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Sample records for petr nemeek alena

  1. Cross-Cultural Adaptation and Validation of the Spanish Version of the Performance Enhancement Attitude Scale (Petróczi, 2002)

    PubMed Central

    Morente-Sánchez, Jaime; Femia-Marzo, Pedro; Zabala, Mikel

    2014-01-01

    The aim of the present study was to cross-culturally adapt and validate the Spanish version of the Performance Enhancement Attitude Scale (PEAS). A cross-sectional multi-sample survey with 17 independent datasets was carried out. Cross-cultural adaptation of the PEAS into Spanish was conducted through forward/backward translations, consensus panels and comparative analyses of known-groups to establish evidence for its reliability and validity. Weighted Kappa coefficients with quadratic weighting were used to assess the reliability of each item, with Cronbach’s internal consistency coefficients for overall scale’s reliability and Spearman’s correlation coefficient for test–retest reliability over a one-week period. Confirmatory factor analysis (CFA) was performed to assess the scale’s structure. Differences between self-admitted doping users and non-users were analysed to verify the PEAS’ construct validity in 8 datasets. Spearman’s correlation coefficient was also used to assess the relationships between the PEAS and self-esteem, self-efficacy and perceived descriptive norm to establish convergent validity. The scale showed satisfactory levels of internal consistency (α = 0.71–0.85), reliability of each item (Kappa values range 0.34-0.64) and temporal stability (r = 0.818; p < 0.001). CFA showed acceptable fit (RMSEA <0.08, mean RMSEA = 0.055; χ2/df < 3, mean χ2/df = 1.89) for all but one samples. As expected, self-admitted doping users showed more positive attitude toward doping than non-users. Significant and strong negative relationship was found between PEAS and self-efficacy; weak negative correlation with self-esteem and and positive correlation with perceived descriptive norm. The Spanish version of PEAS showed satisfactory psychometric properties. Considerations for application and improvement are outlined. Key points First study that crosses culturally adapted the PEAS to the Spanish language. The Spanish version of PEAS has satisfactory psychometric properties. Users scored higher than non-users indicating a satisfactory construct validity. Significant positive correlation was found between PEAS and projected use. Significant negative correlation between PEAS and self-esteem and self-efficacy. PMID:24790501

  2. Coulombic dragging of molecular assemblies on nanotubes

    NASA Astrophysics Data System (ADS)

    Kral, Petr; Sint, Kyaw; Wang, Boyang

    2009-03-01

    We show by molecular dynamics simulations that polar molecules, ions and their assemblies could be Coulombically dragged on the surfaces of single-wall carbon and boron-nitride nanotubes by ionic solutions or individual ions moving inside the nanotubes [1,2]. We also briefly discuss highly selective ionic sieves based on graphene monolayers with nanopores [3]. These phenomena could be applied in molecular delivery, separation and desalination.[3pt] [1] Boyang Wang and Petr Kral, JACS 128, 15984 (2006). [0pt] [2] Boyang Wang and Petr Kral, Phys. Rev. Lett. 101, 046103 (2008). [0pt] [3] Kyaw Sint, Boyang Wang and Petr Kral, JACS, ASAP (2008).

  3. Trends in biolubricant development

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biolubricants are those formulated from components that are derived from renewable raw materials. This distinguishes biolubricants from the majority of lubricants currently in the global market whose ingredients are derived from petroleum. Biolubricants also are easily biodegradable compared to petr...

  4. Type specimens of centipedes (Myriapoda, Chilopoda) in the National Museum, Prague (Czech Republic)

    PubMed Central

    Dolejš, Petr

    2015-01-01

    Abstract The centipede collection in the National Museum in Prague contains type material of 16 taxa (14 species and two subspecies), of which 15 were described by Luděk J. Dobroruka and one by Karl W. Verhoeff: Allothereua wilsonae Dobroruka, 1979; Chinobius alenae Dobroruka, 1980; Lithobius corrigendus Dobroruka, 1988; Lithobius creticus Dobroruka, 1977; Lithobius erythrocephalus mohelensis Dobroruka, 1959; Lithobius evae Dobroruka, 1958; Lithobius magurensis Dobroruka, 1971; Lithobius purkynei Dobroruka, 1957; Lithobius tatricus Dobroruka, 1958; Lithobius tatricus monounguis Dobroruka, 1958; Monotarsobius homolaci Dobroruka, 1971; Monotarsobius krali Dobroruka, 1979; Pachymerium dilottiae Dobroruka, 1976; Pachymerium hanzaki Dobroruka, 1976; Scolopendra aztecorum Verhoeff, 1934 and Strigamia olympica Dobroruka, 1977. Of these 16 taxa, five were described from the Czech Republic, three from Slovakia and eight from other countries (Greece, Iraq, Kyrgyzstan, Mexico, Nepal, Russia and Uzbekistan). The eight taxa described from the Czech and Slovak Republics are now considered as junior synonyms but the eight taxa described from the other countries are still valid. PMID:26257531

  5. Carbon-based ion and molecular channels

    NASA Astrophysics Data System (ADS)

    Sint, Kyaw; Wang, Boyang; Kral, Petr

    2008-03-01

    We design ion and molecular channels based on layered carboneous materials, with chemically-functionalized pore entrances. Our molecular dynamics simulations demonstrate that these ultra-narrow pores, with diameters around 1 nm, are highly selective to the charges and sizes of the passing (Na^+ and Cl^-) ions and short alkanes. We demonstrate that the molecular flows through these pores can be easily controlled by electrical and mechanical means. These artificial pores could be integrated in fluidic nanodevices and lab-on-a-chip techniques with numerous potential applications. [1] Kyaw Sint, Boyang Wang and Petr Kral, submitted. [2] Boyang Wang and Petr Kral, JACS 128, 15984 (2006).

  6. On rational R-matrices with adjoint SU(n) symmetry

    NASA Astrophysics Data System (ADS)

    Stronks, Laurens; van de Leur, Johan; Schuricht, Dirk

    2016-11-01

    Using the representation theory of Yangians we construct the rational R-matrix which takes values in the adjoint representation of SU(n). From this we derive an integrable SU(n) spin chain with lattice spins transforming under the adjoint representation. However, the resulting Hamiltonian is found to be non-Hermitian. Dedicated to the memory of Petr Petrovich Kulish.

  7. Preparing Doctoral Candidates for the Viva: Issues for Students and Supervisors

    ERIC Educational Resources Information Center

    Watts, Jacqueline H.

    2012-01-01

    The PhD viva has been described as mysterious (Burnham 1994; Morley et al. 2002), unpredictable (Rugg & Petre 2004) and potentially frightening for students (Delamont et al. 2004), with its form and duration a function of the predilections of individual examiners as well as a function of differences across disciplines. Despite its myriad…

  8. DNA adducts induced by in vitro activation of diesel and biodiesel exhaust extracts

    EPA Science Inventory

    The abstract reports the results of studies assessing the relative DNA damage potential of extracts of exhaust particles resulting from the combustion of petroleum diesel, biodiesel, and petroleum diesel-biodiesel blends. Results indicate that the commercially available B20 petr...

  9. Photons and magnetization

    NASA Astrophysics Data System (ADS)

    2013-06-01

    Magnets are often electrically activated, but recent research has demonstrated various schemes that can control magnetization using light and photocarriers. Nature Photonics spoke to Petr Němec and Tomas Jungwirth about their recent work on a polarization-independent optical-torque approach.

  10. An Exploration of the Roles of Communication Apprehension, Online Technology Self-Efficacy, and Retention in an Online Public Speaking Course

    ERIC Educational Resources Information Center

    Stout, Carla Sulivant

    2012-01-01

    Although the growth rate of online learning continues to increase, online courses are yielding higher attrition rates compared to traditional learning courses (Carswell, Thomas, Petre, Price, & Richards, 2000; Clark & Jones, 2001; Nash, 2005; Park & Choi, 2009). The literature has previously linked online technology self-efficacy and…

  11. Improving 18F-Fluoro-D-Glucose-Positron Emission Tomography/Computed Tomography Imaging in Alzheimer's Disease Studies

    PubMed Central

    Knešaurek, Karin

    2015-01-01

    The goal was to improve Alzheimer's 2-deoxy-2-18F-fluoro-D-glucose (18F FDG)-positron emission tomography (PET)/computed tomography (CT) imaging through application of a novel, hybrid Fourier-wavelet windowed Fourier transform (WFT) restoration technique, in order to provide earlier and more accurate clinical results. General Electric Medical Systems downward-looking sonar PET/CT 16 slice system was used to acquire studies. Patient data were acquired according the Alzheimer's disease Neuroimaging Initiative (ADNI) protocol. Here, we implemented Fourier-wavelet regularized restoration, with a Butterworth low-pass filter, order n = 6 and a cut-off frequency f = 0.35 cycles/pixel and wavelet (Daubechies, order 2) noise suppression. The original (PET-O) and restored (PET-R) ADNI subject PET images were compared using the Alzheimer's discrimination analysis by dedicated software. Forty-two PET/CT scans were used in the study. They were performed on eleven ADNI subjects at intervals of approximately 6 months. The final clinical diagnosis was used as a gold standard. For three subjects, the final clinical diagnosis was mild cognitive impairment and those 13 PET/CT studies were not included in the final comparison, as the result was considered as inconclusive. Using the reminding 29 PET/CT studies (23 AD and 6 normal), the sensitivity and specificity of the PET-O and PET-R were calculated. The sensitivity was 0.65 and 0.96 for PET-O and PET-R, respectively, and the specificity was 0.67 and 0.50 for PET-O and PET-R. The accuracy was 0.66 and 0.86 for PET-O and PET-R, respectively. The results of the study demonstrated that the accuracy of three-dimensional brain F-18 FDG PET images was significantly improved by Fourier-wavelet restoration filtering. PMID:26420987

  12. Improving (18)F-Fluoro-D-Glucose-Positron Emission Tomography/Computed Tomography Imaging in Alzheimer's Disease Studies.

    PubMed

    Knešaurek, Karin

    2015-01-01

    The goal was to improve Alzheimer's 2-deoxy-2-(18)F-fluoro-D-glucose ((18)F FDG)-positron emission tomography (PET)/computed tomography (CT) imaging through application of a novel, hybrid Fourier-wavelet windowed Fourier transform (WFT) restoration technique, in order to provide earlier and more accurate clinical results. General Electric Medical Systems downward-looking sonar PET/CT 16 slice system was used to acquire studies. Patient data were acquired according the Alzheimer's disease Neuroimaging Initiative (ADNI) protocol. Here, we implemented Fourier-wavelet regularized restoration, with a Butterworth low-pass filter, order n = 6 and a cut-off frequency f = 0.35 cycles/pixel and wavelet (Daubechies, order 2) noise suppression. The original (PET-O) and restored (PET-R) ADNI subject PET images were compared using the Alzheimer's discrimination analysis by dedicated software. Forty-two PET/CT scans were used in the study. They were performed on eleven ADNI subjects at intervals of approximately 6 months. The final clinical diagnosis was used as a gold standard. For three subjects, the final clinical diagnosis was mild cognitive impairment and those 13 PET/CT studies were not included in the final comparison, as the result was considered as inconclusive. Using the reminding 29 PET/CT studies (23 AD and 6 normal), the sensitivity and specificity of the PET-O and PET-R were calculated. The sensitivity was 0.65 and 0.96 for PET-O and PET-R, respectively, and the specificity was 0.67 and 0.50 for PET-O and PET-R. The accuracy was 0.66 and 0.86 for PET-O and PET-R, respectively. The results of the study demonstrated that the accuracy of three-dimensional brain F-18 FDG PET images was significantly improved by Fourier-wavelet restoration filtering.

  13. Exosphere generation of the Moon investigated through a high-energy neutral detector

    NASA Astrophysics Data System (ADS)

    Milillo, Anna; Mangano, Valeria; Mura, Alessandro; Orsini, Stefano; de Angelis, Elisabetta; di Lellis, Andrea M.; Massetti, Stefano; Plainaki, Christina; Rispoli, Rosanna; Selci, Stefano; Vertolli, Nello

    2011-10-01

    Observation of the lunar exosphere is a tool for remote sensing of the surface properties. The sources of this exosphere are related to the interactions of the lunar surface with the solar radiation, with the solar wind or Earth's magnetospheric plasma, and with the interplanetary dust and meteorites. In fact, the exospheric particles are continuously created and subsequently lost in the interplanetary space, photo-ionized or re-adsorbed by the surface. Eventually, the estimation of the surface composition is not possible without the knowledge of the active release mechanisms. The relative weight of the different release processes of the various atoms, ions and molecules from the surface is still an open debate. Investigation of the Moon's release processes and interaction with the near-Earth environment is of crucial importance for both determining the relative process release contribution and understanding the surface evolution of other airless bodies, like Mercury and the giant planets' moons. In this work, an attempt to analyze the processes that take place on the surface of these small airless bodies, as a result of their exposure to the space environment, has been realized by means of the MonteCarlo Environment Simulation Tool (EST), applied to the Moon. The model results show that the different release processes can be identified by analysing the exospheric energy distribution. Finally, the instrument concept of the "Analizzatore Lunare di ENA" (ALENA), part of the MAGIA payload and specifically designed for detecting the high-energy particles released from the lunar surface is presented.

  14. Plutonium Chemistry in the UREX+ Separation Processes

    SciTech Connect

    ALena Paulenova; George F. Vandegrift, III; Kenneth R. Czerwinski

    2009-10-01

    The project "Plutonium Chemistry in the UREX+ Separation Processes” is led by Dr. Alena Paulenova of Oregon State University under collaboration with Dr. George Vandegrift of ANL and Dr. Ken Czerwinski of the University of Nevada at Las Vegas. The objective of the project is to examine the chemical speciation of plutonium in UREX+ (uranium/tributylphosphate) extraction processes for advanced fuel technology. Researchers will analyze the change in speciation using existing thermodynamics and kinetic computer codes to examine the speciation of plutonium in aqueous and organic phases. They will examine the different oxidation states of plutonium to find the relative distribution between the aqueous and organic phases under various conditions such as different concentrations of nitric acid, total nitrates, or actinide ions. They will also utilize techniques such as X-ray absorbance spectroscopy and small-angle neutron scattering for determining plutonium and uranium speciation in all separation stages. The project started in April 2005 and is scheduled for completion in March 2008.

  15. Selenium content in sulfide ores from the Chalkidiki peninsula, Greece.

    PubMed

    Nicolaidou, A E

    1998-01-01

    Selenium (Se) was assessed in galena, sphalerite, and pyrite samples. These are components of mixed sulfide ores from the Olympias and Madem Lakkos-Mavres Petres deposits and the Skouries porphyry-copper deposit. We used atomic absorption spectroscopy (AAS) with a hydride generator system. The highest concentration of Se (516 ppm) was found in the fine-grained galena at the -135 level of the Olympias deposits. In the Madem Lakkos-Mavres Petres deposit, the highest concentration of Se (33 ppm) was found in the pyrites of the level 30. The concentration of Se in the arsenopyrites and chalcopyrites is lower than the detection limit of the analytical method (< 100 ppb). The concentrated chalcopyrite from the porphyry copper deposit at Skouries exhibits a significant Se content (average 200 ppm) in contrast to the chalcopyrite from the Olympias and the Madem Lakkos-Mavres Petres. Variations in the Se content of the sulfide minerals studied could be caused by redox-pH and/or temperature conditions, as well as by the difference in crystal structure. The Se found in the areas studied may positively affect the environment. Sulfide minerals are oxidized by microorganisms, infiltrate in the soil-water in the form of selenate or selenite ion, and directly or indirectly influence the human organism. PMID:9726790

  16. Selenium content in sulfide ores from the Chalkidiki peninsula, Greece.

    PubMed

    Nicolaidou, A E

    1998-01-01

    Selenium (Se) was assessed in galena, sphalerite, and pyrite samples. These are components of mixed sulfide ores from the Olympias and Madem Lakkos-Mavres Petres deposits and the Skouries porphyry-copper deposit. We used atomic absorption spectroscopy (AAS) with a hydride generator system. The highest concentration of Se (516 ppm) was found in the fine-grained galena at the -135 level of the Olympias deposits. In the Madem Lakkos-Mavres Petres deposit, the highest concentration of Se (33 ppm) was found in the pyrites of the level 30. The concentration of Se in the arsenopyrites and chalcopyrites is lower than the detection limit of the analytical method (< 100 ppb). The concentrated chalcopyrite from the porphyry copper deposit at Skouries exhibits a significant Se content (average 200 ppm) in contrast to the chalcopyrite from the Olympias and the Madem Lakkos-Mavres Petres. Variations in the Se content of the sulfide minerals studied could be caused by redox-pH and/or temperature conditions, as well as by the difference in crystal structure. The Se found in the areas studied may positively affect the environment. Sulfide minerals are oxidized by microorganisms, infiltrate in the soil-water in the form of selenate or selenite ion, and directly or indirectly influence the human organism.

  17. Monitoring of full-depth avalanches contaminated by soil and rocks - their origin and consequences, (Krkonose/Karkonosze Mts.- High Sudetes)

    NASA Astrophysics Data System (ADS)

    Kocianova, M.

    2009-04-01

    Monitoring of full-depth avalanches contaminated by soil and rocks - their origin and consequences, (Krkonose/Karkonosze Mts.- High Sudetes) Milena Kocianova Valerian Spusta, Irena Spatenkova, Alena Tondrova, Igor Jan Dvorak, Vlastimil Pilous Krkonoše National Park Administration, Dobrovskeho 3, 543 01 Vrchlabi, Czech republic Monitoring of snow avalanches is provided in Czech part of the Krkonose/Karkonosze Mountains since the winter season 1961/62. The full-depth avalanches contaminated by soil and rocks represent about 4% of the monitored number. There are six bigger avalanches of this type recorded during last 10 years. The areas of snutched weathering mantles reached at about 3000 - 23 000 m2 per individual avalanche track. In deposit zones the areas from 2600 to 18700 m2 were covered by soil, sods and small rock fragments whose volume ranged from about 130 to 880 m3 per individual avalanche track. The volume of large rock fragments in one concrete track was counted up to 144 m3. The great influence of full depth avalanches on relief and slope development is evident. Based on monitoring the speed of snutched areas overgrowing by vegetation and on comparison of space design of plant communities out off and on the avalanche tracks respectively, it would be possible to estimate the period of such bigger events. Very important thing is that four avalanche events were triggered by water, which infiltrated the base of snowpack within upper or central parts of avalanche slopes. Water origin was probably either a) in mires on adjacent summit plateau (ground water flown on inclined bedrock layers to the avalanche slopes) and b) in thawing water of snow patches situated on the cryoplanation terraces above the avalanche slopes. More detailed study of these phenomena is needed in the future.

