Sample records for nepheline formation potential


    Energy Technology Data Exchange (ETDEWEB)

    Amoroso, J.


    Sixteen glass compositions were selected to study the potential impacts of the kinetics of nepheline formation in high-level nuclear waste (HLW) glass. The chosen compositions encompassed a relatively large nepheline discriminator (ND) range, 0.40-0.66, and included a relatively broad range, and amount of, constituents including high aluminum and high boron concentrations. All glasses were fabricated in the laboratory and subsequently exposed to six different cooling treatments. The cooling treatments consisted of three 'stepped' profiles and their corresponding 'smooth' profiles. Included in the cooling treatment was the Defense Waste Processing Facility (DWPF) canister centerline cooling (CCC) profile in addition to a 'faster' and a 'slower' total cooling line. After quenching and heat treating, x-ray diffraction confirmed the type and amount of any resultant crystallization. The target compositions were shown to be consistent with the measured compositions. Two quenched glasses and several treated glasses exhibited minor amounts of spinel and spinel-like phases. Nepheline was not observed in any of the quenched glasses but was observed in many of the treated glasses. The amount of nepheline ranged from approximately 2wt% to 30wt% for samples cooled over shorter times and longer times respectively. Differences were observed in the amount of nepheline crystallization after smooth and stepped cooling and increased with total cooling time. In some glasses, nepheline crystallization appeared to be directly proportional to total cooling time while the total amount of nepheline crystallization varied, suggesting that the nepheline crystallization rate was independent of (or at least faster than) cooling rate but, varied depending on the glass composition. On the contrary, in another glass, nepheline crystallization appeared to be inversely proportional to cooling rate. The high alumina glasses, predicted to form nepheline

  2. Nepheline formation in chondrite parent bodies: Verification through experiments (United States)

    Ichimura, Shun; Seto, Yusuke; Tomeoka, Kazushige


    Nepheline is present as fine grains mainly in refractory inclusions and chondrules in CV and CO carbonaceous chondrites. The nepheline has been formed primarily by replacement of melilite and plagioclase in refractory inclusions and plagioclase and glass in chondrules. The nepheline formation is thought to have occurred during aqueous alteration and thermal metamorphism in the meteorite parent bodies. To verify this hypothesis, we performed the following experiments. Hydrothermal experiments of gehlenite (Al-rich melilite) and plagioclase (An48) were carried out at 200 °C and ∼15 bar for 168 h using solutions of pH 0, 7, 13, and 14 with a uniform Na concentration. In the gehlenite experiments, various amounts of SiO2 were added. The results revealed that a Na zeolite, analcime, was produced from 10/3 and 10/6 mixtures of gehlenite/SiO2 at pH 7, 13, and 14, and from a 10/10 mixture of gehlenite/SiO2 and plagioclase at pH 13 and 14. In particular, at pH 14, in addition to analcime, significant amounts of two other zeolites, fabriesite and hydroxycancrinite, were produced from the 10/6 mixture of gehlenite/SiO2, and fabriesite from plagioclase. Isothermal heating experiments for 24 h showed that fabriesite, hydroxycancrinite, and analcime transform to nepheline at 600-650, 550-600, and 750-800 °C, respectively. Differential thermal analysis of these zeolites revealed that fabriesite and hydroxycancrinite exhibit exothermic peaks, which correspond to transformation to nepheline, and that the temperatures of those peaks decrease steadily with decreasing heating rate. Kinetic analysis using these data revealed that fabriesite transforms to nepheline at 102 yr and hydroxycancrinite transforms to nepheline at 1 yr. Analcime heated non-isothermally at a rate of 1 °C/min transformed to nepheline at temperature higher than that determined by the isothermal experiments, suggesting that its transformation temperature also decreases if it is heated for a much longer

  3. Nepheline Formation Study for Sludge Batch 4 (SB4): Phase 1 Experimental Results

    Energy Technology Data Exchange (ETDEWEB)

    Peeler, D. K.; Edwards, T. B.; Reamer, I.A.; Workman, R. J.


    Although it is well known that the addition of Al{sub 2}O{sub 3} to borosilicate glasses enhances the durability of the waste form (through creation of network-forming tetrahedral Na+-[AlO{sub 4/2}]{sup -} pairs), the combination of high Al{sub 2}O{sub 3} and Na{sub 2}O can lead to the formation of nepheline (NaAlSiO{sub 4})--which can negatively impact durability. Given the projected high concentration of Al{sub 2}O{sub 3} in SB4 (Lilliston 2005) and the potential use of a high Na{sub 2}O based frit to improve melt rate and a high Na{sub 2}O sludge due to settling problems, the potential formation of nepheline in various SB4 systems continues to be assessed. Twelve SB4-based glasses were fabricated and their durabilities (via the Product Consistency Test [PCT]) measured to assess the potential for nepheline formation and its potential negative impact on durability. In terms of ''acceptability'', the results indicate that all of the study glasses produced are acceptable with respect to durability as defined by the PCT (normalized boron release values for all nepheline (NEPH) glasses were much lower than that of the Environmental Assessment (EA) glass (16.695 g/L)). The most durable glass is NEPH-04 (quenched) with a normalized boron release (NL [B]) of 0.61 g/L, while the least durable glass is NEPH-01 centerline canister cooled (ccc) with an NL [B] of 2.47 g/L (based on the measured composition). In terms of predictability, most of the study glasses are predictable by the {Delta}G{sub p} model. Those that are not predictable (i.e., they fall outside of the prediction limits) actually fall below the prediction interval (i.e., they are over predicted by the model) suggesting the model is conservative. The Phase 1 PCT results suggest that for those glasses prone to nepheline formation (using the 0.62 value developed by Li et al. (2003) as a guide), a statistically significant difference in PCT response was observed for the two heat treatments but

  4. Examining the role of canister cooling conditions on the formation of nepheline from nuclear waste glasses

    Energy Technology Data Exchange (ETDEWEB)

    Christian, J. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)


    Nepheline (NaAlSiO₄) crystals can form during slow cooling of high-level waste (HLW) glass after it has been poured into a waste canister. Formation of these crystals can adversely affect the chemical durability of the glass. The tendency for nepheline crystallization to form in a HLW glass increases with increasing concentrations of Al₂O₃ and Na₂O.

  5. Examining the role of canister cooling conditions on the formation of nepheline from nuclear waste glasses

    Energy Technology Data Exchange (ETDEWEB)

    Christian, J. H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)


    Nepheline (NaAlSiO₄) crystals can form during slow cooling of high-level waste (HLW) glass after it has been poured into a waste canister. Formation of these crystals can adversely affect the chemical durability of the glass. The tendency for nepheline crystallization to form in a HLW glass increases with increasing concentrations of Al₂O₃ and Na₂O.


    Energy Technology Data Exchange (ETDEWEB)

    Fox, K; Tommy Edwards, T


    Twenty five glass compositions were selected for a Phase II study to assess the potential for reducing the conservatism in the nepheline discriminator. The glass compositions were restricted to regions that fell within the validation ranges of the DWPF PCCS models. In addition, the liquidus temperature model was used to restrict the glass compositions so that they could all be melted at the same temperature. The nepheline discriminator was used to force the glass compositions into regions where nepheline formation was predicted to occur. The glasses were fabricated in the laboratory and characterized for crystallization and chemical durability after both quenching and slow cooling. Chemical analysis showed that the fabricated glasses met the target compositions. Nepheline was identified in one of the quenched glasses and several of the CCC glasses. There was no clear relationship between the types of crystallization that occurred in a particular glass and its location on the Al{sub 2}O{sub 3}-Na{sub 2}O-SiO{sub 2} ternary diagram. A partitioning algorithm was used to identify trends in crystallization behavior based on glass composition. Generally, for the CCC glasses MnO influenced the crystallization of spinels and B{sub 2}O{sub 3} and SiO{sub 2} influenced the crystallization of nepheline. Measured durability responses varied from acceptable to unacceptable depending on the glass composition and type and extent of crystallization that occurred. It was not possible to identify any linear effects of composition on chemical durability performance for this set of study glasses. The results were not sufficient to recommend modification of the current nepheline discriminator at this time. It is recommended that the next series of experiments continue to focus not only on compositional regions where the PCCS models are considered applicable (i.e., the model validation ranges), but also be restricted to compositional regions where acceptable glasses are predicted to be

  7. Optical Basicity and Nepheline Crystallization in High Alumina Glasses

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, Carmen P.; McCloy, John S.; Schweiger, M. J.; Crum, Jarrod V.; Winschell, Abigail E.


    The purpose of this study was to find compositions that increase waste loading of high-alumina wastes beyond what is currently acceptable while avoiding crystallization of nepheline (NaAlSiO4) on slow cooling. Nepheline crystallization has been shown to have a large impact on the chemical durability of high-level waste glasses. It was hypothesized that there would be some composition regions where high-alumina would not result in nepheline crystal production, compositions not currently allowed by the nepheline discriminator. Optical basicity (OB) and the nepheline discriminator (ND) are two ways of describing a given complex glass composition. This report presents the theoretical and experimental basis for these models. They are being studied together in a quadrant system as metrics to explore nepheline crystallization and chemical durability as a function of waste glass composition. These metrics were calculated for glasses with existing data and also for theoretical glasses to explore nepheline formation in Quadrant IV (passes OB metric but fails ND metric), where glasses are presumed to have good chemical durability. Several of these compositions were chosen, and glasses were made to fill poorly represented regions in Quadrant IV. To evaluate nepheline formation and chemical durability of these glasses, quantitative X-ray diffraction (XRD) analysis and the Product Consistency Test were conducted. A large amount of quantitative XRD data is collected here, both from new glasses and from glasses of previous studies that had not previously performed quantitative XRD on the phase assemblage. Appendix A critically discusses a large dataset to be considered for future quantitative studies on nepheline formation in glass. Appendix B provides a theoretical justification for choice of the oxide coefficients used to compute the OB criterion for nepheline formation.


    Energy Technology Data Exchange (ETDEWEB)

    Fox, K; James Newell, J; Tommy Edwards, T; David Best, D; Irene Reamer, I; Phyllis Workman, P


    The performance of a glass used for immobilization of high-level nuclear waste (HLW) is generally quantified by its resistance to chemical degradation, or durability. The durability of a HLW glass is dependent on its composition. If crystalline phases form within a glass during cooling, the composition of the residual glass network is altered, therefore affecting the durability of the glass. Crystallization of nepheline (NaAlSiO{sub 4}) has been shown to adversely impact the durability of HLW glasses since it removes glass forming species (in this case, Al and Si) from the glass network. The propensity for nepheline crystallization in a HLW glass increases with increasing concentrations of Al{sub 2}O{sub 3} and Na{sub 2}O in the glass. Nepheline crystallization is therefore of concern for processing of HLW at the Defense Waste Processing Facility (DWPF) since the sludge waste streams at the Savannah River Site (SRS) can contain high concentrations of Al{sub 2}O{sub 3} and Na{sub 2}O. Currently, a 'nepheline discriminator' is included as a process control constraint at the DWPF. The nepheline discriminator relates the concentrations of SiO{sub 2}, Na{sub 2}O and Al{sub 2}O{sub 3} (as weight percentages in glass) to a critical value of 0.62. The discriminator defines a boundary line on the SiO{sub 2}-Na{sub 2}O-Al{sub 2}O{sub 3} ternary diagram above which (or toward the SiO{sub 2} corner of the ternary) nepheline is not predicted to crystallize in the glass upon quenching or slow cooling. The current equation uses only the concentrations of the SiO{sub 2}, Na{sub 2}O and Al{sub 2}O{sub 3} components in the glass in predicting whether or not nepheline is likely to crystallize. However, several other components have been shown to impact the propensity for nepheline crystallization, including B{sub 2}O{sub 3} and CaO among others. Therefore, the potential exists to further refine the nepheline discriminator to include these components. In addition, recently


    Energy Technology Data Exchange (ETDEWEB)

    Fox, K.; Edwards, T.


    This study is the third phase in a series of experiments designed to reduce conservatism in the model that predicts the formation of nepheline, a crystalline phase that can reduce the durability of high level waste glass. A Phase I study developed a series of glass compositions that were very durable while their nepheline discriminator values were well below the current nepheline discriminator limit of 0.62, where nepheline is predicted to crystallize upon slow cooling. A Phase II study selected glass compositions to identify any linear effects of composition on nepheline crystallization and that were restricted to regions that fell within the validation ranges of the Defense Waste Processing Facility (DWPF) Product Composition Control System (PCCS) models. However, it was not possible to identify any linear effects of composition on chemical durability performance for this set of study glasses. The results of the Phase II study alone were not sufficient to recommend modification of the current nepheline discriminator. It was recommended that the next series of experiments continue to focus not only on compositional regions where the PCCS models are considered applicable (i.e., the model validation ranges), but also be restricted to compositional regions where the only constraint limiting processing is the current nepheline discriminator. Two methods were used in selecting glasses for this Phase III nepheline study. The first was based on the relationship of the current nepheline discriminator model to the other DWPF PCCS models, and the second was based on theory of crystallization in mineral and glass melts. A series of 29 test glass compositions was selected for this study using a combination of the two approaches. The glasses were fabricated and characterized in the laboratory. After reviewing the data, the study glasses generally met the target compositions with little issue. Product Consistency Test results correlated well with the crystallization analyses in


    Energy Technology Data Exchange (ETDEWEB)

    Fox, K.; Edwards, T.


    A series of 29 test glass compositions were selected for Phase III of the nepheline study using a combination of two approaches. The first approach was based on evaluating the glass composition region allowable by all of the Defense Waste Processing Facility (DWPF) Product Composition Control System (PCCS) models with the exception of the current nepheline discriminator. This approach was taken to determine whether there are glass compositions that, while predicted to crystallize nepheline upon slow cooling, would otherwise be acceptable for processing in the DWPF. The second approach was based on quasicrystalline theory of glass structure, which helped predict compositional regions where nepheline should form. A detailed description of this methodology is forthcoming. The selection strategy outlined here will provide an opportunity to determine experimentally whether the glasses that fail the current nepheline discriminator but pass the newly proposed nepheline discriminator are indeed free of nepheline after slow cooling. If this is the case, these data will serve as a significant step toward reducing conservatism in the current nepheline discriminator. The 29 glass compositions selected for testing address both the PCCS model and quasicrystalline theory approaches in evaluating both a reduction in conservatism for the current nepheline discriminator and possible implementation of the newly proposed discriminator based on glass structural theory. These glasses will be fabricated and characterized in the laboratory, with the results and conclusions described in a technical report.

  11. Pioneer fauna of nepheline-containing tailings (United States)

    Zenkova, I. V.; Kalmykova, V. V.; Liskovaya, A. A.


    The zoological analysis of nepheline-containing sands deposited in tailings 10-40 years ago showed that the pioneer colonists of this technogenic substrate are collembolan and mites, whose proportions depend on the succession of the bacterial and fungal components of the microbiota. The pioneer groups of mesofauna on 10- to 30-year-old tailings include carnivorous herpetobiontic arthropods and phytophagous insects. An impoverished version of the fauna of northern-taiga podzols is developed in the sands rehabilitated more than 40 years ago.

  12. Research of Geochemical Associations of Nephelin Ores (United States)

    Vulf, M.; Simonov, K.; Sazonov, A.

    The instant paper concerns research of distribution petrogenic chemical members in urtit ore body of Kia-Shaltyrsk deposit. Rocks of the deposit are ore for producing alum earth. Actuality of the subject based on outlooks of detection noble metal ore-bearing (Au, Pt, Pd, Rh, Ru) in alkaline rocks of Siberia, including rocks of Kia-Shaltyrsk deposit (Kuznetsk Alatau). The main purpose of analysis of distribution of members is directed to detection of a non-uniformity of distribution of substance and segments enriched with alum earth and noble members. The basic solved problems are following: o Creation regression models of ore body; o Definition of cumulative distribution functions of members in a contour of ore body; o The analysis of the obtained outcomes in geologic terms. For construction regression models the full-scale data was used, which was presented by the results of the spectral and silicate analyses of gold and petrogenic members containing 130 assays arranged in ore body. A non-linear multiparameter model of the ore body based on components of nephelin ore using neural net approach was constructed. For each member the corresponding distribution function is produced. The model is constructed on the following members: Au, Al2O3, SiO2, Fe2O3, CaO, MgO, SO3, R2O ((Na2O+K2O) -1) and losses of burning. The error of model forecasting membersS concentrations was from 0.02 up to 20%. Large errors basically connected with assays located near contact of ore body and ad- jacent strata or with very high concentrations of members; also they can be connected with different genesis of rocks or superposition of other processes. The analysis of concentrations of members and normalised absolute errors of the fore- cast has shown, that all members can be sectioned into two groups: first: Al2O3, SiO2, R2O, Fe2O3 and second: Au, losses of burning, CaO, MgO, SO3. The distribution of 1 gold is tightly connected with calcium and losses of burning and spatially linked with zones

  13. Nepheline structural and chemical dependence on melt composition

    Energy Technology Data Exchange (ETDEWEB)

    Marcial, José; Crum, Jarrod; Neill, Owen; McCloy, John


    Nepheline crystallizes upon slow-cooling in some melts concentrated in Na2O and Al2O3, which can result in a residual glass phase of low chemical durability. Nepheline can incorporate many components often found in high-level waste radioactive borosilicate glass, including glass network ions (e.g., Si, Al, Fe), alkali metals (e.g., Cs, K, Na, and possibly Li), alkaline-earth metals (e.g., Ba, Sr, Ca, Mg), and transition metals (e.g., Mn, and possibly Cr, Zn, Ni). When crystallized from melts of different compositions, nepheline chemistry varies as a function of starting glass composition. Five simulated high level nuclear waste borosilicate glasses shown to crystallize large fractions of nepheline on slow cooling, were selected for study. These melts constituted a range of Al2O3, B2O3, CaO, Na2O, K2O, Fe2O3, and SiO2 compositions. Compositional analyses of nepheline crystals in glass by electron probe micro-analysis (EPMA) indicate that boron is unlikely to be present in any significant concentration, if at all, in nepheline. Also, several models are presented for calculating the fraction of vacancies in the nepheline structure.

  14. Mineralogy and geochemistry of REE-Zr-Nb mineralised nepheline syenites in the peralkaline Ilímaussaq complex, South Greenland

    DEFF Research Database (Denmark)

    Borst, Anouk Margaretha

    -related Gardar province and comprises a series of highly unusual magmatic rocks described as agpaitic nepheline syenites. Agpaitic rocks are characterised by the presence of complex Na-Zr-Ti-silicates such as eudialyte and rinkite instead of common accessory Zr and Ti minerals like zircon and titanite....... The present study focusses on the lower part of the magmatic sequence in the southern part of the complex (Kringlerne), comprising a c. 250 m thick sequence of spectacularly layered syenites called kakortokites. The kakortokites are of particular interest for their enrichment in Zr, Nb, Ta and REE, largely...... potential of these rocks. It is shown that widespread hydrothermal alteration of primary magmatic eudialyte has led to the formation of fine-grained intergrowths of secondary Zr, Nb and REE phases. The alteration was not associated with significant loss or gain of the valuable metals, although the increased...

  15. Applied gamma ray spectrometry and remote sensing in delineation of nepheline syenites in rift tectonic settings (United States)

    Chiwona, Annock Gabriel; Manning, David A. C.; Gaulton, Rachel; Cortes, Joaquin A.


    The United Nations (2016) observes that 'Neglected Development Minerals' including industrial minerals such as nepheline syenites have great potential for sustainable development, yet their exploitation has not been equally promoted like high value minerals. Nepheline syenites have great potential as alternative potassium (K) silicate fertiliser, as well as a source of Rare Earths. Demand for K fertiliser keeps rising by 3-3.5% annually (Jena et al., 2014) due to increased need to replace K removal from the soil (Sheldrick et al., 2002). The situation is most critical in Sub-Sahara Africa where nutrient loss due to intensive farming accounts to 22kg N, 2.5 kg P and 15 kg of K per hectare annually (Keeble, 2012). Ironically, Africa with 15% of global population, which is also expected to double by 2040 (Manning, 2015), uses only 1.5% of global K fertiliser. In this study, we use recently acquired countrywide airborne geophysical gamma ray data of Malawi (Bates & Mechennef, 2013) and satellite remote sensing data to identify nepheline syenites, suitable as sources of K silicate fertilizer, in rift tectonic settings. Initial focus was on the East African Rift System (EARS) starting with Malawi. Results from these two techniques are compared with X-ray fluorescence (XRF) geochemical analyses of sample collected from fieldwork in some potential areas of Malawi. With lessons from the Rochagem movement (Theodoro & Leonardos, 2006), identification of novel alternative potash sources in Africa will greatly benefit millions of farmers in developing countries, especially in Sub Sahara Africa where fertiliser costs are very high. Considering that high-resolution airborne geophysical data is not available in many African countries due to high costs associated with data acquisition campaigns, alternative and effective remote sensing approaches for delineating nepheline syenite rocks are necessary. References: [1] Bates M & Mechennef, F (2013) Data Acquisition Report, Sander

  16. Cambrian nepheline syenite complex at Jabal Sawda, Midyan region, Kingdom of Saudi Arabia (United States)

    Liddicoat, W.K.; Ramsay, C.R.; Hedge, C.E.


    The only nepheline syenite complex presently known in the Arabian Shield is at Jabal Sawda, about 30 km S of Haql in the extreme NW of Saudi Arabia. It is a post-tectonic, composite intrusion with a crudely concentric structure. A core of leuco-nepheline syenite, a partial ring of mela-nepheline syenite, and an almost complete outer ring of alkali-feldspar syenite are the main rock units. Several mega-inclusions of porphyritic nepheline syenite, nepheline monzosyenite, malignite and ijolite are present in the leuco-nepheline syenite. The chemical composition is notable for very high values of Al2O3, Na2O, Ba, La, Nb, Sr and Zr. U{single bond}Pb isotope dating indicates an emplacement age of 553 ?? 4 Ma, one of an increasing number of reliable Cambrian isotope dates in the northern Red Sea region. ?? 1986.

  17. Mössbauer investigation of a nepheline substrate used for preparing a water treatment reagent (United States)

    Filippov, V. P.; Feklistov, D. Yu.; Kurchatov, I. M.; Laguntsov, N. I.; Salomasov, V. A.; Permyakov, Yu. V.


    The aim of this work is to reveal the results of the reaction of nepheline mineral with concentrated sulfuric acid. The valence states of iron atoms are determined in the nepheline and the reacted nepheline. The existence of iron containing magnetic particles in the sediment is shown. The differences in the lineshape are discussed also and are associated with a transfer from one phase to another of the magnetic particles.

  18. Mössbauer investigation of a nepheline substrate used for preparing a water treatment reagent

    Energy Technology Data Exchange (ETDEWEB)

    Filippov, V. P., E-mail:; Feklistov, D. Yu.; Kurchatov, I. M.; Laguntsov, N. I. [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute) (Russian Federation); Salomasov, V. A. [JSC Aquaservice (Russian Federation); Permyakov, Yu. V. [Russian Metrological Institute of Technical Physics and Radio Engineering (Russian Federation)


    The aim of this work is to reveal the results of the reaction of nepheline mineral with concentrated sulfuric acid. The valence states of iron atoms are determined in the nepheline and the reacted nepheline. The existence of iron containing magnetic particles in the sediment is shown. The differences in the lineshape are discussed also and are associated with a transfer from one phase to another of the magnetic particles.

  19. Potential Maximizers and Network Formation

    NARCIS (Netherlands)

    Slikker, M.; Dutta, P.K.; van den Nouweland, C.G.A.M.; Tijs, S.H.


    In this paper we study the formation of cooperation structures in superadditive cooperative TU-games.Cooperation structures are represented by hypergraphs.The formation process is modelled as a game in strategic form, where the payoffs are determined according to a weighted (extended) Myerson value.

  20. Cancrinite from nepheline syenite (mariupolite) of the Oktiabrski massif, SE Ukraine, and its growth history (United States)

    Dumańska-Słowik, Magdalena; Pieczka, Adam; Heflik, Wiesław; Sikorska, Magdalena


    Secondary cancrinite, (Na5.88K< 0.01)∑ 5.88(Ca0.62 Fe0.01Mn0.01Zn< 0.01 Mg< 0.01)∑ 0.64[Si6.44Al 5.56O24](CO3)0.67(OH)0.26(F< 0.01,Cl< 0.01)·2.04H2O), was found as accessory component of mariupolite (albite-aegirine nepheline syenite) from the Oktiabrski massif in the Donbass (SE Ukraine). It probably crystallized from a subsolidus reaction involving nepheline (and sodalite?) and calcite dissolved in the aqueous-carbonic fluid at the maximum temperature of 930 °C, decreasing to hydrothermal conditions. It is depleted in sodium, calcium and carbon, what results in the occurrence of vacant positions at both cationic and anionic sites. Ca-deficient cancrinite crystallized from the same hydrothermal Si-undersaturated fluids enriched in the ions such as Na+, Ca2 +, Cl-, F-, HCO3-, which formed calcite, sodalite, natrolite and fluorite. It has dark-red CL colours with patchy zoning, what indicates the variable/diverse fluid composition during its formation. In the CL spectrum of cancrinite only one broad emission band at 410 nm is observed, which can be attributed to O* center (the recombination of a free electron with an O- hole center). The formation of secondary CO3-rich species, i.e. cancrinite and calcite in mariupolite suggests that redox conditions in the Oktiabrski massif were oxidizing at the postmagmatic stage.

  1. Excess Pu disposition in zirconolite-rich Synroc containing nepheline

    Energy Technology Data Exchange (ETDEWEB)

    Vance, E.R.; Hart, K.P.; Day, R.A.; Begg, B.D.; Angel, P.J.; Loi, E.; Weir, J. [ANSTO, Menai, New South Wales (Australia); Oversby, V.M. [Lawrence Livermore Nation Lab., CA (United States)


    A titanate Synroc ceramic for the immobilization of Pu-bearing waste was designed to consist of 70 wt% zirconolite (CaZrTi{sub 2}O{sub 7}) + 15 wt% nepheline (NaAlSiO{sub 4}) + 15 wt% rutile (TiO{sub 2}). It contained 10 wt% of Pu plus 6 wt% of Gd as a neutron poison. The material was made by the standard sol-gel route, using a mixture of alkoxides and nitrates, followed by stir-drying and calcination. It was fabricated by hot-pressing at 1,150--1,250 C/20 MPa for 2 hours in a collapsible metal bellows. Though zirconolite was the majority phase, {approximately} 20 wt% of perovskite also formed. Some of the Na, intended for nepheline, partitioned into the titanate phases. 84-day differential total leach rates of Pu were in the order of 10{sup {minus}5} g/m{sup 2}/d at 90 and 200 C. Companion ceramics using molar substitution of Ce for Pu confirmed the idea that Ce is a good simulant of Pu from a solid state chemical view, but that there are limitations in terms of leach rate parallels.

  2. Crystal chemistry of nephelines from ijolites and nepheline-rich pegmatites: influence of composition and genesis on the crystal structure investigated by X-ray diffraction

    DEFF Research Database (Denmark)

    Vulić, Predrag; Balić-Žunić, Tonči; Belmonte, Louise Josefine;


    some degree of disorder in the Si/Al distribution. Most of the samples revealed a practically full Si-Al-ordering, but the crystals from one of the nepheline-syenite pegmatites in Langesundsfjord, Norway and from the type locality of ijolite, Iivaara, Finland, showed a disorder of 10–20% suggesting...

  3. Crystal chemistry of nephelines from ijolites and nepheline-rich pegmatites: influence of composition and genesis on the crystal structure investigated by X-ray diffraction

    DEFF Research Database (Denmark)

    Vulic, Predrag; Balic Zunic, Tonci; Belmonte, Louise Josefine;


    some degree of disorder in the Si/Al distribution. Most of the samples revealed a practically full Si-Alordering, but the crystals from one of the nepheline-syenite pegmatites in Langesundsfjord, Norway and from the type locality of ijolite, Iivaara, Finland, showed a disorder of 10–20% suggesting...

  4. Sputtering of sodium and potassium from nepheline: Secondary ion yields and velocity spectra (United States)

    Martinez, R.; Langlinay, Th.; Ponciano, C. R.; da Silveira, E. F.; Palumbo, M. E.; Strazzulla, G.; Brucato, J. R.; Hijazi, H.; Agnihotri, A. N.; Boduch, P.; Cassimi, A.; Domaracka, A.; Ropars, F.; Rothard, H.


    Silicates are the dominant surface material of many Solar System objects, which are exposed to ion bombardment by solar wind ions and cosmic rays. Induced physico-chemical processes include sputtering which can contribute to the formation of an exosphere. We have measured sputtering yields and velocity spectra of secondary ions ejected from nepheline, an aluminosilicate thought to be a good analogue for Mercury's surface, as a laboratory approach to understand the evolution of silicate surfaces and the presence of Na and K vapor in the exosphere. Experiments were performed with highly charged ion beams (keV/u-MeV/u) delivered by GANIL using an imaging XY-TOF-SIMS device under UHV conditions. The fluence dependence of sputtering yields gives information about the evolution of surface stoichiometry during irradiation. From the energy distributions N(E) of sputtered particles, the fraction of particles which could escape from the gravitational field of Mercury, and of those falling back and possibly contributing to populate the exosphere can be roughly estimated.

  5. Investigation of fugitive dust emissions from nepheline syenite mine tailings near Nephton, Ontario (United States)

    Ogungbemide, Damilare Immanuel

    A set of experiments was designed to investigate the factors--atmospheric and surficial--controlling fugitive dust emissions from the tailings ponds of UNIMIN Canada, a mining company that extracts and produces nepheline syenite (feldspar) at two adjacent sites (Nephton and Blue Mountain) located north of Havelock, Ontario. Using wind tunnel measurements, the combined influence of relative humidity and temperature (represented by the absolute matric potential, |psi|) on dust emission was quantified and modeled. About 300 experimental runs were conducted under various conditions of wind speed (4.5-6.25 ms -1), temperature (0-30°C) and relative humidity (10-70%). Generally, dust flux decreased as a logarithmic function of matric potential, with dust emission strongly suppressed for RH > 60% or |psi|climate and topographic conditions found at their sites, and also serve as a source of useful information and input data for atmospheric dispersion models, such as AERMOD and CALPUFF, whose accuracy depends on the quality of the input data such as the emission rate.

  6. Melanite garnet-bearing nepheline syenite minor intrusion in Mawpyut ultramafic–mafic complex, Jaintia Hills, Meghalaya

    Indian Academy of Sciences (India)

    Monoj Maitra; J S David; S Bhaduri


    Mawpyut igneous suite in Jaintia Hills of Meghalaya plateau comprises differentiated suite of ultramafic–mafic rocks. The complex differs from other ultramafic–alkaline–carbonatite igneous emplacements of Shillong plateau and Mikir Hills like Jesra, Sung, Samchampi complexes, by the absence of alkaline–carbonatite rocks as major litho-units. Melanite garnet-bearing nepheline syenite, occurs as late phase minor intrusion in Mawpyut igneous complex, posseses alkaline character and shows inubiquitous relation with the host ultramafic–mafic rocks. On the other hand, this alkaline intrusive bodies of the Mawpyut igneous complex shows chemico-mineralogical resemblance with garnet-bearing nepheline syenite, ijolite litho-members of Jesra, Sung, Samchampi complexes of the region. It is interpreted that melanite garnet-bearing nepheline syenite intrusion in Mawpyut is contemporaneous with Jesra, Sung, Samchampi ultramafic–alkaline–carbonatite complexes and the host rocks of Mawpyut complex is an earlier magmatic activity possibly from a comparatively least enriched source.

  7. Quasicrystalline Approach to Prediting the Spinel-Nepheline Liquidus: Application to Nuclear Waste Glass Processing

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, Carol


    The crystal-melt equilibria in complex fifteen component melts are modeled based on quasicrystalline concepts. A pseudobinary phase diagram between acmite (which melts incongruently to a transition metal ferrite spinel) and nepheline is defined. The pseudobinary lies within the Al{sub 2}O{sub 3}-Fe{sub 2}O{sub 3}-Na{sub 2}O-SiO{sub 2} quaternary system that defines the crystallization of basalt glass melts. The pseudobinary provides the partitioning of species between the melt and the primary liquidus phases. The medium range order of the melt and the melt-crystal exchange equilibria are defined based on a constrained mathematical treatment that considers the crystallochemical coordination of the elemental species in acmite and nepheline. The liquidus phases that form are shown to be governed by the melt polymerization and the octahedral site preference energies. This quasicrystalline liquidus model has been used to prevent unwanted crystallization in the world's largest high level waste (HLW) melter for the past three years while allowing >10 wt% higher waste loadings to be processed.

  8. Formation of Intellectual Potential and Sustainable Development of Society

    Directory of Open Access Journals (Sweden)

    Nadezhda Gus'kova


    Full Text Available The article justifies the place and role of intellectual potential for the sustainable development of society. The intellectual potential is regarded as the most valuable strategic resource, and the main source of competitive advantage. The basis of intellectual potential is the knowledge, formed in the processes of learning, intellectual activity, awareness of gained personal experience and universal values. The formation of intellectual potential is connected with the establishment of new models of human behavior and system of values.

  9. Optimal schooling formations using a potential flow model (United States)

    Tchieu, Andrew; Gazzola, Mattia; de Brauer, Alexia; Koumoutsakos, Petros


    A self-propelled, two-dimensional, potential flow model for agent-based swimmers is used to examine how fluid coupling affects schooling formation. The potential flow model accounts for fluid-mediated interactions between swimmers. The model is extended to include individual agent actions by means of modifying the circulation of each swimmer. A reinforcement algorithm is applied to allow the swimmers to learn how to school in specified lattice formations. Lastly, schooling lattice configurations are optimized by combining reinforcement learning and evolutionary optimization to minimize total control effort and energy expenditure.

  10. Chemical composition analysis and product consistency tests supporting refinement of the Nepheline Model for the high aluminum Hanford glass composition region

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Edwards, T. B. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Mcclane, D. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)


    In this report, Savannah River National Laboratory provides chemical analyses and Product Consistency Test (PCT) results for a series of simulated high level waste (HLW) glasses fabricated by Pacific Northwest National Laboratory (PNNL) as part of an ongoing nepheline crystallization study. The results of these analyses will be used to improve the ability to predict crystallization of nepheline as a function of composition and heat treatment for glasses formulated at high alumina concentrations.

  11. Chemical composition analysis and product consistency tests supporting refinement of the Nepheline model for the high aluminum Hanford Glass composition region

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K. M. [Savannah River Site (SRS), Aiken, SC (United States); Edwards, T. B. [Savannah River Site (SRS), Aiken, SC (United States); Mcclane, D. L. [Savannah River Site (SRS), Aiken, SC (United States)


    In this report, SRNL provides chemical analyses and Product Consistency Test (PCT) results for a series of simulated HLW glasses fabricated by Pacific Northwest National Laboratory (PNNL) as part of an ongoing nepheline crystallization study. The results of these analyses will be used to improve the ability to predict crystallization of nepheline as a function of composition and heat treatment for glasses formulated at high alumina concentrations.

  12. Coffee melanoidins: structures, mechanisms of formation and potential health impacts. (United States)

    Moreira, Ana S P; Nunes, Fernando M; Domingues, M Rosário; Coimbra, Manuel A


    During the roasting process, coffee bean components undergo structural changes leading to the formation of melanoidins, which are defined as high molecular weight nitrogenous and brown-colored compounds. As coffee brew is one of the main sources of melanoidins in the human diet, their health implications are of great interest. In fact, several biological activities, such as antioxidant, antimicrobial, anticariogenic, anti-inflammatory, antihypertensive, and antiglycative activities, have been attributed to coffee melanoidins. To understand the potential of coffee melanoidin health benefits, it is essential to know their chemical structures. The studies undertaken to date dealing with the structural characterization of coffee melanoidins have shown that polysaccharides, proteins, and chlorogenic acids are involved in coffee melanoidin formation. However, exact structures of coffee melanoidins and mechanisms involved in their formation are far to be elucidated. This paper systematizes the available information and provides a critical overview of the knowledge obtained so far about the structure of coffee melanoidins, mechanisms of their formation, and their potential health implications.

  13. Reducing the potential for processing contaminant formation in cereal products. (United States)

    Curtis, Tanya Y; Postles, Jennifer; Halford, Nigel G


    Processing contaminants may be defined as substances that are produced in a food when it is cooked or processed, are not present or are present at much lower concentrations in the raw, unprocessed food, and are undesirable either because they have an adverse effect on product quality or because they are potentially harmful. The presence of very low levels of processing contaminants in common foods is becoming an increasingly important issue for the food industry, as developments in analytical techniques and equipment bring foods under closer and closer scrutiny. This review considers the formation of lipid oxidation products, hydrogenation of polyunsaturated fatty acids to prevent lipid oxidation and the associated risk of trans fatty acid formation. The formation of acrylamide in the Maillard reaction is described, as well as the genetic and agronomic approaches being taken to reduce the acrylamide-forming potential of cereal grain. The multiple routes for the formation of furan and associated chemicals, including hydroxymethylfurfuryl, are also described. The evolving regulatory and public perception situations for these processing contaminants and their implications for the cereal supply chain are discussed, emphasising the need for cereal breeders to engage with the contaminants issue.

  14. Secondary organic aerosols: Formation potential and ambient data

    DEFF Research Database (Denmark)

    Barthelmie, R.J.; Pryor, S.C.


    Organic aerosols comprise a significant fraction of the total atmospheric particle loading and are associated with radiative forcing and health impacts. Ambient organic aerosol concentrations contain both a primary and secondary component. Herein, fractional aerosol coefficients (FAC) are used...... in conjunction with measurements of volatile organic compounds (VOC) to predict the formation potential of secondary organic aerosols (SOA) in the Lower Fraser Valley (LEV) of British Columbia. The predicted concentrations of SOA show reasonable accord with ambient aerosol measurements and indicate considerable...

  15. Formation of runaway stars in a star-cluster potential (United States)

    Ryu, Taeho; Leigh, Nathan W. C.; Perna, Rosalba


    We study the formation of runaway stars due to binary-binary (2+2) interactions in young star-forming clusters and/or associations. This is done using a combination of analytic methods and numerical simulations of 2+2 scattering interactions, both in isolation and in a homogeneous background potential. We focus on interactions that produce two single stars and a binary, and study the outcomes as a function of the depth of the background potential, within a range typical of cluster cores. As reference parameters for the observational properties, we use those observed for the system of runaway stars AE Aur and μ Col and binary ι Ori. We find that the outcome fractions have no appreciable dependence on the depth of the potential, and neither do the velocities of the ejected single stars. However, as the potential gets deeper and a larger fraction of binaries remain trapped, two binary populations emerge, with the escaped component having higher speeds and shorter semimajor axes than the trapped one. Additionally, we find that the relative angles between the ejected products are generally large. In particular, the angle between the ejected fastest star and the escaped binary is typically ≳120°-135°, with a peak at around 160°. However, as the potential gets deeper, the angle distribution becomes broader. Finally, we discuss the implications of our results for the interpretation of the properties of the runaway stars AE Aur and μ Col.


    Directory of Open Access Journals (Sweden)

    M. L. Oliveira


    Full Text Available Introduction and objectives: Apps can be designed to provide usage data, and most of them do. These data are usually used to map users interests and to deliver more effective ads that are more likely to result in clicks, and sales. We have applied some of these metrics to understand how can it be used to map students’ behavior and to promote a formative assessment using educational software. The purpose of a formative assessment is to monitor student learning to provide ongoing feedback that can be used by instructors and students to improve the teaching and learning process. Thus, this modality aims to help both students and instructors to identify strengths and weaknesses that need to be developed. This study aimed to describe the potential of educational apps in the formative assessment process. Material and Methods: We have implemented assessment tools embedded in three apps (ARMET, The Cell and 3D Class used to teach: 1 Metabolic Pathways; 2 Scale of the cellular structures, and 3 Concepts from techniques used in a Biochemistry Lab course. The implemented tools allow to verify on what issues there were recurring mistakes, the total number of mistakes presented, which questions they most achieved, how long they took to perform the activity and other relevant information. Results and conclusion: Educational apps can provide transparent and coherent evaluation metrics to enable instructors to systematize more consistent criteria and indicators, reducing the subjectivity of the formative assessment process and the time spent for preparation, tabulation and analysis of assessment data. This approach allows instructors to understand better where students struggle, giving to them a more effective feedback. It also helps instructor to plan interventions to help students to perform better and to achieve the learning objectives.

  17. Influence of nepheline syenite and milling time on the rheological properties of a porcelain stoneware tile slip

    Directory of Open Access Journals (Sweden)

    Jazayeri, S. H.


    Full Text Available The rheological properties of porcelain stoneware tile slips were investigated using a rotational rheometer. The first step in the study was to evaluate the rheological behaviour of a reference slip at different particle size distributions to determine the optimum conditions at which to carry out the investigation of the influence of nepheline syenite in the mix. In the second step part of the K-feldspar in the reference mix was replaced with nepheline syenite such that the mix composition contained 10 % nepheline syenite. The flow curve, yield stress and thixotropy of the slips were evaluated at different milling times in order to study the effect of particle size on the rheological behaviour. The milling times for the reference mix and for the mix with nepheline syenite which resulted in the best rheological parameters were found.

    Se han investigado las propiedades reológicas de barbotinas de porcelana dura para pavimentos usando un reómetro rotacional. El primer paso del estudio fue evaluar el comportamiento reológico de una barbotina de referencia con diferentes distribuciones de tamaño de partícula con el fin de determinar las condiciones óptimas bajo las cuales estudiar la influencia de nefelina sienita en la mezcla. En la segunda etapa, parte del feldespato potásico de la mezcla de referencia se substituyó por nefelina sienita de forma que la composición de la mezcla tuviera un 10% de neflina sienita. Se evaluaron las curvas de flujo, los puntos de fluidez y la tixotropía de las barbotinas tras diferentes tiempos de molienda con el fin de estudiar el efecto del tamaño de partícula en el comportamiento reológico. Se determinaron los tiempos de molienda en los que se alcanzaban los mejores parámetros reológicos para la mezcla de referencia y la de nefelina sienita.

  18. Barrier formation: potential molecular mechanism of enamel fluorosis

    NARCIS (Netherlands)

    Lyaruu, D.M.; Medina, J.F.; Sarvide, S.; Bervoets, T.J.M.; Everts, V.; Denbesten, P.; Smith, C.E.; Bronckers, A.L.J.J.


    Enamel fluorosis is an irreversible structural enamel defect following exposure to supraoptimal levels of fluoride during amelogenesis. We hypothesized that fluorosis is associated with excess release of protons during formation of hypermineralized lines in the mineralizing enamel matrix. We tested

  19. Barrier formation: potential molecular mechanism of enamel fluorosis

    NARCIS (Netherlands)

    Lyaruu, D.M.; Medina, J.F.; Sarvide, S.; Bervoets, T.J.M.; Everts, V.; Denbesten, P.; Smith, C.E.; Bronckers, A.L.J.J.


    Enamel fluorosis is an irreversible structural enamel defect following exposure to supraoptimal levels of fluoride during amelogenesis. We hypothesized that fluorosis is associated with excess release of protons during formation of hypermineralized lines in the mineralizing enamel matrix. We tested

  20. Trihalomethane formation potential of organic fractions in secondary effluent

    Institute of Scientific and Technical Information of China (English)

    XUE Shuang; ZHAO Qingliang; WEI Liangliang; JIA Ting


    Organic matter is known to be the precursor of numerous chlorination by-products. Organic matter in the secondary effluent from the Wenchang Wastewater Treatment Plant(Harbin. China)was physically separated into the following fractions: particulate organic carbon(1. 2-0. 45un), colloidal organic carbon(0. 45-0. 1um), fine colloidal organic carbon(0. 1-0. 025um), and dissolved organic carbon(DOC)(<0. 025um). Moreover, <0. 45 um fraction was chemically separated into hydrophobic acid(HPO-A), hydrophobic neutral(HPO-N), transphilic acid(TPI-A), transphilic neutral(TPI-N), and hydrophilic fraction(HPI). The chlorine reactivity of these organic fractions obtained from both size and XAD fractionations were evaluated. The structural and chemical compositions of the HPO-A. HPO-N. TPI-A. and TPI-N isolates were characterized using elemental analysis(C, H, 0, and N), Fourier trailsform infrared spectroscopy(FT-IR), and proton nuclear magnetic resonance spectroscopy(1H-NMR). Results showed that Doe was dominant in terms of total concentration and trihalomethane formation potential(THMFP). and there was no statistical difference in both specific THMFP(STHMFP)and specific ultraviolet light absorbance among the 0. 45, 0. 1, and 0. 025 um filtrates. HPO-A had the highest STHMFP compared to other chemical fractions. HPO-A, HPO-N, TPI-A, and TPI-N contained 3. 02%-3. 52%of nitrogen. The molar Ratio of H/C increased in the order of HPO. A

  1. Geochronologic and petrochemical evidence for the genetic link between the Maomaogou nepheline syenites and the Emeishan large igneous province

    Institute of Scientific and Technical Information of China (English)

    LUO ZhenYu; XU YiGang; HE Bin; SHI YuRuo; HUANG XiaoLong


    The Maomaogou nepheline syenite is located at the inner zone of the Emeishan large igneous province and exhibits intrusive contact with the Emeishan basalts. SHRIMP U-Pb dating on zircons from this syenite yields an age of 261.6±4.4 Ma, in agreement with the age of the Panzhihua layered intrusion and the eruption age of the Emeishan basalts as constrained by stratigraphic data. Geochemical data further suggest that the Maomaogou syenite has a source analogue to the Emeishan basalt, and may have been formed by partial melting of gabbroic cumulates underplated in the lower crust. As s result, temporal and spatial relationships and petrogenetic constraints provide evidence for the genetic link between basalts, mafic/ultramafic and intermediate/acidic intrusives in the Panxi area.

  2. Collaborative learning through formative peer review: pedagogy, programs and potential (United States)

    Søndergaard, Harald; Mulder, Raoul A.


    We examine student peer review, with an emphasis on formative practice and collaborative learning, rather than peer grading. Opportunities to engage students in such formative peer assessment are growing, as a range of online tools become available to manage and simplify the process of administering student peer review. We consider whether pedagogical requirements for student peer review are likely to be discipline-specific, taking computer science and software engineering as an example. We then summarise what attributes are important for a modern generic peer review tool, and classify tools according to four prevalent emphases, using currently available, mature tools to illustrate each. We conclude by identifying some gaps in current understanding of formative peer review, and discuss how online tools for student peer review can help create opportunities to answer some of these questions.

  3. Chanco formation, a potential Cretaceous reservoir, central Chile

    Energy Technology Data Exchange (ETDEWEB)

    Cecione, G.


    The Chanco embayment lies 300 km SSW of Santiago, Chile. The sequence within this basin above the metamorphic basement is: Chanco Formation (very clean sandstone), Quiriquina Formation (glauconitic sandstone, rich in organic matter), and Navidad Group (a very good caprock). This section thus contains reservoir, source and caprocks, and is therefore very promising for petroleum investigations. The offshore C-1 well yielded salt-water with gas shows, and two wells drilled onshore yielded shows of gas. The C-1 well lies on a gently-dipping EW-striking anticlinal structure, the presence of which makes the area very prospective.

  4. Assessing the Potential for Nitrogen Bubble Formation in Diving Odontocetes (United States)


    first compartment within which exchange occurs is the blood pool, and assuming that cetacean hematological factors do not inhibit bubble formation...relationship between “bubble-like” cavitary lesions reported in the portal system of some stranding cetaceans , and the accessibility of these vessels...Dorian Houser served as the PI on project and was responsible for facilities coordination, animal welfare issues, ultrasound inspections and blood

  5. Emplacement kinematics of nepheline syenites from the Terrane Boundary Shear Zone of the Eastern Ghats Mobile Belt, west of Khariar, NW Orissa: Evidence from meso- and microstructures

    Indian Academy of Sciences (India)

    T K Biswal; Harish Ahuja; Himansu Sekhar Sahu


    Nepheline syenite plutons emplaced within the Terrane Boundary Shear Zone of the Eastern Ghats Mobile Belt west of Khariar in northwestern Orissa are marked by a well-developed magmatic fabric including magmatic foliation, mineral lineations, folds and S-C fabrics. The minerals in the plutons, namely microcline, orthoclase, albite, nepheline, hornblende, biotite and aegirine show, by and large, well-developed crystal faces and lack undulose extinction and dynamic recrystallization, suggesting a magmatic origin. The magmatic fabric of the plutons is concordant with a solid-state strain fabric of the surrounding mylonites that developed due to noncoaxial strain along the Terrane Boundary Shear Zone during thrusting of the Eastern Ghats Mobile Belt over the Bastar Craton. However, a small fraction of the minerals, more commonly from the periphery of the plutons, is overprinted by a solid state strain fabric similar to that of the host rock. This fabric is manifested by discrete shear fractures, along which the feldspars are deformed into ribbons, have undergone dynamic recrystallization and show undulose extinction and myrmekitic growth. The shear fractures and the magmatic foliations are mutually parallel to the C-fabric of the host mylonites. Coexistence of concordant solid state strain fabric and magmatic fabric has been interpreted as a transitional feature from magmatic state to subsolidus deformation of the plutons, while the nepheline syenite magma was solidifying from a crystal-melt mush state under a noncoaxial strain. This suggests the emplacement of the plutons synkinematic to thrusting along the Terrane Boundary Shear Zone. The isotopic data by earlier workers suggest emplacement of nepheline syenite at 1500 + 3/− 4Ma, lending support for thrusting of the mobile belt over the craton around that time.

  6. Potential formation of three pyrimidine bases in interstellar regions

    CERN Document Server

    Majumdar, Liton; Das, Ankan; Chakrabarti, Sandip K


    Work on the chemical evolution of pre-biotic molecules remains incomplete since the major obstacle is the lack of adequate knowledge of rate coefficients of various reactions which take place in interstellar conditions. In this work, we study the possibility of forming three pyrimidine bases, namely, cytosine, uracil and thymine in interstellar regions. Our study reveals that the synthesis of uracil from cytosine and water is quite impossible under interstellar circumstances. For the synthesis of thymine, reaction between uracil and :CH2 is investigated. Since no other relevant pathways for the formation of uracil and thymine were available in the literature, we consider a large gas-grain chemical network to study the chemical evolution of cytosine in gas and ice phases. Our modeling result shows that cytosine would be produced in cold, dense interstellar conditions. However, presence of cytosine is yet to be established. We propose that a new molecule, namely, C4N3OH5 could be observable in the interstellar ...

  7. Isoprene suppression of new particle formation: Potential mechanisms and implications (United States)

    Lee, Shan-Hu; Uin, Janek; Guenther, Alex B.; Gouw, Joost A.; Yu, Fangqun; Nadykto, Alex B.; Herb, Jason; Ng, Nga L.; Koss, Abigail; Brune, William H.; Baumann, Karsten; Kanawade, Vijay P.; Keutsch, Frank N.; Nenes, Athanasios; Olsen, Kevin; Goldstein, Allen; Ouyang, Qi


    Secondary aerosols formed from anthropogenic pollutants and natural emissions have substantial impacts on human health, air quality, and the Earth's climate. New particle formation (NPF) contributes up to 70% of the global production of cloud condensation nuclei (CCN), but the effects of biogenic volatile organic compounds (BVOCs) and their oxidation products on NPF processes in forests are poorly understood. Observations show that isoprene, the most abundant BVOC, suppresses NPF in forests. But the previously proposed chemical mechanism underlying this suppression process contradicts atmospheric observations. By reviewing observations made in other forests, it is clear that NPF rarely takes place during the summer when emissions of isoprene are high, even though there are sufficient concentrations of monoterpenes. But at present it is not clear how isoprene and its oxidation products may change the oxidation chemistry of terpenes and how NOx and other atmospheric key species affect NPF in forest environments. Future laboratory experiments with chemical speciation of gas phase nucleation precursors and clusters and chemical composition of particles smaller than 10 nm are required to understand the role of isoprene in NPF. Our results show that climate models can overpredict aerosol's first indirect effect when not considering the absence of NPF in the southeastern U.S. forests during the summer using the current nucleation algorithm that includes only sulfuric acid and total concentrations of low-volatility organic compounds. This highlights the importance of understanding NPF processes as function of temperature, relative humidity, and BVOC compositions to make valid predictions of NPF and CCN at a wide range of atmospheric conditions.

  8. Principles and factors of formation and use of the investment potential of the enterprise


    Bormotova, M.; Moskalenko, B.; Sukhorebryi, E.


    This article explores the principles and factors of formation and use of the investment potential of the enterprise. The authors found the most effective directions of improvement in the investment potential of the enterprise by acting on the factors of its formation. The most effective ways to ensure the growth of the investment potential of the enterprise is to provide favorable conditions for the production process at the plant and the removal of bureaucratic and criminal barriers to activ...

  9. Analysis of Factors of Influence of the Market Environment upon Formation of the Enterprise Labour Potential


    Zborovska Olha M.; Halan Olena Ye.


    The article analyses external and internal factors of the market environment, which influence formation of the enterprise labour potential. It offers supplement the existing classification properties with the following ones: international, political-legal and natural-climate factors. It shows that, in the result of the balanced reaction on the international level of influence of factors of formation of labour potential, it is possible to sharply accelerate development of the labour potential ...

  10. SOA Formation Potential of Emissions from Soil and Leaf Litter (United States)

    Faiola, C. L.; Vanderschelden, G. S.; Wen, M.; Cobos, D. R.; Jobson, B. T.; VanReken, T. M.


    In the United States, emissions of volatile organic compounds (VOCs) from natural sources exceed all anthropogenic sources combined. VOCs participate in oxidative chemistry in the atmosphere and impact the concentrations of ozone and particulate material. The formation of secondary organic aerosol (SOA) is particularly complex and is frequently underestimated using state-of-the-art modeling techniques. We present findings that suggest emissions of important SOA precursors from soil and leaf litter are higher than current inventories would suggest, particularly under conditions typical of Fall and Spring. Soil and leaf litter samples were collected at Big Meadow Creek from the University of Idaho Experimental Forest. The dominant tree species in this area of the forest are ponderosa pine, Douglas-fir, and western larch. Samples were transported to the laboratory and housed within a 0.9 cubic meter Teflon dynamic chamber where VOC emissions were continuously monitored with a GC-FID-MS and PTR-MS. Aerosol was generated from soil and leaf litter emissions by pumping the emissions into a 7 cubic meter Teflon aerosol growth chamber where they were oxidized with ozone in the absence of light. The evolution of particle microphysical and chemical characteristics was monitored over the following eight hours. Particle size distribution and chemical composition were measured with a SMPS and HR-ToF-AMS respectively. Monoterpenes dominated the emission profile with emission rates up to 283 micrograms carbon per meter squared per hour. The dominant monoterpenes emitted were beta-pinene, alpha-pinene, and delta-3-carene in descending order. The composition of the SOA produced was similar to biogenic SOA formed from oxidation of ponderosa pine emissions and alpha-pinene. Measured soil/litter monoterpene emission rates were compared with modeled canopy emissions. Results suggest that during fall and spring when tree emissions are lower, monoterpene emissions within forests may be

  11. Elimination of disinfection byproduct formation potential in reclaimed water during solar light irradiation. (United States)

    Qian-Yuan, Wu; Chao, Li; Ye, Du; Wen-Long, Wang; Huang, Huang; Hong-Ying, Hu


    Ecological storage of reclaimed water in ponds and lakes is widely applied in water reuse. During reclaimed water storage, solar light can degrade pollutants and improve water quality. This study investigated the effects of solar light irradiation on the disinfection byproduct formation potential in reclaimed water, including haloacetonitriles (HANs), trichloronitromethane (TCNM), trihalomethanes (THMs), haloketones (HKs) and chloral hydrate (CH). Natural solar light significantly decreased the formation potential of HANs, TCNM, and HKs in reclaimed water, but had a limited effect on the formation potential of THMs and CH. Ultraviolet (UV) light in solar radiation played a dominant role in the decrease of the formation potential of HANs, TCNM and HKs. Among the disinfection byproducts, the removal kinetic constant of dichloroacetonitrile (DCAN) with irradiation dose was much larger than those for dichloropropanone (1,1-DCP), trichloropropanone (1,1,1-TCP) and TCNM. During solar irradiation, fluorescence spectra intensities of reclaimed water also decreased significantly. The removal of tyrosine (Tyr)-like and tryptophan (Trp)-like protein fluorescence spectra intensity volumes was correlated to the decrease in DCAN formation potential. Solar irradiation was demonstrated to degrade Trp, Tyr and their DCAN formation potential. The photolysis products of Trp after solar irradiation were detected as kynurenine and tryptamine, which had chloroform, CH and DCAN formation potential lower than those of Trp.

  12. The preposition potential in formation of conjunctional means

    Directory of Open Access Journals (Sweden)

    Konjuškevič Marija I.


    Full Text Available In the article the ability of preposition to form conjunction or its equivalent has been considered. The mechanism of denominalization has been shown on the Russian material with the involvement of the author’s observations on prepositions in the Belarusian language - the morphological form transformation in to the subordinate part of complex sentence. The author’s conception is: 1 the syntaxeme is the actant position in the sentence; 2 the syntaxeme consists of the formant (preposition + flexion and nominative component (substantive; 3 at the level of the complex sentence the same actant position may take the predicative unit (subordinate part of the complex sentence; 4 the formant of the predicative syntaxeme in transforms is the conjunctional combination “preposition + demonstrative pronoun that + subordinate part conjunction“. The preposition at case syntaxeme transformation in to predicative does not change its function, but it is included in to the conjunctional formant as one of the elements of more complex formant - conjunctional combination. Each element of the conjunctional combination fulfills its function: the preposition still forms the syntaxeme, but with more complex nominative component as predicative unit, the pronoun that is “flection“ of this nominative component (subordinate part, and the conjunction acts as the explicator, providing grammatical connection of the nominative component of syntaxeme with the “flexion“ and the preposition. It is noted that the mechanism and the results of denominalization depend on the syntaxemes repertoire and character and on the preposition meaning: the same preposition, with different meaning has different conjunctional potential. In to the mechanism of denominalization are involved categorematic names (classifiers, which initially are used as structural vocabulary for forming secondary prepositions, and together with them, for forming conjunctional combinations. The methods

  13. Divacancy binding energy, formation energy and surface energy of BCC transition metals using MEAM potentials (United States)

    Uniyal, Shweta; Chand, Manesh; Joshi, Subodh; Semalty, P. D.


    The modified embedded atom method (MEAM) potential parameters have been employed to calculate the unrelaxed divacancy formation energy, binding energy and surface energies for low index planes in bcc transition metals. The calculated results of divacancy binding energy and vacancy formation energy compare well with experimental and other available calculated results.

  14. On the Relationship Between CAI Evolution and Chondrule Formation


    Housley, R M


    The relationship in time and space between CAl formation on the one hand, and chondrule formation on the other is not well understood. It appears that at least compact, coarse-grained CAl were once largely molten. They must have been very depleted in volatiles at that time. However, as now found in Allende they show extensive alteration to volatile rich minerals such as nepheline and sodalite. I have previously argued, partly on the basis of the ubiquitous presence of these vol...

  15. Formation Control of Multirobot Based on I/O Feedback Linearization and Potential Function

    Directory of Open Access Journals (Sweden)

    Jie Dong


    Full Text Available Standard techniques of I/O linearization are widely applied to leader-follower approach for multirobot formation control. However general leader-follower approach cannot adapt to the environment with obstacles. Concerning that issue, a formation control method of multirobot system based on potential function is proposed in this paper, and a new control law is designed by choosing a proper potential function and employing Lyapunov stability theory, which stabilizes the formation of the multirobot system. We combine the method with a leader-follower approach to solve the problem that the latter cannot avoid obstacles. Simulation results are given to validate the method.

  16. Hydrocarbon potential assessment of Ngimbang formation, Rihen field of Northeast Java Basin (United States)

    Pandito, R. H.; Haris, A.; Zainal, R. M.; Riyanto, A.


    The assessment of Ngimbang formation at Rihen field of Northeast Java Basin has been conducted to identify the hydrocarbon potential by analyzing the response of passive seismic on the proven reservoir zone and proposing a tectonic evolution model. In the case of petroleum exploration in Northeast Java basin, the Ngimbang formation cannot be simply overemphasized. East Java Basin has been well known as one of the mature basins producing hydrocarbons in Indonesia. This basin was stratigraphically composed of several formations from the old to the young i.e., the basement, Ngimbang, Kujung, Tuban, Ngerayong, Wonocolo, Kawengan and Lidah formation. All of these formations have proven to become hydrocarbon producer. The Ngrayong formation, which is geologically dominated by channels, has become a production formation. The Kujung formation that has been known with the reef build up has produced more than 102 million barrel of oil. The Ngimbang formation so far has not been comprehensively assessed in term its role as a source rock and a reservoir. In 2013, one exploratory well has been drilled at Ngimbang formation and shown a gas discovery, which is indicated on Drill Stem Test (DST) reading for more than 22 MMSCFD of gas. This discovery opens new prospect in exploring the Ngimbang formation.

  17. Biofilm formation by Listeria monocytogenes on stainless steel surface and biotransfer potential

    Directory of Open Access Journals (Sweden)

    Maíra Maciel Mattos de Oliveira


    Full Text Available An experimental model was proposed to study biofilm formation by Listeria monocytogenes ATCC 19117 on AISI 304 (#4 stainless steel surface and biotransfer potential during this process. In this model, biofilm formation was conducted on the surface of stainless steel coupons, set on a stainless steel base with 4 divisions, each one supporting 21 coupons. Trypic Soy Broth was used as bacterial growth substrate, with incubation at 37 ºC and stirring of 50 rpm. The number of adhered cells was determined after 3, 48, 96, 144, 192 and 240 hours of biofilm formation and biotransfer potential from 96 hours. Stainless steel coupons were submitted to Scanning Electron Microscopy (SEM after 3, 144 and 240 hours. Based on the number of adhered cells and SEM, it was observed that L. monocytogenes adhered rapidly to the stainless steel surface, with mature biofilm being formed after 240 hours. The biotransfer potential of bacterium to substrate occurred at all the stages analyzed. The rapid capacity of adhesion to surface, combined with biotransfer potential throughout the biofilm formation stages, make L. monocytogenes a potential risk to the food industry. Both the experimental model developed and the methodology used were efficient in the study of biofilm formation by L. monocytogenes on stainless steel surface and biotransfer potential.

  18. Removal of disinfection by-product formation potentials by biologically assisted GAC treatment

    Institute of Scientific and Technical Information of China (English)


    The object of this paper is to evaluate the removal of disinfection by-products formation potential by artificially intensified biological activated carbon(BAC) process which is developed on the basis of traditional ozone granular activated carbon (GAC). The results show that 23.1% of trihalomethane formation potential (THMFP) and 68% of haloacetic acid formation potential (HAAFP) can be removed by BAC,respectively. Under the same conditions, the removal rates of the same substances were 12.2% and 13-25 % respectively only by GAC process. Compared with GAC, the high removal rates of the two formed potential substances were due to the increasing of bioactivity of the media and the synergistic capabilities of biological degradation cooperating with activated carbon adsorption of organic compounds. BAC process has some advantages such as long backwashing cycle time, low backwashing intensity and prolonged activated carbon lifetime, etc.

  19. Effect of nepheline syenite particle size on diametrical compression strength and reliability of extruded ceramic Raschig rings used in packed towers

    Directory of Open Access Journals (Sweden)

    Salem, Amin


    Full Text Available In order to understand the effect of nepheline syenite particle size on physico-chemical properties of ceramic Raschig rings, the fluxing agent was grinded at different milling times. The compositions were prepared by blending the illitic-kaolinitic clay and pre-grinded particles. The rings were shaped by a laboratory extruder and then were sintered at 1200 ºC. The mechanical reliability of sintered specimens was mathematically described by Weibull theory and the effect of pre-grinding of fluxing agent on Weibull modulus was evaluated by measuring the diametrical compression strength. Weibull modulus and strength were the criteria for selecting the suitable particle size range of nepheline syenite. It was found that the pre-grinding of nepheline syenite acts as fairly strong parameter on microstructure of rings. The investigation concludes that reliable rings can be fabricated if the particle size of nepheline syenite is arranged between 53 and 75 μm. This enhancement in reliability is valuable in packed towers.Para conocer el efecto del tamaño de partícula de nefelina sienita sobre las propiedades fisicoquímicas de los anillos Raschig cerámicos, este fundente fue molido a diferentes tiempos. Las composiciones se prepararon mediante la mezcla de la arcilla caolinítica illitica y las partículas pre-molidas. Los anillos se obtuvieron en una extrusora de laboratorio y luego fueron sinterizados a 1200 ºC. La fiabilidad mecánica de las muestras sinterizadas se describe matemáticamente por la teoría de Weibull y el efecto de pre-molienda del fundente en el módulo de Weibull se evaluó midiendo la resistencia a la compresión diametral. El módulo de Weibull y la resistencia fueron los criterios para seleccionar el rango de tamaño de partícula adecuado de nefelina sienita para la fabricación de los anillos que se determinó estaba entre 53 y 75 μm comprobándose que influye considerablemente en la microestructura de los mismos. La

  20. Analytic calculation of formation enthalpies directly from interatomic potentials for binary and ternary refractory metal systems

    Institute of Scientific and Technical Information of China (English)


    An analytic method is proposed to calculate the formation enthalpy directly from empirical n-body potential and applied to the binary and ternary systems consisting of the refractory metals Mo, Nb, Ta and W. It turns out that the calculated enthalpies are in overall agreement with experimental observations and some other theoretical calculations. Interestingly, it shows that the formation enthalpies of the ternary systems are significantly affected by those of the constituent binary systems.

  1. Formation of chain structures in systems of charged grains interacting via isotropic pair potentials

    Energy Technology Data Exchange (ETDEWEB)

    Vaulina, O. S.; Lisina, I. I.; Koss, K. G., E-mail: [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation)


    Conditions for the formation of chain structures of charged grains confined in the gravitational field by external electric fields are studied analytically and numerically. The relationships between the parameters of the pair interaction potential, the number of grains, and the electric field gradient in the trap are found. A criterion for the violation of stable equilibrium in a quasi-one-dimensional chain of grains and the formation of a new configuration in the system is proposed.

  2. Hydrocarbon Source Rock Potential of the Sinamar Formation, Muara Bungo, Jambi

    Directory of Open Access Journals (Sweden)

    Moh. Heri Hermiyanto Zajuli


    Full Text Available DOI: 10.17014/ijog.v1i1.175The Oligocene Sinamar Formation consists of shale, claystone, mudstone, sandstone, conglomeratic sandstone, and intercalation of coal seams. The objective of study was to identify the hydrocarbon source rock potential of the Sinamar Formation based on geochemichal characteristics. The analyses were focused on fine sediments of the Sinamar Formation comprising shale, claystone, and mudstone. Primary data collected from the Sinamar Formation well and outcrops were analyzed according to TOC, pyrolisis analysis, and gas chromatography - mass spectometry of normal alkanes that include isoprenoids and sterane. The TOC value indicates a very well category. Based on TOC versus Pyrolysis Yields (PY diagram, the shales of Sinamar Formation are included into oil prone source rock potential with good to excellent categories. Fine sediments of the Sinamar Formation tend to produce oil and gas originated from kerogen types I and III. The shales tend to generate oil than claystone and mudstone and therefore they are included into a potential source rock. 

  3. Formation of image-potential states at the graphene/metal interface


    Armbrust, N.; Güdde, J.; Höfer, U.


    The formation of image-potential states at the interface between a graphene layer and a metal surface is studied by means of model calculations. An analytical one-dimensional model-potential for the combined system is constructed and used to calculate energies and wave functions of the image-potential states at the Gamma-point as a function of the graphene-metal distance. It is demonstrated how the double series of image-potential states of free-standing graphene evolves into interfacial stat...

  4. Stability Analysis and Variational Integrator for Real-Time Formation Based on Potential Field

    Directory of Open Access Journals (Sweden)

    Shengqing Yang


    Full Text Available This paper investigates a framework of real-time formation of autonomous vehicles by using potential field and variational integrator. Real-time formation requires vehicles to have coordinated motion and efficient computation. Interactions described by potential field can meet the former requirement which results in a nonlinear system. Stability analysis of such nonlinear system is difficult. Our methodology of stability analysis is discussed in error dynamic system. Transformation of coordinates from inertial frame to body frame can help the stability analysis focus on the structure instead of particular coordinates. Then, the Jacobian of reduced system can be calculated. It can be proved that the formation is stable at the equilibrium point of error dynamic system with the effect of damping force. For consideration of calculation, variational integrator is introduced. It is equivalent to solving algebraic equations. Forced Euler-Lagrange equation in discrete expression is used to construct a forced variational integrator for vehicles in potential field and obstacle environment. By applying forced variational integrator on computation of vehicles' motion, real-time formation of vehicles in obstacle environment can be implemented. Algorithm based on forced variational integrator is designed for a leader-follower formation.

  5. Analysis of Factors of Influence of the Market Environment upon Formation of the Enterprise Labour Potential

    Directory of Open Access Journals (Sweden)

    Zborovska Olha M.


    Full Text Available The article analyses external and internal factors of the market environment, which influence formation of the enterprise labour potential. It offers supplement the existing classification properties with the following ones: international, political-legal and natural-climate factors. It shows that, in the result of the balanced reaction on the international level of influence of factors of formation of labour potential, it is possible to sharply accelerate development of the labour potential by means of realisation of programmes of international education, legal regulation of migration, active participation in various inter-state projects, etc. Influence of political-legal factors of formation of the labour potential shows up in inter-state agreements on labour migration regulation, in application of the system of uniform branch tariff-qualification reference books and in establishment of the system of licensing individual types of activity. Natural-climate conditions exert significant influence upon the level of labour potential. This influence shows up: in different life expectancies, sickness rate, labour life duration, etc. for various natural-climate zones. The article classifies the factors of labour potential with respect to the enterprise also both by exogenous and endogenous groups.

  6. The Effect of Complex Formation upon the Redox Potentials of Metallic Ions. Cyclic Voltammetry Experiments. (United States)

    Ibanez, Jorge G.; And Others


    Describes experiments in which students prepare in situ soluble complexes of metal ions with different ligands and observe and estimate the change in formal potential that the ion undergoes upon complexation. Discusses student formation and analysis of soluble complexes of two different metal ions with the same ligand. (CW)

  7. Cognitive Association Formation in Episodic Memory: Evidence from Event-Related Potentials (United States)

    Kim, Alice S. N.; Vallesi, Antonino; Picton, Terence W.; Tulving, Endel


    The present study focused on the processes underlying cognitive association formation by investigating subsequent memory effects. Event-related potentials were recorded as participants studied pairs of words, presented one word at a time, for later recall. The findings showed that a frontal-positive late wave (LW), which occurred 1-1.6 s after the…

  8. The Effect of Complex Formation upon the Redox Potentials of Metallic Ions. Cyclic Voltammetry Experiments. (United States)

    Ibanez, Jorge G.; And Others


    Describes experiments in which students prepare in situ soluble complexes of metal ions with different ligands and observe and estimate the change in formal potential that the ion undergoes upon complexation. Discusses student formation and analysis of soluble complexes of two different metal ions with the same ligand. (CW)

  9. Formation kinetics of potential fermentation inhibitors in a steam explosion process of corn straw. (United States)

    Zhang, Yuzhen; Wang, Lan; Chen, Hongzhang


    The weak acids, furan derivatives, and phenolic compounds formed during lignocellulose pretreatment are potential inhibitors of subsequent enzymatic and microbial processes. In this work, the effects of the steam explosion process on the formation of weak acids, furan derivatives, and phenolic compounds were explored. The correlations of different steam explosion conditions and formation kinetics of degradation products showed that the formation of weak acids and furan derivatives was in the first-order reactions, which are expressed as [Formula: see text]. The formation of weak acids and furan derivatives increases with pretreatment temperature and time. On the other hand, the formation of phenolic compounds showed typical characteristics of continuous reaction, expressed as [Formula: see text]. The formation was affected by the active energies in two stages, temperature and time, and thus existed at extreme value. This work revealed the formation rules of weak acids, furan derivatives, and phenolic compounds in a steam explosion process and provided theoretical guidelines for improving the process and limiting the production of certain inhibitors.

  10. Double Layers: Potential Formation and Related Nonlinear Phenomena in Plasmas: Proceedings of the 5th Symposium (United States)

    Iizuka, S.


    The Table of Contents for the book is as follows: * PREFACE * INTERNATIONAL SCIENTIFIC COMMITTEE * LOCAL ORGANIZING COMMITTEE AT TOHOKU UNIVERSITY * CHAPTER 1: DOUBLE LAYERS, SHEATHS, AND POTENTIAL STRUCTURES * 1.1 Double Layers * On Fluid Models of Stationary, Acoustic Double Layers (Invited) * Particle Simulation of Double Layer (Invited) * Space-Time Dependence of Non-Steady Double Layers * The Role of Low Energy Electrons for the Generation of Anode Double Layers in Glow Discharges * Arbitrary Amplitude Ion-Acoustic Double Layers in a Dusty Plasma * 1.2 Sheaths * Bounded Plasma Edge Physics as Observed from Simulations in 1D and 2D (Invited) * Control of RF Sheath Structure in RF Diode Discharge * Observation of Density Gradients with Fine Structures and Low Frequency Wave Excitation at the Plasma-Sheath Boundary * Double Sheath Associated with an Electron Emission to a Plasma Containing Negative Ions * Sheath Edge and Floating Potential for Multi-Species Plasmas Including Dust Particles * 1.3 Potential Structures and Oscillations * Potential Structure Formed at a Constriction of a DC He Positive Column and its Coupling with Ionization Wave * Potential Structure in a New RF Magnetron Device with a Hollow Electrode * Potential Disruption in a RF Afterglow Electronegative Plasma * Potential Oscillation in a Strongly Asymmetry RF Discharge Containing Negative Ions * Effects of External Potential Control on Coulomb Dust Behavior * Potential Structure of Carbon Arc Discharge for High-Yield Fullerenes Formation * Control of Axial and Radial Potential Profiles in Tandem Mirrors (Invited) * CHAPTER 2: FIELD-ALIGNED ELECTRIC FIELDS AND RELATED PARTICLE ACCELERATIONS * 2.1 Field-Aligned Potential Formation * Formation of Large Potential Difference in a Plasma Flow along Converging Magnetic Field Lines (Invited) * Presheath Formation in front of an Oblique End-Plate in a Magnetized Sheet Plasma * Plasma Potential Formation Due to ECRH in a Magnetic Well * Electrostatic

  11. Factors of Formation of the tax Potential of the Securities Market

    Directory of Open Access Journals (Sweden)

    Gumenniy Anatoliy A.


