Science.gov

Sample records for institutului politehnic din

  1. Diné (Navajo) Ethno- and Archaeoastronomy

    NASA Astrophysics Data System (ADS)

    Chamberlain, Von Del

    The Navajo (Diné) are an Athabascan-speaking people who migrated from the far northwest of America into the desert southwest where they became the largest surviving Native American culture. Three words portray Diné philosophy - beauty, harmony, and balance. Their traditions are rich with astronomical symbolism found in literature, ceremony, iconography, artifacts, rock art, and the sacred landscape. This chapter summarizes Diné astronomical traditions, identification of stars known to be important to the Diné, and how these are depicted on artifacts and rock art.

  2. Concept analysis of Diné Hózhó: a Diné wellness philosophy.

    PubMed

    Kahn-John, Michelle

    2010-01-01

    American Indian Alaska Native people of the United States face challenges in attaining physical, mental, spiritual, and environmental health. This article presents a concept analysis of Diné Hózhó, a complex and misunderstood wellness concept the Diné (Navajo) strive to attain. Findings from a literature review are presented to explore anthropological definitions and uses of the concept Hózhó. The method of concept analysis of Walker and Avant is utilized, model cases are presented. Recommendations for application in nursing practice are presented. PMID:20460958

  3. Ernst Rüdin: Hitler's Racial Hygiene Mastermind.

    PubMed

    Joseph, Jay; Wetzel, Norbert A

    2013-01-01

    Ernst Rüdin (1874-1952) was the founder of psychiatric genetics and was also a founder of the German racial hygiene movement. Throughout his long career he played a major role in promoting eugenic ideas and policies in Germany, including helping formulate the 1933 Nazi eugenic sterilization law and other governmental policies directed against the alleged carriers of genetic defects. In the 1940s Rüdin supported the killing of children and mental patients under a Nazi program euphemistically called "Euthanasia." The authors document these crimes and discuss their implications, and also present translations of two publications Rüdin co-authored in 1938 showing his strong support for Hitler and his policies. The authors also document what they see as revisionist historical accounts by leading psychiatric genetic authors. They outline three categories of contemporary psychiatric genetic accounts of Rüdin and his work: (A) those who write about German psychiatric genetics in the Nazi period, but either fail to mention Rüdin at all, or cast him in a favorable light; (B) those who acknowledge that Rüdin helped promote eugenic sterilization and/or may have worked with the Nazis, but generally paint a positive picture of Rüdin's research and fail to mention his participation in the "euthanasia" killing program; and (C) those who have written that Rüdin committed and supported unspeakable atrocities. The authors conclude by calling on the leaders of psychiatric genetics to produce a detailed and complete account of their field's history, including all of the documented crimes committed by Rüdin and his associates. PMID:23180223

  4. [Ernst Rüdin: distinguished scientist, radical racial hygienist].

    PubMed

    Roelcke, V

    2012-03-01

    Ernst Rüdin (1874–1952) was one of the founders of psychiatric genetics. From 1931 until 1945, he was Director of the German Institute for Psychiatric Research (Deutsche Forschungsanstalt für Psychiatrie, DFA) and from 1935 until 1945 President of the German Association of Neurologists and Psychiatrists. The historical knowledge on Rüdin is reconsidered, using new sources, and with a focus on Rüdin’s involvement in the Nazi program of patient killings („euthanasia"). It is documented that (1) it is a misconception to interpret psychiatric genetics as „instrumentalised" by the Nazi regime; (2) Rüdin belonged to the group of psychiatric perpetrators who worked to give the Nazi selection policies scientific authority; (3) Rüdin knew early on about the patient killings and refused to support others in their efforts to stop them; and (4) the research in the context of the patient killings carried out by Julius Deussen, a member of Rüdin’s team at the DFA, was initiated and actively supported by Rüdin, and co-financed by the DFA.

  5. Dinámica de objetos transplutonianos: resultados preliminares

    NASA Astrophysics Data System (ADS)

    Fernández, S.; Brizuela, H.; Roig, F.; Varela, O.

    Se presentan los resultados de una integración numérica de las ecuaciones de movimiento para objetos transplutonianos. Se han calculado los tiempos de Lyapunov para esos objetos y se analiza el comportamiento dinámico de los mismos.

  6. DInSAR fringes simulation of sandbox models

    NASA Astrophysics Data System (ADS)

    Derron, Marc-Henri; Carrea, Dario; Michoud, Clément; Jaboyedoff, Michel

    2015-04-01

    Interpreting satellite DInSAR patterns of slope movements can be difficult because of unwrapping problems, loss of coherence or radar imaging geometry limitations (layover, shadowing …). We investigate the potential of simulating interferometric fringes as a tool to help understanding real DInSAR images. Various types of gravitational slope deformations (sliding, toppling …) have been produced in a sandbox in the lab. These experiments were monitored with a micro-lidar Minolta-Konika Vivid 9i to get successive Digital Elevation Models of the surface. A pair of DEM is then used to simulate DInSAR fringes patterns, with the possibility to vary the wavelength, the angle between the line of sight and the ground displacement, the look angle, the baseline, etc. DInSAR fringes simulated here are idealized. They are not affected by any noise, decoherence, layover or shadow effects; radar image deformations are computed in ancillary files. However it appears that even these ideal wrapped fringes patterns get rapidly very complex when deformation is strong. Then this kind of tool is of interest to better constrain ground surface deformations from resulting InSAR fringes (from lab models or real landslides data). It makes also possible to test how the acquisition geometry impacts the InSAR result depending on the type of slope movement considered.

  7. Doctor Shoja-ad-Din Sheikholeslamzadeh and his Achievements

    PubMed Central

    Afshar, Ahmadreza; Ziaei, Majid Eyvaz; Ahmadi, Aziz

    2015-01-01

    Doctor Shoja-ad-Din Sheikholeslamzadeh (also known as Dr. Sheikh) (1931-2014) was an outstanding orthopedic surgeon. He is credited for the establishment of the Iranian Association of Rehabilitation, Shafa Yahyaian Hospital as an Orthopedic and Rehabilitation Center, the Social Welfare Organization, Iran's emergency dispatch center (115) and many other major projects that led to the upgrading of health care services in Iran. He also served as the Minister of Social Welfare and Minister of Health and Welfare before the Islamic revolution. The history of modern health care management and modern orthopedic surgery in Iran are indebted to the great leadership and executive abilities of Dr. Sheikh. PMID:25692161

  8. An efficient compressive sensing based PS-DInSAR method for surface deformation estimation

    NASA Astrophysics Data System (ADS)

    Li, J. T.; Xu, H. P.; Shan, L.; Liu, W.; Chen, G. Z.

    2016-11-01

    Permanent scatterers differential interferometric synthetic aperture radar (PS-DInSAR) is a technique for detecting surface micro-deformation, with an accuracy at the centimeter to millimeter level. However, its performance is limited by the number of SAR images available (normally more than 20 are needed). Compressive sensing (CS) has been proven to be an effective signal recovery method with only a very limited number of measurements. Applying CS to PS-DInSAR, a novel CS-PS-DInSAR method is proposed to estimate the deformation with fewer SAR images. By analyzing the PS-DInSAR process in detail, first the sparsity representation of deformation velocity difference is obtained; then, the mathematical model of CS-PS-DInSAR is derived and the restricted isometry property (RIP) of the measurement matrix is discussed to validate the proposed CS-PS-DInSAR in theory. The implementation of CS-PS-DInSAR is achieved by employing basis pursuit algorithms to estimate the deformation velocity. With the proposed method, DInSAR deformation estimation can be achieved by a much smaller number of SAR images, as demonstrated by simulation results.

  9. A ΔdinB mutation that sensitizes Escherichia coli to the lethal effects of UV and X-radiation

    PubMed Central

    Lee, Mei-Chong W.; Franco, Magdalena; Vargas, Doris M.; Hudman, Deborah A.; White, Steven J.; Fowler, Robert G.; Sargentini, Neil J.

    2014-01-01

    The DinB (PolIV) protein of Escherichia coli participates in several cellular functions. We investigated a dinB mutation, Δ(dinB-yafN)883(::kan) [referred to as ΔdinB883], which strongly sensitized E. coli cells to both UV- and X-radiation killing. Earlier reports indicated dinB mutations had no obvious effect on UV radiation sensitivity which we confirmed by showing that normal UV radiation sensitivity is conferred by the ΔdinB749 allele. Compared to a wild-type strain, the ΔdinB883 mutant was most sensitive (160-fold) in early to mid-logarithmic growth phase and much less sensitive (twofold) in late log or stationary phases, thus showing a growth phase-dependence for UV radiation sensitivity. This sensitizing effect of ΔdinB883 is assumed to be completely dependent upon the presence of UmuDC protein; since the ΔdinB883 mutation did not sensitize the ΔumuDC strain to UV radiation killing throughout log phase and early stationary phase growth. The DNA damage checkpoint activity of UmuDC was clearly affected by ΔdinB883 as shown by testing a umuC104 ΔdinB883 double-mutant. The sensitivities of the ΔumuDC strain and the ΔdinB883 ΔumuDC double-mutant strain were significantly greater than for the ΔdinB883 strain, suggesting that the ΔdinB883 allele only partially suppresses UmuDC activity. The ΔdinB883 mutation partially sensitized (fivefold) uvrA and uvrB strains to UV radiation, but did not sensitize a ΔrecA strain. A comparison of the DNA sequences of the ΔdinB883 allele with the sequences of the Δ(dinB-yafN)882(::kan) and ΔdinB749 alleles, which do not sensitize cells to UV radiation, revealed ΔdinB883 is likely a “gain-of-function” mutation. The ΔdinB883 allele encodes the first 54 amino acids of wild-type DinB followed by 29 predicted residues resulting from the continuation of the dinB reading frame into an adjacent insertion fragment. The resulting polypeptide is proposed to interfere directly or indirectly with UmuDC function

  10. On the update of DIN-2PI spectrometer

    SciTech Connect

    Novikov, A. G. Puchkov, A. V.

    2011-12-15

    The prospects of increasing the resolution of the DIN-2PI spectrometer at initial neutron energies of 50-500 meV are discussed. The spectrometer resolution can be significantly improved using time-of-flight neutron monochromatization supplemented with a monochromator crystal. The application of this combined monochromatization technique makes the dependence that the instrumental resolution has on the duration of the neutron pulse from the IBR-2 reactor insignificant. This update will make it possible to perform experiments with initial neutron energies to several hundreds of meV in the energy-dumping mode, which, in turn, allows one to study condensed media in a wide range of temperatures, including cryogenic.

  11. Solution structure of DinI provides insight into its mode of RecA inactivation.

    PubMed Central

    Ramirez, B. E.; Voloshin, O. N.; Camerini-Otero, R. D.; Bax, A.

