-N-novopentaose I (Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc) were found only in the

  8. Analysis of Chemical Bioactivity through In Vitro Profiling ...

    EPA Pesticide Factsheets

    Safety assessment of drugs and environmental chemicals relies extensively on animal testing. However, the quantity of chemicals needing assessment and challenges of species extrapolation drive the development of alternative approaches. The EPA’s ToxCast and the multiagency Tox21 programs address this through use of an extensive in vitro screening program to generate data on a large library of important environmental chemicals. These in vitro assays encompass both cell-free, biochemical assays targeting proteins that may be potential molecular initiating events and cellular assays that provide coverage of critical signaling pathways and toxicity phenotypes. Effects on model organisms such as the developing zebrafish, are also part of the testing strategy. A variety of computational approaches are used to analyze the resulting complex data sets to gain insight in to inherent biological activity of chemicals and possible mechanisms of toxicity. Several case studies including identification of modulators of estrogen receptor and aromatic hydrocarbon receptor pathways with effects in primary human cell systems will be described. In addition, existing in vivo data from a subset of the chemicals was used to anchor predictive models using in vitro data for a number of adverse endpoints including reproductive and developmental toxicities. The strengths and weaknesses of this approach will be described. This work does not necessarily reflect official Agency policy. Pres

  9. Chemically pre-strained dielectric elastomers finite element analysis

    NASA Astrophysics Data System (ADS)

    Newell, Brittany; Krutz, Gary; Stewart, Frank; Pascal, Kevin

    2017-04-01

    The applications and feasibility of utilizing dielectric elastomer electroactive polymers in the industrial and medical sectors has drastically increased in recent years due to significant improvements in actuation potential, manufacturing, the introduction of new materials and modeling capabilities. One such development is the introduction of chemical pre-strain as a method of providing enhanced actuation. The purpose of this study was to utilize finite element analysis to analyze the mechanical actuation of an industrial fluoropolymer with chemical induced pre-strain and validate the model with experiential results. Results generated from the finite element analysis showed similar trends to results produced experimentally.

  10. Chemical Variation in a Dominant Tree Species: Population Divergence, Selection and Genetic Stability across Environments

    PubMed Central

    O’Reilly-Wapstra, Julianne M.; Miller, Alison M.; Hamilton, Matthew G.; Williams, Dean; Glancy-Dean, Naomi; Potts, Brad M.

    2013-01-01

    Understanding among and within population genetic variation of ecologically important plant traits provides insight into the potential evolutionary processes affecting those traits. The strength and consistency of selection driving variability in traits would be affected by plasticity in differences among genotypes across environments (G×E). We investigated population divergence, selection and environmental plasticity of foliar plant secondary metabolites (PSMs) in a dominant tree species, Eucalyptus globulus. Using two common garden trials we examined variation in PSMs at multiple genetic scales; among 12 populations covering the full geographic range of the species and among up to 60 families within populations. Significant genetic variation in the expression of many PSMs resides both among and within populations of E. globulus with moderate (e.g., sideroxylonal A h2op = 0.24) to high (e.g., macrocarpal G h2op = 0.48) narrow sense heritabilities and high coefficients of additive genetic variation estimated for some compounds. A comparison of Qst and Fst estimates suggest that variability in some of these traits may be due to selection. Importantly, there was no genetic by environment interaction in the expression of any of the quantitative chemical traits despite often significant site effects. These results provide evidence that natural selection has contributed to population divergence in PSMs in E. globulus, and identifies the formylated phloroglucinol compounds (particularly sideroxylonal) and a dominant oil, 1,8-cineole, as candidates for traits whose genetic architecture has been shaped by divergent selection. Additionally, as the genetic differences in these PSMs that influence community phenotypes is stable across environments, the role of plant genotype in structuring communities is strengthened and these genotypic differences may be relatively stable under global environmental changes. PMID:23526981

  11. Chemical Composition, Nitrogen Fractions and Amino Acids Profile of Milk from Different Animal Species

    PubMed Central

    Rafiq, Saima; Huma, Nuzhat; Pasha, Imran; Sameen, Aysha; Mukhtar, Omer; Khan, Muhammad Issa

    2016-01-01

    Milk composition is an imperative aspect which influences the quality of dairy products. The objective of study was to compare the chemical composition, nitrogen fractions and amino acids profile of milk from buffalo, cow, sheep, goat, and camel. Sheep milk was found to be highest in fat (6.82%±0.04%), solid-not-fat (11.24%±0.02%), total solids (18.05%±0.05%), protein (5.15%±0.06%) and casein (3.87%±0.04%) contents followed by buffalo milk. Maximum whey proteins were observed in camel milk (0.80%±0.03%), buffalo (0.68%±0.02%) and sheep (0.66%±0.02%) milk. The non-protein-nitrogen contents varied from 0.33% to 0.62% among different milk species. The highest r-values were recorded for correlations between crude protein and casein in buffalo (r = 0.82), cow (r = 0.88), sheep (r = 0.86) and goat milk (r = 0.98). The caseins and whey proteins were also positively correlated with true proteins in all milk species. A favorable balance of branched-chain amino acids; leucine, isoleucine, and valine were found both in casein and whey proteins. Leucine content was highest in cow (108±2.3 mg/g), camel (96±2.2 mg/g) and buffalo (90±2.4 mg/g) milk caseins. Maximum concentrations of isoleucine, phenylalanine, and histidine were noticed in goat milk caseins. Glutamic acid and proline were dominant among non-essential amino acids. Conclusively, current exploration is important for milk processors to design nutritious and consistent quality end products. PMID:26954163

  12. Preference and aversion for deterrent chemicals in two species of Peromyscus mouse.

    PubMed

    Glendinning, J I

    1993-07-01

    Deterrent chemicals such as quinine hydrochloride (QHC1) are generally considered to be aversive to mammals at all detectable concentrations. However, several species contain individuals that drink solutions containing low concentrations of deterrents in preference to plain water. The present study examines this paradoxical preference in two species of mouse, Peromyscus melanotis and P. aztecus. Preliminary findings had suggested that whereas some P. aztecus prefer low concentrations of QHC1, no P. melanotis prefer any concentration of QHC1. Experiment 1 tested the hypothesis that individual mice that prefer low concentrations of QHC1 would respond similarly to four other deterrents described by humans as bitter and/or astringent (ouabain, hop extract, sucrose octaacetate, and tannic acid) in 48-h, two-bottle choice tests. Peromyscus aztecus displayed a large amount of intraspecific variation in response to all five deterrents. Those P. aztecus that drank low concentrations of QHC1 in preference to plain water were significantly more likely to respond similarly to low concentrations of the other deterrents. No P. melanotis displayed a preference for any concentration of either deterrent. Experiment 2 examined the temporal stability of the response to 0.1 mM QHC1 in P. aztecus over six consecutive choice tests. Mice were divided into three groups based on their initial response to the QHC1 solution (preference, no response, or rejection) and then subjected to the 12-day test. The response of mice within each of the groups did not change significantly over time.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. Chemical variation in a dominant tree species: population divergence, selection and genetic stability across environments.

    PubMed

    O'Reilly-Wapstra, Julianne M; Miller, Alison M; Hamilton, Matthew G; Williams, Dean; Glancy-Dean, Naomi; Potts, Brad M

    2013-01-01

    Understanding among and within population genetic variation of ecologically important plant traits provides insight into the potential evolutionary processes affecting those traits. The strength and consistency of selection driving variability in traits would be affected by plasticity in differences among genotypes across environments (G×E). We investigated population divergence, selection and environmental plasticity of foliar plant secondary metabolites (PSMs) in a dominant tree species, Eucalyptus globulus. Using two common garden trials we examined variation in PSMs at multiple genetic scales; among 12 populations covering the full geographic range of the species and among up to 60 families within populations. Significant genetic variation in the expression of many PSMs resides both among and within populations of E. globulus with moderate (e.g., sideroxylonal A h(2)op = 0.24) to high (e.g., macrocarpal G h(2)op = 0.48) narrow sense heritabilities and high coefficients of additive genetic variation estimated for some compounds. A comparison of Qst and Fst estimates suggest that variability in some of these traits may be due to selection. Importantly, there was no genetic by environment interaction in the expression of any of the quantitative chemical traits despite often significant site effects. These results provide evidence that natural selection has contributed to population divergence in PSMs in E. globulus, and identifies the formylated phloroglucinol compounds (particularly sideroxylonal) and a dominant oil, 1,8-cineole, as candidates for traits whose genetic architecture has been shaped by divergent selection. Additionally, as the genetic differences in these PSMs that influence community phenotypes is stable across environments, the role of plant genotype in structuring communities is strengthened and these genotypic differences may be relatively stable under global environmental changes.

  14. Chemical Composition and Biological Activity of Essential Oils from Different Species of Piper from Panama.

    PubMed

    Santana, Ana I; Vila, Roser; Cañigueral, Salvador; Gupta, Mahabir P

    2016-07-01

    The chemical composition of leaf essential oils from 11 species of Piper from Panama was analyzed by a combination GC-FID and GC-MS procedures. Six of them had sesquiterpene hydrocarbons as major constituents, three were characterized by monoterpene hydrocarbons, one by a diterpene, and one by a phenylpropanoid, dillapiole. The main components identified in each species were: cembratrienol (25.4 %) in Piper augustum; β-pinene (26.6 %) in Piper corrugatum; α-pinene (19.4 %) in Piper curtispicum; trans-β-farnesene (63.7 %) in Piper darienense; p-cymene (43.9 %) in Piper grande; dillapiole (57.7 %) in Piper hispidum; linalool (14.5 %), α-phellandrene (13.8 %), and limonene (12.2 %) in Piper jacquemontianum; β-caryophyllene (45.2 %) in Piper longispicum; linalool (16.5 %), α-phellandrene (11.8 %), limonene (11.4 %), and p-cymene (9.0 %) in Piper multiplinervium; β-selinene (19.0 %), β-elemene (16.1 %), and α-selinene (15.5 %) in Piper reticulatum; and germacrene D (19.7 %) in Piper trigonum. The essential oils of P. hispidum and P. longispicum at a concentration of 250 µg/mL showed larvicidal activity against Aedes aegypti, while the oils from P. curtispicum, P. multiplinervium, P. reticulatum, and P. trigonum were inactive (LC100 ≥ 500 µg/mL). The essential oils of P. grande, P. jacquemontianum, and P. multiplinervium showed no significant antifungal activity (MIC > 250 µg/mL) against several yeasts and filamentous fungal strains. Georg Thieme Verlag KG Stuttgart · New York.

  15. Chemical Analysis for Transient Response of Semiconductor Sensor by Autoregressive Model

    NASA Astrophysics Data System (ADS)

    Seto, Shuichi; Kawabe, Hiroyuki; Shimomura, Yuko; Shi, Liqin; Katsube, Teruaki; Oyabu, Takashi

    The objective of this study is qualitative and quantitative analysis of chemical species reacting to surface of semiconductor sensors. In ordinal studies on detection of gas species by semiconductor sensors, researchers attach importance to the chemical sensitivity of sensors and notice the output value of sensors in the stationary state of the response characteristics. However, the response in the transient state, i.e., the region between the beginning of reaction and the equilibrium of reaction, has much information of chemical processes of gases reacting to surface of sensor. Hence, in this study, we adopt an autoregressive (AR) model in which the parameters describing exponential curves are looked for. As a procedure, we construct a model of reaction on the surface of sensor and assume it as the first order reaction in gas molecule. We simulate the chemical processes mathematically, and apply the AR model on the signal. Then, we reproduce the reaction rate constants and the initial amplitudes and identify the species of gases.

  16. Cytotaxonomical analysis of Momordica L. (Cucurbitaceae) species of Indian occurrence.

    PubMed

    Bharathi, L K; Munshi, A D; Vinod; Chandrashekaran, Shanti; Behera, T K; Das, A B; John, K Joseph; Vishalnath

    2011-04-01

    Somatic chromosome number and detailed karyotype analysis were carried out in six Indian Momordica species viz. M. balsamina, M. charantia, M. cochinchinensis, M. dioica, M. sahyadrica and M. cymbalaria (syn. Luffa cymbalaria; a taxon of controversial taxonomic identity). The somatic chromosome number 2n = 22 was reconfirmed in monoecious species (M. balsamina and M. charantia). Out of four dioecious species, the chromosome number was reconfirmed in M. cochinchinensis (2n = 28), M. dioica (2n = 28) and M. subangulata subsp. renigera (2n = 56), while in M. sahyadrica (2n = 28) somatic chromosome number was reported for the first time. A new chromosome number of 2n = 18 was reported in M. cymbalaria against its previous reports of 2n = 16, 22. The karyotype analysis of all the species revealed significant numerical and structural variations of chromosomes. It was possible to distinguish chromosomes of M. cymbalaria from other Momordica species and also between monoecious and dioecious taxa of the genus. Morphology and crossability among the dioecious species was also studied. Evidence from morphology, crossability, pollen viability and chromosome synapsis suggests a segmental allopolyploid origin for M. subangulata subsp. renigera. The taxonomic status of the controversial taxon M. cymbalaria was also discussed using morphological, karyological and crossability data.

  17. The in vitro pharmacological activities and a chemical investigation of three South African Salvia species.

    PubMed

    Kamatou, G P P; Viljoen, A M; Gono-Bwalya, A B; van Zyl, R L; van Vuuren, S F; Lourens, A C U; Başer, K H C; Demirci, B; Lindsey, K L; van Staden, J; Steenkamp, P

    2005-12-01

    Salvia species (sage) are well known in folk medicine throughout the world. In South Africa sage is used against fever and digestive disorders. Three closely related South African species (Salvia stenophylla, Salvia repens and Salvia runcinata) were investigated for their anti-oxidant (DPPH assay); anti-inflammatory (5-lipoxygenase and cyclo-oxygenase assays); antimalarial (tritiated hypoxanthine incorporation assay); antimicrobial (disc diffusion and micro-dilution assays) properties and toxicity profile (tetrazolium-based assay). The solvent extracts exhibited anti-oxidant, antimalarial and antibacterial and poor anti-inflammatory properties. The essential oils exhibited anti-inflammatory and antimalarial properties, but displayed poor anti-oxidant and antimicrobial activity. The extract of Salviastenophylla and the essential oil of Salvia runcinata displayed the highest toxicity profile. Overall, Salvia runcinata displayed the most favorable activity of all three taxa tested with an IC(50) value of 6.09 (anti-oxidant); 29.05 (antimalarial) and 22.82 microg/ml (anti-inflammatory). Analytical procedures (GC-MS and HPLC-UV) were employed to generate chromatographic profiles for the essential oils and solvent extracts respectively. The HPLC analysis revealed the presence of rosmarinic acid in all three taxa while carnosic acid was only present in Salvia repens and Salvia stenophylla. The GC-MS analysis showed that oils were qualitatively and quantitatively variable. beta-Caryophyllene was present in large amounts in all three taxa. Other components present include camphor, alpha-pinene and alpha-bisabolol. The results of the in vitro pharmacological activities provide a scientific basis to validate the use of these Salvia species in traditional medicine in South Africa.