    Full Text Available The article is devoted to the problems of identification of factors that influence volumes and dynamics of the tax potential of the securities market. The goal of the article is detection and systematisation of factors of formation and realisation of the tax potential of the securities market. In the result of the conducted study it systemises factors of formation and realisation of the tax potential of the securities market by two groups: economic and legislatory organisational. The main of the economic factors are: state of economic development, degree of the shadow economy, level of savings of the population, level of trust of the population and level of inflation. The article justifies interconnection that exist between the said factors and volumes of the tax potential of the securities market. In particular, it proves that increase of volumes of the shadow economy facilitates reduction of the tax potential of the securities market, since it facilitates outflow of capital from the official sector of economy. Growth of unorganised savings of the population, the volume of which grows proportionally to the growth of the level of distrust of the population to the securities market, has a negative impact on formation of the tax potential of the securities market. Degree of the negative impact of the said factors grows in the event of deterioration of the state of the macro-economic situation and growth of inflation. The legislatory organisational factors are: object, base, rates of taxation of securities trading and the securities market infrastructure. The article proves that low level of infrastructure development could significantly reduce the tax potential of the securities market. The proposed approach to the study of factors of formation of the tax potential gives a possibility to mark out, apart from de-shadowing of operations and expansion of the taxation base, one more direction on increase of the tax potential of the securities market

  12. A multi-level strategy for anticipating future glacier lake formation and associated hazard potentials (United States)

    Frey, Holger; Haeberli, Wilfried; Huggel, Christian; Linsbauer, Andreas


    Due to the expected atmospheric warming, mountain glaciers will retreat, potentially collapse or even vanish completely during the 21st century. When overdeepened parts of the glacier bed are exposed in the course of glacier retreat, glacier lakes can form. Such lakes have a potential for hydropower production, which is an important source of renewable energy. Furthermore they are important elements in the perception of high-mountain landscapes and they can compensate the loss of landscape attractiveness from glacier shrinkage to a certain degree. However, glacier lakes are also a potential source of serious flood and debris flow hazards, especially in densely populated mountain ranges. Thus, methods for early detection of sites with potential lake formation are important for early planning and development of protection concepts. In this contribution we present a multi-scale approach to detect sites with potential future lake formation on four different levels of detail. The methods are developed, tested and - as far as possible - verified in the Swiss Alps; but they can be applied to mountain regions all over the world. On a first level, potential overdeepenings are estimated by selecting flat parts (slope routing models. Finally, for potentially critical or dangerous situations, on-site geophysical measurements such as ground penetrating radar applied on different sections of a glacier can be performed on the fourth level to investigate the overdeepenings in more detail. These methods are verified based on historical data from the Trift glacier in the Bernese Alps, where a lake formed in front of the glacier since the 1990s up to the present. Potential future lake scenarios are presented for two regions in the Swiss Alps and the outburst potential of such future lakes is investigated for the Bernina region. The proposed method is an important step towards early detection of new potential flood hazards related to rapid glacier retreat. At the same time, it can

  13. Trihalomethane formation potential of shrimp farm effluents in Chachoengsao Province, Thailand

    Directory of Open Access Journals (Sweden)

    Aweewan Mangmeechai


    Full Text Available Shrimp farm effluents along Bangpakong River in Chachoengsao Province, Thailand, were evaluated for their trihalomethane formation potential (THMFP, which were shown to be in the range of 810-3,100 µg/L. Samples from river locations, both upstream and downstream from these selected farms, were also tested for their existing THMFP. These river samples were illustrated to have notably lower level of THMFP than the shrimp farm effluents. The downstream concentration was, however, found to be significantly higher than the upstream (as much as 5 times. This indicated that the contamination of shrimp farm effluents could have increased the formation potential of THMs in the natural water source. The experimental results showed a positive correlation between salinity and THMFP. The formation of various THM species depended significantly on the level of salinity in the water sample. Low salinity (0-5 ppt often led to a high formation of chloroform and bromodichloromethane while high salinity (5-15 ppt resulted in a great quantity of dibromochloromethane and bromoform. FTIR spectra of the samples before and after chlorination suggested that the functional groups involved in the reaction were hydroxyl group, amines group, aromatic ring, aliphatic chloro compounds and aliphatic bromo compounds, whereas C-O was the product from the reaction.

  14. Precipitate Formation Potential of Resin Regeneration Effluent in the 100-HR-3 Operable Unit

    Energy Technology Data Exchange (ETDEWEB)

    Cantrell, Kirk J.


    Calculations performed as part of this study indicate that injection of treated groundwater containing treated regenerant solution has a high potential for precipitate formation that could lead to plugging of formation porosity surrounding the injection well. In the worst case scenario, substantial plugging could occur within a year of the initiation of injection. Some uncertainty is associated with respect to this conclusion. The uncertainty results from the fact that equilibrium with the most stable mineral assemblage cannot always be assumed and that slow precipitation rates could occur and reliable estimates of precipitation kinetics under Hanford aquifer conditions are not available. It is recommended that the potential of calcium phosphate precipitation be investigated further using a combination of laboratory and field investigations.

  15. Sphygmomanometers and thermometers as potential fomites of Staphylococcus haemolyticus: biofilm formation in the presence of antibiotics (United States)

    Sued, Bruna Pinto Ribeiro; Pereira, Paula Marcele Afonso; Faria, Yuri Vieira; Ramos, Juliana Nunes; Binatti, Vanessa Batista; dos Santos, Kátia Regina Netto; Seabra, Sérgio Henrique; Hirata, Raphael; Vieira, Verônica Viana; Mattos-Guaraldi, Ana Luíza; Pereira, José Augusto Adler


    BACKGROUND The association between Staphylococcus haemolyticus and severe nosocomial infections is increasing. However, the extent to which fomites contribute to the dissemination of this pathogen through patients and hospital wards remains unknown. OBJECTIVES In the present study, sphygmomanometers and thermometers were evaluated as potential fomites of oxacillin-resistant S. haemolyticus (ORSH). The influence of oxacillin and vancomycin on biofilm formation by ORSH strains isolated from fomites was also investigated. METHODS The presence of ORSH on swabs taken from fomite surfaces in a Brazilian hospital was assessed using standard microbiological procedures. Antibiotic susceptibility profiles were determined by the disk diffusion method, and clonal distribution was assessed in pulsed-field gel electrophoresis (PFGE) assays. Minimum inhibitory concentrations (MICs) of oxacillin and vancomycin were evaluated via the broth microdilution method. Polymerase chain reaction (PCR) assays were performed to detect the mecA and icaAD genes. ORSH strains grown in media containing 1/4 MIC of vancomycin or oxacillin were investigated for slime production and biofilm formation on glass, polystyrene and polyurethane catheter surfaces. FINDINGS ORSH strains comprising five distinct PFGE types were isolated from sphygmomanometers (n = 5) and a thermometer (n = 1) used in intensive care units and surgical wards. ORSH strains isolated from fomites showed susceptibility to only linezolid and vancomycin and were characterised as multi-drug resistant (MDR). Slime production, biofilm formation and the survival of sessile bacteria differed and were independent of the presence of the icaAD and mecA genes, PFGE type and subtype. Vancomycin and oxacillin did not inhibit biofilm formation by vancomycin-susceptible ORSH strains on abiotic surfaces, including on the catheter surface. Enhanced biofilm formation was observed in some situations. Moreover, a sub-lethal dose of vancomycin induced

  16. Evidence of syn tectonic tephrites with nepheline in the Sidi Said Maachou Cambrian basin (coastal Meseta, Morocco); geo dynamic implications; Mise en evidence de tephrites a nepheline syntectoniques dans le bassin cambrien de Sidi Said Maachou (Meseta cotiere, Maroc); signification geodynamique

    Energy Technology Data Exchange (ETDEWEB)

    Remmal, T.; Mohsine, A.; El Hatimi, N.


    Based on a combined structural, petrographic, and geochemical analysis, a new interpretation of the basic magmatism of Sidi Said Maachou (coastal Meseta) in two stages of emplacement is proposed. The first stage is characterized by transitional pyroclastic flows that have accompanied the opening of the West-Mesetian basin, during the Cambrian; the second stage is made of dykes of basalts, dolerites, and tephrites bearing nepheline. The emplacement of this undersaturated alkaline magma is associated to a sinistral sub meridian shear zone which has been activated at the end of the Caledonian orogenesis, by a mantellic advection. (Author) 32 refs.

  17. Tsunami characteristics and formation potential of sandy tsunami deposit in Sanriku Coast: implications from numerical modeling (United States)

    Sugawara, D.; Haraguchi, T.; Takahashi, T.


    Geological investigation of paleotsunami deposit is crucial for knowing the history and magnitude of tsunami events in the past. Among various kinds of grain sizes, sandy tsunami deposit has been best investigated by previous studies, because of its potential for identification in the sedimentary column. Many sandy tsunami deposits have been found from coastal plains, which have sandy beach and low-lying wetlands. However, sandy tsunami deposits in narrow valleys at rocky ria coast have rarely been found. It may be presumed that formation potential of sandy tsunami layer in the rocky coasts is generally lower than coastal plains, because of the absence of sandy beach, tsunami run-up on steeper slope and stronger return flow. In this presentation, characteristics of the 2011 Tohoku-oki earthquake tsunami in Sanriku Coast, a continuous rocky ria coast located in the northeast Japan, is investigated based on numerical modeling. In addition, the formation potential of sandy tsunami deposit is also investigated based on numerical modeling of sediment transport. Preliminary result of tsunami hydrodynamics showed that the waveform and amplification of the tsunami are clearly affected by the local bathymetry, which is associated with submerged topography formed during the last glacial stage. Although the tsunami height in the offshore of each bay is around 8.0 m, the tsunami height at the bay head was increased in different way. The amplification factor at the bay head was typically 2.0 among most of V-shaped narrow embayments; meanwhile the amplification factor is much lower than 1.0 at some cases. The preliminary result of the modeling of sediment transport predicted huge amount of sediments may be suspended into the water column, given that sandy deposit is available there. Massive erosion and deposition of sea bottom sediments may commonly take place in the bays. However, formation of onshore tsunami deposit differs from each other. Whether the suspended sediments

  18. The formation and development of innovative potential of the company’s employees

    Directory of Open Access Journals (Sweden)

    E. A. Kipervar


    Full Text Available Modern economic development is possible on the basis of increase of efficiency of activity of enterprises, which is based on the rational use of the labor potential of employees. The current research is formulated and enriched the concept of labor potential, but there are still many unresolved theoretical and methodologically aspects related to the study of labor potential and its components, as they arise in connection with changes in the economy, the modern requirements to enterprises in the period of their innovative development. Innovative activities of enterprises should be based on the use of highly skilled, highly intelligent, high-performance staff able to generate, develop, apply new ideas, technologies and products. The requirements of the environment to stimulate enterprise in the formation of personnel, concerned in the results of the enterprise, upbeat and generating innovation. Particular attention should be given to the formation and development of innovative potential of employees as part of the labor potential, its planning, that will be reflected in improving the efficiency of the personnel and the efficiency of enterprises. It is necessary to further develop approaches to the formation and development of the capacity of workers in relation to the innovation component of labor potential, aimed at improving the competitiveness of enterprises. Results of the research outlined in this paper are aimed at deepening and broadening of theoretical bases in this area. The authors of the necessity of innovative development based on employee motivation structure and the level of their claims, professional, intellectual level, as well as realize their innovative potential. The necessity of its correction and give you strength-of planning in the direction of determining acceptable and normative values of the innovative potential of each category of workers, determination of deviations of actual values from the standard followed by the

  19. Development and functioning of microorganisms in concentration cycles of sulfide copper-nickel and non-sulfide apatite-nepheline ores

    Directory of Open Access Journals (Sweden)

    Fokina N. V.


    Full Text Available The number and trophic diversity of bacteria in flotation samples of apatite-nepheline and sulfide copper-nickel ores at the concentration plants of JSC "Apatite" and Kola Mining and Metallurgical Company have been determined. The study of the size and diversity of the microbiota has been conducted by culture on selective nutrient media. The total number and biomass of bacteria have been considered by fluorescence microscopy using Cyclopore polycarbonate membrane filters. Bacteria have been identified by molecular genetic methods. The least amount of both saprotrophic and other trophic groups of bacteria has been observed in the samples of ore and recycled water as at the concentrating factory of Apatit JSC, and also at the plant "Pechenganikel". It has been found out that the bacteria contained in the ore and recycling water flowing from the tailings increased their number during the flotation process due to coming of the nutrients with the flotation reagents, aeration and increased temperature. Strains which occurrence is more than 60 % have been extracted from recycled water and basic flotation products and classified as Pseudomonas. Two strains with occurrence of more than 60 % have been discovered at Apatit JSC and classified as Stenotrophomonas and Acinetobacter. The number of fungi in the cycle of apatite-nepheline ore enrichment at the factories is very low (1 to 24 CFU / 1 ml or 1 g of ore. Fungi of the genus Penicillium have been dominated, fungi of the genera Acremonium, Aureobasidium, Alternaria, Chaetomium have also been detected. At the plant "Pechenganikel" species Aspergillus fumigatus, Penicillium aurantiogriseum and P. glabrum have been extracted. It has been shown that the bacteria deteriorate the apatite flotation as a result of their interaction with active centers of calcium-containing minerals and intensive flocculation decreasing the floatation selectivity. Also some trend of copper and nickel recovery change has been

  20. Ethyl Formate: A Potential Disinfestation Treatment for Eucalyptus Weevil (Gonipterus platensis) (Coleoptera: Curculionidae) in Apples. (United States)

    Agarwal, Manjree; Ren, Yonglin; Newman, James; Learmonth, Stewart


    Export of Pink Lady apples from Australia has been significantly affected by infestations of adult eucalyptus weevils (Gonipterus platensis Marelli). These weevils cling tenaciously to the pedicel of apple fruit when selecting overwintering sites. As a result, apples infested with live G. platensis adults lead to rejection for export. Since the Montreal Protocol restricted use of methyl bromide as postharvest treatment, it was necessary to consider alternative safer fumigants for disinfestation of eucalyptus weevil. Laboratory experiments were conducted using concentrations of 5, 10, 15, 20, 25, 30, 40, and 80 mg/liter of ethyl formate. Complete control (100% mortality) was achieved at 25-30 mg/liter of ethyl formate at 22-24°C for 24-h exposure without apples. However, with 90-95% of the volume full of apples, complete control was achieved at 40 mg/liter of ethyl formate at 22-24°C for 24-h exposure. No phytotoxicity was observed and after one day aeration, residue of ethyl formate declined to natural levels (0.05-0.2 mg/kg). Five ethyl formate field trials were conducted in cool storages (capacity from 250-900 tons) and 100% kill of eucalyptus weevils were achieved at 50-55 mg/liter at 7-10°C for 24 h. Ethyl formate has great potential for preshipment treatment of apples. Its use is considerably cheaper and safer than already existing fumigants like methyl bromide and phosphine.

  1. Field measurements of the ambient ozone formation potential in Beijing during winter (United States)

    Crilley, Leigh; Kramer, Louisa; Thomson, Steven; Lee, James; Squires, Freya; Bloss, William


    The air quality issues in Beijing have been well-documented, and the severe air pollution levels result in a unique chemical mix in the urban boundary layer, both in terms of concentration and composition. As many of the atmospheric chemical process are non-linear and interlinked, this makes predictions difficult for species formed in atmosphere, such as ozone, requiring field measurements to understand these processes in order to guide mitigation efforts. To investigate the ozone formation potential of ambient air, we employed a custom built instrument to measure in near real time the potential for in situ ozone production, using an artificial light source. Our results are thus indicative of the ozone formation potential for the sampled ambient air mixture. Measurements were performed as part of the Air Pollution and Human Health (APHH) field campaign in November / December 2016 at a suburban site in central Beijing. We also conducted experiments to examine the ozone production sensitivity to NOx. We will present preliminarily results from ambient sampling and NOx experiments demonstrating changes in the ozone production potential during clean and haze periods in Beijing.

  2. Chemical reactivity and skin sensitization potential for benzaldehydes: can Schiff base formation explain everything? (United States)

    Natsch, Andreas; Gfeller, Hans; Haupt, Tina; Brunner, Gerhard


    Skin sensitizers chemically modify skin proteins rendering them immunogenic. Sensitizing chemicals have been divided into applicability domains according to their suspected reaction mechanism. The widely accepted Schiff base applicability domain covers aldehydes and ketones, and detailed structure-activity-modeling for this chemical group was presented. While Schiff base formation is the obvious reaction pathway for these chemicals, the in silico work was followed up by limited experimental work. It remains unclear whether hydrolytically labile Schiff bases can form sufficiently stable epitopes to trigger an immune response in the living organism with an excess of water being present. Here, we performed experimental studies on benzaldehydes of highly differing skin sensitization potential. Schiff base formation toward butylamine was evaluated in acetonitrile, and a detailed SAR study is presented. o-Hydroxybenzaldehydes such as salicylaldehyde and the oakmoss allergens atranol and chloratranol have a high propensity to form Schiff bases. The reactivity is highly reduced in p-hydroxy benzaldehydes such as the nonsensitizing vanillin with an intermediate reactivity for p-alkyl and p-methoxy-benzaldehydes. The work was followed up under more physiological conditions in the peptide reactivity assay with a lysine-containing heptapeptide. Under these conditions, Schiff base formation was only observable for the strong sensitizers atranol and chloratranol and for salicylaldehyde. Trapping experiments with NaBH₃CN showed that Schiff base formation occurred under these conditions also for some less sensitizing aldehydes, but the reaction is not favored in the absence of in situ reduction. Surprisingly, the Schiff bases of some weaker sensitizers apparently may react further to form stable peptide adducts. These were identified as the amides between the lysine residues and the corresponding acids. Adduct formation was paralleled by oxidative deamination of the parent

  3. Bioanalytical and chemical assessment of the disinfection by-product formation potential: role of organic matter. (United States)

    Farré, Maria José; Day, Sophie; Neale, Peta A; Stalter, Daniel; Tang, Janet Y M; Escher, Beate I


    Disinfection by-products (DBP) formed from natural organic matter and disinfectants like chlorine and chloramine may cause adverse health effects. Here, we evaluate how the quantity and quality of natural organic matter and other precursors influence the formation of DBPs during chlorination and chloramination using a comprehensive approach including chemical analysis of regulated and emerging DBPs, total organic halogen quantification, organic matter characterisation and bioanalytical tools. In vitro bioassays allow us to assess the hazard potential of DBPs early in the chain of cellular events, when the DBPs react with their molecular target(s) and activate stress response and defence mechanisms. Given the reactive properties of known DBPs, a suite of bioassays targeting reactive modes of toxic action including genotoxicity and sensitive early warning endpoints such as protein damage and oxidative stress were evaluated in addition to cytotoxicity. Coagulated surface water was collected from three different drinking water treatment plants, along with reverse osmosis permeate from a desalination plant, and DBP formation potential was assessed after chlorination and chloramination. While effects were low or below the limit of detection before disinfection, the observed effects and DBP levels increased after disinfection and were generally higher after chlorination than after chloramination, indicating that chlorination forms higher concentrations of DBPs or more potent DBPs in the studied waters. Bacterial cytotoxicity, assessed using the bioluminescence inhibition assay, and induction of the oxidative stress response were the most sensitive endpoints, followed by genotoxicity. Source waters with higher dissolved organic carbon levels induced increased DBP formation and caused greater effects in the endpoints related to DNA damage repair, glutathione conjugation/protein damage and the Nrf2 oxidative stress response pathway after disinfection. Fractionation studies

  4. Use of simulated evaporation to assess the potential for scale formation during reverse osmosis desalination (United States)

    Huff, G.F.


    The tendency of solutes in input water to precipitate efficiency lowering scale deposits on the membranes of reverse osmosis (RO) desalination systems is an important factor in determining the suitability of input water for desalination. Simulated input water evaporation can be used as a technique to quantitatively assess the potential for scale formation in RO desalination systems. The technique was demonstrated by simulating the increase in solute concentrations required to form calcite, gypsum, and amorphous silica scales at 25??C and 40??C from 23 desalination input waters taken from the literature. Simulation results could be used to quantitatively assess the potential of a given input water to form scale or to compare the potential of a number of input waters to form scale during RO desalination. Simulated evaporation of input waters cannot accurately predict the conditions under which scale will form owing to the effects of potentially stable supersaturated solutions, solution velocity, and residence time inside RO systems. However, the simulated scale-forming potential of proposed input waters could be compared with the simulated scale-forming potentials and actual scale-forming properties of input waters having documented operational histories in RO systems. This may provide a technique to estimate the actual performance and suitability of proposed input waters during RO.

  5. Radiative bound-state-formation cross-sections for dark matter interacting via a Yukawa potential

    CERN Document Server

    Petraki, Kalliopi; de Vries, Jordy


    We calculate the cross-sections for the radiative formation of bound states by dark matter whose interactions are described in the non-relativistic regime by a Yukawa potential. These cross-sections are important for cosmological and phenomenological studies of dark matter with long-range interactions, residing in a hidden sector, as well as for TeV-scale WIMP dark matter. We provide the leading-order contributions to the cross-sections for the dominant capture processes occurring via emission of a vector or a scalar boson. We offer a detailed inspection of their features, including their velocity dependence within and outside the Coulomb regime, and their resonance structure. For pairs of annihilating particles, we compare bound-state formation with annihilation.

  6. A Cultural Psychological Approach to Analyze Intercultural Learning: Potential and Limits of the Structure Formation Technique

    Directory of Open Access Journals (Sweden)

    Doris Weidemann


    Full Text Available Despite the huge interest in sojourner adjustment, there is still a lack of qualitative as well as of longitudinal research that would offer more detailed insights into intercultural learning processes during overseas stays. The present study aims to partly fill that gap by documenting changes in knowledge structures and general living experiences of fifteen German sojourners in Taiwan in a longitudinal, cultural-psychological study. As part of a multimethod design a structure formation technique was used to document subjective theories on giving/losing face and their changes over time. In a second step results from this study are compared to knowledge-structures of seven long-term German residents in Taiwan, and implications for the conceptualization of intercultural learning will be proposed. Finally, results from both studies serve to discuss the potential and limits of structure formation techniques in the field of intercultural communication research. URN: urn:nbn:de:0114-fqs0901435

  7. Ambient new particle formation parameter indicates potential rise in future events

    Directory of Open Access Journals (Sweden)

    B. Bonn


    Full Text Available Atmospheric new particle formation is a general phenomenon observed over coniferous forests. So far nucleation is described as a function of gaseous sulfuric acid concentration only, which is unable to explain the observed seasonality of nucleation events at different measurement sites. Here we introduce a new nucleation parameter including ozone and water vapor concentrations as well as UV-B radiation as a proxy for OH radical formation. Applying this new parameter to field studies conducted at Finnish and German measurement sites it is found capable to predict the occurrence of nucleation events and their seasonal and annual variation indicating a significant role of organics. Extrapolation to possible future conditions of ozone, water vapor and organic concentrations leads to a significant potential increase in nucleation event number.

  8. Investigation into the oxidative potential generated by the formation of particulate matter from incense combustion. (United States)

    Chuang, Hsiao-Chi; BéruBé, Kelly; Lung, Shih-Chun C; Bai, Kuan-Jen; Jones, Tim


    The formation of aerosols during combustion plays an important role in allowing released products to interreact, leading to an increase in particulate matter oxidative potential. This study investigated the physicochemistry of incense combustion-derived pollutants, which were emitted into the ambient air as solid and gas phases, followed by the determination of their oxidative potential. Upon combustion of a joss stick, approximately 60% of the mass of incense raw ingredients was released into the ambient air as combustion products including 349.51 mg/g PM(10), 145.48 mg/g CO and 0.16 mg/g NOx. Furthermore, incense combustion produced significant number of primary particles (incense combustion was able to react with CaCO(3) to produce the final product of Ca(NO(3))(2) in the ambient air. Moreover, coagulation could be a vital process for the growth of primary incense combustion particles through the intermixing with volatile organics. The incense particle's reactions with other combustion-derived products could be responsible for their significant oxidative capacity of 33.1-43.4% oxidative DNA damage. This study demonstrated that the oxidative potential of incense particles appeared to be related to the process of particle formation, and also provided novel data for the respiratory exposure assessment.

  9. Effects of applied potential on phosphine formation in synthetic wastewater treatment by Microbial Electrolysis Cell (MEC). (United States)

    Liu, Wei; Niu, Xiaojun; Chen, Weiyi; An, Shaorong; Sheng, Hong


    Phosphine (PH3) emission from conventional biological wastewater treatment is very inefficient (ng-μg m(-3)). In this work, we investigated the feasibility of promoting PH3 formation from inorganic phosphorus (IP) or organic phosphorus (OP) containing synthetic wastewater treatment by Microbial Electrolysis Cell (MEC) for the first time. Positive effect of applied potential on PH3 production was observed after methanogens was inhibited. The highest production of PH3 (1103.10 ± 72.02 ng m(-3)) was obtained in IP-fed MEC operated at -0.6 V, which was about 5-fold and 2-fold compared to that in open circuit experiment and OP-fed MEC, respectively. Meanwhile, PH3 formation corresponded positively with current density and alkaline phosphatase activity. This result showed that suitable potential could enhance the activity of relevant enzymes and boost the biosynthesis of PH3. Bacterial communities analysis based on high-throughput sequencing revealed that applied potential was conductive to the enrichment of phosphate-reducing organisms in contrast to the control test. These results provide a new idea for resource utilization of phosphorus in wastewater. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. On assessing the gas formation potential of renewable primary products; Zur Bewertung des Gasbildungspotenzials von nachwachsenden Rohstoffen

    Energy Technology Data Exchange (ETDEWEB)

    Weissbach, Friedrich


    Biogas production depends on the gas formation potential of the substrates used and to what extent that potential is exploited by fermentation technology. The focus of substrate assessment can only be its gas formation potential, independent of fermentation technology. To calculate the gas formation potential of harvested crops and the silages produced from them a new parameter is proposed, which is the ''content of fermentable organic matter'' (FOM). This parameter can be computed from the results of relatively simple laboratory analyses. Equations for estimation are proposed, which were derived from a large number of digestion experiments with sheep. (orig.)

  11. Potential Sources and Formations of the PM2.5 Pollution in Urban Hangzhou

    Directory of Open Access Journals (Sweden)

    Jian Wu


    Full Text Available Continuous measurements of meteorological parameters, gaseous pollutants, particulate matters, and the major chemical species in PM2.5 were conducted in urban Hangzhou from 1 September to 30 November 2013 to study the potential sources and formations of PM2.5 pollution. The average PM2.5 concentration was 69 µg·m−3, ~97% higher than the annual concentration limit in the national ambient air quality standards (NAAQS of China. Relative humidity (RH and wind speed (WS were two important factors responsible for the increase of PM2.5 concentration, with the highest value observed under RH of 70%–90%. PM2.5 was in good correlation with both NO2 and CO, but not with SO2, and the potential source contribution function (PSCF results displayed that local emissions were important potential sources contributing to the elevated PM2.5 and NO2 in Hangzhou. Thus, local vehicle emission was suggested as a major contribution to the PM2.5 pollution. Concentrations of NO2 and CO significantly increased in pollution episodes, while the SO2 concentration even decreased, implying local emission rather than region transport was the major source contributing to the formation of pollution episodes. The sum of SO42−, NO3−, and NH4+ accounted for ~50% of PM2.5 in mass in pollution episodes and the NO3−/EC ratios were significantly elevated, revealing that the formation of secondary inorganic species, particularly NO3−, was an important contributor to the PM2.5 pollution in Hangzhou. This study highlights that controlling local pollution emissions was essential to reduce the PM2.5 pollution in Hangzhou, and the control of vehicle emission in particular should be further promoted in the future.

  12. Potential for deep basin-centered gas accumulation in Travis Peak (Hosston) Formation, Gulf Coastal Basin (United States)

    Bartberger, Charles E.; Dyman, Thaddeus S.; Condon, Steven M.


    The potential of Lower Cretaceous sandstones of the Travis Peak Formation in the northern Gulf Coast Basin to harbor a basin-centered gas accumulation was evaluated by examining (1) the depositional and diagenetic history and reservoir properties of Travis Peak sandstones, (2) the presence and quality of source rocks for generating gas, (3) the burial and thermal history of source rocks and time of gas generation and migration relative to tectonic development of Travis Peak traps, (4) gas and water recoveries from drill-stem and formation tests, (5) the distribution of abnormal pressures based on shut-in-pressure data, and (6) the presence or absence of gas-water contacts associated with gas accumulations in Travis Peak sandstones. The Travis Peak Formation (and correlative Hosston Formation) is a basinward-thickening wedge of terrigenous clastic sedimentary rocks that underlies the northern Gulf Coast Basin from eastern Texas across northern Louisiana to southern Mississippi. Clastic infl ux was focused in two main fl uvial-deltaic depocenters?one located in northeastern Texas and the other in southeastern Mississippi and northeastern Louisiana. Across the main hydrocarbon-productive trend in eastern Texas and northern Louisiana, the Travis Peak Formation is about 2,000 ft thick. Most Travis Peak hydrocarbon production in eastern Texas comes from drilling depths between 6,000 and 10,000 ft. Signifi cant decrease in porosity and permeability occurs through that depth interval. Above 8,000-ft drilling depth in eastern Texas, Travis Peak sandstone matrix permeabilities often are signifi cantly higher than the 0.1-millidarcy (mD) cutoff that characterizes tight-gas reservoirs. Below 8,000 ft, matrix permeability of Travis Peak sandstones is low because of pervasive quartz cementation, but abundant natural fractures impart signifi cant fracture permeability. Although pressure data within the middle and lower Travis Peak Formation are limited in eastern Texas

  13. Educational and Professional Potential of Personnel: Essence and Role in Formation of Investment Attractiveness of a Company


    Skrynkovskyy Ruslan M.


    The article reveals the essence of educational and professional potential of personnel and investment attractiveness of a company. It provides a model of formation of investment attractiveness of a company. It establishes the role of educational and professional potential of personnel in formation of investment attractiveness of a company. It provides a mathematical description of influence of educational and professional potential of personnel on investment attractiveness of a company.В стат...

  14. Electron transfer and biofilm formation of Shewanella putrefaciens as function of anode potential. (United States)

    Carmona-Martínez, Alessandro A; Harnisch, Falk; Kuhlicke, Ute; Neu, Thomas R; Schröder, Uwe


    Shewanellaceae are among the most widely studied electroactive microorganisms. In this report, we studied the influence of the applied electrode potential on the anodic current production of Shewanella putrefaciens NCTC 10695 under anoxic conditions. Furthermore, we used cyclic voltammetry (CV) and confocal laser scanning microscopy (CLSM) to investigate the microbial electron transfer and biofilm formation. It is shown that the chronoamperometric current density is increasing with increasing electrode potential from 3 μA cm(-2) at -0.1 V up to -12 μA cm(-2) at +0.4 V (vs. Ag/AgCl), which is accompanied by an increasing amount of biomass deposited on the electrode. By means of cyclic voltammetry we demonstrate that direct electron transfer (DET) is dominating and the planktonic cells play only a minor role. 2012 Elsevier B.V. All rights reserved

  15. Formation of Non-Monotonic Potential Structure in the Detached Plasma (United States)

    Ishiguro, Seiji; Pianpanit, Theerasarn; Hasegawa, Hiroki


    Plasma detachment has been investigated by means of PIC simulation which includes plasma-neutral collision and Coulomb collision. In our previous study, we have shown that a strong gradient in temperature appears in front of the target plate in the case that high density and low temperature neutral gas is introduced. It is observed that a potential hill is created in the neutral gas region where ions lose energy due to the elastic and charge exchange collision and, as a result, the ion density increases. This potential structure traps the low energy electrons and may play a role in the development of plasma detachment state. This work is supported by NIFS Collaboration Research Programs NIFS14KNXN279 and NIFS14KNSS059 and the NIFS/NINS project of Formation of International Scientific Base and Network.

  16. Coherent molecule formation in anharmonic potentials near confinement-induced resonances. (United States)

    Sala, S; Zürn, G; Lompe, T; Wenz, A N; Murmann, S; Serwane, F; Jochim, S; Saenz, A


    We perform a theoretical and experimental study of a system of two ultracold atoms with tunable interaction in an elongated trapping potential. We show that the coupling of center-of-mass and relative motion due to an anharmonicity of the trapping potential leads to a coherent coupling of a state of an unbound atom pair and a molecule with a center of mass excitation. By performing the experiment with exactly two particles we exclude three-body losses and can therefore directly observe coherent molecule formation. We find quantitative agreement between our theory of inelastic confinement-induced resonances and the experimental results. This shows that the effects of center-of-mass to relative-motion coupling can have a significant impact on the physics of quantum systems near center-of-mass to relative-motion coupling resonances.

  17. Biological Communities in Desert Varnish and Potential Implications for Varnish Formation Mechanisms (United States)

    Lang-Yona, Naama; Maier, Stefanie; Macholdt, Dorothea; Rodriguez-Caballero, Emilio; Müller-Germann, Isabell; Yordanova, Petya; Jochum, Klaus-Peter; Andreae, Meinrat O.; Pöschl, Ulrich; Weber, Bettina; Fröhlich-Nowoisky, Janine


    Desert varnishes are thin, orange to black coatings found on rocks in arid and semi-arid environments on Earth. The formation mechanisms of rock varnish are still under debate and the involvement of microorganisms in this process remains unclear. In this work we aimed to identify the microbial community occurring in rock varnish to potentially gain insights into the varnish formation mechanism. For this purpose, rocks coated with desert varnish were collected from the Anza-Borrego Desert, California, USA, as well as soils from underneath the rocks. DNA from both varnish coatings and soil samples was extracted and subsequently used for metagenomic analysis, as well as for q-PCR analyses for specific species quantification. The element composition of the varnish coatings was analyzed and compared to the soil samples. Rock varnish shows similar depleted elements, compared to soil, but Mn and Pb are 50-60 times enriched compared to the soil samples, and about 100 times enriched compared to the upper continental crust. Our genomic analyses suggest unique populations and different protein functional groups occurring in the varnish compared to soil samples. We discuss these differences and try to shed light on the mechanism of Mn oxyhydroxide production in desert varnish formation.

  18. The Arduous Journey to Black-Hole Formation in Potential Gamma-Ray Burst Progenitors

    CERN Document Server

    Dessart, Luc; Ott, Christian D


    We present a quantitative study on the properties at death of fast-rotating massive stars evolved at low-metallicity, objects that are proposed as likely progenitors of long-duration gamma-ray bursts (LGRBs). We perform 1D+rotation stellar-collapse simulations on the progenitor models of Woosley & Heger (2006) and critically assess their potential for the formation of a black hole and a Keplerian disk (namely a collapsar) or a proto-magnetar. We note that theoretical uncertainties in the treatment of magnetic fields and the approximate handling of rotation compromises the accuracy of stellar-evolution models. We find that only the fastest rotating progenitors achieve sufficient compactness for black-hole formation while the bulk of models possess a core density structure typical of garden-variety core-collapse supernova (SN) progenitors evolved without rotation and at solar metallicity. Of the models that do have sufficient compactness for black-hole formation, most of them also retain a large amount of a...

  19. [Chlorination byproducts formation potentials of typical nitrogenous organic compounds in water]. (United States)

    Xu, Qian; Xu, Bin; Qin, Cao; Xia, Sheng-Ji; Gao, Nai-Yun; Tian, Fu-Xiang; Li, Da-Peng


    Twelve typical nitrogenous organic compounds including herbicides, pesticides, amino acids, industrial products etc in polluted raw water were selected to investigate formation of typical carbonaceous and nitrogenous DBPs during chlorination and chloramination. To indentify the formation mechanism of carbonaceous and nitrogenous disinfection byproducts from nitrogenous chemicals, chlorination and chloroamination of urea herbicides, triazine herbicides, amino acid, and other compounds were investigated. As a result, the potential precursors for different DBPs were defined as well. It has been identified that widely used urea herbicides could produce as many as 9 specific DBPs. The chlorotoluron shows highest reactivity and yields chloroform (CF), monochloroacetic acid (MCAA), dichloroacetic acid (DCAA), 1,1-dichloro-acetone (1,1-DCP), 1,1,1-trichloro-acetone (1,1,1-TCP), chloropicrin (NTCM), dichloro-acetonitrile (DCAN), dimethylnitrosamine (NDMA). The results indicated that aldicarb and dinoseb are important precursors of CF, DCAA, MCAA, NTCM as well. High concentrations of CF and DCAA were found during L-tryptophan chlorination. Furthermore, DBPs formation pathways and mechanisms were suggested during chlorination and chloramination of chlorotoluron, ametryn, dinoseb L-tryptophan.

  20. Anti-atherosclerotic potential of gossypetin via inhibiting LDL oxidation and foam cell formation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Jing-Hsien [School of Nutrition, Chung Shan Medical University, Taichung, Taiwan (China); Department of Medical Research, Chung Shan Medical University Hospital, Taichung, Taiwan (China); Tsai, Chia-Wen [Department of Nutrition, China Medical University, Taichung, Taiwan (China); Wang, Chi-Ping [Department of Clinical Laboratory, Chung Shan Medical University Hospital, Taichung, Taiwan (China); Lin, Hui-Hsuan, E-mail: [Department of Medical Research, Chung Shan Medical University Hospital, Taichung, Taiwan (China); School of Medical Laboratory and Biotechnology, Chung Shan Medical University, Taichung, Taiwan (China)


    Gossypetin, a flavone originally isolated from Hibiscus species, has been shown to possess antioxidant, antimicrobial, and antimutagenic activities. Here, we investigated the mechanism(s) underlying the anti-atherosclerotic potential of gossypetin. 1,1-Diphenyl-2-picrylhydrazyl (DPPH) scavenging activity assay showed that the addition of > 50 μM of gossypetin could scavenge over 50% of DPPH radicals. The inhibitory effects of gossypetin on the lipid and protein oxidation of LDL were defined by thiobarbituric acid reactive substance (TBARS) assay, the relative electrophoretic mobility (REM) of oxidized LDL (ox-LDL), and fragmentation of apoB in the Cu{sup 2+}-induced oxidation of LDL. Gossypetin showed potential in reducing ox-LDL-induced foam cell formation and intracellular lipid accumulation, and uptake ability of macrophages under non-cytotoxic concentrations. Molecular data showed that these influences of gossypetin might be mediated via peroxisome proliferator-activated receptor α (PPARα)/liver-X receptor α (LXRα)/ATP-binding cassette transporter A1 (ABCA1) and PPARγ/scavenger receptor CD36 pathways, as demonstrated by the transfection of PPARα siRNA or PPARγ expression vector. Our data implied that gossypetin regulated the PPAR signals, which in turn led to stimulation of cholesterol removal from macrophages and delay atherosclerosis. These results suggested that gossypetin potentially could be developed as an anti-atherosclerotic agent. - Highlights: • The anti-atherosclerotic effect of gossypetin in vitro was examined. • Gossypetin inhibited LDL oxidation. • Gossypetin showed potential in reducing on the formation of foam cells. • Gossypetin functions against ox-LDL through PPARa activation and PPARγ depression.

  1. Relation between soil matrix potential changes and water conversion ratios during methane hydrate formation processes in loess

    Institute of Scientific and Technical Information of China (English)

    Peng Zhang; Qingbai Wu; Guanli Jiang; Yibin Pu


    With a new apparatus designed and assembled by ourselves,the matrix potential of non-saturated loess was firstly measured and studied during methane hydrate formation processes.The experimental results showed that during two formation processes,the matrix potential changes of the loess all presented a good linear relationship with water conversion ratios.In addition,although it was well known that the secondary gas hydrate formation was easier than the initial,our experimental results showed that the initial hydrate formation efficiency in non-saturated loess was higher than that of the secondary.

  2. Mechanical strain promotes osteoblast ECM formation and improves its osteoinductive potential

    Directory of Open Access Journals (Sweden)

    Guo Yong


    Full Text Available Abstract Background The extracellular matrix (ECM provides a supportive microenvironment for cells, which is suitable as a tissue engineering scaffold. Mechanical stimulus plays a significant role in the fate of osteoblast, suggesting that it regulates ECM formation. Therefore, we investigated the influence of mechanical stimulus on ECM formation and bioactivity. Methods Mouse osteoblastic MC3T3-E1 cells were cultured in cell culture dishes and stimulated with mechanical tensile strain. After removing the cells, the ECMs coated on dishes were prepared. The ECM protein and calcium were assayed and MC3T3-E1 cells were re-seeded on the ECM-coated dishes to assess osteoinductive potential of the ECM. Results The cyclic tensile strain increased collagen, bone morphogenetic protein 2 (BMP-2, BMP-4, and calcium levels in the ECM. Compared with the ECM produced by unstrained osteoblasts, those of mechanically stimulated osteoblasts promoted alkaline phosphatase activity, elevated BMP-2 and osteopontin levels and mRNA levels of runt-related transcriptional factor 2 (Runx2 and osteocalcin (OCN, and increased secreted calcium of the re-seeded MC3T3-E1 cells. Conclusion Mechanical strain promoted ECM production of osteoblasts in vitro, increased BMP-2/4 levels, and improved osteoinductive potential of the ECM. This study provided a novel method to enhance bioactivity of bone ECM in vitro via mechanical strain to osteoblasts.

  3. Macrophage migration inhibitory factor enhances Pseudomonas aeruginosa biofilm formation potentially contributing to cystic fibrosis pathogenesis. (United States)

    Tynan, Aisling; Mawhinney, Leona; Armstrong, Michelle E; O'Reilly, Ciaran; Kennedy, Sarah; Caraher, Emma; Jülicher, Karen; O'Dwyer, David; Maher, Lewena; Schaffer, Kirsten; Fabre, Aurélie; McKone, Edward F; Leng, Lin; Bucala, Richard; Bernhagen, Jürgen; Cooke, Gordon; Donnelly, Seamas C


    Macrophage migration inhibitory factor (MIF) is a key proinflammatory mediator that we have previously shown to be associated with an aggressive clinical phenotype in cystic fibrosis. It possesses unique tautomerase enzymatic activity. However, to date, no human-derived substrate has been identified that has the capacity to interact with this cytokine's unique tautomerase activity. This led us to hypothesize that MIF may have the capacity to interact with external substrates. We describe for the first time how Pseudomonas aeruginosa can utilize human recombinant MIF (rMIF) to significantly (P < 0.01) enhance its endogenous biofilm formation. Our in vivo studies demonstrate that utilizing a small-molecular-weight inhibitor targeting MIF's tautomerase activity (SCD-19) significantly reduces the inflammatory response in a murine pulmonary chronic P. aeruginosa model. In addition, we show that in in vitro experiments, pretreatment of P. aeruginosa with rMIF is associated with reduced bacterial killing by tobramycin. Our novel findings support the concept of an anti-MIF strategy that targets this enzymatic activity as a potential future antibacterial therapeutic approach.-Tynan, A., Mawhinney, L., Armstrong, M. E., O'Reilly, C., Kennedy, S., Caraher, E., Jülicher, K., O'Dwyer, D., Maher, L., Schaffer, K., Fabre, A., McKone, E. F., Leng, L., Bucala, R., Bernhagen, J., Cooke, G., Donnelly, S. C. Macrophage migration inhibitory factor enhances Pseudomonas aeruginosa biofilm formation potentially contributing to cystic fibrosis pathogenesis. © FASEB.

  4. A multi-level strategy for anticipating future glacier lake formation and associated hazard potentials

    Directory of Open Access Journals (Sweden)

    H. Frey


    Full Text Available In the course of glacier retreat, new glacier lakes can develop. As such lakes can be a source of natural hazards, strategies for predicting future glacier lake formation are important for an early planning of safety measures. In this article, a multi-level strategy for the identification of overdeepened parts of the glacier beds and, hence, sites with potential future lake formation, is presented. At the first two of the four levels of this strategy, glacier bed overdeepenings are estimated qualitatively and over large regions based on a digital elevation model (DEM and digital glacier outlines. On level 3, more detailed and laborious models are applied for modeling the glacier bed topography over smaller regions; and on level 4, special situations must be investigated in-situ with detailed measurements such as geophysical soundings. The approaches of the strategy are validated using historical data from Trift Glacier, where a lake formed over the past decade. Scenarios of future glacier lakes are shown for the two test regions Aletsch and Bernina in the Swiss Alps. In the Bernina region, potential future lake outbursts are modeled, using a GIS-based hydrological flow routing model. As shown by a corresponding test, the ASTER GDEM and the SRTM DEM are both suitable to be used within the proposed strategy. Application of this strategy in other mountain regions of the world is therefore possible as well.

  5. Identification of a population of epidermal squamous cell carcinoma cells with enhanced potential for tumor formation.

    Directory of Open Access Journals (Sweden)

    Gautam Adhikary

    Full Text Available Epidermal squamous cell carcinoma is among the most common cancers in humans. These tumors are comprised of phenotypically diverse populations of cells that display varying potential for proliferation and differentiation. An important goal is identifying cells from this population that drive tumor formation. To enrich for tumor-forming cells, cancer cells were grown as spheroids in non-attached conditions. We show that spheroid-selected cells form faster growing and larger tumors in immune-compromised mice as compared to non-selected cells. Moreover, spheroid-selected cells gave rise to tumors following injection of as few as one hundred cells, suggesting these cells have enhanced tumor-forming potential. Cells isolated from spheroid-selected tumors retain an enhanced ability to grow as spheroids when grown in non-attached culture conditions. Thus, these tumor-forming cells retain their phenotype following in vivo passage as tumors. Detailed analysis reveals that spheroid-selected cultures are highly enriched for expression of epidermal stem cell and embryonic stem cell markers, including aldehyde dehydrogenase 1, keratin 15, CD200, keratin 19, Oct4, Bmi-1, Ezh2 and trimethylated histone H3. These studies indicate that a subpopulation of cells that possess stem cell-like properties and express stem cell markers can be derived from human epidermal cancer cells and that these cells display enhanced ability to drive tumor formation.

  6. Two Dimensional LIF Measurements and Potential Structure of Ion Beam Formation in an Argon Helicon Plasma (United States)

    Aguirre, Evan; Scime, Earl; Good, Timothy


    We report 2-dimensional, spatially resolved observations of ion beam formation in an expanding helicon plasma. Previous studies found that a current free double layer (CFDL) spontaneously arises at low pressure, below 1 mT. We use Laser Induced Fluorescence (LIF), a non-perturbative diagnostic to measure the ion velocity distribution functions (IVDFs) of argon ions both parallel and perpendicular to the background magnetic field. We report ion beam formation as a function of the expansion chamber magnetic field (0-108 G). The ion beam appears peaked in the center of the expansion chamber and decays over a few centimeters radially. We also report the potential structure of the plasma obtained with a planar Langmuir probe. To obtain meaningful Langmuir probe measurements, averages of tens of current-voltage are needed to reduce the effects of large electrostatic fluctuations that arise in plasmas that generate ion beams. We report the dependence of density, electron temperature, and floating potential on radial and axial position in the expansion plume. NSF Award PHYS-1360278.

  7. [Studies of ozone formation potentials for benzene and ethylbenzene using a smog chamber and model simulation]. (United States)

    Jia, Long; Xu, Yong-Fu


    Ozone formation potentials from irradiations of benzene-NO(x) and ethylbenzene-NO(x) systems under the conditions of different VOC/NO(x) ratios and RH were investigated using a characterized chamber and model simulation. The repeatability of the smog chamber experiment shows that for two sets of ethylbenzene-NO(x) irradiations with similar initial concentrations and reaction conditions, such as temperature, relative humidity and relative light intensity, the largest difference in O3 between two experiments is only 4% during the whole experimental run. On the basis of smog chamber experiments, ozone formation of photo-oxidation of benzene and ethylbenzene was simulated in terms of the master chemical mechanism (MCM). The peak ozone values for benzene and ethylbenzene simulated by MCM are higher than the chamber data, and the difference between the MCM-simulated results and chamber data increases with increasing RH. Under the conditions of sunlight irradiations, with benzene and ethylbenzene concentrations being in the range of (10-50) x 10(-9) and NO(x) concentrations in the range of (10-100) x 10(-9), the 6 h ozone contributions of benzene and ethylbenzene were obtained to be (3.1-33) x 10(-9) and (2.6-122) x 10(-9), whereas the peak O3 contributions of benzene and ethylbenzene were (3.5-54) x 10(-9) and (3.8-164) x 10(-9), respectively. The MCM-simulated maximum incremental reactivity (MIR) values for benzene and ethylbenzene were 0.25/C and 0.97/C (per carbon), respectively. The maximum ozone reactivity (MOR) values for these two species were obtained to be 0.73/C and 1.03/C, respectively. The MOR value of benzene from MCM is much higher than that obtained by carter from SAPRC, indicating that SAPRC may underestimate the ozone formation potential of benzene.

  8. Multiple formation mechanisms of ferrous olivine in CV carbonaceous chondrites during fluid-assisted metamorphism


    Krot, Alexander N.; Petaev,Michail I.; Bland, Phil A.


    The CV carbonaceous chondrites experienced alteration that resulted in formation of secondary ferrous olivine (Fa40-100), salite-hedenbergite pyroxenes (Fs10-50Wo45-50), wollastonite, andradite, nepheline, sodalite, phyllosilicates, magnetite, Fe,Ni-sulfides and Ni-rich metal in their Ca,Al-rich inclusions, amoeboid olivine ag-gregates, chondrules, and matrices. It has previously been suggested that fibrous ferrous olivine in dark inclusions in CV chondrites formed by dehydration of phyllosil...

  9. Pattern Formation in Swarming Spacecrafts using Tersoff-Brenner Potential Field

    Directory of Open Access Journals (Sweden)

    Zhifeng Zeng


    Full Text Available We present a distributed control strategy that lets a swarm of spacecrafts autonomously form a lattice in orbit around a planet. The system, based on the artificial potential field approach, proposes a novel way to divide the artificial field into two main terms: a global artificial potential field mainly based on the famous C-W equations that gathers the spacecrafts around a predefined meeting point, and a local term exploited the well-known Tersoff-Brenner potential that allows a spacecraft to place itself in the correct position relative to its closest neighbors. Moreover, in order to obtain convergence from all initial distributions of the spacecrafts, a dissipation term depended on the velocity of agent is introduced. The new methodology is demonstrated in the problem of forming a hexagon lattice, the structure unit of graphite. It is shown that a pattern formation can operate around a planet. By slightly changing the scenario our method can be easily applied to shape other configurations, such as a regular tetrahedron (with central point, the structure unit, etc.

  10. Formats

    Directory of Open Access Journals (Sweden)

    Gehmann, Ulrich


    Full Text Available In the following, a new conceptual framework for investigating nowadays’ “technical” phenomena shall be introduced, that of formats. The thesis is that processes of formatting account for our recent conditions of life, and will do so in the very next future. It are processes whose foundations have been laid in modernity and which will further unfold for the time being. These processes are embedded in the format of the value chain, a circumstance making them resilient to change. In addition, they are resilient in themselves since forming interconnected systems of reciprocal causal circuits.Which leads to an overall situation that our entire “Lebenswelt” became formatted to an extent we don’t fully realize, even influencing our very percep-tion of it.

  11. A potential cause for kidney stone formation during space flights: enhanced growth of nanobacteria in microgravity (United States)

    Ciftcioglu, Neva; Haddad, Ruwaida S.; Golden, D. C.; Morrison, Dennis R.; McKay, David S.


    BACKGROUND: Although some information is available regarding the cellular/molecular changes in immune system exposed to microgravity, little is known about the reasons of the increase in the kidney stone formation in astronauts during and/or after long duration missions at zero gravity (0 g). In our earlier studies, we have assessed a unique agent, nanobacteria (NB), in kidney stones and hypothesized that NB have an active role in calcium phosphate-carbonate deposition in kidney. In this research we studied effect of microgravity on multiplication and calcification of NB in vitro. METHODS: We examined NB cultures in High Aspect Rotating Vessels (HARVs) designed at the NASA's Johnson Space Center, which are designed to stimulate some aspects of microgravity. Multiplication rate and calcium phosphate composition of those NB were compared with NB cultured on stationary and shaker flasks. Collected aliquots of the cultures from different incubation periods were analyzed using spectrophotometer, SEM, TEM, EDX, and x-ray diffraction techniques. RESULTS: The results showed that NB multiplied 4.6x faster in HARVs compared to stationary cultures, and 3.2x faster than shaker flask conditions. X-ray diffraction and EDX analysis showed that the degree of apatite crystal formation and the properties of the apatite depend on the specific culture conditions used. CONCLUSION: We now report an increased multiplication rate of NB in microgravity-simulated conditions. Thus, NB infection may have a potential role in kidney stone formation in crew members during space flights. For further proof to this hypothesis, screening of the NB antigen and antibody level in flight crew before and after flight would be necessary.

  12. Metagenomic Analysis of Some Potential Nitrogen-Fixing Bacteria in Arable Soils at Different Formation Processes. (United States)

    Wolińska, Agnieszka; Kuźniar, Agnieszka; Zielenkiewicz, Urszula; Banach, Artur; Izak, Dariusz; Stępniewska, Zofia; Błaszczyk, Mieczysław


    The main goal of the study was to determine the diversity of the potential nitrogen-fixing (PNF) bacteria inhabiting agricultural (A) soils versus wastelands serving as controls (C). The soils were classified into three groups based on the formation process: autogenic soils (Albic Luvisols, Brunic Arenosols, Haplic Phaeozem) formed on loess material, hydrogenic soils (Mollic Gleysols, Eutric Fluvisol, Eutric Histosol) formed under the effect of stagnant water and lithogenic soils (Rendzina Leptosols) formed on limestone. In order to determine the preferable conditions for PNF bacteria, the relationships between the soil chemical features and bacterial operational taxonomic units (OTUs) were tested. Additionally, the nitrogen content and fertilisation requirement of the lithogenic (LG), autogenic (AG) and hydrogenic (HG) soils were discussed. The composition of the bacterial communities was analysed with the next-generation sequencing (NGS) by the Ion Torrent™ technology. The sequences were clustered into OTU based on a 99 % similarity threshold. The arable soils tested were distinctly dominated by β-Proteobacteria representatives of PNF bacteria belonging to the genus Burkholderia. Bacteria from the α-Proteobacteria class and Devosia genus were subdominants. A free-living Cyanobacteria population dominated in A rather than in C soils. We have found that both soil agricultural management and soil formation processes are the most conducive factors for PNF bacteria, as a majority of these microorganisms inhabit the AG group of soils, whilst the LG soils with the lowest abundance of PNF bacteria revealed the need for additional mineral fertilisation. Our studies have also indicated that there are close relationships between soil classification with respect to soil formation processes and PNF bacteria preference for occupation of soil niches.

  13. Dissolved Organic Carbon and Optical Properties as Indicators of Trihalomethane Formation Potential in an Agricultural Watershed (United States)

    Pellerin, B. A.; Bergamaschi, B. A.; Spencer, R. G.


    Elevated concentrations of dissolved organic carbon (DOC) in the Sacramento-San Joaquin Delta waters may result in the formation of high levels of carcinogenic disinfection byproducts such as trihalomethane during drinking water treatment. The importance of Central Valley agricultural lands as sources of DOC and THM- precursors upstream of the Delta is presently unknown. We are quantifying contributions of DOC and THM- precursors from the Willow Slough watershed, a 425 km2 agriculturally-dominated catchment. During 2006, water samples were collected weekly at the mouth of the watershed and analyzed for DOC concentrations, optical properties (UV absorbance and fluorescence), and trihalomethane formation potential (THMFP). Additional synoptic samples were collected seasonally (winter, spring, summer) from 16 watershed locations and analyzed for optical properties, DOC concentrations, and THMFP. DOC concentrations generally ranged from approximately 2 to 4 mg/L at the watershed outlet during winter and spring, but increased weekly to 8 mg/L following the onset of irrigation. The THMFP at the mouth of the water was correlated with DOC concentration (r2 = 0.87), with higher concentrations during high discharge events and lower concentrations during summer and prolonged rain-free periods. In addition, the species of THM varied between high and low-flow periods, with THM formation dominated by brominated species during low- flow periods and chlorinated species during rainfall-runoff events. Optical characterization of DOC via UV absorbance and fluorescence suggests changes in DOC composition between high- and low-flow periods, likely reflective of changing sources and flowpaths of runoff.


    Directory of Open Access Journals (Sweden)

    I. M. Gurova


    Full Text Available The modern Strauss–Howe generational theory created at the intersection of economic, sociological, historical and psychological Sciences. She focuses primarily on difference of attitudes of generations, due to the specific social environment, corresponding to a certain period of time. Such a perspective on issues related to the human factor in the economy, has recently attracted interest not only from researchers, but also finds application for solving practical problems in some fields of business.Subject / theme. The article is devoted to one of the urgent contemporary socio-economic problems – the issue of the formation and development of labor potential. In this context, the theory of generations is offered by the authors as a tool for the study of qualitative parameters of human resources and the planning of future work opportunities in our country. In particular, the article considers the main aspects of the classical version of the Strauss–Howe generational theory and its Russian adaptation. Statistics describing the General demographics and working population of Russia from the point of view of generational groups. On this basis, a forecast is made of the labor potential of the country in the long term structure, review and compare the basic values and business characteristics of its constituent generations. Problem areas for which use of generational approach is rational are revealed and the corresponding recommendations are made.Objectives. The purpose of this article is justification of the possible application of provisions of modern theories of generations to identify and predict the dynamics of qualitative characteristics of the domestic workforce, as well as the prospects of its use in order to control the formation and development of labor potential.Methods. Methodological basis of the presented work make comparative and economic-statistical and socio-cultural methods of analysis.Results. In the framework of this article

  15. In Vivo Differentiation Potential of Epiblast Stem Cells Revealed by Chimeric Embryo Formation

    Directory of Open Access Journals (Sweden)

    Yali Huang


    Full Text Available Chimera formation after blastocyst injection or morula aggregation is the principal functional assay of the developmental potential of mouse embryonic stem cells (ESCs. This property, which demonstrates functional equivalence between ESCs and the preimplantation epiblast, is not shared by epiblast stem cell (EpiSC lines. Here, we show that EpiSCs derived either from postimplantation embryos or from ESCs in vitro readily generate chimeras when grafted to postimplantation embryos in whole embryo culture. EpiSC derivatives integrate and differentiate to derivatives of all three embryonic germ layers and primordial germ cells. In contrast, grafted ESCs seldom proliferate in postimplantation embryos, and fail to acquire the identity of their host-derived neighbors. EpiSCs do not incorporate efficiently into embryonic day 8.5 embryos, a stage by which pluripotency has been lost. Thus, chimera formation by EpiSCs requires a permissive environment, the postimplantation epiblast, and demonstrates functional equivalence between this cell type and EpiSCs.

  16. Characterization of haloacetaldehyde and trihalomethane formation potentials during drinking water treatment. (United States)

    Mao, Yu-Qin; Wang, Xiao-Mao; Guo, Xian-Fen; Yang, Hong-Wei; Xie, Yuefeng F


    Haloacetaldehydes (HAs) are the third prevalent group of disinfection by-products (DBPs) of great health concern. In this study, their formation and speciation during chlorination were investigated for raw and process waters collected at three O3-biological activated carbon (BAC) advanced drinking water treatment plants. The results showed that all HA formation potentials (HAFPs) were highly enhanced whenever ozone was applied before or after conventional treatment. Sand filtration and BAC filtration could substantially reduce HAFPs. Trihalomethanes (THMs) were also measured to better understand the role of HAs in DBPs. Very different from HAFPs, THMFPs kept decreasing with the progress of treatment steps, which was mainly attributed to the different precursors for HAs and THMs. Brominated HAs were detected in bromide-containing waters. Chloral hydrate (CH) contributed from 25% to 48% to the total HAs formed in waters containing 100-150 μg L(-1) bromide, indicating the wide existence of other HAs after chlorination besides CH production. In addition, bromide incorporation factor (BIF) in HAs and THMs increased with the progress of treatment steps and the BIF values of THMs were generally higher than those of HAs. The BAC filtration following ozonation could significantly reduce HA precursors produced from ozonation but without complete removal. The brominated HAFPs in the outflow of BAC were still higher than their levels in the raw water. As a result, O3-BAC combined treatment was effective at controlling the total HAs, whereas it should be cautious for waters with high bromide levels.

  17. Characterization of disinfection byproduct formation potential in 13 source waters in China

    Institute of Scientific and Technical Information of China (English)

    Junzhi Zhang; Jianwei Yu; Wei An; Juan Liu; Yongjing Wang; Youjun Chen; Jia Tai; Min Yang


    The formation potential of four trihalomethanes (THMFP) and seven haloacetic acids (HAA7FP) in 13 source waters taken from four major water basin areas in China was evaluated using the simulated distribution system (SDS) chlorination method.The specific ultraviolet absorbance (SUVA254: the ratio of UV254 to dissolved organic carbon (DOC)), which ranged between 0.9 and 5.0 L/(mg·m), showed that the organic compounds in different source waters exhibited different reactivities with chlorine.The HAA7FP of source waters ranged from 20 to 448 μg/L and the THMFP ranged from 29 to 259 μg/L.The HAA7FP concentrations were higher than the THMFP concentrations in all but one of the samples.Therefore, the risks of haloacetic acids (HAAs) should be of concern in some source waters.TCM (chloroform) and BDCM (bromodichloromethane) were the major THM constituents, while TCAA (trichioroacetic acid) and DCAA (dichloroacetic acid) were the major HAA species.Br-THM (brominated THM species) were much higher than BrHAA (brominated HAA species), and the formation of Br-DBP (Br-THM and Br-HAA) should be of concern when the bromide concentration is over 100 μg/L.

  18. Identification of volatile organic compounds in suburban Bangkok, Thailand and their potential for ozone formation (United States)

    Suthawaree, Jeeranut; Tajima, Yosuke; Khunchornyakong, Alisa; Kato, Shungo; Sharp, Alice; Kajii, Yoshizumi


    Measurement of Volatile Organic Compound (VOC) was carried out in suburban Bangkok during July 2-8, 2008. Analysis was performed using GC-FID and GC-MS. High mixing ratios of VOCs detected during the morning and evening are most likely due to vehicular emissions. Averaged VOC mixing ratios revealed distinct difference between mixing ratios of weekdays and weekend, which the latter were found to be lower. The most abundance species were propane and toluene. Ratios of benzene over toluene suggested that additional toluene mixing ratios was owing to industrial emission, which was particularly larger during weekdays. Comparison between C2Cl4 and CH3Cl mixing ratios obtained for suburban Tokyo reveal a relatively lower influence of biomass burning than suburban Bangkok. Elucidating by Ozone Formation Potential, toluene was found to contribute the most to O3 production followed by ethylene, m-,p-xylene, and propylene.

  19. Physics of a partially ionized gas relevant to galaxy formation simulations -- the ionization potential energy reservoir

    CERN Document Server

    Vandenbroucke, Bert; Schroyen, Joeri; Jachowicz, Natalie


    Simulation codes for galaxy formation and evolution take on board as many physical processes as possible beyond the standard gravitational and hydrodynamical physics. Most of this extra physics takes place below the resolution level of the simulations and is added in a sub-grid fashion. However, these sub-grid processes affect the macroscopic hydrodynamical properties of the gas and thus couple to the on-grid physics that is explicitly integrated during the simulation. In this paper, we focus on the link between partial ionization and the hydrodynamical equations. We show that the energy stored in ions and free electrons constitutes a potential energy term which breaks the linear dependence of the internal energy on temperature. Correctly taking into account ionization hence requires modifying both the equation of state and the energy-temperature relation. We implemented these changes in the cosmological simulation code Gadget2. As an example of the effects of these changes, we study the propagation of Sedov-...

  20. Hydrocarbon source potential of the Santiago Formation, Oriente Basin, SE of Ecuador (United States)

    Gaibor, J.; Hochuli, J. P. A.; Winkler, W.; Toro, J.


    The Santiago Formation (Late Hettangian-Sinemurian), described in the area of Santiago in the Oriente Basin of eastern Ecuador, consists of three distinct sedimentary members. The Santiago River Member is composed of limestones and calcareous sandstones. The Yuquianza Member is a monotonous sequence of black shales. The Patuca Member consists of a sequence of sandstones, greywackes, and shales, intercalated with lava flows and dikes. The fine-grained sediments of the three members are characterized by a high content of particulate organic matter (POM). Palynofacies and rock-eval analyses indicate the predominance of kerogen types II and III, with HI values that indicate a moderate to low source potential. At the type locality, the organic matter is thermally mature and locally overmatures.

  1. The contribution of electrical synapses to field potential oscillations in the hippocampal formation. (United States)

    Posłuszny, Anna


    Electrical synapses are a type of cellular membrane junction referred to as gap junctions (GJs). They provide a direct way to exchange ions between coupled cells and have been proposed as a structural basis for fast transmission of electrical potentials between neurons in the brain. For this reason GJs have been regarded as an important component within the neuronal networks that underlie synchronous neuronal activity and field potential oscillations. Initially, GJs appeared to play a particularly key role in the generation of high frequency oscillatory patterns in field potentials. In order to assess the scale of neuronal GJs contribution to field potential oscillations in the hippocampal formation, in vivo and in vitro studies are reviewed here. These investigations have shown that blocking the main neuronal GJs, those containing connexin 36 (Cx36-GJs), or knocking out the Cx36 gene affect field potential oscillatory patterns related to awake active behavior (gamma and theta rhythm) but have no effect on high frequency oscillations occurring during silent wake and sleep. Precisely how Cx36-GJs influence population activity of neurons is more complex than previously thought. Analysis of studies on the properties of transmission through GJ channels as well as Cx36-GJs functioning in pairs of coupled neurons provides some explanations of the specific influence of Cx36-GJs on field potential oscillations. It is proposed here that GJ transmission is strongly modulated by the level of neuronal network activity and changing behavioral states. Therefore, contribution of GJs to field potential oscillatory patterns depends on the behavioral state. I propose here a model, based on large body of experimental data gathered in this field by several authors, in which Cx36-GJ transmission especially contributes to oscillations related to active behavior, where it plays a role in filtering and enhancing coherent signals in the network under high-noise conditions. In contrast

  2. Removal of disinfection by-products formation potential by biologically intensified process

    Institute of Scientific and Technical Information of China (English)

    AN Dong; LI Wei-guang; CUI Fu-yi; HE Xin; ZHANG Jin-song


    The removal of disinfection by-products formation potential(DBPFP) in artificially intensified biological activated carbon(IBAC) process which is developed on the basis of traditional ozone granular activated carbon was evaluated. By IBAC removals of 31% and 68% for THMFP and HAAFP were obtained respectively. Under identical conditions, the removals of the same substances were 4% and 32% respectively only by the granular activated carbon(GAC) process. Compared with GAC, the high removal rates of the two formed potential substances were due to the increasing of bioactivity of the media and the synergistic capabilities of biological degradation cooperating with activated carbon adsorption of organic compounds. A clear linear correlation ( R2 = 0.9562 and R2 = 0.9007) between DOC HAAFP removal rate and Empty Bed Contact Time(EBCT) of IBAC process was observed, while that between THMFP removal rate and EBCT of GAC was R2 = 0.9782. In addition certain linear correlations between THMFP, HAAFP and UV254 ( R2 = 0.855 and R2 = 0.7702) were found for the treated water. For IBAC process there are also more advantages such as long backwashing cycle time, low backwashing intensity and prolonging activated carbon lifetime and so on.

  3. In vitro screening of 50 highly prescribed drugs for thiol adduct formation--comparison of potential for drug-induced toxicity and extent of adduct formation. (United States)

    Gan, Jinping; Ruan, Qian; He, Bing; Zhu, Mingshe; Shyu, Wen C; Humphreys, W Griffith


    Reactive metabolite formation has been associated with drug-induced liver, skin, and hematopoietic toxicity of many drugs that has resulted in serious clinical toxicity, leading to clinical development failure, black box warnings, or, in some cases, withdrawal from the market. In vitro and in vivo screening for reactive metabolite formation has been proposed and widely adopted in the pharmaceutical industry with the aim of minimizing the property and thus the risk of drug-induced toxicity (DIT). One of the most common screening methods is in vitro thiol trapping of reactive metabolites. Although it is well-documented that many hepatotoxins form thiol adducts, there is no literature describing the adduct formation potential of safer drugs that are widely used. The objective of this study was to quantitatively assess the thiol adduct formation potential of 50 drugs (10 associated with DIT and 40 not associated) and document apparent differences in adduct formation between toxic and safer drugs. Dansyl glutathione was used as a trapping agent to aid the quantitation of adducts following in vitro incubation of drugs with human liver microsomes in the presence and absence of NADPH. Metabolic turnover of these drugs was also monitored by LC/UV. Overall, 15 out of the 50 drugs screened formed detectable levels of thiol adducts. There were general trends toward more positive findings in the DIT group vs the non-DIT group. These trends became more marked when the relative amount of thiol adducts was taken into account and improved further when dose and total daily reactive metabolite burdens were considered. In conclusion, there appears to be a general trend between the extent of thiol adduct formation and the potential for DIT, which would support the preclinical measurement and minimization of the property through screening of thiol adduct formation as part of an overall discovery optimization paradigm.

  4. Assessment of the potential for karst in the Rustler Formation at the WIPP site.

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz, John Clay


    This report is an independent assessment of the potential for karst dissolution in evaporitic strata of the Rustler Formation at the Waste Isolation Pilot Plant (WIPP) site. Review of the available data suggests that the Rustler strata thicken and thin across the area in depositional patterns related to lateral variations in sedimentary accommodation space and normal facies changes. Most of the evidence that has been offered for the presence of karst in the subsurface has been used out of context, and the different pieces are not mutually supporting. Outside of Nash Draw, definitive evidence for the development of karst in the Rustler Formation near the WIPP site is limited to the horizon of the Magenta Member in drillhole WIPP-33. Most of the other evidence cited by the proponents of karst is more easily interpreted as primary sedimentary structures and the localized dissolution of evaporitic strata adjacent to the Magenta and Culebra water-bearing units. Some of the cited evidence is invalid, an inherited baggage from studies made prior to the widespread knowledge of modern evaporite depositional environments and prior to the existence of definitive exposures of the Rustler Formation in the WIPP shafts. Some of the evidence is spurious, has been taken out of context, or is misquoted. Lateral lithologic variations from halite to mudstone within the Rustler Formation under the WIPP site have been taken as evidence for the dissolution of halite such as that seen in Nash Draw, but are more rationally explained as sedimentary facies changes. Extrapolation of the known karst features in Nash Draw eastward to the WIPP site, where conditions are and have been significantly different for half a million years, is unwarranted. The volumes of insoluble material that would remain after dissolution of halite would be significantly less than the observed bed thicknesses, thus dissolution is an unlikely explanation for the lateral variations from halite to mudstone and siltstone

  5. Assessment of potential radionuclide transport in site-specific geologic formations

    Energy Technology Data Exchange (ETDEWEB)

    Dosch, R.G.


    Associated with the development of deep, geologic repositories for nuclear waste isolation is a need for safety assessments of the potential for nuclide migration. Frequently used in estimating migration rates is a parameter generally known as a distribution coefficient, K/sub d/, which describes the distribution of a radionuclide between a solid (rock) and a liquid (groundwater) phase. This report is intended to emphasize that the use of K/sub d/ must be coupled with a knowledge of the geology and release scenarios applicable to a repository. Selected K/sub d/ values involving rock samples from groundwater/brine simulants typical of two potential repository sites, WIPP and NTS, are used to illustrate this concern. Experimental parameters used in K/sub d/ measurements including nuclide concentration, site sampling/rock composition, and liquid-to-solid ratios are discussed. The solubility of U(VI) in WIPP brine/groundwater was addressed in order to assess the potential contribution of this phenomena to K/sub d/ values. Understanding mehanisms of sorption of radionuclides on rocks would lead to a better predictive capability. Sorption is attributed to the presence of trace constituents (often unidentified) in rocks. An attempt was made to determine if this applied to WIPP dolomite rocks by comparing sorption behavior of the natural material with that of a synthetic dolomite prepared in the laboratory with reagent grade chemicals. The results were inconclusive. The results of a study of Tc sorption by an argillite sample from the Calico Hills formation at NTS under ambient laboratory conditions were more conclusive. The Tc sorption was found to be associated with elemental carbon. Available evidence points to a reduction mechanism leading to the apparent sorption of Tc on the solid phase.

  6. Primary Emission and the Potential of Secondary Aerosol Formation from Chinese Gasoline Engine Exhaust (United States)

    Hu, Min; Peng, Jianfei; Qin, Yanhong; Du, Zhuofei; Li, Mengjin; Zheng, Rong; Zheng, Jing; Shang, Dongjie; Lu, Sihua; Wu, Yusheng; Zeng, Limin; Guo, Song; Shao, Min; Wang, Yinhui; Shuai, Shijin


    Along with the urbanization and economic growth, vehicle population in China reached 269 million, ranked the second in the world in 2015. Gasoline vehicle is identified to be the main source for urban PM2.5 in China, accounting for 15%-31%. In this study the impact of fuel components on PM2.5 and volatile organic compounds (VOCs) emissions from a gasoline port fuel injection (PFI) engine and a gasoline direct injection (GDI) engine are discussed. Results show that, higher proportion of aromatics, alkenes or sulfur in gasoline fuel will lead to higher PM emissions. The PM from the PFI engine mainly consists of OC and a small amount of EC and inorganic ions, while the PM discharge from the GDI engine mainly consists of EC, OM and a small amount of inorganic ions. Since the GDI engines can reduce fuel consumption and CO2 emissions, and it would become more and more popular in the near future. The characteristics of POM component, emission factors and source profile were investigated from GDI engine, particularly focused on the effect of engine speed, load and the catalyst, which will be very much helpful for source identification as source indicators. Chamber experiments were conducted to quantify the potential of secondary aerosol formation from exhaust of a PFI gasoline engine and China V gasoline fuel. During 4-5 h simulation, equivalent to10 days of atmospheric photo-oxidation in Beijing, the extreme SOA production was 426 ± 85 mg/kg fuel, with high precursors and OH exposure. 14% of SOA measured in the chamber experiments could be explained through the oxidation of speciated single-ring aromatics. Unspeciated precursors, such as intermediate-volatility organic compounds and semi-volatility organic compounds, might be significant for SOA formation from gasoline VOCs. We concluded that reduction of emissions of aerosol precursor gases from vehicles is essential to mediate pollution in China.

  7. Formation of intrathermocline eddies at ocean fronts by wind-driven destruction of potential vorticity (United States)

    Thomas, Leif N.