    2000-01-01

    The Escherichia coli RecA protein triggers both DNA repair and mutagenesis in a process known as the SOS response. The 81-residue E. coli protein DinI inhibits activity of RecA in vivo. The solution structure of DinI has been determined by multidimensional triple resonance NMR spectroscopy, using restraints derived from two sets of residual dipolar couplings, obtained in bicelle and phage media, supplemented with J couplings and a moderate number of NOE restraints. DinI has an alpha/beta fold comprised of a three-stranded beta-sheet and two alpha-helices. The beta-sheet topology is unusual: the central strand is flanked by a parallel and an antiparallel strand and the sheet is remarkably flat. The structure of DinI shows that six negatively charged Glu and Asp residues on DinI's kinked C-terminal alpha-helix form an extended, negatively charged ridge. We propose that this ridge mimics the electrostatic character of the DNA phospodiester backbone, thereby enabling DinI to compete with single-stranded DNA for RecA binding. Biochemical data confirm that DinI is able to displace ssDNA from RecA. PMID:11152126

  12. Mycobacterium tuberculosis DinG Is a Structure-specific Helicase That Unwinds G4 DNA

    PubMed Central

    Thakur, Roshan Singh; Desingu, Ambika; Basavaraju, Shivakumar; Subramanya, Shreelakshmi; Rao, Desirazu N.; Nagaraju, Ganesh

    2014-01-01

    The significance of G-quadruplexes and the helicases that resolve G4 structures in prokaryotes is poorly understood. The Mycobacterium tuberculosis genome is GC-rich and contains >10,000 sequences that have the potential to form G4 structures. In Escherichia coli, RecQ helicase unwinds G4 structures. However, RecQ is absent in M. tuberculosis, and the helicase that participates in G4 resolution in M. tuberculosis is obscure. Here, we show that M. tuberculosis DinG (MtDinG) exhibits high affinity for ssDNA and ssDNA translocation with a 5′ → 3′ polarity. Interestingly, MtDinG unwinds overhangs, flap structures, and forked duplexes but fails to unwind linear duplex DNA. Our data with DNase I footprinting provide mechanistic insights and suggest that MtDinG is a 5′ → 3′ polarity helicase. Notably, in contrast to E. coli DinG, MtDinG catalyzes unwinding of replication fork and Holliday junction structures. Strikingly, we find that MtDinG resolves intermolecular G4 structures. These data suggest that MtDinG is a multifunctional structure-specific helicase that unwinds model structures of DNA replication, repair, and recombination as well as G4 structures. We finally demonstrate that promoter sequences of M. tuberculosis PE_PGRS2, mce1R, and moeB1 genes contain G4 structures, implying that G4 structures may regulate gene expression in M. tuberculosis. We discuss these data and implicate targeting G4 structures and DinG helicase in M. tuberculosis could be a novel therapeutic strategy for culminating the infection with this pathogen. PMID:25059658

  13. Manufacturing of microcomponents in a research institute under DIN EN ISO 9001

    NASA Astrophysics Data System (ADS)

    Maas, Dieter; Karl, Bernhard; Saile, Volker; Schulz, Joachim

    2000-08-01

    The Institute for Microstructure Technology at Forschungszentrum Karlsruhe has implemented a rigorous quality management system and was certified according to the DIN ISO EN 9001 standard in January 2000.

  14. Developing a salinity-based approach for the evaluation of DIN removal rate in estuarine ecosystems.

    PubMed

    Hong, Yiguo; Wang, Shuailong; Xu, Xiang-Rong; Wu, Jiapeng; Liu, Ling; Yue, Weizhong; Wu, Meilin; Wang, Youshao

    2015-10-01

    Estuaries play an important role in the removal of overloading nitrogen to relieve the eutrophic pressure of coastal seawater. However, the exact amount of nitrogen removed in estuarine ecosystems is difficult to be estimated because of the complex dynamic mixing process between riverine water and coastal seawater. In this study, a new method was developed to calculate the removal rate of dissolved inorganic nitrogen (DIN) in estuarine waters attributed to the mixing process and was based on the assumption that relative salinity can serve as an indicator of the degree of mixing. This assumption was supported by the experimental results that demonstrated a linear regression relationship between DIN decline and salinity increase Thus, the decreased amount of DIN in mixing waters attributed to the dilution effect could be determined with the salinity as an index. With this model, the DIN removal rate in both Chesapeake Bay and Pearl River Estuary were defined. As predicted, our analysis demonstrated that the DIN removal rate increased gradually from upstream to downstream in both studied estuaries with obvious seasonable variation pattern: high in warm seasons and low in cold seasons. The practical application of this method might be affected by multiple factors, including the geographic landform of estuaries, initial estuaries DIN concentration, the DIN concentration in seawater, DIN importing from tributaries, sewage discharge and hydrodynamic mixing. Therefore, the results supported the hypothesis that estuaries have a strong capability to remove the nitrogen inputted from human activities, especially in warm season and therefore should play an important role in regulating the balance of global nitrogen biogeochemical cycle. PMID:25957975

  15. Developing a salinity-based approach for the evaluation of DIN removal rate in estuarine ecosystems.

    PubMed

    Hong, Yiguo; Wang, Shuailong; Xu, Xiang-Rong; Wu, Jiapeng; Liu, Ling; Yue, Weizhong; Wu, Meilin; Wang, Youshao

    2015-10-01

    Estuaries play an important role in the removal of overloading nitrogen to relieve the eutrophic pressure of coastal seawater. However, the exact amount of nitrogen removed in estuarine ecosystems is difficult to be estimated because of the complex dynamic mixing process between riverine water and coastal seawater. In this study, a new method was developed to calculate the removal rate of dissolved inorganic nitrogen (DIN) in estuarine waters attributed to the mixing process and was based on the assumption that relative salinity can serve as an indicator of the degree of mixing. This assumption was supported by the experimental results that demonstrated a linear regression relationship between DIN decline and salinity increase Thus, the decreased amount of DIN in mixing waters attributed to the dilution effect could be determined with the salinity as an index. With this model, the DIN removal rate in both Chesapeake Bay and Pearl River Estuary were defined. As predicted, our analysis demonstrated that the DIN removal rate increased gradually from upstream to downstream in both studied estuaries with obvious seasonable variation pattern: high in warm seasons and low in cold seasons. The practical application of this method might be affected by multiple factors, including the geographic landform of estuaries, initial estuaries DIN concentration, the DIN concentration in seawater, DIN importing from tributaries, sewage discharge and hydrodynamic mixing. Therefore, the results supported the hypothesis that estuaries have a strong capability to remove the nitrogen inputted from human activities, especially in warm season and therefore should play an important role in regulating the balance of global nitrogen biogeochemical cycle.

  16. The Escherichia coli SOS gene dinF protects against oxidative stress and bile salts.

    PubMed

    Rodríguez-Beltrán, Jerónimo; Rodríguez-Rojas, Alexandro; Guelfo, Javier R; Couce, Alejandro; Blázquez, Jesús

    2012-01-01

    DNA is constantly damaged by physical and chemical factors, including reactive oxygen species (ROS), such as superoxide radical (O(2)(-)), hydrogen peroxide (H(2)O(2)) and hydroxyl radical (•OH). Specific mechanisms to protect and repair DNA lesions produced by ROS have been developed in living beings. In Escherichia coli the SOS system, an inducible response activated to rescue cells from severe DNA damage, is a network that regulates the expression of more than 40 genes in response to this damage, many of them playing important roles in DNA damage tolerance mechanisms. Although the function of most of these genes has been elucidated, the activity of some others, such as dinF, remains unknown. The DinF deduced polypeptide sequence shows a high homology with membrane proteins of the multidrug and toxic compound extrusion (MATE) family. We describe here that expression of dinF protects against bile salts, probably by decreasing the effects of ROS, which is consistent with the observed decrease in H(2)O(2)-killing and protein carbonylation. These results, together with its ability to decrease the level of intracellular ROS, suggests that DinF can detoxify, either direct or indirectly, oxidizing molecules that can damage DNA and proteins from both the bacterial metabolism and the environment. Although the exact mechanism of DinF activity remains to be identified, we describe for the first time a role for dinF. PMID:22523558

  17. Dinámica de planetas extrasolares resonantes

    NASA Astrophysics Data System (ADS)

    Beauge, C.

    Actualmente se han detectado 117 planetas alrededor de estrellas de Secuencia Principal, incluyendo 12 sistemas planetarios, cada uno con dos o tres miembros. De estos últimos, ocho poseen planetas en órbitas próximas y sus perturbaciones gravitacionales se convierten en un factor fundamental para la estabilidad orbital del sistema. Todos se encuentran en configuraciones resonantes, desde la conmensurabilidad de movimientos 2/1 de Gliese 876, hasta la resonancia secular de Ups And. En esta presentación analizamos varios aspectos de la dinámica resonante de los planetas extrasolares, incluyendo la existencia de soluciones de equilibrio, construcción de modelos analógicos y métodos para la determinación de masas individuales. También discutimos por qué las resonancias son tan frecuentes en estos sistemas, comparado con nuestro propio Sistema Solar. Por último, intentamos relacionar estos modelos con la hipótesis de migración planetaria, buscando límites en su extensión y en los posibles mecanismos que le dieron origen.

  18. The Diné Educational Philosophy (DEP) and its incorporation into the Associate of Science Degree Program in Public Health at Diné College.

    PubMed

    Garrison, Edward R

    2007-10-01

    Diné College was established by an Act of the US Congress in 1968 as the first Native American tribally-controlled college. It is chartered by the Navajo Nation and operates eight campuses to serve a reservation community spread over 25,000 square miles. In 2004, Diné College became the first tribal college to establish a degree program in Public Health, and, in accordance with the college's mission, considerable efforts have been made to incorporate Navajo language and cultural materials into the teaching curriculum of this degree program. Materials are presented here that have been developed not only by Diné College but also by the Department of Diné Education (of the Navajo tribal government) and by the Northern Navajo Medical Center (Indian Health Service). These materials describe some of the core philosophical concepts, both in Navajo and in English, some of the complex symbolism associated with these core concepts, and some of the applications to daily living that derive from these core concepts. The purpose for the use of these materials in the curriculum is to ensure that students, who are almost all Navajo, will be prepared for providing Public Health educational and intervention services that are well suited to the cultural environment of the Navajo People. PMID:17896247

  19. Apportioning riverine DIN load to export coefficients of land uses in an urbanized watershed.

    PubMed

    Shih, Yu-Ting; Lee, Tsung-Yu; Huang, Jr-Chuan; Kao, Shuh-Ji; Chang

    2016-08-01

    The apportionment of riverine dissolved inorganic nitrogen (DIN) load to individual land use on a watershed scale demands the support of accurate DIN load estimation and differentiation of point and non-point sources, but both of them are rarely quantitatively determined in small montane watersheds. We introduced the Danshui River watershed of Taiwan, a mountainous urbanized watershed, to determine the export coefficients via a reverse Monte Carlo approach from riverine DIN load. The results showed that the dynamics of N fluctuation determines the load estimation method and sampling frequency. On a monthly sampling frequency basis, the average load estimation of the methods (GM, FW, and LI) outperformed that of individual method. Export coefficient analysis showed that the forest DIN yield of 521.5kg-Nkm(-2)yr(-1) was ~2.7-fold higher than the global riverine DIN yield (mainly from temperate large rivers with various land use compositions). Such a high yield was attributable to high rainfall and atmospheric N deposition. The export coefficient of agriculture was disproportionately larger than forest suggesting that a small replacement of forest to agriculture could lead to considerable change of DIN load. The analysis of differentiation between point and non-point sources showed that the untreated wastewater (non-point source), accounting for ~93% of the total human-associated wastewater, resulted in a high export coefficient of urban. The inclusion of the treated and untreated wastewater completes the N budget of wastewater. The export coefficient approach serves well to assess the riverine DIN load and to improve the understanding of N cascade.

  20. Assessing sinkhole activity in the Ebro Valley mantled evaporite karst using advanced DInSAR

    NASA Astrophysics Data System (ADS)

    Galve, Jorge Pedro; Castañeda, Carmen; Gutiérrez, Francisco; Herrera, Gerardo

    2015-01-01

    Sinkholes in karst areas may cause subsidence damage in transportation infrastructures, demolition of buildings and even the loss of human lives when they occur in a catastrophic way. Differential Interferometry (DInSAR) is a promising technology for detecting and characterizing sinkholes, as well as for reducing the associated risk when combined with other sources of data such as a sinkhole inventory. In this work, the usefulness of InSAR techniques and data for sinkhole risk management has been analyzed through the comparison of three DInSAR-derived velocity maps with a comprehensive sinkhole inventory in the Ebro Valley, NE Spain. The DInSAR maps have contributed to improve the sinkhole inventory in different ways: (1) detection of non-inventoried sinkholes; (2) revision of sinkhole areas previously classified as inactive as active; and (3) refinement of underestimated sinkhole boundaries. The obtained results suggest that DInSAR products are suitable for analyzing active dissolution-induced subsidence. The application of these techniques may help in recognizing and better characterizing previously unknown karst subsidence problems and in preventing personal and property losses. However, the analysis reveals that the available DInSAR maps combined overlook about 70% of the previously mapped active sinkholes mainly due to decorrelation.

  1. Estudio dinámico de un potencial perturbador dependiente de dos parámetros

    NASA Astrophysics Data System (ADS)

    Miloni, O.; Brunini, A.