  18. "Landslide at sunuapa 401 (hydrocarbon exploration well). Risk reduction by mitigation measures: drainage, piles barrier and anchorages system, shotcrete and reforestation, Chiapas, México".

    NASA Astrophysics Data System (ADS)

    Cuanalo, Oscar; Polanco, Gabriel; Rivera, Julio

    2013-04-01

    We report the case of a landslide of hydrocarbon exploration well "Sunuapa 401" located in Chiapas, Mexico. First were identified the determinants and triggers factors (morphology, geology, rain, seismic and volcanic activity, human activity, etc); second we assessed the threat, vulnerability and risk from geotechnical stability analysis (safety factor and critical failure surface); third, by using the methodology of valuation factors, stabilization processes were selected and designed, and finally they were built by Petróleos Mexicanos, in order to avoid a disaster (environmental, ecological and social). These construction processes included drainage elements, flattening and benching of slopes, piles barrier and anchors, shotcrete and reforestation.

  19. Erratum to "Predicting sulphur and nitrogen deposition using a simple statistical method" [Atmos. Environ. 140 (2016) 456-468

    NASA Astrophysics Data System (ADS)

    Oulehle, Filip; Kopáček, Jiří; Chuman, Tomáš; Černohous, Vladimír; Hůnová, Iva; Hruška, Jakub; Krám, Pavel; Lachmanová, Zora; Navrátil, Tomáš; Štěpánek, Petr; Tesař, Miroslav; Evans, Christopher D.

    2016-10-01

    The Journal regrets that the author's names were tagged incorrectly resulting in author forenames appearing as surnames. The correct author names are: Filip Oulehle, Jiří Kopáček, Tomáš Chuman, Vladimír Černohous, Iva Hůnová, Jakub Hruška, Pavel Krám, Zora Lachmanová, Tomáš Navrátil, Petr Štěpánek, Miroslav Tesař, Christopher D. Evans. The Journal would like to apologise for any inconvenience caused.

  20. Conjoined twins: scientific cinema and Pavlovian physiology.

    PubMed

    Krementsov, Nikolai

    2015-01-01

    Through the lens of a 1957 documentary film, "Neural and humoral factors in the regulation of bodily functions (research on conjoined twins)," produced by the USSR Academy of Medical Sciences, this essay traces the entwined histories of Soviet physiology, studies of conjoined twins and scientific cinema. It examines the role of Ivan Pavlov and his students, including Leonid Voskresenkii, Dmitrii Fursikov and Petr Anokhin, in the development of "scientific film" as a particular cinematographic genre in Soviet Russia and explores numerous puzzles hidden behind the film's striking visuals.

  1. Conjoined twins: scientific cinema and Pavlovian physiology.

    PubMed

    Krementsov, Nikolai

    2015-01-01

    Through the lens of a 1957 documentary film, "Neural and humoral factors in the regulation of bodily functions (research on conjoined twins)," produced by the USSR Academy of Medical Sciences, this essay traces the entwined histories of Soviet physiology, studies of conjoined twins and scientific cinema. It examines the role of Ivan Pavlov and his students, including Leonid Voskresenkii, Dmitrii Fursikov and Petr Anokhin, in the development of "scientific film" as a particular cinematographic genre in Soviet Russia and explores numerous puzzles hidden behind the film's striking visuals. PMID:26601729

  2. [Study of the structure of the professional autonomy in nursing's social representation].

    PubMed

    Gomes, Antonio Marcos Tosoli; de Oliveira, Denize Cristina

    2005-06-01

    This study analyzed the social representation of the structure of the professional autonomy in nursing built up by nurses in the city of Petrópolis. The referential adopted was the Theory of Social Representations, in accordance to the structural approach. Data collection was carried out using the technique of free evocation from the term "profes-sional autonomy" among 83 nurses, of which 42 worked at the basic services and 41 in hospitals. Data was analyzed through the construction of the four-digit chart. The results indicate as possible central elements the terms "knowledge", "achievement" and "responsibility", and as peripheral elements "limited", "little" and "utopia".

  3. Zerovalent iron and iron(VI): Effective means for the removal of psychoactive pharmaceuticals and illicit drugs from wastewaters.

    PubMed

    Mackuľak, Tomáš; Birošová, Lucia; Bodík, Igor; Grabic, Roman; Takáčová, Alžbeta; Smolinská, Miroslava; Hanusová, Anna; Híveš, Ján; Gál, Miroslav

    2016-01-01

    Herein we report the analysis of 27 selected psychoactive compounds found in the wastewater of the largest suburb in the eastern part of Central Europe Bratislava—Petržalka, Slovakia. Thirteen of them (MDMA, methamphetamine, amphetamine, THC-COOH, benzoylecgonine, codeine, tramadol, venlafaxine, oxazepam, citalopram, methadone, EDDP, cocaine) were found in concentrations above 30 ng/L. These compoundswere selected for further monitoring. The possibility of complete degradation of these 13 substances by zerovalent iron and iron(VI) was studied in thewastewater from the Petržalka treatment plant. During the week the concentration of themajority of the studied compounds inwastewaterwas stable. Concentrations of MDMA, cocaine, tramadol, and oxazepam reached significantly higher levels during the weekend.Only about 10% removal efficiency for tramadol, venlafaxine, oxazepam, MDMA, citalopram, methadone, and EDDP was observed at the treatment plant. In contrast, methamphetamine, amphetamine, and codeine were removed with 68%, 83%, and 53% efficiency, respectively. The degradation of synthetic drugs (methamphetamine, cocaine, MDMA) in wastewater is limited, while cannabis (of natural biological origin) is degradedwith efficiency greater than 90%. After utilization of the Fenton reaction, its modification, and use of ferrate(VI), a high efficiency of eliminating all of these substances to values below the limit of detection was achieved. PMID:26376114

  4. Radiation forces on small particles in the Solar System: A re-consideration

    NASA Astrophysics Data System (ADS)

    Burns, Joseph A.; Lamy, Philippe L.; Soter, Steven

    2014-04-01

    We respond to Klačka et al. (Klačka, J., Petržala, J., Pástor, P., Kómar, L. [2014]. Icarus, this issue, http://dx.doi.org/10.1016/j.icarus.2012.06.044.), who have criticized many previous derivations of the acceleration experienced by a spherical interplanetary particle owing to the Sun’s radiation. Much of their criticism arises from differences in semantics and notation as well as effects that are unimportant at Solar System speeds. Accordingly, in the appropriate limiting cases, most published expressions for the radiation forces, such as that found in Burns et al. (Burns, J.A., Lamy, P.L., Soter, S. [1979]. Icarus 40 1-48), are correct and duplicate the results of Klačka et al. (Klačka, J., Petržala, J., Pástor, P., Kómar, L. [2014]. Icarus, this issue, http://dx.doi.org/10.1016/j.icarus.2012.06.044).

  5. Still red light for red light cameras? An update.

    PubMed

    Høye, Alena

    2013-06-01

    The present study has replicated the results from a previous meta-analysis by Erke (2009) [Erke, A., 2009. Red light for red-light cameras? A meta-analysis of the effects of red-light cameras on crashes. Accident Analysis & Prevention 41 (5), 897-905.] based on a larger sample of RLC-studies, and provides answers to the criticisms that were raised by Lund et al. (2009) [Lund, A.K., Kyrychenko, S.Y., Retting, R.A., 2009. Caution: a comment on Alena Erke's red light for red-light cameras? A meta-analysis of the effects of red-light cameras on crashes. Accident Analysis and Prevention 41, 895-896.] against the previous meta-analysis. The addition of recent studies to the meta-analysis and a more thorough investigation of potential moderator variables lead to a slight improvement of the estimated effects of RLC in the previous meta-analysis. The present study found a non-significant increase of all crashes by 6% and a non-significant decrease of all injury crashes by 13%. Right-angle collisions were found to decrease by 13% and rear-end collisions were found to increase by 39%. For right-angle injury collisions a decrease by 33% was found and for rear-end injury collisions a smaller increase was found (+19%). The effects of RLC are likely to be more favorable when RLC-warning signs are set up at main entrances to areas with RLC enforcement than when each RLC-intersection is signposted. The effects of RLC may become more favorable over time, this could however not be investigated empirically. Several results indicate that spillover effects may occur for right-angle collisions, but most likely not for rear-end and other crashes. If spillover effects do not occur for rear-end crashes, which increase at RLC intersection, this would be a positive result for RLC. However, the results seem to be affected to some degree by publication bias and the effects may therefore be somewhat less favorable than indicated by the results from meta-analysis.

  6. Atmospheric concentrations and loadings of organochlorine pesticides and polychlorinated biphenyls in the Canadian Great Lakes Basin (GLB): Spatial and temporal analysis (1992-2012).

    PubMed

    Shunthirasingham, Chubashini; Gawor, Anya; Hung, Hayley; Brice, Kenneth A; Su, Ky; Alexandrou, Nick; Dryfhout-Clark, Helena; Backus, Sean; Sverko, Ed; Shin, Cecilia; Park, Richard; Noronha, Ronald

    2016-10-01

    Long-term air monitoring data for POPs are required to determine the effectiveness of source reduction measures and factors controlling air concentrations. Air samples were collected between 1992 and 2012 at three sites with different geographical characteristics (Burnt Island, Egbert and Point Petre) in the Canadian Great Lakes Basin (GLB) using high-volume samplers and analyzed for organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs). Spatial and temporal trends of gas-phase concentrations of OCPs, selected PCB congeners and ƩPCBs (84 congeners) were assessed. Egbert had the highest concentrations of some OCPs due to historical [dichlorodiphenyltrichloroethanes (DDTs), dieldrin, γ-hexachlorocyclohexane (γ-HCH)] and current (endosulfan) applications of these pesticides in the surrounding agricultural cropland. This shows that agricultural areas are a source of OCPs to the GLB. High o,p'-/p,p'-DDT ratios were determined and an increasing trend was observed at Point Petre and Burnt Island up to 2004; indicating that the GLB is influenced by dicofol-type DDT sources, which have higher o,p'-/p,p'-DDT ratios than technical DDT. Atmospheric PCB concentrations at Egbert and Point Petre are higher than those measured at Burnt Island, likely due to urban influence and greater populations. Loadings calculations suggest that the atmosphere is a source of α-endosulfan and p,p'-DDT to the lakes and the opposite is true for p,p'-DDE. Long-term decreasing trends were observed for both OCPs and PCBs; consistent with control measures implemented in North America. Atmospheric PCB concentrations are decreasing relatively slowly, with halflives in the range of 9-39 years. Chlordane, α-endosulfan, β-endosulfan, dieldrin, and DDT-related substances showed halflives in the range of 7-13 years. α-HCH and γ-HCH were decreasing rapidly in air, with halflives of 5 years. Long-term declining trends of PCBs and OCPs suggest that regulatory efforts to reduce emissions

  7. Soil moisture trends in the Czech Republic between 1961 and 2012

    NASA Astrophysics Data System (ADS)

    Hlavinka, Petr; Trnka, Miroslav; Brázdil, Rudolf; Možný, Martin; Štěpánek, Petr; Dobrovolný, Petr; Zahradníček, Pavel; Balek, Jan; Semerádová, Daniela; Dubrovský, Martin; Eitzinger, Josef; Wardlow, Brian; Svoboda, Mark; Hayes, Michael; Žalud, Zdeněk

    2015-04-01

    Focused on Drought Research" (no. OP VK CZ.1.07/2.3.00/20.0248) and KONTAKT LH110010 helped plan and execute this study. Petr Hlavinka and Michael Hayes were supported by project "Partnership in Climate Research and Adaptation Strategies" (no. CZ.1.07/2.4.00/31.0056), Rudolf Brazdil and Petr Dobrovolny by projects of the Grant Agency of the Czech Republic (P209/11/0956 and 13-04291S/P209, respectively), and Petr Štěpanek and Martin Možny by project of the National Agency for Agricultural Research no. QI91C054.

  8. A source of PCB contamination in modified high-volume air samplers

    SciTech Connect

    Basu, I.; O'Dell, J.M.; Arnold, K.; Hites, R.A.

    2000-02-01

    Modified Anderson High Volume (Hi-Vol) air samplers are widely used for the collection of semi-volatile organic compounds (such as PCBs) from air. The foam gasket near the main air flow path in these samplers can become contaminated with PCBs if the sampler or the gasket is stored at a location with high indoor air PCB levels. Once the gasket is contaminated, it releases PCBs back into the air stream during sampling, and as a result, incorrectly high air PCB concentrations are measured. This paper presents data demonstrating this contamination problem using measurements from two Integrated Atmospheric Deposition Network sites: one at Sleeping Bear Dunes on Lake Michigan and the other at Point Petre on Lake Ontario. The authors recommend that these gaskets be replaced by Teflon tape and that the storage history of each sampler be carefully tracked.

  9. Experiences accessing public funds for hydrocarbons research and technological development in Mexico

    NASA Astrophysics Data System (ADS)

    Suro-Pérez, V.

    2013-05-01

    The Mexican Petroleum Institute (IMP) is a public facility oriented to research and technological development for the national petroleum industry. Its investment plan and operating expenses come, mainly, from selling engineering services to Petróleos Mexicanos. Its projects include upstream and downstream aspects, and the generated income together with public funds support research projects. These funds were approved since 2005, and widened in 2008 thanks to the so called Energy Reform. Until now, more than 50 projects have been funded, and this presentation shows the process to select, to approve, to fund and to ensure the results promised in the original proposal. It is shown that technical sanction of every particular project is essential to succeed, jointly with a structure of real technical pairs to advise during project development. Likewise, the mechanisms for accessing the funds are described, and simple suggestions are made to improve administrative efficiency.

  10. Acceptance and commitment therapy-based self-management versus psychoeducation training for staff caring for clients with a personality disorder: a randomized controlled trial.

    PubMed

    Clarke, Sue; Taylor, Georgina; Lancaster, Joanna; Remington, Bob

    2015-04-01

    People diagnosed with a personality disorder (PD) are often a stigmatized patient group. This can affect the care they receive, their progression, and the well-being of staff caring for them. Interventions targeted at health care professionals that aim to improve attitudes toward these patients and improve staff well-being do exist; however, evidence for their effectiveness is limited. The present study compared a self-management, Acceptance and Commitment Therapy-based training intervention (ACTr) with a Psychoeducation Training (PETr) intervention in their effectiveness in improving attitudes toward PD patients, staff-patient relations, and staff well-being. Both interventions were successful at improving attitudes and measures of staff-patient relations up to 6 months after training; however, staff well-being did not change for either group. The implications for staff training and future research are discussed.

  11. Benzoate catabolite repression of the phenol degradation in Acinetobacter calcoaceticus PHEA-2.

    PubMed

    Zhan, Yuhua; Yu, Haiying; Yan, Yongliang; Ping, Shuzhen; Lu, Wei; Zhang, Wei; Chen, Ming; Lin, Min

    2009-10-01

    Acinetobacter calcoaceticus PHEA-2 exhibited a delayed utilization of phenol in the presence of benzoate. Benzoate supplementation completely inhibited phenol degradation in a benzoate 1,2-dioxygenase knockout mutant. The mphR encoding the transcriptional activator and mphN encoding the largest subunit of multi-component phenol hydroxylase in the benA mutant were significantly downregulated (about 7- and 70-fold) on the basis of mRNA levels when benzoate was added to the medium. The co-transformant assay of E. coli JM109 with mphK::lacZ fusion and the plasmid pETR carrying mphR gene showed that MphR did not activate the mph promoter in the presence of benzoate. These results suggest that catabolite repression of phenol degradation by benzoate in A. calcoaceticus PHEA-2 is mediated by the inhibition of the activator protein MphR.

  12. Elastomer rubbers as deflection elements in pressure sensors: investigation of properties using a custom designed programmable elastomer test rig

    NASA Astrophysics Data System (ADS)

    O'Sullivan, S.; Nagle, R.; McEwen, J. A.; Casey, V.

    2003-08-01

    Elastomers are of interest for use as deformation elements in pressure and force sensors. In this paper, a custom designed programmable elastomer test rig (PETR) developed in order to allow the routine mechanical evaluation (compression mode) of small elastomer structures (0.3-30 mm thick) is described and characterized. The mechanical properties of two polyurethane and two silicone rubbers were investigated using the PETR. Silastic silicone (Dow Corning 9161) was found to display relatively low hysteresis and good elasticity. More in-depth investigation of this material revealed that the elastic modulus and the hysteresis were independent of the amount of catalyst used in its preparation over the range 2-6% (w/w). The Zener model was found to provide a good representation of the actual stress-strain behaviour of test specimens subjected to load-unload tests at strain rates in the range 1.25-60% min-1 (load rates 4-200 N min-1) and dynamic tests at frequencies in the range 0.001-0.1 Hz. The combined hysteresis and creep for a 1 h test period was not greater than 4%, with the creep contribution being up to 2.3% and occurring in a manner predicted by the Zener model. Specimen form-factor strongly influenced both the elastic modulus and the hysteresis. Increasing the form-factor from 0.5 to 2.6 increased the elastic modulus from about 3.0 to 7.6 MPa while also increasing the hysteresis from 2.4% to 25.2%.

  13. Influence of Terrestrial Weathering on the Magnetic Record of a LL Chondrite

    NASA Astrophysics Data System (ADS)

    Kohout, T.; Kletetschka, G.; Wasilewski, P.

    2001-12-01

    The origin of our solar system may have been accompanied by transient energetic events capable of magnetizing the materials from which the solid bodies in the solar system formed. The magnetic field associated with some of some of these events should have been recorded by the magnetic mineralogy contained within meteorites. To extract this information from meteorites many noise components must be carefully eliminated. The fusion crust has long been established as restricted to a thin layer on the surface of meteorite. Magnetic screening of the fusion crust that relates to Murchison meteorite indicates that during the entry and landing at least 6 mm thick layer is affected by terrestrial TRM acquisition. Many of the meteorite finds have long term residence in the terrestrial oxidized environment. This weathering is the subject of this study. The meteorite in question landed in the Libya stony desert and has obvious surface weathering that can be referred to as desert varnish. The consequent iron oxide mineralization introduced very stable origin of very stable chemical remanent magnetization. The magnetic remanence in fragments without the desert varnish is between 20 - 50 % of the oxidized ones. The orientation of this CRM appears to be random indicating that the sample may have rotated during the long period of aeolian transport and varnish formation. Magnetization of the white matrix samples (20 - 50 % of weathered ones) is thermally more stable and also randomly oriented. The range of NRM/SIRM values for both mineralogies varies between 10-2 and 10-3. Acknowledgements: This work would not be possible without help of following people: Jakub Haloda, Petr Jakes, Marcela Bukovanska, Petr Pruner, Vladimir Kohout, Libuse Kohoutova, Vladimir Kohout, Olga Kohoutova.