  18. Analysis of the parasitic copepod species richness among Mediterranean fish

    NASA Astrophysics Data System (ADS)

    Raibaut, André; Combes, Claude; Benoit, Françoise

    1998-06-01

    The Mediterranean ichthyofauna is composed of 652 species belonging to 405 genera and 117 families. Among these, 182 were studied for their parasitic copepods. The analysis of all the works conducted on these crustacea yielded 226 species distributed in 88 genera and 20 families. For each fish species we have established a file providing the species name of the fish, its family, its geographical distribution within the Mediterranean and some of its bio-ecological characteristics. Within each file, all the parasitic copepod species reported on each host species were listed. This allowed to know the species richness (SR) of these hosts. We thus produced 182 files within which 226 copepod species are distributed. A program was created under the Hypercard software, in order to analyse our data. Two parameters were studied. The first one is the mean species richness (MSR), which corresponds to the mean of the different SR found on the different host species. The second is the parasite-host ratio (P/H), which is the ratio of the number of copepod species by the number of host species. These parameters are calculated by our program for all the 182 species of Mediterranean fishes retained in our investigation, on the first hand, and, on the second hand, for one particular group of fish species. We used the following variables to investigate their correlations with copepod species richness: taxonomy—fish families, genera and species; biometry—maximal size of the adult fish; eco-ethology—mode of life (benthic, pelagic or nectonic), displacements (sedentary, migratory with environmental change, or migratory without environmental change), behaviour (solitary or gregarious). Other variables (colour, food, reproduction, abundance, distribution area) were also analysed but did not reveal any clear correlation. Providing that our study does not rely on quantitative (prevalence, intensity) but qualitative basis our aim was only to reveal some tendencies. These tendencies are

  19. ANALYSIS OF SAMPLES FROM TANK 5F CHEMICAL CLEANING

    SciTech Connect

    Poirier, M.; Fink, S.

    2011-03-07

    The Savannah River Site (SRS) is preparing Tank 5F for closure. The first step in preparing the tank for closure is mechanical sludge removal. Following mechanical sludge removal, SRS performed chemical cleaning with oxalic acid to remove the sludge heel. Personnel are currently assessing the effectiveness of the chemical cleaning. SRS personnel collected liquid samples during chemical cleaning and submitted them to Savannah River National Laboratory (SRNL) for analysis. Following chemical cleaning, they collected a solid sample (also known as 'process sample') and submitted it to SRNL for analysis. The authors analyzed these samples to assess the effectiveness of the chemical cleaning process. The conclusions from this work are: (1) With the exception of iron, the dissolution of sludge components from Tank 5F agreed with results from the actual waste demonstration performed in 2007. The fraction of iron removed from Tank 5F by chemical cleaning was significantly less than the fraction removed in the SRNL demonstrations. The likely cause of this difference is the high pH following the first oxalic acid strike. (2) Most of the sludge mass remaining in the tank is iron and nickel. (3) The remaining sludge contains approximately 26 kg of barium, 37 kg of chromium, and 37 kg of mercury. (4) Most of the radioactivity remaining in the residual material is beta emitters and {sup 90}Sr. (5) The chemical cleaning removed more than {approx} 90% of the uranium isotopes and {sup 137}Cs. (6) The chemical cleaning removed {approx} 70% of the neptunium, {approx} 83% of the {sup 90}Sr, and {approx} 21% of the {sup 60}Co. (7) The chemical cleaning removed less than 10% of the plutonium, americium, and curium isotopes. (8) The chemical cleaning removed more than 90% of the aluminium, calcium, and sodium from the tank. (9) The cleaning operations removed 61% of lithium, 88% of non-radioactive strontium, and 65% of zirconium. The {sup 90}Sr and non-radioactive strontium were measured

  20. ESTIMATION OF CHEMICAL TOXICITY TO WILDLIFE SPECIES USING INTERSPECIES CORRELATION MODELS

    EPA Science Inventory

    Ecological risks to wildlife are typically assessed using toxicity data for relataively few species and with limited understanding of differences in species sensitivity to contaminants. Empirical interspecies correlation models were derived from LD50 values for 49 wildlife speci...

  1. ESTIMATION OF CHEMICAL TOXICITY TO WILDLIFE SPECIES USING INTERSPECIES CORRELATION MODELS

    EPA Science Inventory

    Ecological risks to wildlife are typically assessed using toxicity data for relataively few species and with limited understanding of differences in species sensitivity to contaminants. Empirical interspecies correlation models were derived from LD50 values for 49 wildlife speci...

  2. Assessing Contaminant Sensitivity of Endangered and Threatened Aquatic Species: Part I. Acute Toxicity of Five Chemicals

    EPA Science Inventory

    This paper reports on the results of acute toxicity tests conducted with common surrogate species, and several species of threatened and endangered species for which there were excess artificially propagated stock to allow direct testing.

  3. Assessing Contaminant Sensitivity of Endangered and Threatened Aquatic Species: Part I. Acute Toxicity of Five Chemicals

    EPA Science Inventory

    This paper reports on the results of acute toxicity tests conducted with common surrogate species, and several species of threatened and endangered species for which there were excess artificially propagated stock to allow direct testing.

  4. Micropyrolyzer for chemical analysis of liquid and solid samples

    DOEpatents

    Mowry, Curtis D.; Morgan, Catherine H.; Manginell, Ronald P.; Frye-Mason, Gregory C.

    2006-07-18

    A micropyrolyzer has applications to pyrolysis, heated chemistry, and thermal desorption from liquid or solid samples. The micropyrolyzer can be fabricated from semiconductor materials and metals using standard integrated circuit technologies. The micropyrolyzer enables very small volume samples of less than 3 microliters and high sample heating rates of greater than 20.degree. C. per millisecond. A portable analyzer for the field analysis of liquid and solid samples can be realized when the micropyrolyzer is combined with a chemical preconcentrator, chemical separator, and chemical detector. Such a portable analyzer can be used in a variety of government and industrial applications, such as non-proliferation monitoring, chemical and biological warfare detection, industrial process control, water and air quality monitoring, and industrial hygiene.

  5. Surface chemical composition analysis of heat-treated bamboo

    NASA Astrophysics Data System (ADS)

    Meng, Fan-dan; Yu, Yang-lun; Zhang, Ya-mei; Yu, Wen-ji; Gao, Jian-min

    2016-05-01

    In this study, the effect of heat treatment on the chemical composition of bamboo slivers was studied. The chemical properties of the samples were examined by chemical analysis. Results showed a decrease in the contents of holocellulose and α-cellulose, as well as an increase in the contents of lignin and extractives. Changes in the chemical structure of bamboo components were analyzed by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). FTIR spectroscopy results indicated that hemicellulose contents decrease, whereas lignin contents increase after heat treatment. Ester formation linked to lignin decreased the hygroscopicity of the bamboo samples and consequently improved their dimensional stability and durability. XPS spectroscopy results showed that hemicelluloses and celluloses are relatively more sensitive to the heating process than lignin. As a consequence, hemicellulose and cellulose contents decreased, whereas lignin contents increased during heat treatment. The results obtained in this study provide useful information for the future utilization of heat-treated bamboo.

  6. An Inverse Analysis Approach to the Characterization of Chemical Transport in Paints

    PubMed Central

    Willis, Matthew P.; Stevenson, Shawn M.; Pearl, Thomas P.; Mantooth, Brent A.

    2014-01-01

    The ability to directly characterize chemical transport and interactions that occur within a material (i.e., subsurface dynamics) is a vital component in understanding contaminant mass transport and the ability to decontaminate materials. If a material is contaminated, over time, the transport of highly toxic chemicals (such as chemical warfare agent species) out of the material can result in vapor exposure or transfer to the skin, which can result in percutaneous exposure to personnel who interact with the material. Due to the high toxicity of chemical warfare agents, the release of trace chemical quantities is of significant concern. Mapping subsurface concentration distribution and transport characteristics of absorbed agents enables exposure hazards to be assessed in untested conditions. Furthermore, these tools can be used to characterize subsurface reaction dynamics to ultimately design improved decontaminants or decontamination procedures. To achieve this goal, an inverse analysis mass transport modeling approach was developed that utilizes time-resolved mass spectroscopy measurements of vapor emission from contaminated paint coatings as the input parameter for calculation of subsurface concentration profiles. Details are provided on sample preparation, including contaminant and material handling, the application of mass spectrometry for the measurement of emitted contaminant vapor, and the implementation of inverse analysis using a physics-based diffusion model to determine transport properties of live chemical warfare agents including distilled mustard (HD) and the nerve agent VX. PMID:25226346

  7. An inverse analysis approach to the characterization of chemical transport in paints.

    PubMed

    Willis, Matthew P; Stevenson, Shawn M; Pearl, Thomas P; Mantooth, Brent A

    2014-08-29

    The ability to directly characterize chemical transport and interactions that occur within a material (i.e., subsurface dynamics) is a vital component in understanding contaminant mass transport and the ability to decontaminate materials. If a material is contaminated, over time, the transport of highly toxic chemicals (such as chemical warfare agent species) out of the material can result in vapor exposure or transfer to the skin, which can result in percutaneous exposure to personnel who interact with the material. Due to the high toxicity of chemical warfare agents, the release of trace chemical quantities is of significant concern. Mapping subsurface concentration distribution and transport characteristics of absorbed agents enables exposure hazards to be assessed in untested conditions. Furthermore, these tools can be used to characterize subsurface reaction dynamics to ultimately design improved decontaminants or decontamination procedures. To achieve this goal, an inverse analysis mass transport modeling approach was developed that utilizes time-resolved mass spectroscopy measurements of vapor emission from contaminated paint coatings as the input parameter for calculation of subsurface concentration profiles. Details are provided on sample preparation, including contaminant and material handling, the application of mass spectrometry for the measurement of emitted contaminant vapor, and the implementation of inverse analysis using a physics-based diffusion model to determine transport properties of live chemical warfare agents including distilled mustard (HD) and the nerve agent VX.

  8. Morphological analysis of the Chinese Cipangopaludina species (Gastropoda; Caenogastropoda: Viviparidae)

    PubMed Central

    LU, Hong-Fa; DU, Li-Na; LI, Zhi-Qiang; CHEN, Xiao-Yong; YANG, Jun-Xing

    2014-01-01

    Viviparidae are widely distributed around the globe, but there are considerable gaps in the taxonomic record. To date, 18 species of the viviparid genus Cipangopaludina have been recorded in China, but there is substantial disagreement on the validity of this taxonomy. In this study, we described the shell and internal traits of these species to better discuss the validity of related species. We found that C. ampulliformis is synonym of C. lecythis, and C. wingatei is synonym of C. chinensis, while C. ampullacea and C. fluminalis are subspecies of C. lecythis and C. chinensis, respectively. C. dianchiensis should be paled in the genus Margarya, while C. menglaensis and C. yunnanensis belong to genus Mekongia. Totally, this leaves 11 species and 2 subspecies recorded in China. Based on whether these specimens’ spiral whorl depth was longer than aperture depth, these species or subspecies can be further divided into two groups, viz. chinensis group and cathayensis group, which can be determined from one another via the ratio of spiral depth and aperture depth, vas deferens and number of secondary branches of vas deferens. Additionally, Principal Component Analysis indicated that body whorl depth, shell width, aperture width and aperture length were main variables during species of Cipangopaludina. A key to all valid Chinese Cipangopaludina species were given. PMID:25465086

  9. Molecular Analysis of Sarcoidosis Tissues for Mycobacterium Species DNA

    PubMed Central

    Pei, Zhiheng; Pride, David T.; Collins, Robert D.; Cover, Timothy L.; Blaser, Martin J.

    2002-01-01

    We performed polymerase chain reaction analysis, for Mycobacterium species 16S rRNA, rpoB, and IS6110 sequences, on 25 tissue specimens from patients with sarcoidosis and on 25 control tissue specimens consisting of mediastinal or cervical lymph nodes and lung biopsies. Mycobacterium species 16S rRNA sequences were amplified from 12 (48%) rpoB sequences from 6 (24%) of the sarcoidosis specimens. In total, 16S rRNA or rpoB sequences were amplified from 15 sarcoidosis specimens (60%) but were not detected in any of the control tissues (p=0.00002, Chi square). In three specimens, the sequences resembled Mycobacterium species other than M. tuberculosis. All specimens with sequences consistent with M. tuberculosis were negative for IS6110. We provide evidence that one of a variety of Mycobacterium species, especially organisms resembling M. tuberculosis, is found in most patients with sarcoidosis. PMID:12453366

  10. Species identification through mitochondrial rRNA genetic analysis

    PubMed Central

    Yang, Li; Tan, Zongqing; Wang, Daren; Xue, Ling; Guan, Min-xin; Huang, Taosheng; Li, Ronghua

    2014-01-01

    Inter-species and intraspecific variations in mitochondrial DNA (mtDNA) were observed in a bioinformatics analysis of the mitochondrial genomic sequences of 11 animal species. Some highly conserved regions were identified in the mitochondrial 12S and 16S ribosomal RNA (rRNA) genes of these species. To test whether these sequences are universally conserved, primers were designed to target the conserved regions of these two genes and were used to amplify DNA from 21 animal tissues, including two of unknown origin. By sequencing these PCR amplicons and aligning the sequences to a database of non-redundant nucleotide sequences, it was confirmed that these amplicons aligned specifically to mtDNA sequences from the expected species of origin. This molecular technique, when combined with bioinformatics, provides a reliable method for the taxonomic classification of animal tissues. PMID:24522485

  11. Classification of pollen species using autofluorescence image analysis.

    PubMed

    Mitsumoto, Kotaro; Yabusaki, Katsumi; Aoyagi, Hideki

    2009-01-01

    A new method to classify pollen species was developed by monitoring autofluorescence images of pollen grains. The pollens of nine species were selected, and their autofluorescence images were captured by a microscope equipped with a digital camera. The pollen size and the ratio of the blue to red pollen autofluorescence spectra (the B/R ratio) were calculated by image processing. The B/R ratios and pollen size varied among the species. Furthermore, the scatter-plot of pollen size versus the B/R ratio showed that pollen could be classified to the species level using both parameters. The pollen size and B/R ratio were confirmed by means of particle flow image analysis and the fluorescence spectra, respectively. These results suggest that a flow system capable of measuring both scattered light and the autofluorescence of particles could classify and count pollen grains in real time.

  12. Analysis of lidar systems for profiling aurorally excited molecular species.

    PubMed

    Collins, R L; Lummerzheim, D; Smith, R W

    1997-08-20

    We report a detailed analysis of lidar systems that profile aurorally excited molecular species in the upper mesosphere and lower thermosphere ( ~80 -300 km). Current profiling of this region is performed with incoherent scatter radars that determine the total electron and ion concentrations but not the individual species. Studies of the aeronomy of the thermosphere requires knowledge of the species present and their relative populations in the different vibrational and rotational states. We review the spectroscopy of nitrogen to determine an optimized lidar system. We combine these results with current auroral observations and models to determine the performance of an actual lidar system. The study shows that such systems can provide high-resolution (1 km, 100 s) measurements of these species with current laser technology.

  13. Spectral identity mapping for enhanced chemical image analysis

    NASA Astrophysics Data System (ADS)

    Turner, John F., II

    2005-03-01

    Advances in spectral imaging instrumentation during the last two decades has lead to higher image fidelity, tighter spatial resolution, narrower spectral resolution, and improved signal to noise ratios. An important sub-classification of spectral imaging is chemical imaging, in which the sought-after information from the sample is its chemical composition. Consequently, chemical imaging can be thought of as a two-step process, spectral image acquisition and the subsequent processing of the spectral image data to generate chemically relevant image contrast. While chemical imaging systems that provide turnkey data acquisition are increasingly widespread, better strategies to analyze the vast datasets they produce are needed. The Generation of chemically relevant image contrast from spectral image data requires multivariate processing algorithms that can categorize spectra according to shape. Conventional chemometric techniques like inverse least squares, classical least squares, multiple linear regression, principle component regression, and multivariate curve resolution are effective for predicting the chemical composition of samples having known constituents, but are less effective when a priori information about the sample is unavailable. To address these problems, we have developed a fully automated non-parametric technique called spectral identity mapping (SIMS) that reduces the dependence of spectral image analysis on training datasets. The qualitative SIMS method provides enhanced spectral shape specificity and improved chemical image contrast. We present SIMS results of infrared spectral image data acquired from polymer coated paper substrates used in the manufacture of pressure sensitive adhesive tapes. In addition, we compare the SIMS results to results from spectral angle mapping (SAM) and cosine correlation analysis (CCA), two closely related techniques.

  14. Sum over Histories Representation for Kinetic Sensitivity Analysis: How Chemical Pathways Change When Reaction Rate Coefficients Are Varied.