    A mechanism for the generation of intrathermocline eddies (ITEs) at wind-forced fronts is examined using a high resolution numerical simulation. Favorable conditions for ITE formation result at fronts forced by "down-front" winds, i.e. winds blowing in the direction of the frontal jet. Down-front winds exert frictional forces that reduce the potential vorticity (PV) within the surface boundary in the frontal outcrop, providing a source for the low-PV water that is the materia prima of ITEs. Meandering of the front drives vertical motions that subduct the low-PV water into the pycnocline, pooling it into the coherent anticyclonic vortex of a submesoscale ITE. As the fluid is subducted along the outcropping frontal isopycnal, the low-PV water, which at the surface is associated with strongly baroclinic flow, re-expresses itself as water with nearly zero absolute vorticity. This generation of strong anticyclonic vorticity results from the tilting of the horizontal vorticity of the frontal jet, not from vortex squashing. During the formation of the ITE, high-PV water from the pycnocline is upwelled alongside the subducting low-PV surface water. The positive correlation between the ITE's velocity and PV fields results in an upward, along-isopycnal eddy PV flux that scales with the surface frictional PV flux driven by the wind. The relationship between the eddy and wind-induced frictional PV flux is nonlocal in time, as the eddy PV flux persists long after the wind forcing is shut off. The ITE's PV flux affects the large-scale flow by driving an eddy-induced transport or bolus velocity down the outcropping isopycnal layer with a magnitude that scales with the Ekman velocity.

  8. Assessment of the potential for ammonium nitrate formation and reaction in Tank 241-SY-101

    Energy Technology Data Exchange (ETDEWEB)

    Pederson, L.R.; Bryan, S.A.


    Two principal scenarios by which ammonium nitrate may be formed were considered: (a) precipitation of ammonium nitrate in the waste, and (b) ammonium nitrate formation via the gas phase reaction of ammonia and nitrogen dioxide. The first of these can be dismissed because ammonium ions, which are necessary for ammonium nitrate precipitation, can exist only in negligibly small concentrations in strongly alkaline solutions. Gas phase reactions between ammonia, nitrogen dioxide, and water vapor in the gas phase represent the most likely means by which ammonium nitrate aerosols could be formed in Tank 241-SY-101. Predicted ammonium nitrate formation rates are largely controlled by the concentration of nitrogen dioxide. This gas has not been detected among those gases vented from the wastes using Fourier Transform Infrared Spectrometry (FTIR) or mass spectrometry. While detection limits for nitrogen dioxide have not been established experimentally, the maximum concentration of nitrogen dioxide in the gas phase in Tank 241-SY-101 was estimated at 0.1 ppm based on calculations using the HITRAN data base and on FTIR spectra of gases vented from the wastes. At 50 C and with 100 ppm ammonia also present, less than one gram of ammonium nitrate per year is estimated to be formed in the tank. To date, ammonium nitrate has not been detected on HEPA filters in the ventilation system, so any quantity that has been formed in the tank must be quite small, in good agreement with rate calculations. The potential for runaway exothermic reactions involving ammonium nitrate in Tank 241-SY-101 is minimal. Dilution by non-reacting waste components, particularly water, would prevent hazardous exothermic reactions from occurring within the waste slurry, even if ammonium nitrate were present. 41 refs.

  9. Intermittent Hypoxia-Induced Carotid Body Chemosensory Potentiation and Hypertension Are Critically Dependent on Peroxynitrite Formation

    Directory of Open Access Journals (Sweden)

    Esteban A. Moya


    Full Text Available Oxidative stress is involved in the development of carotid body (CB chemosensory potentiation and systemic hypertension induced by chronic intermittent hypoxia (CIH, the main feature of obstructive sleep apnea. We tested whether peroxynitrite (ONOO−, a highly reactive nitrogen species, is involved in the enhanced CB oxygen chemosensitivity and the hypertension during CIH. Accordingly, we studied effects of Ebselen, an ONOO− scavenger, on 3-nitrotyrosine immunoreactivity (3-NT-ir in the CB, the CB chemosensory discharge, and arterial blood pressure (BP in rats exposed to CIH. Male Sprague-Dawley rats were exposed to CIH (5% O2, 12 times/h, 8 h/day for 7 days. Ebselen (10 mg/kg/day was administrated using osmotic minipumps and BP measured with radiotelemetry. Compared to the sham animals, CIH-treated rats showed increased 3-NT-ir within the CB, enhanced CB chemosensory responses to hypoxia, increased BP response to acute hypoxia, and hypertension. Rats treated with Ebselen and exposed to CIH displayed a significant reduction in 3-NT-ir levels (60.8 ± 14.9 versus 22.9 ± 4.2 a.u., reduced CB chemosensory response to 5% O2 (266.5 ± 13.4 versus 168.6 ± 16.8 Hz, and decreased mean BP (116.9 ± 13.2 versus 82.1 ± 5.1 mmHg. Our results suggest that CIH-induced CB chemosensory potentiation and hypertension are critically dependent on ONOO− formation.

  10. High-resolution seafloor features related to potential gas-hydrate formation off SW Taiwan (United States)

    Hsu, S.; Tsai, C.; Chen, S.; Shih, T.


    The area off SW Taiwan is considered as a high potential area for gas-hydrate formation. The gas-hydrate signature is indicated by the abundant presence of BSR (Bottom-Simulating-Reflector). High methane concentration is also shown in the bottom water near the seafloor. To have a better understanding, we have conducted deep-towed survey of side-scan sonar and sub-bottom profiler in several potential areas. Pockmarks are found in several places. Some are related to gas seeping. The gas seeps are especially obvious in high-resolution sub-bottom profilers. The high pore-pressure due to the charging of the gas has clearly uplifted a top layer of sediments. The pockmarks area usually accompany the presence of authigenic carbonate. In the image of side-scan sonar data, the irregular patterns of strong backscatter signal are associated with the gas seeping or pockmark sites. The presence of pockmarks or gas seeps could be related to structural faults. Because the NW convergence of the Philippine Sea plate relative to the Eurasian plate, the area off SW Taiwan in fact is under compression and has caused folds and faults. These structural faults provide efficient conduits for fluid to migrate upward. Thus, the pockmarks frequently appear near faults. In the water depth of about 450m, the upward gas even goes into water column and creates clear gas plume image in EK 500 data. The gas is inferred to be dissociated from gas-hydrate and can get into the atmosphere. The dissociation of gas-hydrate has probably also induced the instability of the seafloor off SW Taiwan and cuased submarine landslides.

  11. Ice Formation Potential of Laboratory Generated Biogenic and Anthropogenic-Biogenic SOA Particles (United States)

    Knopf, D. A.; Alpert, P. A.; Charnawskas, J. C.; Lambe, A. T.; Massoli, P.; Onasch, T. B.; Davidovits, P.; Worsnop, D. R.


    Secondary organic aerosol (SOA) is ubiquitous in the atmosphere and may play an important role in cloud glaciation processes. We investigated several laboratory generated SOA particles systems for their initial water uptake and ice formation propensity as a function of temperature, T, relative humidity with respect to water, RH, relative humidity with respect to ice, RHice, and for different humidification rates, cRHice. This includes pure SOA particles formed from α-pinene, isoprene, and longifolene volatile organic compound precursors with and without the presence of sulfate seed particles as well as oxidized soot and soot-coated α-pinene and naphthalene SOA with varying O/C ratios and coating thicknesses. Micro-spectroscopic chemical imaging using scanning transmission X-ray microscopy with near edge X-ray absorption fine structure spectroscopy (STXM/NEXAFS) is used to characterize SOA, SOA-sulfate, SOA-soot particles generated in the Boston College potential aerosol mass (PAM) flow reactor in relation to their ice nucleation behavior. Water uptake is consistently observed on SOA particles at RH=75% and 95% for 262 and 228 K, respectively, followed by homogeneous ice nucleation applying atmospherically relevant cRHice=1 % min-1. When cRHice=25 % min-1, ice nucleation is delayed by about 30-40% RHice and cannot be explained by homogeneous ice nucleation. This implies diffusion limitation of water into these potentially glassy or semi-solid organic particles resulting in non-equilibrium between ambient RH and particle water activity. These data will aid in our understanding of the role of organic particle phase states in response to changes in T and RH which is crucial information for prediction of atmospheric ice nucleation.

  12. Change in haloacetic acid formation potential during UV and UV/H2O2 treatment of model organic compounds. (United States)

    Sakai, Hiroshi; Autin, Olivier; Parsons, Simon


    Haloacetic acids (HAAs) are disinfection by-products produced by the chlorination of organic matter, including amino acids. Advanced oxidation processes are expected to be effective for the destruction of HAA precursors; however, recent studies have reported the possible failure of these processes to reduce HAA formation potential. This study examined HAA formation potential during the course of UV or UV/H2O2 treatment of three organic compounds: leucine, serine, and resorcinol. HAA formation potential decreased in the treatment of resorcinol, while the potential increased slightly in the treatment of serine and greatly increased for leucine. The chemical structure required for HAA formation was assumed to be produced during the course of UV/H2O2 treatment of leucine and serine. Also, H abstraction from the δ carbon was assumed to result from the initial degradation of leucine by the hydroxyl radical during the UV/H2O2 treatment. The hydroxyl radical may have further reacted with leucine moiety to shorten its carbon chain. This would have produced a chemical structure capable of forming HAA, thus increasing HAA formation potential.

  13. A songbird forebrain area potentially involved in auditory discrimination and memory formation

    Indian Academy of Sciences (India)

    Raphael Pinaud; Thomas A Terleph


    Songbirds rely on auditory processing of natural communication signals for a number of social behaviors, including mate selection, individual recognition and the rare behavior of vocal learning – the ability to learn vocalizations through imitation of an adult model, rather than by instinct. Like mammals, songbirds possess a set of interconnected ascending and descending auditory brain pathways that process acoustic information and that are presumably involved in the perceptual processing of vocal communication signals. Most auditory areas studied to date are located in the caudomedial forebrain of the songbird and include the thalamo-recipient field L (subfields L1, L2 and L3), the caudomedial and caudolateral mesopallium (CMM and CLM, respectively) and the caudomedial nidopallium (NCM). This review focuses on NCM, an auditory area previously proposed to be analogous to parts of the primary auditory cortex in mammals. Stimulation of songbirds with auditory stimuli drives vigorous electrophysiological responses and the expression of several activity-regulated genes in NCM. Interestingly, NCM neurons are tuned to species-specific songs and undergo some forms of experience-dependent plasticity in-vivo. These activity-dependent changes may underlie long-term modifications in the functional performance of NCM and constitute a potential neural substrate for auditory discrimination. We end this review by discussing evidence that suggests that NCM may be a site of auditory memory formation and/or storage.

  14. Formation potentials of typical DBPs and changes of genotoxicity for chlorinated tertiary effluent pretreated by ozone

    Institute of Scientific and Technical Information of China (English)

    CAO Nan; MIAO Tingting; LI Kuixiao; ZHANG Yu; YANG Min


    The effects of ozonation on the formation potential of typical disinfection byproducts (DBPs) and the changes of genotoxicity during post chlorination of tertiary effluent from a sewage treatment plant were investigated. Ozonation enhanced the yields of all detected chlorine DBPs except CHCl3. At a chlorine dose of 5 mg/L, the three brominated THMs and five HAAs increased, while chloroform decreased with the increase of ozone dose from 0 to 10 mg/L (ozone dose in consumption base). At a chlorine dose of 10 mg/L, the two mixed bromochloro species THMs and two dominant HAAs (DCAA and TCAA) firstly increased and then decreased with the increase of ozone dose, with the turning point approximately occurring at an ozone dose of 5 mg/L. The genotoxicity detected using umu test, on the other hand, was removed from 7 μg 4-NQO/L to a negligible level by ozonation under an ozone dose of 5 mg/L. Chlorination could further remove the genotoxicity to some extent. It was found that SUVA (UV absorbance divided by DOC concentration) might be used as an indicative parameter for monitoring the removal of genotoxicity during the oxidation.

  15. Direct measurements of the ozone formation potential from livestock and poultry waste emissions. (United States)

    Howard, Cody J; Kumar, Anuj; Mitloehner, Frank; Stackhouse, Kimberly; Green, Peter G; Flocchini, Robert G; Kleeman, Michael J


    The global pattern of expanding urban centers and increasing agricultural intensity is leading to more frequent interactions between air pollution emissions from urban and agricultural sources. The confluence of these emissions that traditionally have been separated by hundreds of kilometers is creating new air quality challenges in numerous regions across the United States. An area of particular interest is California's San Joaquin Valley (SJV), which has an agricultural output higher than many countries, a rapidly expanding human population, and ozone concentrations that are already higher than many dense urban areas. New regulations in the SJV restrict emissions of reactive organic gases (ROGs) from animal sources in an attempt to meet Federal and State ozone standards designed to protect human health. The objective of this work is to directly measure the ozone formation potential (OFP) of agricultural animal plus waste sources in representative urban and rural atmospheres using a transportable "smog" chamber. Four animal types were examined: beef cattle, dairy cattle, swine, and poultry. Emissions from each animal plus waste type were captured in a 1 m(3) Teflon bag, mixed with representative background NO(x) and ROG concentrations, and then exposed to UV radiation so that ozone formation could be quantified. The emitted ROG composition was also measured so that the theoretical incremental reactivity could be calculated for a variety of atmospheres and directly compared with the measured OFP under the experimental conditions. The results demonstrate that OFP associated with waste ROG emissions from swine (0.39 +/- 0.04 g-O(3) per g-ROG), beef cattle (0.51 +/- 0.10 g-O(3) per g-ROG), and dairy cattle (0.42 +/- 0.07 g-O(3) per g-ROG) are lower than OFP associated with ROG emissions from gasoline powered light-duty vehicles (LDV) (0.69 +/- 0.05 g-O(3) per g-ROG). The OFP of ROG emitted from poultry waste (1.35 +/- 0.73 g-O(3) per g-ROG) is approximately double the

  16. Formation of aqueous-phase α-hydroxyhydroperoxides (α-HHP): potential atmospheric impacts (United States)

    Zhao, R.; Lee, A. K. Y.; Soong, R.; Simpson, A. J.; Abbatt, J. P. D.


    The focus of this work is on quantifying the degree of the aqueous-phase formation of α-hydroxyhydroperoxides (α-HHPs) via reversible nucleophilic addition of H2O2 to aldehydes. Formation of this class of highly oxygenated organic hydroperoxides represents a poorly characterized aqueous-phase processing pathway that may lead to enhanced SOA formation and aerosol toxicity. Specifically, the equilibrium constants of α-HHP formation have been determined using proton nuclear-magnetic-resonance (1H NMR) spectroscopy and proton-transfer-reaction mass spectrometry (PTR-MS). Significant α-HHP formation was observed from formaldehyde, acetaldehyde, propionaldehyde, glycolaldehyde, glyoxylic acid, and methylglyoxal, but not from methacrolein and ketones. Low temperatures enhanced the formation of α-HHPs but slowed their formation rates. High inorganic salt concentrations shifted the equilibria toward the hydrated form of the aldehydes and slightly suppressed α-HHP formation. Using the experimental equilibrium constants, we predict the equilibrium concentration of α-HHPs to be in the μM level in cloud water, but it may also be present in the mM level in aerosol liquid water (ALW), where the concentrations of H2O2 and aldehydes can be high. Formation of α-HHPs in ALW may significantly affect the effective Henry's law constants of H2O2 and aldehydes but may not affect their gas-phase levels. The photochemistry and reactivity of this class of atmospheric species have not been studied.

  17. Formation of aqueous-phase α-hydroxyhydroperoxides (α-HHP: potential atmospheric impacts

    Directory of Open Access Journals (Sweden)

    R. Zhao


    Full Text Available The focus of this work is on quantifying the degree of the aqueous-phase formation of α-hydroxyhydroperoxides (α-HHPs via reversible nucleophilic addition of H2O2 to aldehydes. Formation of this class of highly oxygenated organic hydroperoxides represents a poorly characterized aqueous-phase processing pathway that may lead to enhanced SOA formation and aerosol toxicity. Specifically, the equilibrium constants of α-HHP formation have been determined using proton nuclear-magnetic-resonance (1H NMR spectroscopy and proton-transfer-reaction mass spectrometry (PTR-MS. Significant α-HHP formation was observed from formaldehyde, acetaldehyde, propionaldehyde, glycolaldehyde, glyoxylic acid, and methylglyoxal, but not from methacrolein and ketones. Low temperatures enhanced the formation of α-HHPs but slowed their formation rates. High inorganic salt concentrations shifted the equilibria toward the hydrated form of the aldehydes and slightly suppressed α-HHP formation. Using the experimental equilibrium constants, we predict the equilibrium concentration of α-HHPs to be in the μM level in cloud water, but it may also be present in the mM level in aerosol liquid water (ALW, where the concentrations of H2O2 and aldehydes can be high. Formation of α-HHPs in ALW may significantly affect the effective Henry's law constants of H2O2 and aldehydes but may not affect their gas-phase levels. The photochemistry and reactivity of this class of atmospheric species have not been studied.

  18. Evidence of syntectonic tephrites with nepheline in the Sidi Saïd Maâchou Cambrian basin (coastal Meseta, Morocco; geodynamic implications

    Directory of Open Access Journals (Sweden)

    El Hatimi, N.


    Full Text Available Based on a combined structural, petrographic, and geochemical analysis, a new interpretation of the basic magmatism of Sidi Saïd Maâchou (coastal Meseta in two stages of emplacement is proposed. The first stage is characterized by transitional pyroclastic flows that have accompanied the opening of the West-Mesetian basin, during the Cambrian; the second stage is made of dykes of basalts, dolerites, and tephrites bearing nepheline. The emplacement of this undersaturated alkaline magma is associated to a sinistral submeridian shear zone which has been activated at the end of the Caledonian orogenesis, by a mantellic advection.

    Basée sur des critères structuraux, pétrographiques et géochimiques, une réinterprétation du magmatisme basique de Sidi Saîd Maâchou (meseta côtière en deux stades de mise en place est proposée. Le premier stade est caractérisé par des coulées pyroclastiques transitionnelles accompagnant l’ouverture du bassin ouest mésétien au Cambrien. Le second stade, de nature fissural, comprend des basaltes, dolérites et téphrites à néphéline spécifiques d’un magmatisme alcalin sous-saturé. La mise en place de ce dernier est associée à un couloir de cisaillement senestre subméridien activé à la fin de l’orogenèse calédonienne, engendrant un flux géothermique élevé.

  19. The Wnt11 Signaling Pathway in Potential Cellular EMT and Osteochondral Differentiation Progression in Nephrolithiasis Formation. (United States)

    He, Deng; Lu, Yuchao; Hu, Henglong; Zhang, Jiaqiao; Qin, Baolong; Wang, Yufeng; Xing, Shuai; Xi, Qilin; Wang, Shaogang


    The molecular events leading to nephrolithiasis are extremely complex. Previous studies demonstrated that calcium and transforming growth factor-β1 (TGF-β1) may participate in the pathogenesis of stone formation, but the explicit mechanism has not been defined. Using a self-created genetic hypercalciuric stone-forming (GHS) rat model, we observed that the increased level of serous/uric TGF-β1 and elevated intracellular calcium in primary renal tubular epithelial cells (PRECs) was associated with nephrolithiasis progression in vivo. In the setting of high calcium plus high TGF-β1 in vitro, PRECs showed great potential epithelial to mesenchymal transition (EMT) progression and osteochondral differentiation properties, representing the multifarious increased mesenchymal and osteochondral phenotypes (Zeb1, Snail1, Col2A1, OPN, Sox9, Runx2) and decreased epithelial phenotypes (E-cadherin, CK19) bythe detection of mRNAs and corresponding proteins. Moreover, TGF-β-dependent Wnt11 knockdown and L-type Ca2+ channel blocker could greatly reverse EMT progression and osteochondral differentiation in PRECs. TGF-β1 alone could effectively promote EMT, but it had no effect on osteochondral differentiation in NRK cells (Rat kidney epithelial cell line). Stimulation with Ca2+ alone did not accelerate differentiation of NRK. Co-incubation of extracellular Ca2+ and TGF-β1 synergistically promotes EMT and osteochondral differentiation in NRK control cells. Our data supplied a novel view that the pathogenesis of calcium stone development may be associated with synergic effects of TGF-β1 and Ca2+, which promote EMT and osteochondral differentiation via Wnt11 and the L-type calcium channel.

  20. The Wnt11 Signaling Pathway in Potential Cellular EMT and Osteochondral Differentiation Progression in Nephrolithiasis Formation

    Directory of Open Access Journals (Sweden)

    Deng He


    Full Text Available The molecular events leading to nephrolithiasis are extremely complex. Previous studies demonstrated that calcium and transforming growth factor-β1 (TGF-β1 may participate in the pathogenesis of stone formation, but the explicit mechanism has not been defined. Using a self-created genetic hypercalciuric stone-forming (GHS rat model, we observed that the increased level of serous/uric TGF-β1 and elevated intracellular calcium in primary renal tubular epithelial cells (PRECs was associated with nephrolithiasis progression in vivo. In the setting of high calcium plus high TGF-β1 in vitro, PRECs showed great potential epithelial to mesenchymal transition (EMT progression and osteochondral differentiation properties, representing the multifarious increased mesenchymal and osteochondral phenotypes (Zeb1, Snail1, Col2A1, OPN, Sox9, Runx2 and decreased epithelial phenotypes (E-cadherin, CK19 bythe detection of mRNAs and corresponding proteins. Moreover, TGF-β-dependent Wnt11 knockdown and L-type Ca2+ channel blocker could greatly reverse EMT progression and osteochondral differentiation in PRECs. TGF-β1 alone could effectively promote EMT, but it had no effect on osteochondral differentiation in NRK cells (Rat kidney epithelial cell line. Stimulation with Ca2+ alone did not accelerate differentiation of NRK. Co-incubation of extracellular Ca2+ and TGF-β1 synergistically promotes EMT and osteochondral differentiation in NRK control cells. Our data supplied a novel view that the pathogenesis of calcium stone development may be associated with synergic effects of TGF-β1 and Ca2+, which promote EMT and osteochondral differentiation via Wnt11 and the L-type calcium channel.

  1. Seasonal and temporal patterns of NDMA formation potentials in surface waters. (United States)

    Uzun, Habibullah; Kim, Daekyun; Karanfil, Tanju


    The seasonal and temporal patterns of N-nitrosodimethylamine (NDMA) formation potentials (FPs) were examined with water samples collected monthly for 21 month period in 12 surface waters. This long term study allowed monitoring the patterns of NDMA FPs under dynamic weather conditions (e.g., rainy and dry periods) covering several seasons. Anthropogenically impacted waters which were determined by high sucralose levels (>100 ng/L) had higher NDMA FPs than limited impacted sources (spring months, while seasonal mean values remained relatively consistent. The study also showed that watershed characteristics played an important role in the seasonal and temporal patterns. In the two dam-controlled river systems (SW A and G), the NDMA FP levels at the downstream sampling locations were controlled by the NDMA levels in the dams independent of either the increases in discharge rates due to water releases from the dams prior to or during the heavy rain events or intermittent high NDMA FP levels observed at the upstream of dams. The large reservoirs and impoundments on rivers examined in this study appeared serving as an equalization basin for NDMA precursors. On the other hand, in a river without an upstream reservoir (SW E), the NDMA levels were influenced by the ratio of an upstream wastewater treatment plant (WWTP) effluent discharge to the river discharge rate. The impact of WWTP effluent decreased during the high river flow periods due to rain events. Linear regression with independent variables DOC, DON, and sucralose yielded poor correlations with NDMA FP (R(2) < 0.27). Multiple linear regression analysis using DOC and log [sucralose] yielded a better correlation with NDMA FP (R(2) = 0.53).

  2. Assessment of the Potential Role of Streptomyces in Cave Moonmilk Formation

    Directory of Open Access Journals (Sweden)

    Marta Maciejewska


    Full Text Available Moonmilk is a karstic speleothem mainly composed of fine calcium carbonate crystals (CaCO3 with different textures ranging from pasty to hard, in which the contribution of biotic rock-building processes is presumed to involve indigenous microorganisms. The real microbial input in the genesis of moonmilk is difficult to assess leading to controversial hypotheses explaining the origins and the mechanisms (biotic vs. abiotic involved. In this work, we undertook a comprehensive approach in order to assess the potential role of filamentous bacteria, particularly a collection of moonmilk-originating Streptomyces, in the genesis of this speleothem. Scanning electron microscopy (SEM confirmed that indigenous filamentous bacteria could indeed participate in moonmilk development by serving as nucleation sites for CaCO3 deposition. The metabolic activities involved in CaCO3 transformation were furthermore assessed in vitro among the collection of moonmilk Streptomyces, which revealed that peptides/amino acids ammonification, and to a lesser extend ureolysis, could be privileged metabolic pathways participating in carbonate precipitation by increasing the pH of the bacterial environment. Additionally, in silico search for the genes involved in biomineralization processes including ureolysis, dissimilatory nitrate reduction to ammonia, active calcium ion transport, and reversible hydration of CO2 allowed to identify genetic predispositions for carbonate precipitation in Streptomyces. Finally, their biomineralization abilities were confirmed by environmental SEM, which allowed to visualize the formation of abundant mineral deposits under laboratory conditions. Overall, our study provides novel evidences that filamentous Actinobacteria could be key protagonists in the genesis of moonmilk through a wide spectrum of biomineralization processes.

  3. Topological estimation of proton-ligand formation constants of potential antitumour agents: Salicylhydroxamic acids

    Indian Academy of Sciences (India)

    Sneha Karmarkar; P V Khadikar; Vijay K Agrawal; Keshav C Mathur; Manorama Mandloi; Shobha Joshi


    Proton-ligand formation constants of salicylhydroxamic acids (SHA) and their nuclear substituted derivatives have been estimated topologically using the normalized Wiener index, referred to as mean square Wiener index (Wms). Regression analysis of the data indicates that Wms can be used successfully for estimating and monitoring proton-ligand formation constants.

  4. Formation and fates of nitrosamines and their formation potentials from a surface water source to drinking water treatment plants in Southern Taiwan. (United States)

    Chen, Wei-Hsiang; Wang, Chung-Ya; Huang, Tsung-Hsien


    Nitrosamines are toxic and emerging disinfection byproducts. In this study, three drinking water treatment plants (DWTPs) in southern Taiwan treating the same source water in Gaoping River with comparable technologies were selected. The objective was to evaluate the formation and fates of six nitrosamines and their formation potentials (FPs) from a surface water source to drinking water. Albeit decreased further downstream in the river, four nitrosamine-FPs were observed in the source water due to anthropogenic pollution in the upstream areas. In the DWTPs, nitrosamines were formed and NDMA was the main species. While high organic carbon concentrations indicated elevated nitrosamine-FPs in the source water, NDMA formation in the DWTPs was more positively associated with reductions of water parameters that quantify organic matters with double bonded ring structures. Although precursor removal via pre-oxidation is a viable approach to limit nitrosamine formation during post-disinfection, this study clearly indicates that a great portion of NDMA in treated water has been formed in the 1st oxidation step of drinking water treatment. The pre-oxidation simulations in the lab demonstrated the impact of pre-chlorination on nitrosamine formation. Given the limited removal in conventional treatment processes, avoiding nitrosamine-FPs in sources and/or nitrosamine formation during pre-oxidation become important issues to control the threats of nitrosamines in drinking water. Under current circumstance in which pre-oxidation is widely used to optimize the treatment effectiveness in many DWTPs, its adverse effect by forming nitrosamines needs to be carefully minimized and using technologies other than pre-chlorination (e.g., pre-ozonation) may be considered. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Formation of aqueous-phase α-hydroxyhydroperoxides (α-HHP: potential atmospheric impacts

    Directory of Open Access Journals (Sweden)

    R. Zhao


    Full Text Available The focus of this work is on quantifying the degree of the aqueous-phase formation of α-hydroxyhydroperoxides (α-HHPs via reversible nucleophilic addition of H2O2 to aldehydes. Formation of this class of highly oxygenated organic hydroperoxides represents a poorly characterized aqueous-phase processing pathway that may lead to enhanced SOA formation and aerosol toxicity. Specifically, the equilibrium constants of α-HHP formation have been determined using proton nuclear resonance (1H NMR spectroscopy and proton transfer reaction mass spectrometry (PTR-MS. Significant α-HHP formation was observed from formaldehyde, acetaldehyde, propionaldehyde, glycolaldehyde, glyoxylic acid, methylglyoxal, but not from methacrolein and ketones. Low temperatures enhanced the formation of α-HHPs but slowed their formation rates. High inorganic salt concentrations shifted the equilibria toward the hydrated form of the aldehydes and slightly suppressed α-HHP formation. Using the experimental equilibrium constants, we predict the equilibrium concentration of α-HHPs to be in the μM level in cloud water but may be present in the mM level in aerosol liquid water (ALW, where the concentrations of H2O2 and aldehydes can be high. Formation of α-HHPs in ALW may significantly affect the effective Henry's law constants of H2O2 and aldehydes but may not affect their gas-phase levels. The photochemistry and reactivity of this class of atmospheric species have not been studied.

  6. Comparison of chlorination and chloramination in carbonaceous and nitrogenous disinfection byproduct formation potentials with prolonged contact time. (United States)

    Sakai, Hiroshi; Tokuhara, Shunsuke; Murakami, Michio; Kosaka, Koji; Oguma, Kumiko; Takizawa, Satoshi


    Due to decreasing water demands in Japan, hydraulic retention times of water in piped supply systems has been extended, resulting in a longer contact time with disinfectants. However, the effects of extended contact time on the formation of various disinfection byproducts (DBPs), including carbonaceous DBPs such as trihalomethane (THM) and haloacetic acid (HAA), and nitrogenous DBPs such as nitrosodimethylamine (NDMA) and nitrosomorpholine (NMor), have not yet been investigated in detail. Herein, we compared the formation of these DBPs by chlorination and chloramination for five water samples collected from rivers and a dam in Japan, all of which represent municipal water supply sources. Water samples were treated by either filtration or a combination of coagulation and filtration. Treated samples were subjected to a DBP formation potential test by either chlorine or chloramine for contact times of 1 day or 4 days. Four THM species, nine HAA species, NDMA, and NMor were measured by GC-ECD or UPLC-MS/MS. Lifetime cancer risk was calculated based on the Integrated Risk Information System unit risk information. The experiment and analysis focused on (i) prolonged contact time from 1 day to 4 days, (ii) reduction efficiency by conventional treatment, (iii) correlations between DBP formation potentials and water quality parameters, and (iv) the contribution of each species to total risk. With an increased contact time from 1 day to 4 days, THM formation increased to 420% by chloramination. Coagulation-filtration treatment showed that brominated species in THMs are less likely to be reduced. With the highest unit risk among THM species, dibromochloromethane (DBCM) showed a high correlation with bromine, but not with organic matter parameters. NDMA contributed to lifetime cancer risk. The THM formation pathway should be revisited in terms of chloramination and bromine incorporation. It is also recommended to investigate nitrosamine formation potential by

  7. The Dialogic Potential of ePortfolios: Formative Feedback and Communities of Learning within a Personal Learning Environment (United States)

    Ehiyazaryan-White, Ester


    This paper reports on the findings of a study into the use of ePortfolios as personal learning environments (PLE) by a group of students pursuing Master's degrees in Education. The qualitative study explores the potential of the ePortfolio to support learners in engaging in formative peer and tutor feedback as well as in developing a learning…

  8. Potential etiologic role of brushite in the formation of calcium (renal) stones (United States)

    Pak, Charles Y. C.


    Brushite may play an important regulatory role in the formation of calcium -containing renal stones. The urinary environment from patients with hypercalciuric nephrolithiasis is typically supersaturated and shows an increased propensity for the spontaneous nucleation of brushite. Brushite has been identified in "stone-forming" urine and in stones. This crystalline phase may undergo phase transformation to hydroxyapatite or cause heterogeneous nucleation or epitaxial growth of calcium oxalate. Thus, brushite may also participate in the formation of stones of hydroxypatite or calcium oxalate.

  9. Lithofacies Architecturing and Hydrocarbon Reservoir Potential of Lumshiwal Formation: Surghar Range, Trans-Indus Ranges, North Pakistan

    Directory of Open Access Journals (Sweden)

    Iftikhar Alam


    directed Paleo-current system prevailed during deposition of Lumshiwal Formation. Diagenetic and tectonically induced fractures make the formation exceedingly porous and permeable as suitable reservoir horizon for the accumulation of hydrocarbon in the Trans-Indus ranges. The same formation has already been proven as potential reservoir horizon for hydrocarbon in the Kohat Plateau of northwest Pakistan. Secondly, the formation is dominantly comprised of silica/quartz sandstone (quartzarenite which can be used as silica sand, one of the essential raw materials for glass industries. The formation is also comprised of local coal seams which can be mined for production of coal in the region.

  10. Naked singularity and black hole formation in self-similar Einstein-scalar fields with exponential potentials

    CERN Document Server

    Zhang, Xuefeng


    Motivated by cosmic censorship in general relativity and string theory, we extend Christodoulou's celebrated examples of naked singularity formation in the Einstein-massless scalar field system to include a positive or negative scalar potential of exponential forms, i.e., $V(\\phi)=\\pm\\exp(2\\phi/\\kappa)$ with a parameter $\\kappa$. Under spherical symmetry and a self-similar ansatz depending on $\\kappa$, we derive a 3-dimensional autonomous system of first-order ordinary differential equations, which incorporates the equations for massless scalar fields as a special case. Local behavior of the phase space is studied analytically with global solutions constructed numerically. Within the 3-dimensional solution manifold, we observe, for the negative potentials, naked singularity formation from nonsingular initial data for $\\kappa^2<1$. Meanwhile, transitions between solutions containing naked singularities and black holes are also identified. However, when the potential is taken positive, numerical evolutions r...

  11. Selective in situ potential-assisted SAM formation on multi electrode arrays (United States)

    Haag, Ann-Lauriene; Toader, Violeta; Lennox, R. Bruce; Grutter, Peter


    The selective modification of individual components in a biosensor array is challenging. To address this challenge, we present a generalizable approach to selectively modify and characterize individual gold surfaces in an array, in an in situ manner. This is achieved by taking advantage of the potential dependent adsorption/desorption of surface-modified organic molecules. Control of the applied potential of the individual sensors in an array where each acts as a working electrode provides differential derivatization of the sensor surfaces. To demonstrate this concept, two different self-assembled monolayer (SAM)-forming electrochemically addressable ω-ferrocenyl alkanethiols (C11) are chemisorbed onto independent but spatially adjacent gold electrodes. The ferrocene alkanethiol does not chemisorb onto the surface when the applied potential is cathodic relative to the adsorption potential and the electrode remains underivatized. However, applying potentials that are modestly positive relative to the adsorption potential leads to extensive coverage within 10 min. The resulting SAM remains in a stable state while held at potentials <200 mV above the adsorption potential. In this state, the chemisorbed SAM does not significantly desorb nor do new ferrocenylalkythiols adsorb. Using three set applied potentials provides for controlled submonolayer alkylthiol marker coverage of each independent gold electrode. These three applied potentials are dependent upon the specifics of the respective adsorbate. Characterization of the ferrocene-modified electrodes via cyclic voltammetry demonstrates that each specific ferrocene marker is exclusively adsorbed to the desired target electrode.

  12. The effect of temperature, interaction range, and pair potential on the formation of dodecagonal quasicrystals in core-corona systems (United States)

    Pattabhiraman, Harini; Dijkstra, Marjolein


    A two-dimensional dodecagonal quasicrystal was previously reported by Dotera et al (2014 Nature 506 208) in a system of particles interacting with a hard core of diameter σ and a repulsive square shoulder of diameter δ =1.40σ . In the current work, we examine the formation of this quasicrystal using bond orientational order parameters, correlation functions and tiling distributions. We find that this dodecagonal quasicrystal forms from a fluid phase. We further study the effect of the width of the repulsive shoulder by simulating the system over a range of values of δ. For the range of densities and temperatures considered, we observe the formation of the dodecagonal quasicrystal between δ =1.30σ and 1.44σ . We also study the effect of shape of the interaction potential by simulating the system using three other interaction potentials with two length scales, namely hard-core plus a linear ramp, modified exponential, or Buckingham (exp-6) potential. We observe the presence of the quasicrystal in all three systems. However, depending on the shape of the potential, the formation of the quasicrystal takes place at lower temperatures (or higher interaction strengths). Using free-energy calculations, we demonstrate that the quasicrystal is thermodynamically stable in the square-shoulder and linear-ramp system.

  13. Clay surface catalysis of formation of humic substances: potential role of maillard reactions (United States)

    The mechanisms of the formation of humic substances are poorly understood, especially the condensation of amino acids and reducing sugars products (Maillard reaction) in soil environments. Clay minerals behave as Lewis and Brönsted acids and catalyze several reactions and likely to catalyze the Mai...

  14. Lower miocene larger foraminifera and petroleum potential of the Tai Formation, Mergui Group, Andaman Sea (United States)

    Polachan, Songpope; Racey, Andrew

    Tertiary larger foraminifera are recorded for the first time from Thailand. The fauna studied is restricted mainly to the reefal carbonate of the Tai Formation, which rests unconformably on the pre-Late Eocene quartz-chlorite schist basement in the Central High region of the Mergui Basin. The formation is broadly correlatable with the Peutu Formation of the North Sumatra Basin. The Tai Formation can be divided into three units at the type locality; a basal unit of interbedded anhydrite, dolomite, shale and sandstone; a middle unit of coral/algal reefal limestones, and an upper unit of calcarenites interbedded with silty shales and sandstones. The middle and upper units have yielded a fauna comprising; Lepidocyclina (Nephrolepidina) japonica, Spiroclypeus yabeii, Cycloclypeus eidae, Cycloclypeus sp. A, Heterostegina sp. A, Lepidocyclina (N) sp. A, Miogypsina sp. A, and Miogypsinoides sp. L. (N) japonica and Miogypsinoides sp. can range up into the Middle Miocene (Lower Tf) whilst C. eidae can range down into the Upper Oligocene (Lower Te). The fauna is typical of the Indo-West Pacific Miocene faunal province of Adams (1970) and shows closer affinities to the faunas of Indonesia than those of India-Pakistan.

  15. Patterned electrospun nanofiber matrices via localized dissolution: potential for guided tissue formation. (United States)

    Jia, Chao; Yu, Dou; Lamarre, Marven; Leopold, Philip L; Teng, Yang D; Wang, Hongjun


    With the assistance of an ink-jet printer, solvent (the "ink") can be controllably and reproducibly printed onto electrospun nanofiber meshes (the "paper") to generate various micropatterns and subsequently guide distinct cellular organization and phenotype expression. In combination with the nanofiber-assisted layer-by-layer cell assembly, the patterned electrospun meshes will define an instructive microenvironment for guided tissue formation.

  16. Orthodontic treatment with fixed appliances and biofilm formation-a potential public health threat?

    NARCIS (Netherlands)

    Ren, Yijin; Jongsma, Marije A.; Mei, Li; van der Mei, Henny C.; Busscher, Henk J.

    OBJECTIVES: Orthodontic treatment is highly popular for restoring functional and facial esthetics in juveniles and adults. As a downside, prevalence of biofilm-related complications is high. Objectives of this review are to (1) identify special features of biofilm formation in orthodontic patients

  17. Orthodontic treatment with fixed appliances and biofilm formation-a potential public health threat?

    NARCIS (Netherlands)

    Ren, Yijin; Jongsma, Marije A.; Mei, Li; van der Mei, Henny C.; Busscher, Henk J.


    OBJECTIVES: Orthodontic treatment is highly popular for restoring functional and facial esthetics in juveniles and adults. As a downside, prevalence of biofilm-related complications is high. Objectives of this review are to (1) identify special features of biofilm formation in orthodontic patients a

  18. Geology and hydrocarbon potential of Dawson Bay Formation carbonate unit (Middle Devonian), Williston basin, North Dakota

    Energy Technology Data Exchange (ETDEWEB)

    Pound, W.


    The Middle Devonian Dawson Bay Formation carbonate unit is present in the subsurface of North Dakota except where truncated by postdepositional erosion. The carbonate unit thickens from the erosional limit to a maximum thickness of 47.5 m (156 ft) in Renville County and reaches a maximum depth of 3798 m (12,460 ft) below the surface in McKenzie County. In North Dakota, a submarine hardground separates the carbonate unit from the underlying second red bed member of the Dawson Bay Formation. The upper contact with the Souris River Formation is conformable except in those areas where the Dawson Bay Formation was exposed to subaerial erosion prior to deposition of the Souris River sediments. The Dawson Bay carbonate unit is predominantly dolomitic and fossiliferous limestone or fossiliferous dolostone. The carbonate unit can be subdivided into five lithofacies on the basis of characteristic fossil fauna, flora, and other lithologic features. Lithofacies analysis of the Dawson Bay carbonates suggests a shallowing-upward succession of depositional environments and associated energy zones as follows: shallow epeiric sea (very low energy), stromatoporoid biostrome/bioherm (low energy), very shallow epeiric sea (very low energy), restricted shallow epeiric sea (extremely low energy), and shallow epeiric sea shoreline (variable energy). Eogenetic diagenesis includes color-mottling, dolomitization of micrite to microcrystalline dolomite with penecontemporaneous anhydrite replacement of cryptalgal mudstones and boundstones, cementation by sparry calcite, and vuggy porosity development. Mesogenetic diagenesis includes formation of mosaic dolomites, cementation by blocky equant calcite, neomorphism, pressure-solution, fracturing, halite cementation, and hydrocarbon emplacement.

  19. Characterization of Natural Organic Matter and Disinfection Byproducts Formation Potential in Pilot-Scale Coagulation-Ultrafiltration Membrane Combined Process in Winter

    Institute of Scientific and Technical Information of China (English)

    张耀宗; 王启山; 何凤华; 丁莎莎


    A pilot-scale ultrafiltration membrane plant was set up for treating Luanhe River water with flocculating and precipitation process of waterworks.The aim is to investigate the variation and characteristics of natural organic matter and disinfection byproducts formation potential in the whole process in winter.The results show that dissolved organic matter(DOM),UV254,trihalomethanes formation potential(THMsFP) and haloacetic acids formation potential(HAAsFP) of Luanhe River water were mainly distributed in t...

  20. A method based on potential theory for calculating air cavity formation of an air cavity resistance reduction ship

    Institute of Scientific and Technical Information of China (English)

    LI Yun-bo; WU Xiao-yu; MA Yong; WANG Jin-guang


    This research is intended to provide academic reference and design guidance for further studies to determine the most effective means to reduce a ship's resistance through an air-cavity.On the basis of potential theory and on the assumption of an ideal and irrotational fluid,this paper drives a method for calculating air cavity formation using slender ship theory then points out the parameters directly related to the formation of air cavities and their interrelationships.Simulations showed that the formation of an air cavity is affected by cavitation number,velocity,groove geometry and groove size.When the ship's velocity and groove structure are given,the cavitation number must be within range to form a steady air cavity.The interface between air and water forms a wave shape and could be adjustedby an air injection system.

  1. Formation potentials of bromate and brominated disinfection by-products in bromide-containing water by ozonation. (United States)

    Lin, Tao; Wu, Shouke; Chen, Wei


    The ozonation involved in drinking water treatment raises issues of water quality security when the raw water contains bromide (Br(-)). Br(-) ions may be converted to bromate (BrO3 (-)) during ozonation and some brominated disinfection by-products (Br-DBPs) in the following chlorination. In this study, the effects of ozone (O3) dosage, contact time, pH, and Br(-) and ammonia (NH3-N) concentrations on the formation of BrO3 (-) and Br-DBPs have been investigated. The results show that decreasing the initial Br(-) concentration is an effective means of controlling the formation of BrO3 (-). When the concentration of Br(-) was lower than 100 μg/L, by keeping the ratio of O3 dosage to dissolved organic carbon (DOC) concentration at less than 1, BrO3 (-) production was effectively suppressed. The concentration of BrO3 (-) steadily increased with increasing O3 dosage at high Br(-) concentration (>900 μg/L). Additionally, a longer ozonation time increased the concentrations of BrO3 (-) and total organic bromine (TOBr), while it had less impact on the formation potentials of brominated trihalomethanes (Br-THMFP) and haloacetic acids (Br-HAAFP). Higher pH value and the presence of ammonia may lead to an increase in the formation potential of BrO3 (-) and Br-DBPs.

  2. Preliminary analyses of scenarios for potential human interference for repositories in three salt formations

    Energy Technology Data Exchange (ETDEWEB)


    Preliminary analyses of scenarios for human interference with the performance of a radioactive waste repository in a deep salt formation are presented. The following scenarios are analyzed: (1) the U-Tube Connection Scenario involving multiple connections between the repository and the overlying aquifer system; (2) the Single Borehole Intrusion Scenario involving penetration of the repository by an exploratory borehole that simultaneously connects the repository with overlying and underlying aquifers; and (3) the Pressure Release Scenario involving inflow of water to saturate any void space in the repository prior to creep closure with subsequent release under near lithostatic pressures following creep closure. The methodology to evaluate repository performance in these scenarios is described and this methodology is applied to reference systems in three candidate formations: bedded salt in the Palo Duro Basin, Texas; bedded salt in the Paradox Basin, Utah; and the Richton Salt Dome, Mississippi, of the Gulf Coast Salt Dome Basin.

  3. Gender aspects of formation of value potential of students’ physical training

    Directory of Open Access Journals (Sweden)

    Marchenko O. Iu.


    Full Text Available Purpose: study of gender peculiarities of formation of valuable orientations of students in physical education and sport. Material: in research students of 3 - 11 classes of secondary schools (419, with which the survey was conducted, were involved. Results : the absence of students' understanding of the necessity of motor activity to human health. Also development of adolescents values of physical culture and sports. Showing psychosocial characteristics to form a stable interest in the physical self. It was found that 15% of girls wish to play hockey on grass, athletic gymnastics, football and boxing. Conclusions: for the formation of valuable orientations of physical culture among students it is necessary to consider not only the physiological, morphological and psychological aspects, but also gender peculiarities of personality.

  4. The Wnt11 Signaling Pathway in Potential Cellular EMT and Osteochondral Differentiation Progression in Nephrolithiasis Formation


    Deng He; Yuchao Lu; Henglong Hu; Jiaqiao Zhang; Baolong Qin; Yufeng Wang; Shuai Xing; Qilin Xi; Shaogang Wang


    The molecular events leading to nephrolithiasis are extremely complex. Previous studies demonstrated that calcium and transforming growth factor-β1 (TGF-β1) may participate in the pathogenesis of stone formation, but the explicit mechanism has not been defined. Using a self-created genetic hypercalciuric stone-forming (GHS) rat model, we observed that the increased level of serous/uric TGF-β1 and elevated intracellular calcium in primary renal tubular epithelial cells (PRECs) was associated...

  5. Porosity and reservoir potentiality of the Cherahil Formation limestone (middle-upper Eocene) in the Gulf of Gabes (Tunisia) (United States)

    Njahi, Zahra; Kassabi, Nadhem; Touir, Jamel


    During the middle and upper Eocene, the deposits in the Gulf of Gabes correspond to the Cherahil Formation, which is sub-divided into three units, which are as follows from base to top: the Lower Cherahil A, the Siouf and the Upper Cherahil B members. The Siouf member has a lateral equivalent in the Souar Formation named Reineche member. The Cherahil Formation has never been considered by oil companies as a particular drilling target in the Gulf of Gabes (offshore east Tunisia) despite the presence of hydrocarbon at the bottom of Cherahil Formation in Sidi Behara and Sidi Litayem oil fields in Sfax Area (onshore east Tunisia) and in its equivalent carbonate beds in Jebel Trozza (Central Tunisia). Therefore, the evaluation of porosity in the carbonate levels of Cherahil Formation in 20 drilling wells were performed on well logging by applying Wyllie method. The obtained results show that the studied carbonates are characterized by an economically important total porosity average ranging between 5% and 55%, and both vertical and lateral variations. The vertical porosity variation was controlled by the sea-level fluctuation that, in turn, controlled the evolution of carbonate sedimentary environments and relative facies. The lateral porosity variation followed the Tunisian middle-upper Eocene paleogeography changes controlled by NW-SE synsedimentary tectonic trends. Considering the important features of the Cherahil Formation and the coexistence of components of an oil system in the Gulf of Gabes, this formation can be an important potential reservoir and subsequently a new petroleum exploration target in the Gulf of Gabes.

  6. PPARy phosphorylation mediated by JNK MAPK: a potential role in macrophage-derived foam cell formation

    Institute of Scientific and Technical Information of China (English)

    Ran YIN; Yu-gang DONG; Hong-lang LI


    Aim: To investigate whether oxidized low-density lipoprotein (ox-LDL) modulates peroxisome proliferator-activated receptor γ (PPARγ) activity through phosphorylation in macrophages, and the effect of PPARy phosphorylation on macrophages-derived foam cell formation. Methods: After exposing the cultured THP-1 cells to ox-LDL in the presence or absence of different mitogen-activated protein kinase (MAPK) inhibitors, PPARγ and phosphorylated PPARγ protein levels were detected by Western blot. MAPK activity was analyzed using MAP Kinase Assay Kit. Intracellular cholesterol accumulation was assessed by Oil red O staining and cholesterol oxidase enzymatic method. The Mrna level of PPARγ target gene was determined by reverse transcription-polymerase chain reaction (RT-PCR). Results: ox-LDL evaluated PPARγ phosphorylation status and subsequently decreased PPARγ target gene expression in a dose-dependent manner. Ox-LDL also induced MAPK activation. Treatment of THP-1 cells with c-Jun N-terminal kinase-, but not p38- or extracellular signal-regulated kinase-MAPK inhibitor, significantly suppressed PPARγ phosphorylation induced by ox-LDL, which in turn inhibited foam cell formation. Conclusion: In addition to its ligand-dependent activation, ox-LDL modulates PPARγ activity through phosphorylation, which is mediated by MAPK activation. PPARγ phosphorylation mediated by MAPK facilitates foam cell formation from macrophages exposed to ox-LDL.

  7. Influence of the Reform of Local Self-Government in Ukraine on the Formation and Development of Labor Potential

    Directory of Open Access Journals (Sweden)

    Kharuk Kateryna B.


    Full Text Available The article determines the peculiarities of formation and development of the labor potential in the process of the reforming local self-government in Ukraine. It has been found that an integration of population, the system of economic entities, infrastructure units, scientific-technical potential allows to determine the need for modern spatial forms of concentration of labor potential, i.e. for consolidated territorial communities. With the purpose of formation and development of labor potential, considering impacts of the reform of local self-government in Ukraine, the following activities has been proposed to be carried out: improving the living standards of rural residents, creation of productive jobs, socio-economic cooperation between communities, infrastructure development, use of natural resources, socio-labor, agricultural and industrial capacities, effective use of rural socio-labour potential, development of agricultural production, rural non-farm activities, development of social infrastructure, creation of advisory service and introduction of a system of continuous education, development of family medicine, collaboration with regional and central authorities, involvement of the regional budget funds, establishment of a fund for economic development, cooperation with domestic and foreign investors. It has been determined that the introduction of the above measures will affect the increase in employment within the consolidated territorial communities.

  8. Potential role for MATER in cytoplasmic lattice formation in murine oocytes.

    Directory of Open Access Journals (Sweden)

    Boram Kim

    Full Text Available BACKGROUND: Mater and Padi6 are maternal effect genes that are first expressed during oocyte growth and are required for embryonic development beyond the two-cell stage in the mouse. We have recently found that PADI6 localizes to, and is required for the formation of, abundant fibrillar Triton X-100 (Triton insoluble structures termed the oocyte cytoplasmic lattices (CPLs. Given their similar expression profiles and mutant mouse phenotypes, we have been testing the hypothesis that MATER also plays a role in CPL formation and/or function. METHODOLOGY/FINDINGS: Herein, we show that PADI6 and MATER co-localize throughout the oocyte cytoplasm following Triton extraction, suggesting that MATER co-localizes with PADI6 at the CPLs. Additionally, the solubility of PADI6 was dramatically increased in Mater(tm/tm oocytes following Triton extraction, suggesting that MATER is involved in CPL nucleation. This prediction is supported by transmission electron microscopic analysis of Mater(+/+ and Mater(tm/tm germinal vesicle stage oocytes which illustrated that volume fraction of CPLs was reduced by 90% in Mater(tm/tm oocytes compared to Mater(+/+ oocytes. CONCLUSIONS: Taken together, these results suggest that, similar to PADI6, MATER is also required for CPL formation. Given that PADI6 and MATER are essential for female fertility, these results not only strengthen the hypothesis that the lattices play a critical role in mediating events during the oocyte-to-embryo transition but also increase our understanding of the molecular nature of the CPLs.

  9. A Potential Mechanism for Perchlorate Formation on Mars: Surface-Radiolysis-Initiated Atmospheric Chemistry (United States)

    Wilson, Eric; Atreya, Sushil K.; Kaiser, Ralf-Ingo; Mahaffy, Paul


    Perchlorate (ClO4-) is prevalent on Earth, and with observations of perchlorate on lunar samples and chondrite meteorites, along with recent observations indicating the presence of perchlorate (ClO4-) in the Martian surface by the Phoenix lander and the Sample Analysis at Mars (SAM) on the Mars Science Laboratory (MSL) rover, it appears that the existence of perchlorate is widespread throughout the solar system. However, the abundance and isotopic composition of Martian perchlorate suggest that the perchlorate formation mechanism on Mars may involve a different path than perchlorate found elsewhere in the solar system. Motivated by this, we employ a one-dimensional chemical model to investigate the viability of perchlorate formation in the atmosphere of Mars, instigated by the radiolysis of the Martian surface by galactic cosmic rays. The surface-atmosphere interaction to produce Martian perchlorate involves the sublimation of chlorine oxides into the atmosphere, through surface radiolysis, and their subsequent synthesis to form perchloric acid (HClO4), followed by surface deposition and mineralization to form surface perchlorates. Considering the chlorine oxide, OClO, we find an OClO surface flux as low as 3.2x107 molecules cm-2 s-1, sublimated into the atmosphere from the surface could produce sufficient HClO4 to explain the perchlorate concentration on Mars, assuming an accumulation depth of 30 cm and integrated over the Amazonian period. Radiolysis provides an efficient pathway for the oxidation of chlorine, bypassing the efficient Cl/HCl recycling mechanism that characterizes HClO4 formation mechanisms proposed for the Earth but not Mars.

  10. Shaly sand formation evaluation in tight gas sands using electrochemical potential measurements (United States)

    Sharma, M. M.; Jin, M.


    Equations are developed that directly relate the shaly conductivity to the electrochemical (membrane) potential (EP). The model is applied to both fully and partially saturated sands. The relationship between the resistivity index and the water saturation is also expressed in terms of a single membrane potential measurement. The Ep measured at different salinities are compared with model prediction using a single membrane potential measurement. Sigma (sub 0) versus Sigma (sub w) curves are then generated using the model equations and compared with measured curves. Experimental results are presented for electrochemical potential measurement made in the lab on 50 tight gs sand samples. It is shown that the measurements can be correlated with CEC although the CEC measured by grinding up the samples was always higher than that estimated from Ep measurements. The Ep measurements are combined with the equations for partial saturation developed in the report to obtain water saturations in a tight gas sand well. Through the example it is shown that it is possible to determine the water saturation in Shaly sands from one membrane potential measurement at a known salinity together with a set of resistivity logs. The results clearly demonstrate the applicability of the method as a practical procedure for Shaly sand information evaluation.

  11. On the potential for regolith control of fluvial terrace formation in semi-arid escarpments (United States)

    Norton, K. P.; Schlunegger, F.; Litty, C.


    Cut-fill terraces occur throughout the western Andes, where they have been associated with pluvial episodes on the Altiplano. The mechanism relating increased rainfall to sedimentation is, however, not well understood. Here, we apply a hillslope sediment model and reported cosmogenic nuclide concentrations in terraces to examine terrace formation in semi-arid escarpment environments. We focus on the Pisco river system in western Peru in order to determine probable hillslope processes and sediment transport conditions during phases of terrace formation. Specifically, we model steady-state and transient hillslope responses to increased precipitation rates. The measured terrace distribution and sediment agree with the transient predictions, suggesting strong climatic control on the cut-fill sequences in western Peru primarily through large variations in sediment load. Our model suggests that the ultimate control for these terraces is the availability of sediment on the hillslopes, with hillslope stripping supplying large sediment loads early in wet periods. At the Pisco river, this is manifest as an approximately 4-fold increase in erosion rates during pluvial periods. We suggest that this mechanism may also control terrace occurrence other semi-arid escarpment settings.

  12. Seasonal Hypoxia Occurrence At Terengganu Estuary, Malaysia And its Potential Formation Mechanisms (United States)

    Lee, H. L.; Tangang, F.; Wahap, M. H.; YAng, S.


    Hypoxia is commonly defined as oxygen depletion when the dissolved oxygen (DO) levels fall below 2 mg L-1. In this paper, physical factors contributed to hypoxic condition in the diurnal tide, Terengganu Estuary has been experimentally and analytically studies. Hourly profiles on DO, current speed and nutrient were measured during the wet and dry seasons for continuous period approximately 30 hours, which cover both high and low tide at two fixed stations, located at the river mouth and 9.50 km upstream from the river mouth, respectively. It was observed that the entire estuary was free from hypoxia during the wet season. However, hypoxia was developed at the river mouth during the dry season with lowest reading of the DO level was 0.78 mg L-1. It was demonstrated that the combination of high contamination of nutrient, low current speed, the geometrical formation and water stratification are recognized as important role in formatting the hypoxia at the Terengganu river mouth.

  13. Stromal cell-derived factor-1 potentiates bone morphogenetic protein-2 induced bone formation. (United States)

    Higashino, Kosaku; Viggeswarapu, Manjula; Bargouti, Maggie; Liu, Hui; Titus, Louisa; Boden, Scott D


    The mechanisms driving bone marrow stem cell mobilization are poorly understood. A recent murine study found that circulating bone marrow-derived osteoprogenitor cells (MOPCs) were recruited to the site of recombinant human bone morphogenetic protein-2 (BMP-2)-induced bone formation. Stromal cell-derived factor-1α (SDF-1α) and its cellular receptor CXCR4 have been shown to mediate the homing of stem cells to injured tissues. We hypothesized that chemokines, such as SDF-1, are also involved with mobilization of bone marrow cells. The CD45(-) fraction is a major source of MOPCs. In this report we determined that the addition of BMP-2 or SDF-1 to collagen implants increased the number of MOPCs in the peripheral blood. BMP-2-induced mobilization was blocked by CXCR4 antibody, confirming the role of SDF-1 in mobilization. We determined for the first time that addition of SDF-1 to implants containing BMP-2 enhances mobilization, homing of MOPCs to the implant, and ectopic bone formation induced by suboptimal BMP-2 doses. These results suggest that SDF-1 increases the number of osteoprogenitor cells that are mobilized from the bone marrow and then home to the implant. Thus, addition of SDF-1 to BMP-2 may improve the efficiency of BMPs in vivo, making their routine use for orthopaedic applications more affordable and available to more patients.

  14. Cholesterol gallstones and bile host diverse bacterial communities with potential to promote the formation of gallstones. (United States)

    Peng, Yuhong; Yang, Yang; Liu, Yongkang; Nie, Yuanyang; Xu, Peilun; Xia, Baixue; Tian, Fuzhou; Sun, Qun


    The prevalence of cholesterol gallstones has increased in recent years. Bacterial infection correlates with the formation of gallstones. We studied the composition and function of bacterial communities in cholesterol gallstones and bile from 22 cholesterol gallstone patients using culture-dependent and culture-independent methods. Altogether fourteen and eight bacterial genera were detected in cholesterol gallstones and bile, respectively. Pseudomonas spp. were the dominant bacteria in both cholesterol gallstones and bile. As judged by diversity indices, hierarchical clustering and principal component analysis, the bacterial communities in gallstones were different from those in bile. The gallstone microbiome was considered more stable than that of bile. The different microbial communities may be partially explained by differences in their habitats. We found that 30% of the culturable strains from cholesterol gallstones secreted β-glucuronidase and phospholipase A2. Pseudomonas aeruginosa strains showed the highest β-glucuronidase activity and produced the highest concentration of phospholipase A2, indicating that Ps. aeruginosa may be a major agent in the formation of cholesterol gallstones. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Small-Angle Neutron Scattering and Spontaneous Formation of Unilamellar Vesicles: Potential Vehicles for Drug Delivery (United States)

    Katsaras, John


    Unilamellar vesicles (ULVs) are single-bilayer shells with radii commonly between 10 and 100 nm, and are widely used as model membranes, drug delivery systems, microreactors and substrates for a variety of enzymes and proteins. A common method of making ULVs is the extrusion of multilamellar vesicles (MLVs) through synthetic membranes of known pore size. These extruded ULVs are invariably unstable and in due time, revert back to MLVs. Over the years there have been reports of the spontaneous formation of stable ULVs in surfactant, lipid, and lipid/detergent mixtures. These ULVs have sometimes been shown to be monodisperse and their radii were found, almost without exception, to vary with concentration. We have carried-out small-angle neutron scattering (SANS) experiments on a biomimetic system composed of the phospholipids dimyristoyl and dihexanoyl phosphorylcholine (DMPC and DHPC, respectively). Doping DMPC/DHPC multilamellar vesicles with either the negatively charged lipid dimyristoyl phosphorylglycerol (DMPG, net charge -1) or the divalent cation, calcium (Ca2+) leads to the spontaneous formation of monodisperse unilamellar vesicles whose radii are concentration independent, in contrast to previous experimental observations.

  16. Isolation of Toxoplasma gondii development mutants identifies a potential proteophosphogylcan that enhances cyst wall formation. (United States)

    Craver, Mary Patricia J; Rooney, Peggy J; Knoll, Laura J


    Within warm-blooded animals, Toxoplasma gondii switches from an actively replicating form called a tachyzoite into a slow growing encysted form called a bradyzoite. To uncover the genes involved in bradyzoite development, we screened over 8000 T. gondii insertional mutants by immunofluorescence microscopy. We identified nine bradyzoite development mutants that were defective in both cyst wall formation and expression of a bradyzoite specific heat shock protein. One of these mutants, named 42F5, contained an insertion into the predicted gene TGME49_097520. The disrupted protein is serine/proline-rich with homology to proteophosphoglycans from Leishmania. T. gondii proteophosphoglycan (GU182879) expressed from the native promoter was undetectable in tachyzoites, but bradyzoites show punctate spots within the parasite and staining around the parasitophorous vacuole. Complementation of the 42F5 mutant with GU182879 expressed from either the alpha-tubulin or native promoter restores cyst wall formation. Overall, GU182879 is upregulated in bradyzoites and enhances cyst wall component expression and assembly.

  17. Formation of recent Pb-Ag-Au mineralization by potential sub-surface microbial activity. (United States)

    Tornos, Fernando; Velasco, Francisco; Menor-Salván, César; Delgado, Antonio; Slack, John F; Escobar, Juan Manuel


    Las Cruces is a base-metal deposit in the Iberian Pyrite Belt, one of the world's best-known ore provinces. Here we report the occurrence of major Pb-Ag-Au mineralization resulting from recent sub-surface replacement of supergene oxyhydroxides by carbonate and sulphide minerals. This is probably the largest documented occurrence of recent microbial activity producing an ore assemblage previously unknown in supergene mineralizing environments. The presence of microbial features in the sulphides suggests that these may be the first-described natural bacteriomorphs of galena. The low δ(13)C values of the carbonate minerals indicate formation by deep anaerobic microbial processes. Sulphur isotope values of sulphides are interpreted here as reflecting microbial reduction in a system impoverished in sulphate. We suggest that biogenic activity has produced around 3.1 × 10(9) moles of reduced sulphur and 10(10) moles of CO2, promoting the formation of ca. 1.19 Mt of carbonates, 114,000 t of galena, 638 t of silver sulphides and 6.5 t of gold.

  18. On the formation and evolution of asteroid belts and their potential significance for life

    CERN Document Server

    Martin, Rebecca G


    Suggestions have been made that asteroid belts may be important both for the existence of life and perhaps even for the evolution of complex life on a planet. Using numerical models for protoplanetary discs we calculate the location of the snow line, and we propose that asteroid belts are most likely to form in its vicinity. We then show that observations of warm dust in exo-solar systems, thought to be produced by collisions between asteroids in a belt, indicate that asteroid belts (when they exist), indeed coincide with the radial location and the temperature of the snow line. Giant planets form outside the snow line and prevent planet formation just inside of their orbit creating an asteroid belt there. However, the migration of giant planets through the asteroid belt likely disperses the compact formation. We examine existing observations of giant exo-planets and find that less than 4% are at radial locations outside of the snow line. This definitely may be the consequence of observational selection effec...

  19. Issues Of Labour Potential Growth And Effective Formation Of Employment Structure In Uzbekistan

    Directory of Open Access Journals (Sweden)

    Muyassar Mirzakarimova


    Full Text Available This article studies how to bring the human labour potentials in compliance with the demand in labour market both qualitatively and quantitatively.  Since the early years of the Independence a great attention is being paid to a human factor in Uzbekistan. A human potential is determined by such indicators as population size, their physical and intellectual, spiritual wellness and educational level. Society is related with labour potential growth, demographic processes, degree of public economic activeness. Due to expanded human reproduction, the amount of work resource is increasing.  In the article the impact of demographic condition in Uzbekistan and training system of skilled personnel on labour market was analyzed.  Such research methods as systematic approach, economic analysis, quantity, comparative and structural analysis were broadly used throughout the article.     


    The high use of nitro musk xylene (MX) and musk ketone (MK) as fragrances, and their persistence and bioaccumulation potential make them ubiquitous environmental contaminants. The 4-amino-MX (AMX) and 2-amino-MK (AMK) metabolites have been detected in trout fish hemoglobin (Hb) s...


    Directory of Open Access Journals (Sweden)

    S. V. Myamlin


    Full Text Available Purpose. The study involves the analysis of stages, formation forms and methods of the scientific potential of Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan (DNURT and contribution of its staff in the development of national and world science. Methogology. The use of historical and chronological, comparative, descriptive methods of research, systematization and analysis of archival documents of domestic and foreign funds allows identifying formation forms and means of scientific potential of DNURT over the 85 years of its existence. The periodization method makes it possible to distinguish the main stages and peculiarities of this process. The methods of analysis and synthesis as well as methods of expert assessments were applied. Findings. On the basis of a detailed analysis of the considerable archival documents array the basic stages of scientific potential formation of DNURT in the 85 years of its existence were highlighted. Their features with taking into account the historical and social conditions as well as contribution of university faculty generations (and some individuals in this process were determined. The forms and methods of continuity of scientific personnel and the impact of their research within the academic schools, formed at the Dnipropetrovsk Institute of Engineers of Railway Transport (DIERT were analyzed. Up to the presentthey play a significant role in strengthening the authority of DNURT as a leading national institution of higher education and principal scientific organization in the field of railway transport and transport construction. Main stages of the University formation beginning from specialized industry institution to the Polytechnic Research University with modern scientific base for theoretical and experimental research were highlighted. Originality. In the research context concerning reforming problems of higher education system as one of the areas of generation

  2. Resveratrol--a potential inhibitor of biofilm formation in Vibrio cholerae. (United States)

    Augustine, Nimmy; Goel, A K; Sivakumar, K C; Kumar, R Ajay; Thomas, Sabu


    Resveratrol, a phytochemical commonly found in the skin of grapes and berries, was tested for its biofilm inhibitory activity against Vibrio cholerae. Biofilm inhibition was assessed using crystal violet assay. MTT assay was performed to check the viability of the treated bacterial cells and the biofilm architecture was analysed using confocal laser scanning microscopy. The possible target of the compound was determined by docking analysis. Results showed that subinhibitory concentrations of the compound could significantly inhibit biofilm formation in V. cholerae in a concentration-dependent manner. AphB was found to be the putative target of resveratrol using docking analysis. The results generated in this study proved that resveratrol is a potent biofilm inhibitor of V. cholerae and can be used as a novel therapeutic agent against cholera. To our knowledge, this is the first report of resveratrol showing antibiofilm activity against V. cholerae.

  3. Shear-Induced Amyloid Formation in the Brain: I. Potential Vascular and Parenchymal Processes. (United States)

    Trumbore, Conrad N


    Shear distortion of amyloid-beta (Aβ) solutions accelerates amyloid cascade reactions that may yield different toxic oligomers than those formed in quiescent solutions. Recent experiments indicate that cerebrospinal fluid (CSF) and interstitial fluid (ISF) containing Aβ flow through narrow brain perivascular pathways and brain parenchyma. This paper suggests that such flow causes shear distortion of Aβ molecules involving conformation changes that may be one of the initiating events in the etiology of Alzheimer's disease. Aβ shearing can occur in or around brain arteries and arterioles and is suggested as the origin of cerebral amyloid angiopathy deposits in cerebrovascular walls. Comparatively low flow rates of ISF within the narrow extracellular spaces (ECS) of the brain parenchyma are suggested as a possible initiating factor in both the formation of neurotoxic Aβ42 oligomers and amyloid fibrils. Aβ42 in slow-flowing ISF can gain significant shear energy at or near the walls of tortuous brain ECS flow paths, promoting the formation of a shear-distorted, excited state hydrophobic Aβ42* conformation. This Aβ42* molecule could possibly be involved in one of two paths, one involving rapid adsorption to a brain membrane surface, ultimately forming neurotoxic oligomers on membranes, and the other ultimately forming plaque within the ECS flow pathways. Rising Aβ concentrations combined with shear at or near critical brain membranes are proposed as contributing factors to Alzheimer's disease neurotoxicity. These hypotheses may be applicable in other neurodegenerative diseases, including tauopathies and alpha-synucleinopathies, in which shear-distorted proteins also may form in the brain ECS.

  4. The potential impact of turbulent velocity fluctuations on drizzle formation in Cumulus clouds in an idealized 2D setup

    CERN Document Server

    Andrejczuk, M; Blyth, A


    This article discusses a potential impact of turbulent velocity fluctuations of the air on a drizzle formation in Cumulus clouds. Two different representations of turbulent velocity fluctuations for a microphysics formulated in a Lagrangian framework are discussed - random walk model and the interpolation, and its effect on microphysical properties of the cloud investigated. Turbulent velocity fluctuations significantly enhances velocity differences between colliding droplets, especially those having small sizes. As a result drizzle forms faster in simulations including a representation of turbulence. Both representations of turbulent velocity fluctuations, random walk and interpolation, have similar effect on droplet spectrum evolution, but interpolation of the velocity does account for a possible anisotropy in the air velocity. All discussed simulations show relatively large standard deviation ($\\sim$1${\\mu}m$) of the cloud droplet distribution from the onset of cloud formation is observed. Because coalesen...

  5. Characterization of Green Liquor Dregs, Potentially Useful for Prevention of the Formation of Acid Rock Drainage


    Maria Mäkitalo; Christian Maurice; Yu Jia; Björn Öhlander


    Using alternative materials such as residual products from other industries to mitigate the negative effects of acid rock drainage would simultaneously solve two environmental problems. The main residual product still landfilled by sulphate paper mills is the alkaline material green liquor dregs (GLD). A physical, mineralogical and chemical characterization of four batches of GLD was carried out to evaluate the potential to use it as a sealing layer in the construction of dry covers on sulphi...

  6. Influence of amine structural characteristics on N-nitrosamine formation potential relevant to postcombustion CO2 capture systems. (United States)

    Dai, Ning; Mitch, William A


    Concerns have arisen for the possible contamination of air or drinking water supplies downwind of amine-based CO2 capture facilities by potentially carcinogenic N-nitrosamines formed from reactions between flue gas NOx and amine solvents. This study evaluated the influence of amine structure on the potential to form total N-nitrosamines within the absorber and washwater units of a laboratory-scale CO2 capture reactor, and in the solvent after a pressure-cooker treatment as a mimic of desorber conditions. Among 16 amines representing 3 amine classes (alkanolamines, straight-chain and cyclic diamines, and amino acids), the order of the amine was the primary determinant of total N-nitrosamine formation in the absorber unit, with total N-nitrosamine formation in the order: secondary amines ≈ tertiary amines ≫ primary amines. Similar results were observed upon pressure-cooker treatment, due to reactions between nitrite and amines at high temperature. For secondary and tertiary amines, total N-nitrosamine formation under these desorber-like conditions appeared to be more important than in the absorber, but for primary amines, significant formation of total N-nitrosamines was only observed in the absorber. For diamines and amino acids, total N-nitrosamine accumulation rates in washwaters were lowest for primary amines. For alkanolamines, however, total N-nitrosamine accumulation in the washwater was similar regardless of alkanolamine order, due to the combined effects of amine reactivity toward nitrosation and amine volatility. While total N-nitrosamine accumulation rates in washwaters were generally 1-2 orders of magnitude lower than in the absorber, they were comparable to absorber rates for several primary amines. Decarboxylation of the amino acid sarcosine resulted in the accumulation of significant concentrations of N-nitrosodimethylamine and N-nitrodimethylamine in the washwater.