  14. What was driving land-scape drying in the Czech Republic between 1961 and 2012?

    NASA Astrophysics Data System (ADS)

    Hlavinka, Petr; Trnka, Miroslav; Brázdil, Rudolf; Balek, Jan; Semerádová, Daniela; Možný, Martin; Štěpánek, Petr; Dobrovolný, Petr; Zahradníček, Pavel; Dubrovský, Martin; Eitzinger, Josef; Fuchs, Brian; Svoboda, Mark; Hayes, Michael; Žalud, Zdeněk

    2015-04-01

    precipitation thus leading to higher rate of soil moisture withdrawal by plants leaving less water for latter part of growing season. The reported trend patterns are of particular importance with regard to the expected climate change given the robustness and consistency of the trends shown, and the fact that they can be align with existing climate model projections. Finally comparing results of our analysis with available literature we also point out how significantly different might be outcomes of large-scale studies from regionalized assessment. The results have been submitted to International Journal of Climatology. The research was funded by projects "Establishment of International Scientific Team Focused on Drought Research" (no. OP VK CZ.1.07/2.3.00/20.0248) and KONTAKT LH110010 helped plan and execute this study. Petr Hlavinka and Michael Hayes were supported by project "Partnership in Climate Research and Adaptation Strategies" (no. CZ.1.07/2.4.00/31.0056), Rudolf Brázdil and Petr Dobrovolný by projects of the Grant Agency of the Czech Republic (P209/11/0956 and 13-04291S/P209, respectively), and Petr Štěpánek, Martin Možný and Zdeněk Žalud by project of the National Agency for Agricultural Research no. QI91C054, QJ1310123.

  15. Formation of polygonal fault systems as a result of hydrodynamical instabilities in clay-rich deposits.

    NASA Astrophysics Data System (ADS)

    Lopez, Teodolina; Antoine, Raphael; Rabinowicz, Michel; Baratoux, David; Darrozes, José; Kurita, Kei; D'Uston, Lionel

    2015-04-01

    Fine grained deposits as chalks and clays are characterised by the development of polygonal fault systems [1]. For the clay-rich deposits, two different environments are associated with their formation. First, on continents, dewatering leads to the development of polygonal desiccation cracks which have a centimetric to metric size [2]. Polygonal faults are also observed in sub-marine sedimentary deposits and here, can reach hectometric to kilometric size [3]. Since the giant polygons develop on basins with no clear evidences of tectonic stresses, the fracturing is attributed to stresses due to horizontal density variations generated during the basin subsidence. Several models have been proposed to explain the formation of the giant polygons and the two main hypotheses are the syneresis (spontaneous horizontal contraction) proposed by [4] and the low coefficient of friction of clay proposed by [5]. However, new understandings in the clay rheology and in the hydrodynamical instabilities, controlling the development of compaction in unconsolidated and consolidated clay deposits, permit us to propose an alternative hypothesis. We consider that the development of giant polygons results from the superposition of hydrodynamical instabilities leading to the formation of (i) mm-size agglomerates of clay particles while the deposit is unconsolidated [6], followed after by the consolidation of this layer, then (ii) hectometric to kilometric compaction spheres develop [7] and (iii) finally ends with the occurrence of hydrothermal and plastic convections. We show that the crucial conditions for the development of hectometric to kilometric size polygonal fault systems are: 1) the high permeability of the clay-rich deposit composed of mm-size agglomerates and 2) the dramatic increase of the strength of the clay as the deposit consolidates. [1] Dewhurst et al., (1999), Mar. Petr. Geol., 16 (8), 793-810. [2] Weinberger (1999), J. Struct. Geol., 21, 379-386. [3] Andresen and Huuse

  16. Study of the radio-opacity of base and liner dental materials using a digital radiography system

    PubMed Central

    Lachowski, KM; Botta, SB; Lascala, CA; Matos, AB; Sobral, MAP

    2013-01-01

    Objectives: This study investigated the radio-opacity of commercially available glass ionomer cements (GICs), flowable resin composites (FRCs) and calcium hydroxide cements (CHCs) and compared this with the radio-opacity of enamel, dentine and aluminium stepwedge. 16 GICs, 8 FRCs and 4 CHCs were analysed. Methods: Three sets of three samples were prepared: 1 mm, 2 mm and 3 mm thickness for GIC and FRC and 1 mm thickness for CHC. Specimens of enamel and dentine with the same thicknesses were obtained. As a control, an aluminium stepwedge was used. Radiographs were taken with a digital Kodak RVG 5000 (0.32 s, 30 cm). The images were analysed using the Image Tool® program (v. 2.00; The University of Texas Health Science Center, San Antonio, TV) to obtain the mean grey values. Results: Analysis of variance was used to investigate the significance of differences among the groups. For pairwise comparisons, the Tukey test was applied (p < 0.05). The GICs Ionomaster (Wilcos, Petrópolis, Brazil), Maxxion (FGM, Joinville, Brazil), Bioglass R (Biodinâmica, Ibiporã, Brazil), Bioglass F (Biodinâmica), Vidrion R (SS White, Rio de Janerio, Brazil) and Vidrion F (SS White), presented radio-opacity lower than that of dentine. All FRCs and CHCs studied showed radio-opacity higher than that of dentine. Vitro Fil (DFL, Rio de Janeiro, Brazil), Magic Glass (Vigodent, Rio de Janeiro, Brazil), Vitrebond (3M, Sumaré SP, Brazil), Riva Self Cure (SDI, Victoria, Australia), Riva Light Cure (SDI), Fill Magic (Vigodent), Opallis (FGM, Joinville, Brazil), Surefil SDR (Dentsply, Milford, DE), Tetric N (Ivoclar Vivadent, Schaan, Lichtenstein), Tetric (Ivoclar Vivadent), Hydro C (Dentsply, Petrópolis, Brazil), Hydcal (Technew, Madalena, Portugal) and Liner (Vigodent) showed radio-opacity similar to or greater than that of enamel for all thicknesses. Conclusions: The increased thickness of the materials studied increases their radio-opacity. Some commercially available GICs

  17. Saprotrophic capabilities as functional traits to study functional diversity and resilience of ectomycorrhizal community.

    PubMed

    Cullings, Ken; Courty, Pierre-Emmanuel

    2009-10-01

    In an accompanying editorial Dr Petr Baldrian made a case casting doubt on our recent work addressing the saprophytic potential of ectomycorrhizal (EM) fungi. Dr Baldrian's statements illustrate a very valid truth: the book is still very much open on this subject. The point he raised that the only logical reason for these fungi to be responding to high carbon demand or decreased host photosynthetic capacity by up-regulating enzymes is for the purpose of carbon acquisition is valid as well. Despite this, he makes the case that there is no compelling evidence that EM fungi exhibit saprophytic activity. The concept central to Dr Baldrian's conclusion is that even though some EM fungi possess the genes necessary for saprophytic behaviour and may even express these genes, EM fungi do not inhabit a position in the soil column that provides access to usable substrate. In this paper we present both previously published and newly obtained data that demonstrate that this assumption is erroneous, and we present arguments that place the saprophytic potential of EM fungi within a broad ecological context.

  18. Trend, seasonal and multivariate analysis study of total gaseous mercury data from the Canadian atmospheric mercury measurement network (CAMNet)

    NASA Astrophysics Data System (ADS)

    Temme, Christian; Blanchard, P.; Steffen, A.; Banic, C.; Beauchamp, S.; Poissant, L.; Tordon, R.; Wiens, B.

    Long-term monitoring data of total gaseous mercury (TGM) concentrations from the Canadian Atmospheric Mercury Measurement Network (CAMNet) were analysed for temporal trends, seasonality and comparability within the network and compared to other network and model results. Data collected from 11 Canadian measurement sites between 1995 and 2005 were analysed. Sites within CAMNet were characterized by principle component analysis (PCA) into four main categories. For the first time since automated TGM measurements have been made within CAMNet, this paper reveals statistically significant decreasing TGM concentrations from rural locations in Canada during this time period. The largest declines were observed close to the urban areas of Toronto and Montreal, where levels fell by 17% at Point Petre, and 13% at St. Anicet, respectively. Many of the TGM changes are comparable with the overall trends observed in total mercury concentrations in precipitation, for similar time periods, at co-located or nearby National Atmospheric Deposition programme's Mercury Deposition Network (NADP-MDN) sites. The results show that these changes are mostly driven by local or regional changes in mercury emissions. Other sites within CAMNet reflect reported changes in hemispherical global background concentrations of airborne mercury, where slight decreases or no statistically significant trend in TGM concentrations exist over the same time period.

  19. Controlled Ion Acceleration in Two Crossed Laser Beams Propagating in Plasmas

    NASA Astrophysics Data System (ADS)

    Tataronis, J. A.; Petržílka, V.; Krlín, L.

    2003-10-01

    Electron acceleration occurs in a single plane laser beam that is in the presence of a secondary perpendicularly propagating plane laser beam with a randomized phase. As the accelerated electrons are pushed away, they leave the heavier ions behind, producing thereby a charge separation electrostatic field and consequent ion flows. The power flux carried by the accelerated ions can be controlled by varying the intensity of the secondary beam. Results of a numerical study of this control process are presented here. The laser beam parameters chosen for the computations of the primary electron acceleration match the parameters available at the Prague Asterix Laser System (PALS)^1. For the modeling, we use an advanced version of our 3-d two-fluid numerical code^2, originally developed for the analysis of fast electron generation and subsequent ion acceleration in front of lower hybrid wave launchers in large tokamaks. [2pt] ^1K. Jungwirth et al., Phys. Plasmas 8, 2495 (2001). [2pt] ^2V. Petržílka et al., Proc. 29th EPS Conference, Montreux, June 2002, paper 2.105.

  20. Survey of microfungi in the Landschaftspark Duisburg-Nord (Germany).

    PubMed

    Jensen, M; Nerat, N; Ale-Agha, N

    2011-01-01

    During an excursion in the Landschaftspark Duisburg-Nord in 2009 and 2010 we were able to collect and identify more than 100 specimens of microfungi on different parts of cultivated and wild plant species. We found parasitic and saprophytic microfungi on trees, bushes and herbaceous plants. Some of them have been observed only rarely until now. Most of the collected microfungi species belong to the classes of Ascomycetes, Basidiomycetes and Deuteromycetes - for example Leptosphaeria modesta (Desm.) Rabenh. on Knautia cf. arvensis (L.) Coult., Ramularia urticae Ces. on Urtica dioica L., Stigmina glomerulosa (Sacc.) S. Hughes on Juniperus communis L., Pseudomassaria corni (Sowerby) Arx on Cornus alba L., Mollisia discolor (Mont.) W. Phillips on Cornus alba L., Botryosphaeria quercuum (Schwein.) Sacc. on Quercus robur L., Peronospora cytisi Rostr. on Laburnum anagyroides Med., Microsphaera guarinonii Briosi and Cavara on Laburnum anagyroides Med., Brachysporium dingleyae S. Hughes on Fraxinus angustifolia Vahl and Rhododendron spec., Mamiania fimbriata (Pers.) Ces. and De Not. on Carpinus betulus L., Atopospora betulina (Fr.) Petr. on Betula pendula Roth, Septoria robiniae (Lib.) Desm. (=Phloeospora robiniae (Lib.) Höhn.) on Robinia pseudoacacia L., Chalara hughesii Nag Raj and W.B. Kendr. on Quercus robur L.. All specimens are located in the Herbarium ESS, Mycotheca Parva collection G.B. Feige and N. Ale-Agha.

  1. Thermal form factor approach to the ground-state correlation functions of the XXZ chain in the antiferromagnetic massive regime

    NASA Astrophysics Data System (ADS)

    Dugave, Maxime; Göhmann, Frank; Kozlowski, Karol K.; Suzuki, Junji

    2016-09-01

    We use the form factors of the quantum transfer matrix in the zero-temperature limit in order to study the two-point ground-state correlation functions of the XXZ chain in the antiferromagnetic massive regime. We obtain novel form factor series representations of the correlation functions which differ from those derived either from the q-vertex-operator approach or from the algebraic Bethe Ansatz approach to the usual transfer matrix. We advocate that our novel representations are numerically more efficient and allow for a straightforward calculation of the large-distance asymptotic behaviour of the two-point functions. Keeping control over the temperature corrections to the two-point functions we see that these are of order {T}∞ in the whole antiferromagnetic massive regime. The isotropic limit of our result yields a novel form factor series representation for the two-point correlation functions of the XXX chain at zero magnetic field. Dedicated to the memory of Petr Petrovich Kulish.

  2. Magnetomineralogy as a tool for determination of the meteorite weathering

    NASA Astrophysics Data System (ADS)

    Kohout, T.; Kletetschka, G.; Kobr, M.; Pruner, P.; Wasilewski, P. J.

    2002-12-01

    In early solar system history are several electromagnetic processes expected capable of magnetizing the primitive solid particles condensating from the Solar Nebula. The signature of this magnetic events can be observed in meteorites found on the Earth. It can take a long time from meteorite fall till laboratory study. Some samples are deposited in the desert or Antarctic ice for thousands of years. In this work we used the sample of the LL chondrite found in Libya desert for weathering simulations, magnetic mineralogy and magnetic properties study. The weathering in this sample is related to the desert varnish formation. From high and low temperature magnetic susceptibility measurements we can see, that most important magnetic carriers are iron, magnetite and hematite. The influence on magnetic mineralogy can be seen from weathering simulations done by leaching the samples in different solutions. This change affects the suitability of different samples for primary magnetic record study. Acknowledgements: This work is supported by Charles University Grant Agency, Czech Republic and would not be possible without the help of following people: Jakub Haloda, Petr Jakes, Marcela Bukovanska, Jaroslav Kadlec, Libuse Kohoutova, Vladimir Kohout.

  3. COMMITTEES: SQM 2007 - International Conference On Strangeness In Quark Matter SQM 2007 - International Conference On Strangeness In Quark Matter

    NASA Astrophysics Data System (ADS)

    2008-04-01

    Local Organising Committee Ivan Králik (IEP SAS, Košice) Vojtěch Petráček (Czechoslovakia Technical University, Prague) Ján Pišút (Comenius University, Bratislava) Emanuele Quercigh (CERN) Karel Šafařík (CERN), Co-chair Ladislav v Sándor (IEP SAS, Košice), Co-chair Boris Tomášik (Mateja Bela University, Banská Bystrica) Jozef Urbán (UPJŠ Košice) International Advisory Committee Jörg Aichelin, Nantes Federico Antinori, Padova Tamás Biró, Budapest Peter Braun-Munzinger, GSI Jean Cleymans, Cape Town László Csernai, Bergen Timothy Hallman, BNL Huan Zhong Huang, UCLA Sonja Kabana, Nantes Roy A Lacey, Stony Brook Carlos Lourenço, CERN Yu-Gang Ma, Shanghai Jes Masden, Aarhus Yasuo Miake, Tsukuba Berndt Müller, Duke Grazyna Odyniec, LBNL Helmut Oeschler, Darmstadt Jan Rafelski, Arizona Hans Georg Ritter, LBNL Jack Sandweiss, Yale George S F Stephans, MIT Horst Stöcker, Frankfurt Thomas Ullrich, BNL Orlando Villalobos-Baillie, Birmingham William A Zajc, Columbia

  4. Development and testing of meteorology and air dispersion models for Mexico City

    NASA Astrophysics Data System (ADS)

    Williams, M. D.; Brown, M. J.; Cruz, X.; Sosa, G.; Streit, G.

    Los Alamos National Laboratory and Instituto Mexicano del Petróleo are completing a joint study of options for improving air quality in Mexico City. We have modified a three-dimensional, prognostic, higher-order turbulence model for atmospheric circulation (HOTMAC) and a Monte Carlo dispersion and transport model (RAPTAD) to treat domains that include an urbanized area. We used the meteorological model to drive models which describe the photochemistry and air transport and dispersion. The photochemistry modeling is described in a separate paper. We tested the model against routine measurements and those of a major field program. During the field program, measurements included: (1) lidar measurements of aerosol transport and dispersion, (2) aircraft measurements of winds, turbulence, and chemical species aloft, (3) aircraft measurements of skin temperatures, and (4) Tethersonde measurements of winds and ozone. We modified the meteorological model to include provisions for time-varying synoptic-scale winds, adjustments for local wind effects, and detailed surface-coverage descriptions. We developed a new method to define mixing-layer heights based on model outputs. The meteorology and dispersion models were able to provide reasonable representations of the measurements and to define the sources of some of the major uncertainties in the model-measurement comparisons.

  5. Cleaner production and methodological proposal of eco-efficiency measurement in a Mexican petrochemical complex.

    PubMed

    Morales, M A; Herrero, V M; Martínez, S A; Rodríguez, M G; Valdivieso, E; Garcia, G; de los Angeles Elías, Maria

    2006-01-01

    Abstract In the frame of the Petróleos Mexicanos Institutional Program for Sustainable Development, processes were evaluated in the manufacture operation of the petrochemical industry, with the purpose of reducing their ecological fingerprint. Thirteen cleaner production opportunities were registered in six process plants: ethylene oxide and glycols, acetaldehyde, ethylene, high density polyethylene, polypropylene switch and acrylonitrile, and 45 recommendations in the waste water treatment plant. Morelos is the second most important petrochemical complex in the Mexican and Latin American petrochemical industry. A tool was developed to obtain eco-efficiency indicators in operation processes, and as a result, potential savings were obtained based on best performance, as well as the integrated distribution of Sankey diagrams. Likewise, a mechanism of calculation to obtain economic savings based on the reduction of residues during the whole productive process is proposed. These improvement opportunities and recommendations will result in economic and environmental benefits minimising the use of water, efficient use of energy, raw materials and reducing residues from source, generating less environmental impacts during the process.