    El objeto del presente trabajo consiste en el estudio dinámico de un sistema dinámico caracterizado por la función hamiltoniana correspondiente a un satélite planetario perturbado por la acción del Sol y del achatamiento del planeta madre. Cuando dicha Hamiltoniana se promedia respecto de los términos de corto período, esta queda con dos grados de libertad, y su estudio puede ser realizado con las herramientas clásicas de la dinámica no-lineal. Se tratará de determinar regiones regulares y caóticas de movimiento. En el caso de estas últimas, es de particular interés la determinación de su orígen.

  2. The DinB Superfamily Includes Novel Mycothiol, Bacillithiol and Glutathione S-transferases

    PubMed Central

    Newton, Gerald L.; Leung, Stephan S.; Wakabayashi, Judy I.; Rawat, Mamta; Fahey, Robert C.

    2011-01-01

    The superfamily of glutathione S-transferases has been the subject of extensive study but Actinobacteria produce mycothiol (MSH) in place of glutathione and no mycothiol S-transferase (MST) has been identified. Using mycothiol and monochlorobimane as substrates a MST activity was detected in extracts of Mycobacterium smegmatis and purified sufficiently to allow identification of MSMEG_0887, a member the DUF664 family of the DinB superfamily, as the MST. The identity of the M. smegmatis and homologous Mycobacterium tuberculosis (Rv0443) enzymes was confirmed by cloning and the expressed proteins were found to be active with MSH but not bacillithiol (BSH) or glutathione (GSH). Bacillus subtilis YfiT is another member of the DinB superfamily but this bacterium produces BSH. The YfiT protein was shown to have S-transferase activity with monochlorobimane when assayed with BSH but not with MSH or GSH. Enterococcus faecalis EF_3021 shares some homology with MSMEG_0887 but this organism produces GSH but not MSH or BSH. Cloned and expressed EF_0321 was active with monochlorobimane and GSH but not with MSH or BSH. MDMPI_2 is another member of the DinB superfamily and has been previously shown to have mycothiol-dependent maleylpyruvate isomerase activity. Three of the eight families of the DinB superfamily include proteins shown to catalyze thiol-dependent metabolic or detoxification activities. Since more than two-thirds of the sequences assigned to the DinB superfamily are members of these families it seems likely that such activity is dominant in the DinB superfamily. PMID:22059487

  3. A novel cis-acting element required for DNA damage-inducible expression of yeast DIN7

    SciTech Connect

    Yoshitani, Ayako; Yoshida, Minoru; Ling Feng

    2008-01-04

    Din7 is a DNA damage-inducible mitochondrial nuclease that modulates the stability of mitochondrial DNA (mtDNA) in Saccharomyces cerevisiae. How DIN7 gene expression is regulated, however, has remained largely unclear. Using promoter sequence alignment, we found a highly conserved 19-bp sequence in the promoter regions of DIN7 and NTG1, which encodes an oxidative stress-inducible base-excision-repair enzyme. Deletion of the 19-bp sequence markedly reduced the hydroxyurea (HU)-enhanced DIN7 promoter activity. In addition, nuclear fractions prepared from HU-treated cells were used in in vitro band shift assays to reveal the presence of currently unidentified trans-acting factor(s) that preferentially bound to the 19-bp region. These results suggest that the 19-bp sequence is a novel cis-acting element that is required for the regulation of DIN7 expression in response to HU-induced DNA damage.

  4. Connection and Community: Diné College Emphasizes Real-World Experience in Public Health

    ERIC Educational Resources Information Center

    Bauer, Mark

    2016-01-01

    The Summer Research Enhancement Program (SREP) at Diné College provides students with a solid foundation of public health research methods and includes a hands-on internship in their home community to test their newly acquired skills while enhancing the communities' health. Focusing on health issues prioritized by Navajo health leaders, from…

  5. Initial Reliability of the Diagnostic Interview for Narcissism Adapted for Preadolescents: Parent Version (P-DIN)

    PubMed Central

    Guilé, Jean-Marc; Sayegh, Liliane; Bergeron, Line; Fortier, Hélène; Goldberg, Deborah; Gunderson, John

    2004-01-01

    Introduction the Diagnostic Interview for Narcissism, an instrument developed by Gunderson and associates to assess pathological narcissistic traits in adults, has been adapted for use with parents of preadolescents as a semi-structured interview. A sixth section has been added to assess the parental narcissistic investment of the child. Methods the sample consists of 21 parents of children (aged 8–13 years) at risk for narcissistic personality disorder. An interviewer-observer design, with independent interview evaluation, was used to assess inter-rater reliabilities. Both raters were blind to diagnostic information. Results Very good inter-rater reliabilities (ranging from .85 to 1.00) were obtained for all 35 statements of this Parent version of the DIN (P-DIN). Good internal consistencies a=0.82, a=0.88, a=0.69, respectively) were obtained for the first three Sections of the P-DIN, which include all the DSM-IV criteria for Narcissistic Personality Disorder. Section V, Social/Moral Adaptation (a=0.54), and Section VI, Parental Narcissistic Investment of the Child (a=0.62), had weaker internal consistencies. Section IV, Mood States, had the lowest internal consistency (a=0.50). Finally, a high reliability coefficient was obtained for the total scale (a=0.92, 32 statements for Sections I to V). Conclusion present results of this pilot study justify further research into the P-DIN psychometric properties. PMID:19030504

  6. Landslide risk assessment with multi pass DInSAR analysis and error suppressing approach

    NASA Astrophysics Data System (ADS)

    yun, H.; Kim, J.; Lin, S.; Choi, Y.

    2013-12-01

    Landslide is one of the most dreadful natural hazards and the prime risk source causing lethal damages in many countries. In spite of various attempts to measure the landslide susceptibility by the remote sensed method including Differential Interferometric SAR (DInSAR) analysis, the construction of reliable forecasting systems still remains unsolved. Thus, we tackled the problem of DInSAR analysis for monitoring landslide risk over the mountainous areas where InSAR observations are usually contaminated by the orographic effects and other error elements. In order to measure the correct surface deformation which might be a prelude of landslide, time series analysis and atmospheric correction of DInSAR interferograms were conducted and crossly validated. The target area of this experiment is the eastern part of Korean peninsula centered in Uljin. In there, the landslide originated by the geomorphic factors such as high sloped topography and localized torrential down pour is critical issue. The landslide cases frequently occurred in the cutting side of mountainous area by the anthropogenic construction activities. Although high precision DInSAR measurements for monitoring the landslide risks are essential in such circumstances, it is difficult to attain sufficient enough accuracy because of the external factors inducing the error component in electromagnetic wave propagation. For instance, the local climate characteristics such as orographic effect and the proximity to seashore can produce the significant anomalies in the water vapor distribution and consequently result in the error components of InSAR phase angle measurements. Moreover the high altitude parts of target area cause the stratified tropospheric delay error in DInSAR measurement. After all, the improved DInSAR approaches to cope all above obstacles are highly necessary. Thus we employed two approaches i.e. StaMPS/MTI (Stanford Method for Persistent Scatterers/Multi-Temporal InSAR, Hopper et al., 2007

  7. Assessment of DInSAR Potential in Simulating Geological Subsurface Structure

    NASA Astrophysics Data System (ADS)

    Fouladi Moghaddam, N.; Rudiger, C.; Samsonov, S. V.; Hall, M.; Walker, J. P.; Camporese, M.

    2013-12-01

    High resolution geophysical surveys, including seismic, gravity, magnetic, etc., provide valuable information about subsurface structuring but they are very costly and time consuming with non-unique and sometimes conflicting interpretations. Several recent studies have examined the application of DInSAR to estimate surface deformation, monitor possible fault reactivation and constrain reservoir dynamic behaviour in geothermal and groundwater fields. The main focus of these studies was to generate an elevation map, which represents the reservoir extraction induced deformation. This research study, however, will focus on developing methods to simulate subsurface structuring and identify hidden faults/hydraulic barriers using DInSAR surface observations, as an innovative and cost-effective reconnaissance exploration tool for planning of seismic acquisition surveys in geothermal and Carbon Capture and Sequestration regions. By direct integration of various DInSAR datasets with overlapping temporal and spatial coverage we produce multi-temporal ground deformation maps with high resolution and precision to evaluate the potential of a new multidimensional MSBAS technique (Samsonov & d'Oreye, 2012). The technique is based on the Small Baseline Subset Algorithm (SBAS) that is modified to account for variation in sensor parameters. It allows integration of data from sensors with different wave-band, azimuth and incidence angles, different spatial and temporal sampling and resolutions. These deformation maps then will be used as an input for inverse modelling to simulate strain history and shallow depth structure. To achieve the main objective of our research, i.e. developing a method for coupled InSAR and geophysical observations and better understanding of subsurface structuring, comparing DInSAR inverse modelling results with previously provided static structural model will result in iteratively modified DInSAR structural model for adequate match with in situ observations

  8. The management of ductal intraepithelial neoplasia (DIN): open controversies and guidelines of the Istituto Europeo di Oncologia (IEO), Milan, Italy.

    PubMed

    Farante, Gabriel; Zurrida, Stefano; Galimberti, Viviana; Veronesi, Paolo; Curigliano, Giuseppe; Luini, Alberto; Goldhirsch, Aron; Veronesi, Umberto

    2011-07-01

    The management of ductal intraepithelial neoplasia (DIN) has substantially changed over the past 30 years, as its incidence has increased (from 2-3% to more than 20%), mainly due to the widespread use of mammography screening. This article describes not only the more widespread theoretical concepts on DIN but also the differences in the practical applications of the theory between different countries, different oncology specialists, and different cancer centers. Papers related to the international multicentre-randomized trials and retrospective studies were analyzed. We include articles and papers published between 1993 and 2010 related to patients with DIN, and abstracts and reports from MEDLINE and other sources were indentified. The standard of care for DIN consists of (a) breast conservative surgery (mastectomy is still indicated in large lesions--masses or microcalcifications--in about 30% of cases); (b) radiotherapy (RT) after conservative surgery, and (c) medical treatment in estrogen receptors-positive patients. However, most studies have shown significant differences between theory and practical application. Moreover, there are differences regarding (a) the indications of sentinel lymph node biopsy, (b) the definition and identification of low-risk DIN subgroups that can avoid RT and tamoxifen, and (c) the research into new alternative drugs in adjuvant medical therapy. A general agreement on the best management of DIN does not exist as yet. New large trials are needed in order to define the best management of DIN patients which is (in most respects) still complex and controversial.

  9. DinB upregulation is the sole role of the SOS response in stress-induced mutagenesis in Escherichia coli.

    PubMed

    Galhardo, Rodrigo S; Do, Robert; Yamada, Masami; Friedberg, Errol C; Hastings, P J; Nohmi, Takehiko; Rosenberg, Susan M

    2009-05-01

    Stress-induced mutagenesis is a collection of mechanisms observed in bacterial, yeast, and human cells in which adverse conditions provoke mutagenesis, often under the control of stress responses. Control of mutagenesis by stress responses may accelerate evolution specifically when cells are maladapted to their environments, i.e., are stressed. It is therefore important to understand how stress responses increase mutagenesis. In the Escherichia coli Lac assay, stress-induced point mutagenesis requires induction of at least two stress responses: the RpoS-controlled general/starvation stress response and the SOS DNA-damage response, both of which upregulate DinB error-prone DNA polymerase, among other genes required for Lac mutagenesis. We show that upregulation of DinB is the only aspect of the SOS response needed for stress-induced mutagenesis. We constructed two dinB(o(c)) (operator-constitutive) mutants. Both produce SOS-induced levels of DinB constitutively. We find that both dinB(o(c)) alleles fully suppress the phenotype of constitutively SOS-"off" lexA(Ind(-)) mutant cells, restoring normal levels of stress-induced mutagenesis. Thus, dinB is the only SOS gene required at induced levels for stress-induced point mutagenesis. Furthermore, although spontaneous SOS induction has been observed to occur in only a small fraction of cells, upregulation of dinB by the dinB(o(c)) alleles in all cells does not promote a further increase in mutagenesis, implying that SOS induction of DinB, although necessary, is insufficient to differentiate cells into a hypermutable condition. PMID:19270270

  10. [Reform of the Law DIN EN ISO 9001:2000. Commentary on the new requirements on quality management systems].