    PubMed

    Bai, Shirong; Davis, Michael J; Skodje, Rex T

    2015-11-12

    The sensitivity of kinetic observables is analyzed using a newly developed sum over histories representation of chemical kinetics. In the sum over histories representation, the concentrations of the chemical species are decomposed into the sum of probabilities for chemical pathways that follow molecules from reactants to products or intermediates. Unlike static flux methods for reaction path analysis, the sum over histories approach includes the explicit time dependence of the pathway probabilities. Using the sum over histories representation, the sensitivity of an observable with respect to a kinetic parameter such as a rate coefficient is then analyzed in terms of how that parameter affects the chemical pathway probabilities. The method is illustrated for species concentration target functions in H2 combustion where the rate coefficients are allowed to vary over their associated uncertainty ranges. It is found that large sensitivities are often associated with rate limiting steps along important chemical pathways or by reactions that control the branching of reactive flux.

  15. The Sum over Histories Representation for Kinetic Sensitivity Analysis: How Chemical Pathways Change when Reaction Rate Coefficients are Varied

    SciTech Connect

    Bai, Shirong; Davis, Michael J.; Skodje, Rex T.

    2015-11-12

    The sensitivity of kinetic observables is analyzed using a newly developed sum over histories representation of chemical kinetics. In the sum over histories representation, the concentrations of the chemical species are decomposed into the sum of probabilities for chemical pathways that follow molecules from reactants to products or intermediates. Unlike static flux methods for reaction path analysis, the sum over histories approach includes the explicit time dependence of the pathway probabilities. Using the sum over histories representation, the sensitivity of an observable with respect to a kinetic parameter such as a rate coefficient is then analyzed in terms of how that parameter affects the chemical pathway probabilities. The method is illustrated for species concentration target functions in H-2 combustion where the rate coefficients are allowed to vary over their associated uncertainty ranges. It is found that large sensitivities are often associated with rate limiting steps along important chemical pathways or by reactions that control the branching of reactive flux

  16. Separate evaluation of multiple film-forming species in chemical vapor deposition of SiC using high aspect-ratio microchannels

    NASA Astrophysics Data System (ADS)

    Shima, Kohei; Sato, Noboru; Funato, Yuichi; Fukushima, Yasuyuki; Momose, Takeshi; Shimogaki, Yukihiro

    2017-06-01

    The effect of multiple film-forming species on the film quality during chemical vapor deposition (CVD) of SiC from CH3SiCl3/H2 was examined by separating each species using high aspect-ratio (AR) parallel-plate microchannels. Profiles of the chemical and physical properties of the grown SiC films, including the composition, crystallinity and surface roughness, were characterized along the microchannel depth. The exceptionally high AR, which was typically more than 1{,}000:1, allowed film growth with a variety of film-forming species that significantly changed with depth. We were thus able to examine the effect of each film-forming species on film growth. The exceptionally large depth, which was typically centimeter-scale, allowed depth profile analysis using various kinds of film characterization techniques having large detection areas. For CVD SiC from CH3SiCl3/H2, multiple film-forming species with different sticking probabilities of 8 × 10-7, 1 × 10-4, and 2 × 10-2 provided almost the same film quality.

  17. 3D Visualization of Monte-Carlo Simulation's of HZE Track Structure and Initial Chemical Species

    NASA Technical Reports Server (NTRS)

    Plante, Ianik; Cucinotta, Francis A.

    2009-01-01

    Heavy ions biophysics is important for space radiation risk assessment [1] and hadron-therapy [2]. The characteristic of heavy ions tracks include a very high energy deposition region close to the track (<20 nm) denoted as the track core, and an outer penumbra region consisting of individual secondary electrons (6-rays). A still open question is the radiobiological effects of 6- rays relative to the track core. Of importance is the induction of double-strand breaks (DSB) [3] and oxidative damage to the biomolecules and the tissue matrix, considered the most important lesions for acute and long term effects of radiation. In this work, we have simulated a 56Fe26+ ion track of 1 GeV/amu with our Monte-Carlo code RITRACKS [4]. The simulation results have been used to calculate the energy depiction and initial chemical species in a "voxelized" space, which is then visualized in 3D. Several voxels with dose >1000 Gy are found in the penumbra, some located 0.1 mm from the track core. In computational models, the DSB induction probability is calculated with radial dose [6], which may not take into account the higher RBE of electron track ends for DSB induction. Therefore, these simulations should help improve models of DSB induction and our understanding of heavy ions biophysics.

  18. 3D Visualization of Monte-Carlo Simulation's of HZE Track Structure and Initial Chemical Species

    NASA Technical Reports Server (NTRS)

    Plante, Ianik; Cucinotta, Francis A.

    2009-01-01

    Heavy ions biophysics is important for space radiation risk assessment [1] and hadron-therapy [2]. The characteristic of heavy ions tracks include a very high energy deposition region close to the track (<20 nm) denoted as the track core, and an outer penumbra region consisting of individual secondary electrons (6-rays). A still open question is the radiobiological effects of 6- rays relative to the track core. Of importance is the induction of double-strand breaks (DSB) [3] and oxidative damage to the biomolecules and the tissue matrix, considered the most important lesions for acute and long term effects of radiation. In this work, we have simulated a 56Fe26+ ion track of 1 GeV/amu with our Monte-Carlo code RITRACKS [4]. The simulation results have been used to calculate the energy depiction and initial chemical species in a "voxelized" space, which is then visualized in 3D. Several voxels with dose >1000 Gy are found in the penumbra, some located 0.1 mm from the track core. In computational models, the DSB induction probability is calculated with radial dose [6], which may not take into account the higher RBE of electron track ends for DSB induction. Therefore, these simulations should help improve models of DSB induction and our understanding of heavy ions biophysics.

  19. Using Temperature-Dependent Phenomena at Oxide Surfaces for Species Recognition in Chemical Sensing.

    NASA Astrophysics Data System (ADS)

    Semancik, Steve; Meier, Douglas; Evju, Jon; Benkstein, Kurt; Boger, Zvi; Montgomery, Chip

    2006-03-01

    Nanostructured films of SnO2 and TiO2 have been deposited on elements in MEMS arrays to fabricate solid state conductometric gas microsensors. The multilevel platforms within an array, called microhotplates, are individually addressable for localized temperature control and measurement of sensing film electrical conductance. Temperature variations of the microhotplates are employed in thermally-activated CVD oxide film growth, and for rapid temperature-programmed operation of the microsensors. Analytical information on environmental gas phase composition is produced temporally as purposeful thermal fluctuations provide energetic and kinetic control of surface reaction and adsorption/desorption phenomena. Resulting modulations of oxide adsorbate populations cause changing charge transfer behavior and measurable conductance responses. Rich data streams from different sensing films in the arrays have been analyzed by Artificial Neural Networks (ANN) to successfully recognize low concentration species in mixed gases. We illustrate capabilities of the approach and technology in the homeland security area, where dangerous chemicals (TICs, CWSs and CWAs) have been detected at 10-100 ppb levels in interference-spiked air backgrounds.

  20. Toxicological and chemical investigation of untreated municipal wastewater: Fraction- and species-specific toxicity.

    PubMed

    Hrubik, Jelena; Glisic, Branka; Tubic, Aleksandra; Ivancev-Tumbas, Ivana; Kovacevic, Radmila; Samardzija, Dragana; Andric, Nebojsa; Kaisarevic, Sonja

    2016-05-01

    Absence of a municipal wastewater (WW) treatment plant results in the untreated WW discharge into the recipient. The present study investigated toxic effects and chemical composition of water extracts and fractions from untreated WW and recipient Danube River (DR). Samples were prepared by solid-phase extraction and silica gel fractionation and screened for EROD activity and cytotoxicity using aquatic models, comprising of fish liver cells (PLHC-1) and a model of the early development of zebrafish embryos, while rat (H4IIE) and human (HepG2) hepatoma cells served as mammalian models. Polar fraction caused cytotoxicity and increased the EROD activity in PLHC-1 cells, and increased mortality and developmental abnormalities in developing zebrafish embryos. In H4IIE, polar fraction induced inhibition of cell growth and increased EROD activity, whereas HepG2 exerted low or no response to the exposure. Non-polar and medium-polar fractions were ineffective. Tentative identification by GC/MS showed that WW is characterized by the hydrocarbons, alkylphenols, plasticizers, and a certain number of benzene derivatives and organic acids. In DR, smaller number of organic compounds was identified and toxicity was less pronounced than in WW treatments. The present study revealed the potent toxic effect of polar fraction of untreated WW, with biological responses varying in sensitivity across organisms. Obtained results confirmed that fraction- and species-specific toxicity should be considered when assessing health risk of environmental pollution.

  1. Chemical Composition and Acetylcholinesterase Inhibitory Activity of Essential Oils from Piper Species.

    PubMed

    Xiang, Cai-Peng; Han, Jia-Xin; Li, Xing-Cong; Li, Yun-Hui; Zhang, Yi; Chen, Lin; Qu, Yan; Hao, Chao-Yun; Li, Hai-Zhou; Yang, Chong-Ren; Zhao, San-Jun; Xu, Min

    2017-05-10

    The essential oils (EOs) derived from aromatic plants such as Piper species are considered to play a role in alleviating neuronal ailments that are associated with inhibition of acetylcholinesterase (AChE). The chemical compositions of 23 EOs prepared from 16 Piper spp. were analyzed by both gas chromatography with a flame ionization detector (GC-FID) and gas chromatography-mass spectrometry (GC-MS). A total of 76 compounds were identified in the EOs from the leaves and stems of 19 samples, while 30 compounds were detected in the EOs from the fruits of four samples. Sesquiterpenes and phenylpropanoids were found to be rich in these EOs, of which asaricin, caryophyllene, caryophyllene oxide, isospathulenol, (+)-spathulenol, and β-bisabolene are the major constituents. The EOs from the leaves and stems of Piper austrosinense, P. puberulum, P. flaviflorum, P. betle, and P. hispidimervium showed strong AChE inhibitory activity with IC50 values in the range of 1.51 to 13.9 mg/mL. A thin-layer chromatography (TLC) bioautography assay was employed to identify active compound(s) in the most active EO from P. hispidimervium. The active compound was isolated and identified as asaricin, which gave an IC50 value of 0.44 ± 0.02 mg/mL against AChE, comparable to galantamine with an IC50 0.15 ± 0.01 mg/mL.

  2. Chemical constituents of the bark of Dipteryx alata vogel, an active species against Bothrops jararacussu venom.

    PubMed

    Puebla, Pilar; Oshima-Franco, Yoko; Franco, Luiz M; Santos, Marcio G Dos; Silva, Renata V da; Rubem-Mauro, Leandro; Feliciano, Arturo San

    2010-11-12

    The effect of four sub-extracts prepared from the lyophilized hydroalcoholic bark of Dipteryx alata (Leguminosae-Papilionoideae) dissolved in a methanol-water (80:20) mixture through a liquid-liquid partition procedure has been investigated against the neuromuscular blockade of the venom of the snake Bothrops jararacussu. The active CH₂Cl₂ sub-extract has been extensively analyzed for its chemical constituents, resulting in the isolation of four lupane-type triterpenoids: lupeol, lupenone, 28-hydroxylup-20(29)-en-3-one, betulin, nine isoflavonoids: 8-O-methylretusin, 7-hydroxy-5,6,4'-trimethoxyisoflavone, afrormosin, 7-hydroxy-8,3',4'-trimethoxyisoflavone, 7,3'-dihydroxy-8,4'-dimethoxyisoflavone, odoratin, 7,8,3'-trihydroxy-4'-methoxyisoflavone, 7,8,3'-trihydroxy-6,4'-dimethoxyisoflavone, dipteryxin, one chalcone: isoliquiritigenin, one aurone: sulfuretin and three phenolic compounds: vanillic acid, vanillin, and protocatechuic acid. Their chemical structures were elucidated on the basis of spectroscopic analysis, including HRMS, 1D- and 2D-NMR techniques.

  3. Null model analysis of species associations using abundance data.

    PubMed

    Ulrich, Werner; Gotelli, Nicholas J

    2010-11-01

    reinforces a previous meta-analysis of presence/absence matrices. However, using two of the metrics we detected a significant pattern of aggregation for plants and for the interaction matrices (which include plant-pollinator data sets). These results suggest that abundance matrices, analyzed with an appropriate null model, may be a powerful tool for quantifying patterns of species segregation and aggregation.

  4. Microfabricated devices for performing chemical and biochemical analysis

    SciTech Connect

    Ramsey, J.M.; Jacobson, S.C.; Foote, R.S.

    1997-05-01

    There is growing interest in microfabricated devices that perform chemical and biochemical analysis. The general goal is to use microfabrication tools to construct miniature devices that can perform a complete analysis starting with an unprocessed sample. Such devices have been referred to as lab-on-a-chip devices. Initial efforts on microfluidic laboratory-on-a-chip devices focused on chemical separations. There are many potential applications of these fluidic microchip devices. Some applications such as chemical process control or environmental monitoring would require that a chip be used over an extended period of time or for many analyses. Other applications such as forensics, clinical diagnostics, and genetic diagnostics would employ the chip devices as single use disposable devices.

  5. Computational singular perturbation analysis of stochastic chemical systems with stiffness

    NASA Astrophysics Data System (ADS)

    Wang, Lijin; Han, Xiaoying; Cao, Yanzhao; Najm, Habib N.

    2017-04-01

    Computational singular perturbation (CSP) is a useful method for analysis, reduction, and time integration of stiff ordinary differential equation systems. It has found dominant utility, in particular, in chemical reaction systems with a large range of time scales at continuum and deterministic level. On the other hand, CSP is not directly applicable to chemical reaction systems at micro or meso-scale, where stochasticity plays an non-negligible role and thus has to be taken into account. In this work we develop a novel stochastic computational singular perturbation (SCSP) analysis and time integration framework, and associated algorithm, that can be used to not only construct accurately and efficiently the numerical solutions to stiff stochastic chemical reaction systems, but also analyze the dynamics of the reduced stochastic reaction systems. The algorithm is illustrated by an application to a benchmark stochastic differential equation model, and numerical experiments are carried out to demonstrate the effectiveness of the construction.

  6. Welding fumes from stainless steel gas metal arc processes contain multiple manganese chemical species.

    PubMed

    Keane, Michael; Stone, Samuel; Chen, Bean

    2010-05-01

    Fumes from a group of gas metal arc welding (GMAW) processes used on stainless steel were generated using three different metal transfer modes and four different shield gases. The objective was to identify and measure manganese (Mn) species in the fumes, and identify processes that are minimal generators of Mn species. The robotic welding system was operated in short-circuit (SC) mode (Ar/CO2 and He/Ar), axial spray (AXS) mode (Ar/O2 and Ar/CO2), and pulsed axial-spray (PAXS) mode (Ar/O2). The fumes were analyzed for Mn by a sequential extraction process followed by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) analysis, and by X-ray diffraction (XRD). Total elemental Mn, iron (Fe), chromium (Cr) and nickel (Ni) were separately measured after aqua regia digestion and ICP-AES analysis. Soluble Mn2+, Fe2+, Fe3+, and Ni2+ in a simple biological buffer (phosphate-buffered saline) were determined at pH 7.2 and 5.0 after 2 h incubation at 37 C by ion chromatography. Results indicate that Mn was present in soluble form, acid-soluble form, and acid-soluble form after reduction by hydroxylamine, which represents soluble Mn0 and Mn2+ compounds, other Mn2+ compounds, and (Mn3+ and Mn4+) compounds, respectively. The dominant fraction was the acid-soluble Mn2+ fraction, but results varied with the process and shield gas. Soluble Mn mass percent in the fume ranged from 0.2 to 0.9%, acid-soluble Mn2+ compounds ranged from 2.6 to 9.3%, and acid plus reducing agent-soluble (Mn3+ and Mn4+) compounds ranged from 0.6 to 5.1%. Total Mn composition ranged from 7 to 15%. XRD results showed fumes had a crystalline content of 90-99% Fe3O4, and showed evidence of multiple Mn oxides, but overlaps and weak signals limited identification. Small amounts of the Mn2+ in the fume (<0.01 to ≈ 1% or <0.1 to ≈ 10 microg ml(-1)) and Ni2+ (<0.01 to ≈ 0.2% or <0.1 to ≈ 2 mg ml(-1)) ions were found in biological buffer media, but amounts were highly dependent on pH and the

  7. Variability of biomass chemical composition and rapid analysis using FT-NIR techniques

    SciTech Connect

    Liu, Lu; Ye, Philip; Womac, A.R.; Sokhansanj, Shahabaddine

    2010-04-01

    A quick method for analyzing the chemical composition of renewable energy biomass feedstock was developed by using Fourier transform near-infrared (FT-NIR) spectroscopy coupled with multivariate analysis. The study presents the broad-based model hypothesis that a single FT-NIR predictive model can be developed to analyze multiple types of biomass feedstock. The two most important biomass feedstocks corn stover and switchgrass were evaluated for the variability in their concentrations of the following components: glucan, xylan, galactan, arabinan, mannan, lignin, and ash. A hypothesis test was developed based upon these two species. Both cross-validation and independent validation results showed that the broad-based model developed is promising for future chemical prediction of both biomass species; in addition, the results also showed the method's prediction potential for wheat straw.