  6. Structural and Tectonic Map Along the Pacific-North America Plate Boundary in Northern Gulf of California, Sonora Desert and Valle de Mexicali, Mexico, from Seismic Reflection Evidence

    NASA Astrophysics Data System (ADS)

    Gonzalez-Escobar, M.; Suarez-Vidal, F.; Mendoza-Borunda, R.; Martin Barajas, A.; Pacheco-Romero, M.; Arregui-Estrada, S.; Gallardo-Mata, C.; Sanchez-Garcia, C.; Chanes-Martinez, J.

    2012-12-01

    Between 1978 and 1983, Petróleos Mexicanos (PEMEX) carried on an intense exploration program in the northern Gulf of California, the Sonora Desert and the southern part of the Mexicali Valley. This program was supported by a seismic reflection field operation. The collected seismic data was 2D, with travel time of 6 s recording, in 48 channels, and the source energy was: dynamite, vibroseis and air guns. Since 2007 to present time, the existing seismic data has been re-processing and ire-interpreting as part of a collaboration project between the PEMEX's Subdirección de Exploración (PEMEX) and CICESE. The study area is located along a large portion of the Pacific-North America plate boundary in the northern Gulf of California and the Southern part of the Salton Trough tectonic province (Mexicali Valley). We present the result of the processes reflection seismic lines. Many of the previous reported known faults were identify along with the first time described located within the study region. We identified regions with different degree of tectonic activity. In structural map it can see the location of many of these known active faults and their associated seismic activity, as well as other structures with no associated seismicity. Where some faults are mist placed they were deleted or relocated based on new information. We included historical seismicity for the region. We present six reflection lines that cross the aftershocks zone of the El Mayor-Cucapah earthquake of April 4, 2010 (Mw7.2). The epicenter of this earthquake and most of the aftershocks are located in a region where pervious to this earthquake no major earthquakes are been reported. A major result of this study is to demonstrate that there are many buried faults that increase the seismic hazard.

  7. A comparison of the response of Simocephalus mixtus (Cladocera) and Daphnia magna to contaminated freshwater sediments.

    PubMed

    Martínez-Jerónimo, Fernando; Cruz-Cisneros, Jade Lizette; García-Hernández, Leonardo

    2008-09-01

    The southeast region of Mexico is characterized by intensive oil industry activities carried out by the national public enterprise Petróleos Mexicanos (PEMEX). The freshwater lagoon "El Limón", located in the municipality of Macuspana, state of Tabasco, Mexico, has received over 40 years discharges of untreated waste waters from the Petrochemical Complex "Ciudad PEMEX", located on the border of the lagoon. To assess the toxicity of the sediments and, hence, to obtain information on the biological effects of these contaminating discharges, the cladoceran Simocephalus mixtus was used as a test organism in acute (48h) and chronic (12d) toxicity assays. For comparison purposes, bioassays were also conducted with the reference cladoceran Daphnia magna. The sediments of this lagoon contain important amounts of metals and hydrocarbons that have been accumulated over time; however, the acute tests only registered reduced lethal effects on the test organisms (maxima of 10% and 17% mortality for D. magna and S. mixtus, respectively). This may be due to low bioavailability of the pollutants present in the sediments. On the other hand, partial or total inhibition and delay in the start of reproduction, reduction in clutch sizes, reduced survival, as well as reduction in the size of adults and offspring were recorded in the chronic assays. The most evident chronic effects were found in S. mixtus; in this species, reproduction was inhibited up to 72%, whereas D. magna was only affected by 24%. We determined that S. mixtus is a more sensitive test organism than D. magna to assess whole-sediment toxicity in tropical environments, and that chronic exposure bioassays are required for an integrated sediment evaluation. The sediments from "El Limón" lagoon induced chronic intoxication responses and, therefore, remediation measures are urgently needed to recover environmental conditions suitable for the development of its aquatic biota.

  8. National study of illicit drug use in Slovakia based on wastewater analysis.

    PubMed

    Mackuľak, Tomáš; Skubák, Jaroslav; Grabic, Roman; Ryba, Jozef; Birošová, Lucia; Fedorova, Ganna; Spalková, Viera; Bodík, Igor

    2014-10-01

    The aim of this study was to analyze illicit drugs and their metabolites in wastewater from eight selected wastewater treatment plants (WWTPs) in Slovakia. The effect of two of the biggest music festivals in Slovakia on illicit drugs in wastewater was also investigated. Urinary bio-markers of amphetamine, methamphetamine, cocaine, cannabis and ecstasy use were analyzed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). We then compared our results with data obtained in other parts of Europe and the world. This study demonstrates that Slovakia has one of highest methamphetamine consumption rates in Europe. Within Slovakia, the highest level of methamphetamine consumption was found in Petržalka, where the mean specific load of this drug in sewage was 169 mg/day/1000 inhabitants; the next highest loads were detected in Piešťany (128 mg/day/1000 inhabitants) and Bratislava (124 mg/day/1000 inhabitants). Amphetamine, ecstasy and cannabis consumption in our study were comparable to that found in other European cities, whereas cocaine consumption was lower. We also analyzed the pattern of drug consumption over the course of a week. The load of the cocaine metabolite benzoylecgonine in wastewater increased during the weekend. The use of this drug was most common in the capital of Slovakia. Increased consumption was also found during a folk festival in Piešťany. The ecstasy load in wastewater from larger cities also significantly increased over the weekend. An increase of drug consumption was also detected during a music festival in Trenčín, especially for ecstasy. The specific load of ecstasy during this festival increased from 3mg/day/1000 inhabitants to 29 mg/day/1000 inhabitants. The possible influence of music styles on the consumption of certain drugs was also observed. During a folk festival, methamphetamine and cocaine were more commonly used.

  9. Buoyancy-driven convection and mixing in magma chambers - the case of Phlegraean Fields caldera

    NASA Astrophysics Data System (ADS)

    Montagna, Chiara P.; Longo, Antonella; Bagagli, Matteo; Papale, Paolo

    2016-04-01

    Ascent of primitive magmas from depth into shallow, partially degassed reservoirs is commonly assumed to be a viable eruption trigger. At Phlegraean Fields (Southern Italy), processes of convection and mixing have been identified as taking an active part both in pre- and syn-eruptive stages in many eruptions of different size. We performed numerical simulations of magma chamber replenishment referring to an archetypal case whereby a shallow, small magma chamber containing degassed phonolite is invaded by volatile-rich shoshonitic magma coming from a deeper, larger reservoir. The system evolution is solely driven by buoyancy, as the magma entering the shallower chamber is less dense than the degassed, resident phonolite. The evolution in space and time of physical quantities such as pressure, gas content and density is highly heterogeneous; nonetheless, an overall decreasing exponential trend in time can be observed and characterizes the whole process. The same exponentially decreasing trend can be observed in the amplitude of the ground deformation signals (seismicity over the whole frequency spectrum) calculated from the results of the magmatic dynamics. Exponential decay in the efficiency of the mixing process has been also observed experimentally, albeit on much smaller length and time scales (Morgavi et al., Contrib. Min. Petr. 2013). Depending on the initial and boundary conditions explored, such as chamber geometry or density contrast, the time constant thus the duration of the process can vary. Independently, the evolution of pressure in the magmatic system also depends on the initial and boundary conditions, leading either to eruption-favourable conditions or not. Relating the time scales for convective processes to be effective with their outcomes in terms of stresses at the chamber boundaries can substantially improve our ability to forecast eruptions at volcanoes worldwide.

  10. Particulate polycyclic aromatic hydrocarbon spatial variability and aging in Mexico City

    NASA Astrophysics Data System (ADS)

    Thornhill, D. A.; Herndon, S. C.; Onasch, T. B.; Wood, E. C.; Zavala, M.; Molina, L. T.; Gaffney, J. S.; Marley, N. A.; Marr, L. C.

    2007-11-01

    As part of the Megacities Initiative: Local and Global Research Observations (MILAGRO) study in the Mexico City Metropolitan Area in March 2006, we measured particulate polycyclic aromatic hydrocarbons (PAHs) and other gaseous species and particulate properties at six locations throughout the city. The measurements were intended to support the following objectives: to describe spatial and temporal patterns in PAH concentrations, to gain insight into sources and transformations of PAHs, and to quantify the relationships between PAHs and other pollutants. Total particulate PAHs at the Instituto Mexicano del Petróleo (T0 supersite) located near downtown averaged 50 ng m-3, and aerosol active surface area averaged 80 mm2 m-3. PAHs were also measured on board the Aerodyne Mobile Laboratory, which visited six sites encompassing a mixture of different land uses and a range of ages of air parcels transported from the city core. Weak intersite correlations suggest that local sources are important and variable and that exposure to PAHs cannot be represented by a single regional-scale value. The relationships between PAHs and other pollutants suggest that a variety of sources and ages of particles are present. Among carbon monoxide, nitrogen oxides (NOx), and carbon dioxide, particulate PAHs are most strongly correlated with NOx. Mexico City's PAH-to-black carbon mass ratio of 0.01 is similar to that found on a freeway loop in the Los Angeles area and approximately 8-30 times higher than that found in other cities. Ratios also indicate that primary combustion particles are rapidly coated by secondary aerosol in Mexico City. If so, the lifetime of PAHs may be prolonged if the coating protects them against photodegradation or heterogeneous reactions.

  11. Soot and SO2 contribution to the supersites in the MILAGRO campaign from elevated flares in the Tula Refinery

    NASA Astrophysics Data System (ADS)

    Almanza, V. H.; Molina, L. T.; Sosa, G.

    2012-11-01

    This work presents a simulation of the plume trajectory emitted by flaring activities of the Miguel Hidalgo Refinery in Mexico. The flame of a representative sour gas flare is modeled with a CFD combustion code in order to estimate emission rates of combustion by-products of interest for air quality: acetylene, ethylene, nitrogen oxides, carbon monoxide, soot and sulfur dioxide. The emission rates of NO2 and SO2 were compared with measurements obtained at Tula as part of MILAGRO field campaign. The rates of soot, VOCs and CO emissions were compared with estimates obtained by Instituto Mexicano del Petróleo (IMP). The emission rates of these species were further included in WRF-Chem model to simulate the chemical transport of the plume from 22 to 27 March of 2006. The model presents reliable performance of the resolved meteorology, with respect to the Mean Absolute Error (MAE), Root Mean Square Error (RMSE), mean bias (BIAS), vector RMSE and Index of Agreement (IOA). WRF-Chem outputs of SO2 and soot were compared with surface measurements obtained at the three supersites of MILAGRO campaign. The results suggest a contribution of Tula flaring activities to the total SO2 levels of 18% to 27% at the urban supersite (T0), and of 10% to 18% at the suburban supersite (T1). For soot, the model predicts low contribution at the three supersites, with less than 0.1% at three supersites. According to the model, the greatest contribution of both pollutants to the three supersites occurred on 23 March, which coincides with the third cold surge event reported during the campaign.

  12. {Polycyclic aromatic hydrocarbons (PAHs) and aliphatic hydrocarbons in gas and particle phases in two sites of Mexico: MILAGRO project}

    NASA Astrophysics Data System (ADS)

    Amador-Muñoz, O.; Villalobos-Pietrini, R.; Castro, T.; Gaspariano-Larino, R.

    2009-04-01

    Aliphatic hydrocarbons are markers of anthropogenic and biogenic emission sources1; meanwhile PAHs are generated by incomplete combustion sources2. The last ones are important compounds due to their carcinogenic and mutagenic properties3,4. The aim of this study was to identify and quantify aliphatic hydrocarbons and PAHs in gas and particles phases of the atmospheric aerosol and to determine the day and night time behavior during the MILAGRO (Megacity Initiative: Local Global and Research Observations) campaign. The gas phase was collected on polyurethane foam, while particles less than 2.5 m (PM2.5) were collected on glass fiber filters covered with Teflon (TIGF, pallflex) of 8x10 in. Samplings were carried out with a high volume sampler (Tisch) with a flow of 1.13 m3 min-1 at two sites: Instituto Mexicano del Petróleo (T0) and Tecamac (T1) located at North and Northeast of Mexico City, respectively during day (7:00 am-7:00 pm) and night time (7:00 pm-7:00 am) from 1 to 29 of March, 2006. Ninteen PAHs and 23 aliphatic hydrocarbons from n-C13H28 to n-C35H72 were analyzed by gas chromatography coupled to mass spectrometry in impact mode. The samples were spiked with deuterads PAHs and aliphatics hydrocarbons before ultrasound extraction. Medians comparisons were made with Mann-Whitney U test. PAHs with molecular weight (MW) less than 228 g mol-1 were distributed in the gas phase, in both sites. Higher concentrations of PAHs ≥ 228 g mol-1 in PM2.5, were observed during night period (p

  13. PREFACE: 5th European Conference on Neutron Scattering

    NASA Astrophysics Data System (ADS)

    Mikula, Pavel; Hlinka, Jiří; Prokeš, Karel; Dohnálek, Jan; Šittner, Petr; Javorský, Pavel

    2012-02-01

    This volume contains proceedings of ECNS 2011, held in Prague, Czech Republic, 17-22 July 2011. ECNS 2011 was the fifth Conference in a series of meetings organized in various European cities under patronage of the European Neutron Scattering Association, and was preceded by the European Neutron Scattering Conferences in Interlaken (1996), Budapest (1999), Montpellier (2003) and Lund (2007). The positive atmosphere of the Prague meeting of the neutron community can certainly be attributed to recent progress in the extension of the European neutron experimental base, in particular the completion of the ISIS second target station and considerable progress in the European Spallation Source project in Lund. The success of ECNS 2011 has been manifested by the participation of 698 scientists from 36 countries, who presented 231 talks and 534 posters. This proceedings contains 112 papers from authors who wished to have the written versions of their contributions published. The contributions illustrate the broad scale of scientific problems investigated by neutron scattering methods and give a picture of growing activities in the field. The conference chairmen wish to express their thanks to all colleagues who contributed to the organization and preparation of ECNS 2011, in particular the members of the International Advisory Committee, the International Program Committee and the Local Organizing Committee. We very much appreciate the role of Professor Michael Steiner, the President of ENSA, and all ENSA representatives who contributed valuable conceptual input and advice in the preparatory phase of the conference organization. Special thanks go to the editors and all the referees who helped us to publish the ECNS 2011 Proceedings in such a short time. Vladimír SechovskýPetr Lukáš Conference chairmen The PDF contains photographs from the conference and a full list of participants.

  14. Temporal variations in the mantle potential temperatures along the Northwest Hawaiian Ridge using olivine-liquid equilibria: Implications for Hawaiian plume melt flux variations

    NASA Astrophysics Data System (ADS)

    Tree, J. P.; Garcia, M. O.; Putirka, K. D.

    2013-12-01

    The Northwest Hawaiian Ridge extends 2800 km and comprises 47% of the total length of the Hawaiian-Emperor (H-E) Chain. The Ridge contains at least 52 volcanoes whose shape, volume, and distance from neighboring volcanoes vary markedly. The temporal melt flux variation of the H-E has been estimated with various geophysical methods involving fluid dynamics and lithospheric modeling. These models show a dramatic increase (up to 300%) in melt flux over the last 30 Myr. A potential explanation for the increase in melt flux is a temporal increase in the temperature of melting. Olivine thermometry offers the best method for evaluating mantle source temperature variations along the Ridge. An olivine-liquid equilibration temperature estimate can then be recast into a mantle potential temperature after accounting for the heat of fusion during mantle melting and decompression of the mantle as it follows an adiabat to the surface. New whole-rock XRF and olivine analyzes for 18 tholeiitic, three transitional tholeiites, and two picro-basalts from 11 volcanoes spanning the entire length of the Ridge from Middle Bank to Yuryaku (just south of the Bend) were made. These data were used to obtain a temperature estimate of the mantle during shield formation of each volcano. After screening samples for those in chemical equilibrium using a Rhodes diagram and assuming a Kdol-liq(Fe-Mg)=0.345 ×0.03, data from six volcanoes were input into the thermometers of Beattie (1993; Contrib. Mineral. Petr., 118, 103-111) and Putirka et al., (2007; Chemical Geology, 241, 177-206). The results were averaged to estimate mantle potential temperatures. These calculations yield mantle potential temperature estimates that vary positively with volcano volume (e.g., 1460oC at Yuryaku vs 1608-1630oC at Gardner Pinnacles, the largest volume seamount in the Ridge). These results suggest that temperature variations may be playing a significant role in modulating the melt flux of the Ridge. Seven more

  15. Effects of bleaching with carbamide peroxide gels on microhardness of restoration materials.

    PubMed

    Campos, Inger; Briso, André Luiz Fraga; Pimenta, Luiz André Freire; Ambrosano, Gláucia

    2003-01-01

    The objective of this in vitro study was to quantitatively assess the effects of bleaching with 10 and 15% carbamide peroxide (CP) on restoration materials by performing superficial microhardness analysis. Acrylic cylindrical containers (4 x 2 mm) were filled with the following restoration products: Charisma (Heraues Kulzer, Vila Santa Catarina, São Paulo, Brazil), Durafill VS (Heraeus Kulzer), Vitremer (3M, Sumaré, São Paulo, Brazil), Dyract (Dentsply, Petrópolis, Rio de Janeiro, Brazil), and Permite C (SDI, São Paulo, São Paulo, Brazil). Sixty samples were prepared of each restoration material. Twenty samples received bleaching treatment with 10% CP, 20 samples received bleaching treatment with 15% CP, and 20 samples were kept submerged in artificial saliva, which was replaced daily. The treatment consisted of immersion of the specimens in 1 cm3 of CP at 10 and 15% for 6 hours per day during 3 weeks, whereupon the test specimens were washed, dried, and kept immersed in artificial saliva for 18 hours. Then the test and control specimens were analyzed using a microhardness gauge. The Knoop Hardness Number (KHN) was taken for each test and control specimen at five different locations by applying a 25 g force for 20 seconds. The values obtained were transformed into KHNs and the mean was calculated. The data were submitted to statistical analysis by analysis of variance and Tukey test, p < .05. The means/standard deviations were as follows: Charisma: CP 10% 38.52/4.08, CP 15% 34.31/6.13, saliva 37.36/4.48; Durafill VS: CP 10% 18.65/1.65, CP 15% 19.38/2.23, saliva 18.27/1.43; Dyract AP: CP 10% 30.26/2.81, CP 15% 28.64/5.44, saliva 33.88/3.46; Vitremer: CP 10% 28.15/3.04, CP 15% 17.40/3.11, saliva 40.93/4.18; and Permite C: CP 10% 183.50/27.09, CP 15% 159.45/5.78, saliva 215.80/26.15. A decrease in microhardness was observed for the materials Dyract AP, Vitremer, and Permite C after treatment with CP at 10 and 15%, whereas no effect on either of the two

  16. Laser Raman Spectroscopic Confirmation of Maskelynite in the Bedout Impact Breccia, Offshore, NW Australia.

    NASA Astrophysics Data System (ADS)

    Basu, A. R.; Chakrabarti, R.; Peterson, J.; Poreda, R. J.; Becker, L.