    PubMed

    Eckert, H; Böhmer, K

    2000-09-01

    Since January this year the German translation of the third draft to the reform of the DIN EN ISO 9000 is available. The draft reveals an approximation to the models of Business Excellence. Most important changes are a far stronger customer orientation, orientation on the processes and resource management. The norms DIN EN ISO 9002 and 9003 have been removed, ISO 8402 has been integrated in the reformed DIN EN ISO 9000. Apart from that the compatibility with other management systems has been improved. It was the aim of the reform to improve the applicability for all types of business, products and services.

  11. Railway deformation detected by DInSAR over active sinkholes in the Ebro Valley evaporite karst, Spain

    NASA Astrophysics Data System (ADS)

    Galve, J. P.; Castañeda, C.; Gutiérrez, F.

    2015-11-01

    Subsidence was measured for the first time on railway tracks in the central sector of Ebro Valley (NE Spain) using Differential Synthetic Aperture Radar Interferometry (DInSAR) techniques. This area is affected by evaporite karst and the analysed railway corridors traverse active sinkholes that produce deformations in these infrastructures. One of the railway tracks affected by slight settlements is the Madrid-Barcelona high-speed line, a form of transport infrastructure highly vulnerable to ground deformation processes. Our analysis based on DInSAR measurements and geomorphological surveys indicates that this line shows dissolution-induced subsidence and compaction of anthropogenic deposits (infills and embankments). Significant sinkhole-related subsidence was also measured by DInSAR techniques on the Castejón-Zaragoza conventional railway line. This study demonstrates that DInSAR velocity maps, coupled with detailed geomorphological surveys, may help in the identification of the railway track sections that are affected by active subsidence.

  12. "We're still in a struggle": Diné resilience, survival, historical trauma, and healing.

    PubMed

    Goodkind, Jessica R; Hess, Julia Meredith; Gorman, Beverly; Parker, Danielle P

    2012-08-01

    As part of a community/university collaborative effort to promote the mental health and well-being of Diné (Navajo) youth, we explored the relevance of addressing historical trauma and current structural stressors, and of building on individual and community strengths through healing and social transformation at multiple levels. Qualitative analyses of 74 ethnographic interviews with 37 Diné youth, parents, and grandparents suggested that a focus on historical trauma as a conceptual frame for behavioral health inequities, understood within the context of resilience and survival, is appropriate. Our findings also highlight the salience of current stressors such as poverty and violence exposure. We explore the fit of an historical trauma healing framework and present implications for intervention and transformation through revitalization of traditional knowledge, culturally based healing practices, intergenerational education, and social change strategies designed to eliminate social inequities. PMID:22707344

  13. On the application of DInSAR to deformation monitoring in desert areas

    NASA Astrophysics Data System (ADS)

    Chang, Xiao-Tao; Guo, Jin-Yun; Zhang, Yong-Hong; Wang, Xiao-Qing

    2011-03-01

    The DInSAR technique is used for monitoring the desert height changes to study sandstorms. Hunshandake Sandy Land, as the test area, is one of the main sources of sandstorms in Beijing. In order to study the sandstorm source and its impact, a pair of EnviSat ASAR images of Oct. 11, 2005, and Oct. 26, 2004, is processed on the basis of analysis of six ERS-2 and EnviSat radar images. After the image configuration, flat earth effect correction, data filtering, phase unwrapping, and geo-coding, a deformation model over Hunshandake desert is built. According to the results, the height decreased in most areas and increased in a few areas, which basically coincides with the strong sandstorm appearing in Beijing in the Spring of 2005. The results show DInSAR has an important role in monitoring of desert surface deformation.

  14. Ground deformation of Tenerife volcano island revealed by 1992-2005 DInSAR time series:

    NASA Astrophysics Data System (ADS)

    Tizzani, P.

    2009-04-01

    We study the state of deformation of Tenerife Island using Differential Synthetic Aperture Radar Interferometry (DInSAR). We apply the Small BAseline Subset (SBAS) DInSAR algorithm to radar images acquired from 1992 to 2005 by ERS sensors to determine the deformation rate distribution and the time series for the coherent pixels identified in the island. Our analysis reveals that the summit area of the volcanic edifice is characterized by a continuous subsidence extending well beyond Las Cañadas caldera rim and corresponding to the intrusive core of the island. These results, coupled with GPS ones, structural and geological information and deformation modelling, suggest that the intrusive complex is subsiding into a weak lithosphere and that the volcanic edifice is in a state of compression. We also detect more localized deformation patterns correlated with water table changes and variations in the time deformation associated with the seismic crisis in 2004.

  15. Effects of different N sources on riverine DIN export and retention in a subtropical high-standing island, Taiwan

    PubMed Central

    Huang, Jr-Chuan; Lee, Tsung-Yu; Lin, Teng-Chiu; Hein, Thomas; Lee, Li-Chin; Shih, Yu-Ting; Kao, Shuh-Ji; Shiah, Fuh-Kwo; Lin, Neng-Huei

    2016-01-01

    Increases in nitrogen (N) availability and mobility resulting from anthropogenic activities have substantially altered the N cycle, both locally and globally. Taiwan characterized by the subtropical montane landscape with abundant rainfall, downwind of the most rapidly industrializing eastern coast of China, can be a demonstration site for extremely high N input and riverine DIN (dissolved inorganic N) export. We used 49 watersheds with similar climatic and landscape settings but classified into low, moderate, and highly disturbed categories based on population density to illustrate their differences in nitrogen inputs (through atmospheric N deposition, synthetic fertilizers, and human emission) and DIN export ratios. Our results showed that the island-wide average riverine DIN export is ~ 3800 kg N km−2 yr−1, approximately 18 times the global average. The average riverine DIN export ratios are 0.30−0.51, which are much higher than the averages of 0.20−0.25 of large rivers around the world, indicating excessive N input relative to ecosystem demand or retention capacity. The low disturbed watersheds have a high N retention capacity and DIN export ratios of 0.06−0.18 in spite of the high N input (~ 4900 kg N km−2 yr−1). The high retention capacity is likely due to effective uptake by secondary forests in the watersheds. The moderately disturbed watersheds show a linear increase in DIN export with increases in total N inputs and mean DIN export ratios of 0.20 to 0.31. The main difference in land use between low and moderately disturbed watersheds is the greater proportion of agricultural land cover in the moderately disturbed watersheds. Thus, their greater DIN export could be attributed to N fertilizers used in the agricultural lands. The greater export ratios also imply that agricultural lands have a lower proportional N retention capacity and that reforestation could be an effective land management practice to reduce riverine DIN export. The export

  16. Effects of different N sources on riverine DIN export and retention in a subtropical high-standing island, Taiwan

    NASA Astrophysics Data System (ADS)

    Huang-Chuan, Jr.; Lee, Tsung-Yu; Lin, Teng-Chiu; Hein, Thomas; Lee, Li-Chin; Shih, Yu-Ting; Kao, Shuh-Ji; Shiah, Fuh-Kwo; Lin, Neng-Huei

    2016-03-01

    Increases in nitrogen (N) availability and mobility resulting from anthropogenic activities have substantially altered the N cycle, both locally and globally. Taiwan characterized by the subtropical montane landscape with abundant rainfall, downwind of the most rapidly industrializing eastern coast of China, can be a demonstration site for extremely high N input and riverine DIN (dissolved inorganic N) export. We used 49 watersheds with similar climatic and landscape settings but classified into low, moderate, and highly disturbed categories based on population density to illustrate their differences in nitrogen inputs (through atmospheric N deposition, synthetic fertilizers, and human emission) and DIN export ratios. Our results showed that the island-wide average riverine DIN export is ˜ 3800 kg N km-2 yr-1, approximately 18 times the global average. The average riverine DIN export ratios are 0.30-0.51, which are much higher than the averages of 0.20-0.25 of large rivers around the world, indicating excessive N input relative to ecosystem demand or retention capacity. The low disturbed watersheds have a high N retention capacity and DIN export ratios of 0.06-0.18 in spite of the high N input (˜ 4900 kg N km-2 yr-1). The high retention capacity is likely due to effective uptake by secondary forests in the watersheds. The moderately disturbed watersheds show a linear increase in DIN export with increases in total N inputs and mean DIN export ratios of 0.20 to 0.31. The main difference in land use between low and moderately disturbed watersheds is the greater proportion of agricultural land cover in the moderately disturbed watersheds. Thus, their greater DIN export could be attributed to N fertilizers used in the agricultural lands. The greater export ratios also imply that agricultural lands have a lower proportional N retention capacity and that reforestation could be an effective land management practice to reduce riverine DIN export. The export ratios of the

  17. Enhancing DInSAR capabilities for landslide monitoring by applying GIS-based multicriteria filtering analysis

    NASA Astrophysics Data System (ADS)

    Beyene, F.; Knospe, S.; Busch, W.

    2015-04-01

    Landslide detection and monitoring remain difficult with conventional differential radar interferometry (DInSAR) because most pixels of radar interferograms around landslides are affected by different error sources. These are mainly related to the nature of high radar viewing angles and related spatial distortions (such as overlays and shadows), temporal decorrelations owing to vegetation cover, and speed and direction of target sliding masses. On the other hand, GIS can be used to integrate spatial datasets obtained from many sources (including radar and non-radar sources). In this paper, a GRID data model is proposed to integrate deformation data derived from DInSAR processing with other radar origin data (coherence, layover and shadow, slope and aspect, local incidence angle) and external datasets collected from field study of landslide sites and other sources (geology, geomorphology, hydrology). After coordinate transformation and merging of data, candidate landslide representing pixels of high quality radar signals were filtered out by applying a GIS based multicriteria filtering analysis (GIS-MCFA), which excludes grid points in areas of shadow and overlay, low coherence, non-detectable and non-landslide deformations, and other possible sources of errors from the DInSAR data processing. At the end, the results obtained from GIS-MCFA have been verified by using the external datasets (existing landslide sites collected from fieldworks, geological and geomorphologic maps, rainfall data etc.).

  18. New A-DInSAR study of La Palma, Canary Islands, Spain. Results and interpretation.

    NASA Astrophysics Data System (ADS)

    Escayo, Joaquín; Bru, Guadalupe; Camacho, Antonio; Prieto, Juan F.; Mallorquí, Jordi J.; Fernández, José

    2016-04-01

    We present new results on the deformation field for La Palma Island in the Canary Archipelago using the complete archive of Envisat (2004-2010). The recent volcanic activity registered in La Palma (at historical and subhistorical times, there have been seven eruptions, in ca. A.D. 1480, 1585, 1646, 1677, 1712, 1949 and 1971) and the absence of any geodetic monitoring system implemented in the Island at the 90's converts A-DInSAR studies in an basic information source for the study of surface displacements. From late 90's several geodetic studies using GNSS, gravimetry and InSAR techniques has been carried out in the island (see Fernández et al., 2015 for a summary). We improve previous radar satellite results by increasing the temporal coverage and using more images, which generates a greater interferogram set, and using a recently developed A-DInSAR processing technique which includes an error estimation for the LOS mean velocity and deformation time series ("Subsidence" software, developed by the "Universitat Politècnica de Catalunya, see e.g., Blanco-Sánchez et al., 2008, and Centolanza, 2015). Our A-DInSAR results are compared with previous InSAR ones and with GNSS results obtained from campaigns. A discussion and interpretation of the results is also presented. Radar images have been provided by ESA through Cat.-1 13933 project.

  19. Multiple signaling pathways in gene expression during sugar starvation. Pharmacological analysis of din gene expression in suspension-cultured cells of Arabidopsis.