  7. Potential origin and formation for molecular components of humic acids in soils (United States)

    Hatcher, Patrick; DiDonato, Nicole; Waggoner, Derek


    Humification is defined as the process by which plant and microbial debris are transformed in to humic substances. Proposed pathways for the formation of humic substances, include the lignin and lignin decomposition theories, the lignin-polyphenol theory as well as the melanoidin pathway. It is generally accepted that a combination of several of these pathways with some modifications may be responsible for producing humic substances. The current study examines humic acids from numerous soil samples to demonstrate their molecular composition. In addition we provide an explanation for the formation of these molecules that introduces a new perspective of the humification process. Our work utilizes advanced analytical techniques such as ESI-FTICR-MS and solid state NMR to more completely characterize humic acids at the molecular level. Methods Humic acids were extracted from soils using 0.5 M NaOH followed by treatment with a Dowex™ ion-exchange resin to remove sodium ions. Solid State 13C NMR spectra were obtained on a Bruker 400 MHz Avance II spectrometer equipped with a 4 mm solid state MAS probe. ESI-FTICR-MS analysis was conducted in the negative ion mode on a Bruker Daltonics 12 Tesla Apex Qe FTICR-MS instrument equipped with an Apollo II ESI source. Results: Soil humic acids from numerous soils were investigated in this study. The molecular formulas calculated from ultrahigh resolution mass spectra of well humified soils fall clearly into two predominant regions consisting of condensed aromatic molecules as well as high H/C, low O/C carboxyl-containing aliphatic molecules (CCAM). In contrast, the spectral data for humic acids from a poorly humified spodosol soil show a less dramatic separation of these regions, with relatively more molecular formula plotting in the lignin-like region and relatively fewer condensed aromatic molecules. From the mass spectral observations made for the humic acids, we can readily discern a relationship based on degree of

  8. Sequential Treatment with SDF-1 and BMP-2 Potentiates Bone Formation in Calvarial Defects. (United States)

    Hwang, Hee-Don; Lee, Jung-Tae; Koh, Jeong-Tae; Jung, Hong-Moon; Lee, Heon-Jin; Kwon, Tae-Geon


    Stromal cell-derived factor-1 (SDF-1) protein and its receptor, CXCR-4, play an important role in tissue repair and regeneration in various organs, including the bone. SDF-1 is indispensable for bone morphogenetic protein-2 (BMP-2)-induced osteogenic differentiation. However, SDF-1 is not needed after the osteogenic induction has been activated. Since the precise condition for the additive effects of combined DF-1 and BMP-2 in bone healing had not been fully investigated, we aimed to determine the optimal conditions for SDF-1- and BMP-2-mediated bone regeneration. We examined the in vitro osteoblastic differentiation and cell migration after sequential treatments with SDF-1 and BMP-2. Based on the in vitro additive effects of SDF-1 and BMP-2, the critical size defects of mice calvaria were treated with these cytokines in various sequences. Phosphate buffered saline (PBS)-, SDF-1-, or BMP-2-soaked collagen scaffolds were implanted into the calvarial defects (n=36). Periodic percutaneous injections of PBS or the cytokine SDF-1 and BMP-2 into the implanted scaffolds were performed on days 3 and 6, postoperatively. Six experimental groups were used according to the types and sequences of the cytokine treatments. After 28 days, the mice were euthanized and bone formation was evaluated with microcomputed tomography and histology. The molecular mechanism of the additive effect of SDF-1 and BMP-2 was evaluated by analyzing intracellular signal transduction through Smad and Erk phosphorylation. The in vitro experiments revealed that, among all the treatments, the treatment with BMP-2 after SDF-1 showed the strongest osteoblastic differentiation and enhanced cell migration. Similarly, in the animal model, the treatment with SDF-1 followed by BMP-2 treatment showed the highest degree of new bone regeneration than any other groups, including the one with continuous BMP-2 treatment. This new bone formation can be partially explained by the activation of Smad and Erk pathways

  9. Towards reducing DBP formation potential of drinking water by favouring direct ozone over hydroxyl radical reactions during ozonation. (United States)

    De Vera, Glen Andrew; Stalter, Daniel; Gernjak, Wolfgang; Weinberg, Howard S; Keller, Jurg; Farré, Maria José


    When ozonation is employed in advanced water treatment plants to produce drinking water, dissolved organic matter reacts with ozone (O3) and/or hydroxyl radicals (OH) affecting disinfection byproduct (DBP) formation with subsequently used chlorine-based disinfectants. This study presents the effects of varying exposures of O3 and •OH on DBP concentrations and their associated toxicity generated after subsequent chlorination. DBP formation potential tests and in vitro bioassays were conducted after batch ozonation experiments of coagulated surface water with and without addition of tertiary butanol (t-BuOH, 10 mM) and hydrogen peroxide (H2O2, 1 mg/mg O3), and at different pH (6-8) and transferred ozone doses (0-1 mg/mg TOC). Although ozonation led to a 24-37% decrease in formation of total trihalomethanes, haloacetic acids, haloacetonitriles, and trihaloacetamides, an increase in formation of total trihalonitromethanes, chloral hydrate, and haloketones was observed. This effect however was less pronounced for samples ozonated at conditions favoring molecular ozone (e.g., pH 6 and in the presence of t-BuOH) over •OH reactions (e.g., pH 8 and in the presence of H2O2). Compared to ozonation only, addition of H2O2 consistently enhanced formation of all DBP groups (20-61%) except trihalonitromethanes. This proves that •OH-transformed organic matter is more susceptible to halogen incorporation. Analogously, adsorbable organic halogen (AOX) concentrations increased under conditions that favor •OH reactions. The ratio of unknown to known AOX, however, was greater at conditions that promote direct O3 reactions. Although significant correlation was found between AOX and genotoxicity with the p53 bioassay, toxicity tests using 4 in vitro bioassays showed relatively low absolute differences between various ozonation conditions.

  10. The formation and potential importance of cemented layers in inactive sulfide mine tailings (United States)

    Blowes, David W.; Reardon, Eric J.; Jambor, John L.; Cherry, John A.


    Investigations of inactive sulfide-rich tailings impoundments at the Heath Steele (New Brunswick) and Waite Amulet (Quebec) minesites have revealed two distinct types of cemented layers or "hardpans." That at Heath Steele is 10-15 cm thick, occurs 20-30 cm below the depth of active oxidation, is continuous throughout the tailings impoundment, and is characterized by cementation of tailings by gypsum and Fe(II) solid phases, principally melanterite. Hardpan at the Waite Amulet site is only 1-5 cm thick, is laterally discontinuous (10-100 cm), occurs at the depth of active oxidation, and is characterized by cementation of tailings by Fe(III) minerals, principally goethite, lepidocrocite, ferrihydrite, and jarosite. At Heath Steele, an accumulation of gas-phase CO 2, of up to 60% of the pore gas, occurs below the hardpan. The calculated diffusivity of the hardpan layer is only about 1/100 that of the overlying, uncemented tailings. The pore-water chemistry at Heath Steele has changed little over a 10-year period, suggesting that the cemented layer restricts the movement of dissolved metals through the tailings and also acts as a zone of metal accumulation. Generation of a cemented layer therefore has significant environmental and economic implications. It is likely that, in sulfide-rich tailings impoundments, the addition of carbonate-rich buffering material during the late stages of tailings deposition would enhance the formation of hardpan layers.

  11. Hydrate dissolution as a potential mechanism for pockmark formation in the Niger delta (United States)

    Sultan, N.; Marsset, B.; Ker, S.; Marsset, T.; Voisset, M.; Vernant, A. M.; Bayon, G.; Cauquil, E.; Adamy, J.; Colliat, J. L.; Drapeau, D.


    Based on acquired geophysical, geological and geotechnical data and modeling, we suggest hydrate dissolution to cause sediment collapse and pockmark formation in the Niger delta. Very high-resolution bathymetry data acquired from the Niger delta reveal the morphology of pockmarks with different shapes and sizes going from a small ring depression surrounding an irregular floor to more typical pockmarks with uniform depression. Geophysical data, in situ piezocone measurements, piezometer measurements and sediment cores demonstrate the presence of a common internal architecture of the studied pockmarks: inner sediments rich in gas hydrates surrounded by overpressured sediments. The temperature, pressure and salinity conditions of the studied area have allowed us to exclude the process of gas-hydrate dissociation (gas hydrate turns into free gas/water mixture) as a trigger of the observed pockmarks. Based on numerical modeling, we demonstrate that gas-hydrate dissolution (gas hydrate becomes mixture of water and dissolved gas) under a local decrease of the gas concentration at the base of the gas-hydrate occurrence zone (GHOZ) can explain the excess pore pressure and fluid flow surrounding the central hydrated area and the sediment collapse at the border of the GHOZ. The different deformation (or development) stages of the detected pockmarks confirm that a local process such as the amount of gas flow through faults rather than a regional one is at the origin of those depressions.

  12. Potential origin and formation for molecular components of humic acids in soils (United States)

    DiDonato, Nicole; Chen, Hongmei; Waggoner, Derek; Hatcher, Patrick G.


    Soil humic acids are the base soluble/acid insoluble organic components of soil organic matter. Most of what we know about humic acids comes from studies of their bulk molecular properties or analysis of individual fractions after extraction from soils. This work attempts to better define humic acids and explain similarities and differences for several soils varying in degrees of humification using advanced molecular level techniques. Our investigation using electrospray ionization coupled to Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS) and nuclear magnetic resonance spectroscopy (NMR) has given new insight into the distinctive molecular characteristics of humic acids which suggest a possible pathway for their formation. Humic acids from various ecosystems, climate regions and soil textural classes are distinguished by the presence of three predominant molecular components: lignin-like molecules, carboxyl-containing aliphatic molecules and condensed aromatic molecules that bear similarity to black carbon. Results show that humification may be linked to the relative abundance of these three types of molecules as well as the relative abundance of carboxyl groups in each molecular type. This work also demonstrates evidence for lignin as the primary source of soil organic matter, particularly condensed aromatic molecules often categorized as black carbon and is the first report of the non-pyrogenic source for these compounds in soils. We also suggest that much of the carboxyl-containing aliphatic molecules are sourced from lignin.

  13. The formation and potential importance of cemented layers in inactive sulfide mine tailings

    Energy Technology Data Exchange (ETDEWEB)

    Blowes, D.W.; Reardon, E.J.; Cherry, J.A. (Univ. of Waterloo, Ontario (Canada)); Jambor, J.L. (CANMET, Ontario (Canada))


    Investigations of inactive sulfide-rich tailings impoundments at the Heath Steele (New Brunswick) and Waite Amulet (Quebec) minesites have revealed two distinct types of cemented layers or hardpans. That at Heath Steele is 10-15 cm thick, occurs 20-30 cm below the depth of active oxidation, is continuous throughout the tailings impoundment, and is characterized by cementation of tailings by gypsum and Fe(II) solid phases, principally melanterite. Hardpan at the Waite Amulet site is only 1-5 cm thick, is laterally discontinuous (10-100 cm), occurs at the depth of active oxidation, and is characterized by cementation of tailings by Fe(III) minerals, principally goethite, lepidocrocite, ferrihydrite, and jarosite. At Heath Steele, an accumulation of gas-phase CO{sub 2}, of up to 60{percent} of the pore gas, occurs below the hardpan. The calculated diffusivity of the hardpan layer is only about 1/100 that of the overlying, uncemented tailings. The pore-water chemistry at Heath Steele has changed little over a 10-year period, suggesting that the cemented layer restricts the movement of dissolved metals through the tailings and also acts as a zone of metal accumulation. Generation of a cemented layer therefore has significant environmental and economic implications. It is likely that, in sulfide-rich tailings impoundments, the addition of carbonate-rich buffering material during the late stages of tailings deposition would enhance the formation of hardpan layers.

  14. Assessment of the Cluster Formation Potential in the Regions of the Southern Federal District

    Directory of Open Access Journals (Sweden)

    Svetlana Anatolyevna Beloglazova


    Full Text Available Cluster policy implementation is an important factor of economic development of a country as a whole as well as of a particular region. The clustering approach to regional development attaches high importance to the microeconomic sphere, as well as territorial and social aspects of economic development. Clusterization provides effective tools for stimulating socio-political and economic development of area, multiplying growth of employment and investment, accelerating advanced technologies transfer; wages increasing, budget revenues growing, and enhancing competitiveness of regional production systems. Analysis of the prerequisites, conditions and resources for the formation and development of innovation clusters becomes the foundation for the scientific justifying regional economy modernization strategy and creating its points of growth and innovative mode of developing. The analysis carried out on the basis of the author’s methodology, and on subsequent grouping and ranking of 4 regions of the Southern Federal District, including the Volgograd region, by clustering processes intensity criterion, made it possible to shape a view of strengths and weaknesses of the regional economies, and give recommendations to improve the environment for innovative clusters forming and functioning. The carried-out analysis gave the chance to define regions with optimum conditions for introduction of cluster policy and regions with possibility of cluster development which are at lower level both on separate indicators, and on composite indexes of initial and resultant indicators.

  15. Depositional environment and source potential of Jurassic coal-bearing sediments (Gresten Formation, Hoflein gas/condensate field, Austria)

    Energy Technology Data Exchange (ETDEWEB)

    Sachsenhofer, R.F.; Bechtel, A.; Kuffner, T.; Rainer, T.; Gratzer, R.; Sauer, R.; Sperl, H. [Mount University of Leoben, Leoben (Austria)


    Coal-bearing Jurassic sediments (Gresten Formation; Lower Quartzarenite Member) are discussed as source rocks for gas and minor oil in the basement of the Alpine-Carpathian frontal zone (e.g. Hoflein gas/condensate field). Core material has therefore been analysed to characterize depositional environment and source potential of the Lower Quartzarenite Member (LQM). Geochemical data from the Hoflein condensate are used to establish a Source-condensate correlation. The LQM was deposited in a flood basin with transitions to a delta-plain environment. Coal originated in frequently flooded mires and evolved within an oxygenated and acidic environment. It is inferred from geochemical data that organic matter from aquatic macrophytes and gymnosperms contributed to coal formation. Wildfires were abundant and oxidation of plant remains occurred frequently. This resulted in the formation of dull coal with very high inertinite contents. Bituminous shales were formed in deeper waters under dysoxic conditions. Apart from abundant algae and micro-organisms, it is concluded that there was an increased contribution of higher land plants relative to macrophytes to the biomass of the shales. Despite high inertinite contents, coal within the LQM has a significant oil potential. Bituminous shales contain a Type III-II kerogen. According to pyrolysis-gas chromatography data, coal and shale generate a high wax paraffinic oil. The organic matter is immature to marginal mature (0.55% Rr). Bituminous shales are considered a potential source for the Hoflein condensate. Coal may be the source for gas and minor oil in the Klement Field, but is not the source for the condensate.


    Directory of Open Access Journals (Sweden)

    I. Shaniukevich


    Full Text Available The paper considers a theme of typological urban housing diversity  which is relevant for a modern residential real estate market. Analyzed Quantitative and qualitative characteristics of the existing urban residential accommodation, new  house building have been analyzed in the paper. The paper presents author’s calculations of differentiation extent and changes in economic opportunities of the population. Differentiation of  potential consumer accommodation models with specific standardized characteristics has been made in terms of the population economic prosperity.  The paper substantiates proposals on accountability and implementation of typological differences in the government housing policy.

  17. Interatomic potential to study the formation of NiCr clusters in high Cr ferritic steels (United States)

    Bonny, G.; Bakaev, A.; Olsson, P.; Domain, C.; Zhurkin, E. E.; Posselt, M.


    Under irradiation NiSiPCr clusters are formed in high-Cr ferritic martensitic steels as well as in FeCr model alloys. In the literature little is known about the origin and contribution to the hardening of these clusters. In this work we performed density functional theory (DFT) calculations to study the stability of small substitutional NiCr-vacancy clusters and interstitial configurations in bcc Fe. Based on DFT data and experimental considerations a ternary potential for the ferritic FeNiCr system was developed. The potential was applied to study the thermodynamic stability of NiCr clusters by means of Metropolis Monte Carlo (MMC) simulations. The results of our simulations show that Cr and Ni precipitate as separate fractions and suggest only a limited synergetic effect between Ni and Cr. Therefore our results suggest that the NiCrSiP clusters observed in experiments must be the result of other mechanisms than the synergy of Cr and Ni at thermal equilibrium.


    Directory of Open Access Journals (Sweden)

    I. A. Panteleev


    transition is manifested by localized cataclastic deformation (i.e. a set of weak earthquakes, which migrates in space at a velocity several orders of magnitude lower than the speed of sound, as a ‘slow’ deformation wave (Fig. 3. Further reduction of the structural scaling parameter leads to degeneracy of the orientation meta-stability and formation of localized dissipative defect structures in the medium. Once the critical stress is reached, such structures develop in the blow-up regime, i.e. the mode of avalanche-unstable growth of defects in the localized area that is shrinking eventually. At the scale of observation, this process is manifested as brittle fracturing that causes formation of a deformation zone, which size is proportional to the scale of observation, and corresponds to occurrence of a strong earthquake.On the basis of the proposed model showing the behavior of the geomedium containing defects in the field of external stresses, it is possible to describe main ways of stress relaxation in the rock massives – brittle large-scale destruction and cataclastic deformation as consequences of the collective behavior of defects, which is determined by the structural scaling parameter.Results of this study may prove useful for estimation of critical stresses and assessment of the geomedium status in seismically active regions and be viewed as model representations of the physical hypothesis about the uniform nature of deve­lopment of discontinuities/defects in a wide range of spatial scales. 

  19. The potential role of salt abuse on the risk for kidney stone formation (United States)

    Sakhaee, K.; Harvey, J. A.; Padalino, P. K.; Whitson, P.; Pak, C. Y.


    The kidney stone-forming risk of a high sodium diet was evaluated by assessing the effect of such a diet on the crystallization of stone-forming salts in urine. Fourteen normal subjects participated in 2 phases of study of 10 days duration each, comprising a low sodium phase (basal metabolic diet containing 50 mmol. sodium per day) and a high sodium phase (basal diet plus 250 mmol. sodium chloride per day). The high sodium intake significantly increased urinary sodium (34 +/- 12 to 267 +/- 56 mmol. per day), calcium (2.73 +/- 1.03 to 3.93 +/- 1.51 mmol. per day) and pH (5.79 +/- 0.44 to 6.15 +/- 0.25), and significantly decreased urinary citrate (3.14 +/- 1.19 to 2.52 +/- 0.83 mmol. per day). Arterialized venous blood bicarbonate and total serum carbon dioxide concentrations decreased significantly during the high sodium diet, whereas serum chloride concentration increased. However, no change in arterialized venous pH was detected. Thus, a high sodium intake not only increased calcium excretion, but also increased urinary pH and decreased citrate excretion. The latter effects are probably due to sodium-induced bicarbonaturia and a significant decrease in serum bicarbonate concentration, respectively. Commensurate with these changes, the urinary saturation of calcium phosphate (brushite) and monosodium urate increased, and the inhibitor activity against calcium oxalate crystallization (formation product) decreased. The net effect of a high sodium diet was an increased propensity for the crystallization of calcium salts in urine.

  20. Meeting the Needs of Sexual and Gender Minority Youth: Formative Research on Potential Digital Health Interventions. (United States)

    Steinke, Jessica; Root-Bowman, Meredith; Estabrook, Sherry; Levine, Deborah S; Kantor, Leslie M


    Sexual and gender minority youth (SGMY) have unique risk factors and worse health outcomes than their heterosexual and cisgender counterparts. SGMY's significant online activity represents an opportunity for digital interventions. To help meet the sex education and health needs of SGMY and to understand what they consider important, formative research was conducted to guide and inform the development of new digital health interventions. Semistructured interviews, in-person focus groups, and online focus groups were conducted with 92 youths (aged 15-19 years) who self-identify as nonheterosexual, noncisgender, questioning, and/or have engaged in same-sex sexual behavior. Data were coded and analyzed using inductive thematic analysis. Thematic analysis revealed that SGMYs are often driven online by experiences of isolation, stigmatization, and lack of information and are looking for a supportive, validating community and relevant, accurate information. Gender minority youths felt that they faced a larger number of and more extreme incidences of discrimination than sexual minority youths. Most youths described interpersonal discrimination as having substantial negative effects on their mental health. Any digital intervention for SGMY should focus on mental health and well-being holistically rather than solely on risk behaviors, such as preventing HIV. Interventions should include opportunities for interpersonal connection, foster a sense of belonging, and provide accurate information about sexuality and gender to help facilitate positive identity development. Content and delivery of digital interventions should appeal to diverse sexualities, genders, and other intersecting identities held by SGMY to avoid further alienation. Copyright © 2016 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  1. Arbuscular mycorrhizal fungi (AMF on a sandbank plant formation: ecology and potential for hydrocarbon oil mycorrhizoremediation

    Directory of Open Access Journals (Sweden)

    Ocimar Ferreira de Andrade


    Full Text Available The sources of contamination related to the exploration, production, storage, transport, distribution and disposal of petroleum, and its products, carry risks that threaten fragile coastal environments, little studied and, thus, in need of attention from the scientific community. On the other hand, symbiont mechanisms essential for the very existence of many plant species, and their relation to contaminated soils, remain unknown. Despite the identification of several species of AMF halophytes soil communities in sandbanks, one can infer their bioremediation potential from studies in other types of soil, which, however, report the same genera of fungi as participants in mycorrhizoremediation processes of polluted soil. This study focuses on the application of biotechnology using Arbuscular Mycorrhizal Fungi (AMF in soils impacted by petroleum hydrocarbons.

  2. Variation of the input resistance and membrane potential of a neuron in trace formation. (United States)

    D'yakonova, T L; Mikhal'tsev, I E


    Trace changes in electrical activity, input resistance (Rinp), and membrane potential (MP) of brain neurons are studied in the mollusk Limnaea stagnalis for intracellular stimulation with a sinusoidal threshold current with a frequency of 0.1 Hz during 20 min. Some neurons are shown to exhibit an effect of facilitation, a rise in the level of activity being attending by an increase in Rinp and depolarization. Other neurons displayed lowered activity with a decrease of Rinp and hyperpolarization. The selectivity of the Rinp variations relative to the parameters of the stimuli (maximum changes at the frequency of the current used) suggests that it is precisely trace changes of Rinp which lie at the basis of the neuronal plasticity in "learning." Some neurons in this series of experiments did not alter their electrical response, Rinp, or MP for stimulation. The possible reason for the non-uniform reaction of different neurons to identical stimulation is discussed.

  3. Prediction of nucleosome DNA formation potential and nucleosome positioning using increment of diversity combined with quadratic discriminant analysis. (United States)

    Zhao, Xiujuan; Pei, Zhiyong; Liu, Jia; Qin, Sheng; Cai, Lu


    In this work, a novel method was developed to distinguish nucleosome DNA and linker DNA based on increment of diversity combined with quadratic discriminant analysis (IDQD), using k-mer frequency of nucleotides in genome. When used to predict DNA potential for forming nucleosomes, the model achieved a high accuracy of 94.94%, 77.60%, and 86.81%, respectively, for Saccharomyces cerevisiae, Homo sapiens, and Drosophila melanogaster. The area under the receiver operator characteristics curve of our classifier was 0.982 for S. cerevisiae. Our results indicate that DNA sequence preference is critical for nucleosome formation potential and is likely conserved across eukaryotes. The model successfully identified nucleosome-enriched or nucleosome-depleted regions in S. cerevisiae genome, suggesting nucleosome positioning depends on DNA sequence preference. Thus, IDQD classifier is useful for predicting nucleosome positioning.

  4. A new parametrization for ambient particle formation over coniferous forests and its potential implications for the future

    Directory of Open Access Journals (Sweden)

    B. Bonn


    Full Text Available Atmospheric new particle formation is a general phenomenon observed over coniferous forests. So far nucleation is either parameterised as a function of gaseous sulphuric acid concentration only, which is unable to explain the observed seasonality of nucleation events at different measurement sites, or as a function of sulphuric acid and organic molecules. Here we introduce different nucleation parameters based on the interaction of sulphuric acid and terpene oxidation products and elucidate the individual importance. They include basic trace gas and meteorological measurements such as ozone and water vapour concentrations, temperature (for terpene emission and UV B radiation as a proxy for OH radical formation. We apply these new parameters to field studies conducted at conducted at Finnish and German measurement sites and compare these to nucleation observations on a daily and annual scale. General agreement was found, although the specific compounds responsible for the nucleation process remain speculative. This can be interpreted as follows: During cooler seasons the emission of biogenic terpenes and the OH availability limits the new particle formation while towards warmer seasons the ratio of ozone and water vapour concentration seems to dominate the general behaviour. Therefore, organics seem to support ambient nucleation besides sulphuric acid or an OH-related compound. Using these nucleation parameters to extrapolate the current conditions to prognosed future concentrations of ozone, water vapour and organic concentrations leads to a significant potential increase in the nucleation event number.

  5. Matrix metalloproteinases regulate the formation of dendritic spine head protrusions during chemically induced long-term potentiation.

    Directory of Open Access Journals (Sweden)

    Zsuzsanna Szepesi

    Full Text Available Dendritic spines are are small membranous protrusions that extend from neuronal dendrites and harbor the majority of excitatory synapses. Increasing evidence has shown that matrix metalloproteinases (MMPs, a family of extracellularly acting and Zn(2+-dependent endopeptidases, are able to rapidly modulate dendritic spine morphology. Spine head protrusions (SHPs are filopodia-like processes that extend from the dendritic spine head, representing a form of postsynaptic structural remodeling in response to altered neuronal activity. Herein, we show that chemically induced long-term potentiation (cLTP in dissociated hippocampal cultures upregulates MMP-9 activity that controls the formation of SHPs. Blocking of MMPs activity or microtubule dynamics abolishes the emergence of SHPs. In addition, autoactive recombinant MMP-9, promotes the formation of SHPs in organotypic hippocampal slices. Furthermore, spines with SHPs gained postsynaptic α-amino-3-hydroxyl-5-methyl-4-isoxazole propionic acid (AMPA receptors upon cLTP and the synaptic delivery of AMPA receptors was controlled by MMPs. The present results strongly imply that MMP-9 is functionally involved in the formation of SHPs and the control of postsynaptic receptor distribution upon cLTP.

  6. Characterization of dissolved organic matter for prediction of trihalomethane formation potential in surface and sub-surface waters. (United States)

    Awad, John; van Leeuwen, John; Chow, Christopher; Drikas, Mary; Smernik, Ronald J; Chittleborough, David J; Bestland, Erick


    Dissolved organic matter (DOM) in surface waters used for drinking purposes can vary markedly in character dependent on their sources within catchments. The character of DOM further influences the formation of disinfection by products when precursor DOM present in drinking water reacts with chlorine during disinfection. Here we report the development of models that describe the formation potential of trihalomethanes (THMFP) dependent on the character of DOM in waters from discrete catchments with specific land-use and soil textures. DOM was characterized based on UV absorbance at 254 nm, apparent molecular weight and relative abundances of protein-like and humic-like compounds. DOM character and Br concentration (up to 0.5 mg/L) were used as variables in models (R(2)>0.93) of THMFP, which ranged from 19 to 649 μg/L. Chloroform concentration (12-594 μg/L) and relative abundance (27-99%) were first modeled (R(2)>0.85) and from these, the abundances of bromodichloromethane and chlorodibromomethane estimated using power and exponential functions, respectively (R(2)>0.98). From these, the abundance of bromoform is calculated. The proposed model may be used in risk assessment of catchment factors on formation of trihalomethanes in drinking water, in context of treatment efficiency for removal of organic matter.

  7. The Galactic Center Cloud G0.253+0.016: A Massive Dense Cloud with low Star Formation Potential

    CERN Document Server

    Kauffmann, Jens; Zhang, Qizhou


    We present the first interferometric molecular line and dust emission maps for the Galactic Center (GC) cloud G0.253+0.016, observed using the Combined Array for Research in Millimeter--wave Astronomy (CARMA) and the Submillimeter Array (SMA). This cloud is very dense, and concentrates a mass exceeding the Orion Molecular Cloud Complex (2x10^5 M_sun) into a radius of only 3pc, but it is essentially starless. G0.253+0.016 therefore violates "star formation laws" presently used to explain trends in galactic and extragalactic star formation by a factor ~45. Our observations show a lack of dense cores of significant mass and density, thus explaining the low star formation activity. Instead, cores with low densities and line widths 1km/s---probably the narrowest lines reported for the GC region to date---are found. Evolution over several 10^5 yr is needed before more massive cores, and possibly an Arches--like stellar cluster, could form. Given the disruptive dynamics of the GC region, and the potentially unbound ...

  8. A new occurrence of ambient inclusion trails from the ~1900-million-year-old Gunflint Formation, Ontario: nanocharacterization and testing of potential formation mechanisms. (United States)

    Wacey, D; Saunders, M; Kong, C; Kilburn, M R


    Ambient inclusion trails (AITs) are tubular microstructures thought to form when a microscopic mineral crystal is propelled through a fine-grained rock matrix. Here, we report a new occurrence of AITs from a fossilized microbial mat within the 1878-Ma Gunflint Formation, at Current River, Ontario. The AITs are 1-15 μm in diameter, have pyrite as the propelled crystal, are infilled with chlorite and have been propelled through a microquartz (chert) or chlorite matrix. AITs most commonly originate at the boundary between pyrite- and chlorite-rich laminae and chert-filled fenestrae, with pyrite crystals propelled into the fenestrae. A subset of AITs originate within the fenestrae, rooted either within the chert or within patches of chlorite. Sulphur isotope data ((34) S/(32) S) obtained in situ from AIT pyrite have a δ(34) S of -8.5 to +8.0 ‰, indicating a maximum of ~30 ‰ fractionation from Palaeoproterozoic seawater sulphate (δ(34) S ≈ +20 ‰). Organic carbon is common both at the outer margins of the fenestrae and in patches of chlorite where most AITs originate, and can be found in smaller quantities further along some AITs towards the terminal pyrite grain. We infer that pyrite crystals now found within the AITs formed via the action of heterotrophic sulphate-reducing bacteria during early diagenesis within the microbial mat, as pore waters were becoming depleted in seawater sulphate. Gases derived from this process such as CO2 and H2 S were partially trapped within the microbial mat, helping produce birds-eye fenestrae, while rapid microquartz precipitation closed porosity. We propose that propulsion of the pyrite crystals to form AITs was driven by two complementary mechanisms during burial and low-grade metamorphism: firstly, thermal decomposition of residual organic material providing CO2 , and potentially CH4 , as propulsive gases, plus organic acids to locally dissolve the microquartz matrix; and secondly, reactions involving clay minerals that

  9. Comparative evaluation of particle properties, formation of reactive oxygen species and genotoxic potential of tungsten carbide based nanoparticles in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Kuehnel, Dana, E-mail: [Department of Bioanalytical Ecotoxicology, Helmholtz-Centre for Environmental Research Leipzig - UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Scheffler, Katja [Department of Bioanalytical Ecotoxicology, Helmholtz-Centre for Environmental Research Leipzig - UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Department of Cell Techniques and Applied Stem Cell Biology, University of Leipzig, Deutscher Platz 5, 04103 Leipzig (Germany); Wellner, Peggy [Department of Bioanalytical Ecotoxicology, Helmholtz-Centre for Environmental Research Leipzig - UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Meissner, Tobias; Potthoff, Annegret [Fraunhofer-Institute for Ceramic Technologies and Systems (IKTS), Winterbergstr. 28, 01277 Dresden (Germany); Busch, Wibke [Department of Bioanalytical Ecotoxicology, Helmholtz-Centre for Environmental Research Leipzig - UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Springer, Armin [Centre for Translational Bone, Cartilage and Soft Tissue Research, University Hospital Carl Gustav Carus, Technical University Dresden, Fetscherstrasse 74, 01307 Dresden (Germany); Schirmer, Kristin [Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Duebendorf (Switzerland); EPF Lausanne, School of Architecture, Civil and Environmental Engineering, 1015 Lausanne (Switzerland); ETH Zuerich, Institute of Biogeochemistry and Pollutant Dynamics, 8092 Zuerich (Switzerland)


    Highlights: Black-Right-Pointing-Pointer Assessment of toxic potential of tungsten carbide-based nanoparticles. Black-Right-Pointing-Pointer Evaluation of ROS and micronuclei induction of three hard metal nanomaterials. Black-Right-Pointing-Pointer Dependency of observed toxic effects on the materials physical-chemical properties. Black-Right-Pointing-Pointer Differences in several particle properties seem to modulate the biological response. - Abstract: Tungsten carbide (WC) and cobalt (Co) are constituents of hard metals and are used for the production of extremely hard tools. Previous studies have identified greater cytotoxic potential of WC-based nanoparticles if particles contained Co. The aim of this study was to investigate whether the formation of reactive oxygen species (ROS) and micronuclei would help explain the impact on cultured mammalian cells by three different tungsten-based nanoparticles (WC{sub S}, WC{sub L}, WC{sub L}-Co (S: small; L: large)). The selection of particles allowed us to study the influence of particle properties, e.g. surface area, and the presence of Co on the toxicological results. WC{sub S} and WC{sub L}/WC{sub L}-Co differed in their crystalline structure and surface area, whereas WC{sub S}/WC{sub L} and WC{sub L}-Co differed in their cobalt content. WC{sub L} and WC{sub L}-Co showed neither a genotoxic potential nor ROS induction. Contrary to that, WC{sub S} nanoparticles induced the formation of both ROS and micronuclei. CoCl{sub 2} was tested in relevant concentrations and induced no ROS formation, but increased the rate of micronuclei at concentrations exceeding those present in WC{sub L}-Co. In conclusion, ROS and micronuclei formation could not be associated with the presence of Co in the WC-based particles. The contrasting responses elicited by WC{sub S} vs. WC{sub L} appear to be due to large differences in crystalline structure.


    Directory of Open Access Journals (Sweden)

    João Flávio Costa dos Santos

    Full Text Available ABSTRACT In Brazil, the remaining areas of Atlantic Forest are intensely fragmented. The connection of forest fragments through ecological corridors is an important step in biodiversity conservation. Certain areas are more resilient, and in those areas, natural forest regeneration, for example, can be encouraged. The aim of this study was to identify areas of greater resilience in order to support the connection of Atlantic Forest fragments with ecological corridors. Forest fragments in the municipality of Paraíba do Sul, in the state of Rio de Janeiro, were mapped using the supervised maximum likelihood classification of an Operational Land Imager (OLI/Landsat-8 sensor image. Next, we analyzed the influence of terrain attributes (aspect, incident solar radiation, slope, and curvature profile on natural regeneration. The areas with the greatest potential to achieve natural regeneration and to form ecological corridors were indicated through fuzzy membership functions. Within Paraíba do Sul, 31% of the territory is covered by vegetation in different stages of regeneration. Recordings were made of 1,251 forest fragments in a middle or advanced stage of regeneration. These fragments are usually situated in the southeast, south, and southwest aspects, in areas that receive the least amount of global solar radiation (Wh·m-2 per year, and on slopes with an angle of inclination greater than 20%. The adjustment of fuzzy functions identified 17,327.5 ha with a tendency to recover, and which are therefore strategic areas in the development of ecological corridors.

  11. Evaluation of Potential Effects of NaCl and Sorbic Acid on Staphylococcal Enterotoxin A Formation

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    Nikoleta Zeaki


    Full Text Available The prophage-encoded staphylococcal enterotoxin A (SEA is recognized as the main cause of staphylococcal food poisoning (SFP, a common foodborne intoxication disease, caused by Staphylococcus aureus. Studies on the production of SEA suggest that activation of the SOS response and subsequent prophage induction affect the regulation of the sea gene and the SEA produced, increasing the risk for SFP. The present study aims to evaluate the effect of NaCl and sorbic acid, in concentrations relevant to food production, on SOS response activation, prophage induction and SEA production. The impact of stress was initially evaluated on steady state cells for a homogenous cell response. NaCl 2% was found to activate the SOS response, i.e., recA expression, and trigger prophage induction, in a similar way as the phage-inducer mitomycin C. In contrast, sorbic acid decreased the pH of the culture to a level where prophage induction was probably suppressed, even when combined with NaCl stress. The impact of previous physiological state of the bacteria was also addressed on cells pre-exposed to NaCl, and was found to potentially affect cell response upon exposure to further stress. The results obtained highlight the possible SFP-related risks arising from the use of preservatives during food processing.


    Directory of Open Access Journals (Sweden)

    A. Yu. Bekkiev


    Full Text Available The article deals with the problem of the system to strengthen the defense industrial capacity. Explored approaches to this problem, given that domestic authors investigated the prospects of high-tech enterprise innovation systems and their sustainability, as well as a variety of instructional approaches, foreign authors assign great importance to the strategic management and systems analysis Management by Objectives defense complex. The problems of strengthening the military-industrial complex and their solutions are presented, such as the need to improve strategic planning (scenario variability of plans, co-ordinated action to overcome threats, challenges and risks, scientific and methodological rationale for the decision-making at all levels (national, regional and organizational. The author gives a system to strengthen the military-industrial potential in the concept of national security, which includes: national values, the program of socio-economic development of the Russian Federation, foreign policy concept, the concept of strengthening the military-industrial complex in Russia's national security, the program of socio-economic development of the Voronezh region, as well as methods of analysis and strengthening the military-industrial complex. Particular attention is paid to the method of co-financing of defense enterprises and methods of quantifying the performance objectives semistructured systems.

  13. Formation of competitive potential of the machine-building complex of the region

    Directory of Open Access Journals (Sweden)

    Oleg Ivanovich Botkin


    Full Text Available The article describes the features of competitive potential of regional machine-building complex in a globalized world economy. The purpose of the research is the development of theoretically reasonable economic basis of the machine-building complex considering  the  features of business in the conditions of the WTO. In the work, the hypothesis of a special role of the external economic factors locates in development of the enterprises of regional industrial complexes. The study of the theoretical provisions defining the development of the region revealed the factors determining influence of the international trade agreements on spatial localization of the industry. The main attention is paid to an analytical assessment of the current state and the trends, which have developed in the period of post-crisis economic recovery. Analysis of the main indicators of attractiveness has revealed the weak position of local industrial enterprises in the WTO. The directions of strengthening of the competitive capacity of the local industrial enterprises are defined. The obtained results allow us to increase the sustainability of the industry by means of effective management mechanism improvements and to create favorable operating conditions of a machine-building complex of the region

  14. Characterization of Green Liquor Dregs, Potentially Useful for Prevention of the Formation of Acid Rock Drainage

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    Maria Mäkitalo


    Full Text Available Using alternative materials such as residual products from other industries to mitigate the negative effects of acid rock drainage would simultaneously solve two environmental problems. The main residual product still landfilled by sulphate paper mills is the alkaline material green liquor dregs (GLD. A physical, mineralogical and chemical characterization of four batches of GLD was carried out to evaluate the potential to use it as a sealing layer in the construction of dry covers on sulphide-bearing mine waste. GLD has relatively low hydraulic conductivity (10−8 to 10−9 m/s, a high water retention capacity (WRC and small particle size. Whilst the chemical and mineralogical composition varied between the different batches, these variations were not reflected in properties such as hydraulic conductivity and WRC. Due to relatively low trace element concentrations, leaching of contaminants from the GLD is not a concern for the environment. However, GLD is a sticky material, difficult to apply on mine waste deposits and the shear strength is insufficient for engineering applications. Therefore, improving the mechanical properties is necessary. In addition, GLD has a high buffering capacity indicating that it could act as an alkaline barrier. Once engineering technicalities have been overcome, the long-term effectiveness of GLD should be studied, especially the effect of aging and how the sealing layer would be engineered in respect to topography and climatic conditions.

  15. Study of the Effects of Total Flavonoids of Astragalus on Atherosclerosis Formation and Potential Mechanisms

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    Deqing Wang


    Full Text Available Astragalus mongholicus Bunge has long been used to treat cardiovascular disease in Chinese traditional medicine. However, its mechanisms are not fully understood. In this study, we explored potential mechanisms and protective effects of total flavonoids of Astragalus (TFA on cardiovascular disease using in vitro experiments and diet-induced atherosclerotic rabbits. We identified six components and their proportion in TFA. The animal experiments showed that TFA significantly reduced plasma levels of total cholesterol and LDL cholesterol (P<0.05 to 0.01, increased HDL cholesterol levels (P<0.01, and reduced the aortic fatty streak area by 43.6 to 63.6% (P<0.01. We also found that TFA scavenged superoxide and hydroxyl radicals and this effect increased with higher TFA concentration. In in vivo experiments, TFA effectively inhibited the free radical spectrum in the ischemia-reperfusion module. In conclusion, TFA was the active component of Astragalus mongholicus Bunge, which benefits cardiovascular disease attributing to the potent antioxidant activity to improve the atherosclerosis profile.

  16. Application of Discriminant Analysis for Studying the Source Rock Potential of Probable Formations in the Lorestan Basin, Iran

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    Amir Negahdari


    Full Text Available Understanding the performance and role of each formation in a petroleum play is crucial for the efficient and precise exploration and exploitation of trapped hydrocarbons in a sedimentary basin. The Lorestan basin is one of the most important hydrocarbon basins of Iran, and it includes various oil-prone potential source rocks and reservoir rocks. Previous geochemical studies of the basin were not accurate and there remain various uncertainties about the potential of the probable source rocks of the basin. In the present research, the geochemical characteristics of four probable source rocks of the Lorestan basin are studied using Rock-Eval pyrolysis and discriminant analysis. In achieving this goal, several discriminant functions are defined to evaluate the discriminant factor for the division of samples into two groups. The function with the highest discriminant factor was selected for the classification of probable source rocks into two groups: weak and strong. Among the studied formations, Garau and Pabdeh had the richest and poorest source rocks of the Lorestan basin, respectively. The comparison of the obtained results with the previous literature shows that the proposed model is more reliable for the recognition of the richness of source rock in the area.

  17. TiO2 photocatalysis of natural organic matter in surface water: impact on trihalomethane and haloacetic acid formation potential. (United States)

    Liu, Sanly; Lim, May; Fabris, Rolando; Chow, Christopher; Drikas, Mary; Amal, Rose


    In this study, changes in the physical and structural properties of natural organic matter (NOM) during titanium dioxide photocatalytic oxidation process were investigated using several complementary analytical techniques. Potential of the treated water to form trihalomethanes (THMs) and haloacetic acids (HAAs) was also studied. High-performance size exclusion chromatography analysis showed that NOM with apparent molecular weights of 1-4 kDa were preferentially degraded, leading to the formation of lower molecular weight organic compounds. Resin fractionation of the treated water demonstrated that the photocatalytic oxidation changed the affinity of the bulk organic character from predominantly hydrophobic to more hydrophilic. Short chain aldehydes and ketones were identified by mass spectroscopy as one of the key degradation products. The addition of hydrogen peroxide to photocatalysis was found to increase the degradation kinetics but did not affect the reaction pathway, thus producing similar degradation end products. The amount of THMs normalized per dissolved organic carbon (specific THM) formed upon chlorination of NOM treated with photocatalytic oxidation was reduced from 56 to 10 microg/mg. In contrast, the specific HAAs formation potential of the treated water remained relatively unchanged from the initial value of 38 microg/mg, which could be due to the presence of hydrophilic precursor compounds that were formed as a result of the photocatalytic oxidation process.

  18. The gas formation potential of forage and cereal crops in biogas production; Das Gasbildungspotenzial von Halm- und Koernerfruechten bei der Biogasgewinnung

    Energy Technology Data Exchange (ETDEWEB)

    Weissbach, Friedrich


    The biogas yield depends on the gas formation potential of the substrates used and on the degree of exploiting this potential by the fermentation technology. Subject of assessing substrates can therefore only be the gas formation potential, independent from the fermentation technology. For assessing this gas formation potential of harvested crops and the silages produced from them a new parameter is suggested, which is the ''content of fermentable organic matter'' (FOM, in German language PoTS). This parameter can be estimated from the results of relatively simple laboratory analyses. For calculating the gas formation potential of all forage and cereal crops, 420 litres methane in 800 litres biogas per kg FOM can be assumed generally. In sugar beet a special assessment is needed. (orig.)

  19. Assessment of Gas Potential in the Niobrara Formation, Rosebud Reservation, South Dakota

    Energy Technology Data Exchange (ETDEWEB)

    Harris, Aubrey E. [West Virginia Univ., Morgantown, WV (United States); National Energy Technology Lab. (NETL), Morgantown, WV (United States); U.S. Bureau of Reclamation, Albuquerque, NM (United States); Hopkinson, Leslie [West Virginia Univ., Morgantown, WV (United States); Soeder, Daniel [National Energy Technology Lab. (NETL), Morgantown, WV (United States)


    Surface water and groundwater risks associated with unconventional oil and gas development result from potential spills of the large volumes of chemicals stored on-site during drilling and hydraulic fracturing operations, and the return to the surface of significant quantities of saline water produced during oil or gas well production. To better identify and mitigate risks, watershed models and tools are needed to evaluate the dispersion of pollutants in possible spill scenarios. This information may be used to determine the placement of in-stream water-quality monitoring instruments and to develop early-warning systems and emergency plans. A chemical dispersion model has been used to estimate the contaminant signal for in-stream measurements. Spills associated with oil and gas operations were identified within the Susquehanna River Basin Commission’s Remote Water Quality Monitoring Network. The volume of some contaminants was found to be sufficient to affect the water quality of certain drainage areas. The most commonly spilled compounds and expected peak concentrations at monitoring stations were used in laboratory experiments to determine if a signal could be detected and positively identified using standard water-quality monitoring equipment. The results were compared to historical data and baseline observations of water quality parameters, and showed that the chemicals tested do commonly affect water quality parameters. This work is an effort to demonstrate that hydrologic and water quality models may be applied to improve the placement of in-stream water quality monitoring devices. This information may increase the capability of early-warning systems to alert community health and environmental agencies of surface water spills associated with unconventional oil and gas operations.

  20. Volcanic settings and their reservoir potential: An outcrop analog study on the Miocene Tepoztlán Formation, Central Mexico (United States)

    Lenhardt, Nils; Götz, Annette E.


    The reservoir potential of volcanic and associated sedimentary rocks is less documented in regard to groundwater resources, and oil and gas storage compared to siliciclastic and carbonate systems. Outcrop analog studies within a volcanic setting enable to identify spatio-temporal architectural elements and geometric features of different rock units and their petrophysical properties such as porosity and permeability, which are important information for reservoir characterization. Despite the wide distribution of volcanic rocks in Mexico, their reservoir potential has been little studied in the past. In the Valley of Mexico, situated 4000 m above the Neogene volcanic rocks, groundwater is a matter of major importance as more than 20 million people and 42% of the industrial capacity of the Mexican nation depend on it for most of their water supply. Here, we present porosity and permeability data of 108 rock samples representing five different lithofacies types of the Miocene Tepoztlán Formation. This 800 m thick formation mainly consists of pyroclastic rocks, mass flow and fluvial deposits and is part of the southern Transmexican Volcanic Belt, cropping out south of the Valley of Mexico and within the two states of Morelos and Mexico State. Porosities range from 1.4% to 56.7%; average porosity is 24.8%. Generally, permeabilities are low to median (0.2-933.3 mD) with an average permeability of 88.5 mD. The lavas are characterized by the highest porosity values followed by tuffs, conglomerates, sandstones and tuffaceous breccias. On the contrary, the highest permeabilities can be found in the conglomerates, followed by tuffs, tuffaceous breccias, sandstones and lavas. The knowledge of these petrophysical rock properties provides important information on the reservoir potential of volcanic settings to be integrated to 3D subsurface models.

  1. Behavioral and physiological changes during benthic-pelagic transition in the harmful alga, Heterosigma akashiwo: potential for rapid bloom formation.

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    Elizabeth D Tobin

    Full Text Available Many species of harmful algae transition between a motile, vegetative stage in the water column and a non-motile, resting stage in the sediments. Physiological and behavioral traits expressed during benthic-pelagic transition potentially regulate the timing, location and persistence of blooms. The roles of key physiological and behavioral traits involved in resting cell emergence and bloom formation were examined in two geographically distinct strains of the harmful alga, Heterosigma akashiwo. Physiological measures of cell viability, division and population growth, and cell fatty acid content were made using flow cytometry and gas chromatography - mass spectrometry techniques as cells transitioned between the benthic resting stage and the vegetative pelagic stage. Video-based tracking was used to quantify cell-level swimming behaviors. Data show increased temperature and light triggered rapid emergence from the resting stage and initiated cell swimming. Algal strains varied in important physiological and behavioral traits, including survivorship during life-stage transitions, population growth rates and swimming velocities. Collectively, these traits function as "population growth strategies" that can influence bloom formation. Many resting cells regained the up-swimming capacity necessary to cross an environmentally relevant halocline and the ability to aggregate in near-surface waters within hours after vegetative growth supporting conditions were restored. Using a heuristic model, we illustrate how strain-specific population growth strategies can govern the timescales over which H. akashiwo blooms form. Our findings highlight the need for identification and quantification of strain-specific physiological and behavioral traits to improve mechanistic understanding of bloom formation and successful bloom prediction.

  2. Carbonate Geochemistry of Marine Authigenic Carbonates and Host Sediments: Exploring Mineral Formation Pathways and Organic Preservation Potential in Modern Sediments (United States)

    Smirnoff, M. N.; Loyd, S. J.


    Ancient authigenic dolomites (e.g., concretions) have been long studied in order to determine formation conditions and provide insight into shallow diagenetic environments. The formation of these dolomites is commonly attributed to the anaerobic microbial degradation of organic matter (a process that can increase the local pore water alkalinity), based on carbon isotope as well as other geochemical data. Authigenic dolomites also occur in modern, "still soft" sediments rich in organic matter. However, a comprehensive carbon isotopic characterization of these precipitates has yet to be conducted. Preliminary data show a wide range of δ13C values (about -11 to +12‰). Positive values that typify dolomites of the Gulf of California and the southwestern African margin indicate methanogenesis. Dolomites of the Peru margin and Cariaco Basin yield negative values that may represent a variety of organic matter degradation mechanisms. Regardless of specific mechanisms, organic matter degradation can promote authigenesis. Ultimately, mineralization encases primary sedimentary components and may act to preserve organic matter from subsequent degradation due to permeability reduction resulting from cementation. Concretionary carbonates have been found to preserve macro and micro fossils, metastable sedimentary grains, magnetic minerals, sedimentary structures, various specific organic compounds, and overmature organic matter exposed in outcrop. However, a similar protective relationship has not been demonstrated for disseminated, bulk organic matter in still-soft sediments. The study of these sediments 1) reveal the relationship between organic carbon degradation and authigenesis and 2) may provide insight into the potential of cementation to preserve organic matter during subsequent burial.

  3. Autoinducer-2-like activity on vegetable produce and its potential involvement in bacterial biofilm formation on tomatoes. (United States)

    Lu, Lingeng; Hume, Michael E; Pillai, Suresh D


    Quorum sensing employing autoinducer molecules is a strategy used by bacterial populations to coordinately modulate their response to environmental stresses and host defense mechanisms. The objectives of this study were to determine the levels of autoinducer-2 (AI-2)-like activity on selected vegetable produce and determine whether AI-2-like molecules can promote E. coli O157:H7 biofilm formation on tomatoes. Twelve different fruit and vegetable produce samples were screened for AI-2-like activity using autoinducer sensing V. harveyi biosensor strains. All samples except strawberries showed AI-2 activity albeit at varying levels, with eggplant having the highest levels. Tomatoes, when stored at 4 degrees C for 9 days, showed increasing levels of heterotrophic bacterial populations as compared to AI-2-like activity levels, which fluctuated. Rinses from Roma tomato surfaces that were stored at refrigeration temperature for up to 9 days caused a significant increase (1.8-3.6-fold as compared to the negative controls) in biofilm formation by luxS mutant (non AI-2 producing) generic E. coli and E. coli O157:H7 strains using a micro-titer plate-based biofilm assay. These results suggest that AI-2-like activity, which is present on the surfaces of tomatoes, has the potential to enhance the production of bacterial biofilms.

  4. Ice cloud formation potential by free tropospheric particles from long-range transport over the Northern Atlantic Ocean (United States)

    China, Swarup; Alpert, Peter A.; Zhang, Bo; Schum, Simeon; Dzepina, Katja; Wright, Kendra; Owen, R. Chris; Fialho, Paulo; Mazzoleni, Lynn R.; Mazzoleni, Claudio; Knopf, Daniel A.


    Long-range transported free tropospheric particles can play a significant role on heterogeneous ice nucleation. Using optical and electron microscopy we examine the physicochemical characteristics of ice nucleating particles (INPs). Particles were collected on substrates from the free troposphere at the remote Pico Mountain Observatory in the Azores Islands, after long-range transport and aging over the Atlantic Ocean. We investigate four specific events to study the ice formation potential by the collected particles with different ages and transport patterns. We use single-particle analysis, as well as bulk analysis to characterize particle populations. Both analyses show substantial differences in particle composition between samples from the four events; in addition, single-particle microscopy analysis indicates that most particles are coated by organic material. The identified INPs contained mixtures of dust, aged sea salt and soot, and organic material acquired either at the source or during transport. The temperature and relative humidity (RH) at which ice formed, varied only by 5% between samples, despite differences in particle composition, sources, and transport patterns. We hypothesize that this small variation in the onset RH may be due to the coating material on the particles. This study underscores and motivates the need to further investigate how long-range transported and atmospherically aged free tropospheric particles impact ice cloud formation.

  5. Photocatalytic oxidation of humic acid and its effect on haloacetic acid formation potential: a fluorescence spectrometry study. (United States)

    Xiaoju, Yan; Ruiling, Bao; Shuili, Yu; Qiongfang, Li; Wei, Chen


    By fluorescence spectrometry method, molecular conformation changes of humic acid (HA) during the photocatalytic oxidation process were studied. Haloacetic acids formation potential (HAAFP) changes during the oxidation process were also measured. The results indicated that aromatic rings of HA decreased and conjugated double bonds were destroyed at the beginning of the process. Meanwhile, organic matter with large molecular weight decomposed into intermediates with smaller molecular weight, such as tryptophan and tyrosine. HA can be degraded almost completely, but not be mineralized thoroughly. Structures of the intermediates were changing during the oxidation process. Molecular structure transformation of HA led to the fluctuation tendency of the HAAFP changes during the photocatalytic oxidation process. HAAFP increased to 1.22 times that in raw water after 30 min of ultraviolet (UV) radiation, and decreased to 0.66 times that in raw water after 60 min of photocatalytic oxidation.

  6. Hydrocarbon source potential of the Tanezzuft Formation, Murzuq Basin, south-west Libya: An organic geochemical approach (United States)

    El Diasty, W. Sh.; El Beialy, S. Y.; Anwari, T. A.; Batten, D. J.


    A detailed organic geochemical study of 20 core and cuttings samples collected from the Silurian Tanezzuft Formation, Murzuq Basin, in the south-western part of Libya has demonstrated the advantages of pyrolysis geochemical methods for evaluating the source-rock potential of this geological unit. Rock-Eval pyrolysis results indicate a wide variation in source richness and quality. The basal Hot Shale samples proved to contain abundant immature to early mature kerogen type II/III (oil-gas prone) that had been deposited in a marine environment under terrigenous influence, implying good to excellent source rocks. Strata above the Hot Shale yielded a mixture of terrigenous and marine type III/II kerogen (gas-oil prone) at the same maturity level as the Hot Shale, indicating the presence of only poor to fair source rocks.

  7. Evaluation of a High-Throughput Peptide Reactivity Format Assay for Assessment of the Skin Sensitization Potential of Chemicals (United States)

    Wong, Chin Lin; Lam, Ai-Leen; Smith, Maree T.; Ghassabian, Sussan


    The direct peptide reactivity assay (DPRA) is a validated method for in vitro assessment of the skin sensitization potential of chemicals. In the present work, we describe a peptide reactivity assay using 96-well plate format and systematically identified the optimal assay conditions for accurate and reproducible classification of chemicals with known sensitizing capacity. The aim of the research is to ensure that the analytical component of the peptide reactivity assay is robust, accurate, and reproducible in accordance with criteria that are used for the validation of bioanalytical methods. Analytical performance was evaluated using quality control samples (QCs; heptapeptides at low, medium, and high concentrations) and incubation of control chemicals (chemicals with known sensitization capacity, weak, moderate, strong, extreme, and non-sensitizers) with each of three synthetic heptapeptides, viz Cor1-C420 (Ac-NKKCDLF), cysteine- (Ac-RFAACAA), and lysine- (Ac-RFAAKAA) containing heptapeptides. The optimal incubation temperature for all three heptapeptides was 25°C. Apparent heptapeptide depletion was affected by vial material composition. Incubation of test chemicals with Cor1-C420, showed that peptide depletion was unchanged in polypropylene vials over 3-days storage in an autosampler but this was not the case for borosilicate glass vials. For cysteine-containing heptapeptide, the concentration was not stable by day 3 post-incubation in borosilicate glass vials. Although the lysine-containing heptapeptide concentration was unchanged in both polypropylene and borosilicate glass vials, the apparent extent of lysine-containing heptapeptide depletion by ethyl acrylate, differed between polypropylene (24.7%) and glass (47.3%) vials. Additionally, the peptide-chemical complexes for Cor1-C420-cinnamaldehyde and cysteine-containing heptapeptide-2, 4-dinitrochlorobenzene were partially reversible during 3-days of autosampler storage. These observations further highlight

  8. Variations in spectroscopic characteristics and disinfection byproduct formation potentials of dissolved organic matter for two contrasting storm events (United States)

    Nguyen, Hang Vo-Minh; Lee, Mi-Hee; Hur, Jin; Schlautman, Mark A.


    SummaryChanges in disinfection byproduct (DBP) precursors during storm events have not been intensively studied to date despite their dramatic impact on downstream drinking water supplies. For this study, variations in dissolved organic matter (DOM) spectroscopic properties and DBP formation potentials (DBPFPs), and the correlations among these various parameters, were investigated in river water samples collected under two contrasting storm event conditions (a strong summer storm versus a weak fall event). Fluorescence excitation-emission matrices (EEMs) combined with parallel factor analysis revealed that a combination of two humic-like components (C1 and C2) dominated the EEM data of the storm samples. Measured DOM characteristics and DBPFPs varied over a wider range during the more intense summer storm, exhibiting higher values of specific ultraviolet absorbance and C1/C2 ratio at high flow conditions. Variations in the fluorescence index were less pronounced during the two storm events. The spectroscopic changes were well explained by the input of terrestrial DOM sources from the surrounding catchments during the storms. Different trends of the formation potentials for trihalomethanes and haloacetic acids on the recession limb of the hydrographs suggest that the structures responsible for DBP precursors during storm events may not be the same for the two classes of DBPs. The ultraviolet light-absorbing moieties in DOM appear to play major roles in generating DBPs, as evidenced by their strong positive correlations with DBPFPs. Higher correlations with DBPFP for C1 versus C2 suggest that humic-like substances associated with more aromatic and condensed structures have a greater proclivity to generate DBP upon chlorination.

  9. Impact of Diagenesis on Biosignature Preservation Potential in Playa Lake Evaporites in Verde Formation, Arizona: Implications for Mars Exploration (United States)

    Shkolyar, S.; Farmer, J. D.


    Major priorities for Mars science include assessing the preservation potential and impact of diagenesis on biosignature preservation in aqueous sedimentary environments. We address these priorities with field and lab studies of playa evaporites of the Verde Formation (upper Pliocene) in Arizona. Evaporites studied include bottom-nucleated halite and displacive growth gypsum in magnesite-rich mudstone. These lithotypes are potential analogs for ancient lacustrine habitable environments on Mars. This study aimed to understand organic matter preservation potential under different diagenetic histories. Methods combined outcrop-scale field observations and lab analyses, including: (1) thin-section petrography to understand diagenetic processes and paragenesis; (2) X-ray powder diffraction to obtain bulk mineralogy; (3) Raman spectroscopy to identify and place phases (and kerogenous fossil remains) within a microtextural context; (4) Total Organic Carbon (TOC) analyses to estimate weight percentages of preserved organic carbon for each subfacies endmember; and (5) electron microprobe to create 2D kerogen maps semi-quantifying kerogen preservation in each subfacies. Results revealed complex diagenetic histories for each evaporite subfacies and pathways for organic matter preservation. Secondary gypsum grew displacively within primary playa lake mudstones during early diagenesis. Mudstones then experienced cementation by Mg-carbonates. Displacive-growth gypsum was sometimes dissolved, forming crystal molds. These molds were later either infilled by secondary sulfates or recrystallized to gypsum pseudomorphs with minor phases present (i.e., glauberite). These observations helped define taphonomic models for organic matter preservation in each subfacies. This work has the potential to inform in situ target identification, sampling strategies, and data interpretations for future Mars Sample Return missions (e.g., sample caching strategies for NASA's Mars 2020 mission).

  10. Potential Roles of Mhealth for Community Health Workers: Formative Research With End Users in Uganda and Mozambique. (United States)

    Thondoo, Meelan; Strachan, Daniel Ll; Nakirunda, Maureen; Ndima, Sozinho; Muiambo, Abel; Källander, Karin; Hill, Zelee


    Community health workers are reemerging as an essential component of health systems in low-income countries. However, there are concerns that unless they are adequately supported, their motivation and performance will be suboptimal. mHealth presents an opportunity to improve support for community health workers; however, most interventions to date have been designed through a top-down approach, rarely involve the end user, and have not focused on motivation. To use formative research to explore the views of community health workers in Uganda and Mozambique on the potential role of mHealth in their work delivering integrated community case management of children. We conducted 24 in-depth interviews and 5 focus group discussions with community health workers in Uganda and Mozambique. Data were collected on: current phone use, preferred phone and charger characteristics, and perceptions of a range of potential mHealth interventions. Interviews were conducted in the local language, were audio recorded and converted into expanded notes. Interviews were coded for key thematic areas using both deductive and inductive codes. Deductive codes included mHealth's potential impact on motivation and performance. The most salient roles of mHealth in improving performance and motivation were reducing the need for travel, improving efficiency and planning, receiving feedback and information, and improving communication with supervisors and other community health workers. This was mostly through improved voice and short message service (SMS) text communication. Specific components of mHealth interventions that participants felt could improve motivation included increasing their visibility and credibility through branding of phones; providing an SMS response to data submission; and sending SMS messages about the importance of their work and achievements, rather than just reminders or technical messages. Participants identified feasibility issues related to the language of SMS

  11. Rapid Determination of HAAs Formation Potential of the Reaction of Humic Acid with Chlorine or Chlorine Dioxide

    Institute of Scientific and Technical Information of China (English)

    ZHU Zhi-liang; GE Yuan-xin; ZHANG Rong-hua; MA Hong-mei; HAO Jian-fu


    On the basis of gas chromatography(GC) coupled with a short capillary column and an electron capture detector(ECD), a simple and rapid method for the determination of five haloacetic acids(HAAs) in drinking water was developed by the optimization of derivation conditions and the modification of gas chromatographic program. HAAs formation potential(HAAFP) of the reaction of humic acid with chlorine was determined via this method. The major advantages of the method are the simplicity of chromatographic temperature program and the short run time of GC. Dichloroacetic acid(DCAA) and Trichloroacetic acid(TCAA), which were detected in the determination of HAAFP, were rapidly formed in the first 72 h of the reaction of humic acid with chlorine. HAAFP of the reaction of humic acid with chlorine increased with the increase in the concentrations of humic acid and chlorine. The average HAAFP of the reaction of humic acid with chlorine was 39.9 μg/mg TOC under the experimental conditions. When the concentration of humic acid was 4 mg/L, the concentration of HAAs, which were produced in the reaction of humic acid with chorine, may exceed MCL of 60 μg/L HAAs as the water quality standards for urban water supply of China and the first stage of US EPA disinfection/disinfection by-products(D/DBP) rule; when the concentration of humic acid was 2 mg/L, the concentration of HAAs may exceed MCL of 30 μg/L HAAs for the second stage of US EPA D/DBP rule. When humic acid was reacted with chlorine dioxide, only DCAA was detected with a maximum concentration of 3.3 μg/L at a humic acid content of 6 mg/L. It was demonstrated that the substitution of chlorine dioxide for chorine may entirely or partly control the formation of HAAs and effectively reduce the health risk associated with disinfected drinking water.

  12. Evaluation of shale gas potential based on organic matter characteristics and gas concentration in the Devonian Horn River Formation, Canada (United States)

    Choi, Jiyoung; Hong, Sung Kyung; Lee, Hyun Suk


    In this study, we investigate organic matter characteristics from the analysis of Rock-Eval6 and biomarker, and estimate methane concentration from headspace method in the Devonian Horn River Formation, which is one of the largest shale reservoir in western Canada. The Horn River Formation consists of the Evie, Otterpark and Muskwa members in ascending stratigraphic order. Total Organic Carbon (TOC) ranges from 0.34 to 7.57 wt%, with an average of 2.78 wt%. The Evie, middle Otterpark and Muskwa members have an average TOC of more than 3%, whereas those of the lower and upper Otterpark Member are less than 2%. Based on Pristane/n-C17 (0.2 0.6) and Phytane/n-C18 (0.3 0.9) ratios, the organic matter in the Evie, middle Otterpark and Muskwa members mainly consists of type II kerogen which are formed in reducing marine environment. Thermal maturity were examined through the use of the distributions of Phenanthrene (P) and Methylphenantrenes (MP) based on m/z 178 and 192 mass chromatograms, respectively (Radke et al., 1982). The methylphenanthrene index (MPI-1) are calculated as follows : MPI-1 = 1.5 × (2MP+3MP)/(P+1MP+9MP), and Ro are calculated as follows : Ro = -0.6 × MPI-1 + 2.3. Estimated Ro ranges between 1.88 and 1.93%, which indicates the last stage of wet gas generation. The methane concentrations in headspace range from 15 to 914 ppmv, with an average of 73.5 ppmv. The methane concentrations in the Evie, middle Otterpark and Muskwa members (up to 914 ppmv) are higher than those of the lower and upper Otterpark Member (up to 75 ppmv). Considering the organic geochemical characteristics and gas concentrations, the shale gas potentials of the Evie, middle Otterpark and Muskwa members are higher than those of other members.

  13. Hydrocarbon potential evaluation of the source rocks from the Abu Gabra Formation in the Sufyan Sag, Muglad Basin, Sudan (United States)

    Qiao, Jinqi; Liu, Luofu; An, Fuli; Xiao, Fei; Wang, Ying; Wu, Kangjun; Zhao, Yuanyuan


    The Sufyan Sag is one of the low-exploration areas in the Muglad Basin (Sudan), and hydrocarbon potential evaluation of source rocks is the basis for its further exploration. The Abu Gabra Formation consisting of three members (AG3, AG2 and AG1 from bottom to top) was thought to be the main source rock formation, but detailed studies on its petroleum geology and geochemical characteristics are still insufficient. Through systematic analysis on distribution, organic matter abundance, organic matter type, organic matter maturity and characteristics of hydrocarbon generation and expulsion of the source rocks from the Abu Gabra Formation, the main source rock members were determined and the petroleum resource extent was estimated in the study area. The results show that dark mudstones are the thickest in the AG2 member while the thinnest in the AG1 member, and the thickness of the AG3 dark mudstone is not small either. The AG3 member have developed good-excellent source rock mainly with Type I kerogen. In the Southern Sub-sag, the AG3 source rock began to generate hydrocarbons in the middle period of Bentiu. In the early period of Darfur, it reached the hydrocarbon generation and expulsion peak. It is in late mature stage currently. The AG2 member developed good-excellent source rock mainly with Types II1 and I kerogen, and has lower organic matter abundance than the AG3 member. In the Southern Sub-sag, the AG2 source rock began to generate hydrocarbons in the late period of Bentiu. In the late period of Darfur, it reached the peak of hydrocarbon generation and its expulsion. It is in middle mature stage currently. The AG1 member developed fair-good source rock mainly with Types II and III kerogen. Throughout the geological evolution history, the AG1 source rock has no effective hydrocarbon generation or expulsion processes. Combined with basin modeling results, we have concluded that the AG3 and AG2 members are the main source rock layers and the Southern Sub-sag is

  14. Non-methane hydrocarbons (NMHCs) and their contribution to ozone formation potential in a petrochemical industrialized city, Northwest China (United States)

    Jia, Chenhui; Mao, Xiaoxuan; Huang, Tao; Liang, Xiaoxue; Wang, Yanan; Shen, Yanjie; Jiang, Wanyanhan; Wang, Huiqin; Bai, Zhilin; Ma, Minquan; Yu, Zhousuo; Ma, Jianmin; Gao, Hong


    Hourly air concentrations of fifty-three non-methane hydrocarbons (NMHCs) were measured at downtown and suburb of Lanzhou, a petrochemical industrialized city, Northwest China in 2013. The measured data were used to investigate the seasonal characteristics of NMHCs air pollution and their contributions to the ozone formation in Lanzhou. Annually averaged NMHCs concentration was 38.29 ppbv in downtown Lanzhou. Among 53 NMHCs, alkanes, alkenes, and aromatics accounted for 57%, 23% and 20% of the total NMHCs air concentration, respectively. The atmospheric levels of toluene and propane with mean values of 4.62 and 4.56 ppbv were higher than other NMHCs, respectively. The ambient levels of NMHCs in downtown Lanzhou were compared with measured NMHCs data collected at a suburban site of Lanzhou, located near a large-scale petrochemical industry. Results show that the levels of alkanes, alkenes, and aromatics in downtown Lanzhou were lower by factors of 3-11 than that in west suburb of the city. O3-isopleth plots show that ozone was formed in VOCs control area in downtown Lanzhou and NOx control area at the west suburban site during the summertime. Propylene-equivalent (Prop-Equiv) concentration and the maximum incremental reactivity (MIR) in downtown Lanzhou indicate that cis-2-butene, propylene, and m/p-xylene were the first three compounds contributing to ozone formation potentials whereas in the petrochemical industrialized west suburb, ethane, propene, and trans-2-Butene played more important role in the summertime ozone formation. Principal component analysis (PCA) and multiple linear regression (MLR) were further applied to identify the dominant emission sources and examine their fractions in total NMHCs. Results suggest that vehicle emission, solvent usage, and industrial activities were major sources of NMHCs in the city, accounting for 58.34%, 22.19%, and 19.47% of the total monitored NMHCs in downtown Lanzhou, respectively. In the west suburb of the city

  15. Geochemical Evidence for the Formation of Soils by Interaction Between Guano and Volcanic Rocks, Rata Island, Fernando de Noronha (Pernambuco

    Directory of Open Access Journals (Sweden)

    Sonia Maria Barros de Oliveira


    Full Text Available The phosphatic soils found in the northern part of the Rata island, in the Fernando de Noronha Archipelago, wereformed by reaction of bird guano with weathered mafi c rocks of the Quixaba Formation. Phosphate minerals identifi edinclude crandallite as a major constituent. The unique guano signature preserved in soil is characterized by high levelsof Cu, Pb, Zn, As, U, and Sr. On the other hand, the inheritance of the geochemical signature of the nepheline-basalts isdemonstrated by the anomalous concentrations of Ba, Nb, Ta, Cr, Hf, V and Zr in soils, and by the remarkable similaritybetween REE patterns in rock and soils.

  16. Evaluation of a high-throughput peptide reactivity format assay for assessment of the skin sensitization potential of chemicals

    Directory of Open Access Journals (Sweden)

    Chin Lin eWong


    Full Text Available The direct peptide reactivity assay (DPRA is a validated method for in vitro assessment of the skin sensitization potential of chemicals. In the present work, we describe a peptide reactivity assay using 96-well plate format and systematically identified the optimal assay conditions for accurate and reproducible classification of chemicals with known sensitizing capacity. The aim of the research is to ensure that the analytical component of the peptide reactivity assay is robust, accurate and reproducible in accordance with criteria that are used for the validation of bioanalytical methods. Analytical performance was evaluated using quality control samples (QCs; heptapeptides at low, medium and high concentrations and incubation of control chemicals (chemicals with known sensitization capacity, weak, moderate, strong, extreme and non-sensitizers with each of three synthetic heptapeptides, viz Cor1-C420 (Ac-NKKCDLF, cysteine- (Ac-RFAACAA and lysine- (Ac-RFAAKAA containing heptapeptides. The optimal incubation temperature for all three heptapeptides was 25°C. Apparent heptapeptide depletion was affected by vial material composition. Incubation of test chemicals with Cor1-C420, showed that peptide depletion was unchanged in polypropylene vials over 3-days storage in an autosampler but this was not the case for borosilicate glass vials. For cysteine-containing heptapeptide, the concentration was not stable by day 3 post-incubation in borosilicate glass vials. Although the lysine-containing heptapeptide concentration was unchanged in both polypropylene and borosilicate glass vials, the apparent extent of lysine-containing heptapeptide depletion by ethyl acrylate, differed between polypropylene (24.7% and glass (47.3% vials. Additionally, the peptide-chemical complexes for Cor1-C420-cinnamaldehyde and cysteine-containing heptapeptide-2,4-dinitrochlorobenzene were partially reversible during 3-days of autosampler storage. These observations further

  17. Time-resolved analysis of primary volatile emissions and secondary aerosol formation potential from a small-scale pellet boiler (United States)

    Czech, Hendryk; Pieber, Simone M.; Tiitta, Petri; Sippula, Olli; Kortelainen, Miika; Lamberg, Heikki; Grigonyte, Julija; Streibel, Thorsten; Prévôt, André S. H.; Jokiniemi, Jorma; Zimmermann, Ralf


    Small-scale pellet boilers and stoves became popular as a wood combustion appliance for domestic heating in Europe, North America and Asia due to economic and environmental aspects. Therefore, an increasing contribution of pellet boilers to air pollution is expected despite their general high combustion efficiency. As emissions of primary organic aerosol (POA) and permanent gases of pellet boilers are well investigated, the scope of this study was to investigate the volatile organic emissions and the formation potential of secondary aerosols for this type of appliance. Fresh and aged emissions were analysed by a soot-particle aerosol time-of-flight mass spectrometry (SP-AMS) and the molecular composition of the volatile precursors with single-photon ionisation time-of-flight mass spectrometry (SPI-TOFMS) at different pellet boiler operation conditions. Organic emissions in the gas phase were dominated by unsaturated hydrocarbons while wood-specific VOCs, e.g. phenolic species or substituted furans, were only detected during the starting phase. Furthermore, organic emissions in the gas phase were found to correlate with fuel grade and combustion technology in terms of secondary air supply. Secondary organic aerosols of optimised pellet boiler conditions (OPT, state-of-the-art combustion appliance) and reduced secondary air supply (RSA, used as a proxy for pellet boilers of older type) were studied by simulating atmospheric ageing in a Potential Aerosol Mass (PAM) flow reactor. Different increases in OA mass (55% for OPT, 102% for RSA), associated with higher average carbon oxidation state and O:C, could be observed in a PAM chamber experiment. Finally, it was found that derived SOA yields and emission factors were distinctly lower than reported for log wood stoves.

  18. The potential impact of 4-octylphenol on the basal and stimulated testosterone formation by isolated mice Leydig cells

    Directory of Open Access Journals (Sweden)

    Tomáš JAMBOR


    Full Text Available Octylphenol is biodegradation product of alkylphenolethoxylates frequently used in detergents, paints and other industrial applications. This compound is classified as an endocrine disruptor. Recent studies have hypothesized that occupational exposure to octylphenol poses adverse effects on reproductive system of humans and wildlife species. Enzymes involved in the steroid biosynthesis pathway are really sensitive targets for the action of various endocrine-disrupting chemicals. Aim of in vitro study was determined the effect of 4-octylphenol on basal and human chorionic gonadotropin stimulated testosterone formation of ICR mice Leydig cells. On the other hand, was classified potential impact of mentioned endocrine disruptor on Leydig cell viability after 44 h of cultivation. Cell suspension was cultured with addition of 0.04; 0.2; 1.0; 2.5 and 5.0 μg*mL-1 of 4-octylphenol and compared to the control. Hormone quantification from the medium was performed by enzyme-linked immunosorbent assay. Viability of cell suspension was determined by the metabolic activity assay. Unstimulated testosterone production significantly (P˂0.001 increased with 2.5 and 5.0 μg*mL-1 4-octylphenol. Cell viability was also significantly (P˂0.001; P˂0.05 stimulated by 4-octylphenol. Although human chorionic gonadotropin stimulated testosterone secretion was significantly (P˂0.05 affected by the lowest concentration (0.04 μg*mL-1 in the cell viability was recorded significantly (P˂0.001; P˂0.05 higher mitochondrial activity (1.0; 2.5 and 5.0 μg*mL-1. Considerably more detailed and systematic research in this area is required for a better understanding of potential risk to humans or animals.