    2004-12-01

    We report the results of a detailed laser Raman spectroscopic study of isotropic plagioclase laths ( ˜An50) from the 9986 ft. core sample of the Bedout High, interpreted recently by us (Becker et al. Science, 304, p1469, 2004) as the possible remnant of an end-Permian impact crater, offshore of NW Australia. These plagioclase laths are associated with spherulitic glass fragments of nearly pure silica in composition, as well as pure albite and other heterogeneous glassy fragments in a highly brecciated volcanic-like host rock. We performed laser Raman analysis on the same grains shown in Fig 6 of our paper referred above and identified as maskelynite. We also performed a comparative analysis of other known shocked plagioclase grains from the Manicouagan Crater, Canada and from the Lonar Crater, India (to be reported in this meeting, Chakrabarti et al.) Raman scattering measurements were performed using the 514.5 nm line of an argon ion laser at an intensity of 40 kW/cm2. An inverted microscope (Nikon TE3000) with 50x objective (NA 0.55) was used for confocal imaging. A holographic notch filter removed residual laser scatter and the Raman scattering was detected by a silicon CCD at -900 C (Princeton Instruments Spec10-400R). Raman spectra were collected from ~250 cm-1 through 2000 cm-1 in all these samples. An anisotropic plagioclase lath from the same 9986 polished thin section shows prominent peaks at 827 cm-1, 1109 cm-1 and 1180 cm-1 with much smaller peaks at 433 cm-1 and 634 cm-1. The Raman spectra of the isotropic grains of Fig 6 from our earlier study are conspicuously featureless and show a progressive increase in the luminescent background with higher wave numbers. Our observations are consistent with the Raman spectra of experimentally shocked plagioclase (Heymann and Herz, 1990, Cont. Min. Petr. 17, 38-44, 1990) as well as those of plagioclases from the tektites of the Lonar Impact Crater. Therefore we strongly believe that we had correctly identified

  17. Laser Raman Spectroscopic Characterization of Shocked Plagioclase from the Lonar Impact Crater, India.

    NASA Astrophysics Data System (ADS)

    Chakrabarti, R.; Basu, A. R.; Peterson, J.; Misra, S.

    2004-12-01

    from one grain to another, perhaps due to difference in composition. This observation is consistent with previously reported analyses of unshocked plagioclase feldspars. The Raman spectra of the maskelynites from the tektite samples show more flattened-out patterns. Earlier studies have reported the "disappearance" of peaks due to an increased luminescent background in experimentally shocked single plagioclase grains (Heymann and Herz, 1990, Cont. Min. Petr. 17, 38-44, 1990). Our study in multiple variably shocked plagioclase grains of the Lonar basalt impact breccia further corroborates these previous observations and reinstates the importance of Raman Spectroscopy in identifying shocked plagioclase grains.

  18. Spatially distributed soil water content in a small forested catchment and its relation to the catchment water budget on various timescales

    NASA Astrophysics Data System (ADS)

    Graf, Alexander; Bogena, Heye R.; Hardelauf, Horst; Pütz, Thomas; Drüe, Clemens; Heinemann, Günther; Vereecken, Harry

    2014-05-01

    In the framework of the TERENO project, terrestrial observatories have been implemented in order to observe hydrological phenomena at several scales, from small highly instrumented headwater catchments to mesoscale watersheds. At the headwater catchment scale, field experiments are conducted in which the effects of land use change are monitored to provide empirical data describing hydrological processes and responses. The TERENO test site Wüstebach is a 38.5 ha small forested headwater catchment located in a low mountain range in Germany. For a period of 3 years prior to a partial deforestation in 2013, the catchment hydrology has been characterized by continuous measurements of runoff (R), actual evapotranspiration based on the eddy-covariance method (ET), and soil water content at 3 depths in 109 locations (θ). With nearby measurements of precipitation (P), as well as potential evapotranspiration (PET) for regression-based gap filling of ET, it was possible to analyse the water budget without relying on process-based models. The long-term water budget P-ET-R was closed with a residual of less than 3% of annual precipitation. On the daily timescale, the increasing residual of the water budget was explained to a moderate extent by soil water content (R² = 0.40). Wavelet coherence analysis revealed timescales of about 4 days and less, which were presumably dominated by unaccounted fast-turnover storage terms such as interception, as a major source of uncertainty. At weekly resolution, soil water storage explained more than half (R² = 0.62) of the water budget residual. By means of a combined empirical orthogonal function and cluster analysis, differences in the spatial pattern of soil water content between wet and dry state (above and below 0.35 cm³/cm³ spatially averaged soil water content) of the catchment could be identified. Various analyses confirmed that ET was predominantly energy-limited, but gradually lost coherence with PET and thus energy supply

  19. Macroperipatus ohausi: redescription and taxonomic notes on its status (Onychophora: Peripatidae).

    PubMed

    Chagas-Júnior, Amazonas; Costa, Cristiano Sampaio

    2014-09-01

    Onychophora have undergone a new wave of taxonomic revisions in the last three years. After a recent revision, only two species of Macroperipatus are registered from Brazil: Macroperipatus ohausi and Macroperipatus geayi. The former was only the second species of Onychophora to be described from Brazil, and is herein redescribed, illustrated, and its taxonomic status revised. Macroperipatus ohausi had only been collected at the type locality, Petrópolis, state of Rio de Janeiro, but has not been found there since its discovery. In 2009 we collected two specimens of this species in an Atlantic rain forest fragment in Nova Iguaçu in RPPN dos Petroleiros (also state of Rio de Janeiro). The color of the new specimens was interpreted and described based on the NBS/ISCC System of Color Designation, and corresponds only weakly to that described in earlier publications on M ohausi. The identification of M. ohausi was based solely on its morphology and compared with its original description. In addition, a female syntype of M. ohausi deposited in the Zoologisches Museum (Hamburg) was examined. We reinvestigated its external morphology and concluded that the dorsal papillae have been misinterpreted in M ohausi in previous studies of its integument. The new specimens examined are conspecific with M ohausi mainly by having conical primary papillae, different sized accessory papillae, and by the number of legs. Our material resembles.the original description of M ohausi, for example, in spinous pad and nephridial tubercles, even though these features are not represented in the original description and redescription ofM. ohausi; these features are further detailed here. We concluded that the dorsal papillae morphology of M ohausi, shares diagnostic characters, for example, with representatives of the genera Peripatus and Epiperipatus. The dorsal papillae are rounded and not square as in the original description and redescription. Another argument that supports our conclusion

  20. Implications of spinel compositions for the petrotectonic history of abyssal peridotite from Southwest Indian Ridge (SWIR)

    NASA Astrophysics Data System (ADS)

    Chen, T.; Jin, Z.; Wang, Y.; Tao, C.

    2012-12-01

    . References [1] Dick, H.J.B., et al., Contrib Mineral Petr., 86:54, 1984. [2] Hellebrand et al., Nature, 410: 677, 2001. [3] Hamdy, M.M. , et al., JGMR, 3(9): 232, 2011.

  1. S-wave Anisotropy and Crack Distribution at the Coso Geothermal Field, California

    NASA Astrophysics Data System (ADS)

    Vlahovic, G.; Elkibbi, M.; Rial, J. A.

    2001-05-01

    is closer than any other in the CDDSN to the production well. Lou, M. and J. A. Rial, Geophysics, 62, 487-494, (1997). Malin, P. E., Transactions of the Geothermal Research Council, 18, 17-22, (1994). Moore, J. N. and M. C. Erskine, Am. Assn. Petr. Geol. EMD 1, 41-61, (1990).

  2. Continuous eclogite melting and variable refertilisation in upwelling heterogeneous mantle

    NASA Astrophysics Data System (ADS)

    Rosenthal, A.; Yaxley, G. M.; Green, D. H.; Frost, D. J.; Kovacs, I.; Spandler, C.; Hermann, J.

    2015-12-01

    along adiabatic paths [1, this study]. Densities and seismic velocities of eclogitic residues also differ during upwelling. Subsequent melting of these sources may lead to compositional diversity in volcanic rocks. [1] Rosenthal et al. Sci Rep 4, 6099 (2014) [2] Spandler et al. J Petrol 49, 771-795 (2008) [3] Yaxley & Green Schweiz Mineral Petr Mitt 78, 243-255 (1998)

  3. The IVA Parent Body: Evidence from Silicate-Bearing Group IVA Iron Meteorites

    NASA Astrophysics Data System (ADS)

    Ulff-Moller, F.; Kallemeyn, G. W.; Rasmussen, K. L.

    1992-07-01

    Plockinger E. (1965) Tschermacks Min. Petr. Mitt. 10, 413-429. Schaudy R., Wasson J.T. and Buchwald V.F. (1972) Icarus 17, 174-192. Reid A.M., Williams R.J. and Takeda H. (1974) Earth Planet. Sci. Lett. 22, 67-74.

  4. Macroperipatus ohausi: redescription and taxonomic notes on its status (Onychophora: Peripatidae).

    PubMed

    Chagas-Júnior, Amazonas; Costa, Cristiano Sampaio

    2014-09-01

    Onychophora have undergone a new wave of taxonomic revisions in the last three years. After a recent revision, only two species of Macroperipatus are registered from Brazil: Macroperipatus ohausi and Macroperipatus geayi. The former was only the second species of Onychophora to be described from Brazil, and is herein redescribed, illustrated, and its taxonomic status revised. Macroperipatus ohausi had only been collected at the type locality, Petrópolis, state of Rio de Janeiro, but has not been found there since its discovery. In 2009 we collected two specimens of this species in an Atlantic rain forest fragment in Nova Iguaçu in RPPN dos Petroleiros (also state of Rio de Janeiro). The color of the new specimens was interpreted and described based on the NBS/ISCC System of Color Designation, and corresponds only weakly to that described in earlier publications on M ohausi. The identification of M. ohausi was based solely on its morphology and compared with its original description. In addition, a female syntype of M. ohausi deposited in the Zoologisches Museum (Hamburg) was examined. We reinvestigated its external morphology and concluded that the dorsal papillae have been misinterpreted in M ohausi in previous studies of its integument. The new specimens examined are conspecific with M ohausi mainly by having conical primary papillae, different sized accessory papillae, and by the number of legs. Our material resembles.the original description of M ohausi, for example, in spinous pad and nephridial tubercles, even though these features are not represented in the original description and redescription ofM. ohausi; these features are further detailed here. We concluded that the dorsal papillae morphology of M ohausi, shares diagnostic characters, for example, with representatives of the genera Peripatus and Epiperipatus. The dorsal papillae are rounded and not square as in the original description and redescription. Another argument that supports our conclusion

  5. VGG2002, a new high-resolution geoid for Venezuela and Eastern Caribbean

    NASA Astrophysics Data System (ADS)

    Acuña, G.; Bosch, W.

    2003-04-01

    This paper describes a new high-resolution geoid for Venezuela and the East Caribbean Sea. The Venezuelan Gravimetric Geoid 2002 (VGG2002) covers the area between 0oN-20oN and 285oE-305oE with a resolution of 1'x1'. An additional 2o-zone was included to avoid boundary effects. About 1.5 million free-air gravity anomalies were used. They originate from PDVSA (Petróleos de Venezuela S.A.), BGI (Bureau Gravimetrique International) and the GEODAS data base of NGDC (National Geophysical Data Center). In marine areas, 1'x1' gravity anomalies derived from altimetry (S&Sv9.1) were also included. In order to determined the long wavelength geoid signal the EGM96 global geopotential model was used as reference. Short wavelength contributions were derived from a digital terrain model with 30'' (GTOPO30 model) and 2' (S&Sv8.2 model) resolution respectively. Using the GRAVSOFT software, the geoid undulations were computed with the remove-restore technique. The computation involves a spherical approximation to evaluate the Stokes integral by two dimensional spherical Fast Fourier Transform with 100% zero-padding. The terrain corrections were computed by Residual Terrain Model method using prism numeric integration and taking into account the topographic anomalies relative to a mean height surface of 15'x15' resolution. This surface was obtained by a moving average of the digital terrain model. In marine areas the height anomalies were completed by mean sea level deviations of POCM, an oceanographic model of the ocean dynamic topography. Subsequently, the quasi-geoid was converted to geoid heights. The accuracy was evaluated by about 300 GPS/leveling stations and absolute differences to TOPEX/Poseidon (nine years) mean sea surface profiles. These show that the absolute agreement with respect to the national vertical datum is generally better than 30 cm RMS for most parts of Venezuela, 15 cm RMS in coastal areas and 5 cm RMS at sea.

  6. Paleoseismology in Venezuela: Objectives, methods, applications, limitations and perspectives

    NASA Astrophysics Data System (ADS)

    Audemard M., Franck A.

    2005-10-01

    The privileged location of Venezuela along an active interplate deformation belt, despite of being a "so-called" developing country, has led to a long paleoseismic tradition as attested by 45 trench assessments since 1968. Since then, a first 2-trench study was carried out by the American Woodward-Clyde company across the Oca fault at Sinamaica. Since 1980, all further paleoseismic studies have been performed by FUNVISIS and the Uribante-Caparo hydroelectric project (southern Mérida Andes) became their first assessment where 22 huge trenches were bulldozer-dug. Except for these Compañía Anónima de Administración y Fomento Eléctrico (CADAFE) financed trenches and two others, all other assessments were for Petróleos de Venezuela S. A. -PDVSA-. In this paper, geographic and geologic factors, as well as logistic limitations, conditioning success in paleoseismic studies by trenching, shall be discussed based on the Venezuelan experience developed over the years. The scientific contribution of this approach refer to: confirmation of Holocene fault activity, slip-per-event and average slip rate of a given fault (or segment), seismic potential (repeat of maximum credible earthquakes) of known faults, fault segmentation, fault interaction as consequence of stress loading by stick-slip on contiguous faults, time-space distribution of seismic activity along a given tectonic feature, seismotectonic association of historical earthquakes and landscape evolution on the short term and its implications on the long-term evolution (poorly discussed since this is really part of the field of Neotectonics). In recent years (since 1999), a new approach has been introduced in Venezuela consisting in complementing the seismic history derived from trenching studies with the evaluation of seismically induced perturbations in the continuous Quaternary sedimentary record of (either active or fossil) lakes. The future of this discipline in Venezuela heads to more trenching and lake

  7. Depositional history of the post-glacial transgression on the outer continental shelf of the Gulf of Lions (western Mediterranean)

    NASA Astrophysics Data System (ADS)

    Bassetti, M. A.; Jouet, G.; Berne, S.; Taviani, M.; Leroux, E.; Perez-Belmonte, L.

    2004-12-01

    TST-HST margin deposits but they clearly document the effect of the sea level change on sedimentation pattern in wave-dominated shelf environment. Aloisi, J.C, Monaco, A., Thommeret, J., Thommeret Y. Géogr. Phys.Quatern., 32, 145-162, (1978). Rabineau, M., Berne, S., Ledrezen, E., Lericolais, G., Marsset, T., Rotunno, M. Mar.Petr.Geol., 15, 439-452, (1998).

  8. Application of artificial neural networks for conformity analysis of fuel performed with an optical fiber sensor

    NASA Astrophysics Data System (ADS)

    Possetti, Gustavo Rafael Collere; Coradin, Francelli Klemba; Côcco, Lílian Cristina; Yamamoto, Carlos Itsuo; de Arruda, Lucia Valéria Ramos; Falate, Rosane; Muller, Marcia; Fabris, José Luís

    2008-04-01

    The liquid fuel quality control is an important issue that brings benefits for the State, for the consumers and for the environment. The conformity analysis, in special for gasoline, demands a rigorous sampling technique among gas stations and other economic agencies, followed by a series of standard physicochemical tests. Such procedures are commonly expensive and time demanding and, moreover, a specialist is often required to carry out the tasks. Such drawbacks make the development of alternative analysis tools an important research field. The fuel refractive index is an additional parameter to help the fuel conformity analysis, besides the prospective optical fiber sensors, which operate like transducers with singular properties. When this parameter is correlated with the sample density, it becomes possible to determine conformity zones that cannot be analytically defined. This work presents an application of artificial neural networks based on Radial Basis Function to determine these zones. A set of 45 gasoline samples, collected in several gas stations and previously analyzed according to the rules of Agência Nacional do Petróleo, Gás Natural e Biocombustíveis, a Brazilian regulatory agency, constituted the database to build two neural networks. The input variables of first network are the samples refractive indices, measured with an Abbe refractometer, and the density of the samples measured with a digital densimeter. For the second network the input variables included, besides the samples densities, the wavelength response of a long-period grating to the samples refractive indices. The used grating was written in an optical fiber using the point-to-point technique by submitting the fiber to consecutive electrical arcs from a splice machine. The output variables of both Radial Basis Function Networks are represented by the conformity status of each sample, according to report of tests carried out following the American Society for Testing and Materials

  9. Measurements of HNO3 and N2O5 using ion drift-chemical ionization mass spectrometry during the MILAGRO/MCMA-2006 campaign

    NASA Astrophysics Data System (ADS)

    Zheng, J.; Zhang, R.; Fortner, E. C.; Volkamer, R. M.; Molina, L.; Aiken, A. C.; Jimenez, J. L.; Gaeggeler, K.; Dommen, J.; Dusanter, S.; Stevens, P. S.; Tie, X.