  8. Method for combined biometric and chemical analysis of human fingerprints.

    PubMed

    Staymates, Jessica L; Orandi, Shahram; Staymates, Matthew E; Gillen, Greg

    This paper describes a method for combining direct chemical analysis of latent fingerprints with subsequent biometric analysis within a single sample. The method described here uses ion mobility spectrometry (IMS) as a chemical detection method for explosives and narcotics trace contamination. A collection swab coated with a high-temperature adhesive has been developed to lift latent fingerprints from various surfaces. The swab is then directly inserted into an IMS instrument for a quick chemical analysis. After the IMS analysis, the lifted print remains intact for subsequent biometric scanning and analysis using matching algorithms. Several samples of explosive-laden fingerprints were successfully lifted and the explosives detected with IMS. Following explosive detection, the lifted fingerprints remained of sufficient quality for positive match scores using a prepared gallery consisting of 60 fingerprints. Based on our results (n = 1200), there was no significant decrease in the quality of the lifted print post IMS analysis. In fact, for a small subset of lifted prints, the quality was improved after IMS analysis. The described method can be readily applied to domestic criminal investigations, transportation security, terrorist and bombing threats, and military in-theatre settings.

  9. Application of risk assessment and decision analysis to aquatic nuisance species.

    PubMed

    Suedel, Burton C; Bridges, Todd S; Kim, Jongbum; Payne, Barry S; Miller, Andrew C

    2007-01-01

    The spread of nonindigenous (nonnative) species introduced into the United States is a significant and growing national problem and results in lost agricultural productivity, increased health problems, native species extinctions, and expensive prevention and eradication efforts. Thousands of nonindigenous species have either become established or spread, and introduction of aquatic nuisance species (ANS) into freshwater lakes threaten aquatic biodiversity. Expanding global trade is likely to increase the number of species that are spread across the globe, so the need to develop an approach to predict potential ANS invasions is great. Risk assessments currently being used to assess ANS risk rely on qualitative or semiquantitative information and expert opinion; thus, such approaches lack transparency and repeatability. A more quantitative approach is needed to augment the qualitative approaches currently in use. A quantitative approach with the use of the traditional ecological risk assessment (traditional ERA) framework combined with decision analysis tools was developed for assessing ANS risks in which the causative ecological risk agent is an organism rather than a chemical. This paper presents a systematic risk assessment framework that includes structured decision analysis to help organize and analyze pertinent data, state assumptions, address uncertainties in estimating the probability of an undesired ANS introduction, or spread and integrate these outputs with stakeholder values. This paper also describes when and how decision analysis tools can be used in such assessments for ANS. This framework and methodology will enable risk managers to systematically evaluate and compare alternatives and actions supporting ANS risk management and thus credibly prioritize resources.

  10. Spectangular - Spectral Disentangling For Detailed Chemical Analysis Of Binaries

    NASA Astrophysics Data System (ADS)

    Sablowski, Daniel

    2016-08-01

    Disentangling of spectra helps to improve the orbit parameters and allows detailed chemical analysis. Spectangular is a GUI program written in C++ for spectral disentangling of spectra of SB1 and SB2 systems. It is based on singular value decomposition in the wavelength space and is coupled to an orbital solution.The results are the component spectra and the orbital parameters.

  11. Rethinking the History of Artists' Pigments Through Chemical Analysis

    NASA Astrophysics Data System (ADS)

    Berrie, Barbara H.

    2012-07-01

    Following a brief overview of the history of analysis of artists' pigments, I discuss the illustrative example of lead-tin yellow. Recent advances in our knowledge of artists' use of red lakes, glassy pigments, and metallic pigments in works of cultural heritage, particularly European paintings, as determined from chemical analyses are described.

  12. Methods of chemical analysis used to characterize battery materials

    SciTech Connect

    Jensen, K. J.; Streets, W. E.

    1980-05-01

    Procedures are given for the chemical analysis of a variety of materials of interest in battery development and research. These materials include LiCl-KCl eutectic, Li-Al alloys, lithium sulfide, lithium aluminum chloride, calcium sulfide, titanium sulfide, and various sulfides of iron, nickel, copper, and cobalt. 8 tables.

  13. Systematic Approach for Calculating the Concentrations of Chemical Species in Multiequilibrium Problems: Inclusion of the Ionic Strength Effects

    ERIC Educational Resources Information Center

    Baeza-Baeza, Juan J.; Garcia-Alvarez-Coque, M. Celia

    2012-01-01

    A general systematic approach including ionic strength effects is proposed for the numerical calculation of concentrations of chemical species in multiequilibrium problems. This approach extends the versatility of the approach presented in a previous article and is applied using the Solver option of the Excel spreadsheet to solve real problems…

  14. SPECIES DIFFERENCES IN ANDROGEN AND ESTROGEN RECEPTOR STRUCTURE AND FUNCTION AMONG VERTEBRATES AND INVERTEBRATES: INTERSPECIES EXTRAPOLATIONS REGARDING ENDOCRINE DISRUPTING CHEMICALS

    EPA Science Inventory

    Species Differences in Androgen and Estrogen Receptor Structure and Function Among Vertebrates and Invertebrates: Interspecies Extrapolations regarding Endocrine Disrupting Chemicals
    VS Wilson1, GT Ankley2, M Gooding 1,3, PD Reynolds 1,4, NC Noriega 1, M Cardon 1, P Hartig1,...

  15. The effect of the electric wind on the spatial distribution of chemical species in the positive corona discharge

    NASA Astrophysics Data System (ADS)

    Yanallah, K.; Pontiga, F.; Bouazza, M. R.; Chen, J. H.

    2017-08-01

    The electrohydrodynamic air flow generated by a positive corona discharge, and its effect on the spatial distribution of chemical species within a wire-plate corona reactor, have been numerically simulated. The computational model is based on the solutions of the Navier-Stokes equation and the continuity equation of each chemical species generated by the electrical discharge. A simplified analytical expression of the electric force density, which only requires the current density as the input parameter, has been used in the Navier-Stokes equation to obtain the velocity field. For the solution of the continuity equations, a plasma chemistry model that includes the most important reactions between electrons, atoms and molecules in air has been used. Similar to the electric force, the electron density distribution has been approximated by using a semi-analytical expression appropriate for the electrode geometry. The results of the study show that the spatial distribution of chemical species can be very different, and depends on the interplay between the electrohydrodynamic flow, the chemical kinetics of the species and its characteristic lifetime.

  16. SPECIES DIFFERENCES IN ANDROGEN AND ESTROGEN RECEPTOR STRUCTURE AND FUNCTION AMONG VERTEBRATES AND INVERTEBRATES: INTERSPECIES EXTRAPOLATIONS REGARDING ENDOCRINE DISRUPTING CHEMICALS

    EPA Science Inventory

    Species Differences in Androgen and Estrogen Receptor Structure and Function Among Vertebrates and Invertebrates: Interspecies Extrapolations regarding Endocrine Disrupting Chemicals
    VS Wilson1, GT Ankley2, M Gooding 1,3, PD Reynolds 1,4, NC Noriega 1, M Cardon 1, P Hartig1,...

  17. Systematic Approach for Calculating the Concentrations of Chemical Species in Multiequilibrium Problems: Inclusion of the Ionic Strength Effects

    ERIC Educational Resources Information Center

    Baeza-Baeza, Juan J.; Garcia-Alvarez-Coque, M. Celia

    2012-01-01

    A general systematic approach including ionic strength effects is proposed for the numerical calculation of concentrations of chemical species in multiequilibrium problems. This approach extends the versatility of the approach presented in a previous article and is applied using the Solver option of the Excel spreadsheet to solve real problems…

  18. Physical and chemical characterization of biochars produced from coppiced wood of thirteen tree species for use in horticultural substrates

    USDA-ARS?s Scientific Manuscript database

    Seven-year-old coppiced shoots from thirteen species of native and non-native trees and shrubs were harvested, dried, and were pyrolyzed to produce biochars for potential use in horticultural substrates. Several chemical and physical characteristics of the biochars were determined. There were slight...

  19. Chemical Cues which Include Amino Acids Mediate Species-Specific Feeding Behavior in Invasive Filter-Feeding Bigheaded Carps.

    PubMed

    Claus, Aaron W; Sorensen, Peter W

    2017-03-15

    This study tested whether and how dissolved chemicals might assist food recognition in two filter-feeding fishes, the silver (Hypophthalmichthys molitrix) and the bighead carp (H. nobilis). These species evolved in Asia, are now invasive in the Mississippi River, and feed voraciously on microparticles including plankton. The food habits and biology of these carps are broadly similar to many filter-feeding fish, none of whose chemical ecology has been examined. We conducted five experiments. First, we demonstrated that buccal-pharngeal pumping (BPP), a behavior in which fish pump water into their buccal cavities, is responsible for sampling food: BPP activity in both silver and bighead carps was low and increased nearly 25-fold after exposure to a filtrate of a planktonic food mixture (P < 0.01) and over 35-fold when planktonic food was added (P < 0.001). Next, we showed that of nine food filtrates, the one containing chemicals released by spirulina, a type of cyanobacterium, was the most potent planktonic component for both species. The potency of filtrates varied between species in ways that reflected their different chemical compositions. While L-amino acids could explain about half of the activity of food filtrate, other unknown chemical stimuli were also implicated. Finally, occlusion experiments showed the olfactory sense has a very important, but not exclusive, role in bigheaded carp feeding behaviors and this might be exploited in both their control and culture.

  20. Take time to smell the frogs: vocal sac glands of reed frogs (Anura: Hyperoliidae) contain species-specific chemical cocktails

    PubMed Central

    Starnberger, Iris; Poth, Dennis; Peram, Pardha Saradhi; Schulz, Stefan; Vences, Miguel; Knudsen, Jette; Barej, Michael F; Rödel, Mark-Oliver; Walzl, Manfred; Hödl, Walter

    2013-01-01

    Males of all reed frog species (Anura: Hyperoliidae) have a prominent, often colourful, gular patch on their vocal sac, which is particularly conspicuous once the vocal sac is inflated. Although the presence, shape, and form of the gular patch are well-known diagnostic characters for these frogs, its function remains unknown. By integrating biochemical and histological methods, we found strong evidence that the gular patch is a gland producing volatile compounds, which might be emitted while calling. Volatile compounds were confirmed by gas chromatography–mass spectrometry in the gular glands in 11 species of the hyperoliid genera Afrixalus, Heterixalus, Hyperolius, and Phlyctimantis. Comparing the gular gland contents of 17 specimens of four sympatric Hyperolius species yielded a large variety of 65 compounds in species-specific combinations. We suggest that reed frogs might use a complex combination of at least acoustic and chemical signals in species recognition and mate choice. PMID:24277973

  1. Population viability analysis with species occurrence data from museum collections.

    PubMed

    Skarpaas, Olav; Stabbetorp, Odd E

    2011-06-01

    The most comprehensive data on many species come from scientific collections. Thus, we developed a method of population viability analysis (PVA) in which this type of occurrence data can be used. In contrast to classical PVA, our approach accounts for the inherent observation error in occurrence data and allows the estimation of the population parameters needed for viability analysis. We tested the sensitivity of the approach to spatial resolution of the data, length of the time series, sampling effort, and detection probability with simulated data and conducted PVAs for common, rare, and threatened species. We compared the results of these PVAs with results of standard method PVAs in which observation error is ignored. Our method provided realistic estimates of population growth terms and quasi-extinction risk in cases in which the standard method without observation error could not. For low values of any of the sampling variables we tested, precision decreased, and in some cases biased estimates resulted. The results of our PVAs with the example species were consistent with information in the literature on these species. Our approach may facilitate PVA for a wide range of species of conservation concern for which demographic data are lacking but occurrence data are readily available.

  2. Identification of sesquiterpene lactones in the Bryophyta (mosses) Takakia: Takakia species are closely related chemically to the Marchantiophyta (liverworts).

    PubMed

    Asakawa, Yoshinori; Nii, Kaeko; Higuchi, Masanobu

    2015-01-01

    Takakia lepidozioides has been considered to be the most primitive liverwort morphologically and classified initially in the Marchantiophyta (liverworts). However, the Takakia have been reclassified from liverworts to mosses on the basis of the similarity of the male sporophyte of T. ceratophylla to that of some mosses. Reinvestigation of secondary metabolites of fresh T. lepidozioides resulted in identification of eudesmane-type sesquiterpene lactones and hydrocarbon that are significant chemical markers of several liverworts. T. lepidozioides also produces a small amount of hop-22(29)-ene, together with coumarin, which produce the characteristic odor of T. lepidozioides, and 1,4-hydroquinone; these are the predominant volatile components, whereas dihydrocoumarin, 1,4-benzoquinone, dihydrobenzofuran, α-asarone and α-tocopherol are minor components. These chemical results indicated that T. lepidozioides is more closely related to the Marchantiophyta than the Bryophyta. T. lepidozioides is morphologically similar to the liverwort Haplomitrium species. However, both species are totally different chemically.

  3. Analysis of annual Medicago species using RAPD markers.

    PubMed

    Brummer, E C; Bouton, J H; Kochert, G

    1995-04-01

    Annual species of the genus Medicago have attracted interest as green manure and temporary forage crops. This study was conducted to determine if randomly amplified polymorphic DNA (RAPD) markers could be used to assess the variability within and among species. Several accessions of each six species (M. scutellata Mill., M. disciformis DC., M. murex Willd., M. truncatula Gaertn., M. polymorpha L., and M. rugosa Desr.) were studied. A phylogeny reconstructed with the computer program Phylogenetic Analysis Using Parsimony (PAUP) showed the same relationships as traditional taxonomy. Variation was present among accessions of all species. Several accessions were considerably different from others within the species (one of each M. scutellata and M. polymorpha) and four accessions of M. murex were differentiated by both morphology and RAPD banding patterns from the other accessions. These accessions may be useful to include in a core collection. Variation within accessions was present. Although the species are autogamous, the original seed collections may have been made from a number of plants in the same area. Also, some outcrossing or seed mixing may have occurred. Finally, at least 10 RAPD primers appear to be necessary in order to develop reliable estimates of relatedness among annual Medicago accessions.