  19. Volatile organic compounds speciation and their influence on ozone formation potential in an industrialized urban area in Brazil. (United States)

    Galvão, Elson Silva; Santos, Jane Meri; Reis Junior, Neyval Costa; Stuetz, Richard Michael


    Speciation and the influence on the ozone formation potential (OFP) from volatile organic compounds (VOCs) have been studied between February June 2013 in Vitória, ES, Brazil. Passive samplers were installed at three air-quality monitoring stations and a total of 96 samplings were collected. A total of 78 VOCs were characterized by gas chromatograph-mass spectrometer. The predominant group was organic acids, followed by alcohols and substituted aromatics and 14 precursor species were quantified. An analysis correlating concentrations with wind direction was conducted to identify possible sources. The OFP was calculated applying the scale of maximum incremental reactivity proposed by Carter.[ 23 ] Ozone precursors with the greatest OFP such as undecane, toluene, ethylbenzene and m, p-xylene compounds were the most abundant with means of 0.855, 0.365, 0.259 and 0.289 µg m(-3), respectively. The benzene, toluene, ethylbenzene and xylene (BTEX) group was found below the limits considered harmful to the health of the population living in Vitória. The OFP calculated for the precursors group was 22.55 µg m(-3) for the rainy season and 32.11 µg m(-3) for the dry season. The VOC/NOx ratio in Vitória is approximately 1.71, indicating that the region has a VOC-limiting condition for the production of ozone.

  20. Formation potentials of typical disinfection byproducts and changes of genotoxicity for chlorinated tertiary effluent pretreated by ozone. (United States)

    Cao, Nan; Miao, Tingting; Li, Kuixiao; Zhang, Yu; Yang, Min


    The effects of ozonation on the formation potential of typical disinfection byproducts (DBPs) and the changes of genotoxicity during post chlorination of tertiary effluent from a sewage treatment plant were investigated. Ozonation enhanced the yields of all detected chlorine DBPs except CHCl3. At a chlorine dose of 5 mg/L, the three brominated THMs and five HAAs increased, while chloroform decreased with the increase of ozone dose from 0 to 10 mg/L (ozone dose in consumption base). At a chlorine dose of 10 mg/L, the two mixed bromochloro species THMs and two dominant HAAs (DCAA and TCAA) increased firstly and then decreased with the increase of ozone dose, with the turning point approximately occurring at an ozone dose of 5 mg/L. The genotoxicity detected using umu test, on the other hand, was removed from 7 microg 4-NQO/L to a negligible level by ozonation under an ozone dose of 5 mg/L. Chlorination could further remove the genotoxicity to some extent. It was found that SUVA (UV absorbance divided by DOC concentration) might be used as an indicative parameter for monitoring the removal of genotoxicity during the oxidation.

  1. Establishment and Characterization of Human Germline Stem Cell Line with Unlimited Proliferation Potentials and no Tumor Formation. (United States)

    Hou, Jingmei; Niu, Minghui; Liu, Linhong; Zhu, Zijue; Wang, Xiaobo; Sun, Min; Yuan, Qingqing; Yang, Shi; Zeng, Wenxian; Liu, Yang; Li, Zheng; He, Zuping


    Spermatogonial stem cells (SSCs) have significant applications in both reproductive and regenerative medicine. However, primary human SSCs are very rare, and a human SSC line has not yet been available. In this study, we have for the first time reported a stable human SSC line by stably expressing human SV40 large T antigen. RT-PCR, immunocytochemistry, and Western blots revealed that this cell line was positive for a number of human spermatogonial and SSC hallmarks, including VASA, DAZL, MAGEA4, GFRA1, RET, UCHL1, GPR125, PLZF and THY1, suggesting that these cells are human SSCs phenotypically. Proliferation analysis showed that the cell line could be expanded with significant increases of cells for 1.5 years, and high levels of PCNA, UCHL1 and SV40 were maintained for long-term culture. Transplantation assay indicated that human SSC line was able to colonize and proliferate in vivo in the recipient mice. Neither Y chromosome microdeletions of numerous genes nor tumor formation was observed in human SSC line although there was abnormal karyotype in this cell line. Collectively, we have established a human SSC line with unlimited proliferation potentials and no tumorgenesis, which could provide an abundant source of human SSCs for their mechanistic studies and translational medicine.

  2. Temperature-Responsive Gelation of Type I Collagen Solutions Involving Fibril Formation and Genipin Crosslinking as a Potential Injectable Hydrogel

    Directory of Open Access Journals (Sweden)

    Shunji Yunoki


    Full Text Available We investigated the temperature-responsive gelation of collagen/genipin solutions using pepsin-solubilized collagen (PSC and acid-solubilized collagen (ASC as substrates. Gelation occurred in the PSC/genipin solutions at genipin concentrations 0–2 mM under moderate change in temperature from 25 to 37°C. The PSC/genipin solutions exhibited fluidity at room temperature for at least 30 min, whereas the ASC/genipin solutions rapidly reached gel points. In specific cases PSC would be preferred over ASC as an injectable gel system. The temperature-responsive gelation of PSC/genipin solutions was due to temperature responses to genipin crosslinking and collagen fibril formation. The elastic modulus of the 0.5% PSC/genipin gel system could be adjusted in a range of 2.5 to 50 kPa by the PSC and genipin concentrations, suggesting that a PSC/genipin solution is a potential injectable gel system for drug and cell carriers, with mechanical properties matching those of living tissues.

  3. Volume term of work of critical nucleus formation in terms of chemical potential difference relative to equilibrium one

    CERN Document Server

    Mori, Atsushi


    The work of formation of a critical nucleus is sometimes written as W=n{\\Delta}{\\mu}+{\\gamma}A. The first term W_{vol}=n{\\Delta}{\\mu} is called the volume term and the second term {\\gamma}A the surface term with {\\gamma} being the interfacial tension and A the area of the nucleus. Nishioka and Kusaka [J. Chem. Phys. 96 (1992) 5370] derived W_{vol}=n{\\Delta}{\\mu} with n=V_{\\beta}/v_{\\beta} and {\\Delta}{\\mu}={\\mu}_{\\beta}(T,p_{\\alpha})-{\\mu}_{\\alpha}(T,p_{\\alpha}) by rewriting W_{vol}=-(p_{\\beta}-p_{\\alpha})V_{\\beta} by integrating the isothermal Gibbs-Duhem relation for an incompressible {\\beta} phase, where {\\alpha} and {\\beta} represent the parent and nucleating phases, V_{\\beta} is the volume of the nucleus, v_{\\beta}, which is constant, the molecular volume of the {\\beta} phase, {\\mu}, T, and p denote the chemical potential, the temperature, and the pressure, respectively. We note here that {\\Delta}{\\mu}={\\mu}_{\\beta}(T,p_{\\alpha})-{\\mu}_{\\alpha}(T,p_{\\alpha}) is, in general, not a directly measurable quan...

  4. Hypusine: its post-translational formation in eukaryotic initiation factor 5A and its potential role in cellular regulation. (United States)

    Park, M H; Wolff, E C; Folk, J E


    The amino acid, hypusine [N epsilon-(4-amino-2-hydroxybutyl) lysine], a unique component of one cellular protein, eukaryotic translation initiation factor 5A (eIF-5A, old terminology eIF-4D), is formed post-translationally in two enzymatic steps: (i) transfer of the 4-aminobutyl moiety of the polyamine spermidine to the epsilon-amino group of a single specific lysine residue in the eIF-5A precursor protein to form an intermediate, deoxyhypusine, and (ii) subsequent hydroxylation in this 4-aminobutyl portion. Hypusine is produced soon after the translation of eIF-5A mRNA; the modification is essentially irreversible. Hypusine is found in all eukaryotes examined as well as in archaebacteria; it does not occur in eubacteria. The protein containing hypusine from each species displays a high degree of amino acid identity; the sequence of amino acids surrounding the hypusine residue is strictly conserved, suggesting the importance of the hypusine modification throughout evolution. Expression of one of the two yeast eIF-5A genes is required for survival and the lysine codon at the site of hypusine synthesis is vital for yeast growth. The precise cellular function of eIF-5A remains to be elucidated; however, eIF-5A stimulates methionyl-puromycin synthesis in a model assay for translation initiation and eIF-5A precursors containing lysine in place of hypusine are inactive in this assay. This provides evidence that the hypusine modification is needed for eIF-5A activity. In view of the important role of hypusine in eIF-5A and because of the narrow specificities of the enzymes involved in formation of this unusual amino acid, the hypusine biosynthetic steps offer promising targets for intervention in cellular proliferation. Spermidine analogs that are inhibitors of deoxyhypusine synthase in vitro also cause inhibition of hypusine formation in cells, together with a reduction in protein synthesis and in cell growth. In addition, certain metal chelating inhibitors of

  5. The role of the ion-molecule and molecule-molecule interactions in the formation of the two-ion average force interaction potential

    CERN Document Server

    Ajrian, E A; Sidorenko, S N


    The effect of the ion-molecule and intermolecular interactions on the formation of inter-ion average force potentials is investigated within the framework of a classical ion-dipole model of electrolyte solutions. These potentials are shown to possess the Coulomb asymptotics at large distances while in the region of mean distances they reveal creation and disintegration of solvent-shared ion pairs. The calculation results provide a qualitatively authentic physical picture which is experimentally observed in strong electrolytes solutions. In particular, an increased interaction between an ion and a molecule enhances formation of ion pairs in which the ions are separated by one solvent molecule

  6. Evaluation of potential reaction mechanisms leading to the formation of coniferyl alcohol α-linkages in lignin: a density functional theory study. (United States)

    Watts, Heath D; Mohamed, Mohamed Naseer Ali; Kubicki, James D


    Five potential reaction mechanisms, each leading to the formation of an α-O-4-linked coniferyl alcohol dimer, and one scheme leading to the formation of a recently proposed free-radical coniferyl alcohol trimer were assessed using density functional theory (DFT) calculations. These potential reaction mechanisms were evaluated using both the calculated Gibbs free energies, to predict the spontaneity of the constituent reactions, and the electron-density mapped Fukui function, to determine the most reactive sites of each intermediate species. The results indicate that each reaction in one of the six mechanisms is thermodynamically favorable to those in the other mechanisms; what is more, the Fukui function for each free radical intermediate corroborates with the thermochemical results for this mechanism. This mechanism proceeds via the formation of two distinct free-radical intermediates, which then react to produce the four α-O-4 stereoisomers.


    NARCIS (Netherlands)



    The Gibbs free energies of formation of various classes of halogenated aromatic compounds were estimated with Benson's method. The data were used to evaluate the potential of these compounds to serve as electron acceptors in anaerobic environments. The results indicate that for (chloro) benzenes, be

  8. Plant extracts, spices, and essential oils inactivate E. coli O157:H7 pathogens and reduce formation of potentially carcinogenic heterocyclic amines in grilled beef patties (United States)

    Meats need to be sufficiently heated to inactivate foodborne pathogens such as Escherichia coli O157:H7. High-temperature heat treatment used to prepare well-done meats could, however, increase the formation of potentially carcinogenic heterocyclic amines (HCAs). The objective of this study was to ...


    NARCIS (Netherlands)



    The Gibbs free energies of formation of various classes of halogenated aromatic compounds were estimated with Benson's method. The data were used to evaluate the potential of these compounds to serve as electron acceptors in anaerobic environments. The results indicate that for (chloro) benzenes,

  10. Potential for Carbon Dioxide Sequestration and Enhanced Oil Recovery in the Vedder Formation, Greeley Field, San Joaquin Valley, California. (United States)

    Jameson, S.


    Most scientists agree that greenhouse gases (GHG) such as carbon dioxide (CO2), Methane (CH4), and nitrous oxide (N2O) are major contributors to the global warming trend and climate change. One effort to mitigate anthropogenic sourced CO2 is through carbon capture and sequestration. Depleted oil and gas reservoirs due to their known trapping capability, in-place infrastructure, and proximity to carbon emission sources are good candidates for possible CO2 storage. The Vedder formation is one of three reservoirs identified in the San Joaquin Basin that meets standards for possible storage. An analysis of net fluid production data (produced minus injected) from discovery to the present is used to determine the reservoir volume available for CO2 storage. Data regarding reservoir pressure response to injection and production of fluids include final shut-in pressures from drill stem test, static bottom-hole pressure measurements from well completion histories, and idle well fluid level measurements for recent pressure data. Proprietary experimental pressure, volume and temperature data (PVT), gas oil ratios (GOR), well by well permeability, porosity, and oil gravity, and relative permeability and perforation intervals are used to create static and dynamic multiphase fluid flow models. All data collected was logged and entered into excel spreadsheets and mapping software to create subsurface structure, reservoir thickness and pressure maps, cross sections, production/injection charts on a well-by-well basis, and both static and dynamic flow models. This data is used to determine storage capacity and the amount of pressure variance within the field to determine how the reservoir will react to CO2 injection and to gain insight into the subsurface fluid movement of CO2. Results indicate a homogenous field with a storage capacity of approximately 26 Million Metric Tons of CO2. Analysis of production by stream and pressure change through time indicates a strong water drive

  11. Potential energies of characteristic atoms on basis of experimental heats of formation of AuCu and AuCu_3 compounds (Ⅰ)

    Institute of Scientific and Technical Information of China (English)

    XIE You-qing; LIU Xin-bi; LI Xiao-bo; PENG Hong-jian; NIE Yao-zhuang


    The systematic science of alloys(SSA) is a framework of the total energy and total volume able to be separated. The potential energy sequences of characteristic atoms at the central sites of the basic clusters in the fcc-based lattice Au-Cu system are separated out from smaller experimental heats of formation of L10-AuCu and L1_2-AuCu_3 compounds only, by nine potential energy E-functions and through the use of structural unit inversion method. From these potential energy sequences, the potential energies and heats of formation of the disordered Au1-xCux alloys at 0 K are calculated. The potential energies, heats of formation and Tc-temperatures of order-disorder transitions of the L1_0-AuCu, L1_2-Au_3Cu and L1_2-AuCu_3 compounds, as well as the Au_3Cu-, AuCu- and AuCu_3~- type ordered alloys with maximal ordering degrees are calculated too. The results show that the 5th E-function may be chosen for developing it into the free energy-, enthalpy-, vibrational energy- and vibrational entropy-functions for describing thermodynamic properties of the compounds, ordered and disordered phases and for establishing the phase diagram of the Au-Cu system in the future.

  12. Palynology, palynofacies and petroleum potential of the Upper Cretaceous-Eocene Matulla, Brown Limestone and Thebes formations, Belayim oilfields, central Gulf of Suez, Egypt (United States)

    El Diasty, W. Sh.; El Beialy, S. Y.; Abo Ghonaim, A. A.; Mostafa, A. R.; El Atfy, H.


    Palynological, palynofacies and organic geochemical results of 46 samples retrieved from the Upper Cretaceous - Eocene Matulla, Brown Limestone and Thebes formations, Belayim oilfields, central Gulf of Suez, Egypt are presented. The two latter formations are not dated palynologically as their lithology is not promising for palynological yield. However the Matulla Formation is dated as Turonian-Santonian age, based on the combined evidence of pollen and dinocysts. Palynofacies analysis carried out under both transmitted and fluorescent microscopy indicated that both the Thebes and Brown Limestone formations are deposited under a distal suboxic-anoxic environment. On the other hand, the Turonian-Santonian Matulla Formation supported the existence of a marginal marine deposition under dysoxic-anoxic basin to proximal suboxic-anoxic shelf environments. Rock-Eval pyrolysis and TOC results indicated that most of the studied formations are thermally immature to marginally mature and have a good petroleum potential. They are organically-rich in both oil- and gas-prone kerogen Type-II and II/III, deposited under marine reducing conditions favorable for hydrocarbon generation and expulsion.

  13. Metallic Glass Formation by Ion Mixing and Calculation of Glass-Forming-Ability from Inter-Atomic Potential in the Binary Metal Systems

    Institute of Scientific and Technical Information of China (English)

    LI Zhengcao; LAI Wensheng; LIU Baixin


    In this article,a brief summary of the up-to-date progress of metallic glass formation by ion mixing of metallic multilayers in the binary metal systems is first presented.Secondly,thermodynamic modeling of metallic glass formation is developed with special consideration of the interfacial free energy of the multilayers.Thirdly,results of molecular dynamics simulations for some representative systems are presented to show the calculation of the glass-forming ability directly from the inter-atomic potential of the binary metal systems.

  14. Sedimentology, petrology, and gas potential of the Brallier Formation: upper Devonian turbidite facies of the Central and Southern Appalachians

    Energy Technology Data Exchange (ETDEWEB)

    Lundegard, P.D.; Samuels, N.D.; Pryor, W.A.


    The Upper Devonian Brallier Formation of the central and southern Appalachian basin is a regressive sequence of siltstone turbidites interbedded with mudstones, claystones, and shales. It reaches 1000 meters in thickness and overlies basinal mudrocks and underlies deltaic sandstones and mudrocks. Facies and paleocurrent analyses indicate differences between the depositional system of the Brallier Formation and those of modern submarine fans and ancient Alpine flysch-type sequences. The Brallier system is of finer grain size and lower flow intensity. In addition, the stratigraphic transition from turbidites to deltaic sediments is gradual and differs in its facies succession from the deposits of the proximal parts of modern submarine fans. Such features as massive and pebbly sandstones, conglomerates, debris flows, and massive slump structures are absent from this transition. Paleocurrents are uniformly to the west at right angles to basin isopach, which is atypical of ancient turbidite systems. This suggests that turbidity currents had multiple point sources. The petrography and paleocurrents of the Brallier Formation indicate an eastern source of sedimentary and low-grade metasedimentary rocks with modern relief and rainfall. The depositional system of the Brallier Formation is interpreted as a series of small ephemeral turbidite lobes of low flow intensity which coalesced in time to produce a laterally extensive wedge. The lobes were fed by deltas rather than submarine canyons or upper fan channel systems. This study shows that the present-day turbidite facies model, based mainly on modern submarine fans and ancient Alpine flysch-type sequences, does not adequately describe prodeltaic turbidite systems such as the Brallier Formation. Thickly bedded siltstone bundles are common features of the Brallier Formation and are probably its best gas reservoir facies, especially when fracture porosity is well developed.

  15. Ethanolic extract of Actaea racemosa (black cohosh) potentiates bone nodule formation in MC3T3-E1 preosteoblast cells. (United States)

    Chan, B Y; Lau, K S; Jiang, B; Kennelly, E J; Kronenberg, F; Kung, A W C


    Aceaea racemosa (formerly Cimicifuga racemosa, black cohosh, AR) extracts have been widely used as an alternative to hormonal replacement therapy for menopausal symptoms. Recent evidences suggest AR extracts are also effective in protecting against postmenopausal bone loss. To determine whether AR has any direct anabolic effect on osteoblasts, we investigated the ethanolic extract of AR on bone nodule formation in mouse MC3T3-E1 preosteoblast cells. AR did not stimulate osteoblast proliferation. Rather, at high doses of 1000 ng/mL for 48 h, AR suppressed (7.2+/-0.9% vs. control) osteoblast proliferation. At 500 ng/mL, a significant increase in bone nodule formation was seen with Von Kossa staining. Using quantitative PCR analysis, AR was shown to enhance the gene expression of runx2 and osteocalcin. Co-treatment with ICI 182,780, the selective estrogen receptor antagonist, abolished the stimulatory effect of AR on runx2 and osteocalcin gene induction, as well as on bone nodule formation in MC3T3-E1 cells. This is a first report of the direct effect of AR on enhancement of bone nodule formation in osteoblasts, and this action was mediated via an estrogen receptor-dependent mechanism. The results provide a scientific rationale at the molecular level for the claim that AR can offer effective prevention of postmenopausal bone loss.

  16. CO2 hydrate formation and dissociation in cooled porous media: a potential technology for CO2 capture and storage. (United States)

    Yang, Mingjun; Song, Yongchen; Jiang, Lanlan; Zhu, Ningjun; Liu, Yu; Zhao, Yuechao; Dou, Binlin; Li, Qingping


    The purpose of this study was to investigate the hydrate formation and dissociation with CO2 flowing through cooled porous media at different flow rates, pressures, temperatures, and flow directions. CO2 hydrate saturation was quantified using the mean intensity of water. The experimental results showed that the hydrate block appeared frequently, and it could be avoided by stopping CO2 flooding early. Hydrate formed rapidly as the temperature was set to 274.15 or 275.15 K, but the hydrate formation delayed when it was 276.15 K. The flow rate was an important parameter for hydrate formation; a too high or too low rate was not suitable for CO2 hydration formation. A low operating pressure was also unacceptable. The gravity made hydrate form easily in the vertically upward flow direction. The pore water of the second cycle converted to hydrate more completely than that of the first cycle, which was a proof of the hydrate "memory effect". When the pressure was equal to atmospheric pressure, hydrate did not dissociate rapidly and abundantly, and a long time or reduplicate depressurization should be used in industrial application.

  17. The potential role of kinesin and dynein in Golgi scattering and cytoplasmic vacuole formation during acute experimental pancreatitis

    Institute of Scientific and Technical Information of China (English)

    Ina A Weber; Igor Buchwalow; Daniela Hahn; Wolfram Domschke; Markus M Lerch; Jürgen Schnekenburger


    @@ Dear Editor, Acute pancreatitis is initiated in pancreatic acinar cells and characterized by a profound disturbance in intracel-lular vesicle transport. Moreover, secretion of pancreatic zymogens is blocked, paralleled by the formation of cytoplasmic vacuoles with premature protease activation that precedes cellular necrosis and organ damage.

  18. The potential to intensify sulforaphane formation in cooked broccoli (Brassica oleracea var. italica) using mustard seeds (Sinapis alba). (United States)

    Ghawi, Sameer Khalil; Methven, Lisa; Niranjan, Keshavan


    Sulforaphane, a naturally occurring cancer chemopreventive, is the hydrolysis product of glucoraphanin, the main glucosinolate in broccoli. The hydrolysis requires myrosinase isoenzyme to be present in sufficient activity; however, processing leads to its denaturation and hence reduced hydrolysis. In this study, the effect of adding mustard seeds, which contain a more resilient isoform of myrosinase, to processed broccoli was investigated with a view to intensify the formation of sulforaphane. Thermal inactivation of myrosinase from both broccoli and mustard seeds was studied. Thermal degradation of broccoli glucoraphanin was investigated in addition to the effects of thermal processing on the formation of sulforaphane and sulforaphane nitrile. Limited thermal degradation of glucoraphanin (less than 12%) was observed when broccoli was placed in vacuum sealed bag (sous vide) and cooked in a water bath at 100°C for 8 and 12 min. Boiling broccoli in water prevented the formation of any significant levels of sulforaphane due to inactivated myrosinase. However, addition of powdered mustard seeds to the heat processed broccoli significantly increased the formation of sulforaphane.

  19. An Analysis of the Potential for Enhanced Oil Recovery in the Shannon Formation at Naval Petroleum Reserve Number 3. (United States)


    logs and U. S. Geologic Survey maps, the Shannon formation contained approximately 180 MMtbl of oil, and that primary production would be limited to... Spcf oto i opesr e ntAe:$2000...PerforI Log .9in $830.00 S40150.00 I M P. .. .. . ..... .... ............. . ..................... :......... I

  20. The Eocene Rusayl Formation, Oman, carbonaceous rocks in calcareous shelf sediments: Environment of deposition, alteration and hydrocarbon potential

    Energy Technology Data Exchange (ETDEWEB)

    Dill, H.G.; Wehner, H.; Kus, J. [Federal Institute for Geosciences and Natural Resources, P.O. Box 510163, D-30631 Hannover (Germany); Botz, R. [University Kiel, Geological-Paleontological Department, Olshausenstrasse 40-60, D-24118 Kiel (Germany); Berner, Z.; Stueben, D. [Technical University Karlsruhe, Institute for Mineralogy and Geochemistry, Fritz-Haber-Weg 2, D-76131 Karlsruhe (Germany); Al-Sayigh, A. [Sultan Qaboos University, Geological Dept. PO Box 36, Al-Khod (Oman)


    Paralic carbonaceous series intercalated among calcareous shelf sediments have seldom been investigated. During the early Eocene, calcareous and siliciclastic sediments were deposited on a wide shelf in front of low-reliefed hinterland in the Al Khawd region in NE Oman. The siliciclastic-calcareous sediments originated from strongly reworked debris of the Arabic Shield. The underlying Semail Ophiolite did not act as a direct source of debris but provided some heat to increase the maturity of carbonaceous rocks and modify the isotope signal of the calcareous minerals in the Rusayl Formation. A multidisciplinary approach involving sedimentology, mineralogy, chemistry, coal petrography and paleontology resulted in the establishment of nine stratigraphic lithofacies units and provides the reader with a full picture from deposition of the mixed carbonaceous-calcareous-siliciclastic rocks to the most recent stages of post-depositional alteration of the Paleogene formations. The calcareous Jafnayn Formation (lithofacies unit I) developed in a subtidal to intertidal regime, influenced episodically by storms. Deepening of the calcareous shelf towards younger series was ground to a halt by paleosols developing on a disconformity (lithofacies unit II) and heralding the onset of the Rusayl Formation. The stratigraphic lithofacies units III and IV reflect mangrove swamps which from time to time were flooded through washover fans from the open sea. The presence of Spinozonocolpites and the taxon Avicennia, which today belong to a coastal marsh vegetational community, furnish palynological evidence to the idea of extensive mangrove swamps in the Rusayl Formation [El Beialy, S.Y., 1998. Stratigraphic and palaeonenvironmental significance of Eocene palynomorphs from the Rusayl Shale Formation, Al Khawd, northern Oman. Review of Palaeobotany and Palynology 102, 249-258]. During the upper Rusayl Formation (lithofacies units V through VII) algal mats episodically flooded by marine

  1. Theoretical and methodological basis for the formation and evaluation of the level of the economic system's strategic economic potential

    Directory of Open Access Journals (Sweden)

    Kljushin Vladislav Vladimirovich


    Full Text Available The current level of business activity of socio-economic systems of different scale and insufficient to increase their overall potential. To solve this problem, the first priority is the effective management of their strategic and economic potential. Managerial decision-making about the use of economic resources strategic socio-economic systems requires the development of a methodology to identify and evaluate strategic and economic potential.

  2. Alteration of Basaltic Glass to Mg/Fe-Smectite under Acidic Conditions: A Potential Smectite Formation Mechanism on Mars (United States)

    Peretyazhko, Tanya; Sutter, Brad; Ming, Douglas W.


    Phyllosilicates of the smectite group including Mg- and Fe-saponite and Fe(III)-rich nontronite have been identified on Mars. Smectites are believed to be formed under neutral to alkaline conditions that prevailed on early Mars. This hypothesis is supported by the observation of smectite and carbonate deposits in Noachian terrain on Mars. However, smectite may have formed under mildly acidic conditions. Abundant smectite formations have been detected as layered deposits hundreds of meters thick in intracrater depositional fans and plains sediments, while no large deposits of carbonates are found. Development of mildly acidic conditions at early Mars might allow formation of smectite but inhibit widespread carbonate precipitation. Little is known regarding the mechanisms of smectite formation from basaltic glass under acidic conditions. The objective of this study was to test a hypothesis that Mars-analogue basaltic glass alters to smectite minerals under acidic conditions (pH 4). The effects of Mg and Fe concentrations and temperature on smectite formation from basaltic glass were evaluated. Phyllosilicate synthesis was performed in batch reactors (Parr acid digestion vessel) under reducing hydrothermal conditions at 200 C and 100 C. Synthetic basaltic glass with a composition similar to that of the Gusev crater rock Adirondack (Ground surface APXS measurement) was used in these experiments. Basaltic glass was prepared by melting and quenching procedures. X-ray diffraction (XRD) analysis indicated that the synthesized glass was composed of olivine, magnetite and X-ray amorphous phase. Samples were prepared by mixing 250 mg Adirondack with 0.1 M acetic acid (final pH 4). In order to study influence of Mg concentration on smectite formation, experiments were performed with addition of 0, 1 and 10 mM MgCl2. After 1, 7 and 14 day incubations the solution composition was analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and the altered glass and formed

  3. PPCP degradation by UV/chlorine treatment and its impact on DBP formation potential in real waters. (United States)

    Yang, Xin; Sun, Jianliang; Fu, Wenjie; Shang, Chii; Li, Yin; Chen, Yiwei; Gan, Wenhui; Fang, Jingyun


    The ultraviolet/chlorine (UV/chlorine) water purification process was evaluated for its ability to degrade the residues of pharmaceuticals and personal care products (PPCPs) commonly found in drinking water sources. The disinfection byproducts (DBPs) formed after post-chlorination were documented. The performance of the UV/chlorine process was compared with that of the UV/hydrogen peroxide (UV/H2O2) process in treating three types of sand-filtered natural water. Except caffeine and carbamazepine residues, the UV/chlorine process was found to be 59-99% effective for feed water with a high level of dissolved organic carbon and alkalinity, and 27-92% effective for water with a high ammonia content. Both chlorine radicals and hydroxyl radicals were found to contribute to the observed PPCP degradation. The removal efficiencies of chlorine- and UV-resistant PPCPs such as carbamazepine and caffeine were 2-3 times greater than in the UV/H2O2 process in waters not enriched with ammonia. UV/chlorine treatment slightly enhanced the formation chloral hydrate (CH), haloketone (HK) and trichloronitromethane (TCNM). It reduced haloacetonitrile (HAN) formation during the post-chlorination in comparison with the UV/H2O2 process. In waters with high concentrations of ammonia, the UV/chlorine process was only 5-7% more effective than the UV/H2O2 process, and it formed slightly more THMs, HKs and TCNM along with reduced formation of CH and HAN. The UV/chlorine process is thus recommended as a good alternative to UV/H2O2 treatment for its superior PPCP removal without significantly enhancing DBP formation.

  4. Influence of Interleukin-1 Beta on Platelet-Poor Plasma Clot Formation: A Potential Impact on Early Bone Healing.

    Directory of Open Access Journals (Sweden)

    Xin Wang

    Full Text Available Hematoma quality (especially the fibrin matrix plays an important role in the bone healing process. Here, we investigated the effect of interleukin-1 beta (IL-1β on fibrin clot formation from platelet-poor plasma (PPP.Five-milliliter of rat whole-blood samples were collected from the hepatic portal vein. All blood samples were firstly standardized via a thrombelastograph (TEG, blood cell count, and the measurement of fibrinogen concentration. PPP was prepared by collecting the top two-fifths of the plasma after centrifugation under 400 × g for 10 min at 20°C. The effects of IL-1β cytokines on artificial fibrin clot formation from PPP solutions were determined by scanning electronic microscopy (SEM, confocal microscopy (CM, turbidity, and clot lysis assays.The lag time for protofibril formation was markedly shortened in the IL-1β treatment groups (243.8 ± 76.85 in the 50 pg/mL of IL-1β and 97.5 ± 19.36 in the 500 pg/mL of IL-1β compared to the control group without IL-1β (543.8 ± 205.8. Maximal turbidity was observed in the control group. IL-1β (500 pg/mL treatment significantly decreased fiber diameters resulting in smaller pore sizes and increased density of the fibrin clot structure formed from PPP (P < 0.05. The clot lysis assay revealed that 500 pg/mL IL-1β induced a lower susceptibility to dissolution due to the formation of thinner and denser fibers.IL-1β can significantly influence PPP fibrin clot structure, which may affect the early bone healing process.

  5. Expanding the potential for saline formations : modeling carbon dioxide storage, water extraction and treatment for power plant cooling.

    Energy Technology Data Exchange (ETDEWEB)


    The National Water, Energy and Carbon Sequestration simulation model (WECSsim) is being developed to address the question, 'Where in the current and future U.S. fossil fuel based electricity generation fleet are there opportunities to couple CO{sub 2} storage and extracted water use, and what are the economic and water demand-related impacts of these systems compared to traditional power systems?' The WECSsim collaborative team initially applied this framework to a test case region in the San Juan Basin, New Mexico. Recently, the model has been expanded to incorporate the lower 48 states of the U.S. Significant effort has been spent characterizing locations throughout the U.S. where CO{sub 2} might be stored in saline formations including substantial data collection and analysis efforts to supplement the incomplete brine data offered in the NatCarb database. WECSsim calculates costs associated with CO{sub 2} capture and storage (CCS) for the power plant to saline formation combinations including parasitic energy costs of CO{sub 2} capture, CO{sub 2} pipelines, water treatment options, and the net benefit of water treatment for power plant cooling. Currently, the model can identify the least-cost deep saline formation CO{sub 2} storage option for any current or proposed coal or natural gas-fired power plant in the lower 48 states. Initial results suggest that additional, cumulative water withdrawals resulting from national scale CCS may range from 676 million gallons per day (MGD) to 30,155 MGD depending on the makeup power and cooling technologies being utilized. These demands represent 0.20% to 8.7% of the U.S. total fresh water withdrawals in the year 2000, respectively. These regional and ultimately nation-wide, bottom-up scenarios coupling power plants and saline formations throughout the U.S. can be used to support state or national energy development plans and strategies.

  6. Investigation of in-situ electrode formation with respect to potential applications in intermediate temperature solid oxide fuel cells


    Fang, Qingping


    The novel SEA (Single Element Arrangement) concept for SOFC consists of a single material to complete the whole galvanic cell. Essential of the SEA concept is the in-situ electrode formation. Such kind of material becomes mixed ionic and electronic conducting in the surface region, while still being predominantly ionically conducting inside under the working conditions. Electronic short circuit will be blocked by the region where ionic conduction is dominant, allowing the generation of electr...

  7. Red or blue? A potential kilonova imprint of the delay until black hole formation following a neutron star merger

    CERN Document Server

    Metzger, Brian D


    Mergers of binary neutron stars (NSs) usually result in the formation of a hypermassive neutron star (HMNS). Whether- and when this remnant collapses to a black hole (BH) depends primarily on the equation of state and on angular momentum transport processes, both of which are uncertain. Here we show that the lifetime of the merger remnant may be directly imprinted in the radioactively powered kilonova emission following the merger. We employ axisymmetric, time-dependent hydrodynamic simulations of remnant accretion disks orbiting a HMNS of variable lifetime, and characterize the effect of this delay to BH formation on the disk wind ejecta. Our models follow the system evolution over several seconds, and include the effect of nuclear recombination, viscous heating, and neutrino irradiation by both the HMNS and the disk. When BH formation is relatively prompt ( 140, resulting in ~week-long emission with a spectral peak in the near-infrared (NIR), similar to that produced by the dynamical ejecta. In contrast, de...

  8. A Comparison of national CCS strategies for Northwest Europe, with a focus on the potential of common CO2 storage at the Utsira formation

    DEFF Research Database (Denmark)

    Ramirez, Andrea; Hoefnagels, Ric; van den Broek, Machteld


    2 storage. However, this will not only depend on their potential available capacity to store CO2 flows but also on the cost effectiveness of such an option within national portfolios of mitigation measures. This article shows key results of a research project aiming to assess the potentials...... in the national portfolio of measures. Within the CCS portfolio, storage of CO2 in the Utsira formation can indeed be a cost effective option for North Europe and it represents a valuable CO2 storage option at the regional level. For instance, the United Kingdom will profit from the comparably short transport...

  9. The Salient Map Analysis for Research and Teaching (SMART) method: Powerful potential as a formative assessment in the biomedical sciences (United States)

    Cathcart, Laura Anne

    This dissertation consists of two studies: 1) development and characterization of the Salient Map Analysis for Research and Teaching (SMART) method as a formative assessment tool and 2) a case study exploring how a paramedic instructor's beliefs about learners affect her utilization of the SMART method and vice versa. The first study explored: How can a novel concept map analysis method be designed as an effective formative assessment tool? The SMART method improves upon existing concept map analysis methods because it does not require hierarchically structured concept maps and it preserves the rich content of the maps instead of reducing each map down to a numerical score. The SMART method is performed by comparing a set of students' maps to each other and to an instructor's map. The resulting composite map depicts, in percentages and highlighted colors, the similarities and differences between all of the maps. Some advantages of the SMART method as a formative assessment tool include its ability to highlight changes across time, problematic or alternative conceptions, and patterns of student responses at a glance. Study two explored: How do a paramedic instructor's beliefs about students and learning affect---and become affected by---her use of the SMART method as a formative assessment tool? This case study of Angel, an expert paramedic instructor, begins to address a gap in the emergency medical services (EMS) education literature, which contains almost no research on teachers or pedagogy. Angel and I worked together as participant co-researchers (Heron & Reason, 1997) exploring the affordances of the SMART method. This study, based on those interactions with Angel, involved using open coding to identify themes (Strauss & Corbin, 1998) from Angel's views of students and use of the SMART method. Angel views learning as a sense-making process. She has a multi-faceted view of her students as novices and invests substantial time trying to understand their concept

  10. A whiff of nebular gas in Titan's atmosphere - Potential implications for the conditions and timing of Titan's formation (United States)

    Glein, Christopher R.


    In situ data from the GCMS instrument on the Huygens probe indicate that Titan's atmosphere contains small amounts of the primordial noble gases 36Ar and 22Ne (tentative detection), but it is unknown how they were obtained by the satellite. Based on the apparent similarity in the 22Ne/36Ar (atom) ratio between Titan's atmosphere and the solar composition, a previously neglected hypothesis for the origin of primordial noble gases in Titan's atmosphere is suggested - these species may have been acquired near the end of Titan's formation, when the moon could have gravitationally captured some nebular gas that would have been present in its formation environment (the Saturnian subnebula). These noble gases may be remnants of a primary atmosphere. This could be considered the simplest hypothesis to explain the 22Ne/36Ar ratio observed at Titan. However, the 22Ne/36Ar ratio may not be exactly solar if these species can be fractionated by external photoevaporation in the solar nebula, atmospheric escape from Titan, or sequestration on the surface of Titan. While the GCMS data are consistent with a 22Ne/36Ar ratio of 0.05 to 2.5 times solar (1σ range), simple estimates that attempt to account for some of the effects of these evolutionary processes suggest a sub-solar ratio, which may be depleted by approximately one order of magnitude. Models based on capture of nebular gas can explain why the GCMS did not detect any other primordial noble gas isotopes, as their predicted abundances are below the detection limits (especially for 84Kr and 132Xe). It is also predicted that atmospheric Xe on Titan should be dominated by radiogenic 129Xe if the source of primordial Xe is nebular gas. Of order 10-2-10-1 bar of primordial H2 may have been captured along with the noble gases from a gas-starved disk, but this H2 would have quickly escaped from the initial atmosphere. To have the opportunity to capture nebular gas, Titan should have formed within ∼10 Myr of the formation of the

  11. Vanishing linear term in chemical potential difference in volume term of work of critical nucleus formation for phase transition without volume change

    CERN Document Server

    Mori, Atsushi


    A question is given on the form n({\\mu}_{\\beta}-{\\mu}_{\\alpha}) for the volume term of work of formation of critical nucleus. Here, n is the number of molecule undergone the phase transition, {\\mu} denotes the chemical potential, {\\alpha} and {\\beta} represent the parent and nucleating phases, respectively. In this paper we concentrate phase transition without volume change. We have calculated the volume term in terms of the chemical potential difference {\\mu}_{re}-{\\mu}_{eq}$ for this case. Here, {\\mu}_{re} is the chemical potential of the reservoir and {\\mu}_{eq} that at the phase transition. We have W_{vol} = -[({\\kappa}_{\\beta}-{\\kappa}_{\\alpha})/(2v_{eq}^2)] ({\\mu}_{re}-{\\mu}_{eq})^2 V_{\\beta} with {\\kappa} denoting the isothermal compressibility, v_{eq} being the molecular volume at the phase transition, V_{\\beta} the volume of the nucleus.

  12. Vitamin B1-deficient mice show impairment of hippocampus-dependent memory formation and loss of hippocampal neurons and dendritic spines: potential microendophenotypes of Wernicke–Korsakoff syndrome (United States)

    Inaba, Hiroyoshi; Kishimoto, Takuya; Oishi, Satoru; Nagata, Kan; Hasegawa, Shunsuke; Watanabe, Tamae; Kida, Satoshi


    Patients with severe Wernicke–Korsakoff syndrome (WKS) associated with vitamin B1 (thiamine) deficiency (TD) show enduring impairment of memory formation. The mechanisms of memory impairment induced by TD remain unknown. Here, we show that hippocampal degeneration is a potential microendophenotype (an endophenotype of brain disease at the cellular and synaptic levels) of WKS in pyrithiamine-induced thiamine deficiency (PTD) mice, a rodent model of WKS. PTD mice show deficits in the hippocampus-dependent memory formation, although they show normal hippocampus-independent memory. Similarly with WKS, impairments in memory formation did not recover even at 6 months after treatment with PTD. Importantly, PTD mice exhibit a decrease in neurons in the CA1, CA3, and dentate gyrus (DG) regions of the hippocampus and reduced density of wide dendritic spines in the DG. Our findings suggest that TD induces hippocampal degeneration, including the loss of neurons and spines, thereby leading to enduring impairment of hippocampus-dependent memory formation. PMID:27576603

  13. Potential of Electrical Resistivity Tomography to Detect Fault Zones in Limestone and Argillaceous Formations in the Experimental Platform of Tournemire, France (United States)

    Gélis, C.; Revil, A.; Cushing, M. E.; Jougnot, D.; Lemeille, F.; Cabrera, J.; de Hoyos, A.; Rocher, M.


    The Experimental platform of Tournemire (Aveyron, France) developed by IRSN (French Institute for Radiological Protection and Nuclear Safety) is located in a tunnel excavated in a clay-rock formation interbedded between two limestone formations. A well-identified regional fault crosscuts this subhorizontal sedimentary succession, and a subvertical secondary fault zone is intercepted in the clay-rock by drifts and boreholes in the tunnel at a depth of about 250 m. A 2D electrical resistivity survey was carried out along a 2.5 km baseline, and a takeout of 40 m was used to assess the potential of this method to detect faults from the ground surface. In the 300 m-thick zone investigated by the survey, electrical resistivity images reveal several subvertical low-resistivity discontinuities. One of these discontinuities corresponds to the position of the Cernon fault, a major regional fault. One of the subvertical conductive discontinuities crossing the upper limestone formation is consistent with the prolongation towards the ground surface of the secondary fault zone identified in the clay-rock formation from the tunnel. Moreover, this secondary fault zone corresponds to the upward prolongation of a subvertical fault identified in the lower limestone using a 3D high-resolution seismic reflection survey. This type of large-scale electrical resistivity survey is therefore a useful tool for identifying faults in superficial layers from the ground surface and is complementary to 3D seismic reflection surveys.

  14. Vitamin B1-deficient mice show impairment of hippocampus-dependent memory formation and loss of hippocampal neurons and dendritic spines: potential microendophenotypes of Wernicke-Korsakoff syndrome. (United States)

    Inaba, Hiroyoshi; Kishimoto, Takuya; Oishi, Satoru; Nagata, Kan; Hasegawa, Shunsuke; Watanabe, Tamae; Kida, Satoshi


    Patients with severe Wernicke-Korsakoff syndrome (WKS) associated with vitamin B1 (thiamine) deficiency (TD) show enduring impairment of memory formation. The mechanisms of memory impairment induced by TD remain unknown. Here, we show that hippocampal degeneration is a potential microendophenotype (an endophenotype of brain disease at the cellular and synaptic levels) of WKS in pyrithiamine-induced thiamine deficiency (PTD) mice, a rodent model of WKS. PTD mice show deficits in the hippocampus-dependent memory formation, although they show normal hippocampus-independent memory. Similarly with WKS, impairments in memory formation did not recover even at 6 months after treatment with PTD. Importantly, PTD mice exhibit a decrease in neurons in the CA1, CA3, and dentate gyrus (DG) regions of the hippocampus and reduced density of wide dendritic spines in the DG. Our findings suggest that TD induces hippocampal degeneration, including the loss of neurons and spines, thereby leading to enduring impairment of hippocampus-dependent memory formation.

  15. Assessment of Groundwater Quality of Outer Skirts of Kota City with Reference to its Potential of Scale Formation and Corrosivity

    Directory of Open Access Journals (Sweden)

    Nitin Gupta


    Full Text Available Kota City is a prominent industrial and educational town of Rajasthan state, India. Mega industrial projects of cement, fertilizers, power plant, oil seed processing units are located nearby the city. The groundwater of study area is used in domestic as well as in industrial activities. It is worthwhile to know the water quality status and its effect on entity, which is exposed in practical use. A comprehensive assessment of water quality parameters in groundwater samples drawn from 24 different locations, 6 sites from each direction at outer skirts of Kota City of Rajasthan, India, in four seasons of years 2006 to 2008 was carried out. To find out the suitability and stability of water, various indices available to assess the scale formation and corrosivity was used. The Langelier saturation index (LSI and Ryznar saturation index (RSI were calculated and discussed with respect to saturation level.

  16. Investigation of in-situ electrode formation with respect to potential applications in intermediate temperature solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Qingping


    The novel SEA (Single Element Arrangement) concept for SOFC consists of a single material to complete the whole galvanic cell. Essential of the SEA concept is the in-situ electrode formation. Such kind of material becomes mixed ionic and electronic conducting in the surface region, while still being predominantly ionically conducting inside under the working conditions. Electronic short circuit will be blocked by the region where ionic conduction is dominant, allowing the generation of electromotive force. In this work, several materials that were considered to be possible candidates for SEA applications were investigated, with the focus on modification of the electronic conductivity by appropriate doping in the well-known electrolyte materials, including samarium doped ceria (SDC), yttria doped barium cerate and LSGM. (orig.)

  17. The Archean kalsilite-nepheline syenites of the Awsard intrusive massif (Reguibat Shield, West African Craton, Morocco) and its relationship to the alkaline magmatism of Africa (United States)

    Haissen, Faouziya; Cambeses, Aitor; Montero, Pilar; Bea, Fernando; Dilek, Yildirim; Mouttaqi, Abdellah


    More than 40% of the known alkaline complexes are reported from Africa. Most are ring complexes composed of syenites and associated or not, lithotypes as carbonatites, granites and mafic rocks. Radiometric dating indicates the presence of alkaline complexes with ages spanning from Precambrian to the present. In terms of outcrops, alkaline complexes are reported from cratonic zones and from belts embedded between cratonic areas. Because of the high economic potential for associated REE deposits, these alkaline complexes have received much attention from Earth scientists. These studies aim mainly to constrain the role of the mantle and the crust (and the interaction between them) in the genesis of this peculiar magmatism, and also to explain the variability observed in lithotypes and geotectonic settings. Among those alkaline complexes, Precambrian occurrences are rare. Up-to-date only a few Proterozoic examples were cited in Africa. The recently studied Awsard complex in Southern Morocco is a peculiar one with a crystallization age of 2.46 Ga and an unusual rock assemblages. This paper is a first approximation to a comparison of geochemical and isotopic fingerprints of the Awsard magmatism (as the oldest one) with other known different ages African complexes from different geotectonic settings, aiming to detect if there is any evolution in this alkaline magmatism through time. A first conclusion is that magma sources for this alkaline magmatism has been probably evaluating over geological time, from parental magmas compositions close to that of primitive mantle in these early geological time to compositions holding more and more depleted mantle and continental crust components. However, to go further in this debate more modern isotopic, geochemical and geochronological data from all these complexes are needed. Nevertheless, this comparison highlighted the peculiar character of the Awsard magmatism with an isotopic composition very close to that of Primitive mantle

  18. Glass Formation of n-Butanol: Coarse-grained Molecular Dynamics Simulations Using Gay-Berne Potential Model

    Institute of Scientific and Technical Information of China (English)

    Gui-long Xie; Yong-hong Zhang; Shi-ping Huang


    Using coarse-grained molecular dynamics simulations based on Gay-Berne potential model,we have simulated the cooling process of liquid n-butanol.A new set of GB parameters are obtained by fitting the results of density functional theory calculations.The simulations are carried out in the range of 290-50 K with temperature decrements of 10 K.The cooling characteristics are determined on the basis of the variations of the density,the potential energy and orientational order parameter with temperature,whose slopes all show discontinuity.Both the radial distribution function curves and the second-rank orientational correlation function curves exhibit splitting in the second peak.Using the discontinuous change of these thermodynamic and structure properties,we obtain the glass transition at an estimate of temperature Tg=120±10 K,which is in good agreement with experimental results 110±1 K.

  19. Assessing the Potential for Bioremediation through Formation and Fate of Metal Rich Granules in the Terrestrial Environment (United States)


    on earthworms Nanomaterials Fate and ecotoxicology of nanomaterials Aquatic Toxicology Long-term exposure to explosives Biomimetics of contaminant...bioavailability Impact of climate change to aquatic invertebrates Risk of contaminated sediment  5,000 sq ft: ► culture facility ► toxicology...surface waters – Groundwater • Potential for extensive impact to both aquatic and terrestrial organisms from Pb contaminated Army ranges Impact of Pb

  20. Formation mechanism of propagated sensation along the meridians, as verified by cortical somatosensory-evoked potential topographic maps

    Institute of Scientific and Technical Information of China (English)

    Jinsen Xu; Xiaohua Pan; Shuxia Zheng; Xianglong Hu; Zheyan Sa


    The peripheral driver stimulating theory states that as a driver passes along a certain meridian during acupuncture; the driver provokes nerve sense devices along the meridian, resulting in the nerve impulse entering the central nervous system. Accordingly, volunteers have reported propagated sensations along the meridians (PSM). The present study was designed to utilize a cortical somatosensory-evoked potential (CSEP) topographic map for determining whether stimulation expansion occurs in somatosensory area I when sensation was provoked in individuals with obvious PSM. The sensation was blocked by mechanical compression, and the sensation was imitated in individuals without PSM. Results revealed a red, high-potential signal in the representative area of the lower limbs in individuals with obvious PSM symptoms when the Gall Bladder Meridian (GBM) sensation passed to the head and face. This representative area was near the middle line of the CSEP topographic map, and a red, high-potential signal, which jumps over the representative area of the upper limbs, also appeared in the representative face area, which was at the external region of the CSEP topographic map. However, in individuals exhibiting no PSM, only a red high-potential signal appeared in the representative lower limb area. When Hegu (LI 4) was stimulated in individuals without PSM, an obvious evoked response appeared only in the representative upper limb area. However, when Hegu was stimulated in individuals exhibiting PSM, the response area was larger in the representative upper limb area and extended to the representative face area. When Guangming (GB 37) was stimulated in PSM individuals, the face representation response disappeared and was confined to a foot representation of the somatosensory area I when PSM was blocked by mechanical pressure. Results suggested that mechanical compression blocked PSM, and corresponding changes were exhibited in the CSEP topographic map. These results provide

  1. Emission characteristics of volatile organic compounds and their secondary organic aerosol formation potentials from a petroleum refinery in Pearl River Delta, China. (United States)

    Zhang, Zhijuan; Wang, Hao; Chen, Dan; Li, Qinqin; Thai, Phong; Gong, Daocheng; Li, Yang; Zhang, Chunlin; Gu, Yinggang; Zhou, Lei; Morawska, Lidia; Wang, Boguang


    A campaign was carried out to measure the emission characteristics of volatile organic compounds (VOCs) in different areas of a petroleum refinery in the Pearl River Delta (PRD) region in China. In the refining area, 2-methylpentane, 2,3-dimethylbutane, methylcyclopentane, 3-methylhexane, and butane accounted for >50% of the total VOCs; in the chemical industry area, 2-methylpentane, p-diethylbenzene, 2,3-dimethylbutane, m-diethylbenzene and 1,2,4-trimethylbenzene were the top five VOCs detected; and in the wastewater treatment area, the five most abundant species were 2-methylpentane, 2,3-dimethylbutane, methylcyclopentane, 3-methylpentane and p-diethylbenzene. The secondary organic aerosol (SOA) formation potential was estimated using the fractional aerosol coefficients (FAC), secondary organic aerosol potential (SOAP), and SOA yield methods. The FAC method suggests that toluene, p-diethylbenzene, and p-diethylbenzene are the largest contributors to the SOA formation in the refining, chemical industry, and wastewater treatment areas, respectively. With the SOAP method, it is estimated that toluene is the largest contributor to the SOA formation in the refining area, but o-ethyltoluene contributes the most both in the chemical industry and wastewater treatment areas. For the SOA yield method, aromatics dominate the yields and account for nearly 100% of the total in the three areas. The SOA concentrations estimated of the refining, chemical industry and wastewater treatment areas are 30, 3835 and 137μgm(-3), respectively. Despite the uncertainties and limitations associated with the three methods, the SOA yield method is suggested to be used for the estimation of SOA formation from the petroleum refinery. The results of this study have demonstrated that the control of VOCs, especially aromatics such as toluene, ethyltoluene, benzene and diethylbenzene, should be a focus of future regulatory measures in order to reduce PM pollution in the PRD region.

  2. Evaluation of disinfection by-product formation potential (DBPFP) during chlorination of two algae species--Blue-green Microcystis aeruginosa and diatom Cyclotella meneghiniana. (United States)

    Liao, Xiaobin; Liu, Jinjin; Yang, Mingli; Ma, Hongfang; Yuan, Baoling; Huang, Ching-Hua


    Microcystis aeruginosa (blue-green alga) commonly blooms in summer and Cyclotella meneghiniana (diatom) outbreaks in fall in the reservoirs that serve as drinking water sources in Southeast China. Herein, an evaluation of disinfection by-product formation potential (DBPFP) from them during chlorination should be conducted. Five DBPs including trichloromethane (TCM), trichloronitromethane (TCNM), dichloroacetonitrile (DCAN), 1,1-dichloropropanone (1,1-DCP) and 1,1,1-trichloropropanone (1,1,1-TCP) were monitored. The formation potential of TCM and TCNM was enhanced with the increase of reaction time and chlorine dosage, whereas that of DCAN, 1,1-DCP and 1,1,1-TCP increased first and then fell with continuing reaction time. M. aeruginosa showed higher DBPFP than C. meneghiniana, the yield of DBPs varied with components of algal cells. The DBPFP order from components of M. aeruginosa was cell suspension (CS) ≈ intracellular organic matter (IOM) > extracellular organic matter (EOM) > cell debris (CD), which indicated that IOM was the main DBP precursors for M. aeruginosa. The yields of DBPs from components of C. meneghiniana were in the order of CS>IOM≈ CD ≈ EOM, suggesting that three components made similar contributions to the total DBP formation. The amount of IOM with higher DBPFP leaked from both algae species increased with the chlorine dosage, indicating that chlorine dosage should be considered carefully in the treatment of eutrophic water for less destroying of the cell integrity. Though fluorescence substances contained in both algae species varied significantly, the soluble microbial products (SMPs) and aromatic protein-like substances were the main cellular components that contributed to DBP formation for both algae.

  3. The effect of UV/H2O2 treatment on disinfection by-product formation potential under simulated distribution system conditions. (United States)

    Metz, D H; Meyer, M; Dotson, A; Beerendonk, E; Dionysiou, D D


    Advanced oxidation with ultraviolet light and hydrogen peroxide (UV/H(2)O(2)) produces hydroxyl radicals that have the potential to degrade a wide-range of organic micro-pollutants in water. Yet, when this technology is used to reduce target contaminants, natural organic matter can be altered. This study evaluated disinfection by-product (DBP) precursor formation for UV/H(2)O(2) while reducing trace organic contaminants in natural water (>90% for target pharmaceuticals, pesticides and taste and odor producing compounds and 80% atrazine degradation). A year-long UV/H(2)O(2) pilot study was conducted to evaluate DBP precursor formation with varying water quality. The UV pilot reactors were operated to consistently achieve 80% atrazine degradation, allowing comparison of low pressure (LP) and medium pressure (MP) lamp technologies for DBP precursor formation. Two process waters of differing quality were used as pilot influent, i.e., before and after granular activated carbon adsorption. DBP precursors increased under most of the conditions studied. Regulated trihalomethane formation potential increased through the UV/H(2)O(2) reactors from 20 to 118%, depending on temperature and water quality. When Post-GAC water served as reactor influent, less DBPs were produced in comparison to conventionally treated water. Haloacetic acid (HAA5) increased when conventionally treated water served as UV/H(2)O(2) pilot influent, but only increased slightly (MP lamp) when GAC treated water served as pilot influent. No difference in 3-day simulated distribution system DBP concentration was observed between LP and MP UV reactors when 80% atrazine degradation was targeted.

  4. The Gibbs free energy of formation of halogenated benzenes, benzoates and phenols and their potential role as electron acceptors in anaerobic environments. (United States)

    Dolfing, Jan; Novak, Igor


    The sequence of redox reactions in the natural environment generally follows the electron affinity of the electron acceptors present and can be rationalized by the redox potentials of the appropriate half-reactions. Answering the question how halogenated aromatics fit into this sequence requires information on their Gibbs free energy of formation values. In 1992 Gibbs free energy data for various classes of halogenated aromatic compounds were systematically explored for the first time based on Benson's group contribution method. Since then more accurate quantum chemical calculation methods have become available. Here we use these methods to estimate enthalpy and Gibbs free energy of formation values of all chlorinated and brominated phenols. These data and similar state-of-the-art datasets for halogenated benzenes and benzoates were then used to calculate two-electron redox potentials of halogenated aromatics for standard conditions and for pH 7. The results underline the need to take speciation into consideration when evaluating redox potentials at pH 7 and highlight the fact that halogenated aromatics are excellent electron acceptors in aqueous environments.

  5. Influence of fuel ethanol content on primary emissions and secondary aerosol formation potential for a modern flex-fuel gasoline vehicle (United States)

    Timonen, Hilkka; Karjalainen, Panu; Saukko, Erkka; Saarikoski, Sanna; Aakko-Saksa, Päivi; Simonen, Pauli; Murtonen, Timo; Dal Maso, Miikka; Kuuluvainen, Heino; Bloss, Matthew; Ahlberg, Erik; Svenningsson, Birgitta; Pagels, Joakim; Brune, William H.; Keskinen, Jorma; Worsnop, Douglas R.; Hillamo, Risto; Rönkkö, Topi


    The effect of fuel ethanol content (10, 85 and 100 %) on primary emissions and on subsequent secondary aerosol formation was investigated for a Euro 5 flex-fuel gasoline vehicle. Emissions were characterized during a New European Driving Cycle (NEDC) using a comprehensive set-up of high time-resolution instruments. A detailed chemical composition of the exhaust particulate matter (PM) was studied using a soot particle aerosol mass spectrometer (SP-AMS), and secondary aerosol formation was studied using a potential aerosol mass (PAM) chamber. For the primary gaseous compounds, an increase in total hydrocarbon emissions and a decrease in aromatic BTEX (benzene, toluene, ethylbenzene and xylenes) compounds was observed when the amount of ethanol in the fuel increased. In regard to particles, the largest primary particulate matter concentrations and potential for secondary particle formation was measured for the E10 fuel (10 % ethanol). As the ethanol content of the fuel increased, a significant decrease in the average primary particulate matter concentrations over the NEDC was found. The PM emissions were 0.45, 0.25 and 0.15 mg m-3 for E10, E85 and E100, respectively. Similarly, a clear decrease in secondary aerosol formation potential was observed with a larger contribution of ethanol in the fuel. The secondary-to-primary PM ratios were 13.4 and 1.5 for E10 and E85, respectively. For E100, a slight decrease in PM mass was observed after the PAM chamber, indicating that the PM produced by secondary aerosol formation was less than the PM lost through wall losses or the degradation of the primary organic aerosol (POA) in the chamber. For all fuel blends, the formed secondary aerosol consisted mostly of organic compounds. For E10, the contribution of organic compounds containing oxygen increased from 35 %, measured for primary organics, to 62 % after the PAM chamber. For E85, the contribution of organic compounds containing oxygen increased from 42 % (primary) to 57

  6. Assessment of the role of circulating breast cancer cells in tumor formation and metastatic potential using in vivo flow cytometry (United States)

    Hwu, Derrick; Boutrus, Steven; Greiner, Cherry; Dimeo, Theresa; Kuperwasser, Charlotte; Georgakoudi, Irene


    The identification of breast cancer patients who will ultimately progress to metastatic disease is of significant clinical importance. The quantification and assessment of circulating tumor cells (CTCs) has been proposed as one strategy to monitor treatment effectiveness and disease prognosis. However, CTCs have been an elusive population of cells to study because of their small number and difficulties associated with isolation protocols. In vivo flow cytometry (IVFC) can overcome these limitations and provide insights in the role these cells play during primary and metastatic tumor growth. In this study, we used two-color IVFC to examine, for up to ten weeks following orthotopic implantation, changes in the number of circulating human breast cells expressing GFP and a population of circulating hematopoietic cells with strong autofluorescence. We found that the number of detected CTCs in combination with the number of red autofluorescent cells (650 to 690 nm) during the first seven days following implantation was predictive in development of tumor formation and metastasis eight weeks later. These results suggest that the combined detection of these two cell populations could offer a novel approach in the monitoring and prognosis of breast cancer progression, which in turn could aid significantly in their effective treatment.

  7. The formation of potentially harmful compounds in churros, a Spanish fried-dough pastry, as influenced by deep frying conditions. (United States)

    Morales, F J; Arribas-Lorenzo, G


    Colour, moisture, hydroxymethylfurfural (HMF) and acrylamide (AA) were investigated in traditional Spanish churros. Samples were deep-fried in sunflower oil at lab-scale temperatures of 180, 190 and 200°C and for frying times of 2, 3, 5 and 7min. Fresh made churros were also obtained from local producers. HMF ranged from 1.2±0.02 to 221.4±2.02mg/kg for lab-scale experiments and an average of 74.3±47.5mg/kg was recorded in commercial samples. AA ranged from below the limit of quantitation to 90±0.6μg/kg for lab-scale experiments and an average of 46±24.5μg/kg was measured in commercial samples. Temperatures between 185 and 200°C are commonly used to obtain churros with an acceptable palatability and a crispy surface. However, HMF and AA levels increased nearly two-fold from 190 to 200°C at the same frying times, indicating that a more precise control of frying temperatures is required to minimize their formation.

  8. Characterization of Natural Organic Matter and Disinfection Byproducts Formation Potential in Pilot-Scale Coagulation-Ultrafiltration Membrane Combined Process in Winter

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yaozong; WANG Qishan; HE Fenghua; DING Shasha


    A pilot-scale ultrafiltration membrane plant was set up for treating Luanhe River water with flocculating and precipitation process of waterworks. The aim is to investigate the variation and characteristics of natural organic matter and disinfection byproducts formation potential in the whole process in winter. The results show that dissolved organic matter (DOM), UV254, trihaiomethanes formation potential (THMsFP) and haloacetic acids formation poten-tial (HAAsFP) of Luanhe River water were mainly distributed in the range of molecular weight (MW) <1 kDa, so were the membrane feed water and treated water by membrane. Specifc UV absorbance, specific THMsFP and spe-cific HAAsFP have the maximal value in the MW fraction of 1-3 kDa, except that specific UV absorbance of mem-brane feed water is in the range of 3-10 kDa; DOM of membrane backwash water is mainly distributed in the range of MW30 kDa and MW<1 kDa. It is the DOM in water backwashing in up way that made significant contribution to the higher dissolved organic carbon content in membrane backwash water. However, UV254, THMsFP and HAAsFP were mainly distributed in the range of MW<1 kDa. The highest concentrations of specific THMsFP and specific HAAsFP appeared in the MW fraction of 3-10 kDa. CHCl3 was the major THMs species during MBW chlorination and occupied more than 60% of the total THMsFP. Dichloroacetic acid and trichloroacetic acid were the main compo-nents in HAAsFP. The concentration of THMsFP and HAAsFP in MBW was influenced by operation period.

  9. BioMig--A Method to Evaluate the Potential Release of Compounds from and the Formation of Biofilms on Polymeric Materials in Contact with Drinking Water. (United States)

    Wen, Gang; Kötzsch, Stefan; Vital, Marius; Egli, Thomas; Ma, Jun


    In contact with water, polymeric materials (plastics) release compounds that can support suspended microbial growth and/or biofilm formation. The different methods presently used in the European Union to test plastics take 7-16 weeks to obtain a result. In industry, this delays material and product development as well as quality testing. Therefore, we developed a method package (BioMig) that allows testing of plastic materials with high reproducibility in 2 weeks for their potential biofilm (or biomass) formation and release of carbonaceous migration products when in contact with water. BioMig consists of (i) an extended migration potential test (seven times for 24 h at 60 °C), based on the European norm EN 12873-1 and the German UBA (Umweltbundesamt) guideline, and (ii) a biomass formation potential (BFP) test (14 days at 30 °C), which is a modified version of the Dutch biofilm production potential test. In the migration potential test, the amount of carbon released into water by the specimen is quantified by monitoring total and assimilable organic carbon over time; furthermore, the modular design of the test also allows one to assess additional parameters such as pathogen growth potential on the migration water or toxic effects on microbial growth. Flow cytometry (FCM)-based total cell counting (TCC) is used to quantify microbial growth in suspension and on surfaces after removal with mild sonication without affecting cell integrity. The BFP test allows one to determine both the planktonic (pBFP) and the sessile (sBFP) cell fractions. The sBFP consists of surface-attached cells after removal (>90% efficiency). Results for four standard test materials (PE-Xa, PE-Xc, EPDM 2%, and EPDM 20%), plus positive (PVC-P) and negative (glass) controls are presented. FCM-based TCC demonstrates that the release of growth-supporting carbon and proliferation of surface-attached cells stops increasing and stabilizes after 14 days of incubation; this allows for faster

  10. Batievaite-(Y), Y2Ca2Ti[Si2O7]2(OH)2(H2O)4, a new mineral from nepheline syenite pegmatite in the Sakharjok massif, Kola Peninsula, Russia (United States)

    Lyalina, L. M.; Zolotarev, A. A.; Selivanova, E. A.; Savchenko, Ye. E.; Krivovichev, S. V.; Mikhailova, Yu. A.; Kadyrova, G. I.; Zozulya, D. R.


    Batievaite-(Y), Y2Ca2Ti[Si2O7]2(OH)2(H2O)4, is a new mineral found in nepheline syenite pegmatite in the Sakharjok alkaline massif, Western Keivy, Kola Peninsula, Russia. The pegmatite mainly consists of nepheline, albite, alkali pyroxenes, amphiboles, biotite and zeolites. Batievaite-(Y) is a late-pegmatitic or hydrothermal mineral associated with meliphanite, fluorite, calcite, zircon, britholite-group minerals, leucophanite, gadolinite-subgroup minerals, titanite, smectites, pyrochlore-group minerals, zirkelite, cerianite-(Ce), rutile, behoite, ilmenite, apatite-group minerals, mimetite, molybdenite, and nickeline. Batievaite-(Y) is pale-cream coloured with white streak and dull, greasy or pearly luster. Its Mohs hardness is 5-5.5. No cleavage or parting was observed. The measured density is 3.45(5) g/cm3. Batievaite-(Y) is optically biaxial positive, α 1.745(5), β 1.747(5), γ 1.752(5) (λ 589 nm), 2 V meas. = 60(5)°, 2 V calc. = 65°. Batievaite-(Y) is triclinic, space group P-1, a 9.4024(8), b 5.5623(5), c 7.3784(6) Å, α 89.919(2), β 101.408(2), γ 96.621(2)°, V 375.65(6) Å3 and Z = 1. The eight strongest lines of the X-ray powder diffraction pattern [ d(Å)(I)( hkl)] are: 2.991(100)(11-2), 7.238(36)(00-1), 3.061(30)(300), 4.350(23)(0-1-1), 9.145(17)(100), 4.042(16)(11-1), 2.819(16)(3-10), 3.745(13)(2-10). The chemical composition determined by electron probe microanalysis (EPMA) is (wt.%): Nb2O5 2.25, TiO2 8.01, ZrO2 2.72, SiO2 29.96, Al2O3 0.56, Fe2O3 0.43, Y2O3 11.45, La2O3 0.22, Ce2O3 0.33, Nd2O3 0.02, Gd2O3 0.07, Dy2O3 0.47, Er2O3 1.07, Tm2O3 0.25, Yb2O3 2.81, Lu2O3 0.45, CaO 24.98, MnO 1.31, MgO 0.01, Na2O 1.13, K2O 0.02, F 2.88, Cl 0.19, H2O 6.75 (determined on the basis of crystal structure data), O = (F,Cl) -1.25, total 97.09 wt.%. The empirical formula based on the EPMA and single-crystal structure analyses is (Y0.81Ca0.65Mn0.15Zr0.12Yb0.11Er0.04Fe3+ 0.04Ce0.02Dy0.02Lu0.02La0.01Tm0.01)Σ2.00((H2O)0.75Ca0.70□0.55)Σ2.00Ca2.00(□0.61Na0

  11. Batievaite-(Y), Y2Ca2Ti[Si2O7]2(OH)2(H2O)4, a new mineral from nepheline syenite pegmatite in the Sakharjok massif, Kola Peninsula, Russia (United States)

    Lyalina, L. M.; Zolotarev, A. A.; Selivanova, E. A.; Savchenko, Ye. E.; Krivovichev, S. V.; Mikhailova, Yu. A.; Kadyrova, G. I.; Zozulya, D. R.


    Batievaite-(Y), Y2Ca2Ti[Si2O7]2(OH)2(H2O)4, is a new mineral found in nepheline syenite pegmatite in the Sakharjok alkaline massif, Western Keivy, Kola Peninsula, Russia. The pegmatite mainly consists of nepheline, albite, alkali pyroxenes, amphiboles, biotite and zeolites. Batievaite-(Y) is a late-pegmatitic or hydrothermal mineral associated with meliphanite, fluorite, calcite, zircon, britholite-group minerals, leucophanite, gadolinite-subgroup minerals, titanite, smectites, pyrochlore-group minerals, zirkelite, cerianite-(Ce), rutile, behoite, ilmenite, apatite-group minerals, mimetite, molybdenite, and nickeline. Batievaite-(Y) is pale-cream coloured with white streak and dull, greasy or pearly luster. Its Mohs hardness is 5-5.5. No cleavage or parting was observed. The measured density is 3.45(5) g/cm3. Batievaite-(Y) is optically biaxial positive, α 1.745(5), β 1.747(5), γ 1.752(5) (λ 589 nm), 2V meas. = 60(5)°, 2V calc. = 65°. Batievaite-(Y) is triclinic, space group P-1, a 9.4024(8), b 5.5623(5), c 7.3784(6) Å, α 89.919(2), β 101.408(2), γ 96.621(2)°, V 375.65(6) Å3 and Z = 1. The eight strongest lines of the X-ray powder diffraction pattern [d(Å)(I)(hkl)] are: 2.991(100)(11-2), 7.238(36)(00-1), 3.061(30)(300), 4.350(23)(0-1-1), 9.145(17)(100), 4.042(16)(11-1), 2.819(16)(3-10), 3.745(13)(2-10). The chemical composition determined by electron probe microanalysis (EPMA) is (wt.%): Nb2O5 2.25, TiO2 8.01, ZrO2 2.72, SiO2 29.96, Al2O3 0.56, Fe2O3 0.43, Y2O3 11.45, La2O3 0.22, Ce2O3 0.33, Nd2O3 0.02, Gd2O3 0.07, Dy2O3 0.47, Er2O3 1.07, Tm2O3 0.25, Yb2O3 2.81, Lu2O3 0.45, CaO 24.98, MnO 1.31, MgO 0.01, Na2O 1.13, K2O 0.02, F 2.88, Cl 0.19, H2O 6.75 (determined on the basis of crystal structure data), O = (F,Cl) -1.25, total 97.09 wt.%. The empirical formula based on the EPMA and single-crystal structure analyses is (Y0.81Ca0.65Mn0.15Zr0.12Yb0.11Er0.04Fe3+ 0.04Ce0.02Dy0.02Lu0.02La0.01Tm0.01)Σ2.00((H2O)0.75Ca0.70□0.55)Σ2.00Ca2.00(□0.61Na0.25( H2O

  12. Long-term potentiation and memory processes in the psychological works of Sigmund Freud and in the formation of neuropsychiatric symptoms. (United States)

    Centonze, D; Siracusano, A; Calabresi, P; Bernardi, G


    Far from disproving the model of mind functioning proposed by psychoanalysis, the recent advances in neuropsychiatrical research confirmed the crucial ideas of Sigmund Freud. The hypothesis that the origin of mental illnesses lies in the impossibility for a subject to erase the long-term effects of a remote adverse event is in tune with the view that several psychiatric disturbances reflect the activation of aberrant unconscious memory processes. Freud's insights did not stop here, but went on to describe in an extremely precise manner the neural mechanisms of memory formation almost a century before the description of long-term synaptic potentiation.

  13. Energy deposition by heavy ions: additivity of kinetic and potential energy contributions in hillock formation on CaF2. (United States)

    Wang, Y Y; Grygiel, C; Dufour, C; Sun, J R; Wang, Z G; Zhao, Y T; Xiao, G Q; Cheng, R; Zhou, X M; Ren, J R; Liu, S D; Lei, Y; Sun, Y B; Ritter, R; Gruber, E; Cassimi, A; Monnet, I; Bouffard, S; Aumayr, F; Toulemonde, M


    Modification of surface and bulk properties of solids by irradiation with ion beams is a widely used technique with many applications in material science. In this study, we show that nano-hillocks on CaF2 crystal surfaces can be formed by individual impact of medium energy (3 and 5 MeV) highly charged ions (Xe(22+) to Xe(30+)) as well as swift (kinetic energies between 12 and 58 MeV) heavy xenon ions. For very slow highly charged ions the appearance of hillocks is known to be linked to a threshold in potential energy (Ep) while for swift heavy ions a minimum electronic energy loss per unit length (Se) is necessary. With our results we bridge the gap between these two extreme cases and demonstrate, that with increasing energy deposition via Se the Ep-threshold for hillock production can be lowered substantially. Surprisingly, both mechanisms of energy deposition in the target surface seem to contribute in an additive way, which can be visualized in a phase diagram. We show that the inelastic thermal spike model, originally developed to describe such material modifications for swift heavy ions, can be extended to the case where both kinetic and potential energies are deposited into the surface.

  14. The formation of relativistic plasma structures and their potential role in the generation of cosmic ray electrons

    Directory of Open Access Journals (Sweden)

    M. E. Dieckmann


    Full Text Available Recent particle-in-cell (PIC simulation studies have addressed particle acceleration and magnetic field generation in relativistic astrophysical flows by plasma phase space structures. We discuss the astrophysical environments such as the jets of compact objects, and we give an overview of the global PIC simulations of shocks. These reveal several types of phase space structures, which are relevant for the energy dissipation. These structures are typically coupled in shocks, but we choose to consider them here in an isolated form. Three structures are reviewed. (1 Simulations of interpenetrating or colliding plasma clouds can trigger filamentation instabilities, while simulations of thermally anisotropic plasmas observe the Weibel instability. Both transform a spatially uniform plasma into current filaments. These filament structures cause the growth of the magnetic fields. (2 The development of a modified two-stream instability is discussed. It saturates first by the formation of electron phase space holes. The relativistic electron clouds modulate the ion beam and a secondary, spatially localized electrostatic instability grows, which saturates by forming a relativistic ion phase space hole. It accelerates electrons to ultra-relativistic speeds. (3 A simulation is also revised, in which two clouds of an electron-ion plasma collide at the speed 0.9c. The inequal densities of both clouds and a magnetic field that is oblique to the collision velocity vector result in waves with a mixed electrostatic and electromagnetic polarity. The waves give rise to growing corkscrew distributions in the electrons and ions that establish an equipartition between the electron, the ion and the magnetic energy. The filament-, phase space hole- and corkscrew structures are discussed with respect to electron acceleration and magnetic field generation.