    2008-11-01

    An ion drift-chemical ionization mass spectrometer (ID-CIMS) was deployed in Mexico City between 7 and 31 March to measure gas-phase nitric acid (HNO3) and dinitrogen pentoxide (N2O5 during the Mexico City Metropolitan Area (MCMA)-2006 field campaign. The observation site was located at the Instituto Mexicano del Petróleo in the northern part of Mexico City urban area with major emissions of pollutants from residential, vehicular and industrial sources. Diurnally, HNO3 was less than 200 parts per trillion (ppt) during the night and early morning. The concentration of HNO3 increased steadily from around 09:00 a.m. central standard time (CST), reached a peak value of 0.5 to 3 parts per billion (ppb) in the early afternoon, and then declined sharply to less than half of the peak value near 05:00 p.m. CST. An inter-comparison between the ID-CIMS and an ion chromatograph/mass spectrometer (ICMS) showed a good agreement between the two HNO3 measurements (R2=0.75). The HNO3 mixing ratio was found to anti-correlate with submicron-sized aerosol nitrate, suggesting that the gas-particle partitioning process was a major factor in determining the gaseous HNO3 concentration. Losses by irreversible reactions with mineral dust and via dry deposition also could be important at this site. Most of the times during the MCMA 2006 field campaign, N2O5 was found to be below the detection limit (about 30 ppt for a 10 s integration time) of the ID-CIMS, because of high NO mixing ratio at the surface (>100 ppb) during the night. An exception occurred on 26 March 2006, when about 40 ppt N2O5 was observed during the late afternoon and early evening hours under cloudy conditions before the build-up of NO at the surface site. The results revealed that during the MCMA-2006 field campaign HNO3 was primarily produced from the reaction of OH with NO2 and regulated by gas/particle transfer and dry deposition. The production of HNO3 from N2O5 hydrolysis during the nighttime was small because of

  10. The two Faces of Equipartition

    NASA Astrophysics Data System (ADS)

    Sanchez-Sesma, F. J.; Perton, M.; Rodriguez-Castellanos, A.; Campillo, M.; Weaver, R. L.; Rodriguez, M.; Prieto, G.; Luzon, F.; McGarr, A.

    2008-12-01

    relationship of average autocorrelations with the imaginary part of Green function at the source. Preliminary results are displayed in data sets from Chilpancingo, Mexico, and the Tautona Gold Mine, South Africa, that strongly suggest that equipartition, that guarantees the diffuse nature of seismic fields, has more than one face. Acknowledgements. Partial supports from DGAPA-UNAM, Project IN114706, Mexico; from Proyect MCyT CGL2005-05500-C02/BTE, Spain; from project DyETI of INSU-CNRS, France, and from the Instituto Mexicano del Petróleo are greatly appreciated.

  11. Measurements of HNO3 and N2O5 using Ion drift - Chemical Ionization Mass Spectrometry during the MCMA - 2006 Campaign

    NASA Astrophysics Data System (ADS)

    Zheng, J.; Zhang, R.; Fortner, E. C.; Molina, L.; Aiken, A. C.; Jimenez, J. L.; Gäggeler, K.; Dommen, J.; Dusanter, S.; Stevens, P. S.; Tie, X.

    2008-03-01

    An ion drift - chemical ionization mass spectrometry (ID-CIMS) was deployed in Mexico City between 5 and 31 March to measure HNO3 and N2O5 during the 2006 Mexico City Metropolitan Area (MCMA) field campaign. The observation site, T0, was located at the Instituto Mexicano del Petróleo at the center of the Mexico City Basin with major emissions of pollutants from both domestic and industrial sources. Diurnally, HNO3 was less than 200 parts per trillion (ppt) during the night and in the early morning, increased steadily from around 09:00 a.m. central standard time (CST), reached a peak value of 0.5 to 3 parts per billion (ppb) in the early afternoon, and declined sharply to less than half of the peak value near 05:00 p.m. CST. An inter-comparison between the ID-CIMS and an ion chromatograph/mass spectrometer (ICMS) showed a good correlation in the HNO3 measurements (R2=0.75). The HNO3 mixing ratio was found to anti-correlate with aerosol nitrate, suggesting that the gaseous HNO3 concentration was controlled by the gas-particle partitioning process. During most times of the MCMA 2006 field campaign, N2O5 was found to be under the detection limit (about 20 ppt for a 10 s integration time) of the ID-CIMS, because of high NO mixing ratio (>100 ppb) during the night. With one exception on 26 March 2006, about 40 ppt N2O5 was observed during the late afternoon and early evening hours under a cloudy condition, before NO built up at the surface site. The results revealed that during the 2006 MCMA field campaign HNO3 was primarily produced by the reaction of OH with NO2 and regulated by gas/particle partitioning, and HNO3 production from N2O5 hydrolysis during the nighttime was small because of high NO and low O3 concentrations near the surface.

  12. Spatial and temporal variability of particulate polycyclic aromatic hydrocarbons in Mexico City

    NASA Astrophysics Data System (ADS)

    Thornhill, D. A.; de Foy, B.; Herndon, S. C.; Onasch, T. B.; Wood, E. C.; Zavala, M.; Molina, L. T.; Gaffney, J. S.; Marley, N. A.; Marr, L. C.

    2008-06-01

    As part of the Megacities Initiative: Local and Global Research Observations (MILAGRO) study in the Mexico City Metropolitan Area in March 2006, we measured particulate polycyclic aromatic hydrocarbons (PAHs) and other gaseous species and particulate properties, including light absorbing carbon or effective black carbon (BC), at six locations throughout the city. The measurements were intended to support the following objectives: to describe spatial and temporal patterns in PAH concentrations, to gain insight into sources and transformations of PAHs and BC, and to quantify the relationships between PAHs and other pollutants. Total particulate PAHs at the Instituto Mexicano del Petróleo (T0 supersite) located near downtown averaged 50 ng m-3, and aerosol active surface area averaged 80 mm2 m-3. PAHs were also measured on board the Aerodyne Mobile Laboratory, which visited six sites encompassing a mixture of different land uses and a range of ages of air parcels transported from the city core. A combination of analyses of time series, back trajectories, concentration fields, pollutant ratios, and correlation coefficients supports the concept of T0 as an urban source site, T1 as a receptor site with strong local sources, Pedregal and PEMEX as intermediate sites, Pico Tres Padres as a vertical receptor site, and Santa Ana as a downwind receptor site. Weak intersite correlations suggest that local sources are important and variable and that exposure to PAHs and BC cannot be represented by a single regional-scale value. The relationships between PAHs and other pollutants suggest that a variety of sources and ages of particles are present. Among carbon monoxide, nitrogen oxides (NOx), and carbon dioxide, particulate PAHs are most strongly correlated with NOx. Mexico City's PAH/BC mass ratio of 0.01 is similar to that found on a freeway loop in the Los Angeles area and approximately 8 30 times higher than that found in other cities. Evidence also suggests that primary

  13. Measurements of aerosol absorption and scattering in the Mexico City Metropolitan Area during the MILAGRO field campaign: a comparison of results from the T0 and T1 sites

    NASA Astrophysics Data System (ADS)

    Marley, N. A.; Gaffney, J. S.; Castro, T.; Salcido, A.; Frederick, J.

    2008-07-01

    Measurements of aerosol absorption and scattering were obtained in Mexico City during the MILAGRO (Megacity Initiative: Local and Global Research Observations) field campaign in March 2006. A comparison of aerosol absorption and scattering was obtained in Mexico City at site T0 located in the northern part of Mexico City at the Instituto Mexicano del Petróleo Laboratories and at site T1 located at the Universidad Tecnológica de Tecamac, 18 miles northwest of T0. Hourly averages of aerosol absorption were similar at both sites, ranging from 6 93 Mm-1 with an average of 31 Mm-1 at T0; and from 2 104 Mm-1 with an average of 19 Mm-1 at T1. Aerosol scattering at T0 ranged from 16 344 Mm-1 with an average of 105 Mm-1; while the scattering values at T1 were lower than T0 ranging from 2 136 with an average of 53 Mm-1. Aerosol single scattering albedos (SSAs) were determined at both sites using these data. SSAs at T1 ranged from 0.44 0.90 with an average 0.75 as compared to hose at T0, range 0.51 0.93 with an average of 0.77. Broadband UV-B intensity was found to be higher at site T0, with an average of 64 μW/cm2 at solar noon, than at site T1, which had an average of 54 μW/cm2 at solar noon. Comparisons of clear-sky modeled UV-B intensities with the simultaneous UV-B measurements obtained at site T0 and at site T1 for cloudless days indicate a larger diffuse radiation field at site T0 than at site T1. The determination of aerosol scattering Ångstrom coefficient at T0 suggests the larger diffuse radiation is due to the predominance of submicron aerosols at T0 with aerosol scattering of UV-B radiation peaked in the forward direction, leading to the enhancement observed at ground level.

  14. Diffuse Waves and Energy Densities Near Boundaries

    NASA Astrophysics Data System (ADS)

    Sanchez-Sesma, F. J.; Rodriguez-Castellanos, A.; Campillo, M.; Perton, M.; Luzon, F.; Perez-Ruiz, J. A.

    2007-12-01

    this energy spectrum, ruling out non linear effects, may influence the seismic response for future earthquakes. Partial supports from DGAPA-UNAM, Project IN114706, Mexico; from Proyect MCyT CGL2005-05500-C02/BTE, Spain; from project DyETI of INSU-CNRS, France, and from the Instituto Mexicano del Petróleo are greatly appreciated.

  15. The Atlantis Bank gabbro-suite was not a "normal" magma-chamber that produced basalts

    NASA Astrophysics Data System (ADS)

    Kvassnes, A. J.; Dick, H. J. B.; Grove, T. L.

    2003-04-01

    matrix. When clinopyroxene precipitates onto the plagioclase network, the oikocrysts appear more primitive than the original melt that produced the chadacrysts. The oikocryst also become reversely zoned, nucleating on the plagioclase network and growing inward. The resulting melt affected this way will have crystallized Mg-rich clinopyroxene. It is possible that this effect commonly occurs during melt transport in the lower crust and solve the well-known pyroxene paradox previously explained by high-pressure crystallization. If a melt containing dissolved minerals pools, it may be erupted and would result in basalts that appear more primitive than they otherwise would be. The gabbro-suite at Atlantis Bank is not, then, a result of simple fractional crystallization or magma mixing but rather represent part of a complex system of repeated intrusions a mush. Furthermore, if the melts that produced the crust were mantle derived, they fractionated 30-40% elsewhere before they reached the crustal levels sampled in this study and 600+ meters of gabbro exist either below the Hole or in the mantle, though the latter is apparently not required. References: Dick, H. J. B., Ozawa, K., Meyer, P. S., Niu, Y., Robinson, P.T., Constantin, M., Hebert, R., Natland, J. H., Hirth, J. G., Mackie, S. M., 2002. Primary Silicate Mineral Chemistry of a 1.5-km Section of Very Slow Spreading Lower Ocean Crust: ODP Hole 735B, South West Indian Ridge. In: Proceeding of the Ocean Drilling Program, Vol. 176, Scientific Results, Return to Hole 735B, pp 1-60. Elthon, D., Stewart, M., Ross, D. K., 1992. Compositional Trends of Minerals in Oceanic Cumulates. Journal of Geophysical Research, Vol 97, B11, p15,189-15,199. Ghiorso M. S., Sack, R. O., 1995. Chemical Mass Transfer in magmatic Processes IV. A revised and internally consistent thermodynamic model for the interpolation and extrapolation of liquid-solid equilibria in magmatic systems at elevated temperatures and pressures. Cont. Min. Petr., 119, p

  16. Active and Fossil Geothermal Activity at Lake Chapala, Mexico

    NASA Astrophysics Data System (ADS)

    Zârate-del Vall, P.

    2002-12-01

    CPDB values we have two set of data: one near zero (-8.03 to -8.69 \\permil) that means a no contribution of organic carbon and other with low values (-0.35 to -0.75 \\permil) meaning an important contribution of organic carbon; from very low δ 18OPDB values (-8.5 to -0.27 \\permil) we deduced a precipitation in meteoric water with a temperature deposition higher than the surface that matchs with an hydrothermal origin. Mineralogy was confirmed by XRD diffractometry. Near the sub-lacustrine spring "Los Gorgos" there are some small land spots which look like islands (<3-4 m2) made of solid bitumen and which are linked to the bottom of the lake. Because of these hydrocarbon manifestations the company Petróleos Mexicanos drilled (2,348 m deep), without success, an oil exploration well (L¢pez-Ramos, 1979). The characterisation of this solid bitumen is in progress.

  17. Effects of Wind Energy Development on Nesting Ecology of Greater Prairie-Chickens in Fragmented Grasslands

    PubMed Central

    McNew, Lance B; Hunt, Lyla M; Gregory, Andrew J; Wisely, Samantha M; Sandercock, Brett K

    2014-01-01

    ólica sobre la ecología reproductiva de las gallinas en un estudio de 5 años. Ubicamos 59 y 185 nidos antes y después del desarrollo, respectivamente, de una instalación de energía eólica de 201 MW en el hábitat de anidación de las gallinas y estudiamos la selección de sitio de anidación y la supervivencia de nidos en relación con la proximidad a la infraestructura y las condiciones de hábitat. La proximidad con las turbinas no afectó negativamente a la selección de sitios de anidación (β = -0.3, 95% CI = -0.6–0.1). En su lugar, la selección de sitios de anidación y la supervivencia estuvieron fuertemente relacionadas con la cobertura vegetal y otras condiciones locales determinadas por el manejo de la producción de ganado. La integración de los resultados de nuestro proyecto con reportes previos de la evitación conductual de instalaciones de petróleo y gas por otras especies de pastizales sugiere nuevas vías para que la investigación mitigue los impactos del desarrollo energético. PMID:24628394

  18. Cartographic evidence of the disastrous ice flood of 1809 and its aftermath (Danube River, Slovakia).

    NASA Astrophysics Data System (ADS)

    Pišút, P.

    2009-04-01

    The 18th and early 19th century river maps are important data sources for studying past landscapes. This is not only as a result of improved surveying techniques, but also because they depict landscape during probably the most important climatic and land-use changes since the Middle Ages. In this phase of the increased river activity during the last onset of the so-called Little Ice Age period, several major flood events occured. Local manuscript maps, which often depict the channel in major detail, help us to obtain a better understanding of their geomorphic and other impacts. The catastrophic ice flood, which occured on the Middle Danube river at the end of January 1809 was undoubtedly the most disastrous event of its kind in Slovakia, although it also hit a number of settlements in Lower Austria and Hungary. Several people drowned and the flood also resulted in great damage to settlements and livestock. Devastating effects of this flood particularly as to the towns of Bratislava and Komárno/Komárom were comparable with effects of disastrous floods of February 1830 in Vienna (Austria), March 1838 in Buda/Pest (Hungary) or 1845 flood in Prague (Czech Republic), respectively. In case of the present Slovakian capital Bratislava, on January 29, 1809, two ice barriers suddenly rose the water up to 10 m above the zero level and the river quickly overflowed its banks inundating the low-lying parts of the town. The flood blacked out communications with neighbouring regions. Record-breaking height of water led to breaches of the important right-bank embankment (constructed in 1770s). Through several openings water flooded the right bank, almost completely destroying the adjacent village of Petržalka/Engerau. The damage to Vienna highway levee was so massive that it only could be repaired 16 years later, in 1825-6 (although this was also due to Napoleonic wars). The flood also reactivated the Chorvátske rameno anabranch, 33 years after its abandonment. A number of

  19. Phase relations in peralkaline Cl- and F-rich phonolitic melts

    NASA Astrophysics Data System (ADS)

    Giehl, C.; Marks, M.; Nowak, M.

    2013-12-01

    from 800 to 650 °C. These ratios may have the potential for geothermometers, rarely available for peralkaline phase assemblages: log Kd (Mn, Eud/Cpx) = 0.376 * T - 3.858 (n = 7, R2 = 0.94) log Kd (Mn, Ae/Cpx) = 0.292 * T - 2.715 (n = 6, R2 = 0.87) where T = 10000/T (K) and n is the number of experiments used for the fit. References: Giehl C, Marks M, Nowak M (2013) Contrib Mineral Petr 165: 283-304 Marks M, Markl G (2003) Mineral Mag 67: 893-919 Fig. 1: Experimental products at 100 MPa, 700 °C, hydrated starting glass (backscattered electron image): clinopyroxene (Cpx), aenigmatite (Ae), eudialyte (Eud), alkali feldspar (Afs) and residual glass (Gl).

  20. Mystery of Cometary X-Rays Solved

    NASA Astrophysics Data System (ADS)

    2000-07-01

    Massachusetts Institute of Technology's Lincoln Laboratory to search for Earth-approaching objects. In addition to Dr. Lisse, the science team involved with the Chandra observations includes: Drs. Damian Christian (CSC/STScI), Konrad Dennerl (MPE), Frank Marshall, Robert Petre, and Steven Snowden (NASA/GSFC), Harold Weaver (JHU), Brett Stroozas (CEA), and Scott Wolk (CfA) ) The ACIS instrument was built for NASA by the Massachusetts Institute of Technology, Cambridge, and Pennsylvania State University, University Park. NASA's Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program. TRW, Inc., Redondo Beach, Calif., is the prime contractor for the spacecraft. The Smithsonian's Chandra X-ray Center controls science and flight operations from Cambridge, Mass. To follow Chandra's progress, visit the Chandra site at: http://chandra.harvard.edu AND http://chandra.nasa.gov

  1. Geomorphological change detection of fluvial processes of lower Siret channel using LIDAR data

    NASA Astrophysics Data System (ADS)

    Niculita, Mihai; Obreja, Florin; Boca, Bogdan

    2015-04-01

    :121-134. Lague D., Brodu N., Leroux J., 2013. Accurate 3D comparison of complex topography with terrestrial laser scanner: application to the Rangitikei canyon (N-Z), ISPRS journal of Photogrammmetry and Remote Sensing, 80:10-26. James L.A., Hodgson M.E., Ghoshal S., Latiolais M.M., 2012. Geomorphic change detection using historic maps and DEM differencing: the temporal dimension of geospatial analysis. Geomorphology, 137:181-198. Nedelcu G., Borcan M., Branescu E., Petre C., Teleanu B., Preda A., Murafa R., 2011. Exceptional floods from the years 2008 and 2010 in Siret river basin, Proceedings of the Annual Scientific Conference of National Romanian Institute of Hydrology and Water Administration, 1-3 November 2011. (in Romanian) Olariu P., Obreja F., Obreja I., 2009. Some aspects regarding the sediment transit from Trotus catchment and lower sector of Siret river during the exceptional floods from 1991 and 2005, Annals of Stefan cel Mare University of Suceava, XVIII:93-104.(in Romanian) Serbu M., Obreja F., Olariu P., 2009. The 2008 floods from upper Siret catchment. Causes, effects, evaluation, Hidrotechnics, 54(12):1-38. (in Romanian) Wheaton J.M., Brasington J., Darby S., Sear D., 2009. Accounting for uncertainty in DEMs from repeat topographic surveys: improved sediment budgets. Earth Surface Processes and Landforms, 35(2):136-156.