    PubMed

    Fujiki, Y; Ito, M; Nishida, I; Watanabe, A

    2000-11-01

    We have identified many dark-inducible (din) genes that are expressed in Arabidopsis leaves kept in the dark. In the present study we addressed the question of how plant cells sense the depletion of sugars, and how sugar starvation triggers din gene expression in suspension-cultured cells of Arabidopsis. Depletion of sucrose in the medium triggered marked accumulation of din transcripts. Suppression of din gene expression by 2-deoxy-Glc, and a non-suppressive effect exerted by 3-O-methyl-Glc, suggested that sugar-repressible expression of din genes is mediated through the phosphorylation of hexose by hexokinase, as exemplified in the repression of photosynthetic genes by sugars. We have further shown that the signaling triggered by sugar starvation involves protein phosphorylation and dephosphorylation events, and have provided the first evidence that multiple pathways of protein dephosphorylation exist in sugar starvation-induced gene expression. An inhibitor of serine/threonine protein kinase, K-252a, inhibited din gene expression in sugar-depleted cells. Okadaic acid, which may preferentially inhibit type 2A protein phosphatases over type 1, enhanced the transcript levels of all din genes, except din6 and din10, under sugar starvation. Conversely, a more potent inhibitor of type 1 and 2A protein phosphatases, calyculin A, increased transcripts from din2 and din9, but decreased those from other din genes, in sugar-depleted cells. On the other hand, calyculin A, but not okadaic acid, completely inhibited the gene expression of chlorophyll a/b-binding protein under sugar starvation. These results indicate that multiple signaling pathways, mediated by different types of protein phosphatases, regulate gene expression during sugar starvation. PMID:11080291

  20. EPOSAR: an innovative service to provide EPOS community with advanced DInSAR products

    NASA Astrophysics Data System (ADS)

    Manunta, Michele; De Luca, Claudio; Elefante, Stefano; Lanari, Riccardo; Pepe, Antonio; Zinno, Ivana; Casu, Francesco

    2015-04-01

    The quantitative evaluation of ground deformation is traditionally based on in-situ surveying techniques that, through the intensive use of GPS stations, automatic total stations and levelling benchmarks, can measure up to sub-centimetre displacements. In the last decades, the extensive use of satellite remote sensing data, such as Synthetic Aperture Radar (SAR) images, has represented an important breakthrough in the context of non-invasive ground deformation analyses over large areas, thanks to their large spatial coverage and relatively short revisit time, as well as to their medium-high ground resolution. In such a context, the well-known Differential SAR Interferometry (DInSAR) technique allows us to map and measure deformation phenomena due to both natural and man-made causes with centimetre to millimetre accuracy. The Earth Science community has a wide interest in the use of DInSAR displacement maps both for crisis management and risk mitigation activities, and for surveillance, monitoring and analysis of geophysical phenomena. In areas characterized by high level of hazards the availability of routinely generated advanced DInSAR products would allow a fast analysis of their current status, providing a near real time monitoring. Similarly, an on-demand service would allow the customization of the products by selecting the area of interest, the SAR data to be processed, and other processing parameters to be set by the users to edit/correct/improve the final products. In this work we discuss the Satellite Data Thematic Core Service of EPOS and we present the EPOSAR service. In particular, the EPOSAR service, based on the well-known DInSAR approach referred to as Small Baseline Subset (SBAS), accomplishes a shared and synergic Earth Observation (EO) service aimed at designing, implementing and harmonizing efficient satellite data processing chains capable of ingesting the significantly increased data stream expected from the ESA Sentinel-1 satellites. EPOSAR

  1. Effects of different N sources on riverine DIN export and retention in subtropical high-standing island, Taiwan

    NASA Astrophysics Data System (ADS)

    Huang, J.-C.; Lee, T.-Y.; Lin, T.-C.; Hein, T.; Lee, L.-C.; Shih, Y.-T.; Kao, S.-J.; Shiah, F.-K.; Lin, N.-H.

    2015-10-01

    Increases in nitrogen (N) availability and mobility resulting from anthropogenic activities has substantially altered N cycle both locally and globally. Taiwan characterized by the subtropical montane landscape with abundant rainfall, downwind to the most rapidly industrializing east coast of China can be a demonstration site for extreme high N input and riverine DIN (dissolved inorganic N) export. We used 49 watersheds classified into low-, moderate-, and highly-disturbed categories based on population density to illustrate their differences in nitrogen inputs through atmospheric N deposition, synthetic fertilizers and human emission and DIN export ratios. Our results showed that the island-wide average riverine DIN export is ~ 3800 kg N km-2 yr-1, approximately 18-fold higher than the global average mostly due to the large input of synthetic fertilizers. The average riverine DIN export ratio is 0.30-0.51, which is much higher than the average of 0.20-0.25 of large rivers around the world indicating excessive N input relative to ecosystem demand or retention capacity. The low-disturbed watersheds, despite of high N input, only export 0.06-0.18 of the input so were well buffered to changes in input quantity suggesting high efficiency of nitrogen usage or high N retention capacity of the less disturbed watersheds. The high retention capacity probably is due to the effective uptake by secondary forests in the watersheds. The moderate-disturbed watersheds show a linear increase of output with increases in total N inputs and a mean DIN export ratio of 0.20 to 0.31. The main difference in land use between low and moderately disturbed watershed is the relative proportions of agricultural land and forests, not the built-up lands. Thus, their greater DIN export quantity could be attributed to N fertilizers used in the agricultural lands. The greater export ratios also imply that agricultural lands have lower proportional N retention capacity and that reforestation could be

  2. [Quality assurance in student training. Prerequisites for DIN EN ISO 9001:2000 in teaching].

    PubMed

    Ochsner, W; Kaiser, C; Schirmer, U

    2007-07-01

    Standards of quality assurance according to DIN EN ISO 9001:2000 have been implemented in many university hospital departments, but often teaching activities are not included. This work presents a method that allows, after having defined the various teaching activities as sub-processes of one single core process, to include the manifold teaching activities of university hospital departments into the certification process. The stepwise description of the prerequisites for including teaching activities into ISO 9001 certification is illustrated by a concrete implementation example.

  3. Evolución Dinámica de Cúmulos Estelares Abiertos

    NASA Astrophysics Data System (ADS)

    de La Fuente Marcos, R.

    Las estrellas que observamos no se formaron aisladamente, sino que lo hicieron en grupos o cúmulos. Estos sistemas estelares recibenel nombre de cúmulos estelares abiertos o galácticos cuando están constituidos por estrellas de la Población I. Los cúmulos abiertos se localizan preferentemente en el plano galáctico, y en muchos de ellos está teniendo lugar aún una activa formación estelar. El propósito principal de esta tesis doctoral es el estudio de la evolución dinámica de estos sistemas estelares por medio de simulaciones numéricas y de la comparación de sus resultados con datos observacionales. Con este fin se analizan los efectos que, sobre la dinámica de los cúmulos, ejercen varios fenómenos de interés astrofísico tales como el campo gravitatorio galáctico, la pérdida de masa causada por la evolución estelar y la presencia de binarias primordiales. En este trabajo se presentan los resultados de más de un centenar de modelos de cúmulos, con poblaciones comprendidas en el intervalo [100, 10.000] estrellas, calculados con NBODY5, un programa estándar en el campo de la Dinámica Estelar Experimental. De los mismos se deduce que el mecanismo principal que rige la dinámica de los cúmulos abiertos es la evolución estelar de su distribución de masas, encontrándose un comportamiento diferencial fuertemente dependiente de la población inicial del cúmulo. Los mecanismos responsables de la desintegración de los cúmulos abiertos son analizados en detalle, proponiéndose un modelo analítico que ajusta razonablemente los resultados de las simulaciones. Además, y con el fin de explicar el elevado número de sistemas múltiples observados en cúmulos abiertos, se estudian los efectos que, sobre los mismos, ejerce la presencia de una cierta fracción de binarias primordiales. El papel de las binarias tambiín depende de la riqueza del cúmulo y sus efectos se interrelacionan con aquellos debidos a la evolución estelar. Por último, se

  4. Diné (Navajo) parents' and community leaders' perceptions of agriculture-related injury risk to youth: a social narrative.

    PubMed

    Shumway, K; Pate, M L; McNeal, L G

    2014-01-01

    The purpose of this study was to provide a formative needs assessment of Diné (Navajo) parents for the prevention of childhood injuries resulting from livestock and horses. The research objectives were to identify parents' perceived livestock and horse related injury risks to Diné children and describe Diné community stakeholder input on prevention interventions for reducing injury risks to children associated with livestock and horse related activities on farms or ranches. The assessment used a survey constructed of closed and open-response questions to gauge Diné farmers' and ranchers' perceptions of injury risks to children who live or work on agricultural operations. Additional questions were asked to gauge Diné acceptance of an online training program as a prevention intervention to reduce livestock and horse related injuries to children. A total of 96 individuals agreed to participate in the survey and provided usable responses. A total of 53.2% (f = 50) of participants were female. Sixty-three percent of participants (f = 58) perceived that youth who work with intact male livestock were at high risk for injury. A total of 25 individuals perceived that youth who ride horses without equestrian helmets were at high risk for injury. Approximately 96% (f = 89) of those surveyed agreed or strongly agreed that they would use an online training program to promote agricultural health and safety for Diné youth. When participants were asked if there were safety issues associated with having youth working on a farm or ranch, a very large portion felt that the biggest issue was a lack of education and instruction from elders. A recommendation for an injury prevention practice included developing a user-friendly online network, giving parents and community leaders access to resources to assist in educating youth in local agricultural traditions integrated with safety training. PMID:24804462

  5. DIN retention-transport through four hydrologically connected zones in a headwater catchment of the Upper Mississippi River

    USGS Publications Warehouse

    Triska, F.J.; Duff, J.H.; Sheibley, R.W.; Jackman, A.P.; Avanzino, R.J.

    2007-01-01

    Dissolved inorganic nitrogen (DIN) retention-transport through a headwater catchment was synthesized from studies encompassing four distinct hydrologic zones of the Shingobee River Headwaters near the origin of the Mississippi River. The hydrologic zones included: (1) hillslope ground water (ridge to bankside riparian); (2) alluvial riparian ground water; (3) ground water discharged through subchannel sediments (hyporheic zone); and (4) channel surface water. During subsurface hillslope transport through Zone 1, DIN, primarily nitrate, decreased from ???3 mg-N/l to <0.1 mg-N/l. Ambient seasonal nitrate:chloride ratios in hillslope flow paths indicated both dilution and biotic processing caused nitrate loss. Biologically available organic carbon controlled biotic nitrate retention during hillslope transport. In the alluvial riparian zone (Zone 2) biologically available organic carbon controlled nitrate depletion although processing of both ambient and amended nitrate was faster during the summer than winter. In the hyporheic zone (Zone 3) and stream surface water (Zone 4) DIN retention was primarily controlled by temperature. Perfusion core studies using hyporheic sediment indicated sufficient organic carbon in bed sediments to retain ground water DIN via coupled nitrification-denitrification. Numerical simulations of seasonal hyporheic sediment nitrification-denitrification rates from perfusion cores adequately predicted surface water ammonium but not nitrate when compared to 5 years of monthly field data (1989-93). Mass balance studies in stream surface water indicated proportionally higher summer than winter N retention. Watershed DIN retention was effective during summer under the current land use of intermittently grazed pasture. However, more intensive land use such as row crop agriculture would decrease nitrate retention efficiency and increase loads to surface water. Understanding DIN retention capacity throughout the system, including special channel

  6. Insights into the dynamics of Mt Etna volcano from gravity and DInSar observations

    NASA Astrophysics Data System (ADS)

    Del Negro, C.; Sansosti, E.; Greco, F.; Pepe, A.; Currenti, G.; Solaro, G.; Napoli, R.; Pepe, S.; Pistorio, A.

    2012-04-01

    18-years (September 1994 - October 2011) gravity and ground deformation sequences, recorded at Etna volcano along an East-West trending profile of 19 stations on the southern flank at a quasi-monthly sampling rate, are presented. Over the last two decades, frequent fountaining events and several flank eruptions occurred at Mt Etna. We use the SBAS DInSAR technique to analyze the temporal evolution of surface displacements by inverting a sequence of interferograms to form a deformation time series. Height changes, evaluated by DInSAR data during the entire period, show modest vertical variations unable to produce significant gravity changes. However, the gravity data set was corrected for the small height variations using the experimental free-air gravity gradients measured at two stations of the profile. The residual space-time gravity image displayed some gravity increase/decrease cycles, mostly affecting the central and eastern stations of the East-West profile. We attributed these gravity cycles to mass redistribution processes mainly located at a depth of 2-4 km bsl in a region recognized to be a preferential pathway of magma rising and an intermediate zone of magma storage/withdrawal. In the latter period 2008-2011, when several paroxysmal events occurred from the South East crater, the gravity and height deformation patterns show many similarities with the previous period 1995-2000 encompassing a long series of paroxysmal episodes that preceded the violent and dramatic explosive/effusive eruptions of 2001 and 2002-2003.