  15. Formation and characterization of iron-binding phosphorylated human-like collagen as a potential iron supplement

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Jianjun; Chen, Fei; Fan, Daidi, E-mail:; Zhu, Chenhui; Ma, Xiaoxuan; Xue, Wenjiao


    Iron incorporated into food can induce precipitation and unwanted interaction with other components in food. Iron-binding proteins represent a possibility to avoid these problems and other side effects, as the iron is protected. However, there are several technical problems associated with protein–iron complex formation. In this paper, the iron-binding phosphorylated human-like collagen (Fe-G6P-HLC) was prepared under physiological conditions through phosphorylated modification. One molecule of Fe-G6P-HLC possesses about 24 atoms of Fe. Spectroscopy analysis, differential scanning calorimetry (DSC) and equilibrium dialysis techniques were employed to investigate the characteristics of the Fe-G6P-HLC. The binding sites (n{sub b}) and apparent association constant (K{sub app}) between iron and phosphorylated HLC were measured at n{sub b} = 23.7 and log K{sub app} = 4.57, respectively. The amount of iron (Fe{sup 2+} sulfate) binding to phosphorylated HLC was found to be a function of pH and phosphate content. In addition, the solubility and thermal stability of HLC were not significantly affected. The results should facilitate the utilization of HLC as a bioactive iron supplement in the food and medical industry and provide an important theoretical evidence for the application of HLC chelates. - Highlights: • The iron-binding phosphorylated human-like collagen (Fe-G6P-HLC) was prepared. • One molecule of Fe-G6P-HLC possesses about 24 atoms of Fe. • The binding properties could be modulated through alterations in pH and phosphate content presented in HLC. • A novel strategy for preparing iron-binding proteins was provided.

  16. Methanolic Extract of Dill Leaves Inhibits AGEs Formation and Shows Potential Hepatoprotective Effects in CCl4 Induced Liver Toxicity in Rat

    Directory of Open Access Journals (Sweden)

    Ebrahim Abbasi Oshaghi


    Full Text Available The research was aimed at evaluating the antiglycation, antioxidant, and hepatoprotective properties of methanolic extract of Anethum graveolens (dill. The antioxidant properties, photochemical characteristics, and antiglycation effects of dill extract were measured. Carbon tetrachloride-induced hepatotoxic rats were used to show the hepatoprotective activity of dill leaves. Different concentration of dill extract (0.032, 0.065, 0.125, 0.25, 0.5, and 1 mg/mL showed potential antioxidant ability. The extract of dill leaves significantly reduced AGEs formation and also fructosamine and protein carbonyl levels in rats’ liver. Thiol groups’ oxidation, amyloid cross-β, and protein fragmentation (P<0.001 significantly reduced in treated rats. Liver damage markers significantly reduced in dill-treated animals (P<0.05. Dill with potential antioxidant, antiglycation, and hepatoprotective effects can be suggested for treatment of diabetes complications.

  17. Contribution of harmonicity and location to auditory object formation in free field: Evidence from event-related brain potentials (United States)

    McDonald, Kelly L.; Alain, Claude


    The contribution of location and harmonicity cues in sound segregation was investigated using behavioral reports and source waveforms derived from the scalp-recorded evoked potentials. Participants were presented with sounds composed of multiple harmonics in a free-field environment. The third harmonic was either tuned or mistuned and could be presented from the same or different location from the remaining harmonics. Presenting the third harmonic at a different location than the remaining harmonics increased the likelihood of hearing the tuned or slightly (i.e., 2%) mistuned harmonic as a separate object. Partials mistuned by 16% of their original value ``pop out'' of the complex and were paralleled by an object-related negativity (ORN) that superimposed the N1 and P2 components. For the 2% mistuned stimuli, the ORN was present only when the mistuned harmonic was presented at a different location than the remaining harmonics. Presenting the tuned harmonic at a different location also yielded changes in neural activity between 150 and 250 ms after sound onset. The behavioral and electrophysiological results indicate that listeners can segregate sounds based on harmonicity or location alone. The results also indicate that a conjunction of harmonicity and location cues contribute to sound segregation primarily when harmonicity is ambiguous.

  18. Tablets of pre-liposomes govern in situ formation of liposomes: concept and potential of the novel drug delivery system. (United States)

    Vanić, Željka; Planinšek, Odon; Škalko-Basnet, Nataša; Tho, Ingunn


    The purpose of this study was to develop a novel drug delivery system for challenging drugs with potential for scale-up manufacturing and controlled release of incorporated drug. Pre-liposomes powder containing metronidazole, lecithin and mannitol, prepared by spray-drying, was mixed with different tableting excipients (microcrystalline cellulose, lactose monohydrate, mannitol, dibasic calcium phosphate, pregelatinized starch, pectin or chitosan) and compressed into tablets. The delivery system was characterized with respect to (i) dry powder characteristics, (ii) mechanical tablet properties and drug release, and (iii) liposomal characteristics. The pre-liposomes powder was free-flowing, and tablets of similarly high qualities as tablets made of physical mixtures were prepared with all excipients. Liposomes were formed in situ upon tablet disintegration, dissolution or erosion depending on the type of tablet excipient used. The liposomal characteristics and drug release were found to depend on the tablet excipient. The new delivery system offers a unique synergy between the ability of liposomes to encapsulate and protect drugs and increased stability provided by compressed formulations. It can be adjusted for drug administration via various routes, e.g. oral, buccal and vaginal.

  19. (68) Ga-Ca-phytate particles: A potential lung perfusion agent of synthetic origin prepared in a cold kit format. (United States)

    Hsieh, William; Ali, Masood; Praehofer, Renee; Tsopelas, Chris


    The objective of this study was to investigate the radiosynthesis of (68) Ga-Ca-phytate particles and then characterize the formulation for radiochemical purity, radioactive particle size distribution, and biodistribution in normal rats. This radiotracer was prepared using a commercial phytate cold kit after reconstitution with saline, (68) Ga-chloride generator eluent, calcium chloride, and air, then heating at 100°C for 30 minutes to achieve 99% radiochemical purity of (68) Ga-particles that were 21% 3-5 μm, 8% 5-15 μm, and 71% >15 μm in diameter. This optimal formulation was stable for 2 hours at room temperature. Intravenous administration of (68) Ga-particles in rats resulted in an uptake of 93% in the lungs, 4% in the liver plus spleen, and 3% in the carcass after 20 minutes. Two-thirds of the carcass activity was radioactive blood, likely to be (68) Ga-transferrin. The positron emission tomography image was superior than the (99m) Tc-MAA image because it displayed high lung uptake against a low background. Low uptake by the liver, spleen did not interfere with the diagnostic quality, and faint activity in the submandibular (salivary) glands was due to (68) Ga-transferrin. The preclinical data so far indicate that (68) Ga-Ca-phytate particles have good potential as a lung perfusion imaging agent.

  20. Formation and reaction of allylic species on silver surfaces: bond-order conservation Morse-potential analysis (United States)

    Shustorovich, Evgeny


    The reaction energetics, particularly the intrinsic activation barriers for possible reactions involving allylic species C 3H 5X, X = H, OH, O, Cl on clean and oxygen-preadsorbed Ag surfaces, have been calculated by using the bond-order conservation Morse-potential (BOC-MP) method. The calculations were made for low coverages of C 3H 5X with qualitative corrections for higher coverages. On clean Ag surfaces, propylene C 3H 6 and allyl alcohol C 3H 5OH are projected to desorb without dissociation, in contrast to allyl chloride C 3H 5C1, which is projected to desorb only at high coverages but to dissociate at low coverages forming a stable π-allyl (and atomic chlorine). It is found that the intrinsic activation barrier for dimerization of π-allyl into 1,5-hexadiene is very small and the apparent barrier should be mainly of diffusional character. In the presence of preadsorbed hydroxyl OH s, π-allyl is projected to undergo various transformations producing allyl alcohol, allyl alkoxide, acrolein, and propylene, when most recombination and disproportionation reactions have low intrinsic activation barriers. The BOC-MP model projections are in good agreement with experiment, particularly with the recent HREEL and TPD studies of C 3H 5C1.

  1. Appendix D: Use of wave scenarios to assess potential submerged oil mat (SOM) formation along the coast of Florida and Alabama (United States)

    Dalyander, P. Soupy; Long, Joseph W.; Plant, Nathaniel G.; Thompson, David M.


    During the Deepwater Horizon oil spill, oil in the surf zone mixed with sediment in the surf zone to form heavier-than-water sediment oil agglomerates of various size, ranging from small (cm-scale) pieces (surface residual balls, SRBs) to large mats (100-m scale, surface residue mats, SR mats). Once SR mats formed in the nearshore or in the intertidal zone, they may have become buried by sand moving onshore or alongshore. To assist in locating possible sites of buried oil, wave scenarios previously developed by the U.S. Geological Survey (USGS) were used to determine the depths at which surface oil had the potential to mix with suspended sediment. For sediment to mix with floating oil and form an agglomerate of sufficient density to sink to the seafloor, either the water must be very shallow (e.g., within the swash zone) or sediment must be suspended to the water surface in sufficient concentrations to create a denser-than-sea water agglomerate. The focus of this study is to analyze suspended sediment mixing with surface oil in depths beyond the swash zone, in order to define the seaward limit of mat formation. A theoretical investigation of sediment dynamics in the nearshore zone revealed that non-breaking waves do not suspend enough sediment to the surface to form sinking sand/oil agglomerates. For this study, it was assumed that the cross-shore distribution of potential agglomerate formation is associated with the primary breaker line, and the presence of plunging breakers, over the time frame of oiling. The potential locations of submerged oil mats (SOMs) are sites where (1) possible agglomerate formation occurred, where (2) sediment accreted post-oiling and buried the SOM, and where (3) the bathymetry has not subsequently eroded to re-expose any mat that may have formed at that site. To facilitate identification of these locations, the range of water level variation over the time frame of oiling was also prescribed, which combined with the wave-breaking depth

  2. Analysis of Tank 38H (HTF-38-14-150, 151) and Tank 43H (HTF- 43-14-152, 53) Surface and Subsurface Supernatant Samples in Support of Enrichment Control, Corrosion Control and Sodium Aluminosilicate Formation Potential Programs

    Energy Technology Data Exchange (ETDEWEB)

    Oji, L. N. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)


    This report provides the results of analyses on Tanks 38H and 43H surface and subsurface supernatant liquid samples in support of the Enrichment Control Program (ECP), the Corrosion Control Program and Sodium Aluminosilicate Formation Potential in the Evaporator.

  3. Effect of preozonation on the characteristic transformation of fulvic acid and its subsequent trichloromethane formation potential: presence or absence of bicarbonate. (United States)

    Li, Jing; Liu, Huijuan; Zhao, Xu; Qu, Jiuhui; Liu, Ruiping; Ru, Jia


    The effects of bicarbonate on the characteristic transformation of fulvic acid (FA) and its subsequent trichloromethane formation potential (TCMFP) were investigated in the process of preozonation. Dissolved organic carbon (DOC) removal rate and the residual aqueous ozone concentration during preozonation were measured with different bicarbonate concentration. The presence of bicarbonate inhibited DOC removal and decreased TCMFP yields in the initial oxidation period. In order to explain these phenomena, the molecular weight (MW) distribution (30 kDa) and corresponding TCMFP were investigated for FA and its subsequent oxidation products. Furthermore, transformation of molecular structure, based on MW distribution, was also characterized with Fourier transform infrared (FTIR) spectrum. Bicarbonate showed different inhibiting effects on TCMFP of organic species with different MW, and more significant TCMFP decrement was observed for the high MW fraction (>30 kDa) than for the low MW fractions. Preozonation led to obvious reduction on DOC and UV254 in most of MW fractions wherever bicarbonate was present or not, demonstrating that ozone contributed to both organics mineralization and structure variation, synchronously. As being indicated from the results of FTIR and gas chromatography-mass spectrometry, the functional groups such as alcohols, epoxides and phenols, the formation of which was promoted with hydroxyl radicals (.OH) and would be remarkably inhibited by bicarbonate, were responsible for the increment of TCM precursor's concentration during ozonation. Results of these studies confirmed low dosage bicarbonate affecting the ozonation pathways, influencing the intermediate species formation and impacting its subsequent TCMFP yields through inhibiting the .OH radicals reactions mainly occurred in high MW fractions.

  4. Overview of the PCDD/Fs degradation potential and formation risk in the application of advanced oxidation processes (AOPs) to wastewater treatment. (United States)

    Vallejo, Marta; Fresnedo San Román, M; Ortiz, Inmaculada; Irabien, Angel


    Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) are a family of unintentionally produced persistent organic pollutants (POPs) that have received considerable public and scientific attention due to the toxicity of some of their congeners, more specifically those with chlorine substitution in the 2,3,7,8 positions. The environmental management and control of PCDD/Fs is addressed at a global level through the Stockholm Convention that establishes that POPs should be destroyed or irreversibly transformed in order to reduce or eliminate their release to the environment. Several technologies, including advanced oxidation processes (AOPs) such as photolysis, photocatalysis and Fenton oxidation, have been considered as effective methods for destroying PCDD/Fs in polluted waters. Nevertheless, during the remediation of wastewaters it is critical that the treatment technologies applied do not lead to the formation of by-products that are themselves POPs, especially if PCDD/Fs precursors or chlorine are present in the reaction medium. Despite the high effectiveness of AOPs in the oxidation of major contaminants, scarce references deal with the monitoring of PCDD/Fs in the course of the oxidation process, revealing that a detailed assessment of non-combustion technologies with respect to PCDD/Fs formation is still lacking. This study reports a review of the state of the art related to the potential remediation and/or formation of PCDD/Fs as a result of the application of AOPs for the treatment of polluted waters, warning on the correct selection of the operating conditions.

  5. Endothelial transient receptor potential conical channel (TRPC)-3 activation induces vasogenic edema formation in the rat piriform cortex following status epilepticus. (United States)

    Ryu, Hea Jin; Kim, Ji-Eun; Kim, Yeon-Joo; Kim, Ji-Yang; Kim, Won I L; Choi, So-Yeon; Kim, Min-Ju; Kang, Tae-Cheon


    Transient receptor potential canonical channel (TRPC) is a nonselective cation channel permeable to Ca(2+), which express in many cell types, including neurons. However the alterations in TRPC receptor expressions in response to status epilepticus (SE) have not been explored. Therefore, the present study was designated to elucidate the roles of TRPC3 in neuronal death and vasogenic edema within the rat piriform cortex (PC) following SE. In non-SE animals, TRPC3 immunoreactivity was abundantly detected in the PC. Following SE, TRPC3 immunoreactivity was increased in neurons. Furthermore, TRPC3 expression was detected in endothelial cells that did not contain it in non-SE animals. Loss of SMI-71 (a blood-brain barrier antigen) immunoreactivity was also observed in TRPC3 positive endothelial cells. In addition, FJB positive neurons and vasogenic edema were noticeably detected in the PC. To directly determine whether TRPC3 activation is correlated to SE-induced vasogenic edema formation and neuronal damages in the PC, the effect of Pyr-3 (a TRPC3 antagonist) on SE-induced insults were investigated. Pyr-3 infusion effectively attenuated vasogenic edema in the PC as compared to the vehicle. Therefore, our findings indicate that TRPC3 activation/overexpression induced by SE may involve BBB disruption and neuronal damages in the rat PC following SE. Therefore, the present study was TRPC3 may play an important role in SE-induced vasogenic edema formation through BBB disruptions in the rat PC.

  6. Tracing dissolved organic carbon and trihalomethane formation potential between source water and finished drinking water at a lowland and an upland UK catchment. (United States)

    Brooks, Emma; Freeman, Christopher; Gough, Rachel; Holliman, Peter J


    Rising dissolved organic carbon (DOC) concentrations in many upland UK catchments represents a challenge for drinking water companies, in particular due to the role of DOC as a precursor in the formation of trihalomethanes (THMs). Whereas traditionally, the response of drinking water companies has been focussed on treatment processes, increasingly, efforts have been made to better understanding the role of land use and catchment processes in affecting drinking water quality. In this study, water quality, including DOC and THM formation potential (THMFP) was assessed between the water source and finished drinking water at an upland and a lowland catchment. Surprisingly, the lowland catchment showed much higher reservoir DOC concentrations apparently due to the influence of a fen within the catchment from where a major reservoir inflow stream originated. Seasonal variations in water quality were observed, driving changes in THMFP. However, the reservoirs in both catchments appeared to dampen these temporal fluctuations. Treatment process applied in the 2 catchments were adapted to reservoir water quality with much higher DOC and THMFP removal rates observed at the lowland water treatment works where coagulation-flocculation was applied. However, selectivity during this DOC removal stage also appeared to increase the proportion of brominated THMs produced. Copyright © 2015. Published by Elsevier B.V.

  7. Development of a ReaxFF potential for Pt-O systems describing the energetics and dynamics of Pt-oxide formation. (United States)

    Fantauzzi, Donato; Bandlow, Jochen; Sabo, Lehel; Mueller, Jonathan E; van Duin, Adri C T; Jacob, Timo


    ReaxFF force field parameters describing Pt-Pt and Pt-O interactions have been developed and tested. The Pt-Pt parameters are shown to accurately account for the chemical nature, atomic structures and other materials properties of bulk platinum phases, low and high-index platinum surfaces and nanoclusters. The Pt-O parameters reliably describe bulk platinum oxides, as well as oxygen adsorption and oxide formation on Pt(111) terraces and the {111} and {100} steps connecting them. Good agreement between the force field and both density functional theory (DFT) calculations and experimental observations is demonstrated in the relative surface free energies of high symmetry Pt-O surface phases as a function of the oxygen chemical potential, making ReaxFF an ideal tool for more detailed investigations of more complex Pt-O surface structures. Validation for its application to studies of the kinetics and dynamics of surface oxide formation in the context of either molecular dynamics (MD) or Monte Carlo simulations are provided in part by a two-part investigation of oxygen diffusion on Pt(111), in which nudged elastic band (NEB) calculations and MD simulations are used to characterize diffusion processes and to determine the relevant diffusion coefficients and barriers. Finally, the power of the ReaxFF reactive force field approach in addressing surface structures well beyond the reach of routine DFT calculations is exhibited in a brief proof-of-concept study of oxygen adsorbate displacement within ordered overlayers.

  8. Spatially resolved physical conditions of molecular gas and potential star formation tracers in M83, revealed by the Herschel SPIRE FTS

    CERN Document Server

    Wu, Ronin; Galliano, Frédéric; Wilson, Christine D; Kamenetzky, Julia; Lee, Min-Young; Schirm, Maximilien; Hony, Sacha; Lebouteiller, Vianney; Spinoglio, Luigi; Cormier, Diane; Glenn, Jason; Maloney, Philip R; Pereira-Santaella, Miguel; Rémy-Ruyer, Aurélie; Baes, Martin; Boselli, Alexandro; Bournaud, Frédéric; De Looze, Ilse; Hughes, Thomas M; Panuzzo, Pasquale; Rangwala, Naseem


    Since the launch of the Herschel Space Observatory, our understanding about the photo-dissociation regions (PDR) has taken a step forward. In the bandwidth of the Fourier Transform Spectrometer (FTS) of the Spectral and Photometric Imaging REceiver (SPIRE) on board Herschel, ten CO rotational transitions, including J=4-3 to J=13-12, and three fine structure lines, including [CI] 609, [CI] 370, and [NII] 250 micron, are covered. In this paper, I present our findings from the FTS observations at the nuclear region of M83, based on the spatially resolved physical parameters derived from the CO spectral line energy distribution (SLED) map and the comparisons with the dust properties and star-formation tracers. I will discuss (1) the potential of using [NII] 250 and [CI] 370 micron as star-formation tracers; (2) the reliability of tracing molecular gas with CO; (3) the excitation mechanisms of warm CO; (4) the possibility of studying stellar feedback by tracing the thermal pressure of molecular gas in the nuclear ...

  9. Assessing trihalomethanes (THMs) and N-nitrosodimethylamine (NDMA) formation potentials in drinking water treatment plants using fluorescence spectroscopy and parallel factor analysis. (United States)

    Yang, Liyang; Kim, Daekyun; Uzun, Habibullah; Karanfil, Tanju; Hur, Jin


    The formation of disinfection byproducts (DBPs) is a major challenge in drinking water treatments. This study explored the applicability of fluorescence excitation-emission matrices and parallel factor analysis (EEM-PARAFAC) for assessing the formation potentials (FPs) of trihalomethanes (THMs) and N-nitrosodimethylamine (NDMA), and the treatability of THM and NDMA precursors in nine drinking water treatment plants. Two humic-like and one tryptophan-like components were identified for the samples using PARAFAC. The total THM FP (TTHM FP) correlated strongly with humic-like component C2 (r=0.874), while NDMA FP showed a moderate and significant correlation with the tryptophan-like component C3 (r=0.628). The reduction by conventional treatment was more effective for C2 than C3, and for TTHM FP than NDMA FP. The treatability of DOM and TTHM FP correlated negatively with the absorption spectral slope (S275-295) and biological index (BIX) of the raw water, but it correlated positively with humification index (HIX). Our results demonstrated that PARAFAC components were valuable for assessing DBPs FP in drinking water treatments, and also that the raw water quality could affect the treatment efficiency.

  10. Investigation of the formation of benzoyl peroxide, benzoic anhydride, and other potential aerosol products from gas-phase reactions of benzoylperoxy radicals (United States)

    Strollo, Christen M.; Ziemann, Paul J.


    The secondary organic aerosol (SOA) products of the reaction of benzaldehyde with Cl atoms and with OH radicals in air in the absence of NOx were investigated in an environmental chamber in order to better understand the possible role of organic peroxy radical self-reactions in SOA formation. SOA products and authentic standards were analyzed using mass spectrometry and liquid chromatography, and results show that the yields of benzoyl peroxide (C6H5C(O)OO(O)CC6H5) and benzoic anhydride (C6H5C(O)O(O)CC6H5), two potential products from the gas-phase self-reaction of benzoylperoxy radicals (C6H5C(O)OO·), were less than 0.1%. This is in contrast to results of recent studies that have shown that the gas-phase self-reactions of β-nitrooxyperoxy radicals formed from reactions of isoprene with NO3 radicals form dialkyl peroxides that contribute significantly to gas-phase and SOA products. Such reactions have also been proposed to explain the gas-phase formation of extremely low volatility dimers from autooxidation of terpenes. The results obtained here indicate that, at least for benzoylperoxy radicals, the self-reactions form only benzoyloxy radicals. Analyses of SOA composition and volatility were inconclusive, but it appears that the SOA may consist primarily of oligomers formed through heterogeneous/multiphase reactions possibly involving some combination of phenol, benzaldehyde, benzoic acid, and peroxybenzoic acid.

  11. The impacts of low-cost treatment options upon scale formation potential in remote communities reliant on hard groundwaters. A case study: Northern Territory, Australia. (United States)

    Kinsela, Andrew S; Jones, Adele M; Collins, Richard N; Waite, T David


    The majority of small, remote communities within the Northern Territory (NT) in Central Australia are reliant on groundwater as their primary supply of domestic, potable water. Saturation indices for a variety of relevant minerals were calculated using available thermodynamic speciation codes on collected groundwater data across the NT. These saturation indices were used to assess the theoretical formation of problematic mineral-scale, which manifests itself by forming stubborn coatings on domestic appliances and fixtures. The results of this research show that 63% of the measured sites within the NT have the potential to form calcium carbonate (CaCO(3)) scale, increasing to 91% in arid, central regions. The data also suggests that all groundwaters are over-saturated with respect to amorphous calcium-bridged ferric-silica polymers, based on the crystalline mineral index (Ca(3)Fe(2)Si(3)O(12)), although the quantitative impact of this scale is limited by low iron concentrations. An assessment of possible low-cost/low-technology management options was made, including; lowering the temperature of hot-water systems, diluting groundwater with rainwater and modifying the pH of the source water. Source water pH modification (generally a reduction to pH 7.0) was shown to clearly alleviate potential carbonate-based scale formation, over and above the other two options, albeit at a greater technical and capital expense. Although low-cost/low-technology treatment options are unlikely to remove severe scale-related issues, their place in small, remote communities with minor scale problems should be investigated further, owing to the social, technical and capital barriers involved with installing advanced treatment plants (e.g. reverse osmosis) in such locations.

  12. Characterizing the chemical evolution of air masses via multi-platform measurements of volatile organic compounds (VOCs) during CalNEX: Composition, OH reactivity, and potential SOA formation (United States)

    Gilman, J. B.; Kuster, W. C.; Bon, D.; Warneke, C.; Lerner, B. M.; Williams, E. J.; Holloway, J. S.; Pollack, I. B.; Ryerson, T. B.; Atlas, E. L.; Blake, D. R.; Herndon, S. C.; Zahniser, M. S.; Vlasenko, A. L.; Li, S.; Alvarez, S. L.; Rappenglueck, B.; Flynn, J. H.; Grossberg, N.; Lefer, B. L.; De Gouw, J. A.


    Volatile organic compounds (VOCs) are critical components in the photochemical production of ozone (O3) and secondary organic aerosol (SOA). During the CalNex 2010 field campaign, an extensive set of VOCs were measured at the Pasadena ground site, and aboard the NOAA WP-3D aircraft and the WHOI Research Vessel Atlantis. The measurements from each platform provide a unique perspective into the emissions, transport, and atmospheric processing of VOCs within the South Coast Air Basin (SoCAB). The observed enhancement ratios of the hydrocarbons measured on all three platforms are in good agreement and are generally well correlated with carbon monoxide (CO), indicating the prevalence of on-road VOC emission sources throughout the SoCAB. Offshore measurements aboard the ship and aircraft are used to characterize the air mass composition as a function of the land/sea-breeze effect. VOC ratios and other trace gases are used to identify air masses containing relatively fresh emissions that were often associated with offshore flow and re-circulated continental air associated with onshore flow conditions. With the prevailing southwesterly airflow pattern in the LAB throughout the daytime, the Pasadena ground site effectively functions as a receptor site and is used to characterize primary VOC emissions from downtown Los Angeles and to identify the corresponding secondary oxidation products. The chemical evolution of air masses as a function of the time of day is investigated in order to determine the relative impacts of primary emissions vs. secondary VOC products on OH reactivity and potential SOA formation. The reactivity of VOCs with the hydroxyl radical (OH) at the Pasadena site was dominated by the light hydrocarbons, isoprene, and oxygenated VOCs including aldehydes (secondary products) and alcohols (primary anthropogenic emissions). Toluene and benzaldehyde, both of which are associated with primary anthropogenic emissions, are the predominant VOC precursors to the

  13. Formation and stability of manganese-doped ZnS quantum dot monolayers determined by QCM-D and streaming potential measurements. (United States)

    Oćwieja, Magdalena; Matras-Postołek, Katarzyna; Maciejewska-Prończuk, Julia; Morga, Maria; Adamczyk, Zbigniew; Sovinska, Svitlana; Żaba, Adam; Gajewska, Marta; Król, Tomasz; Cupiał, Klaudia; Bredol, Michael


    Manganese-doped ZnS quantum dots (QDs) stabilized by cysteamine hydrochloride were successfully synthesized. Their thorough physicochemical characteristics were acquired using UV-Vis absorption and photoluminescence spectroscopy, X-ray diffraction, dynamic light scattering (DLS), transmission electron microscopy (HR-TEM), energy dispersive spectroscopy (EDS) and Fourier transform infrared (FT-IR) spectroscopy. The average particle size, derived from HR-TEM, was 3.1nm, which agrees with the hydrodynamic diameter acquired by DLS, that was equal to 3-4nm, depending on ionic strength. The quantum dots also exhibited a large positive zeta potential varying between 75 and 36mV for ionic strength of 10(-4) and 10(-2)M, respectively (at pH 6.2) and an intense luminescent emission at 590nm. The quantum yield was equal to 31% and the optical band gap energy was equal to 4.26eV. The kinetics of QD monolayer formation on silica substrates (silica sensors and oxidized silicon wafers) under convection-controlled transport was quantitatively evaluated by the quartz crystal microbalance (QCM) and the streaming potential measurements. A high stability of the monolayer for ionic strength 10(-4) and 10(-2)M was confirmed in these measurements. The experimental data were adequately reflected by the extended random sequential adsorption model (eRSA). Additionally, thorough electrokinetic characteristics of the QD monolayers and their stability for various ionic strengths and pH were acquired by streaming potential measurements carried out under in situ conditions. These results were quantitatively interpreted in terms of the three-dimensional (3D) electrokinetic model that furnished bulk zeta potential of particles for high ionic strengths that is impractical by other experimental techniques. It is concluded that these results can be used for designing of biosensors of controlled monolayer structure capable to bind various ligands via covalent as well as electrostatic interactions

  14. Effect of varying feedstock-pretreatment chemistry combinations on the formation and accumulation of potentially inhibitory degradation products in biomass hydrolysates. (United States)

    Du, Bowen; Sharma, Lekh N; Becker, Christopher; Chen, Shou-Feng; Mowery, Richard A; van Walsum, G Peter; Chambliss, C Kevin


    A variety of potentially inhibitory degradation products are produced during pretreatment of lignocellulosic biomass. Qualitative and quantitative interrogation of pretreatment hydrolysates is paramount to identifying potential correlations between pretreatment chemistries and microbial inhibition in downstream bioconversion processes. In the present study, corn stover, poplar, and pine feedstocks were pretreated under eight different chemical conditions, which are representative of leading pretreatment processes. Pretreatment processes included: 0.7% H(2)SO(4), 0.07% H(2)SO(4), liquid hot water, neutral buffer solution, aqueous ammonia, lime, lime with oxygen pressurization, and wet oxidation. Forty lignocellulosic degradation products resulting from pretreatment were analyzed using high performance liquid chromatography in combination with UV spectroscopy or tandem mass spectrometry detection (HPLC-PDA-MS/MS) and ion chromatography (IC). Of these compounds, several have been reported to be inhibitory, including furfural, hydroxymethyl furfural, ferulic acid, 3,4-dihydroxybenzaldehyde, syringic acid among others. Formation and accumulation of monitored compounds in hydrolysates is demonstrated to be a function of both the feedstock and pretreatment conditions utilized.

  15. Hydrocarbon potential of Early Cretaceous lacustrine sediments from Bima Formation, Yola Sub-basin, Northern Benue Trough, NE Nigeria: Insight from organic geochemistry and petrology (United States)

    Sarki Yandoka, Babangida M.; Abdullah, Wan Hasiah; Abubakar, M. B.; Adegoke, Adebanji Kayode; Maigari, A. S.; Haruna, A. I.; Yaro, Usman Y.


    The Early Cretaceous lacustrine sediments from Bima Formation in the Yola Sub-basin, Northern Benue Trough, northeastern Nigeria were studied based on organic geochemistry and petrology. This is in other to provide information on hydrocarbon generation potential; organic matter type (quality), richness (quantity), origin/source inputs, redox conditions (preservation) and thermal maturation in relation to thermal effect of Tertiary volcanics. The total organic carbon (TOC) contents ranges from 0.38 to 0.86 wt % with extractable organic matter (EOM) below 1000 ppm and pyrolysis S2 yield values from 0.16 to 0.68 mg/g, suggesting poor to fair source rock richness. Based on kerogen pyrolysis and microscopy coupled with biomarker parameters, the organic matters contain Type I (lacustrine algae), Type III (terrestrially derived land-plants) and Type IV kerogens deposited in a mixed lacustrine-terrestrial environment under suboxic to relatively anoxic conditions. This suggest potential occurrence of Early Cretaceous lacustrine sediments (perhaps Lower Cretaceous petroleum system) in Yola Sub-basin of the Northern Benue Trough as present in the neighbouring basins of Chad, Niger and Sudan Republics that have both oil and gas generation potential within the same rift trend (WCARS). Vitrinite reflectance (%Ro) and Tmax values of the lacustrine shales ranges from 1.12 to 2.32 VRo% and 448-501 °C, respectively, indicating peak-late to post-maturity stage. This is supported by the presence of dark brown palynomorphs, amorphous organic matter and phytoclasts as well as inertinite macerals. Consequently, the organic matters in the lacustrine shales of Bima Formation in the Yola Sub-basin appeared as a source of oil (most likely even waxy) and gas prone at a relatively deeper part of the basin. However, the high thermal maturity enhanced the organic matters and most of the hydrocarbons that formed in the course of thermal maturation were likely expelled to the reservoir rock units

  16. The Necessity and Basic Directions of Improving the Procedure for the Formation and Use of the Resource Potential of Health Care in Ukraine

    Directory of Open Access Journals (Sweden)

    Dolbneva Deniza V.


    Full Text Available The aim of the article is to determine the status and main problems of the resource provision of Ukraine’s health care system and identify the most appropriate and relevant directions of improving the procedure for its formation and use in the context of the current social and economic transformations. The study considers indicators characterizing the status of funding expenditures on the functioning of the health system for the past 4 years, the plan for the current year and the forecast for the following one. This made it possible to make a conclusion about the budget model and residual principle of funding the branch; the insufficient amount of expenditures on health care; the inefficiency, illegality and irrationality of their implementation by the existing network of health care institutions; the low level of the state and regional control over the resource potential of Ukraine’s health care system. To overcome these negative trends and ensure the health system reform in accordance with the Strategy for Sustainable Development “Ukraine – 2020”, there considered a mechanism of state control over resources provision of the health care system, the implementation of which will improve the quality of health of the population, provide full access to health services, increase the level of funding and efficiency of using the resource potential of the health care system. There also proposed a number of measures which, in the authors’ opinion, will create sufficient conditions for improving the procedure of forming and using the branch resource potential.Prospects for further research are developing a mechanism for attracting additional sources to the branch funding, studying and adapting experience of leading countries of the world in reforming the health system, improving the classification of financial resources of health care institutions.

  17. Effects of Ca(OH)2 assisted aluminum sulfate coagulation on the removal of humic acid and the formation potentials of tri-halomethanes and haloacetic acids in chlorination

    Institute of Scientific and Technical Information of China (English)

    Jinming Duan; Xiaoting Cao; Cheng Chen; Dongrui Shi; Genmao Li; Dennis Mulcahy


    The effects of addition of calcium hydroxide on aluminum sulphate (or alum) coagulation for removal of natural organic matter (NOM) and its subsequent effect on the formation potentials of two major types of regulated disinfection byproducts (DBPs),haloacetic acids (HAAs) and trihalomethanes (THMs),have been examined.The results revealed several noteworthy phenomena.At the optimal coagulation pH (i.e.6),the coagulation behavior of NOM water solutions versus alum dose,showed large variation and a consequent great change in the formation potentials of the DBPs at certain coagulant doses.However,with addition of a relatively small amount of Ca(OH)2,although the zeta potential of coagulated flocs remained almost the same,NOM removal became more consistent with alum dose.Importantly,also the detrimental effect of charge reversal on NOM removal at the low coagulant dose disappeared.This resulted in a steady decrease in the formation potentials of DBPs as a function of the coagulant dose.Moreover,the addition of Ca(OH)2 broadened the pH range of alum coagulation and promoted further reduction of the formation potentials of the DBPs.The enhancement effects of Ca(OH)2 assisted alum coagulation are especially pronounced at pH 7 and 8.Finally,synchronous fluorescence spectra showed that the reduction in DBPs formation potential by Ca(OH)2-assisted alum coagulation was connected to an enhanced removal of small hydrophobic and hydrophilic HA molecules.Ca(OH)2-assistance of alum coagulation appeared to increase substantially the removal of the hydrophilic HA fraction responsible for HAAs formation,prompting further reduction of HAA formation potentials.

  18. Organic geochemical characteristics of the Lower Cretaceous Abu Gabra Formation in the Great Moga oilfield, Muglad Basin, Sudan: Implications for depositional environment and oil-generation potential (United States)

    Makeen, Yousif M.; Abdullah, Wan Hasiah; Hakimi, Mohammed Hail; Elhassan, Osman M. A.


    Organic-rich sediments within the Abu Gabra Formation from three wells in the Great Moga oilfield were analyzed using organic geochemistry and organic petrology. The analyzed samples generally contain more than 2.0 wt.% TOC and have a very good to excellent hydrocarbon generative potential. This is supported by high bitumen extract and hydrocarbon (HCs) yields with values exceeding 4000 and 2000 ppm, respectively. The Abu Gabra also have moderate to high hydrogen index (HI) values of 287-865 mg HC/g TOC and large amounts of amorphous organic matter and alginite, consistent with oil-prone Types I and Type II kerogen. Vitrinite reflectance (0.59-0.72) %Ro and pyrolysis Tmax (430-438 °C) indicate an early oil window stage. This is supported by bitumen/TOC ratios (0.04-0.09) and biomarker thermal maturity parameters with equilibrium C32 homohopane 22S/(22S + 22R) ratios (0.50-58), moretane/hopane (0.11-018) and C29ββ/(ββ + αα) (0.53-0.73) and 20S/(20S + 20R) ratios (0.26-0.48). The biomarkers are characterized by a dominance of low to medium molecular weight n-alkane compounds with significant waxy alkanes (n-C25-n-C34), moderately high Pr/Ph ratios (1.17-2.51), high abundance of C27 regular steranes, high C27/C29 regular sterane ratios, the presence of tricyclic terpanes and relatively low sterane/hopane ratios. These data indicate that the organic-rich sediments of the Abu Gabra Formation contain a mixture of aquatic (algal and bacterial) and terrigenous organic matter, deposited in a lacustrine environment and preserved under suboxic conditions.

  19. Concentration, composition, bioavailability, and N-nitrosodimethylamine formation potential of particulate and dissolved organic nitrogen in wastewater effluents: A comparative study. (United States)

    Hu, Haidong; Ma, Haijun; Ding, Lili; Geng, Jinju; Xu, Ke; Huang, Hui; Zhang, Yingying; Ren, Hongqiang


    Wastewater-derived organic nitrogen (org-N) can act as both nutrients and carcinogenic nitrogenous disinfection byproduct precursors. In this study, the concentration, composition, bioavailability, and N-nitrosodimethylamine (NDMA) formation potential of particulate organic nitrogen (PON) from three different municipal wastewater treatment plants were characterized and compared with that of effluent dissolved organic nitrogen (DON). The average effluent PON and DON concentrations ranged from 0.09 to 0.55mgN/L and from 0.91 to 1.88mgN/L, respectively. According to principal component analysis, org-N composition and characterization differed in PON and DON samples (n=20). Compared with DON, PON tended to be enriched in protein and nucleic acids, and showed a more proteinaceous character. Composition of org-N functional groups estimated from the X-ray photoelectron spectroscopy N 1s spectra indicate no significant differences in the molecular weight distribution of the protein-like materials between PON and DON. Moreover, PON exhibited a significantly higher bioavailability (61.0±13.3%) compared to DON (38.5±12.4%, p˂0.05, t-test) and a significantly higher NDMA yields (791.4±404.0ng/mg-N) compared to DON (374.8±62.5ng/mg-N, p˂0.05, t-test). Accordingly, PON contributed to approximately 12.3-41.7% of the total bioavailable org-N and 22.0-38.4% of the total NDMA precursors in wastewater effluents. Thus, the potential adverse effects of PON on wastewater discharge and reuse applications should not be overlooked, even though it only accounted for 7.4-26.8% of the total effluent org-N.

  20. The role of small and medium-sized high-tech enterprise in the formation of innovative potential of the Voronezh region

    Directory of Open Access Journals (Sweden)

    E. A. Shubina


    Full Text Available In modern conditions the region's sustainable development and economic growth is largely determined by its ability to implement innovations. One of the determining factors of long-term economic development of the territories, to date, is innovation. A mechanism to give impetus to the innovative development of the regions is to create effective small and medium-sized innovative enterprises. Voronezh region, like many Russian regions, has considerable potential for innovation, but usually it is not used efficiently or not used at all. The article deals with the concept and the need to develop innovative entrepreneurship and the role of small and medium innovative enterprises in the formation of scientific and technical potential of the Voronezh region. The basic conditions and factors promoting and impeding the development of small and medium innovative businesses in the region, determined the willingness of subjects of innovation activity in the development, implementation and promotion of innovation in the region. The problems of development of small and medium-sized businesses at the regional level. The evaluation of actions to improve SMEs management programs in the region. Particular attention is given to the classification of small and medium-sized innovative business structures. In order to stimulate the development of small and medium-sized innovative business in the Voronezh region in the article suggests the implementation of a package of measures. The active use of innovation by small and medium-sized enterprises of the Voronezh area enhances their efficiency and competitiveness, creates new jobs, which ultimately has a positive effect on the region's economic development, the growth of the tax base, improving the quality of life of the population.

  1. Role of Tertiary Lymphoid Structures (TLS) in Anti-Tumor Immunity: Potential Tumor-Induced Cytokines/Chemokines that Regulate TLS Formation in Epithelial-Derived Cancers

    Energy Technology Data Exchange (ETDEWEB)

    Pimenta, Erica M. [Rutgers Biomedical and Health Sciences, New Jersey Medical School-Cancer Center, Newark, NJ 07103 (United States); Barnes, Betsy J., E-mail: [Department of Biochemistry and Molecular Biology, Rutgers Biomedical and Health Sciences, New Jersey Medical School-Cancer Center, Newark, NJ 07103 (United States)


    Following the successes of monoclonal antibody immunotherapies (trastuzumab (Herceptin{sup ®}) and rituximab (Rituxan{sup ®})) and the first approved cancer vaccine, Provenge{sup ®} (sipuleucel-T), investigations into the immune system and how it can be modified by a tumor has become an exciting and promising new field of cancer research. Dozens of clinical trials for new antibodies, cancer and adjuvant vaccines, and autologous T and dendritic cell transfers are ongoing in hopes of identifying ways to re-awaken the immune system and force an anti-tumor response. To date, however, few consistent, reproducible, or clinically-relevant effects have been shown using vaccine or autologous cell transfers due in part to the fact that the immunosuppressive mechanisms of the tumor have not been overcome. Much of the research focus has been on re-activating or priming cytotoxic T cells to recognize tumor, in some cases completely disregarding the potential roles that B cells play in immune surveillance or how a solid tumor should be treated to maximize immunogenicity. Here, we will summarize what is currently known about the induction or evasion of humoral immunity via tumor-induced cytokine/chemokine expression and how formation of tertiary lymphoid structures (TLS) within the tumor microenvironment may be used to enhance immunotherapy response.

  2. Role of Tertiary Lymphoid Structures (TLS in Anti-Tumor Immunity: Potential Tumor-Induced Cytokines/Chemokines that Regulate TLS Formation in Epithelial-Derived Cancers

    Directory of Open Access Journals (Sweden)

    Erica M. Pimenta


    Full Text Available Following the successes of monoclonal antibody immunotherapies (trastuzumab (Herceptin® and rituximab (Rituxan® and the first approved cancer vaccine, Provenge® (sipuleucel-T, investigations into the immune system and how it can be modified by a tumor has become an exciting and promising new field of cancer research. Dozens of clinical trials for new antibodies, cancer and adjuvant vaccines, and autologous T and dendritic cell transfers are ongoing in hopes of identifying ways to re-awaken the immune system and force an anti-tumor response. To date, however, few consistent, reproducible, or clinically-relevant effects have been shown using vaccine or autologous cell transfers due in part to the fact that the immunosuppressive mechanisms of the tumor have not been overcome. Much of the research focus has been on re-activating or priming cytotoxic T cells to recognize tumor, in some cases completely disregarding the potential roles that B cells play in immune surveillance or how a solid tumor should be treated to maximize immunogenicity. Here, we will summarize what is currently known about the induction or evasion of humoral immunity via tumor-induced cytokine/chemokine expression and how formation of tertiary lymphoid structures (TLS within the tumor microenvironment may be used to enhance immunotherapy response.

  3. Performance of the widely used Minnesota density functionals for the prediction of heat of formations, ionization potentials of some benchmarked first row transition metal complexes. (United States)

    Shil, Suranjan; Bhattacharya, Debojit; Sarkar, Sonali; Misra, Anirban


    We have computed and investigated the performance of Minnesota density functionals especially the M05, M06, and M08 suite of complementary density functionals for the prediction of the heat of formations (HOFs) and the ionization potentials (IPs) of various benchmark complexes containing nine different first row transition metals. The eight functionals of M0X family, namely, the M05, M05-2X, M06-L, M06, M06-2X, M06-HF, M08-SO, and M08-HX are taken for the computation of the above-mentioned physical properties of such metal complexes along with popular Los Alamos National Laboratory 2 double-ζ (LANL2DZ) basis set. Total 54 benchmark systems are taken for HOF calculation, whereas the 47 systems among these benchmark complexes are chosen for the calculation of IPs because of lack of experimental results on rest of the seven systems. The computed values of HOFs and IPs are compared with the experimental results obtained from the literature. The deviation of these computed values from the actual experimental results is calculated for each eight different M0X functionals to judge their performances in evaluating these properties. Finally, a clear relationship between the exchange correlation energy of eight M0X functionals and their efficiency are made to predict the different physical properties.

  4. Trophic state, natural organic matter content, and disinfection by-product formation potential of six drinking water reservoirs in the Pearl River Delta, China (United States)

    Hong, Hua Chang; Wong, Ming Hung; Mazumder, Asit; Liang, Yan


    SummaryThis study examined spatial and seasonal variation of nutrients, algal biomass, and natural organic matter (NOM) in six subtropical drinking water reservoirs in the Pearl River Delta region, China, during the period from 2004 to 2006. We also tested the formation of trihalomethanes (THMs) and haloacetic acids (HAAs) as disinfection by-products (DBPs) via chlorination of the water samples from these reservoirs. This study showed that these reservoirs were mesotrophic with the average chlorophyll a (Chl a) levels ranging from 2.31 to 7.79 μg l -1. The average dissolved organic carbon (DOC) in the six reservoirs was 2.70 mg l -1, and the degree of aromaticity of NOM indicated by UV 254 (absorbance at 254 nm) was 0.048 cm -1. Total phosphorous (TP) was significantly correlated with chlorophyll a, as well as DOC and UV 254. It suggested that the major component of NOM, with a specific UV 254 value (SUV 254) of 1.78 l mg -1 m -1, was algal-derived organic matter. Existing models from other studies could be used to predict THM yield from NOM level in the present study, but the relationship between HAAs and NOM suggested that aromatic portion of the NOM in the investigated reservoirs had a greater potential to produce HAAs.

  5. Modeling organic aerosols in a megacity: potential contribution of semi-volatile and intermediate volatility primary organic compounds to secondary organic aerosol formation

    Directory of Open Access Journals (Sweden)

    A. Hodzic


    Full Text Available It has been established that observed local and regional levels of secondary organic aerosols (SOA in polluted areas cannot be explained by the oxidation and partitioning of anthropogenic and biogenic VOC precursors, at least using current mechanisms and parameterizations. In this study, the 3-D regional air quality model CHIMERE is applied to estimate the potential contribution to SOA formation of recently identified semi-volatile and intermediate volatility organic precursors (S/IVOC in and around Mexico City for the MILAGRO field experiment during March 2006. The model has been updated to include explicitly the volatility distribution of primary organic aerosols (POA, their gas-particle partitioning and the gas-phase oxidation of the vapors. Two recently proposed parameterizations, those of Robinson et al. (2007 ("ROB" and Grieshop et al. (2009 ("GRI" are compared and evaluated against surface and aircraft measurements. The 3-D model results are assessed by comparing with the concentrations of OA components from Positive Matrix Factorization of Aerosol Mass Spectrometer (AMS data, and for the first time also with oxygen-to-carbon ratios derived from high-resolution AMS measurements. The results show a substantial enhancement in predicted SOA concentrations (2–4 times with respect to the previously published base case without S/IVOCs (Hodzic et al., 2009, both within and downwind of the city leading to much reduced discrepancies with the total OA measurements. Model improvements in OA predictions are associated with the better-captured SOA magnitude and diurnal variability. The predicted production from anthropogenic and biomass burning S/IVOC represents 40–60% of the total measured SOA at the surface during the day and is somewhat larger than that from commonly measured aromatic VOCs, especially at the T1 site at the edge of the city. The SOA production from the continued multi-generation S/IVOC oxidation products continues actively

  6. Concentration, ozone formation potential and source analysis of volatile organic compounds (VOCs) in a thermal power station centralized area: A study in Shuozhou, China. (United States)

    Yan, Yulong; Peng, Lin; Li, Rumei; Li, Yinghui; Li, Lijuan; Bai, Huiling


    Volatile organic compounds (VOCs) from two sampling sites (HB and XB) in a power station centralized area, in Shuozhou city, China, were sampled by stainless steel canisters and measured by gas chromatography-mass selective detection/flame ionization detection (GC-MSD/FID) in the spring and autumn of 2014. The concentration of VOCs was higher in the autumn (HB, 96.87 μg/m(3); XB, 58.94 μg/m(3)) than in the spring (HB, 41.49 μg/m(3); XB, 43.46 μg/m(3)), as lower wind speed in the autumn could lead to pollutant accumulation, especially at HB, which is a new urban area surrounded by residential areas and a transportation hub. Alkanes were the dominant group at both HB and XB in both sampling periods, but the contribution of aromatic pollutants at HB in the autumn was much higher than that of the other alkanes (11.16-19.55%). Compared to other cities, BTEX pollution in Shuozhou was among the lowest levels in the world. Because of the high levels of aromatic pollutants, the ozone formation potential increased significantly at HB in the autumn. Using the ratio analyses to identify the age of the air masses and analyze the sources, the results showed that the atmospheric VOCs at XB were strongly influenced by the remote sources of coal combustion, while at HB in the spring and autumn were affected by the remote sources of coal combustion and local sources of vehicle emission, respectively. Source analysis conducted using the Positive Matrix Factorization (PMF) model at Shuozhou showed that coal combustion and vehicle emissions made the two largest contributions (29.98% and 21.25%, respectively) to atmospheric VOCs. With further economic restructuring, the influence of vehicle emissions on the air quality should become more significant, indicating that controlling vehicle emissions is key to reducing the air pollution.

  7. Antrodia camphorata Potentiates Neuroprotection against Cerebral Ischemia in Rats via Downregulation of iNOS/HO-1/Bax and Activated Caspase-3 and Inhibition of Hydroxyl Radical Formation

    Directory of Open Access Journals (Sweden)

    Po-Sheng Yang


    Full Text Available Antrodia camphorata (A. camphorata is a fungus generally used in Chinese folk medicine for treatment of viral hepatitis and cancer. Our previous study found A. camphorata has neuroprotective properties and could reduce stroke injury in cerebral ischemia animal models. In this study, we sought to investigate the molecular mechanisms of neuroprotective effects of A. camphorata in middle cerebral artery occlusion (MCAO rats. A selective occlusion of the middle cerebral artery (MCA with whole blood clots was used to induce ischemic stroke in rats and they were orally treated with A. camphorata (0.25 and 0.75 g/kg/day alone or combined with aspirin (5 mg/kg/day. To provide insight into the functions of A. camphorata mediated neuroprotection, the expression of Bax, inducible nitric oxide synthase (iNOS, haem oxygenase-1 (HO-1, and activated caspase-3 was determined by Western blot assay. Treatment of aspirin alone significantly reduced the expressions of HO-1 (P<0.001, iNOS (P<0.001, and Bax (P<0.01 in ischemic regions. The reduction of these expressions was more potentiated when rats treated by aspirin combined with A. camphorata (0.75 g/kg/day. Combination treatment also reduced apoptosis as measured by a significant reduction in active caspase-3 expression in the ischemic brain compared to MCAO group (P<0.01. Moreover, treatment of A. camphorata significantly (P<0.05 reduced fenton reaction-induced hydroxyl radical (OH• formation at a dose of 40 mg/mL. Taken together, A. camphorata has shown neuroprotective effects in embolic rats, and the molecular mechanisms may correlate with the downregulation of Bax, iNOS, HO-1, and activated caspase-3 and the inhibition of OH• signals.

  8. Lattice potential energy and standard molar enthalpy in the formation of 1-dodecylamine hydrobromide(1-C12H25NH3·Br)(s)

    Institute of Scientific and Technical Information of China (English)

    Liu Yu-Pu; Di You-Ying; Dan Wen-Yan; He Dong-Hua; Kong Yu-Xia; Yang Wei-Wei


    This paper reports that 1-dodecylamine hydrobromide (1-C12H25NH3·Br)(s) has been synthesized using the liquid phase reaction method. The lattice potential energy of the compound 1-C12H25NH3·Br and the ionic volume and radius of the 1-C12H25NH3+ cation are obtained from the crystallographic data and other auxiliary ther-modynamic data. The constant-volume energy of combustion of 1-C12H25NH3·Br(s) is measured to be △cUm°(1-C12H25NH3·Br, s) =-(7369.03±3.28) kJ·mol-1 by means of an RBC-Ⅱ precision rotating-bomb combustion calorimeter at T=(298.15±0.001) K. The standard molar enthalpy of combustion of the compound is derived to be △cHm°(1-C12H25NH3·Br, s)=-(7384.52±3.28) kJ·mol-1 from the constant-volume energy of combustion. The standard molar enthalpy of formation of the compound is calculated to be △fHm°(1-C12H25NH3·Br, s)=-(1317.86±3.67) kJ·mol-1 from the standard molar enthalpy of combustion of the title compound and other auxiliary thermodynamic quantities through a thermochemical cycle.

  9. High-potential perfluorinated phthalocyanine-fullerene dyads for generation of high-energy charge-separated states: formation and photoinduced electron-transfer studies. (United States)

    Das, Sushanta K; Mahler, Andrew; Wilson, Angela K; D'Souza, Francis


    High oxidation potential perfluorinated zinc phthalocyanines (ZnF(n)Pcs) are synthesised and their spectroscopic, redox, and light-induced electron-transfer properties investigated systematically by forming donor-acceptor dyads through metal-ligand axial coordination of fullerene (C60) derivatives. Absorption and fluorescence spectral studies reveal efficient binding of the pyridine- (Py) and phenylimidazole-functionalised fullerene (C60Im) derivatives to the zinc centre of the F(n)Pcs. The determined binding constants, K, in o-dichlorobenzene for the 1:1 complexes are in the order of 10(4) to 10(5) M(-1); nearly an order of magnitude higher than that observed for the dyad formed from zinc phthalocyanine (ZnPc) lacking fluorine substituents. The geometry and electronic structure of the dyads are determined by using the B3LYP/6-31G* method. The HOMO and LUMO levels are located on the Pc and C60 entities, respectively; this suggests the formation of ZnF(n)Pc(.+)-C60Im(.-) and ZnF(n)Pc(.+)-C60Py(.-) (n=0, 8 or 16) intra-supramolecular charge-separated states during electron transfer. Electrochemical studies on the ZnPc-C60 dyads enable accurate determination of their oxidation and reduction potentials and the energy of the charge-separated states. The energy of the charge-separated state for dyads composed of ZnF(n)Pc is higher than that of normal ZnPc-C60 dyads and reveals their significance in harvesting higher amounts of light energy. Evidence for charge separation in the dyads is secured from femtosecond transient absorption studies in nonpolar toluene. Kinetic evaluation of the cation and anion radical ion peaks reveals ultrafast charge separation and charge recombination in dyads composed of perfluorinated phthalocyanine and fullerene; this implies their significance in solar-energy harvesting and optoelectronic device building applications. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Formation flying as an innovative air transportation system for long-haul commercial flight: A focus on operational feasibility and potential gain

    NARCIS (Netherlands)

    Herinckx, L.E.; Gutleb, T.L.M.; Van Nunen, R.; Van Rompuy, E.; Bos, D.A.; Dijkers, H.P.A.; De Wit, J.; Radfar, H.; Sahin, S.E.; Beelarts van Blokland, W.W.A.


    Formation flying is introduced as a new and innovative air transportation system for long-haul commercial flight. With this paper the operational feasibility of formation flying is addressed, both from a market demand and economic, as well as an air traffic control perspective. Preliminary results o

  11. Long-term aerosol and trace gas measurements in Eastern Lapland, Finland: the impact of Kola air pollution to new particle formation and potential CCN (United States)

    Kyrö, Ella-Maria; Väänänen, Riikka; Kerminen, Veli-Matti; Virkkula, Aki; Asmi, Ari; Nieminen, Tuomo; Dal Maso, Miikka; Petäjä, Tuukka; Keronen, Petri; Aalto, Pasi; Riipinen, Ilona; Lehtipalo, Katrianne; Hari, Pertti; Kulmala, Markku


    Sulphur and primary emissions have been decreasing largely all over Europe, resulting in improved air quality and decreased direct radiation forcing by aerosols. The smelter industry in Kola Peninsula is one of largest sources of anthropogenic SO2 within the Arctic domain and since late 1990s the sulphur emissions have been decreasing rapidly (Paatero et al., 2008; Prank et al., 2010). New particle formation (NPF) is tightly linked with the oxidizing product of SO2, namely sulphuric acid (H2SO4), since it is known to be the key component in atmospheric nucleation (Sipilä et al., 2010). Thus, decreasing sulphur pollution may lead to less NPF. However, low values of condensation sink (CS), which is determined by the amount of pre-existing particles, favours NPF. We used 14 years (1998-2011) of aerosol number size distribution and trace gas data from SMEAR I station in Eastern Lapland, Finland, to investigate these relationships between SO2, NPF and CS. The station is a clean background station with occasional sulphur pollution episodes when the air masses arrive over Kola Peninsula. We found that while SO2 decreased by 11.3 % / year, the number of clear NPF event days was also decreasing by 9.9 % / year. At the same time, CS was decreasing also (-8.0 % / year) leading to formation of more particles per single NPF event (J3 increased by 29.7 % / year in 2006-2011) but the low vapour concentrations of H2SO4 (proxy decreased by 6.2 % / year) did not allow them to grow into climatically relevant sizes. Over the time, concentrations of potential CCN (cloud condensing nuclei) were also decreasing with more moderate pace, -4.0 % / year. The events started on average earlier after sunrise when the SO2 concentration during the start of the event was higher and NPF occurred more frequently in air masses which were travelling over Kola. Despite the total decrease in sulphur pollution originating from Kola there is currently no evidence of cleaning of the emissions, rather the

  12. Epitope reactions can be gauged by relative antibody discriminating specificity (RADS values supported by deletion, substitution and cysteine bridge formation analyses: potential uses in pathogenesis studies

    Directory of Open Access Journals (Sweden)

    Falconar Andrew K I


    Full Text Available Abstract Background Epitope-mapping of infectious agents is essential for pathogenesis studies. Since polyclonal antibodies (PAbs and monoclonal antibodies (MAbs are always polyspecific and can react with multiple epitopes, it is important to distinguish between specific and non-specific reactions. Relative antibody discriminating specificity (RADS values, obtained from their relative ELISA reactions with L-amino acid peptides prepared in the natural versus reverse orientations (x-fold absorbance natural/absorbance reverse = RADS value may be valuable for this purpose. PAbs generated against the dengue type-2 virus (DENV-2 nonstructural-1 (NS1 glycoprotein candidate vaccine also reacted with both DENV envelope (E glycoproteins and blood-clotting proteins. New xKGSx/xSGKx amino acid motifs were identified on DENV-2 glycoproteins, HIV-1 gp41 and factor IXa. Their potential roles in DENV and HIV-1 antibody-enhanced replication (AER and auto-immunity were assessed. In this study, a RADS values were determined for MAbs and PAbs, generated in congeneic (H2: class II mice against DENV NS1 glycoprotein epitopes, to account for their cross-reaction patterns, and b MAb 1G5.3 reactions with xKGSx/xSGKx motifs present in the DENV-4 NS1, E and HIV-1 glycoproteins and factor IXa were assessed after the introduction of amino acid substitutions, deletions, or intra-/inter-cysteine (C-C bridges. Results MAbs 1H7.4, 5H4.3, 3D1.4 and 1G5.3 had high (4.23- to 16.83-fold RADS values against single epitopes on the DENV-2 NS1 glycoprotein, and MAb 3D1.4 defined the DENV complex-conserved LX1 epitope. In contrast, MAbs 1G5.4-A1-C3 and 1C6.3 had low (0.47- to 1.67-fold RADS values against multiple epitopes. PAb DENV complex-reactions occurred through moderately-high (2.77- and 3.11-fold RADS values against the LX1 epitope. MAb 1G5.3 reacted with xSGKx motifs present in DENV-4 NS1 and E glycoproteins, HIV-1 gp41 and factor IXa, while natural C-C bridge formations or

  13. The role of heparan sulfate deficiency in autistic phenotype: potential involvement of Slit/Robo/srGAPs-mediated dendritic spine formation. (United States)

    Pérez, Christine; Sawmiller, Darrell; Tan, Jun


    Autism Spectrum Disorders (ASD) are the second most common developmental cause of disability in the United States. ASDs are accompanied with substantial economic and emotional cost. The brains of ASD patients have marked structural abnormalities, in the form of increased dendritic spines and decreased long distance connections. These structural differences may be due to deficiencies in Heparin Sulfate (HS), a proteoglycan involved in a variety of neurodevelopmental processes. Of particular interest is its role in the Slit/Robo pathway. The Slit/Robo pathway is known to be involved in the regulation of axonal guidance and dendritic spine formation. HS mediates the Slit/Robo interaction; without its presence Slit's repulsive activity is abrogated. Slit/Robo regulates dendritic spine formation through its interaction with srGAPs (slit-robo GTPase Activating Proteins), which leads to downstream signaling, actin cytoskeleton depolymerization and dendritic spine collapse. Through interference with this pathway, HS deficiency can lead to excess spine formation.

  14. Volatilization of low vapor pressure--volatile organic compounds (LVP-VOCs) during three cleaning products-associated activities: Potential contributions to ozone formation. (United States)

    Shin, Hyeong-Moo; McKone, Thomas E; Bennett, Deborah H


    There have been many studies to reduce ozone formation mostly from volatile organic compound (VOC) sources. However, the role of low vapor pressure (LVP)-VOCs from consumer products remains mostly unexplored and unaddressed. This study explores the impact of high production volume LVP-VOCs on ozone formation from three cleaning products-associated activities (dishwashing, clothes washing, and surface cleaning). We develop a model framework to account for the portion available for ozone formation during the use phase and from the down-the-drain disposal. We apply experimental studies that measured emission rates or models that were developed for estimating emission rates of organic compounds during the use phase. Then, the fraction volatilized (fvolatilized) and the fraction disposed down the drain (fdown-the-drain) are multiplied by the portion available for ozone formation for releases to the outdoor air (fO3|volatilized) and down-the-drain (fO3|down-the-drain), respectively. Overall, for chemicals used in three specific cleaning-product uses, fvolatilized is less than 0.6% for all studied LVP-VOCs. Because greater than 99.4% of compounds are disposed of down the drain during the use phase, when combined with fO3|volatilized and fO3|down-the-drain, the portion available for ozone formation from the direct releases to outdoor air and the down-the-drain disposal is less than 0.4% and 0.2%, respectively. The results from this study indicate that the impact of the studied LVP-VOCs on ozone formation is very sensitive to what occurs during the use phase and suggest the need for future research on experimental work at the point of use.

  15. Potential for formation of disinfection by-products from storage of chlorinated surface water in the Basalt aquifer near Fallon, Nevada (United States)

    Fram, Miranda S.; Maurer, Douglas K.; Lico, Michael S.


    Increased pumpage from a basalt aquifer near Fallon, Nevada, has caused its water levels to decline and has induced changes in the quality of water pumped from the basalt. The aquifer is the sole source of water for municipal supply to the city of Fallon, the Naval Air Station Fallon, and the Fallon Paiute-Shoshone Tribe. These changes may be mitigated by storage of surface water in the basalt for subsequent use. Because chlorination of the surface water may be required for storage, the U.S. Geological Survey, in cooperation with the Fallon Paiute-Shoshone Tribe, made laboratory tests using laboratory carbon-organic-free water, surface-water, ground-water, and basaltic-rock samples to determine the potential for formation of disinfection by-products. Experiments with water samples only (no rock and no chlorine) indicated no change in dissolved-organic-carbon (DOC) concentrations over a 20-day reaction period; whereas, all experiments using rock, water, and no chlorine indicated an increase in DOC concentrations. The greatest increase in DOC concentrations for all three water samples occurred in experiments with the rock samples from outcrops on Rattlesnake Hill. Experiments with water only and chlorine yielded a total trihalomethane (THM) concentration of 97.4 ?g/L for the ground-water sample and 347 ?g/L for the surface-water sample. Experiments with mixtures of water, rocks, and chlorine indicated that reactions with the rock consumed chlorine and released significant amounts of organic carbon from the rock, increasing the DOC concentration in the water. The organic carbon in the rocks likely is associated with the secondary clay minerals that line vesicles and fractures in the rocks. THM concentrations were greatest, from 335 to 909 ?g/L, for surface water equilibrated with rock samples from Rattlesnake Hill. However, the concentration of chlorine required to produce these high THM concentrations ranged from 18 to 84 mg/L. The results of the experiments suggest

  16. The Process of Creating a Cross-University Network for Formative and Shared Assessment in Higher Education in Spain and Its Potential Applications (United States)

    Lopez-Pastor, Victor M.; Castejon, Javier; Sicilia-Camacho, Alvaro; Navarro-Adelantado, Vicente; Webb, Graham


    During the academic year 2005-2006 a Cross University Network for Formative and Shared Assessment in Higher Education was formed among 48 academics from 16 different universities within Spain and representing a range of academic areas. The Network was formed in response to the determination of a group of individuals who were dissatisfied with, or…

  17. Model study of local enhancement of chemical potential gradient after facet formation on growing spherical Cu 2-δSe crystals (United States)

    Lovrić, Davorin; Vučić, Zlatko; Gladić, Jadranko


    The growth of spherical copper selenide single crystals (fed by Cu atoms at constant rate) is driven by the gradient of the chemical potential, which is in the absence of facets isotropic and proportional to inverse square of crystal radius. We investigate the influence of the facets on the local chemical potential gradient on the facet site by a model based on diffusion of Cu atoms with appropriate boundary conditions. The average chemical potential gradient decreases as crystal grows, acquiring values that are, except for the initial growing period, below the threshold value for activation of 2D nucleation. We show that in spite of this fact the local chemical potential gradient, due to the facet presence, may acquire large values, sufficient to activate 2D nucleation and to justify the occurrence of the growing mode consisting of alternation of time intervals of facet vertical growth with those in which facet does not advance, as has been preliminary detected in our experiments.

  18. Immunity related genes in dipterans share common enrichment of AT-rich motifs in their 5' regulatory regions that are potentially involved in nucleosome formation

    Directory of Open Access Journals (Sweden)

    Rodriguez Mario H


    Full Text Available Abstract Background Understanding the transcriptional regulation mechanisms in response to environmental challenges is of fundamental importance in biology. Transcription factors associated to response elements and the chromatin structure had proven to play important roles in gene expression regulation. We have analyzed promoter regions of dipteran genes induced in response to immune challenge, in search for particular sequence patterns involved in their transcriptional regulation. Results 5' upstream regions of D. melanogaster and A. gambiae immunity-induced genes and their corresponding orthologous genes in 11 non-melanogaster drosophilid species and Ae. aegypti share enrichment in AT-rich short motifs. AT-rich motifs are associated with nucleosome formation as predicted by two different algorithms. In A. gambiae and D. melanogaster, many immunity genes 5' upstream sequences also showed NFκB response elements, located within 500 bp from the transcription start site. In A. gambiae, the frequency of ATAA motif near the NFκB response elements was increased, suggesting a functional link between nucleosome formation/remodelling and NFκB regulation of transcription. Conclusion AT-rich motif enrichment in 5' upstream sequences in A. gambiae, Ae. aegypti and the Drosophila genus immunity genes suggests a particular pattern of nucleosome formation/chromatin organization. The co-occurrence of such motifs with the NFκB response elements suggests that these sequence signatures may be functionally involved in transcriptional activation during dipteran immune response. AT-rich motif enrichment in regulatory regions in this group of co-regulated genes could represent an evolutionary constrained signature in dipterans and perhaps other distantly species.

  19. Formate Formation and Formate Conversion in Biological Fuels Production

    Directory of Open Access Journals (Sweden)

    Bryan R. Crable


    Full Text Available Biomethanation is a mature technology for fuel production. Fourth generation biofuels research will focus on sequestering CO2 and providing carbon-neutral or carbon-negative strategies to cope with dwindling fossil fuel supplies and environmental impact. Formate is an important intermediate in the methanogenic breakdown of complex organic material and serves as an important precursor for biological fuels production in the form of methane, hydrogen, and potentially methanol. Formate is produced by either CoA-dependent cleavage of pyruvate or enzymatic reduction of CO2 in an NADH- or ferredoxin-dependent manner. Formate is consumed through oxidation to CO2 and H2 or can be further reduced via the Wood-Ljungdahl pathway for carbon fixation or industrially for the production of methanol. Here, we review the enzymes involved in the interconversion of formate and discuss potential applications for biofuels production.

  20. The potential of chemical fingerprinting of tephra for stratigraphic correlations in the fossil Lagerstätte of the Pisco Formation (Peru) (United States)

    Bosio, Giulia; Gioncada, Anna; Malinverno, Elisa; Villa, Igor Maria; Di Celma, Claudio; Gariboldi, Karen; Urbina, Mario; Bianucci, Giovanni


    The upper Miocene Pisco Formation (Peru) represents a world-known fossil Lagerstätte containing abundant and exceptionally well-preserved marine vertebrates. A detailed chronostratigraphic reconstruction is indispensable to study this fossil record and to understand the evolution of marine vertebrates. Recent work (Bianucci et al., 2016; Di Celma et al., 2016; Gariboldi et al., in press) in the area of the western Ica River Valley defined a detailed chronostratigraphic framework for the Pisco Formation, containing all the fossil vertebrates observed in the area. Such chronostratigraphic framework, based on new 40Ar/39Ar ages on biotite from tephra layers integrated with diatom biostratigraphy, implements previous scattered radiometric data (Brand et al., 2011; Esperante et al., 2015). Tephra layers representing primary air-fall deposition of volcanic ash from the Peruvian Andes volcanoes are very frequent in the Pisco Formation. Several of them do not show evidence of reworking or bioturbation. Due to their regional dispersal and to their geologically instantaneous deposition (Lowe, 2011), they provide the opportunity not only to date specific layers, when suitable for radiometric age determination, but also to correlate different localities, through the chemical fingerprinting of tephra. We collected more than 200 tephra layers from different localities in the Ica Desert along six measured stratigraphic sections. Based on the estimated stratigraphic position, we analyzed specific tephra layers through petrographic characterization, glass shard morphology, electron probe microanalyses of glass shards and, where present, biotite crystals. Despite some difficulties encountered, such as similar magma or mineral composition, local weathering, lack of record due to marine current transport and change in depositional environments among different localities, the correspondence of the obtained data allowed to verify correlations that were supposed during field work and to

  1. Oxidative Deamination of Serum Albumins by (--Epigallocatechin-3-O-Gallate: A Potential Mechanism for the Formation of Innate Antigens by Antioxidants.

    Directory of Open Access Journals (Sweden)

    Yukinori Hatasa

    Full Text Available (--Epigallocatechin-3-O-gallate (EGCG, the most abundant polyphenol in green tea, mediates the oxidative modification of proteins, generating protein carbonyls. However, the underlying molecular mechanism remains unclear. Here we analyzed the EGCG-derived intermediates generated upon incubation with the human serum albumin (HSA and established that EGCG selectively oxidized the lysine residues via its oxidative deamination activity. In addition, we characterized the EGCG-oxidized proteins and discovered that the EGCG could be an endogenous source of the electrically-transformed proteins that could be recognized by the natural antibodies. When HSA was incubated with EGCG in the phosphate-buffered saline (pH 7.4 at 37°C, the protein carbonylation was associated with the formation of EGCG-derived products, such as the protein-bound EGCG, oxidized EGCG, and aminated EGCG. The aminated EGCG was also detected in the sera from the mice treated with EGCG in vivo. EGCG selectively oxidized lysine residues at the EGCG-binding domains in HSA to generate an oxidatively deaminated product, aminoadipic semialdehyde. In addition, EGCG treatment results in the increased negative charge of the protein due to the oxidative deamination of the lysine residues. More strikingly, the formation of protein carbonyls by EGCG markedly increased its cross-reactivity with the natural IgM antibodies. These findings suggest that many of the beneficial effects of EGCG may be partly attributed to its oxidative deamination activity, generating the oxidized proteins as a target of natural antibodies.

  2. Utilization of the serosal scarification model of postoperative intestinal adhesion formation to investigate potential adhesion-preventing substances in the rabbit. (United States)

    Singer, E R; Livesey, M A; Barker, I K; Hurtig, M B; Conlon, P D


    A rabbit serosal scarification model was utilized to compare the ability of four drugs, previously administered peri-operatively to horses undergoing exploratory celiotomy, to prevent the development of postoperative intestinal adhesions. The substances compared were 32% Dextran 70 (7 mL/kg), 1% sodium carboxymethylcellulose (7 mL/kg), trimethoprim-sulfadiazine (30 mg/kg), and flunixin meglumine (1 mg/kg). The first two were administered intra-abdominally following surgery, while the latter two were administered systemically in the peri-operative period. Fibrous adhesions were evident in all animals in the untreated serosal scarification group. No significant difference in the number of animals with adhesions was found between the untreated control group and any treatment group, nor among the treatment groups. Microscopic examination of adhesions collected at postmortem examination revealed fibers consistent with cotton, surrounded by a giant-cell reaction and ongoing acute inflammation. The source of the fibers was likely the cotton laparotomy sponges used to scarify the intestinal surface, since the pattern in the granuloma and sponge fibers appeared similar under polarized light. Though consistent intestinal adhesion formation was produced in the rabbit, the presence of foreign body granulomas may prevent consideration of this model for future research. The drugs tested were ineffective in preventing the formation of postoperative small intestinal adhesions in this model. Images Figure 1. Figure 2. Figure 3. PMID:8904667

  3. Replication methods and tools in high-throughput cultivation processes - recognizing potential variations of growth and product formation by on-line monitoring

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    Luft Karina


    Full Text Available Abstract Background High-throughput cultivations in microtiter plates are the method of choice to express proteins from recombinant clone libraries. Such processes typically include several steps, whereby some of them are linked by replication steps: transformation, plating, colony picking, preculture, main culture and induction. In this study, the effects of conventional replication methods and replication tools (8-channel pipette, 96-pin replicators: steel replicator with fixed or spring-loaded pins, plastic replicator with fixed pins on growth kinetics of Escherichia coli SCS1 pQE-30 pSE111 were observed. Growth was monitored with the BioLector, an on-line monitoring technique for microtiter plates. Furthermore, the influence of these effects on product formation of Escherichia coli pRhotHi-2-EcFbFP was investigated. Finally, a high-throughput cultivation process was simulated with Corynebacterium glutamicum pEKEx2-phoD-GFP, beginning at the colony picking step. Results Applying different replication tools and methods for one single strain resulted in high time differences of growth of the slowest and fastest growing culture. The shortest time difference (0.3 h was evaluated for the 96 cultures that were transferred with an 8-channel pipette from a thawed and mixed cryoculture and the longest time difference (6.9 h for cultures that were transferred with a steel replicator with fixed pins from a frozen cryoculture. The on-line monitoring of a simulated high-throughput cultivation process revealed strong variances in growth kinetics and a twofold difference in product formation. Another experiment showed that varying growth kinetics, caused by varying initial biomass concentrations (OD600 of 0.0125 to 0.2 led to strongly varying product formation upon induction at a defined point of time. Conclusions To improve the reproducibility of high-throughput cultivation processes and the comparability between different applied cultures, it is strongly

  4. Visualization of space competition and plume formation with complex potentials for multiple source flows: Some examples and novel application to Chao lava flow (Chile)

    NARCIS (Netherlands)

    Weijermars, R.