  4. Chemical species separation with simultaneous estimation of field map and T2* using a k-space formulation.

    PubMed

    Honorato, Jose Luis; Parot, Vicente; Tejos, Cristian; Uribe, Sergio; Irarrazaval, Pablo

    2012-08-01

    Chemical species separation techniques in image space are prone to incorporate several distortions. Some of these are signal accentuation in borders and geometrical warping from field inhomogeneity. These errors come from neglecting intraecho time variations. In this work, we present a new approach for chemical species separation in MRI with simultaneous estimation of field map and T2* decay, formulated entirely in k-space. In this approach, the time map is used to model the phase accrual from off-resonance precession and also the amplitude decay due to T2*. Our technique fits the signal model directly in k-space with the acquired data minimizing the l(2)-norm with an interior-point algorithm. Standard two dimensional gradient echo sequences in the thighs and head were used for demonstrating the technique. With this approach, we were able to obtain excellent estimation for the species, the field inhomogeneity, and T2* decay images. The results do not suffer from geometric distortions derived from the chemical shift or the field inhomogeneity. Importantly, as the T2* map is well positioned, the species signal in borders is correctly estimated. Considering intraecho time variations in a complete signal model in k-space for separating species yields superior estimation of the variables of interest when compared to existing methods.

  5. Chemical Investigation of Some Capparis Species Growing in Egypt and their Antioxidant Activity

    PubMed Central

    Hamed, Ahmed R.; Abdel-Shafeek, Khaled A.; Abdel-Azim, Nahla S.; Ismail, Shams I.

    2007-01-01

    Capparis cartilaginea and C. deserti growing in Egypt were investigated for their glucosiolates and rutin content. From Capparis cartilaginea four isothiocynates were isolated and identified using GC and EI/MS techniques. These compounds were butyl isothiocyanate (1), 6-methylsulphonylhexyl isothiocyanate (2), 7-methylsulphonylheptyl isothiocyanate (3) and 5-benzylsulphonyl-4-pentenyl isothiocyanate (4). In addition to compounds (1) and (2), two other compounds were isolated and identified from Capparis deserti. These compounds are 3-methylthiopropyl isothiocyanate (5) and [11-(2-butenylthio)6-undecenyl isothiocyanate] (6). Compounds (1), (2), (5) and (6) are reported in this study for the first time from Capparis deserti. The main flavonoid component in the studied species was isolated and identified as rutin by comparing the data with those reported. Also, quantitative evaluation of rutin in the two species was carried out by TLC-densitometric analysis. The antioxidant activity was done using diphenylpicrylhydrazyl (DPPH) radical scavenging method. The butanol fraction from C. cartilaginea and C. deserti showed the highest antioxidant properties. PMID:18227928

  6. New materials and multidimensional cluster analysis for SAW chemical sensor arrays

    SciTech Connect

    Ricco, A.J.; Osbourn, G.C.; Bartholomew, J.W.; Crooks, R.M.; Chuanjing, Xu; Allred, R.E.

    1994-05-01

    We use six-element arrays of 97-MHz ST-quartz surface acoustic wave (SAW) devices to detect changes in thin-film mass and mechanical properties resulting from sorption of analytes by films representing two new classes of chemical sensor interface: self-assembled monolayers (SAMs) and plasma-grafted films (PGFs). While these materials do not display exceptional chemical selectivity, various combinations of the 7 different SAMs and 8 PGFs examined to produce distinct response patterns for each of 13 analytes. The analytes include aliphatic, aromatic, and chlorinated hydrocarbons; alcohols; ketones; organophosphonates; and water. Evaluation of the SAW array data using multidimensional cluster analysis techniques show that each chemical species can be correctly identified 100% of the time over the 9%- to 49%-of-saturation range using data from many combinations of four or more films.

  7. A rapid chemical method for lysing Arabidopsis cells for protein analysis.

    PubMed

    Tsugama, Daisuke; Liu, Shenkui; Takano, Tetsuo

    2011-07-15

    Protein extraction is a frequent procedure in biological research. For preparation of plant cell extracts, plant materials usually have to be ground and homogenized to physically break the robust cell wall, but this step is laborious and time-consuming when a large number of samples are handled at once. We developed a chemical method for lysing Arabidopsis cells without grinding. In this method, plants are boiled for just 10 minutes in a solution containing a Ca2+ chelator and detergent. Cell extracts prepared by this method were suitable for SDS-PAGE and immunoblot analysis. This method was also applicable to genomic DNA extraction for PCR analysis. Our method was applied to many other plant species, and worked well for some of them. Our method is rapid and economical, and allows many samples to be prepared simultaneously for protein analysis. Our method is useful not only for Arabidopsis research but also research on certain other species.

  8. Cumulative Index to Chemicals and to Common and Scientific Names of Species Listed in Contaminant Hazard Reviews 1 through 34

    USGS Publications Warehouse

    Eisler, R.

    1999-01-01

    The Patuxent Wildlife Research Center Contaminant Hazard Reviews (CHR) series synthesizes ecotoxicological data of selected environmental contaminants, with emphasis on hazards to native species of flora and fauna. From 1985 through 1998 a total of 34 reviews were published in various Reports series of the U.S. Department of the Interior on agricultural pesticides (carbofuran, chlordane, chlorpyrifos, diazinon, diflubenzuron, fenvalerate, mirex, paraquat, toxaphene), herbicides (acrolein, atrazine), metals and metalloids (arsenic, boron, cadmium, chromium, copper, lead, mercury, molybdenum, nickel, selenium, silver, tin, zinc), predacides (sodium monofluoroacetate), organic industrial wastes (dioxins, pentachlorophenol), veterinary chemicals (famphur), polycyclic aromatic hydrocarbons, polychlorinated biphenyls, mining wastes (cyanide), and ionizing radiations. This report is a cumulative index to the common and scientific names of all biological species listed in the first 34 reports in the CHR series, with individual species cross-referenced by contaminant and corresponding page numbers. A similar index is shown for chemicals.

  9. Predicting solvent-water partitioning of charged organic species using quantum-chemically estimated Abraham pp-LFER solute parameters.

    PubMed

    Davis, Craig Warren; Di Toro, Dominic M

    2016-12-01

    Methods for obtaining accurate predictions of solvent-water partitioning for neutral organic chemicals (e.g., Kow) are well-established. However, methods that provide comparable accuracy are not available for predicting the solvent-water partitioning of ionic species. Previous methods for addressing charge contributions to solvent-water partitioning rely on charged solute descriptors which are obtained from regressions to neutral species descriptors as well as charged descriptors which are specific to unique charge-functionalities and structural moieties. This paper presents a method for obtaining Abraham poly-parameter linear free energy relationship (pp-LFER) descriptors using quantum chemical calculations and molecular structure, only. The method utilizes a large number of solvent-water systems to overcome large errors in individual quantum chemical computations of ionic solvent-water partition coefficients. The result is a single set of quantum-chemically estimated Abraham solute parameters (QCAP) which are solvent-independent, and can be used to predict the solvent-water partitioning of ionic species. Predictions of solvent-water partition coefficients for ionic species using quantum-chemically estimated Abraham parameters (QCAPs) are shown to provide improved accuracy compared over both existing Absolv-estimated Abraham solute parameters (AAP) as well as direct a priori quantum chemical (QC) calculations for partitioning of anionic solutes in 4 organic solvent-water systems (RMS = 0.740, 2.48 and 0.426 for the Absolv, QC and QCAP methods, respectively). For quaternary amine cations in the octanol-water system the RMS errors of the solvent-water partition coefficients were larger and similar between the two Abraham models (RMSE = 0.997 and 1.16, for the AAP and QCAP methods, respectively). Both methods showed significant improvement over direct QC calculations (RMSE = 2.82). Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. RELATIVE BINDING AFFINITY OF ENDOCRINE DISRUPTING CHEMICALS TO ESTROGEN RECEPTOR IN TWO SPECIES OF FRESHWATER FISH

    EPA Science Inventory

    The US EPA has been mandated to screen industrial chemicals and pesticides for potential endocrine activity. To evaluate the potential for chemicals to cause endocrine disruption in fish we have previously measured the affinity of a number of chemicals for the rainbow trout estr...

  11. Chemical Evolution and Network Analysis in Protoplanetary Disks

    NASA Astrophysics Data System (ADS)

    Richard, D.; Davis, S. S.

    2005-12-01

    We present a study of the chemical evolution of protoplanetary disks focusing on the characteristics of the chemical network. Species of particular interest include H2O, CO, OCS, CH3OH and CH3OCH3. We simulate the evolution in a static bi-dimensional disk between the radii of 0.4 and 300 AU. The chemical network is built upon the UMIST rate database. The network is evolved until a stationary state is reached. Each species of interest's sub-network is analyzed to identify the most active reactions. In most cases, a small sub-set of reactions (2-5) is clearly dominant, accounting for more than 90% of the activity for a given species, at a given location. Because of the wide-ranging physical conditions in the disk, with temperatures from 10K to 2000K, these subsets of reactions vary with the location. For example, in the inner disk (0.4 AU), with temperatures over 2000K, H2O chemistry is dominated (in stationary state) by the reversible reaction H2 + OH ⇌ H2O + H ; at radius 0.7 AU, at a temperature of 950K, the activity is divided between H3O+ + HCN → HCNH+ + H2O and H3+ + H2O → H3O+ + H2 ; at 6 AU, with T=135K, between O- +H2 → H2O + e-; and H3+ + H2O → H3O+ + H2. There are two major benefits to identifying these reactions. The first is to reduce the number of chemical reactions to compute realistic abundances, and lower the cost of a future dynamical disk model coupled with the chemical evolution. The second benefit is to pick some reactions to be part of a current project to refine their rates using computational quantum chemistry techniques to address a major shortcoming: the lack of information or reliability concerning the temperature dependence of the reaction rates outside of the experimental window for which data was collected. A large number of rates form the UMIST database have no temperature dependence, and the ones that do are based on the classic Arrhenius law, which can be highly inaccurate if extrapolated over a large temperature range

  12. Chemical analysis of plasma-assisted antimicrobial treatment on cotton

    NASA Astrophysics Data System (ADS)

    Kan, C. W.; Lam, Y. L.; Yuen, C. W. M.; Luximon, A.; Lau, K. W.; Chen, K. S.

    2013-06-01

    This paper explores the use of plasma treatment as a pretreatment process to assist the application of antimicrobial process on cotton fabric with good functional effect. In this paper, antimicrobial finishing agent, Microfresh Liquid Formulation 9200-200 (MF), and a binder (polyurethane dispersion, Microban Liquid Formulation R10800-0, MB) will be used for treating the cotton fabric for improving the antimicrobial property and pre-treatment of cotton fabric by plasma under atmospheric pressure will be employed to improve loading of chemical agents. The chemical analysis of the treated cotton fabric will be conducted by Fourier transform Infrared Spectroscopy.

  13. Component pattern analysis of chemicals using multispectral THz imaging system

    NASA Astrophysics Data System (ADS)

    Kawase, Kodo; Ogawa, Yuichi; Watanabe, Yuki

    2004-04-01

    We have developed a novel basic technology for terahertz (THz) imaging, which allows detection and identification of chemicals by introducing the component spatial pattern analysis. The spatial distributions of the chemicals were obtained from terahertz multispectral transillumination images, using absorption spectra previously measured with a widely tunable THz-wave parametric oscillator. Further we have applied this technique to the detection and identification of illicit drugs concealed in envelopes. The samples we used were methamphetamine and MDMA, two of the most widely consumed illegal drugs in Japan, and aspirin as a reference.

  14. Near-field Optical Imagigng and Chemical Analysis

    NASA Astrophysics Data System (ADS)

    Andres, La Rosa

    1998-03-01

    Identification of molecular structures in complex mixtures represents a major challenge in chemical research today. Microfabricated devices or lab-on-a-chip that perform chemical analysis allows dynamic sampling of picoliter microenvironments and separation. The long-term goals of nanochemistry down to the femtoliter scale involve refinement of the detection limit to single-molecule. Our approach consists in designing a very sensitive near-field optical microscope (NSOM-SIAM) to explore the mesoscopic properties of organic compounds. The validity, sensitivity and unique spatial resolution of this system will be discussed for multiple analyte chemosensing.

  15. Technologies and microstructures for separation techniques in chemical analysis

    NASA Astrophysics Data System (ADS)

    Spiering, Vincent L.; Lammerink, Theo S. J.; Jansen, Henri V.; Fluitman, Jan H.; van den Berg, Albert

    1996-09-01

    The possibilities for microtechnology in chemical analysis and separation techniques are discussed. The combination of the materials and the dimensions of structures can limit the sample and waste volumes on the one hand, but also increases the performance of the chemical systems. Especially in high performance chromatography separation systems, where the separation quality is directly depending on the length to width ratio of the fluid channels, there is a large potential for applications. Novel technologies as well as demonstrator devices for different applications will be presented in this paper. Finally, a modular concept for microfluidic systems, in which these micromachined structures can be incorporated, is described and illustrated with a demonstrator.

  16. The Rules of Aggression: How Genetic, Chemical and Spatial Factors Affect Intercolony Fights in a Dominant Species, the Mediterranean Acrobat Ant Crematogaster scutellaris

    PubMed Central

    Frizzi, Filippo; Ciofi, Claudio; Dapporto, Leonardo; Natali, Chiara; Chelazzi, Guido; Turillazzi, Stefano; Santini, Giacomo

    2015-01-01

    Nest-mate recognition plays a key role in the biology of ants. Although individuals coming from a foreign nest are, in most cases, promptly rejected, the degree of aggressiveness towards non nest-mates may be highly variable among species and relies on genetic, chemical and environmental factors. We analyzed intraspecific relationships among neighboring colonies of the dominant Mediterranean acrobat ant Crematogaster scutellaris integrating genetic, chemical and behavioral analyses. Colony structure, parental relationships between nests, cuticular hydrocarbons profiles (CHCs) and aggressive behavior against non nest-mates were studied in 34 nests located in olive tree trunks. Bayesian clustering analysis of allelic variation at nine species-specific microsatellite DNA markers pooled nests into 14 distinct clusters, each representing a single colony, confirming a polydomous arrangement of nests in this species. A marked genetic separation among colonies was also detected, probably due to long distance dispersion of queens and males during nuptial flights. CHCs profiles varied significantly among colonies and between nests of the same colony. No relationship between CHCs profiles and genetic distances was detected. The level of aggressiveness between colonies was inversely related to chemical and spatial distance, suggesting a ‘nasty neighbor’ effect. Our findings also suggest that CHCs profiles in C. scutellaris may be linked to external environmental factors rather than genetic relationships. PMID:26445245

  17. The Rules of Aggression: How Genetic, Chemical and Spatial Factors Affect Intercolony Fights in a Dominant Species, the Mediterranean Acrobat Ant Crematogaster scutellaris.

    PubMed

    Frizzi, Filippo; Ciofi, Claudio; Dapporto, Leonardo; Natali, Chiara; Chelazzi, Guido; Turillazzi, Stefano; Santini, Giacomo

    2015-01-01

    Nest-mate recognition plays a key role in the biology of ants. Although individuals coming from a foreign nest are, in most cases, promptly rejected, the degree of aggressiveness towards non nest-mates may be highly variable among species and relies on genetic, chemical and environmental factors. We analyzed intraspecific relationships among neighboring colonies of the dominant Mediterranean acrobat ant Crematogaster scutellaris integrating genetic, chemical and behavioral analyses. Colony structure, parental relationships between nests, cuticular hydrocarbons profiles (CHCs) and aggressive behavior against non nest-mates were studied in 34 nests located in olive tree trunks. Bayesian clustering analysis of allelic variation at nine species-specific microsatellite DNA markers pooled nests into 14 distinct clusters, each representing a single colony, confirming a polydomous arrangement of nests in this species. A marked genetic separation among colonies was also detected, probably due to long distance dispersion of queens and males during nuptial flights. CHCs profiles varied significantly among colonies and between nests of the same colony. No relationship between CHCs profiles and genetic distances was detected. The level of aggressiveness between colonies was inversely related to chemical and spatial distance, suggesting a 'nasty neighbor' effect. Our findings also suggest that CHCs profiles in C. scutellaris may be linked to external environmental factors rather than genetic relationships.

  18. Differentiating salt marsh species using foreground/background analysis

    SciTech Connect

    Zhang, M.; Pinzon, J.; Ustin, S.L.; Rejmankova, E.