  2. What can zircon ages from the Jack Hills detrital zircon suite really tell us about Hadean geodynamics?

    NASA Astrophysics Data System (ADS)

    Whitehouse, Martin; Nemchin, Alexander

    2015-04-01

    dataset, only 111 grains have been analysed at least twice and of these, only 48 give a consistent internal age, while only 14 have been analysed more than twice and can strictly be considered to yield true ages. Two resulting age peaks at 4.18 - 4.08 Ga and 4.05 - 3.98 Ga potentially represent major magmatic events in the Hadean. In order to explain ages >4.18 Ga, a magmatic event as old as the oldest reliable Jack Hills zircon age of 4.374 Ga is also required. The significance of this limited number of magmatic events for Hadean global geodynamic models will be discussed. References: [1] Harrison, T.M. et al. Geochim Cosmochim Ac 69 (10), A390-A390 (2005), [2] Peck, et al. Geochim Cosmochim Acta 65 (22), 4215-4229 (2001), [3] Kemp, A.I.S. et al. EPSL, 296 (1-2), 45-56 (2010), [4] Kamber, B.S., et al., Contrib Mineral Petr 145 (1), 25-46 (2003), [5] Cavosie, A.J., et al., Precambrian Res 135 (4), 251-279 (2004). [6] Holden P, et al., Int. J. Masspectrometry, 286, 53-63 (2009)

  3. Neoarchean metamorphism recorded in high-precision Sm-Nd isotope systematics of garnets from the Jack Hills (Western Australia)

    NASA Astrophysics Data System (ADS)

    Eccles, K. A.; Baxter, E. F.; Mojzsis, S. J.; Marschall, H.; Williams, M. L.; Jercinovic, M. J.

    2013-12-01

    clean garnet (Sm/Nd ≥ 1.0) and their leached inclusion populations [2]. Four grouped garnet grain separates from one sample yield preliminary dates of 2703.6×6.0Ma, 2612.4×6.0Ma, 2605.0×5.5Ma, and 2567.3×8.3Ma, while the second sample yielded a date of 2579.6×4.6 Ma (2σ). Compositional and geochronologic data indicate likely in situ garnet growth during a late Archean greenschist facies metamorphic event. These dates are generally consistent with published monazite ages placing a metamorphic event at ~ca.2.65Ga [4,5]. It remains possible that an as yet unidentified detrital garnet component is present and may explain some of the scatter in absolute age. [1] Baxter EF, Jordan MK & Inglis JD, 2010, Goldschmidt [2] Baxter EF, Eccles KA & Sullivan N, 2012, Goldschmidt [3] Harvey J & Baxter EF, 2009, Chem Geol, 258, 251-257 [4] Rasmussen B, et al, 2010, Precambrian Res, 180, 26-46 [5] Iizuka T, et al, 2010, Contrib Mineral Petr, 160, 803-823

  4. Combined Sm-Nd and Lu-Hf dating of garnets from the Putomayo foreland basin in south-central Colombia and implications

    NASA Astrophysics Data System (ADS)

    Bloch, E. M.; Ibanez-mejia, M.; Ganguly, J.

    2013-12-01

    , we have made the simplifying assumptions that there was no retention of prograde radiogenic 176Hf in garnet and no rotation of the Lu-Hf Grt-WR isochron during cooling as a result of the somewhat lower closure temperature of Lu compared to that of Hf. Further work is in progress to refine the model taking these effects into account and explore the consequence of using diffusion data from other groups [5, 6]. A review of available experimental REE in garnet diffusion data suggests that low-REE garnets produce diffusion coefficients which are in agreement with [2], while higher-REE garnets produce diffusion coefficients which fall on the Arrhenius trend of [5] and [6]. Because there is no obvious reason why the experimental data presented in [2] or [6] should be erroneous, it is concluded that the variation in these datasets represents a change in diffusion mechanism as a consequence of garnet REE concentration. We hope that the results of this study will help to elucidate the circumstances under which each of these datasets is appropriate. [1] Chakraborty and Ganguly (1992) CMP 111, 74-86. [2] Tirone et al. (2005) Geochim. Cosmochim. Acta 69, 2385-2398. [3] Dodson (1973) CMP 40, 259-274. [4] Ganguly & Tirone, EPSL 170, 131-140. [5] Carlson (2012) Amer. Mineral. 97, 1598-1618. [6] Van Orman et al. (2002) Cont. Min. Petr. 142, 416-424.

  5. Contribution of Tula Refinery flaring emissions to the Mexico megacity

    NASA Astrophysics Data System (ADS)

    Almanza, Victor; Molina, Luisa; Sosa, Gustavo

    2013-04-01

    Flaring is an important source of greenhouse gases, particulate matter and Volatile Organic Compounds (VOCs) in both upstream and downstream operations in the oil and gas industry. In 2010 Mexico was the eleventh emitting country with 2.5 billion cubic meters of gas flared (World Bank, 2012). Black carbon (a component of soot) emissions from flaring facilities are of particular interest because soot is considered a short-lived climate forcer (SLCF) (UNEP, 2011). In 2011 there were 23 megacities of at least 10 million inhabitants. It is expected that this number increase to 37 by 2025, which will include one more in Northern America (NA) and two more in Latin America (UN, 2012). International collaborative projects like MILAGRO in NA and MEGAPOLI/CityZen in Europe, have been conducted to assess the impact of megacities air pollution at several scales. The former focused on the air pollution plume of Mexico City Metropolitan Area (MCMA), the largest megacity in NA. This work studies the contribution of flaring emissions from Tula Refinery to regional air quality. This is accomplished in two steps. First, the flame of a representative sour gas flare is modeled with a CFD combustion code in order to estimate emission rates of combustion by-products of interest for air quality. Mass flow rates of acetylene, ethylene, nitrogen oxides, carbon monoxide, soot and sulfur dioxide are obtained. The emission rates of NO2 and SO2 are compared with measurements obtained at Tula as part of MILAGRO field campaign. The rates of soot, VOCs and CO emissions are compared with estimates obtained by Instituto Mexicano del Petróleo (IMP). The second stage takes the flaring emission rates of the aforementioned species as inputs to WRF-Chem in order to simulate the chemical transport of the plume from 22 March to 27 March of 2006. The air quality model presented reliable performance of the resolved meteorology, with respect to the Mean Absolute Error (MAE), Root Mean Square Error (RMSE

  6. Sudbuction-related tectonic mixing between serpentinized mantle and continental crust in the internal Western Alps: exhumed portion of a marble cake?

    NASA Astrophysics Data System (ADS)

    Spalla, M.; Zucali, M.; Cantù, M.; Roda, M.; Marotta, A.

    2011-12-01

    to individuate the tectonic trajectory of this mantle-crust tectonic assemblage, issued from Alpine subduction. The comparison of this new set of geological data with the prediction of a 2D numerical model, implemented to explore the dynamics of an ocean-continent subduction system (Roda et al., 2010; Roda et al., 2011), allows to detect if the natural metamorphic evolution is compatible with the predicted thermal state of the mantle wedge and to shed light on where and how such type of tectonic mixing can form in the dynamics of a subduction system. Compagnoni R. et al.-1977-Rend.Soc.Ital.Min.Petr.,33,281-334. Meda M., Marotta A.M. & Spalla M.I.-2010-Spec.Pub.Geol.Soc.London,332,149-172. Pognante U.-1989a-Eur.J.Miner.,1,89-104. Pognante U.-1989b-Tectonophysics,162,219-227. Roda M., Marotta A.M. & Spalla M.I.-2010-Geoc.Geoph.Geos.,11,1-21,doi:10.1029/2009GC003015. Roda M., Spalla M.I. & Marotta A.M.-2011-Rend.online Soc.Geol.It.,15,109-112. Spalla M.I. et al.-1996-J.Geodyn.,21,257-285. Zucali M. & Spalla M.I.-2011-J.Struct.Geol.,33,381-398.

  7. Discovery of a Satellite around a Near-Earth Asteroid

    NASA Astrophysics Data System (ADS)

    1997-07-01

    secure lightcurve coverage over a longer period of time than was possible from La Silla alone. As a result, a series of lightcurve measurements were performed from June 3 to 9 in close cooperation with Petr Pravec and Lenka Sarounova working at the Ondrejov Observatory, near Prague in the Czech Republic. Luckily, the weather conditions were favourable at both sites and the dips in the lightcurve were indeed observed at the predicted times. Based on the four well observed events, it was then possible to determine a period of 1.155 days for their occurence. Thus, the hypothesis of a satellite orbiting around Dionysus was confirmed. As a result, the International Astronomical Union's Minor Planet Center located in Cambridge (MA, USA) promptly gave a provisional designation to the new satellite - S/1997 (3671) 1 . How big is Dionysus? Meanwhile, in Hawaii, the world's largest infrared telescope was being trained on Dionysus to obtain information about its size and composition. Alan Harris , also a scientist from the DLR in Berlin, and John Davies from the Joint Astronomy Centre in Hilo, Hawaii, observed the thermal infrared radiation emitted by Dionysus with the 3.8-m United Kingdom Infrared Telescope (UKIRT) situated on Mauna Kea. Similar observations over a broader spectral range were also made by the European Space Agency's orbiting Infrared Space Observatory. The thermal or "heat" radiation emitted by an asteroid depends on its size and the amount of sunlight it absorbs (darker bodies being warmer). In the case of Dionysus the measured radiation was much weaker than expected, indicating that the asteroid has an intrinsically bright (reflective) surface and is only about 1 km in diameter. This is much smaller than (253) Ida, the only other asteroid known to have a moon, which is about 60 km across. Further observations Eventually it should be possible to determine the orbital radius of the satellite, its size and the inclination of its orbital plane. In order to obtain

  8. Sizing up Septoria

    PubMed Central

    Quaedvlieg, W.; Verkley, G.J.M.; Shin, H.-D.; Barreto, R.W.; Alfenas, A.C.; Swart, W.J.; Groenewald, J.Z.; Crous, P.W.

    2013-01-01

    Quaedvlieg, Verkley, W.J. Swart & Crous, Xenobotryosphaeria calamagrostidis Quaedvlieg, Verkley & Crous, Xenoseptoria neosaccardoi Quaedvlieg, H.D. Shin, Verkley & Crous. New combinations - Parastagonospora avenae (A.B. Frank) Quaedvlieg, Verkley & Crous, Parastagonospora nodorum (Berk.) Quaedvlieg, Verkley & Crous, Phaeosphaeria papayae (Speg.) Quaedvlieg, Verkley & Crous, Pseudocercospora domingensis (Petr. & Cif.) Quaedvlieg, Verkley & Crous, Ruptoseptoria unedonis (Roberge ex Desm.) Quaedvlieg, Verkley & Crous, Septorioides pini-thunbergii (S. Kaneko) Quaedvlieg, Verkley & Crous, Sphaerulina abeliceae (Hiray.) Quaedvlieg, Verkley & Crous, Sphaerulina azaleae (Voglino) Quaedvlieg, Verkley & Crous, Sphaerulina berberidis (Niessl) Quaedvlieg, Verkley & Crous, Sphaerulina betulae (Pass.) Quaedvlieg, Verkley & Crous, Sphaerulina cercidis (Fr.) Quaedvlieg, Verkley & Crous, Sphaerulina menispermi (Thüm.) Quaedvlieg, Verkley & Crous, Sphaerulina musiva (Peck) Quaedvlieg, Verkley & Crous, Sphaerulina oxyacanthae (Kunze & J.C. Schmidt) Quaedvlieg, Verkley & Crous, Sphaerulina patriniae (Miura) Quaedvlieg, Verkley & Crous, Sphaerulina populicola (Peck) Quaedvlieg, Verkley & Crous, Sphaerulina quercicola (Desm.) Quaedvlieg, Verkley & Crous, Sphaerulina rhabdoclinis (Butin) Quaedvlieg, Verkley & Crous, Stromatoseptoria castaneicola (Desm.) Quaedvlieg, Verkley & Crous. Typifications: Epitypifications - Phaeosphaeria oryzae I. Miyake, Phaeoseptoria papayae Speg.; Neotypification - Hendersonia paludosa Sacc. & Speg. PMID:24014902

  9. Influence of dissimilatory metal reduction on fate of organic and metal contaminants in the subsurface

    NASA Astrophysics Data System (ADS)

    Lovley, Derek R.; Anderson, Robert T.

    souterrain. Des études d'aquifères pollués par du pétrole ont montré que des micro-organismes réducteurs de fer peuvent être des agents efficaces pour éliminer les hydrocarbures aromatiques des eaux souterraines dans des conditions anérobies. Des études en laboratoire ont montré que des micro-organismes réducteurs de fer avaient la capacité d'éliminer l'uranium d'eaux souterraines polluées. L'activité de micro-organismes réducteurs de fer peut être stimulée de différentes manières pour augmenter l'oxydation de polluants organiques et la réduction de métaux. Des analyses moléculaires concernant des études de terrain et de laboratoire ont montré que des micro-organismes du genre Geobacter deviennent les membres dominants de la communauté microbienne quand les conditions de réduction en Fe(III) sont réalisées à la suite d'une pollution organique, ou lorsque la réduction en Fe(III) est stimulée artificiellement. Ces résultats laissent penser que des connaissances supplémentaires sur l'écophysiologie des espèces Geobacter devraient aider à une meilleure prédiction de la diminution naturelle des teneurs en polluants organiques dans des conditions anérobies, ainsi qu'à la définition de stratégies de dépollution biologique de pollutions souterraines par les métaux. Algunos microorganismos Fe(III)-reductores son capaces de destruir selectivamente determinados contaminantes orgánicos en condiciones anaerobias, oxidándolos a dióxido de carbono. Otros de estos microorganismos Fe(III)-reductores pueden reducir, bien compuestos clorados, bien una gran variedad de metales, que dejan de ser solubles y se inmovilizan en el subsuelo. Estudios realizados en acuéferos contaminados por petróleo muestran que los microorganismos Fe(III)-reductores pueden ser unos agentes muy eficientes para eliminar los hidrocarburos aromáticos de las aguas subterráneas en condiciones anaerobias, mientras que estudios de laboratorio muestran el potencial de estos

  10. Adaptation response surfaces from an ensemble of wheat projections under climate change in Europe

    NASA Astrophysics Data System (ADS)

    Ruiz-Ramos, Margarita; Ferrise, Roberto

    2016-04-01

    (14), Petr Hlavinka(7,8), Frantisek Jurecka(7,8), Jaromir Krzyszczak(10), Marcos Lana(6), Julie

  11. Influence of dissimilatory metal reduction on fate of organic and metal contaminants in the subsurface

    NASA Astrophysics Data System (ADS)

    Lovley, Derek R.; Anderson, Robert T.

    souterrain. Des études d'aquifères pollués par du pétrole ont montré que des micro-organismes réducteurs de fer peuvent être des agents efficaces pour éliminer les hydrocarbures aromatiques des eaux souterraines dans des conditions anérobies. Des études en laboratoire ont montré que des micro-organismes réducteurs de fer avaient la capacité d'éliminer l'uranium d'eaux souterraines polluées. L'activité de micro-organismes réducteurs de fer peut être stimulée de différentes manières pour augmenter l'oxydation de polluants organiques et la réduction de métaux. Des analyses moléculaires concernant des études de terrain et de laboratoire ont montré que des micro-organismes du genre Geobacter deviennent les membres dominants de la communauté microbienne quand les conditions de réduction en Fe(III) sont réalisées à la suite d'une pollution organique, ou lorsque la réduction en Fe(III) est stimulée artificiellement. Ces résultats laissent penser que des connaissances supplémentaires sur l'écophysiologie des espèces Geobacter devraient aider à une meilleure prédiction de la diminution naturelle des teneurs en polluants organiques dans des conditions anérobies, ainsi qu'à la définition de stratégies de dépollution biologique de pollutions souterraines par les métaux. Algunos microorganismos Fe(III)-reductores son capaces de destruir selectivamente determinados contaminantes orgánicos en condiciones anaerobias, oxidándolos a dióxido de carbono. Otros de estos microorganismos Fe(III)-reductores pueden reducir, bien compuestos clorados, bien una gran variedad de metales, que dejan de ser solubles y se inmovilizan en el subsuelo. Estudios realizados en acuéferos contaminados por petróleo muestran que los microorganismos Fe(III)-reductores pueden ser unos agentes muy eficientes para eliminar los hidrocarburos aromáticos de las aguas subterráneas en condiciones anaerobias, mientras que estudios de laboratorio muestran el potencial de estos

  12. Noble Gases in Alpine Gold: U/Th-He Dating and Excesses of Radiogenic He and AR

    NASA Astrophysics Data System (ADS)

    Eugster, O.; Hofmann, B.; Krahenbuhl, U.; Neuenschwander, J.

    1992-07-01

    quantity of trapped atmospheric noble gases we estimate atmospheric ^4He in the gold samples to be three to five orders of magnitude below the observed ^4He concentration. Placer gold is finely distributed in rock material and might be exposed to an alpha-particle irradiation from neighboring U/Th-rich minerals. An alternative He source are inclusions of U/Th-rich minerals, such as zircon, either within the gold material or mechanically worked into the spangles as they were part of the river detritus. Acknowledgement: We thank the Swiss NSF for their support. References: Diamond L.W. (1990) Am. J. of Science 290, 912-958. Schmid K. (1973) Schw. Min. Petr. Mitt. 53, 125-156. Table 1, which in the hard copy appears here, shows concentrations of He, Ne, and Ar (10^-8 cm^3 STP/g) and of K, Th, and U (ppm) in vein-type free gold, placer gold, and quartz. The ^3He and ^21Ne signals were below detection limits, that is ^4He/^3He in gold is >100'000. Average ^20Ne/^22Ne ratios in gold and quartz are 10.2 +- 0.2, that is about 4% larger than in the terrestrial atmosphere. Average ^36Ar/^38Ar = 5.2 +- 0.2 (within errors identical to ^36Ar/^38Ar in air). 1) Sample sizes 50-100 mg. 2) Radiogenic ^40Ar = ^40Ar-295.5 x ^36Ar. 3) Calculated from U/Th and ^40K decay.