  7. Expression and mutational analysis of DinB-like protein DR0053 in Deinococcus radiodurans.

    PubMed

    Appukuttan, Deepti; Seo, Ho Seong; Jeong, Sunwook; Im, Sunghun; Joe, Minho; Song, Dusup; Choi, Jungjoon; Lim, Sangyong

    2015-01-01

    In order to understand the mechanism governing radiation resistance in Deinococcus radiodurans, current efforts are aimed at identifying potential candidates from a large repertoire of unique Deinococcal genes and protein families. DR0053 belongs to the DinB/YfiT protein family, which is an over-represented protein family in D. radiodurans. We observed that dr0053 transcript levels were highly induced in response to gamma radiation (γ-radiation) and mitomycin C (MMC) exposure depending on PprI, RecA and the DrtR/S two-component signal transduction system. Protein profiles demonstrated that DR0053 is a highly induced protein in cultures exposed to 10 kGy γ-radiation. We were able to determine the transcriptional start site of dr0053, which was induced upon irradiation, and to assign the 133-bp promoter region of dr0053 as essential for radiation responsiveness through primer extension and promoter deletion analyses. A dr0053 mutant strain displayed sensitivity to γ-radiation and MMC exposure, but not hydrogen peroxide, suggesting that DR0053 helps cells recover from DNA damage. Bioinformatic analyses revealed that DR0053 is similar to the Bacillus subtilis protein YjoA, which is a substrate of bacterial protein-tyrosine kinases. Taken together, the DNA damage-inducible (din) gene dr0053 may be regulated at the transcriptional and post-translational levels.

  8. Monthly migration of a tectonic seismic swarm detected by DInSAR: southwest Peloponnese, Greece

    NASA Astrophysics Data System (ADS)

    Kyriakopoulos, Christodoulos; Chini, Marco; Bignami, Christian; Stramondo, Salvatore; Ganas, Athanassios; Kolligri, Maria; Moshou, Alexandra

    2013-09-01

    In the period 2011 June-October, a tectonic swarm of nearly 1222 earthquakes occurred in the Messenia prefecture at the southwestern region of the Peloponnese Peninsula. The swarm happened in the Messenia's Upper Quaternary basin, 25 km NW of the city of Kalamata, and migrated from NNW towards SSE. The largest earthquakes occurred in 2011 August 14 (Mw = 4.8), September 14 (Mw = 4.6) and October 10 (Mw = 4.7), caused moderate structural damages mainly in old houses in four villages and produced particular unrest to the local population. We have investigated the monthly migration of the swarm using Differential Synthetic Aperture Radar Interferometry (DInSAR), presenting for the first time a very close look at the deformation evolution that may reveal an aseismic slip component of the total movement. The geodetically derived slip distribution for the first 4 months revealed that slip migrated laterally along strike (north to south) and vertically from a deep portion, at ˜2.8 km depth, to a shallow portion, at less than 0.5 km, of the fault plane, and concluded its migration towards the surface with a very shallow Mw 4.7 event of 2011 October 10 surprisingly detected by DInSAR.

  9. Expression and Mutational Analysis of DinB-Like Protein DR0053 in Deinococcus radiodurans

    PubMed Central

    Appukuttan, Deepti; Seo, Ho Seong; Jeong, Sunwook; Im, Sunghun; Joe, Minho; Song, Dusup; Choi, Jungjoon; Lim, Sangyong

    2015-01-01

    In order to understand the mechanism governing radiation resistance in Deinococcus radiodurans, current efforts are aimed at identifying potential candidates from a large repertoire of unique Deinococcal genes and protein families. DR0053 belongs to the DinB/YfiT protein family, which is an over-represented protein family in D. radiodurans. We observed that dr0053 transcript levels were highly induced in response to gamma radiation (γ-radiation) and mitomycin C (MMC) exposure depending on PprI, RecA and the DrtR/S two-component signal transduction system. Protein profiles demonstrated that DR0053 is a highly induced protein in cultures exposed to 10 kGy γ-radiation. We were able to determine the transcriptional start site of dr0053, which was induced upon irradiation, and to assign the 133-bp promoter region of dr0053 as essential for radiation responsiveness through primer extension and promoter deletion analyses. A dr0053 mutant strain displayed sensitivity to γ-radiation and MMC exposure, but not hydrogen peroxide, suggesting that DR0053 helps cells recover from DNA damage. Bioinformatic analyses revealed that DR0053 is similar to the Bacillus subtilis protein YjoA, which is a substrate of bacterial protein-tyrosine kinases. Taken together, the DNA damage-inducible (din) gene dr0053 may be regulated at the transcriptional and post-translational levels. PMID:25706748

  10. Surface deformation analysis of the Istanbul (Turkey) city retrieved via the SBAS-DInSAR technique

    NASA Astrophysics Data System (ADS)

    Manzo, Mariarosaria; Lanari, Riccardo; Manconi, Andrea; Solaro, Giuseppe; Walter, Thomas R.; Zschau, Jochen

    2010-05-01

    Remote sensing techniques make possible to collect information on dangerous or inaccessible areas. In this context, space-based geodetic techniques as Differential SAR Interferometry (DInSAR) have been used in several areas in order to obtain co-seismic surface deformation maps in a few days or even hours following large earthquakes. The retrieved surface deformation can be used to constrain analytical and/or numerical models to derive parameters such as depth, dimension, orientation, and slip occurred on the fault plane. Moreover, advanced DInSAR techniques allow observing the temporal evolution of the surface displacements, and are thus able to furnish a picture of the pre-seismic state as well as of the post-seismic effects. In this work, we present DInSAR analyses of the deformation patterns in areas that are affected by seismic hazard. In particular, we focus on ground displacements occurred in the greater city area of Istanbul (Turkey) in the last 17 years. To this aim, we exploited the advanced DInSAR algorithm, referred to as Small BAseline Subset (SBAS) technique (Berardino et al., 2002). Displacement time series are retrieved from data acquired by the ERS-1/2 and ENVISAT (Pepe et al., 2005) satellites of the European Space Agency (ESA) between 1992 and 2009. First, we show the results of an analysis carried out at a spatial resolution of about 100 x 100 m. This shows, in addition to the co-seismic displacement caused by the Izmit earthquake (17 August 1999) and associated events, several areas that are subject to subsidence (often in excess of 10 cm per decade) within the city of Istanbul. Moreover, in selected case studies, we further exploited localized phenomena by "zooming" in the areas of interest and carrying out analyses at full spatial resolution scale (10 x 10 m) (Lanari et al., 2004). This additional effort allowed us to discriminate among deformation phenomena occurring at regional and at the building scale. This study provides an updated

  11. Sentinel-1 DInSAR processing chain within Geohazard Exploitation Platform

    NASA Astrophysics Data System (ADS)

    Zinno, Ivana; Bonano, Manuela; Buonanno, Sabatino; Casu, Francesco; De Luca, Claudio; Fusco, Adele; Lanari, Riccardo; Manunta, Michele; Manzo, Mariarosaria; Ojha, Chandrakanta; Pepe, Antonio

    2016-04-01

    The Sentinel-1A (S1A) satellite has been launched on April 2014 to acquire SAR data in continuity with the ERS-1/2 and ENVISAT missions. It presents advanced characteristics in terms of revisit time, spatial coverage and service reliability. Such a satellite will be paired during 2016 with the Sentinel-1B twin system that will reduce the constellation revisit time from 12 to 6 days. Accordingly, a huge and ever-increasing data flow relevant to extended areas on Earth will be delivered with a "free and open access" data policy. The S1-A sensor is equipped with a C-band SAR instrument that is conceived for interferometric applications, thus allowing us to analyze Earth's surface displacements through the Differential SAR Interferometry (DInSAR) technique. In particular, S1A SAR data are collected through the Terrain Observation by Progressive Scans (TOPS) mode, which generates Interferometric Wide Swath (IWS) acquisitions. To properly handle S1A TOPS data, the existing DInSAR processing chains have to be adapted with new procedures, which properly take into account the characteristics of this new acquisition mode. Furthermore, another critical point to be taken into account in designing a S1A DInSAR processing chain is the achievement of a good computational efficiency. Indeed, the capability to process in reduced time frames the huge data stream expected by S1A (and, very soon, also by S1B) is a key aspect to fully exploit S1 data archives. In this work we present an efficient interferometric processing chain, based on the advanced DInSAR algorithm referred to as Parallel Small BAseline Subset (P-SBAS), for the generation of S1A IWS surface deformation time-series. It ingests the Single Look Complex data and generates, in unsupervised way, interferograms and displacement time-series. This processing chain is able to exploit distributed computing architectures taking advantage of both multi-node and multi-threading programming techniques. The proposed S1A P

  12. Railway deformation detected by DInSAR over active sinkholes in the Ebro Valley evaporite karst, Spain

    NASA Astrophysics Data System (ADS)

    Galve, J. P.; Castañeda, C.; Gutiérrez, F.

    2015-06-01

    Previously not measured subsidence on railway tracks was detected using DInSAR displacement maps produced for the central sector of Ebro Valley (NE Spain). This area is affected by evaporite karst and the analyzed railway corridors traverse active sinkholes that produce deformations in these infrastructures. One of the railway tracks affected by slight settlements corresponds to the Madrid-Barcelona high-speed line, a transport infrastructure highly vulnerable to ground deformation processes. Our analysis based on DInSAR measurements and geomorphological surveys indicate that this line show dissolution-induced subsidence and compaction of anthropogenic deposits (infills and embankments). By using DInSAR techniques, it was also measured the significant subsidence related to the activity of sinkholes in the Castejón-Zaragoza conventional railway line. Thus, this study demonstrate that DInSAR velocity maps coupled with detailed geomorphological surveys may help in the identification of the sectors of railway tracks that may compromise the safety of travellers.

  13. Dinámica global en galaxias elípticas

    NASA Astrophysics Data System (ADS)

    Pérez, M. J.; Cincotta, P. M.; Giordano, C. M.

    Con el propósito de determinar propiedades dinámicas globales en sistemas triaxiales no integrables, utilizamos una nueva herramienta conocida como ``Mean Exponential Growth factor of Nearby Orbits'' (MEGNO), introducida por Cincotta y Simó (2000). Esta técnica no sólo resulta eficiente para investigar ambas componentes del espacio fase, regular y caótica, sino que también, provee una medida de la hiperbolicidad en el dominio caótico que coincide con la dada por el Lyapunov Characteristic Number (LCN). Previamente este método ha sido aplicado al estudio de modelos simples, y últimamente en el campo de la Mecánica Celeste, al estudio de sistemas planetarios extrasolares. En esta presentación, ilustraremos algunas de las propiedades más importantes del MEGNO, aplic& acute;andolo al potencial tridimensional de Stäckel perturbado.

  14. Unsupervised SBAS-DInSAR time series generation: a small brick for building a Supersites ecosystem

    NASA Astrophysics Data System (ADS)

    Casu, F.; De Luca, C.; Elefante, S.; Imperatore, P.; Lanari, R.; Manunta, M.; Zinno, I.; Farres, J.; Lengert, W.