    1996-10-01

    Three California salt marsh plant species have distinctive morphologies that could be remotely sensed by airborne spectrometers because the architectures create differences in canopy reflectance characteristics. This paper presents a method to differentiate wetland species using a modified spectral mixture analysis termed hierarchical foreground and background analysis (HFBA). To validate this approach, the method was applied to field spectral data from several salt marshes. Foreground and background analysis allows the user to direct analysis along a specified axis of variance by identifying vectors through the n-dimensional spectral volume by identifying vectors that comprise the information of selected subset of spectra which emphasizes the presence of a discriminative signature of interest. The goal of FBA is to project spectral variation along the most relevant axis of variance that maximizes spectral differences between groups, while minimizing spectral variation within each group. For this work, we selected a training set that allowed us to create HFBA vectors which efficiently discriminate species based on canopy spectral characteristics. Results indicated that the dominant species in these salts marshes could be clearly differentiated with greater than 90% certainty from field collected canopy spectrometer data. Hundred percent of Spartina and 79% of Salicornia were correctly classified at the first level of classification. The accuracy of classification for Salicornia improved to 87% in the second level of classification. The unclassified spectral samples were related to extraordinary conditions within the wetlands such as extreme biomass, salinity and nitrogen conditions. These patterns were apparent in AVIRIS (Airborne Visible/infrared Imaging Spectrometer) images which showed distinct zonation corresponding to the distributions of these species in the marsh. Results were confirmed by field reconnaissance. 19 refs., 3 figs., 4 tabs.

  19. Natural background levels and threshold values of chemical species in three large-scale groundwater bodies in Northern Italy.

    PubMed

    Molinari, Antonio; Guadagnini, Laura; Marcaccio, Marco; Guadagnini, Alberto

    2012-05-15

    We analyze natural background levels (NBLs) and threshold values (TVs) of spatially distributed chemical species (NH(4), B and As) which may be a potential pressure and concern in three large scale alluvial and fluvio-deltaic aquifers at different depths of the Apennines and Po river plains in Emilia-Romagna, Northern Italy. Our results are based on statistical methodologies designed to separate the natural and anthropogenic contributions in monitored concentrations by modeling the empirical distribution of the detected concentration with a mixture of probability density functions. Available chemical observations are taken over a 20 years period and are associated with different depths and cover planar investigation scales of the order of hundreds of kilometers. High concentration values detected for NH(4) and B appear to be related to high natural background levels. Due to interaction with the host rock in different geochemical environments we observed that concentration vary in time and space (including in depth) consistently with the hydrogeochemical features and the occurrence of natural attenuation mechanisms in the analyzed reservoirs. Conversely, estimated As NBLs are not consistent with the conceptual model of the hydrogeochemical behavior of the systems analyzed and experimental evidences of As content in aquifer cores. This is due to the inability of these techniques to incorporate the complex dynamics of the processes associated with the specific hydrogeochemical setting. Statistical analyses performed upon aggregating the concentration data according to different time observation windows allow identifying temporal dynamics of NBLs and TVs of target compounds within the observation time frame. Our results highlight the benefit of a dynamic monitoring process and analysis of well demarcated groundwater bodies to update the associated NBLs as a function of the temporal dependence of natural processes occurring in the subsurface. Monitoring protocols could

  20. Chemical species of metallic elements in the aquatic environment of an ex-mining catchment.

    PubMed

    Ashraf, Muhammad Aqeel; Ahmad, Mushtaq; Akib, Shatirah; Balkhair, Khaled S; Abu Bakar, Nor Kartini

    2014-08-01

    This study was conducted to investigate the chemical speciation of dissolved and particulate elements (lead, zinc, copper, chromium, arsenic, and tin) in the mining wastewater of a former tin-mining catchment. The speciation patterns of dissolved elements were estimated by an adsorptive stripping voltammeter (ASV), while particulate elements were analyzed by using a newly developed sequential-extraction leaching procedure. The procedure has been operationally defined among five host fractions, namely exchangeable, carbonate, reducible, organic bound, and residual fractions. A total of six elements (lead, zinc, copper, chromium, arsenic, and tin) were analyzed in thirty samples at ten locations (P1-P10), with three samples taken from each of the ten locations, to get the average value from the former tin-mining catchment. The results showed that the heavy metal pollutions in locations P4 and P8 were more severe than in other sampling sites, especially tin and lead pollution. In the water samples from locations P4 and P8, both the total contents and the most dangerous non-residual fractions of tin and lead were extremely high. More than 90% of the total concentrations of arsenic and chromium existed in the residual fraction. Concentrations of copper and zinc mainly occurred in the residual fraction (more than 60%), while lead and tin presented mostly in the non-residual fractions in surface water. For all of the six dissolved elements, the less-labile species formed the predominant fraction in their speciation patterns. The speciation patterns of particulate elements showed that most of the concentrations of zinc, copper, chromium, and arsenic were found in the reducible fraction; whereas lead and tin were mainly associated with the organic fraction.

  1. Predicting co-morbidities in chemically sensitive individuals from exhaled breath analysis.

    PubMed

    Zeliger, Harold I; Pan, Yaqin; Rea, William J

    2012-09-01

    The exhaled breath of more than four hundred patients who presented at the Environmental Health Center - Dallas with chemical sensitivity conditions were analyzed for the relative abundance of their breath chemical composition by gas chromatography and mass spectrometry for volatile and semi-volatile organic compounds. All presenting patients had no fewer than four and as many as eight co-morbid conditions. Surprisingly, almost all the exhaled breath analyses showed the presence of a preponderance of lipophilic aliphatic and aromatic hydrocarbons. The hydrophilic compounds present were almost entirely of natural origin, i.e. expected metabolites of foods. The lipophile, primarily C3 to C16 hydrocarbons and believed to have come from inhalation of polluted air, were, in all cases, present at concentrations far below those known to be toxic to humans, but caused sensitivity and signs of chemical overload. The co-morbid health effects observed are believed to be caused by the sequential absorption of lipophilic and hydrophilic chemicals; an initial absorption and retention of lipophile followed by a subsequent absorption of hydrophilic species facilitated by the retained lipophile to produce chemical mixtures that are toxic at very low levels. It is hypothesized that co-morbid conditions in chemically sensitive individuals can be predicted from analysis of their exhaled breath.

  2. Genomic analysis of thermophilic Bacillus coagulans strains: efficient producers for platform bio-chemicals

    PubMed Central

    Su, Fei; Xu, Ping

    2014-01-01

    Microbial strains with high substrate efficiency and excellent environmental tolerance are urgently needed for the production of platform bio-chemicals. Bacillus coagulans has these merits; however, little genetic information is available about this species. Here, we determined the genome sequences of five B. coagulans strains, and used a comparative genomic approach to reconstruct the central carbon metabolism of this species to explain their fermentation features. A novel xylose isomerase in the xylose utilization pathway was identified in these strains. Based on a genome-wide positive selection scan, the selection pressure on amino acid metabolism may have played a significant role in the thermal adaptation. We also researched the immune systems of B. coagulans strains, which provide them with acquired resistance to phages and mobile genetic elements. Our genomic analysis provides comprehensive insights into the genetic characteristics of B. coagulans and paves the way for improving and extending the uses of this species. PMID:24473268

  3. Genomic analysis of thermophilic Bacillus coagulans strains: efficient producers for platform bio-chemicals.

    PubMed

    Su, Fei; Xu, Ping

    2014-01-29

    Microbial strains with high substrate efficiency and excellent environmental tolerance are urgently needed for the production of platform bio-chemicals. Bacillus coagulans has these merits; however, little genetic information is available about this species. Here, we determined the genome sequences of five B. coagulans strains, and used a comparative genomic approach to reconstruct the central carbon metabolism of this species to explain their fermentation features. A novel xylose isomerase in the xylose utilization pathway was identified in these strains. Based on a genome-wide positive selection scan, the selection pressure on amino acid metabolism may have played a significant role in the thermal adaptation. We also researched the immune systems of B. coagulans strains, which provide them with acquired resistance to phages and mobile genetic elements. Our genomic analysis provides comprehensive insights into the genetic characteristics of B. coagulans and paves the way for improving and extending the uses of this species.

  4. Biosynthesis, Chemical Structure, and Structure-Activity Relationship of Orfamide Lipopeptides Produced by Pseudomonas protegens and Related Species

    PubMed Central

    Ma, Zongwang; Geudens, Niels; Kieu, Nam P.; Sinnaeve, Davy; Ongena, Marc; Martins, José C.; Höfte, Monica

    2016-01-01

    Orfamide-type cyclic lipopeptides (CLPs) are biosurfactants produced by Pseudomonas and involved in lysis of oomycete zoospores, biocontrol of Rhizoctonia and insecticidal activity against aphids. In this study, we compared the biosynthesis, structural diversity, in vitro and in planta activities of orfamides produced by rhizosphere-derived Pseudomonas protegens and related Pseudomonas species. Genetic characterization together with chemical identification revealed that the main orfamide compound produced by the P. protegens group is orfamide A, while the related strains Pseudomonas sp. CMR5c and CMR12a produce orfamide B. Comparison of orfamide fingerprints led to the discovery of two new orfamide homologs (orfamide F and orfamide G) in Pseudomonas sp. CMR5c. The structures of these two CLPs were determined by nuclear magnetic resonance (NMR) and mass spectrometry (MS) analysis. Mutagenesis and complementation showed that orfamides determine the swarming motility of parental Pseudomonas sp. strain CMR5c and their production was regulated by luxR type regulators. Orfamide A and orfamide B differ only in the identity of a single amino acid, while orfamide B and orfamide G share the same amino acid sequence but differ in length of the fatty acid part. The biological activities of orfamide A, orfamide B, and orfamide G were compared in further bioassays. The three compounds were equally active against Magnaporthe oryzae on rice, against Rhizoctonia solani AG 4-HGI in in vitro assays, and caused zoospore lysis of Phytophthora and Pythium. Furthermore, we could show that orfamides decrease blast severity in rice plants by blocking appressorium formation in M. oryzae. Taken all together, our study shows that orfamides produced by P. protegens and related species have potential in biological control of a broad spectrum of fungal plant pathogens. PMID:27065956

  5. Computational analysis for velocity slip and diffusion species with carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Hayat, T.; Hussain, Zakir; Alsaedi, A.; Hobiny, A.

    This article addresses a computational study for carbon nanotubes with diffusion species. Mathematical analysis and modeling are formulated in the presence of slip effect, Darcy porous medium and chemical species. Diffusion coefficients are accounted as equal amount. Optimal Homotopy Analysis Method (OHAM) is implemented in taking care for convergence control parameters. Residual errors and its graphs are plotted for CNTs nanofluids. The current data is compared with the previous published work. The results are found in favorable agreement. Physically interesting parameters are highlighted. The velocity is dominated for MWCNT than SWCNT. The velocity profile increases for power index when m > 1 while opposite trend is observed for power index when m < 1 . Permeability parameter and volume fraction reduce the skin friction coefficient and reverse trend is noticed for slip parameter and wall thickness parameter. Opposite behavior is noticed for concentration profile at surface for homogenous-heterogeneous reactions parameters.

  6. SPECIES-ABUNDANCE-BIOMASS RESPONSES BY ESTUARINE MACROBENTHOS TO SEDIMENT CHEMICAL CONTAMINATION.

    EPA Science Inventory

    Macrobenthic community responses can be measured through concerted changes in univariate metrics, including species richness, total abundance, and total biomass. The classic model of pollution effects on marine macroinvertebrate communities recognizes that species/abundance/bioma...

  7. SPECIES-ABUNDANCE-BIOMASS RESPONSES BY ESTUARINE MACROBENTHOS TO SEDIMENT CHEMICAL CONTAMINATION.

    EPA Science Inventory

    Macrobenthic community responses can be measured through concerted changes in univariate metrics, including species richness, total abundance, and total biomass. The classic model of pollution effects on marine macroinvertebrate communities recognizes that species/abundance/bioma...

  8. Chemical Species in the Vapor Phase of Hanford Double-Shell Tanks: Potential Impacts on Waste Tank Corrosion Processes

    SciTech Connect

    Felmy, Andrew R.; Qafoku, Odeta; Arey, Bruce W.; Boomer, Kayle D.

    2010-09-22

    The presence of corrosive and inhibiting chemicals on the tank walls in the vapor space, arising from the waste supernatant, dictate the type and degree of corrosion that occurs there. An understanding of how waste chemicals are transported to the walls and the affect on vapor species from changing supernatant chemistry (e.g., pH, etc.), are basic to the evaluation of risks and impacts of waste changes on vapor space corrosion (VSC). In order to address these issues the expert panel workshop on double-shell tank (DST) vapor space corrosion testing (RPP-RPT-31129) participants made several recommendations on the future data and modeling needs in the area of DST corrosion. In particular, the drying of vapor phase condensates or supernatants can form salt or other deposits at the carbon steel interface resulting in a chemical composition at the near surface substantially different from that observed directly in the condensates or the supernatants. As a result, over the past three years chemical modeling and experimental studies have been performed on DST supernatants and condensates to predict the changes in chemical composition that might occur as condensates or supernatants equilibrate with the vapor space species and dry at the carbon steel surface. The experimental studies included research on both the chemical changes that occurred as the supernatants dried as well as research on how these chemical changes impact the corrosion of tank steels. The chemical modeling and associated experimental studies were performed at the Pacific Northwest National Laboratory (PNNL) and the research on tank steel corrosion at the Savannah River National Laboratory (SRNL). This report presents a summary of the research conducted at PNNL with special emphasis on the most recent studies conducted in FY10. An overall summary of the project results as well as their broader implications for vapor space corrosion of the DST’s is given at the end of this report.

  9. Comparative Analysis of Genome Sequences Covering the Seven Cronobacter Species

    PubMed Central

    Cummings, Craig A.; Shih, Rita; Degoricija, Lovorka; Rico, Alain; Brzoska, Pius; Hamby, Stephen E.; Masood, Naqash; Hariri, Sumyya; Sonbol, Hana; Chuzhanova, Nadia; McClelland, Michael; Furtado, Manohar R.; Forsythe, Stephen J.

    2012-01-01

    Background Species of Cronobacter are widespread in the environment and are occasional food-borne pathogens associated with serious neonatal diseases, including bacteraemia, meningitis, and necrotising enterocolitis. The genus is composed of seven species: C. sakazakii, C. malonaticus, C. turicensis, C. dublinensis, C. muytjensii, C. universalis, and C. condimenti. Clinical cases are associated with three species, C. malonaticus, C. turicensis and, in particular, with C. sakazakii multilocus sequence type 4. Thus, it is plausible that virulence determinants have evolved in certain lineages. Methodology/Principal Findings We generated high quality sequence drafts for eleven Cronobacter genomes representing the seven Cronobacter species, including an ST4 strain of C. sakazakii. Comparative analysis of these genomes together with the two publicly available genomes revealed Cronobacter has over 6,000 genes in one or more strains and over 2,000 genes shared by all Cronobacter. Considerable variation in the presence of traits such as type six secretion systems, metal resistance (tellurite, copper and silver), and adhesins were found. C. sakazakii is unique in the Cronobacter genus in encoding genes enabling the utilization of exogenous sialic acid which may have clinical significance. The C. sakazakii ST4 strain 701 contained additional genes as compared to other C. sakazakii but none of them were known specific virulence-related genes. Conclusions/Significance Genome comparison revealed that pair-wise DNA sequence identity varies between 89 and 97% in the seven Cronobacter species, and also suggested various degrees of divergence. Sets of universal core genes and accessory genes unique to each strain were identified. These gene sequences can be used for designing genus/species specific detection assays. Genes encoding adhesins, T6SS, and metal resistance genes as well as prophages are found in only subsets of genomes and have contributed considerably to the variation of

  10. Demonstration of fast and accurate discrimination and quantification of chemically similar species utilizing a single cross-selective chemiresistor.