  13. Hydrogeology in North America: past and future

    NASA Astrophysics Data System (ADS)

    Narasimhan, T. N.

    2005-03-01

    'hydrogéologie est à la transition entre la volonté de découvrir de nouvelles ressources et l' exploitation la plus bénéfique au possible, et un management judicieux des ressources finies, interconnectées, qui sont vitales pour l' approvisionnement des hommes et autres formes de vie. Le futur de l' hydrogéologie sera dicté par la balance subtile dans laquelle intervient les cycles de l'hydrologie, de l'érosion, de la nutrition, et la décision d'une société technologique qui s'adapterait aux contraintes de la balance, ou qui continuerait d'exploiter les systèmes hydrologiques pour un bénéfice maximum. Par ailleurs il y a une nette tendance à inclure les aspects écologiques, les aspects environnementaux, et les changements humains qui pourraient être influencés par les modifications hydrogéologiques observées depuis une dizaine d'années. Este articulo es una retrospectiva sobre la evolución de la hidrogeología en Norte América en los pasados dos siglos, y una breve especulación de su futuro. La historia de la hidrogeología está marcada por desarrollos en muchos campos diferentes tal como hidrología de aguas subterráneas, mecánica de suelos, ciencia del suelo, geología económica, ingeniería del petróleo, geología estructural, geoquímica, geofísica, geología marina, y más recientemente, ecología. El campo se ha enriquecido por las contribuciones de investigadores distinguidos en todos esos campos. Actualmente, la hidrogeología se encuentra en transición de un estado de descubrir nuevos recursos y explotarlos eficientemente para un beneficio máximo, a un estado de gestión juiciosa de recursos finitos, interconectados, que son vitales para el sustento de humanos y otras cosas vivientes. El futuro de la hidrogeología posiblemente esté determinado por el balance sutil con el cual funcionan los ciclos nutricionales, erosionales e hidrológicos, y la decisión de una sociedad tecnológica para ya sea adaptarse a las restricciones impuestas por el

  14. Phylogenetic lineages in Pseudocercospora

    PubMed Central

    Crous, P.W.; Braun, U.; Hunter, G.C.; Wingfield, M.J.; Verkley, G.J.M.; Shin, H.-D.; Nakashima, C.; Groenewald, J.Z.

    2013-01-01

    .S. Salmon & Wormald) Crous, H.D. Shin & U. Braun, Pseudocercospora hakeae (U. Braun & Crous) U. Braun & Crous, Pseudocercospora leucadendri (Cooke) U. Braun & Crous, Pseudocercospora snelliana (Reichert) U. Braun, H.D. Shin, C. Nakash. & Crous, Pseudocercosporella chaenomelis (Y. Suto) C. Nakash., Crous, U. Braun & H.D. Shin; Typifications: Epitypifications - Pseudocercospora angolensis (T. Carvalho & O. Mendes) Crous & U. Braun, Pseudocercospora araliae (Henn.) Deighton, Pseudocercospora cercidis-chinensis H.D. Shin & U. Braun, Pseudocercospora corylopsidis (Togashi & Katsuki) C. Nakash. & Tak. Kobay., Pseudocercospora dovyalidis (Chupp & Doidge) Deighton, Pseudocercospora fukuokaensis (Chupp) X.J. Liu & Y.L. Guo, Pseudocercospora humuli (Hori) Y.L. Guo & X.J. Liu, Pseudocercospora kiggelariae (Syd.) Crous & U. Braun, Pseudocercospora lyoniae (Katsuki & Tak. Kobay.) Deighton, Pseudocercospora lythri H.D. Shin & U. Braun, Pseudocercospora sambucigena U. Braun, Crous & K. Schub., Pseudocercospora stephanandrae (Tak. Kobay. & H. Horie) C. Nakash. & Tak. Kobay., Pseudocercospora viburnigena U. Braun & Crous, Pseudocercosporella chaenomelis (Y. Suto) C. Nakash., Crous, U. Braun & H.D. Shin, Xenostigmina zilleri (A. Funk) Crous; Lectotypification - Pseudocercospora ocimicola (Petr. & Cif.) Deighton; Neotypifications - Pseudocercospora kiggelariae (Syd.) Crous & U. Braun, Pseudocercospora lonicericola (W. Yamam.) Deighton, Pseudocercospora zelkovae (Hori) X.J. Liu & Y.L. Guo. PMID:24014898

  15. Adaptation response surfaces from an ensemble of wheat projections under climate change in Europe

    NASA Astrophysics Data System (ADS)

    Ruiz-Ramos, Margarita; Ferrise, Roberto

    2016-04-01

    (14), Petr Hlavinka(7,8), Frantisek Jurecka(7,8), Jaromir Krzyszczak(10), Marcos Lana(6), Julien Minet(15), Manuel Montesino(16), Claas Nendel(6), John Porter(16), Jaime Recio(1), Françoise Ruget(11), Alberto Sanz(1), Zacharias Steinmetz(17,18), Pierre Stratonovitch(19), Iwan Supit(20), Domenico Ventrella(21), Allard de Wit(20) and Reimund P. Rötter(4). 1 Universidad Politecnica de Madrid, ETSIAgrónomos,28040 Madrid, Spain, margarita.ruiz.ramos@upm.es 2 University of Florence, 50144 Florence, Italy 3 IFAPA Junta de Andalucia, 14004 Córdoba, Spain 4 Natural Resources Institute (LUKE), 01370 Vantaa, Finland 5 Finnish Environment Institute (SYKE), 00250 Helsinki, Finland 6 Leibniz Centre for Agricultural Landscape Research (ZALF), 15374 Müncheberg, Germany 7 Institute of Agrosystems and Bioclimatology, Mendel University in Brno, Brno 613 00, Czech Republic 8 Global Change Research Institute CAS, 603 00 Brno, Czech Republic 9 INRES, University of Bonn, 53115 Bonn, Germany 10 Institute of Agrophysics Polish Academy of Sciences, Lublin, Poland 11 INRA, UMR 1114 EMMAH, F-84914 Avignon, France 12 James Hutton Institute, Invergowrie, Dundee, DD2 5DA, Scotland 13 State Key Laboratory of Earth Surface Processes and Resource Ecology, Academy of Disaster Reduction and Emergency Management, Beijing Normal University, Beijing 100875, China 14 University of Sassari, 07100 Sassari, Italy 15 Université de Liège, 4000 Liège, Belgium 16 University of Copenhagen, 2630 Taastrup, Denmark 17 RIFCON GmbH, 69493 Hirschberg, Germany 18 Group of Environmental and Soil Chemistry, Institute for Environmental Sciences, University of Koblenz-Landau, 76829 Landau, Germany 19 Rothamsted Research, Harpenden, Herts, AL5 2JQ, UK 20 Wageningen University, 6700AA Wageningen, The Netherlands 21 Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria. CRA-SCA

  16. PREFACE: Eighth International Conference on Dissociative Recombination (DR2010)

    NASA Astrophysics Data System (ADS)

    Guberman, Steven L.; Orel, Ann E.

    2011-07-01

    Lake Louise, Alberta, Canada in May, 1988 [2] and was followed in May 1992 [3] at L'Abbaye de Saint Jacut de la Mer, Brittany, France, in May, 1995 [4] at Ein Gedi, Israel, in June 1999 [5] on the island of Nässlingen in the Stockholm archipelago, Sweden, in August, 2001 [6] at Chicago, USA, in July, 2004 [7] at the Alte Mälzerei, Mosbach, Germany and in July, 2007 [8] at the Resort d'Amelander Kaap on the island of Ameland, The Netherlands. All papers from the last two conferences and this conference are freely available at http://iopscience.iop.org/1742-6596. In keeping with the tradition of prior DR conferences, all papers in this volume have been refereed. Our thanks go to the referees for their efforts. Travel support for conference participants was provided by NSF grant ATM-0838061 and NASA grant NNX09AQ73G to SLG. We thank Priscilla Kujawski for proofreading the Dedication. Steven L GubermanAnn E OrelEditors Conference photograph Participants of the 8th International Conference on Dissociative Recombination: Theory, Experiments and Applications. 1. Stephen Pratt18. Randy Vane35. Robert Continetti 2. Chris Greene19. Claude Krantz36. Henrik Buhr 3. Bastiaan Braams20. Xavier Urbain37. Mats Larsson 4. Ed Grant21. Hidekazu Takagi38. Dirk Schwalm 5. Christian Nordhorn22. Brian Mitchell39. Evelyne Roueff 6. Steen Brønsted Nielsen23. Andreas Wolf40. Pascal Pernot 7. Dermot Madden24. Daren Stotler41. Stefan Rosén 8. Radek Plašil25. Slava Kokoouline42. Rainer Johnsen 9. Daniel Savin26. David Schultz43. Xiaohong Cai 10. Jonathan Tennyson27. Mourad Telmini44. Dan Haxton 11. Peet Hickman28. Ruth Malenda45. Åsa Larson 12. Michael Fogle29. Slim Chourou46. Dahbia Talbi 13. Waffeu Tamo Francois Oliver30. Petr Dohnal47. Ann Orel 14. Christian Jungen31. Julia Stützel48. Steven Guberman 15. Ilya Fabrikant32. Ioan Schneider49. Jane Fox 16. Wolf Geppert33. Nicholas Shuman50. Richard Thomas 17. Oldřich Novotný34. Holger Kreckel51. Fangfang Ruan

  17. Hydrogeology in North America: past and future

    NASA Astrophysics Data System (ADS)

    Narasimhan, T. N.

    2005-03-01

    'hydrogéologie est à la transition entre la volonté de découvrir de nouvelles ressources et l' exploitation la plus bénéfique au possible, et un management judicieux des ressources finies, interconnectées, qui sont vitales pour l' approvisionnement des hommes et autres formes de vie. Le futur de l' hydrogéologie sera dicté par la balance subtile dans laquelle intervient les cycles de l'hydrologie, de l'érosion, de la nutrition, et la décision d'une société technologique qui s'adapterait aux contraintes de la balance, ou qui continuerait d'exploiter les systèmes hydrologiques pour un bénéfice maximum. Par ailleurs il y a une nette tendance à inclure les aspects écologiques, les aspects environnementaux, et les changements humains qui pourraient être influencés par les modifications hydrogéologiques observées depuis une dizaine d'années. Este articulo es una retrospectiva sobre la evolución de la hidrogeología en Norte América en los pasados dos siglos, y una breve especulación de su futuro. La historia de la hidrogeología está marcada por desarrollos en muchos campos diferentes tal como hidrología de aguas subterráneas, mecánica de suelos, ciencia del suelo, geología económica, ingeniería del petróleo, geología estructural, geoquímica, geofísica, geología marina, y más recientemente, ecología. El campo se ha enriquecido por las contribuciones de investigadores distinguidos en todos esos campos. Actualmente, la hidrogeología se encuentra en transición de un estado de descubrir nuevos recursos y explotarlos eficientemente para un beneficio máximo, a un estado de gestión juiciosa de recursos finitos, interconectados, que son vitales para el sustento de humanos y otras cosas vivientes. El futuro de la hidrogeología posiblemente esté determinado por el balance sutil con el cual funcionan los ciclos nutricionales, erosionales e hidrológicos, y la decisión de una sociedad tecnológica para ya sea adaptarse a las restricciones impuestas por el

  18. Rapid high-silica magma generation in basalt-dominated rift settings

    NASA Astrophysics Data System (ADS)

    Berg, Sylvia E.; Troll, Valentin R.; Burchardt, Steffi; Deegan, Frances M.; Riishuus, Morten S.; Whitehouse, Martin J.; Harris, Chris; Freda, Carmela; Ellis, Ben S.; Krumbholz, Michael; Gústafsson, Ludvik E.

    2015-04-01

    crustal recycling as a key process. Our results therefore provide a mechanism and a time-scale for rapid, voluminous silicic magma generation in modern and ancient basalt-dominated rift setting, such as Afar, Taupo, and potentially early Earth. The Neogene plume-related rift flank setting of NE-Iceland may thus constitute a plausible geodynamic and compositional analogue for generating silicic (continental) crust in the subduction-free setting of a young Earth (e.g. ≥3 Ga [14]). [1] Bunsen, R. 1851. Ann. Phys. Chem. 159, 197-272. [2] MacDonald R., et al., 1987. Mineral. Mag. 51, 183-202. [3] Jonasson, K., 2007. J. Geodyn. 43, 101-117. [4] Martin, E., et al., 2011. Earth Planet. Sci. Lett. 311, 28-38. [5] Charreteur, G., et al., 2013.Contrib. Mineral. Petr. 166, 471- 490. [6] Willbold, E., et al., 2009. Earth Planet. Sci. Lett. 279, 44-52. [7] Reimink, J.R., et al., 2014. Nat. Geosci. 7, 529-533. [8] Gústafsson, L.E., et al., 1989. Jökull 39, 75-89. [9] Meade, F.C., et al., 2014. Nat. comm. 5. [10] Óskarsson, B.V., Riishuus, M.S., 2013. J. Volcanol. Geoth. Res. 267, 92-118. [11] Carley, T.L., et al., 2014. Earth Planet. Sci. Lett. 405, 85-97. [12] Trail, D., et al., 2007. Geochem. Geophys. Geosyst.8, Q06014. [13] Harrison, T.M. et al., 2008. Earth Planet. Sci. Lett.268, 476-486. [14] Kamber, B. S., et al., 2005. Earth Planet. Sci. Lett. 240, 276-290.

  19. PREFACE: XIV International Conference on Calorimetry in High Energy Physics

    NASA Astrophysics Data System (ADS)

    Wang, Yifang

    2011-03-01

    H KAVATSYUK, MyroslavKVI, University of Groningen KHRAMOV, EvgenyJoint Institute for Nuclear Research KISTENEV, EdouardBrookhaven National Laboratory KUO, Chia MingNCU KWON, YoungilYonsei University LAKTINEH, ImadIPNL LECOQ, PaulCERN LI, ChengUniversity of Science and Technology of China LI, NingboNanJing Normal University & IHEP LI, WeidongIHEP LI, WeiguoIHEP LIU, ChunxiuIHEP LIU, LijiaoUniversity of Bergen, Norway LIVAN, MicheleDipartimento di Fisica Nucleare e Teorica, University di Pavia , Italy LU, JunguangIHEP LUBRANO, PasqualeINFN Sezione di Perugia MACHIKHILIYAN, IrinaLAPP, Annecy, France MAVROMANOLAKIS, GeorgiosCERN MILLER, David WSLAC and Stanford University NECESAL, PetrInstitute of Physics AS CR, v.v.i. NEMECEK, StanislavFZU AVCR Praha NIESS, ValentinLPC, Clermont (CNRS/IN2P3) NOVOTNY, Rainer W2nd Physics Institute, University Giessen, Germany OBERLACK, HorstMPI für Physik, Munich PARA, AdamFermilab PARAMATTI, RiccardoINFN Rome & CERN PEPE, MonicaINFN Perugia POSPELOV, GennadyMax-Planck-Institut für Physik REPOND, JoseArgonne National Laboratory ROSSETTI, ValerioIFAE - Barcelona SCHACHT, PeterMPI/Munich SEFKOW, FelixDESY SFYRLA, AnnaCERN SGUAZZONI, GiacomoINFN Section of Florence SIMON, FrankMax-Planck-Institute for Physics SIMONYAN, MargarNiels Bohr Institute, Copenhagen University SPADARO, TommasoLNF INFN SUN, XileiIHEP TAKESHITA, TohruShinshu University TANG, ZeboUniversity of Science and Technology of China TAPAN, IlhanUludag University THEOFILATOS, KonstantinosETH Zurich THOMSON, MarkUniversity of Cambridge TOKUNO, HisaoDepartment of Physics, Graduate School of Science and Engineering TRONCON, ClaraINFN UOZUMI SatoruKyungpook National University USAI, GiulioUniversity of Texas at Arlington VAZQUEZ GOMEZ, RicardoUniversitat de Barcelona VIDEAU, HenriLLR - Ecole polytechnique VOLOBOUEV, IgorTexas Tech University WAN, RenzhuoIOPP-CCNU, Wuhan, China & IPHC-CNRS, Strasbourg, France WANG, ZhengIHEP WANG, ZhigangIHEP WENZEL, HansFermilab WIGMANS, RichardTexas Tech

  20. Water-gas dynamics and coastal land subsidence over Chioggia Mare field, northern Adriatic Sea

    NASA Astrophysics Data System (ADS)

    Teatini, Pietro; Baú, Domenico; Gambolati, Giuseppe

    2000-09-01

    menace potentielle pour la ville de Venise, à 25 km au nord-ouest du centre de Chioggia Mare. Afin d'évaluer le risque de subsidence du sol provoquée par les prélèvements de gaz, un modèle numérique a été développé pour prévoir la compaction des formations réservoirs de gaz en même temps que celle de l'aquifère latéral et sous-jacent, par effet de drainance, sur une période de 13 ans de production, suivie de 12 ans, et pour prévoir le transfert de la compaction profonde jusqu'à la surface du sol. Afin de prendre en compte l'incertitude sur un petit nombre de paramètres hydromécaniques importants, plusieurs scénarios ont été simulés et les prévisions les plus pessimistes ont été obtenues. Les résultats de la modélisation montrent qu'on doit s'attendre, au cours des 25 ans, au plus à une subsidence du sol de 1 cm à Chioggia, tandis que Venise ne subira aucun effet. Si la baisse de l'aquifère est compensée par une injection d'eau, la subsidence du sol s'arrêtera à 5 km au large et la zone côtière de Chioggia subira un effet de 0,6 à 0,7 cm. Resumen. Recientemente, la compañía nacional italiana del petróleo, ENI-Agip, ha enviado al Ministerio de Medio Ambiente de Italia (Comité VIA) un gran programa de desarrollo de 15 campos de gas en el norte del Mar Adriático para la evaluación de su impacto medioambiental. Una de las reservas principales de gas se halla en el mar de Chioggia, a unos 10 km mar adentro de la costa veneciana, a una profundidad de entre 1.000 y 1.400 m. Se espera que la producción en este campo produzca un impacto en la estabilidad de la línea de costa, y que suponga una amenaza potencial para la ciudad de Venecia, situada a 25 km al noroeste de la explotación. Se desarrolló un modelo numérico para evaluar el riesgo de subsidencia debido a la extracción de gas a lo largo de los 13 años de producción y del período post-productivo de 12 años. Sus predicciones indican que se causará la compactación tanto