    2013-12-01

    Differential SAR Interferometry (DInSAR) is an effective tool to detect and monitor ground displacements with centimeter accuracy. The geoscience communities, as well as those related to hazard monitoring and risk mitigation, make extensively use of DInSAR. They take advantage from the current huge amount of SAR data and will benefit the incoming big data stream of Sentinel 1 system. The availability of this information makes possible the generation of Earth's surface displacement maps and time series with large spatial coverage and long time span and, often in conjunction to in-situ data, fosters advances in science. However, the managing, processing and analysis of such a huge amount of data is expected to be the major bottleneck, particularly when crisis phases occur. The emerging need of creating a common ecosystem in which data (space born and in-situ), results and processing tools are shared, is envisaged to be a successful way to address such a problem and contribute to information and knowledge spreading. The Supersites initiative as well as the ESA SuperSites Exploitation Platform (SSEP), through the ESA Grid Processing On Demand (G-POD) and Cloud Computing Operational Pilot (CIOP) projects, provide effective answers to this need. The existent tools for querying and analysing SAR data are required to be redesigned for both processing big data and for quickly replying to simultaneous user requests, mainly during emergency situations. These requirements push for the development of automatic and unsupervised processing tools as well as of scalable, widely accessible and high performance computing capabilities. The cloud-computing environment successfully responds to these objectives, particularly in case of spike and peak requests of processing resources linked to disaster events. In this work we present a parallel computational model for the Small BAseline Subset (SBAS) DInSAR algorithm as it was implemented within the computing environment provided by the

  15. Unsupervised DInSAR processing chain for multi-scale displacement analysis

    NASA Astrophysics Data System (ADS)

    Casu, Francesco; Manunta, Michele

    2016-04-01

    Earth Observation techniques can be very helpful for the estimation of several sources of ground deformation due to their characteristics of large spatial coverage, high resolution and cost effectiveness. In this scenario, Differential Synthetic Aperture Radar Interferometry (DInSAR) is one of the most effective methodologies for its capability to generate spatially dense deformation maps at both global and local spatial scale, with centimeter to millimeter accuracy. DInSAR exploits the phase difference (interferogram) between SAR image pairs relevant to acquisitions gathered at different times, but with the same illumination geometry and from sufficiently close flight tracks, whose separation is typically referred to as baseline. Among several, the SBAS algorithm is one of the most used DInSAR approaches and it is aimed at generating displacement time series at a multi-scale level by exploiting a set of small baseline interferograms. SBAS, and generally DInSAR, has taken benefit from the large availability of spaceborne SAR data collected along years by several satellite systems, with particular regard to the European ERS and ENVISAT sensors, which have acquired SAR images worldwide during approximately 20 years. Moreover, since 2014 the new generation of Copernicus Sentinel satellites has started to acquire data with a short revisit time (12 days) and a global coverage policy, thus flooding the scientific EO community with an unprecedent amount of data. To efficiently manage such amount of data, proper processing facilities (as those coming from the emerging Cloud Computing technologies) have to be used, as well as novel algorithms aimed at their efficient exploitation have to be developed. In this work we present a set of results achieved by exploiting a recently proposed implementation of the SBAS algorithm, namely Parallel-SBAS (P-SBAS), which allows us to effectively process, in an unsupervised way and in a limited time frame, a huge number of SAR images

  16. Analysis of DSGSD using the DInSAR technique and geomorphological studies in central Italy

    NASA Astrophysics Data System (ADS)

    Tolomei, C.; Taramelli, A.; Moro, M.; Saroli, M.; Salvi, S.

    2008-12-01

    Considerable enhancement for morphometric interpretation can be obtained through generation of a synthetic stereo pair, by means of the integration of detailed photogeological analysis (Volo Italia 1987-1988) dataset, supported by SPOT images, 20m pixel-size Digital Elevation Model (DEM) and in situ observations. In this research we analyze the overall requirement and use of parameters derived from geomorphic analysis in synergy with DInSAR technique for Deep Seated Gravitational Slope Deformation (DSGSD) topography characterization in the Italy Central Apennine (Umbria-Marche area). The topographic approach employed to derive these insights is not intended for use in site-specific analyses of DSGSD potential but instead identify slopes whose morphology is indicative of deep seated phenomena. Geomorphological evidences from aerial photos and field observations shows large scale gravity driven phenomena (landslides, sackung or rock-flow, lateral spread and block slide), responsible for the landscape evolution of the whole area. The InSAR technique has been applied in order to understand the temporal behaviour and spatial distribution of such deformation. The interferograms show various isolated fringe patterns corresponding to some of the large scale gravitative phenomena previously and indipendently identified through geomorphic analysis. The final results indicate that when incorporated with the DInSAR technique the morphological analysis is useful to supervise the activity of identified DSGSDs in specific landscapes and quantify their surface movement. This research has promoted a structured and integrated approach to DSGSD assessment primarily from a quantitative perspective. The approach can have further positive implications. The application of the suggested methodology to areas characterized by the presence of different DSGSD typology and related to a seismic sequence could also allow to better separate tectonic and gravity contributions from the whole

  17. Dinámica y crecimiento de los granos de polvo en la nebulosa protoplanetaria

    NASA Astrophysics Data System (ADS)

    de La Fuente Marcos, Carlos

    2001-06-01

    En el escenario estándar de la formación planetaria, los planetesimales (cuerpos de tamaño kilométrico) crecen a partir de granos de polvo, similares a los interestelares, embebidos en un disco gaseoso denominado nebulosa protoplanetaria. Durante esta etapa, los movimientos del gas pueden tener gran influencia en la dinámica y el crecimiento de los granos de polvo, dado que el flujo kepleriano del gas frena el movimiento de los mismos haciendo que caigan hacia el Sol, y la turbulencia inhibe la inestabilidad gravitacional de la capa de polvo. Aunque se acepta que los planetesimales fueron los elementos constituyentes de los planetas, todavía se desconoce cómo se produjo la formación de los mismos. Por esta razón, en los estudios más recientes, existe un renovado interés por comprender mejor la evolución de la capa de polvo inmersa en el disco gaseoso de la Nebulosa. El gas que fluye en el disco puede engendrar estructuras carentes de simetría axial, como por ejemplo ondas espirales y vórtices, a partir de gran variedad de mecanismos de excitación e inestabilidad. En 1995, Barge y Sommeria pusieron de manifiesto que la existencia de vórtices gaseosos persistentes en la nebulosa solar tendría importantes consecuencias sobre la formación de los planetesimales y el posterior crecimiento de los planetas gigantes. La investigación desarrollada en esta Tesis analiza la relación entre el polvo y el gas debida al acoplamiento por fricción dinámica entre ambos; en concreto, se estudia el efecto del flujo medio del gas sobre la dinámica de las partículas de polvo. El primer objetivo es investigar en profundidad los procesos de captura y crecimiento de los granos de polvo dentro de un vórtice y su posible relevancia en cuanto a la formación de los planetesimales. El segundo objetivo es la exploración de los efectos de ondas espirales propagándose en el disco gaseoso sobre la dinámica y el crecimiento de las partículas. La presencia de líneas de

  18. A User-Oriented Methodology for DInSAR Time Series Analysis and Interpretation: Landslides and Subsidence Case Studies

    NASA Astrophysics Data System (ADS)

    Notti, Davide; Calò, Fabiana; Cigna, Francesca; Manunta, Michele; Herrera, Gerardo; Berti, Matteo; Meisina, Claudia; Tapete, Deodato; Zucca, Francesco

    2015-11-01

    Recent advances in multi-temporal Differential Synthetic Aperture Radar (SAR) Interferometry (DInSAR) have greatly improved our capability to monitor geological processes. Ground motion studies using DInSAR require both the availability of good quality input data and rigorous approaches to exploit the retrieved Time Series (TS) at their full potential. In this work we present a methodology for DInSAR TS analysis, with particular focus on landslides and subsidence phenomena. The proposed methodology consists of three main steps: (1) pre-processing, i.e., assessment of a SAR Dataset Quality Index (SDQI) (2) post-processing, i.e., application of empirical/stochastic methods to improve the TS quality, and (3) trend analysis, i.e., comparative implementation of methodologies for automatic TS analysis. Tests were carried out on TS datasets retrieved from processing of SAR imagery acquired by different radar sensors (i.e., ERS-1/2 SAR, RADARSAT-1, ENVISAT ASAR, ALOS PALSAR, TerraSAR-X, COSMO-SkyMed) using advanced DInSAR techniques (i.e., SqueeSAR™, PSInSAR™, SPN and SBAS). The obtained values of SDQI are discussed against the technical parameters of each data stack (e.g., radar band, number of SAR scenes, temporal coverage, revisiting time), the retrieved coverage of the DInSAR results, and the constraints related to the characterization of the investigated geological processes. Empirical and stochastic approaches were used to demonstrate how the quality of the TS can be improved after the SAR processing, and examples are discussed to mitigate phase unwrapping errors, and remove regional trends, noise and anomalies. Performance assessment of recently developed methods of trend analysis (i.e., PS-Time, Deviation Index and velocity TS) was conducted on two selected study areas in Northern Italy affected by land subsidence and landslides. Results show that the automatic detection of motion trends enhances the interpretation of DInSAR data, since it provides an objective

  19. Spatial and temporal interpolation of DInSAR data at different scales

    NASA Astrophysics Data System (ADS)

    Tessitore, Serena; Fiaschi, Simone; Achilli, Vladimiro; Ahmed, Ahmed; Calcaterra, Domenico; Di Martire, Diego; Guardiola-Albert, Carolina; Meisina, Claudia; Ramondini, Massimo; Floris, Mario

    2015-04-01

    The present study regards the utilization of multi-pass DInSAR algorithms to the ground displacements monitoring at small and large scales. An integration of in situ and DInSAR data to the elaboration of 2D maps of deformation is proposed. A geo-statistical method for "radar-gauge combination" called Ordinary Kriging of Radar Errors (OKRE) has been used. This algorithm uses the punctual values of a primary variable that is represented by measurements of true deformations, whereas radar is comprised as auxiliary information on the spatial distribution (Erdin, 2013). According to this method, is possible to obtain the interpolated map of deformations by subtracting a radar error map from the original interpolated radar map. In particular, the radar error map is carried out by interpolating the differences between radar and in situ data with the OK interpolator. To this aim, in the present work the available standard spirit levelling and GPS data have been used. Moreover, DInSAR data achieved through two different approaches have been taken into account for the spatial analysis and the error map computation at different scales. Specifically, the Persistent Scatterer Technique (PS-InSAR) and the Small BAseline Subset approach (SBAS) have been used to process the ENVISAT SAR images acquired in the period 2002-2010. In the SBAS processing chain, it is possible to activate the Disconnected Blocks tool and perform the SAR data "temporal interpolation". Since the estimation of the results in the processing takes into account the coherence threshold on the input images stack and their connection criteria, only the pixels above the threshold that are fully connected in all the images are solved. By activating the Disconnect Blocks tool, the results are estimated also for those pixels that respect the threshold criteria at least in the 60% of the images even in a not fully connected stack. In this way, the spatial coverage is higher but the reliability of the results is has to

  20. Advanced DInSAR analysis at Campi Flegrei and Vesuvius, Italy

    NASA Astrophysics Data System (ADS)

    Tiampo, K. F.; Camacho, A. G.; Fernandez, J.; Gonzalez, P. J.; Samsonov, S. V.

    2015-12-01

    Geodetic data, the spatial and temporal surface expression of complex geophysical processes in the earth, is being acquired today at unprecedented rates and accuracies. Differential interferometric synthetic aperture radar (DInSAR) is a satellite remote sensing technique used extensively today for mapping ground deformation with high spatial resolution and sub-centimeter precision over large areas that is particularly useful for volcanic monitoring [Massonnet and Feigl, 1998; Rosen et al., 2000]. Here we apply the advanced Multidimensional Small Baseline Subset (MSBAS) InSAR algorithm [Samsonov and d'Oreye, 2012] to several thousand Envisat and RADARSAT-2 images from 1993-2013 and compute time series of ground deformation over the Naples Bay region of Italy. Vesuvius and Campi Flegrei are located in this area in close proximity to the densely populated city of Naples and, as a result, it is one of the most hazardous volcanic areas in the world. We obtain time series of ground deformation at high spatial and temporal resolution that span, for the first time, twenty years. Campi Flegrei underwent continuous subsidence through 1999. Uplift began in 2005, reaching approximately 13 cm by 2013. We model the observed deformation to determine source parameters for subsidence and uplift epochs [Samsonov et al., 2014]. In addition, a typical DInSAR image can contain significant signals from with several different, nonvolcanic sources. For example, we clearly observe decade-long elevation-dependent seasonal oscillations of the vertical displacement component at Vesuvius that are substantially larger than the long-term deformation rate (<0.6 cm/yr). As a result, we employ an eigenpattern decomposition technique known as Karhunen-Loeve expansion (KLE) analysis in order to identify the unique, finite set of correlated deformation patterns associated with volcanic sources at different depths [Tiampo et al., 2004; Tiampo et al., 2012]. Both the inflation and deflation mechanisms

  1. Detrital control on the release of dissolved organic nitrogen (DON) and dissolved inorganic nitrogen (DIN) from the forest floor under chronic N deposition.