    PubMed

    Vergara, Alexander; Benkstein, Kurt D; Montgomery, Christopher B; Semancik, Steve

    2014-07-15

    Performance characteristics of gas-phase microsensors will determine the ultimate utility of these devices for a wide range of chemical monitoring applications. Commonly employed chemiresistor elements are quite sensitive to selected analytes, and relatively new methods have increased the selectivity to specific compounds, even in the presence of interfering species. Here, we have focused on determining whether purposefully driven temperature modulation can produce faster sensor-response characteristics, which could enable measurements for a broader range of applications involving dynamic compositional analysis. We investigated the response speed of a single chemiresitive In2O3 microhotplate sensor to four analytes (methanol, ethanol, acetone, 2-butanone) by systematically varying the oscillating frequency (semicycle periods of 20-120 ms) of a bilevel temperature cycle applied to the sensing element. It was determined that the fastest response (≈ 9 s), as indicated by a 98% signal-change metric, occurred for a period of 30 ms and that responses under such modulation were dramatically faster than for isothermal operation of the same device (>300 s). Rapid modulation between 150 and 450 °C exerts kinetic control over transient processes, including adsorption, desorption, diffusion, and reaction phenomena, which are important for charge transfer occurring in transduction processes and the observed response times. We also demonstrate that the fastest operation is accompanied by excellent discrimination within a challenging 16-category recognition problem (consisting of the four analytes at four separate concentrations). This critical finding demonstrates that both speed and high discriminatory capabilities can be realized through temperature modulation.

  11. Spectrofluorometric determination and chemical speciation of trace concentrations of tungsten species in water using the ion pairing reagent procaine hydrochloride.

    PubMed

    El-Shahawi, M S; Al Khateeb, L A

    2012-01-15

    A highly selective and low cost extractive spectrofluorimetric method was developed for determination of trace concentrations of tungsten (VI) in water. The method was based upon solvent extraction of the developed ion associate [(PQH(+))(2)·WO(4)(2-)] of the fluorescent ion-pairing reagent [2-(diethylamino)ethyl 4 aminobenzoate] hydrochloride namely procaine hydrochloride, PQH(+)·Cl(-) and tungstate (WO(4)(2-)) in aqueous solution of pH 6-7 followed by measuring the resulting fluorescence enhancement in n-hexane at λ(ex/em)=270/320nm. The fluorescence intensity of PQH(+)·Cl(-) increased linearly on increasing tungstate concentration in the range 25-250μgL(-1). The limits of detection (LOD) and quantification (LOQ) of tungsten (VI) were found 7.51 and 24.75μgL(-1), respectively. Chemical composition of the developed ion associate and the molar absorptivity at 270nm were found to be [(PQH(+))(2)·WO(4)(2-)] and 2.7×10(4)Lmol(-1)cm(-1), respectively. Other oxidation states (III, IV, V) of tungsten species could also be determined after oxidation with H(2)O(2) in aqueous solution to tungsten (VI). The method was applied for analysis of tungsten in certified reference material (IAEA Soil-7) and wastewater samples. The results were compared successfully (>95%) with the data of inductively coupled plasma-mass spectrometry (ICP-MS).

  12. The Effect of Chemical Treatments on Lampenflora and a Collembola Indicator Species at a Popular Tour Cave in California, USA

    NASA Astrophysics Data System (ADS)

    Meyer, Erik; Seale, L. Don; Permar, Brianne; McClary, Andrew

    2017-06-01

    Growth of invasive, opportunistic plants (i.e. lampenflora) in popular tour caves is a significant concern for land managers worldwide. Numerous chemicals at various concentrations have been utilized to remove phototrophic lampenflora colonizing artificially lit surfaces within these caves; however formulations, effectiveness, and impacts appear anecdotal and temporally limited. At Crystal Cave, Sequoia National Park, California, we study lampenflora and cave springtail ( Tomocerus celsus) response to a single 0.05 ml/cm2 dose of 1.0% sodium hypochlorite, 0.5% sodium hypochlorite, and 15.0% hydrogen peroxide compared to no treatment over the course of one year. Additionally, we explore potential food web impacts resulting from invasive lampenflora in naturally oligotrophic caves by utilizing stable isotope analysis of T. celsus found on and off lampenflora. Time-effect decay models indicate 1.0 and 0.5% sodium hypochlorite effectively eliminate lampenflora in 11 and 21 days, respectively, while lampenflora decay projections exceed 600 days with 15.0% hydrogen peroxide treatment. Repeat surveys of T. celsus indicate a negative response to 1.0% sodium hypochlorite ( P = 0.02), and the probability of observing T. celsus was inversely related to the effectiveness of each treatment. Further, T. celsus had similar diets regardless of their lampenflora association ( P = 0.92). We conclude that treatments of sodium hypochlorite at or below 0.5% achieve management goals with limited impacts to the presence or diet of a common cave-adapted indicator species.

  13. Chemical Composition and Insecticidal Activity of Essential Oils from Zanthoxylum dissitum Leaves and Roots against Three Species of Storage Pests.

    PubMed

    Wang, Cheng-Fang; Yang, Kai; You, Chun-Xue; Zhang, Wen-Juan; Guo, Shan-Shan; Geng, Zhu-Feng; Du, Shu-Shan; Wang, Yong-Yan

    2015-05-04

    This work aimed to investigate chemical composition of essential oils obtained from Zanthoxylum dissitum leaves and roots and their insecticidal activities against several stored product pests, namely the cigarette beetle (Lasioderma serricorne), red flour beetle (Tribolium castaneum) and black carpet beetle (Attagenus piceus). The analysis by GC-MS of the essential oils allowed the identification of 28 and 22 components, respectively. It was found that sesquiterpenoids comprised a fairly high portion of the two essential oils, with percentages of 74.0% and 80.9% in the leaves and roots, respectively. The main constituents identified in the essential oil of Z. dissitum leaves were δ-cadinol (12.8%), caryophyllene (12.7%), β-cubebene (7.9%), 4-terpineol (7.5%) and germacrene D-4-ol (5.7%), while humulene epoxide II (29.4%), caryophyllene oxide (24.0%), diepicedrene-1-oxide (10.7%) and Z,Z,Z-1,5,9,9-tetramethyl-1,4,7-cycloundecatriene (8.7%) were the major components in the essential oil of Z. dissitum roots. The insecticidal activity results indicated that the essential oil of Z. dissitum roots exhibited moderate contact toxicity against three species of storage pests, L. serricorne,T. castaneum and A. piceus, with LD50 values of 13.8, 43.7 and 96.8 µg/adult, respectively.

  14. Gene expression responses of HeLa cells to chemical species generated by an atmospheric plasma flow

    SciTech Connect

    Yokoyama, Mayo; Johkura, Kohei; Sato, Takehiko

    2014-08-08

    Highlights: • Response of HeLa cells to a plasma-irradiated medium was revealed by DNA microarray. • Gene expression pattern was basically different from that in a H{sub 2}O{sub 2}-added medium. • Prominently up-/down-regulated genes were partly shared by the two media. • Gene ontology analysis showed both similar and different responses in the two media. • Candidate genes involved in response to ROS were detected in each medium. - Abstract: Plasma irradiation generates many factors able to affect the cellular condition, and this feature has been studied for its application in the field of medicine. We previously reported that hydrogen peroxide (H{sub 2}O{sub 2}) was the major cause of HeLa cell death among the chemical species generated by high level irradiation of a culture medium by atmospheric plasma. To assess the effect of plasma-induced factors on the response of live cells, HeLa cells were exposed to a medium irradiated by a non-lethal plasma flow level, and their gene expression was broadly analyzed by DNA microarray in comparison with that in a corresponding concentration of 51 μM H{sub 2}O{sub 2}. As a result, though the cell viability was sufficiently maintained at more than 90% in both cases, the plasma-medium had a greater impact on it than the H{sub 2}O{sub 2}-medium. Hierarchical clustering analysis revealed fundamentally different cellular responses between these two media. A larger population of genes was upregulated in the plasma-medium, whereas genes were downregulated in the H{sub 2}O{sub 2}-medium. However, a part of the genes that showed prominent differential expression was shared by them, including an immediate early gene ID2. In gene ontology analysis of upregulated genes, the plasma-medium showed more diverse ontologies than the H{sub 2}O{sub 2}-medium, whereas ontologies such as “response to stimulus” were common, and several genes corresponded to “response to reactive oxygen species.” Genes of AP-1 proteins, e.g., JUN

  15. Chemical contamination assessment in mangrove-lined Caribbean coastal systems using the oyster Crassostrea rhizophorae as biomonitor species.

    PubMed

    Aguirre-Rubí, Javier R; Luna-Acosta, Andrea; Etxebarría, Nestor; Soto, Manu; Espinoza, Félix; Ahrens, Michael J; Marigómez, Ionan

    2017-05-24

    This paper aims to contribute to the use of mangrove cupped oyster, Crassostrea rhizophorae, as a biomonitor species for chemical contamination assessment in mangrove-lined Caribbean coastal systems. Sampling was carried out in eight localities (three in Nicaragua and five in Colombia) with different types and levels of contamination. Oysters were collected during the rainy and dry seasons of 2012-2013 and the tissue concentrations of metals, polycyclic aromatic hydrocarbons (PAHs), and persistent organic pollutants (POPs) were determined. Low tissue concentrations of metals (except Hg) and PAHs; moderate-to-high tissue concentrations of Hg, hexachlorocyclohexanes (HCHs), and dichlorodiphenyl-trichloroethanes (DDTs); detectable levels of chlorpyrifos, polychlorinated biphenyls (PCBs) (mainly CB28, CB118, CB138 and CB 153) and brominated diphenyl ethers 85 (BDE85); and negligible levels of musks were recorded in Nicaraguan oysters. A distinct profile of POPs was identified in Colombia, where the tissue concentrations of PCBs and synthetic musk fragrances were low to moderate, and Ag, As, Cd, Pb, and PAHs ranged from moderate to extremely high. Overall, the values recorded for HCHs, DDTs and PCBs in Nicaraguan mangrove cupped oysters greatly exceeded the reference values in tissues of C. rhizophorae from the Wider Caribbean Region, whereas only the levels of PCBs were occasionally surpassed in Colombia. Different contaminant profiles were distinguished between oysters from Nicaragua and Colombia in radar plots constructed using the main groups of contaminants (metals, PAHs, musks, PCBs, and organochlorine pesticides (OCPs)). Likewise, integrated pollution indices revealed differences in the levels of contaminants. Moreover, the profiles and levels in oyster tissues also varied with season. Thus, principal component analysis clearly discriminated Nicaraguan and Colombian localities and, especially in Colombia, seasonal trends in chemical contamination and differences

  16. Chemically reactive species in liquids generated by atmospheric-pressure plasmas and their roles in plasma medicine

    NASA Astrophysics Data System (ADS)

    Hamaguchi, Satoshi

    2013-07-01

    Plasmas whose gas temperatures are close to room temperature may be generated in ambient air or a gas at atmospheric pressure with the use of low-frequency high voltage or low-power radio-frequency (RF) or microwave power applied to electrodes. Such plasmas can serve as a powerful source of free radicals and/or chemically reactive species that arise from atoms and molecules of the ambient gas. Recently use of such plasmas for medical purposes has attracted much attention as they can be implemented in possible medical devices that can cause blood coagulation, heal wounds, facilitate angiogenesis, sterilize surgical devices as well as living tissues without harming healthy cells, and selectively inactivate cancer cells. Especially of interest among reactive species generated by atmospheric-pressure plasmas (APP) are reactive oxygen species (ROS) and reactive nitrogen species (RNS) that are generated in liquid phase. Since most living tissues and cells are immersed in liquids (such as blood or culture media), reactive species generated by APPs in the gas phase are transported to the liquid phase and possibly converted to different types of reactive species therein before causing some influence on the tissues or cells. In this study, the rate equations are solved to evaluate concentrations of various reactive species in pure water that are originated by plasma reactions in atmosphere and possible effects of such species (including ROS/RNS) on living tissues and cells are discussed.

  17. Chemically reactive species in liquids generated by atmospheric-pressure plasmas and their roles in plasma medicine

    SciTech Connect

    Hamaguchi, Satoshi

    2013-07-11

    Plasmas whose gas temperatures are close to room temperature may be generated in ambient air or a gas at atmospheric pressure with the use of low-frequency high voltage or low-power radio-frequency (RF) or microwave power applied to electrodes. Such plasmas can serve as a powerful source of free radicals and/or chemically reactive species that arise from atoms and molecules of the ambient gas. Recently use of such plasmas for medical purposes has attracted much attention as they can be implemented in possible medical devices that can cause blood coagulation, heal wounds, facilitate angiogenesis, sterilize surgical devices as well as living tissues without harming healthy cells, and selectively inactivate cancer cells. Especially of interest among reactive species generated by atmospheric-pressure plasmas (APP) are reactive oxygen species (ROS) and reactive nitrogen species (RNS) that are generated in liquid phase. Since most living tissues and cells are immersed in liquids (such as blood or culture media), reactive species generated by APPs in the gas phase are transported to the liquid phase and possibly converted to different types of reactive species therein before causing some influence on the tissues or cells. In this study, the rate equations are solved to evaluate concentrations of various reactive species in pure water that are originated by plasma reactions in atmosphere and possible effects of such species (including ROS/RNS) on living tissues and cells are discussed.

  18. Hierarchical analysis of species distributions and abundance across environmental gradients.

    PubMed

    Diez, Jeffrey M; Pulliam, H Ronald

    2007-12-01

    Abiotic and biotic processes operate at multiple spatial and temporal scales to shape many ecological processes, including species distributions and demography. Current debate about the relative roles of niche-based and stochastic processes in shaping species distributions and community composition reflects, in part, the challenge of understanding how these processes interact across scales. Traditional statistical models that ignore autocorrelation and spatial hierarchies can result in misidentification of important ecological covariates. Here, we demonstrate the utility of a hierarchical modeling framework for testing hypotheses about the importance of abiotic factors at different spatial scales and local spatial autocorrelation for shaping species distributions and abundances. For the two orchid species studied, understory light availability and soil moisture helped to explain patterns of presence and abundance at a microsite scale (<4 m2), while soil organic content was important at a population scale (<400 m2). The inclusion of spatial autocorrelation is shown to alter the magnitude and certainty of estimated relationships between abundance and abiotic variables, and we suggest that such analysis be used more often to explore the relationships between species life histories and distributions. The hierarchical modeling framework is shown to have great potential for elucidating ecological relationships involving abiotic and biotic processes simultaneously at multiple scales.

  19. Comparative analysis of ADS gene promoter in seven Artemisia species.

    PubMed

    Ranjbar, Mojtaba; Naghavi, Mohammad Reza; Alizadeh, Hoshang

    2014-12-01

    Artemisinin is the most effective antimalarial drug that is derived from Artemisia annua. Amorpha-4,11-diene synthase (ADS) controls the first committed step in artemisinin biosynthesis. The ADS gene expression is regulated by transcription factors which bind to the cis-acting elements on the ADS promoter and are probably responsible for the ADS gene expression difference in the Artemisia species. To identify the elements that are significantly involved in ADS gene expression, the ADS gene promoter of the seven Artemisia species was isolated and comparative analysis was performed on the ADS promoter sequences of these species. Results revealed that some of the cis-elements were unique or in terms of number were more in the high artemisinin producer species, A. annua, than the other species. We have reported that the light-responsive elements, W-box, CAAT-box, 5'-UTR py-rich stretch, TATA-box sequence and tandem repeat sequences have been identified as important factors in the increased expression of ADS gene.

  20. Assessing Contaminant Sensitivity of Endangered and Threatened Aquatic Species: Part I. Acute Toxicity of Five Chemicals

    EPA Science Inventory

    Early life-stage toxicity tests with copper and pentachlorophenol (PCP) were conducted with two species listed under the U.S. Endangered Species Act (fountain darter, Etheostoma fonticola, and spotfin chub, Cyprinella monacha) and two surrogate species (fathead minnow, Pimephales...