    Fluid displacement in a continuum pressured by a variable constellation of source flows can be visualized as solutions of line integrals. The algorithms are based on complex potentials that provide exact solutions of the Navier-Stokes equation and allow users to specify both the location and flux st

  5. Potential function of added minerals as nucleation sites and effect of humic substances on mineral formation by the nitrate-reducing Fe(II)-oxidizer Acidovorax sp. BoFeN1. (United States)

    Dippon, Urs; Pantke, Claudia; Porsch, Katharina; Larese-Casanova, Phil; Kappler, Andreas


    The mobility of toxic metals and the transformation of organic pollutants in the environment are influenced and in many cases even controlled by iron minerals. Therefore knowing the factors influencing iron mineral formation and transformation by Fe(II)-oxidizing and Fe(III)-reducing bacteria is crucial for understanding the fate of contaminants and for the development of remediation technologies. In this study we followed mineral formation by the nitrate-reducing Fe(II)-oxidizing strain Acidovorax sp. BoFeN1 in the presence of the crystalline Fe(III) (oxyhydr)oxides goethite, magnetite and hematite added as potential nucleation sites. Mössbauer spectroscopy analysis of minerals precipitated by BoFeN1 in (57)Fe(II)-spiked microbial growth medium showed that goethite was formed in the absence of mineral additions as well as in the presence of goethite or hematite. The presence of magnetite minerals during Fe(II) oxidation induced the formation of magnetite in addition to goethite, while the addition of humic substances along with magnetite also led to goethite but no magnetite. This study showed that mineral formation not only depends on the aqueous geochemical conditions but can also be affected by the presence of mineral nucleation sites that initiate precipitation of the same underlying mineral phases.

  6. Storage Utsira. Analysis of potentials and costs of storage of CO{sub 2} in the Utsira formation. Country report - Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Grohnheit, P.E.


    This report is the main deliverable for Denmark in the project 'Analysis of potentials and costs of storage of CO{sub 2} in the Utsira Aquifer in the North Sea'. The project is funded by within FENCO-ERA, which is an EU network for national R and D activities in 13 countries in the field of fossil energy conversion and CO{sub 2} capture and storage (CCS). The project aims to analyze potential and costs of storage of CO{sub 2} in the Utsira aquifer in the North Sea for five countries surrounding the North Sea. So far, there has been very little interest in CCS in Denmark. The technology is not a part of public policy, and the Government has not expressed any official standpoint on the use of CCS in Denmark. On the other hand, both the electricity industry and geologists from the Geological Survey of Denmark and Greenland (GEUS) have been active in international research on both capture and storage. A very significant additional constraint for CCS in Denmark is the planned development of wind power, which will further reduce the need for base-load thermal electricity generation. For the model analysis in the Storage Utsira project it means that the potential for CCS is becoming increasingly constrained. To model these constraints, it means that the Pan European TIMES model, which has a structure that is harmonised to meet the requirements for 30 European countries, must be calibrated in further details to give a proper representation of the constrained potential for Denmark. It is unlikely that Denmark will need the CO{sub 2} storage capacity in Utsira within the time horizon of the study. However, in co-operation with other countries around the North Sea, the Danish potential for carbon storage may contribute to the build-up of the long-distance CO{sub 2} transport infrastructure. (ln)

  7. Theoretical studies on atmospheric chemistry of HFE-245mc and perfluoro-ethyl formate: Reaction with OH radicals, atmospheric fate of alkoxy radical and global warming potential (United States)

    Lily, Makroni; Baidya, Bidisha; Chandra, Asit K.


    Theoretical studies have been performed on the kinetics, mechanism and thermochemistry of the hydrogen abstraction reactions of CF3CF2OCH3 (HFE-245mc) and CF3CF2OCHO with OH radical using DFT based M06-2X method. IRC calculation shows that both hydrogen abstraction reactions proceed via weakly bound hydrogen-bonded complex preceding to the formation of transition state. The rate coefficients calculated by canonical transition state theory along with Eckart's tunnelling correction at 298 K: k1(CF3CF2OCH3 + OH) = 1.09 × 10-14 and k2(CF3CF2OCHO + OH) = 1.03 × 10-14 cm3 molecule-1 s-1 are in very good agreement with the experimental values. The atmospheric implications of CF3CF2OCH3 and CF3CF2OCHO are also discussed.

  8. Formative assessment in Swedish mathematics classroom practice


    Andersson, Catarina; Boström, Erika


    International audience; Using formative assessment has woken interest in many countries because of the potential effect on student achievement. To investigate Swedish teachers' use of formative assessment in mathematics, this study used classroom observations and teacher interviews of 38 mathematics teachers. The teachers used formative assessment, but additional formative activities could support teachers to better take advantage of the potential in using formative assessment.

  9. Experimental hypothyroidism delays field excitatory post-synaptic potentials and disrupts hippocampal long-term potentiation in the dentate gyrus of hippocampal formation and Y-maze performance in adult rats. (United States)

    Artis, A S; Bitiktas, S; Taşkın, E; Dolu, N; Liman, N; Suer, C


    Manipulations of thyroid hormones have been shown to influence learning and memory. Although a large body of literature is available on the effect of thyroid hormone deficiency on learning and memory functions during the developmental stage, electrophysiological and behavioural findings, particularly on propylthiouracil administration to adult normothyroid animals, are not satisfactory. The experiments in the present study were carried out on 12 adult male Wistar rats aged 6-7 months. Hypothyroidism was induced by administering 6-n-propyl-2-thiouracil in their drinking water for 21 days at a concentration of 0.05%. The spatial learning performance of hypothyroid and control rats was studied on a Y-maze. The rats were then placed in a stereotaxic frame under urethane anaesthesia. A bipolar tungsten electrode was used to stimulate the medial perforant path. A glass micropipette was inserted into the granule cell layer of the ipsilateral dentate gyrus to record field excitatory post-synaptic potentials. After a 15-min baseline recording of field potentials, long-term potentiation was induced by four sets of tetanic trains. The propylthiouracil-treated rats showed a significantly attenuated input-output (I/O) relationship when population spike (PS) amplitudes and field excitatory post-synaptic potentials (fEPSP) were compared. fEPSP and PS latencies were found to be longer in the hypothyroid group than in the control group. The PS amplitude and fEPSP slope potentiations in the hypothyroid rats were not statistically different from those in the control rats, except for the field EPSP slope measured in the post-tetanic and maintenance phases. The hypothyroid rats also showed lower thyroxine levels and poor performance in the spatial memory task. The present study provides in vivo evidence for the action of propylthiouracil leading to impaired synaptic plasticity, which might explain deficit in spatial memory tasks in adult hypothyroid rats.

  10. Broad-spectrum antimicrobial photocatalysis mediated by titanium dioxide and UVA is potentiated by addition of bromide ion via formation of hypobromite. (United States)

    Wu, Ximing; Huang, Ying-Ying; Kushida, Yu; Bhayana, Brijesh; Hamblin, Michael R


    Antimicrobial photocatalysis involves the UVA excitation of titanium dioxide (TiO2) nanoparticles (particularly the anatase form) to produce reactive oxygen species (ROS) that kill microbial cells. For the first time we report that the addition of sodium bromide to photoactivated TiO2 (P25) potentiates the killing of Gram-positive, Gram-negative bacteria and fungi by up to three logs. The potentiation increased with increasing bromide concentration in the range of 0-10mM. The mechanism of potentiation is probably due to generation of both short and long-lived oxidized bromine species including hypobromite as shown by the following observations. There is some antimicrobial activity remaining in solution after switching off the light, that lasts for 30min but not 2h, and oxidizes 3,3',5,5'-tetramethylbenzidine. N-acetyl tyrosine ethyl ester was brominated in a light dose-dependent manner, however no bromine or tribromide ion could be detected by spectrophotometry or LC-MS. The mechanism appears to have elements in common with the antimicrobial system (myeloperoxidase+hydrogen peroxide+bromide).

  11. Formation of reactive nitrogen species during peroxidase-catalyzed oxidation of nitrite. A potential additional mechanism of nitric oxide-dependent toxicity. (United States)

    van der Vliet, A; Eiserich, J P; Halliwell, B; Cross, C E


    Involvement of peroxynitrite (ONOO-) in inflammatory diseases has been implicated by detection of 3-nitrotyrosine, an allegedly characteristic protein oxidation product, in various inflamed tissues. We show here that nitrite (NO2-), the primary metabolic end product of nitric oxide (NO.), can be oxidized by the heme peroxidases horseradish peroxidase, myeloperoxidase (MPO), and lactoperoxidase (LPO), in the presence of hydrogen peroxide (H2O2), to most likely form NO.2, which can also contribute to tyrosine nitration during inflammatory processes. Phenolic nitration by MPO-catalyzed NO2- oxidation is only partially inhibited by chloride (Cl-), the presumed major physiological substrate for MPO. In fact, low concentrations of NO2- (2-10 microM) catalyze MPO-mediated oxidation of Cl-, indicated by increased chlorination of monochlorodimedon or 4-hydroxyphenylacetic acid, most likely via reduction of MPO compound II. Peroxidase-catalyzed oxidation of NO2-, as indicated by phenolic nitration, was also observed in the presence of thiocyanate (SCN-), an alternative physiological substrate for mammalian peroxidases. Collectively, our results suggest that NO2-, at physiological or pathological levels, is a substrate for the mammalian peroxidases MPO and lactoperoxidase and that formation of NO2. via peroxidase-catalyzed oxidation of NO2- may provide an additional pathway contributing to cytotoxicity or host defense associated with increased NO. production.

  12. Effects of water-filtered infrared-A and of heat on cell death, inflammation, antioxidative potential and of free radical formation in viable skin--first results. (United States)

    Piazena, Helmut; Pittermann, Wolfgang; Müller, Werner; Jung, Katinka; Kelleher, Debra K; Herrling, Thomas; Meffert, Peter; Uebelhack, Ralf; Kietzmann, Manfred


    The effects of water-filtered infrared-A (wIRA) and of convective heat on viability, inflammation, inducible free radicals and antioxidative power were investigated in natural and viable skin using the ex vivo Bovine Udder System (BUS) model. Therefore, skin samples from differently treated parts of the udder of a healthy cow were analyzed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test, by prostaglandin E2 (PGE2) measurement and by electron spin resonance (ESR) spectroscopy. Neither cell viability, the inflammation status, the radical status or the antioxidative defence systems of the skin were significantly affected by wIRA applied within 30 min by using an irradiance of 1900 W m(-2) which is of relevance for clinical use, but which exceeded the maximum solar IR-A irradiance at the Earth's surface more than 5 times and which resulted in a skin surface temperature of about 45 °C without cooling and of about 37 °C with convective cooling by air ventilation. No significant effects on viability and on inflammation were detected when convective heat was applied alone under equivalent conditions in terms of the resulting skin surface temperatures and exposure time. As compared with untreated skin, free radical formation was almost doubled, whereas the antioxidative power was reduced to about 50% after convective heating to about 45 °C.

  13. Chemical composition of fragmental products fractions of rock dumps and tailing dump as basis for potential geoecological danger estimation in the areas of mining enterprises

    Directory of Open Access Journals (Sweden)

    Vdovina Ol’ga Konstantinovna

    Full Text Available Negative consequences of deposit development on the environment are well know. They manifest themselves most intensively in case of open-cut mining of ore minerals, which is related to the increase of rock dumps masses. The material of rock dumps and tailing dumps actively influence the state of the environment transforming the natural landscapes, first of all, as a reason of migration of waters changed as a result of their contact with mining waste. The authors give their estimation of the consequences of apatite-nephelinic ore crop in Khibini Ore District by the company “Apatit”, which includes the influence on the natural waters. The unique natural conditions of the area are the reason for high-level potential geoecological danger. The mobility of lots of toxic elements is raised because of ligand-ion OH in the waters of alkali rocks of Khibini soil.

  14. Effect of Applied Potential on the Formation of Self-Organized TiO2 Nanotube Arrays and Its Photoelectrochemical Response

    Directory of Open Access Journals (Sweden)

    Chin Wei Lai


    Full Text Available Self-organized TiO2 nanotube arrays have been fabricated by anodization of Ti foil in an electrochemical bath consisting of 1 M of glycerol with 0.5 wt% of NH4F. The effects of applied potential on the resulting nanotubes were illustrated. Among all of the applied potentials, 30 V resulted in the highest uniformity and aspect ratio TiO2 nanotube arrays with the tube's length approximately 1 μm and pore's size of 85 nm. TiO2 nanotube arrays were amorphous in as-anodized condition. The anatase phase was observed after annealing at 400∘C in air atmosphere. The effect of crystallization and effective surface area of TiO2 nanotube arrays in connection with the photoelectrochemical response was reported. Photoelectrochemical response under illumination was enhanced by using the annealed TiO2 nanotube arrays which have larger effective surface area to promote more photoinduced electrons.

  15. Man o' War Mutation in UDP-α-D-Xylose Synthase Favors the Abortive Catalytic Cycle and Uncovers a Latent Potential for Hexamer Formation

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, Jr., Richard M.; Polizzi, Samuel J.; Kadirvelraj, Renuka; Howard, Wesley W.; Wood, Zachary A. [Georgia


    The man o’ war (mow) phenotype in zebrafish is characterized by severe craniofacial defects due to a missense mutation in UDP-α-D-xylose synthase (UXS), an essential enzyme in proteoglycan biosynthesis. The mow mutation is located in the UXS dimer interface ~16 Å away from the active site, suggesting an indirect effect on the enzyme mechanism. We have examined the structural and catalytic consequences of the mow mutation (R236H) in the soluble fragment of human UXS (hUXS), which shares 93% sequence identity with the zebrafish enzyme. In solution, hUXS dimers undergo a concentration-dependent association to form a tetramer. Sedimentation velocity studies show that the R236H substitution induces the formation of a new hexameric species. Using two new crystal structures of the hexamer, we show that R236H and R236A substitutions cause a local unfolding of the active site that allows for a rotation of the dimer interface necessary to form the hexamer. The disordered active sites in the R236H and R236A mutant constructs displace Y231, the essential acid/base catalyst in the UXS reaction mechanism. The loss of Y231 favors an abortive catalytic cycle in which the reaction intermediate, UDP-α-D-4-keto-xylose, is not reduced to the final product, UDP-α-D-xylose. Surprisingly, the mow-induced hexamer is almost identical to the hexamers formed by the deeply divergent UXS homologues from Staphylococcus aureus and Helicobacter pylori (21% and 16% sequence identity, respectively). The persistence of a latent hexamer-building interface in the human enzyme suggests that the ancestral UXS may have been a hexamer.

  16. Dimethylamine Addition to Formaldehyde Catalyzed by a Single Water Molecule: A Facile Route for Atmospheric Carbinolamine Formation and Potential Promoter of Aerosol Growth. (United States)

    Louie, Matthew K; Francisco, Joseph S; Verdicchio, Marco; Klippenstein, Stephen J; Sinha, Amitabha


    We use ab initio calculations to investigate the energetics and kinetics associated with carbinolamine formation resulting from the addition of dimethylamine to formaldehyde catalyzed by a single water molecule. Further, we compare the energetics for this reaction with that for the analogous reactions involving methylamine and ammonia separately. We find that the reaction barrier for the addition of these nitrogen-containing molecules onto formaldehyde decreases along the series ammonia, methylamine, and dimethylamine. Hence, starting with ammonia, the reaction barrier can be "tuned" by the substitution of an alkyl group in place of a hydrogen atom. The reaction involving dimethylamine has the lowest barrier with the transition state being 5.4 kcal/mol below the (CH3)2NH + H2CO + H2O separated reactants. This activation energy is significantly lower than that for the bare reaction occurring without water, H2CO + (CH3)2NH, which has a barrier of 20.1 kcal/mol. The negative barrier associated with the single-water molecule catalyzed reaction of dimethylamine with H2CO to form the carbinolamine (CH3)2NCH2OH suggests that this reaction should be energetically feasible under atmospheric conditions. This is confirmed by rate calculations which suggest that the reaction will be facile even in the gas phase. As amines and oxidized organics containing carbonyl functional groups are common components of secondary organic aerosols, the present finding has important implications for understanding how larger, less volatile organic compounds can be generated in the atmosphere by combining readily available smaller components as required for promoting aerosol growth.

  17. A quantitative evaluation of gross versus histologic neuroma formation in a rabbit forelimb amputation model: potential implications for the operative treatment and study of neuromas

    Directory of Open Access Journals (Sweden)

    Kuiken Todd A


    Full Text Available Abstract Background Surgical treatment of neuromas involves excision of neuromas proximally to the level of grossly "normal" fascicles; however, proximal changes at the axonal level may have both functional and therapeutic implications with regard to amputated nerves. In order to better understand the retrograde "zone of injury" that occurs after nerve transection, we investigated the gross and histologic changes in transected nerves using a rabbit forelimb amputation model. Methods Four New Zealand White rabbits underwent a forelimb amputation with transection and preservation of the median, radial, and ulnar nerves. After 8 weeks, serial sections of the amputated nerves were then obtained in a distal-to-proximal direction toward the brachial plexus. Quantitative histomorphometric analysis was performed on all nerve specimens. Results All nerves demonstrated statistically significant increases in nerve cross-sectional area between treatment and control limbs at the distal nerve end, but these differences were not observed 10 mm more proximal to the neuroma bulb. At the axonal level, an increased number of myelinated fibers were seen at the distal end of all amputated nerves. The number of myelinated fibers progressively decreased in proximal sections, normalizing at 15 mm proximally, or the level of the brachial plexus. The cross-sectional area of myelinated fibers was significantly decreased in all sections of the treatment nerves, indicating that atrophic axonal changes proceed proximally at least to the level of the brachial plexus. Conclusions Morphologic changes at the axonal level extend beyond the region of gross neuroma formation in a distal-to-proximal fashion after nerve transection. This discrepancy between gross and histologic neuromas signifies the need for improved standardization among neuroma models, while also providing a fresh perspective on how we should view neuromas during peripheral nerve surgery.

  18. 腐殖酸氯消毒副产物生成潜力评估指标的研究%Assessment parameter for disinfection by-products formation potential of humic acids

    Institute of Scientific and Technical Information of China (English)

    吴颖虹; 张明月; 李楠; 商博东; 白世基


    目的 探讨腐殖酸氯消毒副产物生成潜力评估指标.方法 选用2种商品腐殖酸和1种提取自活性污泥的腐殖酸作为目标物( 1.67~10 mg/L)进行氯化消毒过程的实验室模拟研究,检测254 nm紫外吸光度(UV254)、总有机碳(TOC)、三卤甲烷(THMs)、卤代乙酸(HAAs)并进行线性拟合.结果 3种腐殖酸在氯化消毒过程中均能产生THMs和HAAs,其中THMs的生产潜力为11.63~43.61 μg/mg TOC,HAAs的生产潜力为11.03~24.06 μg/mg TOC.HAAs的生成潜力与单位TOC的腐殖酸254 nm紫外吸收(SUVA)具有较好相关性(P<0.05).采用SUVA与腐殖酸氧含量的乘积作为参数,与THMs类物质的产生具有更好的相关性(P<0.05).结论 三氯甲烷和氯乙酸(二氯乙酸、三氯乙酸、一氯乙酸)分别是主要的THMs和HAAs类氯消毒副产物.SUVA和SUVA与腐殖酸氧含量的乘积可分别用作氯消毒过程中HAAs和THMs类副产物生成潜力的评价指标.%Objective To study the formation potential of disinfection by-products of huraic acid. Methods Two different commercial humic acids and one humic acid extracted from activated sludge were selected as the target substances in this study and the simulated experiments were conducted. Results Formation of trihalomethanes (THMs) and haloacetic acids (HAAs) was observed in all systems containing each of the three humic acids, while the THMs formation potential ranged from 11.63-43.61 μg/mg TOC, and the HAAs 11.03-24.06 μg/mg TOC. Formation potential of HAAs was highly related to per unit of TOC's ultraviolet absorption at 254 nm (SUVA) of each humic acid. However, the product of SUVA and oxygen content of humic acid (SUVA×O%) was found more suitable to fix the formation potential of THMs. Conclusion Trichloromethane and dichloro-, trichloro-, chloro-acetic acids were the main by-products belonging to THMs and HAAs respectively. Values of SUVA and(SUVA×O%) can be used as the indexes to assess the formation potential of

  19. Neo-mineral formation during artificial coalification of low-ash - mineral free-peat material from tropical Malaysia-potential explanation for low ash coals

    Energy Technology Data Exchange (ETDEWEB)

    Wuest, Raphael [School of Earth and Environmental Sciences, James Cook University, Townsville, 4811, QLD (Australia); Bustin, R. Marc; Ross, John [Department of Earth and Ocean Sciences, University of British Columbia, 6339 Stores Road, Vancouver, B.C. (Canada)


    Abundant coal deposits have very low inorganic contents (ash yield; < 2%) and hence are almost ash-free. Inexplicable to date is that the precursor of coal, modern peat deposits, almost nowhere have such low ash yields as a result of both the inorganic mineral and biogenic phytolith contents. However, despite the common occurrence of phytoliths in modern peats, they are invariably absent in coals. It has thus been hypothesized by some investigators that modern environments are not ideal analogues for the formation of low ash coal deposits. Here we present new evidence to suggest that mineral diagenesis during coalification can transform biogenic inorganics to new minerals and that a substantial component of these new minerals could be removed in solution during expulsion of moisture with coalification resulting in low ash precursors of coal. This study presents results from artificial coalification experiments of modern tropical forest peat material with ash yields between 2-4.3 wt.%. The inorganic material of the peat consists almost exclusively of Al-Si-and Si-rich phytoliths and other bioliths; no other inorganic mineral matter is present. Compressed pellets of dried peat were deformed in a Griggs constant strain rate apparatus at a constant confining pressure of 5 kb and constant strain rate of 10{sup -} {sup 5} s {sup -} {sup 1} at variable temperatures from 350 C to 550 C. The samples, exposed to artificial coalification processes, were then analysed by SEM, EDS, and XRD for semi-quantitative chemical analyses. The deformed material showed a lack of any biogenic silica and Al-Si-phytoliths, but contained neoformed idiomorphic quartz crystals and clays. We conclude that modern peat forming environments that have low-ash peats containing biogenic silica and other biogenic Al-Si-material can represent precursors of very low-ash coal deposits. Our experiments illustrate that during coalification, it is likely all or almost all biogenic material is transformed

  20. Impact of aftertreatment devices on primary emissions and secondary organic aerosol formation potential from in-use diesel vehicles: results from smog chamber experiments

    Directory of Open Access Journals (Sweden)

    R. Chirico


    Full Text Available Diesel particulate matter (DPM is a significant source of aerosol in urban areas and has been linked to adverse health effects. Although newer European directives have introduced increasingly stringent standards for primary PM emissions, gaseous organics emitted from diesel cars can still lead to large amounts of secondary organic aerosol (SOA in the atmosphere. Here we present results from smog chamber investigations characterizing the primary organic aerosol (POA and the corresponding SOA formation at atmospherically relevant concentrations for three in-use diesel vehicles with different exhaust aftertreatment systems. One vehicle lacked exhaust aftertreatment devices, one vehicle was equipped with a diesel oxidation catalyst (DOC and the final vehicle used both a DOC and diesel particulate filter (DPF. The experiments presented here were obtained from the vehicles at conditions representative of idle mode, and for one car in addition at a speed of 60 km/h. An Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS was used to measure the organic aerosol (OA concentration and to obtain information on the chemical composition. For the conditions explored in this paper, primary aerosols from vehicles without a particulate filter consisted mainly of black carbon (BC with a low fraction of organic matter (OM, OM/BC<0.5, while the subsequent aging by photooxidation resulted in a consistent production of SOA only for the vehicles without a DOC and with a deactivated DOC. After 5 h of aging ~80% of the total organic aerosol was on average secondary and the estimated "emission factor" for SOA was 0.23–0.56 g/kg fuel burned. In presence of both a DOC and a DPF, primary particles with a mobility diameter above 5 nm were 300±19 cm−3, and only 0.01 g SOA per kg fuel burned was produced within 5 h after lights on. The mass spectra indicate that POA was mostly a non-oxidized OA with an oxygen to carbon atomic ratio (O

  1. Impact of aftertreatment devices on primary emissions and secondary organic aerosol formation potential from in-use diesel vehicles: results from smog chamber experiments (United States)

    Chirico, R.; Decarlo, P. F.; Heringa, M. F.; Tritscher, T.; Richter, R.; Prévôt, A. S. H.; Dommen, J.; Weingartner, E.; Wehrle, G.; Gysel, M.; Laborde, M.; Baltensperger, U.


    Diesel particulate matter (DPM) is a significant source of aerosol in urban areas and has been linked to adverse health effects. Although newer European directives have introduced increasingly stringent standards for primary PM emissions, gaseous organics emitted from diesel cars can still lead to large amounts of secondary organic aerosol (SOA) in the atmosphere. Here we present results from smog chamber investigations characterizing the primary organic aerosol (POA) and the corresponding SOA formation at atmospherically relevant concentrations for three in-use diesel vehicles with different exhaust aftertreatment systems. One vehicle lacked exhaust aftertreatment devices, one vehicle was equipped with a diesel oxidation catalyst (DOC) and the third vehicle used both a DOC and diesel particulate filter (DPF). The experiments presented here were obtained from the vehicles at conditions representative of idle mode, and for one car in addition at a speed of 60 km/h. An Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) was used to measure the organic aerosol (OA) concentration and to obtain information on the chemical composition. For the conditions explored in this paper, primary aerosols from vehicles without a particulate filter consisted mainly of black carbon (BC) with a low fraction of organic matter (OM, OM/BC < 0.5), while the subsequent aging by photooxidation resulted in a consistent production of SOA only for the vehicles without a DOC and with a deactivated DOC. After 5 h of aging ~80% of the total organic aerosol was on average secondary and the estimated "emission factor" for SOA was 0.23-0.56 g/kg fuel burned. In presence of both a DOC and a DPF, only 0.01 g SOA per kg fuel burned was produced within 5 h after lights on. The mass spectra indicate that POA was mostly a non-oxidized OA with an oxygen to carbon atomic ratio (O/C) ranging from 0.10 to 0.19. Five hours of oxidation led to a more oxidized OA with an O/C range of 0

  2. Potential Prepore Trimer Formation by the Bacillus thuringiensis Mosquito-specific Toxin: MOLECULAR INSIGHTS INTO A CRITICAL PREREQUISITE OF MEMBRANE-BOUND MONOMERS. (United States)

    Sriwimol, Wilaiwan; Aroonkesorn, Aratee; Sakdee, Somsri; Kanchanawarin, Chalermpol; Uchihashi, Takayuki; Ando, Toshio; Angsuthanasombat, Chanan


    The insecticidal feature of the three-domain Cry δ-endotoxins from Bacillus thuringiensis is generally attributed to their capability to form oligomeric pores, causing lysis of target larval midgut cells. However, the molecular description of their oligomerization process has not been clearly defined. Here a stable prepore of the 65-kDa trypsin-activated Cry4Ba mosquito-specific toxin was established through membrane-mimetic environments by forming an ∼200-kDa octyl-β-D-glucoside micelle-induced trimer. The SDS-resistant trimer caused cytolysis to Sf9 insect cells expressing Aedes-mALP (a Cry4Ba receptor) and was more effective than a toxin monomer in membrane perturbation of calcein-loaded liposomes. A three-dimensional model of toxin trimer obtained by negative-stain EM in combination with single-particle reconstruction at ∼5 nm resolution showed a propeller-shaped structure with 3-fold symmetry. Fitting the three-dimensional reconstructed EM map with a 100-ns molecular dynamics-simulated Cry4Ba structure interacting with an octyl-β-D-glucoside micelle showed relative positioning of individual domains in the context of the trimeric complex with a major protrusion from the pore-forming domain. Moreover, high-speed atomic force microscopy imaging at nanometer resolution and a subsecond frame rate demonstrated conformational transitions from a propeller-like to a globularly shaped trimer upon lipid membrane interactions, implying prepore-to-pore conversion. Real-time trimeric arrangement of monomers associated with L-α-dimyristoylphosphatidylcholine/3-[(3-cholamidopropyl)dimethylammonio]-2-hydroxy-1-propanesulfonic acid bicelle membranes was also envisaged by successive high-speed atomic force microscopy imaging, depicting interactions among three individual subunits toward trimer formation. Together, our data provide the first pivotal insights into the structural requirement of membrane-induced conformational changes of Cry4Ba toxin monomers for the

  3. The group I metabotropic glutamate receptor mGluR5 is required for fear memory formation and long-term potentiation in the lateral amygdala. (United States)

    Rodrigues, Sarina M; Bauer, Elizabeth P; Farb, Claudia R; Schafe, Glenn E; LeDoux, Joseph E


    The group I metabotropic glutamate receptor subtype mGluR5 has been shown to play a key role in the modulation of synaptic plasticity. The present experiments examined the function of mGluR5 in the circuitry underlying Pavlovian fear conditioning using neuroanatomical, electrophysiological, and behavioral techniques. First, we show using immunocytochemical and tract-tracing methods that mGluR5 is localized to dendritic shafts and spines in the lateral nucleus of the amygdala (LA) and is postsynaptic to auditory thalamic inputs. In electrophysiological experiments, we show that long-term potentiation at thalamic input synapses to the LA is impaired by bath application of a specific mGluR5 antagonist, 2-methyl-6-(phenyle-thynyl)-pyridine (MPEP), in vitro. Finally, we show that intra-amygdala administration of MPEP dose-dependently impairs the acquisition, but not expression or consolidation, of auditory and contextual fear conditioning. Collectively, the results of this study indicate that mGluR5 in the LA plays a crucial role in fear conditioning and in plasticity at synapses involved in fear conditioning.

  4. Galaxy formation

    CERN Document Server

    Silk, Joseph; Dvorkin, Irina


    Galaxy formation is at the forefront of observation and theory in cosmology. An improved understanding is essential for improving our knowledge both of the cosmological parameters, of the contents of the universe, and of our origins. In these lectures intended for graduate students, galaxy formation theory is reviewed and confronted with recent observational issues. In Lecture 1, the following topics are presented: star formation considerations, including IMF, star formation efficiency and star formation rate, the origin of the galaxy luminosity function, and feedback in dwarf galaxies. In Lecture 2, we describe formation of disks and massive spheroids, including the growth of supermassive black holes, negative feedback in spheroids, the AGN-star formation connection, star formation rates at high redshift and the baryon fraction in galaxies.

  5. Soil formation.

    NARCIS (Netherlands)

    Breemen, van N.; Buurman, P.


    Soil Formation deals with qualitative and quantitative aspects of soil formation (or pedogenesis) and the underlying chemical, biological, and physical processes. The starting point of the text is the process - and not soil classification. Effects of weathering and new formation of minerals, mobilis

  6. Tissue formation and tissue engineering through host cell recruitment or a potential injectable cell-based biocomposite with replicative potential: Molecular mechanisms controlling cellular senescence and the involvement of controlled transient telomerase activation therapies. (United States)

    Babizhayev, Mark A; Yegorov, Yegor E


    . Nuclear export is initiated by ROS-induced phosphorylation of tyrosine 707 within hTERT by the Src kinase family. It might be presumed that protection of mitochondria against oxidative stress is an important telomere length-independent function for telomerase in cell survival. Biotechnology companies are focused on development of therapeutic telomerase vaccines, telomerase inhibitors, and telomerase promoter-driven cell killing in oncology, have a telomerase antagonist in late preclinical studies. Anti-aging medicine-oriented groups have intervened on the market with products working on telomerase activation for a broad range of degenerative diseases in which replicative senescence or telomere dysfunction may play an important role. Since oxidative damage has been shown to shorten telomeres in tissue culture models, the adequate topical, transdermal, or systemic administration of antioxidants (such as, patented ocular administration of 1% N-acetylcarnosine lubricant eye drops in the treatment of cataracts) may be beneficial at preserving telomere lengths and delaying the onset or in treatment of disease in susceptible individuals. Therapeutic strategies toward controlled transient activation of telomerase are targeted to cells and replicative potential in cell-based therapies, tissue engineering and regenerative medicine.

  7. Combination of leader-follower method and potential function about ship formation control%领航跟随法和势函数组合的船舶编队控制

    Institute of Scientific and Technical Information of China (English)

    李芸; 肖英杰


    多船舶作业在海上越来越盛行,最常见的运行方式就是船舶编队协控,本文考虑领航跟随法过于集中控制的不足,将船舶编队分为领航–跟随控制阶段和跟随–跟随控制两个阶段。在第1个阶段使用多输入滑模控制以及船舶响应模型进行控制律分配;第2阶段引入势函数方法,结合图形拓扑来约束跟随船舶间的间距,提高队形的稳固性,弥补单一领航跟随法的不足,并通过Lyapunov函数验证系统控制的稳定性。后期通过直线和曲线路径的仿真验证,得到编队船舶的各状态历时趋势,船舶间状态最终达到一致性,实现队形保持的目标,得出良好效果,验证了算法的有效性。%As multi-vessel operation prevails increasingly at sea, the most common mode is ship formation control. Considering the over-centralized control of leader-follower method, the multi-vessel formation is divided into the leader-follower control stage and follower-follower control stage in this paper. At the first stage, the control law utilizing sliding mode control and ship response model is applied. The potential function method which combines with the graph topology is introduced to constrain the balance distance for follower in the second stage. These methods can improve stability of the formation, to make up for the single leader-follower method. The stability of control system is verified by the Lyapunov function. Finally getting the state diachronic trend of ship formation by the simulation of straight and curve path verification, the ship state achieves consistency, reaching the goal of maintaining the formation, which obtains good results and tests the effectiveness of algorithm.

  8. Acrylamide-forming potential of potatoes grown at different locations, and the ratio of free asparagine to reducing sugars at which free asparagine becomes a limiting factor for acrylamide formation. (United States)

    Muttucumaru, Nira; Powers, Stephen J; Elmore, J Stephen; Dodson, Andrew; Briddon, Adrian; Mottram, Donald S; Halford, Nigel G


    Acrylamide is produced from free asparagine and reducing sugars during high-temperature cooking and food processing, and potato products are major contributors to dietary acrylamide intake. The present study analysed twenty varieties of potatoes grown at two sites (Doncaster and Woburn) in the United Kingdom to assess the effect of location of cultivation on acrylamide-forming potential. Analysis of variance revealed a full site by variety nested within type (French fry, boiling and crisping) by storage interaction for acrylamide (pacrylamide identified a value of 2.257±0.149 as the tipping point in the ratio below which free asparagine concentration could affect acrylamide formation. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. Real Time Monitoring of Dissolved Organic Carbon Concentration and Disinfection By-Product Formation Potential in a Surface Water Treatment Plant with Simulaneous UV-VIS Absorbance and Fluorescence Excitation-Emission Mapping (United States)

    Gilmore, A. M.


    This study describes a method based on simultaneous absorbance and fluorescence excitation-emission mapping for rapidly and accurately monitoring dissolved organic carbon concentration and disinfection by-product formation potential for surface water sourced drinking water treatment. The method enables real-time monitoring of the Dissolved Organic Carbon (DOC), absorbance at 254 nm (UVA), the Specific UV Absorbance (SUVA) as well as the Simulated Distribution System Trihalomethane (THM) Formation Potential (SDS-THMFP) for the source and treated water among other component parameters. The method primarily involves Parallel Factor Analysis (PARAFAC) decomposition of the high and lower molecular weight humic and fulvic organic component concentrations. The DOC calibration method involves calculating a single slope factor (with the intercept fixed at 0 mg/l) by linear regression for the UVA divided by the ratio of the high and low molecular weight component concentrations. This method thus corrects for the changes in the molecular weight component composition as a function of the source water composition and coagulation treatment effects. The SDS-THMFP calibration involves a multiple linear regression of the DOC, organic component ratio, chlorine residual, pH and alkalinity. Both the DOC and SDS-THMFP correlations over a period of 18 months exhibited adjusted correlation coefficients with r2 > 0.969. The parameters can be reported as a function of compliance rules associated with required % removals of DOC (as a function of alkalinity) and predicted maximum contaminant levels (MCL) of THMs. The single instrument method, which is compatible with continuous flow monitoring or grab sampling, provides a rapid (2-3 minute) and precise indicator of drinking water disinfectant treatability without the need for separate UV photometric and DOC meter measurements or independent THM determinations.

  10. Modeling Trihalomethane Formation Potential from Wastewater Chlorination (United States)


    chemically with each other, and with living organisms, particularly bacteria ( Manahan , 1991:435). To ensure effective disinfection, to meet the CWA...halogens are strong oxidants and are highly reactive ( Manahan , 1991:504). Chlorine is never found uncombined in nature, it exists only as the...HOCI) according to the following reaction: Cl2 (gas) + H20 =• HOC1 + H+ + Cl The hydrogen is oxidized and the chlorine gas is reduced ( Manahan , 1991

  11. Effects of in-medium cross-sections and optical potential on thermal-source formation in p+197Au reactions at 6.2-14.6 GeV/c

    CERN Document Server

    Turbide, S; Danielewicz, P; Viola, V E; Roy, R; Kwiatkowski, K; Hsi, W C; Wang, G; Lefort, T; Bracken, D S; Breuer, H; Cornell, E; Gimeno-Nogues, F; Ginger, D S; Gushue, S; Huang, R; Korteling, R; Lynch, W G; Morley, K B; Ramakrishnan, E; Remsberg, L P; Rowland, D; Tsang, M B; Xi, H; Yennello, S J


    Effects of in-medium cross-sections and of optical potential on pre-equilibrium emission and on formation of a thermal source are investigated by comparing the results of transport simulations with experimental results from the p+{197}Au reaction at 6.2-14.6 GeV/c. The employed transport model includes light composite-particle production and allows for inclusion of in-medium particle-particle cross-section reduction and of momentum dependence in the particle optical-potentials. Compared to the past, the model incorporates improved parameterizations of elementary high-energy processes. The simulations indicate that the majority of energy deposition occurs during the first ~25 fm/c of a reaction. This is followed by a pre-equilibrium emission and readjustment of system density and momentum distribution toward an equilibrated system. Good agreement with data, on the d/p and t/p yield ratios and on the residue mass and charge numbers, is obtained at the time of ~ 65 fm/c from the start of a reaction, provided red...

  12. Assessment of hybrid, meta-hybrid-GGA, and long-range corrected density functionals for the estimation of enthalpies of formation, barrier heights, and ionisation potentials of selected C1-C5 oxygenates (United States)

    El-Nahas, Ahmed M.; Simmie, John M.; Mangood, Ahmed H.; Hirao, Kimihiko; Song, Jong-Won; Watson, Mark A.; Taketsugu, Tetsuya; Koga, Nobuaki


    The enthalpies of formation for some selected oxygenates have been calculated by the atomisation energy approach using B3LYP, BHandHLYP, MPW3LYP, MPW1K, MPWB1K, BB1K, MPW1B95, BMK, and long-range corrected (LC-ωPBE, LC-BOP, LCgau-BOP, LC-BOP12, LCgau-B97) density functionals, as well as the composite CBS-QB3 method. Compared with experiment, BMK, LC-ωPBE, LCgau-BOP, LC-BOP12, LCgau-B97, MPW195, MPW3LYP functionals and CBS-QB3 give root mean square errors (RMSE) in enthalpies of formation no greater than 4 kcal/mol, whilst MPW1K and BHandHLYP show much worse performance (RMSE of 20-40 kcal/mol). The B3LYP, MPWB1K, and BB1K results fall between the two extremes. Energy barriers for the dominant paths in the unimolecular decomposition of simple esters (HCO2CH3, C2H5CO2C2H5), C1-C3 acids, and 1-butanol are reproduced well by CBS-QB3, BMK, BB1K, LCgau-B97, and PW1B95 (RMSE = 1-2 kcal/mol), while other LC methods (LC-ωPBE, LC-BOP, LCgau-BOP, and LC-BOP12) show a deviation of up to 4 kcal/mol. For the ionisation potentials, calculated from Koopman's theorem, all of the investigated LC-methods give good results compared with other density functional theory functionals with a maximum deviation of 0.4 eV, except for LCgau-B97, which has an RMSE of 0.7 eV.

  13. Galaxy Formation

    DEFF Research Database (Denmark)

    Sparre, Martin

    Galaxy formation is an enormously complex discipline due to the many physical processes that play a role in shaping galaxies. The objective of this thesis is to study galaxy formation with two different approaches: First, numerical simulations are used to study the structure of dark matter and how...... galaxies form stars throughout the history of the Universe, and secondly it is shown that observations of gamma-ray bursts (GRBs) can be used to probe galaxies with active star formation in the early Universe. A conclusion from the hydrodynamical simulations is that the galaxies from the stateof......-the-art cosmological simulation, Illustris, follow a tight relation between star formation rate and stellar mass. This relation agrees well with the observed relation at a redshift of z = 0 and z = 4, but at intermediate redshifts of z ' 2 the normalisation is lower than in real observations. This is highlighted...

  14. 水中典型含氮有机物氯化生成消毒副产物的潜能研究%Chlorination Byproducts Formation Potentials of Typical Nitrogenous Organic Compounds in Water

    Institute of Scientific and Technical Information of China (English)

    徐倩; 徐斌; 覃操; 夏圣骥; 高乃云; 田富箱; 李大鹏


    选取了受污染原水中广泛存在的12种含氮有机物(除草剂、杀虫剂、氨基酸、工业品等),开展了氯化和氯胺化培养生成典型消毒副产物的实验,目的是通过对水中脲类除草剂、嗪类除草剂和其他含氮化合物培养生成不同消毒副产物的生成量,讨论不同种类含氮化合物生成含碳和含氮消毒副产物规律以及考察不同消毒副产物的可能前体物.研究发现,脲类除草剂经过量氯化和氯胺化可产生多达9种消毒副产物,反应活性最高的绿麦隆可生成三氯甲烷(CF)、一氯乙酸(MCAA)、二氯乙酸(DCAA)、1,1-二氯丙酮(1,1-DCP)、1,1,1-三氯丙酮%Twelve typical nitrogenous organic compounds including herbicides,pesticides,amino acids,industrial products etc in polluted raw water were selected to investigate formation of typical carbonaceous and nitrogenous DBPs during chlorination and chloramination.To indentify the formation mechanism of carbonaceous and nitrogenous disinfection byproducts from nitrogenous chemicals,chlorination and chloroamination of urea herbicides,triazine herbicides,amino acid,and other compounds were investigated.As a result,the potential precursors for different DBPs were defined as well.It has been identified that widely used urea herbicides could produce as many as 9 specific DBPs.The chlorotoluron shows highest reactivity and yields chloroform(CF),monochloroacetic acid(MCAA),dichloroacetic acid(DCAA),1,1-dichloro-acetone(1,1-DCP),1,1,1-trichloro-acetone(1,1,1-TCP),chloropicrin(NTCM),dichloro-acetonitrile(DCAN),dimethylnitrosamine(NDMA).The results indicated that aldicarb and dinoseb are important precursors of CF,DCAA,MCAA,NTCM as well.High concentrations of CF and DCAA were found during L-tryptophan chlorination.Furthermore,DBPs formation pathways and mechanisms were suggested during chlorination and chloramination of chlorotoluron,ametryn,dinoseb L-tryptophan.

  15. Geology of tight oil and potential tight oil reservoirs in the lower part of the Green River Formation, Uinta, Piceance, and Greater Green River Basins, Utah, Colorado, and Wyoming (United States)

    Johnson, Ronald C.; Birdwell, Justin E.; Mercier, Tracey J.; Brownfield, Michael E.


    The recent successful development of a tight oil play in the Eocene-age informal Uteland Butte member of the lacustrine Green River Formation in the Uinta Basin, Utah, using modern horizontal drilling and hydraulic fracturing techniques has spurred a renewed interest in the tight oil potential of lacustrine rocks. The Green River Formation was deposited by two large lakes, Lake Uinta in the Uinta and Piceance Basins and Lake Gosiute in the Greater Green River Basin. These three basins contain the world’s largest in-place oil shale resources with recent estimates of 1.53 trillion, 1.33 trillion, and 1.44 trillion barrels of oil in place in the Piceance, Uinta, and Greater Green River Basins, respectively. The Uteland Butte member was deposited during an early freshwater stage of the lake in the Uinta Basin prior to deposition of the assessed oil shale intervals. This report only presents information on the early freshwater interval and overlying brackish-water interval in all three basins because these intervals are most likely to have tight oil potential. Burial histories of the three basins were reconstructed to study (1) variations in subsidence and lake development, and (2) post deposition burial that led to the development of a petroleum system in only the Uinta Basin. The Uteland Butte member is a successful tight oil play because it is thermally mature for hydrocarbon generation and contains organic-rich shale, brittle carbonate, and porous dolomite. Abnormally high pressure in parts of the Uteland Butte is also important to production. Variations in organic richness of the Uteland Butte were studied using Fischer assay analysis from oil shale assessments, and pressures were studied using drill-stem tests. Freshwater lacustrine intervals in the Piceance and Greater Green River Basins are immature for hydrocarbon generation and contain much less carbonate than the Uteland Butte member. The brackish-water interval in the Uinta Basin is thermally mature for

  16. Solvent assisted formation of ruthenium(III) and ruthenium(II) hydrazone complexes in one-pot with potential in vitro cytotoxicity and enhanced LDH, NO and ROS release. (United States)

    Jayanthi, Eswaran; Kalaiselvi, Sivalingam; Padma, Viswanatha Vijaya; Bhuvanesh, Nattamai S P; Dharmaraj, Nallasamy


    A set each of new bivalent and trivalent ruthenium complexes, [Ru(III)(HL)Cl2(EPh3)2] and [Ru(II)(L)(CO)(EPh3)2] (E = P (complexes and ) or As (complexes and )) were synthesised from the reactions of [Ru(III)Cl3(EPh3)3] with 2-hydroxynaphthaldehyde benzoic acid hydrazone (H2L) in methanol-chloroform and characterized by elemental analysis, spectral data and XRD study. A suitable mechanism to account for the formation of bivalent ruthenium carbonyl complexes from the corresponding trivalent precursors is provided by considering the role of added base in the reaction. Interaction of complexes with CT-DNA/bovine serum albumin was analysed with absorption and emission spectral titration studies. In vitro cytotoxic potential of the above ruthenium hydrazone complexes assayed against the A549 cell line revealed a significant growth inhibition. The test complexes added in IC50 concentration into the cell culture medium enhanced the release of lactate dehydrogenase, NO and reactive oxygen species in comparison with the control. Cell death induced by the complexes was studied using a propidium iodide staining assay and showed noticeable changes in the cell morphology which resembled apoptosis.

  17. Galaxy Formation

    DEFF Research Database (Denmark)

    Sparre, Martin

    galaxies form stars throughout the history of the Universe, and secondly it is shown that observations of gamma-ray bursts (GRBs) can be used to probe galaxies with active star formation in the early Universe. A conclusion from the hydrodynamical simulations is that the galaxies from the stateof......-the-art cosmological simulation, Illustris, follow a tight relation between star formation rate and stellar mass. This relation agrees well with the observed relation at a redshift of z = 0 and z = 4, but at intermediate redshifts of z ' 2 the normalisation is lower than in real observations. This is highlighted...... of GRB host galaxies is affected by the fact that GRBs appear mainly to happen in low-metallicity galaxies. Solving this problem will make it possible to derive the total cosmic star formation rate more reliably from number counts of GRBs....

  18. Hippocampal formation

    NARCIS (Netherlands)

    Cappaert, N.L.M.; van Strien, N.M.; Witter, M.P.; Paxinos, G.


    The hippocampal formation and parahippocampal region are prominent components of the rat nervous system and play a crucial role in learning, memory, and spatial navigation. Many new details regarding the entorhinal cortex have been discovered since the previous edition, and the growing interest in t

  19. Potential Assessment on Shale Gas in Lower Napo Formation of Oriente Basin, Ecuador%厄瓜多尔奥连特盆地下Napo组页岩气资源潜力评价

    Institute of Scientific and Technical Information of China (English)



    针对厄瓜多尔富油贫气的现状, 评价其主要含油气盆地——奥连特盆地页岩气勘探潜力. 给出了页岩气储层标准, 通过对奥连特盆地岩性、 地球化学指标、 深度、 分布稳定性及资料完善程度诸方面综合分析, 优选出下Napo组页岩作为具有页岩气勘探潜力的地层. 并研究其成藏条件, 利用不同区块38口井测井解释成果, 获得页岩厚度分布及变化趋势, 通过29条地震测线解释成果, 研究了下Napo组页岩在盆地内的变化趋势, 综合前人研究成果及地球化学指标, 预测了盆地下Napo组页岩气勘探有利区. 结果表明, 盆地的东部地区 ( 12区块、 67区块、 18区块、 31区块及 63区块) 和西北地区 ( 11区块、 18区块) 对页岩气勘探开发相对有利, 其次是西部地区 ( 29区块、 20区块、 22区块、 28区块、 70区块) , 研究成果为厄瓜多尔奥连特盆地页岩气勘探指明了方向.%For more petroleum and less gas in Ecuador, we assessed the shale gas exploration potential of its main oil and gas bearing basin, Oriente Basin. We gave the shale gas reservoir criteria, and analyzed lithology, geochemical factors, depth, distribution stability, and data perfection, and chose the shale in lower Napo Formation in the Basin as promising. We probed into its reservoir forming conditions, used the logging interpretation results of 38 wells in different blocks and obtained shale thickness distribution and variation trend. Through the interpretation results of 29 seismic lines, we studied the variation of the shale in lower Napo Formation in the Basin, and utilized previous research results and geochemical fac-tors to predict the favorable areas for shale gas exploration in lower Napo Formation. Results showed that the eastern areas ( Block 12, Block 67, Block 18, Block 31 and Block 63) and the northwestern area ( Block 11 and Block 18) were more favorable for shale gas exploration and development

  20. Analysis of Tank 13H (HTF-13-14-156, 157) Surface and Subsurface Supernatant Samples in Support of Enrichment Control, Corrosion Control and Sodium Aluminosilicate Formation Potential Programs

    Energy Technology Data Exchange (ETDEWEB)

    Oji, L. N. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL). Advanced Characterization and Processing


    The 2H Evaporator system includes mainly Tank 43H (feed tank) and Tank 38H (drop tank) with Tank 22H acting as the DWPF recycle receipt tank. The Tank 13H is being characterized to ensure that it can be transferred to the 2H evaporator. This report provides the results of analyses on Tanks 13H surface and subsurface supernatant liquid samples to ensure compliance with the Enrichment Control Program (ECP), the Corrosion Control Program and Sodium Aluminosilicate Formation Potential in the Evaporator. The U-235 mass divided by the total uranium averaged 0.00799 (0.799 % uranium enrichment) for both the surface and subsurface Tank 13H samples. This enrichment is slightly above the enrichment for Tanks 38H and 43H, where the enrichment normally ranges from 0.59 to 0.7 wt%. The U-235 concentration in Tank 13H samples ranged from 2.01E-02 to 2.63E-02 mg/L, while the U-238 concentration in Tank 13H ranged from 2.47E+00 to 3.21E+00 mg/L. Thus, the U-235/total uranium ratio is in line with the prior 2H-evaporator ECP samples. Measured sodium and silicon concentrations averaged, respectively, 2.46 M and 1.42E-04 M (3.98 mg/L) in the Tank 13H subsurface sample. The measured aluminum concentration in Tanks 13H subsurface samples averaged 2.01E-01 M.

  1. DNA oxidation as a potential molecular mechanism mediating drug-induced birth defects: phenytoin and structurally related teratogens initiate the formation of 8-hydroxy-2'-deoxyguanosine in vitro and in vivo in murine maternal hepatic and embryonic tissues. (United States)

    Liu, L; Wells, P G


    A considerable number of teratogens, including the anticonvulsant drug phenytoin and structurally related drugs and environmental chemicals, may be bioactivated by peroxidases, such as prostaglandin H synthase (PHS) and lipoxygenases (LPOs), to a reactive free radical intermediate that initiates birth defects. However, the molecular targets of the reactive free radical intermediates mediating chemical teratogenesis, and hence the fundamental determinants of susceptibility, are poorly understood. In these studies, a teratogenic dose of phenytoin (65 mg/kg), when injected into pregnant CD-1 mice during organogenesis on gestational day 12, initiated the oxidation of DNA in maternal hepatic and embryonic nuclei, forming 8-hydroxy-2'-deoxyguanosine. Significant maternal and embryonic DNA oxidation occurred at 6 and 3 h, respectively, suggesting relative embryonic deficiencies in free radical-related cytoprotective enzymes, although the rates appeared similar. Maximal DNA oxidation in both maternal and embryonic tissues occurred at 6 h, presumably reflecting the balance of DNA oxidation and repair, the latter of which appeared similar in both tissues. Inhibition of phenytoin-initiated embryonic DNA oxidation by the free radical spin trapping agent alpha-phenyl-N-t-butylnitrone (41.5 mg/kg), and by acetylsalicylic acid (10 mg/kg), an inhibitor of the cyclooxygenase component of PHS, was consistent with the previously reported reduction by these inhibitors of phenytoin-initiated murine birth defects. In vitro studies using a horseradish peroxidase (0.5 mg/ml)-H2O2 (5.45 micrograms/ml) bioactivating system for drug-initiated oxidation of 2'-deoxyguanosine (3.74 mM), indicated that the potency of xenobiotic-initiated formation of 8-hydroxy-2'-deoxyguanosine for the structurally related drugs and metabolites phenytoin, 5-(p-hydroxyphenyl)-5-phenylhydantoin, trimethadione, dimethadione, l-mephenytoin, l-nirvanol, d-nirvanol (80 microM each), or thalidomide (64 micro

  2. Galaxy formation. (United States)

    Peebles, P J


    It is argued that within the standard Big Bang cosmological model the bulk of the mass of the luminous parts of the large galaxies likely had been assembled by redshift z approximately 10. Galaxy assembly this early would be difficult to fit in the widely discussed adiabatic cold dark matter model for structure formation, but it could agree with an isocurvature version in which the cold dark matter is the remnant of a massive scalar field frozen (or squeezed) from quantum fluctuations during inflation. The squeezed field fluctuations would be Gaussian with zero mean, and the distribution of the field mass therefore would be the square of a random Gaussian process. This offers a possibly interesting new direction for the numerical exploration of models for cosmic structure formation.

  3. Cloud Formation (United States)

    Graham, Mark Talmage


    Cloud formation is crucial to the heritage of modern physics, and there is a rich literature on this important topic. In 1927, Charles T.R. Wilson was awarded the Nobel Prize in physics for applications of the cloud chamber.2 Wilson was inspired to study cloud formation after working at a meteorological observatory on top of the highest mountain in Scotland, Ben Nevis, and testified near the end of his life, "The whole of my scientific work undoubtedly developed from the experiments I was led to make by what I saw during my fortnight on Ben Nevis in September 1894."3 To form clouds, Wilson used the sudden expansion of humid air.4 Any structure the cloud may have is spoiled by turbulence in the sudden expansion, but in 1912 Wilson got ion tracks to show up by using strobe photography of the chamber immediately upon expansion.5 In the interim, Millikan's study in 1909 of the formation of cloud droplets around individual ions was the first in which the electron charge was isolated. This study led to his famous oil drop experiment.6 To Millikan, as to Wilson, meteorology and physics were professionally indistinct. With his meteorological physics expertise, in WWI Millikan commanded perhaps the first meteorological observation and forecasting team essential to military operation in history.7 But even during peacetime meteorology is so much of a concern to everyone that a regular news segment is dedicated to it. Weather is the universal conversation topic, and life on land could not exist as we know it without clouds. One wonders then, why cloud formation is never covered in physics texts.

  4. Cement Formation

    DEFF Research Database (Denmark)

    Telschow, Samira; Jappe Frandsen, Flemming; Theisen, Kirsten


    Cement production has been subject to several technological changes, each of which requires detailed knowledge about the high multiplicity of processes, especially the high temperature process involved in the rotary kiln. This article gives an introduction to the topic of cement, including...... an overview of cement production, selected cement properties, and clinker phase relations. An extended summary of laboratory-scale investigations on clinkerization reactions, the most important reactions in cement production, is provided. Clinker formations by solid state reactions, solid−liquid and liquid...

  5. 铜离子催化DPKA关环反应及其潜在应用%Cu Ⅱ-induced Ring-formation Reaction of Di-pyridylketone Azine and Its Potential Application

    Institute of Scientific and Technical Information of China (English)

    吴大雨; 黄薇; 闫文波; 段春迎; 谢黎霞; 孟庆金


    铜离子催化的氧化关环有机反应,用于选择性荧光探测金属铜离子的存在.晶体结构和光谱分析表明,在DPKA的乙腈/水混合溶剂中,引入铜离子可以促使苯并三氮唑类荧光化合物(2)的形成,该反应可以使得溶液的荧光明显增强.而且在滴定溶液里,引入Cu2+螯合剂EDTA,并不能使得溶液的荧光减弱,表明荧光是由有机物2发射的.同时,其他金属离子的引入并不能产生荧光,而且干扰离子的存在也不能使得荧光光谱发生显著改变,表明DPKA可以高选择性的检测溶液中的铜离子.研究表明,荧光响应呈现2个线性关系,区间分别在0.64~3.2 mg·kg-1和3.84~7.04 mg·kg-1.%A Cu-promoted ring-closed reaction of di-pyridylketone azine (DPKA) was developed in the design of a fluorescent chemodosimeter for potential selective Cu (Ⅱ)detection. Structure and spectroscopic investigations demonstrated the formation of a 3H-pyrazolo[4,3-b]pyridine (2) and the "turn-on" response for Cu(Ⅱ) in aqueous acetonitrile media. The introduction of Cu2+ chelator, such as EDTA, into the titration solution will not weaken the fluorescence, indicating the fluorescence is emitted from the organic compound (2). Two independent linear correlations exist in the range of 0.64~3.2mg·kg-1 and 3.84~7.04mg·kg-1,respectively.

  6. 锌缺乏对小鼠海马长时程增强的影响%Effect of Zinc deficiency on the formation of hippocampal long term potentiation

    Institute of Scientific and Technical Information of China (English)

    王佐周; 高慧玲; 徐赫; 王涛; 王占友


    Objective To investigate the effect of zinc deficiency on hippocampal zinc content and long term potentiation (LTP) in the mouse. Methods CD-1 mice at 3 weeks of age were fed with zinc-deficient diet (O.85mg/kg) for 5 weeks. Autometallography (AMG) was carried out to analyze the zinc content in the hippocampus. A concentric bipolar stimulating electrode was placed in the orientation of the mossy fiber lamellae of the fight dentate gyrus (DG) and a glass capillary recording electrode was placed ipsilaterally in the stratum pyramidal of the CA3 region of the hippecampus. LTP was evoked by a train of high frequency stimulations (HFS), and the changes of population spike (PS) and field excitatory postsynapfic potential (f-EPSP) were recorded, in order to analyze the effect of LTP under zinc deficiency. Results AMG staining showed that treatment with zinc-deficient diet reduced the level of zinc in hippocampal CA1, CA3 and dentate gyrus (p<0.05-0.O1). Electrophysiological in vivo recordings showed that zinc deficiency resulted in impairments of mossy fiber LTP (p<O.01). Conclusion Zinc deficiency results in a decreased level of free zinc ions in the hippocampus, which is associated with the inhibition of the formation of LTP.%目的 探讨锌缺乏对小鼠海马区域锌离子含量以及长时程增强(LTP)的影响.方法 3周龄CD-1小鼠饲以低锌饲料(0.85mg/kg)和去离子水5周进行实验.应用金属自显影技术(AMG)检测低锌饲料喂养对小鼠海马游离锌离子含量的影响;在小鼠海马齿状回的苔藓纤维层插入刺激电极,在CA3区锥体细胞层插入记录电极,记录高频刺激后海马苔藓纤维CA3区引起的峰电位(PS)和兴奋性突触后电位(f-EPSP)的变化,分析锌缺乏对小鼠海马LTP形成的影响.结果 AMG结果显示锌缺乏小鼠海马CA1,CA3和齿状回区域的锌离子含量明显降低(P<0.05-0.01);电生理检测结果表明锌缺乏小鼠在高频刺激后海马苔藓纤

  7. Galaxy Formation

    CERN Document Server

    Longair, Malcolm S


    This second edition of Galaxy Formation is an up-to-date text on astrophysical cosmology, expounding the structure of the classical cosmological models from a contemporary viewpoint. This forms the background to a detailed study of the origin of structure and galaxies in the Universe. The derivations of many of the most important results are derived by simple physical arguments which illuminate the results of more advanced treatments. A very wide range of observational data is brought to bear upon these problems, including the most recent results from WMAP, the Hubble Space Telescope, galaxy surveys like the Sloan Digital Sky Survey and the 2dF Galaxy Redshift Survey, studies of Type 1a supernovae, and many other observations.

  8. Reservoir Characterization for CO2 Sequestration: Assessing the Potential of the Devonian Carbonate Nisku Formation of Central Alberta Caractérisation de réservoir en vue du stockage géologique de CO2 : évaluation du potentiel offert par les carbonates dévoniens de la formation de Nisku, en Alberta central

    Directory of Open Access Journals (Sweden)

    Eisinger C.


    Full Text Available The Wabamun Lake area of Central Alberta, Canada includes several large CO2 point source emitters, collectively producing more than 30 Mt annually. Previous studies established that deep saline aquifers beneath the Wabamun Lake area have good potential for the large-scale injection and storage of CO2. This study reports on the characterization of the Devonian carbonate Nisku Formation for evaluation as a CO2 repository. Major challenges for characterization included sparse well and seismic data, poor quality flow tests, and few modern measurements. Wireline porosity measurements were present in only one-third of the wells, so porosity and flow capacity (permeability-thickness were estimated using wireline electrical measurements. The Archie cementation factor appears to vary between 2 and 3, creating uncertainty when predicting porosity using the electrical measurements; however, high-porosity zones could be identified. The electrically-based flow capacity predictions showed more favorable values using a correlation with core than the relation based on drill stem and production tests. This behavior is expected, since the flow test flow capacities are less influenced by local occurrences of very permeable vuggy and moldic rocks. Facies distributions were modeled using both pixel and object methods. The object models, using dimensions obtained from satellite imaging of modern day environments, gave results that were more consistent with the geological understanding of the Nisku and showed greater large-scale connectivity than the pixel model. Predicted volumes show considerable storage capacity in the Nisku, but flow simulations suggest injection capacities are below an initial 20 Mt/year target using vertical wells. More elaborate well designs, including fracture stimulation or multi-lateral wells may allow this goal to be reached or surpassed. Plusieurs gros émetteurs de CO2, totalisant 30 Mt annuels, sont localisés dans la région du Lac

  9. Pre injection characterisation and evaluation of CO{sub 2} sequestration potential in the Haizume formation, Niigata basin, Japan; Caracterisation avant injection et evaluation du potentiel de sequestration de CO{sub 2} dans la formation de Haizume, bassin de Niigata, Japon. Modelisation geochimique des interactions eau-mineraux-CO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Zwingmann, N. [CSIRO Petroleum, ARRC, Bentley, WA (Australia); Mito, S.; Sorai, M.; Ohsumi, T. [RITE, Kyoto (Japan); Zwingmann, N. [Western, Univ. (Australia); Sorai, M. [Mitsubishi Research Institute, Inc. (Japan)


    The Research Institute of Innovative Technology for the Earth (RITE) is carrying out a small-scale CO{sub 2} injection field experiment to investigate the feasibility of geological sequestration of CO{sub 2} greenhouse gas in the south-west of Nagaoka City, Niigata Prefecture, Japan. Prior to the injection geochemical reactions caused by CO{sub 2} injections were investigated using the geochemical modelling code (EQ3/6). The injection formation is the sedimentary marine Haizume Formation (Pleistocene) in the Uonuma Group, which is covered by a mud-stone seal. The formation is mainly composed of quartz, plagioclase, feldspar, pyroxene, and clays (smectite, chlorite). The sandstone shows minor consolidation and grain size is medium to coarse sand. The total dissolved solid (TDS) of the formation water is approximately 6100 mg/l and the water contains a high Ca{sup 2+} ({>=} 20% of Na{sup +} concentration). The geochemical model was used for an initial adjustment of the formation water chemistry to the formation conditions and a modelling of the formation water-mineral-CO{sub 2} reactions. The modelling results showed a high reactivity of the minerals in the CO{sub 2} rich environment and high mineral conversion rate within the formation. At the final state, approximately 23 mol of CO{sub 2} were taken into 1 kg of formation water and more than 90% of this was stored within carbonate minerals. In this simulation, some uncertainty is associated with the time scale and a more detailed investigation is planned and will address accurate evaluation. (authors)

  10. Pattern Formation (United States)

    Hoyle, Rebecca


    From the stripes of a zebra and the spots on a leopard's back to the ripples on a sandy beach or desert dune, regular patterns arise everywhere in nature. The appearance and evolution of these phenomena has been a focus of recent research activity across several disciplines. This book provides an introduction to the range of mathematical theory and methods used to analyse and explain these often intricate and beautiful patterns. Bringing together several different approaches, from group theoretic methods to envelope equations and theory of patterns in large-aspect ratio-systems, the book also provides insight behind the selection of one pattern over another. Suitable as an upper-undergraduate textbook for mathematics students or as a fascinating, engaging, and fully illustrated resource for readers in physics and biology, Rebecca Hoyle's book, using a non-partisan approach, unifies a range of techniques used by active researchers in this growing field. Accessible description of the mathematical theory behind fascinating pattern formation in areas such as biology, physics and materials science Collects recent research for the first time in an upper level textbook Features a number of exercises - with solutions online - and worked examples

  11. Pollution Characteristics and Ozone Formation Potential of Ambient VOCs in Winter and Spring in Xiamen%厦门冬春季大气VOCs的污染特征及臭氧生成潜势

    Institute of Scientific and Technical Information of China (English)

    徐慧; 张晗; 邢振雨; 邓君俊


    Air samples were collected at urban and rural sites in Xiamen from January to April 2014. The concentrations of 48 ambient volatile organic compounds( VOC) species were measured by the method of cryogenic pre-concentrator and gas chromatography-mass spectrometry(GC/MS). The ozone formation potential(OFP) of VOCs was also calculated with the method of maximum incremental reactivity( MIR) . The results showed that the average mixing ratios of VOCs in winter were 11. 13 × 10 -9 and 7. 17 × 10 -9 at urban and rural sites, respectively, and those in spring were 24. 88 × 10 -9 and 11. 27 × 10 -9 at urban and rural sites, respectively. At both sites, alkanes contributed the most to VOCs, followed by aromatics and alkenes. The ratios of B/T showed that vehicle and solvent evaporation were the main sources of VOCs at urban site. While at rural site, transport of anthropogenic sources was another important source of VOCs besides local biomass emissions. Ten main components including propene, n-butane, i-butane, n-pentane, i-pentane, n-hexane, benzene, toluene, ethylbenzene and m/p-xylene accounted for 61. 57% and 45. 83% of total VOCs at urban and rural sites in winter, respectively, and 62. 83% and 53. 74% at urban and rural sites in spring, respectively. Aromatics contributed the most to total OFP, followed by alkenes. Alkanes contributed the least to OFP with the highest concentration. C3 , C4 alkenes and aromatics were found to be the more reactive species with relatively high contributions to ozone formation in Xiamen. Comparing the average MIR of VOCs at the two sites, it was found that the reactivity of VOCs at rural site was higher than that at urban site.%2014年1~4月在厦门市城区和郊区开展冬春季节大气样品的采集,采用大气预浓缩系统与GC/MS联用技术定量了48种大气挥发性有机物( VOCs),对比分析了冬春季城区和郊区大气VOCs的污染特征,并利用最大增量反应活性( MIR)估算

  12. Isolating Triggered Star Formation

    Energy Technology Data Exchange (ETDEWEB)

    Barton, Elizabeth J.; Arnold, Jacob A.; /UC, Irvine; Zentner, Andrew R.; /KICP, Chicago /Chicago U., EFI; Bullock, James S.; /UC, Irvine; Wechsler, Risa H.; /KIPAC, Menlo


    Galaxy pairs provide a potentially powerful means of studying triggered star formation from galaxy interactions. We use a large cosmological N-body simulation coupled with a well-tested semi-analytic substructure model to demonstrate that the majority of galaxies in close pairs reside within cluster or group-size halos and therefore represent a biased population, poorly suited for direct comparison to 'field' galaxies. Thus, the frequent observation that some types of galaxies in pairs have redder colors than 'field' galaxies is primarily a selection effect. We use our simulations to devise a means to select galaxy pairs that are isolated in their dark matter halos with respect to other massive subhalos (N= 2 halos) and to select a control sample of isolated galaxies (N= 1 halos) for comparison. We then apply these selection criteria to a volume-limited subset of the 2dF Galaxy Redshift Survey with M{sub B,j} {le} -19 and obtain the first clean measure of the typical fraction of galaxies affected by triggered star formation and the average elevation in the star formation rate. We find that 24% (30.5 %) of these L* and sub-L* galaxies in isolated 50 (30) h{sup -1} kpc pairs exhibit star formation that is boosted by a factor of {approx}> 5 above their average past value, while only 10% of isolated galaxies in the control sample show this level of enhancement. Thus, 14% (20 %) of the galaxies in these close pairs show clear triggered star formation. Our orbit models suggest that 12% (16%) of 50 (30) h{sup -1} kpc close pairs that are isolated according to our definition have had a close ({le} 30 h{sup -1} kpc) pass within the last Gyr. Thus, the data are broadly consistent with a scenario in which most or all close passes of isolated pairs result in triggered star formation. The isolation criteria we develop provide a means to constrain star formation and feedback prescriptions in hydrodynamic simulations and a very general method of understanding

  13. Formation depths of Fraunhofer lines

    CERN Document Server

    Gurtovenko, E A


    We have summed up our investigations performed in 1970--1993. The main task of this paper is clearly to show processes of formation of spectral lines as well as their distinction by validity and by location. For 503 photospheric lines of various chemical elements in the wavelength range 300--1000 nm we list in Table the average formation depths of the line depression and the line emission for the line centre and on the half-width of the line, the average formation depths of the continuum emission as well as the effective widths of the layer of the line depression formation. Dependence of average depths of line depression formation on excitation potential, equivalent widths, and central line depth are demonstrated by iron lines.

  14. Dawsonite cement in the Triassic Lam Formation, Shabwa Basin, Yemen: A natural analogue for a potential mineral product of subsurface CO{sub 2} storage for greenhouse gas reduction

    Energy Technology Data Exchange (ETDEWEB)

    Worden, Richard H. [Department of Earth and Ocean Sciences, University of Liverpool, Brownlow Street, Liverpool L69 3GP (United Kingdom)


    The origin and permeability effects of carbonate cement, blamed for poor reservoir quality in the Upper Triassic turbidite sandstones of the Lam Formation in Yemen, have been investigated using petrography, X-ray diffraction, stable isotopes, fluid inclusions and thermodynamic modelling. In order of growth in the sandstone, the carbonate cements include ferroan calcite, dawsonite (NaAlCO{sub 3}(OH){sub 2}), ferroan dolomite and siderite. Ferroan dolomite is the most abundant cement. There is an inverse correlation between permeability and total carbonate cement volume supporting the earlier assertion that carbonate cements are the main control on reservoir quality in these sandstones. Ferroan calcite replaced, and was sourced by, marine limestone rock fragments that are abundant in the turbidite sandstone. The later cements were probably also at least partly sourced from the marine limestone rock fragments. Stable isotope data from ferroan calcite, ferroan dolomite and siderite show that diagenesis occurred in formation water with oxygen isotopes typical of closed-system diagenesis and that only minor organic-derived carbon dioxide was involved in diagenesis. Dawsonite, while not common as a diagenetic mineral in sandstones, has recently been suspected of being a routine consequence of CO{sub 2} storage in the subsurface for greenhouse gas reduction. In the Lam Formation, dawsonite, found at concentrations of up to 8vol% of the rock, grew at the expense of detrital feldspar minerals under conditions of elevated partial pressure of carbon dioxide. Isotopic data show that dawsonite grew in the presence of carbon dioxide with a {delta}{sup 13}C value of about -4 to -2%%. This is distinctly different from the carbon isotope ratio of the gas phase carbon dioxide now present in the sandstone (-27%%), which had an organic source rock origin. The dawsonite {delta}{sup 13}C data probably represent a mixture between carbonate from detrital marine limestone rock fragments and

  15. Improvement in the diagnostic potential of (32)P-postlabeling analysis demonstrated by the selective formation and comparative analysis of nitrated-PAH-derived adducts arising from diesel-particle extracts

    Energy Technology Data Exchange (ETDEWEB)

    Gallagher, J.E.; Kohan, M.J.; George, M.H.; Lewtas, J.


    Studies suggest that DNA adducts derived from N-substituted aryl-compounds are poorly recovered in the nuclease P1 version of the (32)P-postlabeling assay but not the butanol extraction version. Both versions were employed to ascertain whether the differences in sensitivity could be used to select for nitroaromatic-DNA adducts derived by treating calf thymus DNA with organic extracts from four diesel and one gasoline vehicle emission particles. The authors' enhanced the formation of nitrated-PAH-derived adducts through xanthine oxidase-catalyzed nitroreduction of nitrated-polycyclic aromatic hydrocarbons; constituents previously detected in the diesel emissions. All four diesel organic extracts treated with xanthine oxidase resulted in the formation of one major DNA adduct chromatographically distinct from the multiple DNA adducts detected in the rat liver S9-treated incubations. The adduct was detectable with the butanol extraction but not the nuclease P1 version of the (32)P-postlabeling assay and was chromatographically similar to DNA adducts formed following xanthine oxidase nitroreduction of 1-nitropyrene or ascorbic acid treatment of 1-nitro-8-nitrosopyrene and 1-nitro-6-nitrosopyrene.