  1. Assessing Contaminant Sensitivity of Endangered and Threatened Aquatic Species: Part I. Acute Toxicity of Five Chemicals

    EPA Science Inventory

    Early life-stage toxicity tests with copper and pentachlorophenol (PCP) were conducted with two species listed under the U.S. Endangered Species Act (fountain darter, Etheostoma fonticola, and spotfin chub, Cyprinella monacha) and two surrogate species (fathead minnow, Pimephales...

  2. Mycobacterial species as case-study of comparative genome analysis.

    PubMed

    Zakham, F; Belayachi, L; Ussery, D; Akrim, M; Benjouad, A; El Aouad, R; Ennaji, M M

    2011-02-08

    The genus Mycobacterium represents more than 120 species including important pathogens of human and cause major public health problems and illnesses. Further, with more than 100 genome sequences from this genus, comparative genome analysis can provide new insights for better understanding the evolutionary events of these species and improving drugs, vaccines, and diagnostics tools for controlling Mycobacterial diseases. In this present study we aim to outline a comparative genome analysis of fourteen Mycobacterial genomes: M. avium subsp. paratuberculosis K—10, M. bovis AF2122/97, M. bovis BCG str. Pasteur 1173P2, M. leprae Br4923, M. marinum M, M. sp. KMS, M. sp. MCS, M. tuberculosis CDC1551, M. tuberculosis F11, M. tuberculosis H37Ra, M. tuberculosis H37Rv, M. tuberculosis KZN 1435 , M. ulcerans Agy99,and M. vanbaalenii PYR—1, For this purpose a comparison has been done based on their length of genomes, GC content, number of genes in different data bases (Genbank, Refseq, and Prodigal). The BLAST matrix of these genomes has been figured to give a lot of information about the similarity between species in a simple scheme. As a result of multiple genome analysis, the pan and core genome have been defined for twelve Mycobacterial species. We have also introduced the genome atlas of the reference strain M. tuberculosis H37Rv which can give a good overview of this genome. And for examining the phylogenetic relationships among these bacteria, a phylogenic tree has been constructed from 16S rRNA gene for tuberculosis and non tuberculosis Mycobacteria to understand the evolutionary events of these species.

  3. Toxic hazard and chemical analysis of leachates from furfurylated wood.

    PubMed

    Pilgård, Annica; Treu, Andreas; van Zeeland, Albert N T; Gosselink, Richard J A; Westin, Mats

    2010-09-01

    The furfurylation process is an extensively investigated wood modification process. Furfuryl alcohol molecules penetrate into the wood cell wall and polymerize in situ. This results in a permanent swelling of the wood cell walls. It is unclear whether or not chemical bonds exist between the furfuryl alcohol polymer and the wood. In the present study, five different wood species were used, both hardwoods and softwoods. They were treated with three different furfurylation procedures and leached according to three different leaching methods. The present study shows that, in general, the leachates from furfurylated wood have low toxicity. It also shows that the choice of leaching method is decisive for the outcome of the toxicity results. Earlier studies have shown that leachates from wood treated with furfuryl alcohol prepolymers have higher toxicity to Vibrio fischeri than leachates from wood treated with furfuryl alcohol monomers. This is probably attributable to differences in leaching of chemical compounds. The present study shows that this difference in the toxicity most likely cannot be attributed to maleic acid, furan, furfural, furfuryl alcohol, or 2-furoic acid. However, the difference might be caused by the two substances 5-hydroxymethylfurfural and 2,5-furandimethanol. The present study found no difference in the amount of leached furfuryl alcohol between leachates from furfurylated softwood and furfurylated hardwood species. Earlier studies have indicated differences in grafting of furfuryl alcohol to lignin. However, nothing was found in the present study that could support this. The leachates of furfurylated wood still need to be

  4. Morphometric Analysis of Anguina amsinckiae from Three Host Species

    PubMed Central

    Pantone, Dan James; Griesbach, John A.; Maggenti, A. R.

    1987-01-01

    Amsinckia species (fiddleneck) in the South Coast Ranges of California were surveyed to determine if any of the 12 different California species of Amsinckia are hosts of the nematode, Anguina amsinckiae (Steiner and Scott, 1935) Thorne, 1961. Previously only Amsinckia intermedia Fischer and Meyer was reported as a host of Anguina amsinckiae. The survey established that there are at least two additional hosts of Anguina amsinckiae: Amsinckia lycopsoides Lehmann and Amsinckia gloriosa Suksdorf. Seven sites containing nematode-infected Amsinckia plants were discovered. Every site contained two or more species of Amsinckia; however, only one site contained more than one species of Amsinckia that was galled. Nematode specimens from A. intermedia, A. lycopsoides, and A. gloriosa were used in a morphometric analysis of 14 morphological variables. Stepwise discriminant analysis of the variables to separate the populations by host were successful for females, and the pairwise F-tests showed all three populations to have different group means (P < 0.05). Males from the three hosts were not always separable, however, as only the nematodes from Amsinckia gloriosa had a different group mean (P < 0.05). PMID:19290124

  5. Morphometric Analysis of Anguina amsinckiae from Three Host Species.

    PubMed

    Pantone, D J; Griesbach, J A; Maggenti, A R

    1987-04-01

    Amsinckia species (fiddleneck) in the South Coast Ranges of California were surveyed to determine if any of the 12 different California species of Amsinckia are hosts of the nematode, Anguina amsinckiae (Steiner and Scott, 1935) Thorne, 1961. Previously only Amsinckia intermedia Fischer and Meyer was reported as a host of Anguina amsinckiae. The survey established that there are at least two additional hosts of Anguina amsinckiae: Amsinckia lycopsoides Lehmann and Amsinckia gloriosa Suksdorf. Seven sites containing nematode-infected Amsinckia plants were discovered. Every site contained two or more species of Amsinckia; however, only one site contained more than one species of Amsinckia that was galled. Nematode specimens from A. intermedia, A. lycopsoides, and A. gloriosa were used in a morphometric analysis of 14 morphological variables. Stepwise discriminant analysis of the variables to separate the populations by host were successful for females, and the pairwise F-tests showed all three populations to have different group means (P < 0.05). Males from the three hosts were not always separable, however, as only the nematodes from Amsinckia gloriosa had a different group mean (P < 0.05).

  6. Correlation Spectroscopy of Minor Species: Signal Purification and Distribution Analysis

    SciTech Connect

    Laurence, T A; Kwon, Y; Yin, E; Hollars, C; Camarero, J A; Barsky, D

    2006-06-21

    We are performing experiments that use fluorescence resonance energy transfer (FRET) and fluorescence correlation spectroscopy (FCS) to monitor the movement of an individual donor-labeled sliding clamp protein molecule along acceptor-labeled DNA. In addition to the FRET signal sought from the sliding clamp-DNA complexes, the detection channel for FRET contains undesirable signal from free sliding clamp and free DNA. When multiple fluorescent species contribute to a correlation signal, it is difficult or impossible to distinguish between contributions from individual species. As a remedy, we introduce ''purified FCS'' (PFCS), which uses single molecule burst analysis to select a species of interest and extract the correlation signal for further analysis. We show that by expanding the correlation region around a burst, the correlated signal is retained and the functional forms of FCS fitting equations remain valid. We demonstrate the use of PFCS in experiments with DNA sliding clamps. We also introduce ''single molecule FCS'', which obtains diffusion time estimates for each burst using expanded correlation regions. By monitoring the detachment of weakly-bound 30-mer DNA oligomers from a single-stranded DNA plasmid, we show that single molecule FCS can distinguish between bursts from species that differ by a factor of 5 in diffusion constant.

  7. Effects of species and season on chemical composition and ruminal crude protein and organic matter degradability of some multi-purpose tree species by West African dwarf rams.

    PubMed

    Arigbede, O M; Anele, U Y; Südekum, K-H; Hummel, J; Oni, A O; Olanite, J A; Isah, A O

    2012-04-01

    Seasonal chemical composition and ruminal organic matter (OM) and crude protein (CP) degradabilities were determined in four tropical multi-purpose tree species (MPTS) namely; Pterocarpus santalinoides, Grewia pubescens, Enterolobium cyclocarpum and Leucaena leucocephala. Three West African dwarf (WAD) rams fitted with permanent rumen cannula were used for the degradability trials. Foliage samples were collected four times to represent seasonal variations as follows: January--mid dry; April--late dry; July--mid rainy and October--late rainy seasons. Leaf samples were randomly collected from the trees for estimation of dry matter (DM) and chemical composition. Ruminal in sacco OM and CP degradabilities were estimated from residues in nylon bags. All samples had high CP (161-259 g/kg DM) and moderate fibre concentrations [neutral detergent fibre (without residual ash], 300-501 g/kg DM; acid detergent fibre (without residual ash), 225-409 g/kg DM and acid detergent lignin, 87-179 g/kg DM across seasons. Interaction effects of species and season on chemical composition were highly significant (p = 0.001) except for trypsin inhibitor (p = 0.614). The MPTS recorded more than 60% OM and CP degradability at 24 h, which implied that they were all highly degradable in the rumen. Their incorporation into ruminant feeding systems as dry season forage supplements is therefore recommended.

  8. Automating the analytical laboratory via the Chemical Analysis Automation paradigm

    SciTech Connect

    Hollen, R.; Rzeszutko, C.

    1997-10-01

    To address the need for standardization within the analytical chemistry laboratories of the nation, the Chemical Analysis Automation (CAA) program within the US Department of Energy, Office of Science and Technology`s Robotic Technology Development Program is developing laboratory sample analysis systems that will automate the environmental chemical laboratories. The current laboratory automation paradigm consists of islands-of-automation that do not integrate into a system architecture. Thus, today the chemist must perform most aspects of environmental analysis manually using instrumentation that generally cannot communicate with other devices in the laboratory. CAA is working towards a standardized and modular approach to laboratory automation based upon the Standard Analysis Method (SAM) architecture. Each SAM system automates a complete chemical method. The building block of a SAM is known as the Standard Laboratory Module (SLM). The SLM, either hardware or software, automates a subprotocol of an analysis method and can operate as a standalone or as a unit within a SAM. The CAA concept allows the chemist to easily assemble an automated analysis system, from sample extraction through data interpretation, using standardized SLMs without the worry of hardware or software incompatibility or the necessity of generating complicated control programs. A Task Sequence Controller (TSC) software program schedules and monitors the individual tasks to be performed by each SLM configured within a SAM. The chemist interfaces with the operation of the TSC through the Human Computer Interface (HCI), a logical, icon-driven graphical user interface. The CAA paradigm has successfully been applied in automating EPA SW-846 Methods 3541/3620/8081 for the analysis of PCBs in a soil matrix utilizing commercially available equipment in tandem with SLMs constructed by CAA.

  9. Root-inhabiting fungi in alien plant species in relation to invasion status and soil chemical properties.

    PubMed

    Majewska, Marta L; Błaszkowski, Janusz; Nobis, Marcin; Rola, Kaja; Nobis, Agnieszka; Łakomiec, Daria; Czachura, Paweł; Zubek, Szymon

    In order to recognize interactions between alien vascular plants and soil microorganisms and thus better understand the mechanisms of plant invasions, we examined the mycorrhizal status, arbuscular mycorrhizal fungi (AMF) colonization rate, arbuscular mycorrhiza (AM) morphology and presence of fungal root endophytes in 37 non-native species in Central Europe. We also studied the AMF diversity and chemical properties of soils from under these species. The plant and soil materials were collected in southern Poland. We found that 35 of the species formed AM and their mycorrhizal status depended on species identity. Thirty-three taxa had AM of Arum-type alone. Lycopersicon esculentum showed intermediate AM morphology and Eragrostis albensis developed both Arum and Paris. The mycelia of dark septate endophytes (DSE) were observed in 32 of the species, while sporangia of Olpidium spp. were found in the roots of 10. Thirteen common and worldwide occurring AMF species as well as three unidentified spore morphotypes were isolated from trap cultures established with the soils from under the plant species. Claroideoglomus claroideum, Funneliformis mosseae and Septoglomus constrictum were found the most frequently. The presence of root-inhabiting fungi and the intensity of their colonization were not correlated with soil chemical properties, plant invasion status, their local abundance and habitat type. No relationships were also found between the presence of AMF, DSE and Olpidium spp. These suggest that other edaphic conditions, plant and fungal species identity or the abundance of these fungi in soils might have an impact on the occurrence and intensity of fungal root colonization in the plants under study.

  10. A pocket-sized solid-state optical waveguide chemical sensor for in-field monitoring of toxic species

    SciTech Connect

    Pollina, R.J.; Klainer, S.M.; Saini, D.; Diaz, D.

    1997-12-31

    We are introducing a prototype design of a working model for a pocket-sized, rugged, low-cost personal dosimeter or point detector which utilizes an optical waveguide chemical sensor that we have recently developed. We believe that this prototype, made possible by the use of the hybrid integrated circuit chip, is a giant leap forward in the technology of point dosimeters. With the appropriate communications and power source, the output can be fed into building monitoring grids, emergency response databases, and even Internet-based national or international monitoring grids. The device is suitable for detecting toxic species, industrial chemicals, drugs, and explosives.

  11. Exploring Chemical Analysis, 1st Edition (by Daniel C. Harris)

    NASA Astrophysics Data System (ADS)

    Wright, John C.

    1998-01-01

    W. H. Freeman: New York, 1997. ISBN: 0716730421. $80.00. Daniel Harris's book Quantitative Chemical Analysis is one of the 1000-pound gorillas for introductory analytical chemistry, both because of its dominance in the field and its size and information content. Students find the writing informal, interesting, and clear. Faculty like the completeness of the book and its sound treatment of the subject matter. It contains everything that an introductory analytical course could possibly want. Daniel Harris's recent book, Exploring Chemical Analysis, is a tamed version of the 1000-pound gorilla for nonchemistry majors. Students will find the same informality, interest, and clarity as in the earlier text but they will also find the book a comfortable companion. Faculty will find an abbreviated but excellent treatment of the subject matter. It contains most of the things that an introductory nonmajors analytical course should want.

  12. Device for high spatial resolution chemical analysis of a sample and method of high spatial resolution chemical analysis

    DOEpatents

    Van Berkel, Gary J.

    2015-10-06

    A system and method for analyzing a chemical composition of a specimen are described. The system can include at least one pin; a sampling device configured to contact a liquid with a specimen on the at least one pin to form a testing solution; and a stepper mechanism configured to move the at least one pin and the sampling device relative to one another. The system can also include an analytical instrument for determining a chemical composition of the specimen from the testing solution. In particular, the systems and methods described herein enable chemical analysis of specimens, such as tissue, to be evaluated in a manner that the spatial-resolution is limited by the size of the pins used to obtain tissue samples, not the size of the sampling device used to solubilize the samples coupled to the pins.

  13. Influence of chemical and environmental stresses on metal-binding proteins: Species-dependent effects

    SciTech Connect

    Baer, K.N.

    1988-01-01

    The development of tolerance to cadmium toxicity was investigated in mammals. In adult mice pretreated with 20 mg Cd/kg, no mortality was observed following administration of a 100 mg/kg cadmium challenge dose. In animals receiving prior exposure to cold stress a mortality of 40% was observed, while in animals receiving no pretreatment an 80% mortality was observed following cadmium challenge. Analysis of the metal-binding proteins using G-75 gel-filtration chromatography revealed that MT-like protein was responsible, in part, for the observed tolerance to cadmium toxicity. For example, following 20 mg Cd/kg and cold pretreatment, the MT-like reserve capacity was 56 and 42 nmoles cadmium, respectively, compared to a control value of 12 nmoles cadmium. The influence of pretreatments on the subcellular distribution of cadmium was also examined. The influence of chemical and environmental stresses on metal-binding proteins in teleosts was investigated. Following cadmium exposure, cadmium increased in the MT fraction in both the gill and liv