  16. Development of resazurin-based assay in 384-well format for high throughput whole cell screening of Trypanosoma brucei rhodesiense strain STIB 900 for the identification of potential anti-trypanosomal agents. (United States)

    Lim, Kah Tee; Zahari, Zuriati; Amanah, Azimah; Zainuddin, Zafarina; Adenan, Mohd Ilham


    To accelerate the discovery of novel leads for the treatment of Human African Trypanosomiasis (HAT), it is necessary to have a simple, robust and cost-effective assay to identify positive hits by high throughput whole cell screening. Most of the fluorescence assay was made in black plate however in this study the HTS assay developed in 384-well format using clear plate and black plate, for comparison. The HTS assay developed is simple, sensitive, reliable and reproducible in both types of plates. Assay robustness and reproducibility were determined under the optimized conditions in 384-well plate was well tolerated in the HTS assay, including percentage of coefficient of variation (% CV) of 4.68% and 4.74% in clear and black 384-well plate, signal-to-background ratio (S/B) of 12.75 in clear 384-well plate and 12.07 in black 384-well plate, Z' factor of 0.79 and 0.82 in clear 384-well plate and black 384-well plate, respectively and final concentration of 0.30% dimethylsulfoxide (DMSO) in both types of plate. Drug sensitivity was found to be comparable to the reported anti-trypanosomal assay in 96-well format. The reproducibility and sensitivity of this assay make it compliant to automated liquid handler use in HTS applications.

  17. Pilot-scale UV/H2O2 advanced oxidation process for surface water treatment and downstream biological treatment: effects on natural organic matter characteristics and DBP formation potential. (United States)

    Sarathya, Siva R; Stefan, Mihaela I; Royce, Alan; Mohseni, M


    The effects of the advanced oxidation process (AOP) of ultraviolet radiation in combination with hydrogen peroxide (UV/H2O2) on the structure and biodegradability of dissolved natural organic matter (NOM) and on the formation of disinfection by-products (DBPs) through the post-UV/H2O2 chlorination were investigated using UV reactors equipped with either low-pressure amalgam lamps or medium-pressure mercury vapour lamps. With electrical energy doses and H2O2 concentrations typically applied in full-scale UV systems for water remediation, the UV/H2O2 AOP partially oxidized NOM, reducing its degree of aromaticity and leading to an increase in the level of biodegradable species. Also, when combined with a downstream biological activated carbon (BAC) filter, UV/H2O2 AOP reduced the formation of DBPs by up to 60% for trihalomethanes and 75% for haloacetic acids. Biological activated carbon was also shown to effectively remove biodegradable by-products and residual H2O2.


    Directory of Open Access Journals (Sweden)

    Nediljka Gaurina-Međimurec


    Full Text Available Formate-based fluids has been successfully used in over hunders HPHT well operations since they introduced in field practice. They have many advantages when compared with conventional HPHT drilling and completion fluids such as: minimal formation damage, maintenance of additve properties at high temperatures, reduced hydraulic flow resistance, low potential for differential sticking, naturally lubricating, very low corrosion rates, biodegradable and pose little risk to the environment etc. Formate-based fluids can be applied during deep slim hole drilling, shale drilling, reservoir drilling, salt and gas hydrate formations drilling. The laboratory research was carried out to evaluate the rheological behavior of formate-based fluids as a function of temperature. Formate-based fluids were formulated using potassium formate brine, xanthan polymer, PAC, starch and calcium carbonate. Experimental results show that potassium formate improves the thermal stability of polymers.

  19. Developmental expression profiles of axon guidance signaling and the immune system in the marmoset cortex: potential molecular mechanisms of pruning of dendritic spines during primate synapse formation in late infancy and prepuberty (I). (United States)

    Sasaki, Tetsuya; Oga, Tomofumi; Nakagaki, Keiko; Sakai, Kazuhisa; Sumida, Kayo; Hoshino, Kohei; Miyawaki, Izuru; Saito, Koichi; Suto, Fumikazu; Ichinohe, Noritaka


    The synapse number and the related dendritic spine number in the cerebral cortex of primates shows a rapid increase after birth. Depending on the brain region and species, the number of synapses reaches a peak before adulthood, and pruning takes place after this peak (overshoot-type synaptic formation). Human mental disorders, such as autism and schizophrenia, are hypothesized to be a result of either too weak or excessive pruning after the peak is reached. Thus, it is important to study the molecular mechanisms underlying overshoot-type synaptic formation, particularly the pruning phase. To examine the molecular mechanisms, we used common marmosets (Callithrix jacchus). Microarray analysis of the marmoset cortex was performed in the ventrolateral prefrontal, inferior temporal, and primary visual cortices, where changes in the number of dendritic spines have been observed. The spine number of all the brain regions above showed a peak at 3 months (3 M) after birth and gradually decreased (e.g., at 6 M and in adults). In this study, we focused on genes that showed differential expression between ages of 3 M and 6 M and on the differences whose fold change (FC) was greater than 1.2. The selected genes were subjected to canonical pathway analysis, and in this study, we describe axon guidance signaling, which had high plausibility. The results showed a large number of genes belonging to subsystems within the axon guidance signaling pathway, macrophages/immune system, glutamate system, and others. We divided the data and discussion of these results into 2 papers, and this is the first paper, which deals with the axon guidance signaling and macrophage/immune system. Other systems will be described in the next paper. Many components of subsystems within the axon guidance signaling underwent changes in gene expression from 3 M to 6 M so that the synapse/dendritic spine number would decrease at 6 M. Thus, axon guidance signaling probably contributes to the decrease in

  20. A diet high in meat protein and potential renal acid load increases fractional Ca absorption and urinary Ca excretion, without affecting markers of bone resorption or formation in postmenopausal women (United States)

    Objective: The objective was to determine the effects of high dietary protein (mostly meat) and high potential renal acid load (PRAL) on calcium (Ca) balance and markers of bone metabolism. Methods: In a randomized crossover design, sixteen healthy postmenopausal women consumed two diets: one with l...

  1. The potential of at-home prediction of the formation of urolithiasis by simple multi-frequency electrical conductivity of the urine and the comparison of its performance with urine ion-related indices, color and specific gravity. (United States)

    Silverio, Angelito A; Chung, Wen-Yaw; Cheng, Cheanyeh; Wang, Hai-Lung; Kung, Chien-Min; Chen, Jun; Tsai, Vincent F S


    It is important to control daily diet, water intake and life style as well as monitor the quality of urine for urolithiasis prevention. For decades, many ion-related indices have been developed for predicting the formation of urinary stones or urolithiasis, such as EQUILs, relative supersaturation (RSS), Tiselius indices (TI), Robertson risk factor algorithms (RRFA) and more recently, the Bonn risk index. However, they mostly demand robust laboratory analysis, are work-intensive, and even require complex computational programs to get the concentration patterns of several urine analytes. A simple and fast platform for measuring multi-frequency electrical conductivity (MFEC) of morning spot urine (random urine) to predict the onset of urolithiasis was implemented in this study. The performance thereof was compared to ion-related indices, urine color and specific gravity. The concentrations of relevant ions, color, specific gravity (SG) and MFEC (MFEC tested at 1, 10, 100, 5001 KHz and 1 MHz) of 80 random urine samples were examined after collection. Then, the urine samples were stored at 4 °C for 24 h to determine whether sedimentation would occur or not. Ion-activity product index of calcium oxalate (AP(CaOx) EQ2) was calculated. The correlation between AP(CaOx) EQ2, urine color, SG and MFEC were analyzed. AP(CaOx) EQ2, urine color and MFEC (at 5 frequencies) all demonstrated good prediction (p = 0.01, 0.01, 0.01, respectively) for stone formation. The positive correlation between AP(CaOx) EQ2 and MFEC is also significant (p = 0.01). MFEC provides a good metric for predicting the onset of urolithiasis, which is comparable to conventional ion-related indices and urine color. This technology can be implemented with much ease for objectively monitoring the quality of urine at points-of-care or at home.

  2. 中国东部地区的O3污染形成机制及趋势的初步探讨%Ozone (O3) pollution in eastern China:It’s formation and a potential air quality problem in the region

    Institute of Scientific and Technical Information of China (English)

    铁学熙; 戴文婷


    improving of the aerosol pollution in China, the photo-chemical activities will be enhanced, leading to potential high O3 concentrations in China. The potential high ozone formation is also dependent on the emission ratio of NOx/VOCs. With the rapidly economical development in China, the VOC emission increases, leading to the decrease of emission ratio of NOx/VOCs. When the emission ratio of NOx/VOCs changes to lower than 0.2, the ozone formation is switched from VOC-limited condition to NOx-limited condition. As a result, the case of the photon-limit for the O3 formation decreases, leading to the enhancement of photo-chemical activists and potentially high O3 concentration in large cities in eastern China.Conclusions The tropospheric ozone formation is discussed under the heavy aerosol pollution condition in China. This study suggests that under the heavy aerosol pollution condition, the photo-chemical activity is greatly depressed, and O3 formation is signiifcantly decreased. In addition to the NOx-limit and VOCs-limit, this study suggests that the O3 formation in China is mainly under the photon-limit condition. Recommendations and perspectives With the improving of the aerosol pollution in China, the photo-chemical activities will enhance, leading to potential high O3 concentrations in the future. Attention should be paid for this serious environmental problem.%本文探讨了中国地区在高气溶胶污染下臭氧形成的问题。过去对臭氧污染的讨论主要集中在臭氧前提物(NOx, CO和VOCs)的讨论。并根据其各自的排放量研究臭氧形成在本地区是由NOx 还是VOCs控制的。然而,在中国高气溶胶频发的条件下,太阳辐射被强烈压抑,极大减少了臭氧形成的光化学过程。因此本文建议,除去臭氧形成的NOx 及VOCs控制条件,还应有一个太阳光子控制条件。而中国由于高气溶胶污染,目前臭氧的形成应是受太阳光子控制条件的影响。因此压抑了臭

  3. A fast formation process for lithium batteries (United States)

    Lee, Hsiang-Hwan; Wang, Yung-Yun; Wan, Chi-Chao; Yang, Mo-Hua; Wu, Hung-Chun; Shieh, Deng-Tswen

    The formation process presently used in the manufacture of lithium-ion batteries includes the solid electrolyte interface (SEI) growth process and another process for lithium intercalation into carbon. The latter process is both time and energy consuming. This study proposes a new concepts that can shorten the formation time by narrowing the potential range and bypassing the intercalation step during formation. The optimum cut-off voltage is 3.7 V for industrial LiCoO 2|C cells, and the formation time is reduced to less than one half of that required in the conventional formation procedure. Cycle performance is not affected significantly because the desired SEI growth is mainly completed in the potential range. These results suggest that the new method is superior to conventional formation.

  4. Learning Progressions that Support Formative Assessment Practices (United States)

    Alonzo, Alicia C.


    Black, Wilson, and Yao (this issue) lay out a comprehensive vision for the way that learning progressions (or other "road maps") might be used to inform and coordinate formative and summative purposes of assessment. As Black, Wilson, and others have been arguing for over a decade, the effective use of formative assessment has great potential to…

  5. Common File Formats. (United States)

    Mills, Lauren


    An overview of the many file formats commonly used in bioinformatics and genome sequence analysis is presented, including various data file formats, alignment file formats, and annotation file formats. Example workflows illustrate how some of the different file types are typically used.

  6. Swamp future. Energy for Western Pomerania Grid formation and potentials for the thermal utilization of biomass from paludi culture; MoorZukunft. Energie fuer Vorpommern. Netzwerkbildung und Potentiale fuer die thermische Verwertung von Biomasse aus Paludikultur

    Energy Technology Data Exchange (ETDEWEB)

    Nordt, Anke; Schroeder, Christian [Greifswald Univ. (Germany). Inst. fuer Botanik und Landschaftsoekologie; Schroeder, Philipp


    MoorZukunft aims to initiate pilot projects for utilisation biomass from ''wet'' peatland for energy purposes. Also alternative concepts of funding regional cooperations are to be developed. The implementation of paludiculture, the sustainable cultivation of rewetted peatland, needs innovative unions between farmers who produce primary material for paludi-products and biomass consumers for energy or material utilisation. Areas for implementing paludiculture are identified and potential partners for regional use and consumption are cross-linked. Business models will be developed with the parties of possible cooperations, i.g. between farmer and municipal energy supplier and functional attended until realisation. The procedure to initiate pilot projects will be explained. This expands from requests of areas and partners until possible forms of organisation locally shared utilisation partnerships. (orig.)

  7. The Format Registry Problem

    Directory of Open Access Journals (Sweden)

    Gary McGath


    Full Text Available File format identification is an important issue in digital preservation. Several noteworthy attempts, including PRONOM, GDFR, and UDFR, have been made at creating a comprehensive repository of format information. The sheer amount of information to cover and the constant introduction of new formats and format versions has limited their success. Alternative approaches, such as Linked Data and offering limited per-format information with identifiers that can be used elsewhere, may lead to greater success.

  8. Potential Theory

    CERN Document Server

    Lukeš, Jaroslav; Netuka, Ivan; Veselý, Jiří


    Within the tradition of meetings devoted to potential theory, a conference on potential theory took place in Prague on 19-24, July 1987. The Conference was organized by the Faculty of Mathematics and Physics, Charles University, with the collaboration of the Institute of Mathematics, Czechoslovak Academy of Sciences, the Department of Mathematics, Czech University of Technology, the Union of Czechoslovak Mathematicians and Physicists, the Czechoslovak Scientific and Technical Society, and supported by IMU. During the Conference, 69 scientific communications from different branches of potential theory were presented; the majority of them are in­ cluded in the present volume. (Papers based on survey lectures delivered at the Conference, its program as well as a collection of problems from potential theory will appear in a special volume of the Lecture Notes Series published by Springer-Verlag). Topics of these communications truly reflect the vast scope of contemporary potential theory. Some contributions deal...

  9. Dense Cloud Formation and Star Formation in a Barred Galaxy

    CERN Document Server

    Nimori, M; Sorai, K; Watanabe, Y; Hirota, A; Namekata, D


    We investigate the properties of massive, dense clouds formed in a barred galaxy and their possible relation to star formation, performing a two-dimensional hydrodynamical simulation with the gravitational potential obtained from the 2Mass data from the barred spiral galaxy, M83. Since the environment for cloud formation and evolution in the bar region is expected to be different from that in the spiral arm region, barred galaxies are a good target to study the environmental effects on cloud formation and the subsequent star formation. Our simulation uses for an initial 80 Myr an isothermal flow of non-self gravitating gas in the barred potential, then including radiative cooling, heating and self-gravitation of the gas for the next 40 Myr, during which dense clumps are formed. We identify many cold, dense gas clumps for which the mass is more than $10^4M_{\\odot}$ (a value corresponding to the molecular clouds) and study the physical properties of these clumps. The relation of the velocity dispersion of the i...

  10. Losses of the potential in methane formation during the storage of sugar beet pulp in open ground basins; Verluste an Methanbildungspotenzial bei der Lagerung von Zuckerruebenmus in offenen Erdbecken

    Energy Technology Data Exchange (ETDEWEB)

    Parr, Klaus [Gut Dummerstorf GmbH, Dummerstorf (Germany); Reinsdorf, Uwe; Warnke-Gurgel, Christina [NAWARO BioEnergie Park Guestrow GmbH, Guestrow (Germany); Losand, Bernd [Landesforschungsanstalt fuer Landwirtschaft und Fischerei Mecklenburg-Vorpommern, Dummerstorf (Germany); Weissbach, Friedrich


    For the use as a substrate in biogas production, it has been proposed to pulpify sugar beets and to store this material in open ground basins (lagoons) which are lined with plastic film. In the inner regions of the lagoon, the material is preserved by anaerobic conditions and lactic acid fermentation. In the surface layer, which is exposed to the atmosphere, however, additional losses are generated by aerobic substrate degradation and evaporation of volatile compounds. The objective of this joined experimental study was to examine the losses of methane forming potential (MFP) during storage of pulpified sugar beets in lagoons. For this purpose, a method was developed enabling the quantification of these losses without the need of a mass balance. This method uses the changes of ash content of dry matter as an internal marker. The results obtained in this way are suitable to calculate the losses which are to be expected during conservation of pulpified sugar beets in open storage facilities of any volume and geometric form. The losses during an all year round storage of pulpified beet mass in lagoons proved to be higher than commonly assumed. In lagoons of 3 to 4 m of depth, the losses according to this study amounted to about 25% of organic matter and about 20% of MFP. (orig.)

  11. 中职学校数学“潜能生”的成因及转化措施初探%Cause of Formation of Secondary Vocational School "Potential Students of Mathematics" and Transformation Measures

    Institute of Scientific and Technical Information of China (English)



    因为受社会环境、家庭氛围、智力差异、学习方法、个性品质以及教师的教学方式等诸多因素的影响,必然会有一部分学生成为所谓的数学“潜能生”,面向这样的学生,最大限度地满足他们的数学需要,让他们学习有价值的数学.我们数学教师就要剖析原因,采取积极地措施,对他们进行教育和转化,在数学上也能有成功的体验,这就是我们必须研究的课题.%Because of the social environment, family atmosphere, differences in intelligence, personality, learning methods and teaching methods and many other factors, there must be a part of the students to become the so-called "potential students of mathematics", facing such students, the maximum to meet their mathematics needs, let them learn valuable mathematics. Our maths teacher is to analyze the reason, take active measures, their education and transformation in mathematics, also can have a successful experience in mathematics, this is the issue that we must study.

  12. Violent Potentials

    DEFF Research Database (Denmark)

    Mikkelsen, Henrik Hvenegaard; Søgaard, Thomas Friis


    This article explores the social significance of violence as potentiality and performance among former headhunters. Taking its outset in an ethnographic study of violence and masculinity among the Philippine people known as the Bugkalot, we explore how violence as “performed violent potentiality......” plays a critical role in relation to Bugkalot men’s construction of hegemonic masculinity and the sustaining of complex egalitarian relations. The Bugkalot have a notoriously violent history; until the late 1970s more than half of the adult men engaged in ritual killings. While most Bugkalot men has...... today abandoned headhunting, the potentials for violence and dominance, which the act of headhunting sought to elicit, remains a critical aspect of masculinity. We propose that a focus on the social significance of performative violent potentiality among Bugkalot men can provide general insights...

  13. 粉煤灰合成沸石过程溶解性机理及吸附潜能研究%Dissolution Mechanisms of Zeolite Formation from Coal Fly Ash and Its Adsorption Potential

    Institute of Scientific and Technical Information of China (English)

    陈晓燕; 李江丽; 王行; 周林强; 张志剑


    本文研究了温度、碱度、液固比(L/S)及反应时间对粉煤灰水热法合成沸石过程中其溶解性的影响,结果表明在溶解阶段.反应时间、温度、碱度及液固比与粉煤灰的溶解性成正相关,而随着反应进入到结晶阶段,溶解的si和Al逐渐组合成沸石.在温度为95℃、L/S为6 mL/g、碱浓度(NaOH)为2 mol/L的条件下,Na-Pl沸石的合成在96h时产量最高,同时其阳离子交换容量(CEC)为206.7 cmol/kg,比表面积(SSA)为37.7 m/g,分别是原样粉煤灰的125倍和34倍,在水环境污染物吸附方面具有较大的应用潜能.%The effects of reaction temperature, alkalinity level, liquid-solid ratio (L/S) and reaction time on hydrothermal synthesis zeolite fiom coal fly ash were studied. The results showed that the reaction time, temperature, alkalinity and L/S ratio were positively related to the solubility of coal fly ash during its dissolution stage. In the following crystalline phase, the dissolved Si and Al gradually formed into zeolite. At the temperature of 95 ℃, L/S = 6 mL/g, C (NaOH) = 2 moL/L, the yield of synthesized zeolite Na-P1 reached the highest level at 96 h. The synthesized product had the cation exchange capacity (CEC) of 206.7 cmol/kg and specific surface area (SSA) of 37.7 m2/g, being 125 times and 34 times of the raw coal fly ash, respectively. The combined zeolite obtained fiom coal fly ash showed a large adsorption potential in environmental contaminants treatments.

  14. Autonomous Formations of Multi-Agent Systems (United States)

    Dhali, Sanjana; Joshi, Suresh M.


    Autonomous formation control of multi-agent dynamic systems has a number of applications that include ground-based and aerial robots and satellite formations. For air vehicles, formation flight ("flocking") has the potential to significantly increase airspace utilization as well as fuel efficiency. This presentation addresses two main problems in multi-agent formations: optimal role assignment to minimize the total cost (e.g., combined distance traveled by all agents); and maintaining formation geometry during flock motion. The Kuhn-Munkres ("Hungarian") algorithm is used for optimal assignment, and consensus-based leader-follower type control architecture is used to maintain formation shape despite the leader s independent movements. The methods are demonstrated by animated simulations.

  15. Simple Ontology Format (SOFT)

    Energy Technology Data Exchange (ETDEWEB)


    Simple Ontology Format (SOFT) library and file format specification provides a set of simple tools for developing and maintaining ontologies. The library, implemented as a perl module, supports parsing and verification of the files in SOFt format, operations with ontologies (adding, removing, or filtering of entities), and converting of ontologies into other formats. SOFT allows users to quickly create ontologies using only a basic text editor, verify it, and portray it in a graph layout system using customized styles.

  16. Violent potentials

    DEFF Research Database (Denmark)

    Mikkelsen, Henrik Hvenegaard; Friis Søgaard, Thomas


    as ‘performed violent potentiality’ plays a critical role in relation to Bugkalot men’s construction of hegemonic masculinity and the sustaining of complex egalitarian relations. The Bugkalot have a notoriously violent history; until the late 1970s more than half of the adult men engaged in ritual killings......This article explores the social significance of violence as potentiality and performance among former headhunters engaged in ritual killings. Taking its outset in an ethnographic study of violence and masculinity among the Philippine people known as the Bugkalot, we explore how violence....... While most Bugkalot men have today abandoned headhunting, the potentials for violence and dominance, which the act of headhunting sought to elicit, remains a critical aspect of masculinity. We propose that a focus on the social significance of performative violent potentiality among Bugkalot men can...

  17. Innovative potential, innovative strategy, environment factors, estimation of innovative potential, innovative development


    Chernoivanova, G.


    The paper summarizes the elements of the innovation potential and the criteria for its evaluation. It is proposed methodical approach to the formation of innovation strategies with innovative potential.

  18. Violent Potentials

    DEFF Research Database (Denmark)

    Mikkelsen, Henrik Hvenegaard; Søgaard, Thomas Friis


    This article explores the social significance of violence as potentiality and performance among former headhunters. Taking its outset in an ethnographic study of violence and masculinity among the Philippine people known as the Bugkalot, we explore how violence as “performed violent potentiality”...

  19. Isolating Triggered Star Formation

    CERN Document Server

    Barton, Elizabeth J; Zentner, Andrew R; Bullock, James S; Wechsler, Risa H


    Galaxy pairs provide a potentially powerful means of studying triggered star formation from galaxy interactions. We use a large cosmological N-body simulation coupled with a well-tested semi-analytic substructure model to demonstrate that the majority of galaxies in close pairs reside within cluster or group-size halos and therefore represent a biased population, poorly suited for direct comparison to ``field'' galaxies. Thus, the frequent observation that some types of galaxies in pairs have redder colors than ``field'' galaxies is primarily a selection effect. We select galaxy pairs that are isolated in their dark matter halos with respect to other massive subhalos (N=2 halos) and a control sample of isolated galaxies (N=1 halos) for comparison. We then apply these selection criteria to a volume-limited subset of the 2dF Galaxy Redshift Survey with M_Bj ~ 5 above their average past value, while only 10% of isolated galaxies in the control sample show this level of enhancement. Thus, 14% (20 %) of the galaxi...

  20. Dynamic formation control for autonomous underwater vehicles

    Institute of Scientific and Technical Information of China (English)

    燕雪峰; 古锋; 宋琛; 胡晓琳; 潘毅


    Path planning and formation structure forming are two of the most important problems for autonomous underwater vehicles (AUVs) to collaborate with each other. In this work, a dynamic formation model was proposed, in which several algorithms were developed for the complex underwater environment. Dimension changeable particle swarm algorithm was used to find an optimized path by dynamically adjusting the number and the distribution of the path nodes. Position relationship based obstacle avoidance algorithm was designed to detour along the edges of obstacles. Virtual potential point based formation-keeping algorithm was employed by incorporating dynamic strategies which were decided by the current states of the formation. The virtual potential point was used to keep the formation structure when the AUV or the formation was deviated. Simulation results show that an optimal path can be dynamically planned with fewer path nodes and smaller fitness, even with a concave obstacle. It has been also proven that different formation-keeping strategies can be adaptively selected and the formation can change its structure in a narrow area and restore back after passing the obstacle.

  1. Potential theory

    CERN Document Server

    Helms, Lester L


    Potential Theory presents a clear path from calculus to classical potential theory and beyond, with the aim of moving the reader into the area of mathematical research as quickly as possible. The subject matter is developed from first principles using only calculus. Commencing with the inverse square law for gravitational and electromagnetic forces and the divergence theorem, the author develops methods for constructing solutions of Laplace's equation on a region with prescribed values on the boundary of the region. The latter half of the book addresses more advanced material aimed at those with the background of a senior undergraduate or beginning graduate course in real analysis. Starting with solutions of the Dirichlet problem subject to mixed boundary conditions on the simplest of regions, methods of morphing such solutions onto solutions of Poisson's equation on more general regions are developed using diffeomorphisms and the Perron-Wiener-Brelot method, culminating in application to Brownian motion. In ...

  2. Star Formation for Predictive Primordial Galaxy Formation (United States)

    Milosavljević, Miloš; Safranek-Shrader, Chalence

    The elegance of inflationary cosmology and cosmological perturbation theory ends with the formation of the first stars and galaxies, the initial sources of light that launched the phenomenologically rich process of cosmic reionization. Here we review the current understanding of early star formation, emphasizing unsolved problems and technical challenges. We begin with the first generation of stars to form after the Big Bang and trace how they influenced subsequent star formation. The onset of chemical enrichment coincided with a sharp increase in the overall physical complexity of star forming systems. Ab-initio computational treatments are just now entering the domain of the predictive and are establishing contact with local observations of the relics of this ancient epoch.

  3. Formation Flying Concept Issues

    Directory of Open Access Journals (Sweden)

    M. V. Palkin


    Full Text Available The term “formation flying” implies coordinated movement of at least two satellites on coplanar and non-coplanar orbits with a maximum distance between them being much less than the length of the orbit. Peculiarities of formation flying concept also include:- automatic coordination of satellites;- sub-group specialization of formation flying satellites;- equipment and data exchange technology unification in each specialized group or subgroup.Formation flying satellites can be classified according to the configuration stability level (order (array, cluster («swarm», intergroup specialization rules («central satellite», «leader», «slave», manoeuvrability («active» and «passive» satellites.Tasks of formation flying include:- experiments with payload, distributed in formation flying satellites;- various near-earth space and earth-surface research;- super-sized aperture antenna development;- land-based telescope calibration;- «space advertisement» (earth-surface observable satellite compositions of a logotype, word, etc.;- orbital satellite maintenance, etc.Main issues of formation flying satellite system design are:- development of an autonomous satellite group manoeuvring technology;- providing a sufficient characteristic velocity of formation flying satellites;- ballistic and navigation maintenance for satellite formation flying;- technical and economic assessment of formation flying orbital delivery and deployment;- standardization, unification, miniaturization and integration of equipment;- intergroup and intersatellite function redistribution.

  4. Potential cellular and molecular causes of hypertrophic scar formation

    NARCIS (Netherlands)

    van der Veer, Willem M.; Bloemen, Monica C. T.; Ulrich, Magda M. W.; Molema, Grietje; van Zuijlen, Paul P.; Middelkoop, Esther; Niessen, Frank B.


    A scar is an expected result of wound healing. However, in some individuals, and particularly in burn victims, the wound healing processes may lead to a fibrotic hypertrophic scar, which is raised, red, inflexible and responsible serious functional and cosmetic problems. It seems that a wide array o

  5. Potential cellular and molecular causes of hypertrophic scar formation

    NARCIS (Netherlands)

    Veer, van der W.M.; Bloemen, M.C.; Ulrich, M.; Molema, G.; Zuijlen, van P.P.; Middelkoop, E.; Niessen, F.B.


    A scar is an expected result of wound healing. However, in some individuals, and particularly in burn victims, the wound healing processes may lead to a fibrotic hypertrophic scar, which is raised, red, inflexible and responsible for serious functional and cosmetic problems. It seems that a wide arr

  6. Potential cellular and molecular causes of hypertrophic scar formation

    NARCIS (Netherlands)

    van der Veer, Willem M.; Bloemen, Monica C. T.; Ulrich, Magda M. W.; Molema, Grietje; van Zuijlen, Paul P.; Middelkoop, Esther; Niessen, Frank B.

    A scar is an expected result of wound healing. However, in some individuals, and particularly in burn victims, the wound healing processes may lead to a fibrotic hypertrophic scar, which is raised, red, inflexible and responsible serious functional and cosmetic problems. It seems that a wide array

  7. Potential cellular and molecular causes of hypertrophic scar formation

    NARCIS (Netherlands)

    Veer, van der W.M.; Bloemen, M.C.; Ulrich, M.; Molema, G.; Zuijlen, van P.P.; Middelkoop, E.; Niessen, F.B.


    A scar is an expected result of wound healing. However, in some individuals, and particularly in burn victims, the wound healing processes may lead to a fibrotic hypertrophic scar, which is raised, red, inflexible and responsible for serious functional and cosmetic problems. It seems that a wide

  8. Zeolite formation from coal fly ash and its adsorption potential. (United States)

    Ruen-ngam, Duangkamol; Rungsuk, Doungmanee; Apiratikul, Ronbanchob; Pavasant, Prasert


    The possibility in converting coal fly ash (CFA) to zeolite was evaluated. CFA samples from the local power plant in Prachinburi province, Thailand, were collected during a 3-month time span to account for the inconsistency of the CFA quality, and it was evident that the deviation of the quality of the raw material did not have significant effects on the synthesis. The zeolite product was found to be type X. The most suitable weight ratio of sodium hydroxide (NaOH) to CFA was approximately 2.25, because this gave reasonably high zeolite yield with good cation exchange capacity (CEC). The silica (Si)-to-aluminum (Al) molar ratio of 4.06 yielded the highest crystallinity level for zeolite X at 79% with a CEC of 240 meq/100 g and a surface area of 325 m2/g. Optimal crystallization temperature and time were 90 degrees C and 4 hr, respectively, which gave the highest CEC of approximately 305 meq/100 g. Yields obtained from all experiments were in the range of 50-72%.

  9. Reduction of potential formation of haloacetics acids in natural waters


    M'Birek, Chafik; Sentana Gadea, Irene; Cartagena Quinto, Pablo; Rodríguez Pastor, Manuel; Prats Rico, Daniel


    Póster presentado en 11th Mediterranean Congress in Chemical Engineering "Chemical Engineering in the Frontiers of Knowledge", Barcelona, 21-24 October 2008. This study was financial supported by the “Generalitat Valenciana GV07/129 ” of the Spanish Government.

  10. Promoting proximal formative assessment with relational discourse (United States)

    Scherr, Rachel E.; Close, Hunter G.; McKagan, Sarah B.


    The practice of proximal formative assessment - the continual, responsive attention to students' developing understanding as it is expressed in real time - depends on students' sharing their ideas with instructors and on teachers' attending to them. Rogerian psychology presents an account of the conditions under which proximal formative assessment may be promoted or inhibited: (1) Normal classroom conditions, characterized by evaluation and attention to learning targets, may present threats to students' sense of their own competence and value, causing them to conceal their ideas and reducing the potential for proximal formative assessment. (2) In contrast, discourse patterns characterized by positive anticipation and attention to learner ideas increase the potential for proximal formative assessment and promote self-directed learning. We present an analysis methodology based on these principles and demonstrate its utility for understanding episodes of university physics instruction.

  11. Massive Star Formation: The Power of Interferometry

    CERN Document Server

    Beuther, Henrik


    This article presents recent work to constrain the physical and chemical properties in high-mass star formation based largely on interferometric high-spatial-resolution continuum and spectral line studies at (sub)mm wavelengths. After outlining the concepts, potential observational tests, a proposed evolutionary sequence and different possible definitions for massive protostars, four particular topics are highlighted: (a) What are the physical conditions at the onset of massive star formation? (b) What are the characteristics of potential massive accretion disks and what do they tell us about massive star formation in general? (c) How do massive clumps fragment, and what does it imply to high-mass star formation? (d) What do we learn from imaging spectral line surveys with respect to the chemistry itself as well as for utilizing molecules as tools for astrophysical investigations?

  12. Formation of Supermassive Black Holes

    CERN Document Server

    Volonteri, Marta


    Evidence shows that massive black holes reside in most local galaxies. Studies have also established a number of relations between the MBH mass and properties of the host galaxy such as bulge mass and velocity dispersion. These results suggest that central MBHs, while much less massive than the host (~ 0.1%), are linked to the evolution of galactic structure. In hierarchical cosmologies, a single big galaxy today can be traced back to the stage when it was split up in hundreds of smaller components. Did MBH seeds form with the same efficiency in small proto-galaxies, or did their formation had to await the buildup of substantial galaxies with deeper potential wells? I briefly review here some of the physical processes that are conducive to the evolution of the massive black hole population. I will discuss black hole formation processes for `seed' black holes that are likely to place at early cosmic epochs, and possible observational tests of these scenarios.

  13. The Conic Benchmark Format

    DEFF Research Database (Denmark)

    Friberg, Henrik A.

    This document constitutes the technical reference manual of the Conic Benchmark Format with le extension: .cbf or .CBF. It unies linear, second-order cone (also known as conic quadratic) and semidenite optimization with mixed-integer variables. The format has been designed with benchmark libraries...... in mind, and therefore focuses on compact and easily parsable representations. The problem structure is separated from the problem data, and the format moreover facilitate benchmarking of hotstart capability through sequences of changes....

  14. Source rock potential in Pakistan

    Energy Technology Data Exchange (ETDEWEB)

    Raza, H.A. (Hydrocarbon Development Institute of Pakistan, Islamabad (Pakistan))


    Pakistan contains two sedimentary basins: Indus in the east and Balochistan in the west. The Indus basin has received sediments from precambrian until Recent, albeit with breaks. It has been producing hydrocarbons since 1914 from three main producing regions, namely, the Potwar, Sulaisman, and Kirthar. In the Potwar, oil has been discovered in Cambrian, Permian, Jurassic, and Tertiary rocks. Potential source rocks are identified in Infra-Cambrian, Permian, Paleocene, and Eocene successions, but Paleocene/Eocene Patala Formation seems to be the main source of most of the oil. In the Sulaiman, gas has been found in Cretaceous and Tertiary; condensate in Cretaceous rocks. Potential source rocks are indicated in Cretaceous, Paleocene, and Eocene successions. The Sembar Formation of Early Cretaceous age appears to be the source of gas. In the Kirthar, oil and gas have been discovered in Cretaceous and gas has been discovered in paleocene and Eocene rocks. Potential source rocks are identified in Kirthar and Ghazij formations of Eocene age in the western part. However, in the easter oil- and gas-producing Badin platform area, Union Texas has recognized the Sembar Formation of Early Cretaceous age as the only source of Cretaceous oil and gas. The Balochistan basin is part of an Early Tertiary arc-trench system. The basin is inadequately explored, and there is no oil or gas discovery so far. However, potential source rocks have been identified in Eocene, Oligocene, Miocene, and Pliocene successions based on geochemical analysis of surface samples. Mud volcanoes are present.

  15. Adaptive Swarm Formation Control for Hybrid Ground and Aerial Assets


    Barnes, Laura; Garcia, Richard; Fields, Mary Anne; Valavanis, Kimon


    In this work, a methodology for control and coordination of UAVs and UGVs has been presented. UAVs and UGVs were integrated into a single team and were able to adapt their formation accordingly. Potential field functions together with limiting functions can be successfully utilized to control UGV and UAV swarm formation, obstacle avoidance and the overall swarm movement. A single UAV was also successfully used to pull the UGV swarm into formation. These formations can move as a un...

  16. Formative Assessment in Context (United States)

    Oxenford-O'Brian, Julie


    This dissertation responds to critical gaps in current research on formative assessment practice which could limit successful implementation of this practice within the K-12 classroom context. The study applies a socio cultural perspective of learning to interpret a cross-case analysis of formative assessment practice occurring during one…

  17. Formation of multiple networks

    DEFF Research Database (Denmark)

    Magnani, Matteo; Rossi, Luca


    we introduce the first network formation model for multiple networks. Network formation models are among the most popular tools in traditional network studies, because of both their practical and theoretical impact. However, existing models are not sufficient to describe the generation of multiple...

  18. Isothermal Martensite Formation

    DEFF Research Database (Denmark)

    Villa, Matteo

    Isothermal (i.e. time dependent) martensite formation in steel was first observed in the 40ies of the XXth century and is still treated as an anomaly in the description of martensite formation which is considered as a-thermal (i.e. independent of time). Recently, the clarification of the mechanis...

  19. Galaxy Formation Theory

    CERN Document Server

    Benson, Andrew J


    We review the current theory of how galaxies form within the cosmological framework provided by the cold dark matter paradigm for structure formation. Beginning with the pre-galactic evolution of baryonic material we describe the analytical and numerical understanding of how baryons condense into galaxies, what determines the structure of those galaxies and how internal and external processes (including star formation, merging, active galactic nuclei etc.) determine their gross properties and evolution. Throughout, we highlight successes and failings of current galaxy formation theory. We include a review of computational implementations of galaxy formation theory and assess their ability to provide reliable modeling of this complex phenomenon. We finish with a discussion of several "hot topics" in contemporary galaxy formation theory and assess future directions for this field.

  20. Usage Record Format Recommendation

    CERN Document Server

    Nilsen, J.K.; Muller-Pfeerkorn, R


    For resources to be shared, sites must be able to exchange basic accounting and usage data in a common format. This document describes a common format which enables the exchange of basic accounting and usage data from different resources. This record format is intended to facilitate the sharing of usage information, particularly in the area of the accounting of jobs, computing, memory, storage and cloud usage but with a structure that allows an easy extension to other resources. This document describes the Usage Record components both in natural language form and annotated XML. This document does not address how these records should be used, nor does it attempt to dictate the format in which the accounting records are stored. Instead, it denes a common exchange format. Furthermore, nothing is said regarding the communication mechanisms employed to exchange the records, i.e. transport layer, framing, authentication, integrity, etc.

  1. Control of groundwater pH during bioremediation: Improvement and validation of a geochemical model to assess the buffering potential of ground silicate minerals (United States)

    Lacroix, Elsa; Brovelli, Alessandro; Holliger, Christof; Barry, D. A.


    Accurate control of groundwater pH is of critical importance for in situ biological treatment of chlorinated solvents. The use of ground silicate minerals mixed with groundwater is an appealing buffering strategy as silicate minerals may act as long-term sources of alkalinity. In a previous study, we developed a geochemical model for evaluation of the pH buffering capacity of such minerals. The model included the main microbial processes driving groundwater acidification as well as mineral dissolution. In the present study, abiotic mineral dissolution experiments were conducted with five silicate minerals (andradite, diopside, fayalite, forsterite, nepheline). The goal of the study was to validate the model and to test the buffering capacity of the candidate minerals identified previously. These five minerals increased the pH from acidic to neutral and slightly basic values. The model was revised and improved to represent better the experimental observations. In particular, the experiments revealed the importance of secondary mineral precipitation on the buffering potential of silicates, a process not included in the original formulation. The main secondary phases likely to precipitate were identified through model calibration, as well as the degree of saturation at which they formed. The predictions of the revised geochemical model were in good agreement with the observations, with a correlation coefficient higher than 0.9 in most cases. This study confirmed the potential of silicates to act as pH control agents and showed the reliability of the geochemical model, which can be used as a design tool for field applications.

  2. Control of groundwater pH during bioremediation: improvement and validation of a geochemical model to assess the buffering potential of ground silicate minerals. (United States)

    Lacroix, Elsa; Brovelli, Alessandro; Holliger, Christof; Barry, D A


    Accurate control of groundwater pH is of critical importance for in situ biological treatment of chlorinated solvents. The use of ground silicate minerals mixed with groundwater is an appealing buffering strategy as silicate minerals may act as long-term sources of alkalinity. In a previous study, we developed a geochemical model for evaluation of the pH buffering capacity of such minerals. The model included the main microbial processes driving groundwater acidification as well as mineral dissolution. In the present study, abiotic mineral dissolution experiments were conducted with five silicate minerals (andradite, diopside, fayalite, forsterite, nepheline). The goal of the study was to validate the model and to test the buffering capacity of the candidate minerals identified previously. These five minerals increased the pH from acidic to neutral and slightly basic values. The model was revised and improved to represent better the experimental observations. In particular, the experiments revealed the importance of secondary mineral precipitation on the buffering potential of silicates, a process not included in the original formulation. The main secondary phases likely to precipitate were identified through model calibration, as well as the degree of saturation at which they formed. The predictions of the revised geochemical model were in good agreement with the observations, with a correlation coefficient higher than 0.9 in most cases. This study confirmed the potential of silicates to act as pH control agents and showed the reliability of the geochemical model, which can be used as a design tool for field applications.

  3. When efficient star formation drives cluster formation

    CERN Document Server

    Parmentier, G


    We investigate the impact of the star formation efficiency in cluster forming cores on the evolution of the mass in star clusters over the age range 1-100Myr, when star clusters undergo their infant weight-loss/mortality phase. Assuming a constant formation rate of gas-embedded clusters and a weak tidal field, we show that the ratio between the total mass in stars bound to the clusters over that age range and the total mass in stars initially formed in gas-embedded clusters is a strongly increasing function of the averaged local SFE, with little influence from any assumed core mass-radius relation. Our results suggest that, for young starbursts with estimated tidal field strength and known recent star formation history, observed cluster-to-star mass ratios, once corrected for the undetected clusters, constitute promising probes of the local SFE, without the need of resorting to gas mass estimates. Similarly, the mass ratio of stars which remain in bound clusters at the end of the infant mortality/weight-loss ...

  4. Boron - A potential goiterogen? (United States)

    Popova, Elizaveta V; Tinkov, Alexey A; Ajsuvakova, Olga P; Skalnaya, Margarita G; Skalny, Anatoly V


    The iodine deficiency disorders (IDD) include a variety of disturbances such as decreased fertility, increased perinatal and infant mortality, impaired physical and intellectual development, mental retardation, cretinism, hypothyroidism, and endemic goiter (EG). The occurrence of the latter is determined by interplay between genetic and environmental factors. The major environmental factor is iodine status that is required for normal thyroid hormone synthesis. However, other factors like intake of micronutrients and goiterogens also have a significant impact. Essential and toxic trace elements both play a significant role in thyroid physiology. We hypothesize that in terms of overexposure boron may serve as a potential goiterogen. In particular, it is proposed that boron overload may impair thyroid physiology ultimately leading to goiter formation. Certain studies provide evidential support of the hypothesis. In particular, it has been demonstrated that serum and urinary B levels are characterized by a negative association with thyroid hormone levels in exposed subjects. Single indications on the potential efficiency of B in hypothyroidism also exist. Moreover, the levels of B were found to be interrelated with thyroid volume in children environmentally exposed to boron. Experimental studies also demonstrated a significant impact of boron on thyroid structure and hormone levels. Finally, the high rate of B cumulation in thyroid may also indicate that thyroid is the target for B activity. Chemical properties of iodine and boron also provide a background for certain competition. However, it is questionable whether these interactions may occur in the biological systems. Further clinical and experimental studies are required to support the hypothesis of the involvement of boron overexposure in goiter formation. If such association will be confirmed and the potential mechanisms elucidated, it will help to regulate the incidence of hypothyroidism and goiter in endemic

  5. Geophysical Processes - MO 2013 Landslide Potential (SHP) (United States)

    NSGIC GIS Inventory (aka Ramona) — Landslide potential is based on slope and lithology. Landslide is considered probable if the slope is 12 percent or greater and correlated with a formation known to...

  6. Distribution of disinfection by-product formation potential by chlor(am)ination in three megalopolis along Yangtze river%长江沿线城市水源氯(胺)化消毒副产物生成潜能研究

    Institute of Scientific and Technical Information of China (English)

    黄河; 徐斌; 朱文倩; 秦朗; 马玉英


    Dissolved organic matter (DOM) in raw water from upper Yangtze River in Chongqing, middle Yangtze River in Wuhan, lower Yangtze River in Shanghai was isolated into fractions with different hydrophobicity and molecular weight (MW) by resin adsorption and ultra-filtration, respectively, to investigate and regulate emerging disinfection byproducts formation potential during chlorination and chloramination for each fraction. Research showted that DOM from Chongqing, Wuhan and Shanghai was mainly constituted of MW<1kDa organic compounds, hydrophilic and hydrophobic fractions. Trihalometheanes, haloketones, haloacetic acids, haloacetonitriles and chloropicrin were formed after chlorination and chloramination. Among three cities, MW<1kDa fractions gave the highest yield of carbonaceous disinfection byproducts (C-DBPs) and nitrogenous disinfection byproducts (N-DBPs), and the proportion of MW<1kDa formation potential tended to ascend from the upper Yangtze River to lower Yangtze River;Among all three megalopolis, hydrophobic fraction and hydrophilic fraction produced more C-DBPs and N-DBPs, the proportion of hydrophilic fraction C-DBPs and N-DBPs formation potential tended to ascend during chloramination.%以长江上游重庆、中游武汉、下游上海等大城市的长江饮用水源为研究对象,在对溶解性有机物分子量和亲疏水性分离的基础上,分别采用氯和氯胺两种方式消毒,对比分析了相同时期沿江这些城市原水中氯(胺)化常规和新兴含氮消毒副产物生成潜能的分子组成规律。研究表明,重庆、武汉、上海三地的溶解性有机物均以小分子前体物为主,主要分布在<1kDa 的区间内,且以强疏水性成分和亲水性成分为主,原水经氯(胺)化可产生三卤甲烷、卤乙酸、卤乙腈、三氯硝基甲烷等类型的消毒副产物;三地的氯(胺)化主要的含碳消毒副产物(C-DBPs)和含氮消毒副产物(N-DBPs)生成潜能均在<1kDa的区间内

  7. Formation of "bound (United States)

    Nowak, K.; Kästner, M.; Miltner, A.


    During degradation of organic pollutants in soil, metabolites, microbial biomass, CO2and "bound" residues ("non-extractable" residues in soil organic matter) are formed. Enhanced transformation of these contaminants into "bound" residues has been proposed as an alternative remediation method for polluted soils. However, this kind of residues may pose a potential risk for the environment due to their chemical structure and possible remobilization under different conditions. Therefore particular attention is given actually to "bound" residues. Part of these non-extractable residues may be "biogenic," because microorganisms use the carbon from the pollutant to form their biomass components (fatty acids, amino acids, amino sugars), which subsequently may be incorporated into soil organic matter. Furthermore, the CO2 originating from mineralization of xenobiotics, can be re-assimilated by microorganisms and also incorporated into "biogenic residue". The hazard posed by "bound" residues may be overestimated because they are "biogenic" (contain microbial fatty acids and amino acids). The knowledge about the pathways of "biogenic residue" formation is necessary for a proper assessment of the fate of tested pollutants and their turnover in the soil environment. Moreover, these data are needed to establish the realistic degradation rates of the contaminants in soil. The main objectives of this study are: to quantify the extent of "biogenic residue" (fatty acids, amino acids, amino sugars) formation during the degradation of a model pollutant (2,4-dichlorophenoxyacetic acid = 2,4-D) and during CO2 assimilation by microorganisms and to evaluate which components are mainly incorporated into "bound" residues. To investigate the extent of "biogenic residue" formation in soil during the degradation of 2,4-D, experiments with either 14C-U-ring and 13C6-2,4-D or carboxyl-14C 2,4-D were performed. The incubation experiments were performed according to OECD test guideline 307, in the

  8. Estimates of global dew collection potential


    Vuollekoski, H.; Vogt, M.; Sinclair, V. A.; Duplissy, J; Järvinen, H; E.-M. Kyrö; R. Makkonen; T. Petäjä; N. L. Prisle; Räisänen, P.; M. Sipilä; J. Ylhäisi; Kulmala, M


    The global potential for collecting usable water from dew on an artificial collector sheet was investigated by utilising 34 years of meteorological reanalysis data as input to a dew formation model. Dew formation was found to be frequent and common, but daily yields were mostly below 0.1 mm. Nevertheless, some water-stressed areas such as the coastal regions of northern Africa and the Arabian Peninsula show potential for large-scale dew ...

  9. Methemoglobin formation by paraquat.

    Directory of Open Access Journals (Sweden)



    Full Text Available Paraquat is a broad spectrum herbicide known to be highly lethal to man and animals. Its toxicity is characterized by acute lung injury. Paraquat produces such toxic effects through the generation of the superoxide anion according to one proposed mechanism. The present experiment, methemoglobin formation was demonstrated after incubation of oxyhemoglobin with paraquat. The generation of the superoxide anion through the interaction of oxyhemoglobin with paraquat was suggested by chemiluminescence of luminol. Superoxide dismutase (SOD and catalare inhibited methemoglobin formation. The generation of the superoxide anion is discussed in regard to methemoglobin formation by paraquat.

  10. Challenges in Planet Formation

    CERN Document Server

    Morbidelli, Alessandro


    Over the past two decades, large strides have been made in the field of planet formation. Yet fundamental questions remain. Here we review our state of understanding of five fundamental bottlenecks in planet formation. These are: 1) the structure and evolution of protoplanetary disks; 2) the growth of the first planetesimals; 3) orbital migration driven by interactions between proto-planets and gaseous disk; 4) the origin of the Solar System's orbital architecture; and 5) the relationship between observed super-Earths and our own terrestrial planets. Given our lack of understanding of these issues, even the most successful formation models remain on shaky ground.

  11. Manuel UNIMARC format bibliographique

    CERN Document Server


    This manual is the French translation of the second edition of UNIMARC Manual: bibliographic format published in English in 1994 and completed by 5 updates published from 1996 to 2005. This 5th French edition is composite. It reproduces identically a part of the 4th edition published in 2002 and, for the fields of the format modified in the Update 5, it offers a new more structured presentation. This is a handbook dedicated to French-speaking users of the UNIMARC format for bibliographic descriptions.

  12. Pictorial Formats. Volume 1. Format Development (United States)


    the pilot to help him evaluate when to change course to avoid objects in TF/TA modes. In addition to the projected flight path, there are commanded...TYPESFigMASTER5 Wepo Saus clr ase 00I 16I AI 󈧋TRA- X PI prI MEN p~ll It 62 AIR-TO-GROUND _ - PRGRAM ýRELEASE SELECTIONS _ZY - Figure 58 71T ý Weapon...development should always be done within the context oF a baseline aircraft weapon system. Further studies are needed to simulate and evaluate these formats

  13. Notes on Star Formation

    CERN Document Server

    Krumholz, Mark R


    This book provides an introduction to the field of star formation at a level suitable for graduate students or advanced undergraduates in astronomy or physics. The structure of the book is as follows. The first two chapters begin with a discussion of observational techniques, and the basic phenomenology they reveal. The goal is to familiarize students with the basic techniques that will be used throughout, and to provide a common vocabulary for the rest of the book. The next five chapters provide a similar review of the basic physical processes that are important for star formation. Again, the goal is to provide a basis for what follows. The remaining chapters discuss star formation over a variety of scales, starting with the galactic scale and working down to the scales of individual stars and their disks. The book concludes with a brief discussion of the clearing of disks and the transition to planet formation. The book includes five problem sets, complete with solutions.


    African Journals Online (AJOL)

    has been determined spectrophotometrically for 1:1 complex formation at ... DFT has been extensively used due to their accuracy and low computational cost .... Our input data for analysis of metal-ligand system were absorbance of 50 different.

  15. Collision Induced Galaxy Formation

    CERN Document Server

    Balland, C; Schäffer, R


    We present a semi-analytical model in which galaxy collisions and strong tidal interactions, both in the field and during the collapse phase of groups and clusters help determine galaxy morphology. From a semi-analytical analysis based on simulation results of tidal collisions (Aguilar & White 1985), we propose simple rules for energy exchanges during collisions that allow to discriminate between different Hubble types: efficient collisions result in the disruption of disks and substantial star formation, leading to the formation of elliptical galaxies; inefficient collisions allow a large gas reservoir to survive and form disks. Assuming that galaxy formation proceeds in a Omega_0=1 Cold Dark Matter universe, the model both reproduces a number of observations and makes predictions, among which are the redshifts of formation of the different Hubble types in the field. When the model is normalized to the present day abundance of X-ray clusters, the amount of energy exchange needed to produce elliptical gal...

  16. Halonitromethanes formation in wastewater treatment plant effluents. (United States)

    Song, Hocheol; Addison, Jesse W; Hu, Jia; Karanfil, Tanju


    Halonitromethanes (HNMs) constitute one class of emerging disinfection by-products with high potential health risks. This study investigated the formation and occurrence of HNMs under different disinfection scenarios and the presence of their precursors in municipal wastewater treatment plant (WWTPs) effluents. Formation potential tests performed on WWTP effluents revealed that HNM formation occurred in the order of ozonation-chlorination > ozonation-chloramination > chlorination > chloramination. Ozonation alone did not produce any HNM. Municipal WWTP effluents contained some reactive HNM precursors, possibly the by-products of biological treatment processes and/or some moiety of industry or household origin. No effects of nitrate on the formation of HNMs were observed in this study, and nitrification in WWTPs appears to remove appreciable portion of HNM precursors, especially those reactive to chlorine. UV disinfection using low pressure lamps in municipal WWTPs had negligible impact on HNM formation potential. HNM concentrations in the effluents of selected WWTPs were either non-detectable or less than minimum reporting level, except for one WWTP that gave trichloronitromethane concentrations in the range of 0.9-1.5 microg L(-1). No HNMs were observed in the effluents disinfected with UV radiation. Therefore, it appears the typical wastewater disinfection processes involving chlorination or UV treatment in WWTPs do not produce significant amounts of HNMs.

  17. Coalition Formation under Uncertainty (United States)


    Unfortunately, many current approaches to coalition formation lack provi- sions for uncertainty. This prevents application of coalition formation techniques ...should also include mechanisms and processing techniques that provide stabil- ity, scalability, and, at a minimum, optimality relative to agent beliefs...relocate a piano . For the sake of simplicity, assume payment is divided evenly among the participants in the move (i.e., each mover has the same utility or

  18. PCF File Format.

    Energy Technology Data Exchange (ETDEWEB)

    Thoreson, Gregory G [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)


    PCF files are binary files designed to contain gamma spectra and neutron count rates from radiation sensors. It is the native format for the GAmma Detector Response and Analysis Software (GADRAS) package [1]. It can contain multiple spectra and information about each spectrum such as energy calibration. This document outlines the format of the file that would allow one to write a computer program to parse and write such files.

  19. Densities and Kinematic Viscosities for the Systems Benzene + Methyl Formate, Benzene + Ethyl Formate, Benzene + Propyl Formate, and Benzene + Butyl Formate

    DEFF Research Database (Denmark)

    Emmerling, Uwe; Rasmussen, Peter


    Densities and kinematic viscosities have been measured for the system benzene + methyl formate at 20°C and for the systems benzene + ethyl formate, benzene + propyl formate, and benzene + butyl formate from 20°C to 50°C. The results for the system benzene + methyl formate have been correlated usi...

  20. Towards team formation via automated planning

    NARCIS (Netherlands)

    Muise, Christian; Dignum, Frank; Felli, Paolo; Miller, Tim; Pearce, Adrian R.; Sonenberg, Liz


    Cooperative problem solving involves four key phases: (1) finding potential members to form a team, (2) forming the team, (3) formulating a plan for the team, and (4) executing the plan. We extend recent work on multi-agent epistemic planning and apply it to the problem of team formation in a blocks

  1. Dwarf galaxies : Important clues to galaxy formation

    NARCIS (Netherlands)

    Tolstoy, E


    The smallest dwarf galaxies are the most straight forward objects in which to study star formation processes on a galactic scale. They are typically single cell star forming entities, and as small potentials in orbit around a much larger one they are unlikely to accrete much (if any) extraneous matt

  2. Behavior-Based Formation Control of Swarm Robots

    Directory of Open Access Journals (Sweden)

    Dongdong Xu


    Full Text Available Swarm robotics is a specific research field of multirobotics where a large number of mobile robots are controlled in a coordinated way. Formation control is one of the most challenging goals for the coordination control of swarm robots. In this paper, a behavior-based control design approach is proposed for two kinds of important formation control problems: efficient initial formation and formation control while avoiding obstacles. In this approach, a classification-based searching method for generating large-scale robot formation is presented to reduce the computational complexity and speed up the initial formation process for any desired formation. The behavior-based method is applied for the formation control of swarm robot systems while navigating in an unknown environment with obstacles. Several groups of experimental results demonstrate the success of the proposed approach. These methods have potential applications for various swarm robot systems in both the simulation and the practical environments.

  3. Millimeter Wave Spectrum and Astronomical Search for Vinyl Formate (United States)

    Alonso, E. R.; Kolesniková, L.; Tercero, B.; Cabezas, C.; Alonso, J. L.; Cernicharo, J.; Guillemin, J.-C.


    Previous detections of methyl and ethyl formate make other small substituted formates potential candidates for observation in the interstellar medium. Among them, vinyl formate is one of the simplest unsaturated carboxylic ester. The aim of this work is to provide direct experimental frequencies of the ground vibrational state of vinyl formate in a large spectral range for astrophysical use. The room-temperature rotational spectrum of vinyl formate has been measured from 80 to 360 GHz and analyzed in terms of Watson’s semirigid rotor Hamiltonian. Two thousand six hundred transitions within J = 3-88 and K a = 0-28 were assigned to the most stable conformer of vinyl formate and a new set of spectroscopic constants was accurately determined. Spectral features of vinyl formate were then searched for in Orion KL, Sgr B2(N), B1-b, and TMC-1 molecular clouds. Upper limits to the column density of vinyl formate are provided.

  4. Formation peculiarities of tourism documentation


    Zhezhnych, Pavlo; Soprunyuk, Oksana


    The article describes formation peculiarities of tourism documentation, the role of tourism data consolidation for unified format creation and the the need to use existing software tools to handle tourism information, formation process of tourism documentation is presented.

  5. Situated Formative Feedback

    DEFF Research Database (Denmark)

    Lukassen, Niels Bech; Wahl, Christian; Sorensen, Elsebeth Korsgaard


    This study addresses the conceptual challenge of providing students with good quality feedback to enhance student learning in an online community of practice (COP). The aim of the study is to identify feedback mechanisms in a virtual learning environment (VLE) and to create a full formative...... feedback episode (FFE) through an online dialogue. The paper argues that dialogue is crucial for student learning and that feedback is not only something the teacher gives to the student. Viewing good quality feedback as social, situated, formative, emphasis is put on the establishment of dialogue. We...... refer to this type of feedback as, Situated Formative Feedback (SFF). As a basis for exploring, identifying and discussing relevant aspects of SFF the paper analyses qualitative data from a Moodle dialogue. Data are embedded in the qualitative analytic program Nvivo and are analysed with a system...

  6. Forces in strategy formation

    DEFF Research Database (Denmark)

    Steensen, Elmer Fly


    This chapter proposes that organizational strategy formation should be characterized theoretically as a process that is subject to several interacting forces, rather than represented by separate discrete decisionmodels or theoretic perspectives, as is commonly done in the strategic management...... literature. Based on an extensive review of relevant theory and empirical work in strategic decision-making, organizational change theory, cognitive and social psychology, and strategy processes, seven kinds of ''forces'' - rational, imposed, teleological, learning, political, heuristic, and social...... - are identified as interacting in and having significant influence on the strategy formation process. It is further argued that by applying a holistic ''forces-view'' of the significant and interacting influences on strategy formation, we can better understand the dynamics and challenges in managing the process...

  7. Meningococcal biofilm formation

    DEFF Research Database (Denmark)

    Lappann, M.; Haagensen, Janus Anders Juul; Claus, H.


    We show that in a standardized in vitro flow system unencapsulated variants of genetically diverse lineages of Neisseria meningitidis formed biofilms, that could be maintained for more than 96 h. Biofilm cells were resistant to penicillin, but not to rifampin or ciprofloxacin. For some strains......, microcolony formation within biofilms was observed. Microcolony formation in strain MC58 depended on a functional copy of the pilE gene encoding the pilus subunit pilin, and was associated with twitching of cells. Nevertheless, unpiliated pilE mutants formed biofilms showing that attachment and accumulation......X alleles was identified among genetically diverse meningococcal strains. PilX alleles differed in their propensity to support autoaggregation of cells in suspension, but not in their ability to support microcolony formation within biofilms in the continuous flow system....

  8. Kuiper Binary Object Formation

    CERN Document Server

    Nazzario, R C; Covington, C; Kagan, D; Hyde, T W


    It has been observed that binary Kuiper Belt Objects (KBOs) exist contrary to theoretical expectations. Their creation presents problems to most current models. However, the inclusion of a third body (for example, one of the outer planets) may provide the conditions necessary for the formation of these objects. The presence of a third massive body not only helps to clear the primordial Kuiper Belt but can also result in long lived binary Kuiper belt objects. The gravitational interaction between the KBOs and the third body causes one of four effects; scattering into the Oort cloud, collisions with the growing protoplanets, formation of binary pairs, or creation of a single Kuiper belt object. Additionally, the initial location of the progenitors of the Kuiper belt objects also has a significant effect on binary formation.

  9. Primordial Planet Formation

    CERN Document Server

    Schild, Rudolph E


    Recent spacecraft observations exploring solar system properties impact standard paradigms of the formation of stars, planets and comets. We stress the unexpected cloud of microscopic dust resulting from the DEEP IMPACT mission, and the existence of molten nodules in STARDUST samples. And the theory of star formation does not explain the common occurrence of binary and multiple star systems in the standard gas fragmentation scenario. No current theory of planet formation can explain the iron core of the earth, under oceans of water. These difficulties are avoided in a scenario where the planet mass objects form primordially and are today the baryonic dark matter. They have been detected in quasar microlensing and anomalous quasar radio brightening bursts. The primordial planets often concentrate together to form a star, with residual matter seen in pre-stellar accretion discs around the youngest stars. These primordial planet mass bodies were formed of hydrogen-helium, aggregated in dense clumps of a trillion...

  10. Meningococcal biofilm formation

    DEFF Research Database (Denmark)

    Lappann, M.; Haagensen, Janus Anders Juul; Claus, H.


    We show that in a standardized in vitro flow system unencapsulated variants of genetically diverse lineages of Neisseria meningitidis formed biofilms, that could be maintained for more than 96 h. Biofilm cells were resistant to penicillin, but not to rifampin or ciprofloxacin. For some strains......, microcolony formation within biofilms was observed. Microcolony formation in strain MC58 depended on a functional copy of the pilE gene encoding the pilus subunit pilin, and was associated with twitching of cells. Nevertheless, unpiliated pilE mutants formed biofilms showing that attachment and accumulation......X alleles was identified among genetically diverse meningococcal strains. PilX alleles differed in their propensity to support autoaggregation of cells in suspension, but not in their ability to support microcolony formation within biofilms in the continuous flow system....

  11. Syntactic Formats for Free

    DEFF Research Database (Denmark)

    Klin, Bartek; Sobocinski, Pawel


    A framework of Plotkin and Turi’s, originally aimed at providing an abstract notion of bi-simulation, is modified to cover other operational equivalences and preorders. Combined with bi-algebraic methods, it yields a technique for the derivation of syntactic formats for transition system specific......A framework of Plotkin and Turi’s, originally aimed at providing an abstract notion of bi-simulation, is modified to cover other operational equivalences and preorders. Combined with bi-algebraic methods, it yields a technique for the derivation of syntactic formats for transition system...... specifications which guarantee operational preorders to be precongruences. The technique is applied to the trace preorder, the completed trace pre order and the failures preorder. In the latter two cases, new syntactic formats ensuring precongruence properties are introduced....

  12. The format of things

    DEFF Research Database (Denmark)

    Jørnø, Rasmus Leth

    or surpasses speech and writing. The well from which we draw our design ideas for novel interfaces is therefore needlessly restricted by a format that has outlived its purpose. The objective of the thesis is to dismantle the format of things as well as to sketch out novel paths of inquiry for new interfaces...... ontological biases and epistemological assumptions which, to a great extent, delimit what can be thought about interfaces and shorten the imaginative horizon. The objective of this thesis is to break the hegemony of a particular type of understanding of the world and interfaces, and to make new approaches...

  13. Sensitivity Data File Formats

    Energy Technology Data Exchange (ETDEWEB)

    Rearden, Bradley T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)


    The format of the TSUNAMI-A sensitivity data file produced by SAMS for cases with deterministic transport solutions is given in Table 6.3.A.1. The occurrence of each entry in the data file is followed by an identification of the data contained on each line of the file and the FORTRAN edit descriptor denoting the format of each line. A brief description of each line is also presented. A sample of the TSUNAMI-A data file for the Flattop-25 sample problem is provided in Figure 6.3.A.1. Here, only two profiles out of the 130 computed are shown.

  14. Formation of Saturn's spokes (United States)

    Goertz, C. K.


    The theoretical requirements of the Goertz and Morfill (1983) model of the formation of spokes in the rings of Saturn are analyzed. Consideration is given to model predictions of dust particle size distribution, the optical depth of the spokes, and the radial speed of spoke evolution. It is shown that the electrostatic levitation of singly charged dust particles would be sufficient to cause the spokes to form. The maximum formation time for spokes of more than 10,000 km radial length is estimated to be less than five minutes. Observations of the scattering properties of the spokes showed general agreement with the theoretical calculations.

  15. The formation of stars

    CERN Document Server

    Stahler, Steven W


    This book is a comprehensive treatment of star formation, one of the most active fields of modern astronomy. The reader is guided through the subject in a logically compelling manner. Starting from a general description of stars and interstellar clouds, the authors delineate the earliest phases of stellar evolution. They discuss formation activity not only in the Milky Way, but also in other galaxies, both now and in the remote past. Theory and observation are thoroughly integrated, with the aid of numerous figures and images. In summary, this volume is an invaluable resource, both as a text f

  16. Tea aroma formation

    Directory of Open Access Journals (Sweden)

    Chi-Tang Ho


    Full Text Available Besides water, tea is one of the most popular beverages around the world. The chemical ingredients and biological activities of tea have been summarized recently. The current review summarizes tea aroma compounds and their formation in green, black, and oolong tea. The flavor of tea can be divided into two categories: taste (non-volatile compounds and aroma (volatile compounds. All of these aroma molecules are generated from carotenoids, lipids, glycosides, etc. precursors, and also from Maillard reaction. In the current review, we focus on the formation mechanism of main aromas during the tea manufacturing process.

  17. International Evoked Potentials Symposium

    CERN Document Server


    The past decade has seen great progress in the measurement of evoked potentials in man; a steady increase in our understanding of their charac­ teristics, their origins and their usefulness; and a growing application in the field of clinical diagnosis. The topic is a truly multidisciplinary one. Important research contributions have been made by workers of many different backgrounds and clinical applications span the specialities. This book represents a revised and updated version of the work originally presented at the international evoked potential symposium held in Nottingham 4-6 1978. The Nottingham Symposium provided a forum for a state-of-the-art discussion amongst workers from many different disciplines and from many different countries. For each major topic in the field an expert review set the scene for discussion of current research presentations. This format is retained in the book: the chapters in Part A provide the context in which the research presented in Part B is set. The task of selecting m...

  18. Evaluation of hydrocarbon potential

    Energy Technology Data Exchange (ETDEWEB)

    Cashman, P.H.; Trexler, J.H. Jr. [Univ. of Nevada, Reno, NV (United States)


    Task 8 is responsible for assessing the hydrocarbon potential of the Yucca Mountain vincinity. Our main focus is source rock stratigraphy in the NTS area in southern Nevada. (In addition, Trexler continues to work on a parallel study of source rock stratigraphy in the oil-producing region of east central Nevada, but this work is not funded by Task 8.) As a supplement to the stratigraphic studies, we are studying the geometry and kinematics of deformation at NTS, particularly as these pertain to reconstructing Paleozoic stratigraphy and to predicting the nature of the Late Paleozoic rocks under Yucca Mountain. Our stratigraphic studies continue to support the interpretation that rocks mapped as the {open_quotes}Eleana Formation{close_quotes} are in fact parts of two different Mississippian units. We have made significant progress in determining the basin histories of both units. These place important constraints on regional paleogeographic and tectonic reconstructions. In addition to continued work on the Eleana, we plan to look at the overlying Tippipah Limestone. Preliminary TOC and maturation data indicate that this may be another potential source rock.

  19. Iloprost induces tertiary dentin formation. (United States)

    Limjeerajarus, Chalida Nakalekha; Chanarattanubol, Thichaporn; Trongkij, Panruethai; Rujiwanichkul, Mirantee; Pavasant, Prasit


    Prostacyclin (PGI2), a member of the prostaglandin family, can promote angiogenesis and cell proliferation. In this study, the effect of the application of a PGI2 analog (iloprost) on dentin repair was examined in vitro and in vivo. Iloprost significantly stimulated the expression of vascular endothelial growth factor and osteo-/odontogenic marker messenger RNA in human dental pulp cells (HDPCs) under osteoinductive conditions in vitro. In addition, iloprost enhanced HDPC alkaline phosphatase enzymatic activity and mineral deposition. An in vivo study was performed using a rat molar mechanical pulp exposure model. After 30 days, histologic analysis revealed that there was a dramatic tertiary dentin formation in the iloprost-treated group compared with the calcium hydroxide and the untreated control groups. Furthermore, vascular endothelial growth factor protein expression in dental pulp tissue was increased in the iloprost-treated group as determined by immunohistochemical staining. Taken together, the present study, for the first time, shows that iloprost induces the expression of osteo-/odontogenic markers in vitro and promotes angiogenic factor expression and enhances tertiary dentin formation in vivo. This implies the potential clinical usefulness of iloprost in vital pulp therapy. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  20. Enamel formation and amelogenesis imperfecta. (United States)

    Hu, Jan C-C; Chun, Yong-Hee P; Al Hazzazzi, Turki; Simmer, James P


    Dental enamel is the epithelial-derived hard tissue covering the crowns of teeth. It is the most highly mineralized and hardest tissue in the body. Dental enamel is acellular and has no physiological means of repair outside of the protective and remineralization potential provided by saliva. Enamel is comprised of highly organized hydroxyapatite crystals that form in a defined extracellular space, the contents of which are supplied and regulated by ameloblasts. The entire process is under genetic instruction. The genetic control of amelogenesis is poorly understood, but requires the activities of multiple components that are uniquely important for dental enamel formation. Amelogenesis imperfecta (AI) is a collective designation for the variety of inherited conditions displaying isolated enamel malformations, but the designation is also used to indicate the presence of an enamel phenotype in syndromes. Recently, genetic studies have demonstrated the importance of genes encoding enamel matrix proteins in the etiology of isolated AI. Here we review the essential elements of dental enamel formation and the results of genetic analyses that have identified disease-causing mutations in genes encoding enamel matrix proteins. In addition, we provide a fresh perspective on the roles matrix proteins play in catalyzing the biomineralization of dental enamel.

  1. Radical formation by heavy metals

    Energy Technology Data Exchange (ETDEWEB)

    Beuter, W.


    Certain reduced heavy metal ions can convert oxygen to a ''reactive oxygen species'' by donation of an electron. The reactive oxygen then attacks structures susceptible to oxidation, in particular unsaturated fatty acids, and peroxidizes them in a radical reaction. This process is inhibited by the presence of vitamin E and by other means. Peroxidized lipids decay forming free radicals in the process which themselves can peroxidise neighbouring lipids in a radical chain reaction. This decay is, moreover, catalysed by reduced heavy metal ions but on the other hand retarded by selenium-containing glutathione peroxidase. Radical formation by heavy metals is considerably involved in (i) the production of parenteral iron poisoning of the piglet (ii) haemolytic crisis occurring in ruminants through chronic copper poisoning (iii) the production of lead poisoning in ruminants and other animals. These types of poisonings are made worse by a deficiency of vitamin E and/or selenium. Factors which increase the bio-availability of the free heavy metal ion or reduce the redox potential thereof can aid radical formation as well as factors which lead to a reduction of the heavy metal ion e.g. cysteine, ascorbic acid or glucose.

  2. Formation of $\\phi$ mesic nuclei

    CERN Document Server

    Yamagata-Sekihara, J; Vacas, M J Vicente; Hirenzaki, S


    We study the structure and formation of the $\\phi$ mesic nuclei to investigate the in-medium modification of the $\\phi$-meson spectral function at finite density. We consider (${\\bar p},\\phi$), ($\\gamma,p$) and ($\\pi^-,n$) reactions to produce a $\\phi$-meson inside the nucleus and evaluate the effects of its medium modifications to the reaction cross sections. We also estimate the consequences of the uncertainties of the ${\\bar K}$ selfenergy in medium to the $\\phi$-nucleus interaction. We find that it may be possible to see a peak structure in the reaction spectra for the strong attractive potential cases. On the other hand, for strong absorptive interaction cases with relatively weak attractions, it is very difficult to observe clear peaks and we may need to know the spectrum shape in a wide energy region to deduce the properties of $\\phi$.

  3. Shape formation algorithm



    This project concerns the implementation of a decentralized algorithm for shape formation. The first idea was to test this algorithm with a swarm of autonomous drones but, due to the lack of time and the complexity of the project, the work was just developed in 2D and in simulation.

  4. Reference Citation Format

    Institute of Scientific and Technical Information of China (English)


    <正>The format for citations in text and for bibliographic references follows the Publication Manual of the American Psychological Association(5thEd.,2001)and GB/T 7714-2005.The citation of printed word should be ordered in number as it appears in the text of the submitted

  5. PAHs and star formation

    NARCIS (Netherlands)

    Tielens, AGGM; Peeters, E; Bakes, ELO; Spoon, HWW; Hony, S; Johnstone, D; Adams, FC; Lin, DNC; Neufeld, DA; Ostriker, EC


    Strong IR emission features at 3.3, 6.2, 7.7, 8.6, and 11.2 mum are a common characteristic of regions of massive star formation. These features are carried by large (similar to 50 C-atom) Polycyclic Aromatic Hydrocarbon molecules which are pumped by the strong FUV photon flux from these stars. Thes

  6. BISAC Variable Format. (United States)

    Information Technology and Libraries, 1983


    Presents revision of Book Industry Systems Advisory Committee (BISAC) format designed specifically for electronic transmission of purchase orders for monograph or series titles combining fixed and variable length data fields which was approved in January 1983. Special characters, sample address descriptions, summary of fixed records, glossary, and…

  7. Kepler Planet Formation (United States)

    Lissauer, Jack J.


    Kepler has vastly increased our knowledge of planets and planetary systems located close to stars. The new data shows surprising results for planetary abundances, planetary spacings and the distribution of planets on a mass-radius diagram. The implications of these results for theories of planet formation will be discussed.