    PubMed

    Park, Ji-Hyung; Matzner, Egbert

    2006-09-01

    The role of detrital quantity and quality in forest floor N leaching was investigated in a litter manipulation experiment at a deciduous forest under chronic N deposition. Dissolved inorganic nitrogen (DIN) comprised the bulk of nitrogen leaching from the control except a short period following autumn litterfall. The dominance of DIN was strengthened by litter exclusion, whereas the addition of glucose or fresh litter led to a small increase in dissolved organic nitrogen (DON) and either a temporary or gradual reduction in NO(3)(-) release, respectively. Changes in soluble organic C and microbial C in the forest floor implied that increased availability of C sources might have enhanced microbial immobilization of DIN, either temporarily following glucose application or over the longer term following litter addition. The results suggest that detrital quantity and quality can play a crucial role in determining the balance between DIN and DON in N-enriched forest soils.

  2. A general framework and related procedures for multiscale analyses of DInSAR data in subsiding urban areas

    NASA Astrophysics Data System (ADS)

    Peduto, Dario; Cascini, Leonardo; Arena, Livia; Ferlisi, Settimio; Fornaro, Gianfranco; Reale, Diego

    2015-07-01

    In the last decade Differential Synthetic Aperture Radar (DInSAR) data were successfully tested in a number of case studies for the detection, mapping and monitoring of ground displacements associated with natural or anthropogenic phenomena. More recently, several national and regional projects all around the world provided rich data archives whose confident use, however, should rely on multidisciplinary experts in order to avoid misleading interpretations. To this aim, the present work first introduces a general framework for the use of DInSAR data; then, focusing on the analysis of subsidence phenomena and the related consequences to the exposed facilities, a set of original procedures is proposed. By drawing a multiscale approach the study highlights the different goals to be pursued at different scales of analysis via high/very high resolution SAR sensors and presents the results with reference to the case study of the Campania region (southern Italy) where widespread ground displacements occurred and damages of different severity were recorded.

  3. “We’re Still in a Struggle”: Diné Resilience, Survival, Historical Trauma, and Healing

    PubMed Central

    Goodkind, Jessica R.; Hess, Julia Meredith; Gorman, Beverly; Parker, Danielle P.

    2014-01-01

    As part of a community/university collaborative effort to promote the mental health and well-being of Diné (Navajo) youth, we explored the relevance of addressing historical trauma and current structural stressors and of building on individual and community strengths through healing and social transformation at multiple levels. Qualitative analyses of 74 ethnographic interviews with 37 Diné youth, parents, and grandparents suggested that a focus on historical trauma as a conceptual frame for behavioral health inequities, understood within the context of resilience and survival, is appropriate. Our findings also highlight the salience of current stressors such as poverty and violence exposure. We explore the fit of a historical trauma healing framework and present implications for intervention and transformation through revitalization of traditional knowledge, culturally-based healing practices, intergenerational education, and social change strategies designed to eliminate social inequities. PMID:22707344

  4. Comportamiento dinámico de asteroides en la región 23 < a < 26 UA

    NASA Astrophysics Data System (ADS)

    López García, F.

    Los Kuiper Belt Objects (KBOs) pueden ser una fuente de origen de los cometas de corto período. Muchos de los KBOs observados parecen provenir, al igual que el sistema Pluton-Charonte, de órbitas resonantes con Neptuno. Los Centauros son objetos que dinámicamente provienen de órbitas inestables cuyo semieje mayor se encuentra entre las órbitas de Júpiter y Neptuno. Pudiera ser que estos cuerpos fueron expulsados desde la región del cinturón de Kuiper y se encuentran en un proceso de ``scattering" debido a los efectos gravitacionales de los planetas gigantes. Su tiempo de vida dinámico es de algunos millones de años. La evolución orbital de los objetos trans-Neptunianos nos permite conocer su comportamiento anterior, por eso, es importante su relación dinámica con la evolución orbital de Neptuno. El objeto de este trabajo es estudiar el comportamiento dinámico de partículas test que se encuentran entre las resonancias 3:2 con Neptuno y 2:3 con Urano, las cuales comprenden una región de 2 UA aproximadamente. Los primeros resultados indican que la mayoría de los objetos ficticios son eyectados hacia la parte externa del Sistema Solar, mientras que sólo una parte pequeña del total de objetos estudiados, aproximadamente un 7%, son eyectados hacia la parte interna del Sistema Solar, y en algunos casos sus órbitas pueden cruzar la órbita de los planetas terrestres.

  5. Living in health, harmony, and beauty: the diné (navajo) hózhó wellness philosophy.

    PubMed

    Kahn-John Diné, Michelle; Koithan, Mary

    2015-05-01

    Hózhó is the complex wellness philosophy and belief system of the Diné (Navajo) people, comprised of principles that guide one's thoughts, actions, behaviors, and speech. The alignment of integrative nursing principles and the Hózhó Wellness Philosophy illustrates the power that integrative nursing offers as a meta-theoretical perspective that can transform our healthcare system so that it is inclusive and responsive to the needs of our varied populations. Integrative nursing offers the opportunity to re-introduce cultural wellness wisdom, such as Hózhó, as a means to improve whole-person/whole-systems wellbeing and resilience. Integrative nursing, through the acceptance and validation of indigenous health-sustaining wisdom, contributes to the delivery of effective, authentic, culturally tailored, whole-person/whole-system, patient-centered, relationship-based healthcare. Highlighting the Diné Hózhó philosophy re-introduces this philosophy to the Diné, other American Indian/Alaska Native nations, global indigenous cultures, and even nonindigenous people of the world as a means to promote and sustain global health and wellbeing.

  6. Living in Health, Harmony, and Beauty: The Diné (Navajo) Hózhó Wellness Philosophy

    PubMed Central

    Koithan, Mary

    2015-01-01

    Hózhó is the complex wellness philosophy and belief system of the Diné (Navajo) people, comprised of principles that guide one's thoughts, actions, behaviors, and speech. The alignment of integrative nursing principles and the Hózhó Wellness Philosophy illustrates the power that integrative nursing offers as a meta-theoretical perspective that can transform our healthcare system so that it is inclusive and responsive to the needs of our varied populations. Integrative nursing offers the opportunity to re-introduce cultural wellness wisdom, such as Hózhó, as a means to improve whole-person/whole-systems wellbeing and resilience. Integrative nursing, through the acceptance and validation of indigenous health-sustaining wisdom, contributes to the delivery of effective, authentic, culturally tailored, whole-person/whole-system, patient-centered, relationship-based healthcare. Highlighting the Diné Hózhó philosophy re-introduces this philosophy to the Diné, other American Indian/Alaska Native nations, global indigenous cultures, and even nonindigenous people of the world as a means to promote and sustain global health and wellbeing. PMID:25984415

  7. Phosphate mine subsidences deduced from differential interferometry (DInSAR): The Moulares case example (southern Atlas of Tunisia)

    NASA Astrophysics Data System (ADS)

    Ben Hassen, Mehdi; Rebai, Noamen; Deffontaines, Benoit; Turki, Mohamed Moncef; Chaabani, Fredj

    2011-11-01

    Tunisia is submitted to numerous small topographic displacements due to both the geodynamic of the Eurasian-African plates' convergence, and to important anthropic actions such as oil production, underground water pumping, mine extraction and linked post-mining displacements. We propose herein to study the latter and locate, characterize, and quantify small topographic displacement fields due to the production of underground phosphate mines in central Tunisia. After having acquired and processed 17 radar images (ERS 1 and 2) of the central Tunisia (Gafsa area) through Differential Interferometry (DInSAR), we clearly observed local subsidence that we interprete as corresponding to mine exploitation of the underground Moulares Phosphates mines (southern Atlas of Tunisia). Field studies (circular normal faults located above the Phosphate extraction area) confirm the movement revealed by DinSAR. Also, DInSAR allows us to monitor temporal variations of the small vertical displacements on this specific area and since the collapse occurred near an urban area (Moulares city), this problem can be considered a potential anthropic risk.

  8. [Certification of an RIA laboratory according to DIN EN ISO 9001-2000].

    PubMed

    Moser, E; Markowetz, D; Schächtele, S

    2002-06-01

    The university hospital Freiburg intends to establish step by step a total quality management system (TQMS) in all facilities with an external certification as its final aim. This has been reached already in the central laboratory. Therefore, it is effective for the department of nuclear medicine to do the same for its own lab specialized in thyroid hormones. The TQMS has been built up within six months on the basis of DIN EN ISO 9001:2000. This internationally accepted standard is of uttermost economical importance for an institution situated near the French and Swiss border. This review describes the procedure in detail. Responsible for the effort were the engagement of the coworkers in the lab as well as an adequate choice of the external adviser and the authority for certification. The procedure is formalized to a high degree and much understanding for analytic thinking and systematization is needed. Now it remains to be seen, if the desired effect (increased understanding for quality within the department, more efficient performance of the lab, better acceptance by the clients) will arise.

  9. El nuevo panorama de la Dinámica Galáctica

    NASA Astrophysics Data System (ADS)

    Pivovaroff, Michael James

    En general, la tendencia imperante en Dinámica Galáctica ha sido considerar que los movimientos estelares son básicamente regulares y que el caos no tiene mayor relevancia en los sistemas estelares. Sin embargo, en el último lustro se vienen acumulando pruebas de la importancia del movimiento caótico en ciertos sistemas estelares que existen en la naturaleza. Por una parte, sobre todo el grupo de David Merritt, lo ha mostrado en los casos de galaxias elípticas con concentraciones centrales de materia; por otra parte, en nuestro propio grupo, lo hemos mostrado para el caso de los satélites galácticos. Las consecuencias de estos hallazgos son tanto de tipo técnico, por la necesidad de construir modelos que contengan órbitas caóticas, como astrofísico, por los efectos del caos sobre la estacionariedad y evolución de los sistemas estelares en los que se presenta.

  10. [Oswald Bumke in Leipzig. Beyond Kraepelin, Freud and Rüdin's Entartungslehre].

    PubMed

    Steinberg, H

    2008-03-01

    Oswald Bumke is a central figure in twentieth-century German psychiatry, having had a considerable influence on its development as one of its best-known representatives. His time in Leipzig from 1921 to 1924 and subsequently in Munich up to the mid-1930s saw the second major phase in his scientific work, during which he laid the basis for the renown he still enjoys as a result of his specialist encyclopaedic textbooks and manuals summarising the current knowledge of his time. At the beginning of the 1920s he made his stand on the burning issues of the day and thus influenced the conceptional history of the subject. For instance, he proposed his own philosophical psychology, rejecting the experimental psychological approach of Emil Kraepelin. By challenging the libido theory and the dynamic unconscious he weakened the impact of Sigmund Freud and psychoanalysis on German scientific psychiatry. Moreover, Bumke strongly opposed the prevailing concept of degeneration and its main protagonist Ernst Rüdin. Owing to the political and social developments at the time, however, he was not able to raise much support among his colleagues.

  11. Fully exploitation of SBAS-DInSAR deformation time series for assessing structural damage: the case study of Rome, Italy

    NASA Astrophysics Data System (ADS)

    Bonano, Manuela; Arangio, Stefania; Calò, Fabiana; Di Mauro, Maria; Marsella, Maria; Manunta, Michele

    2014-05-01

    Remote sensing techniques have demonstrated to be effective tools to support natural and man-made risk mitigation activities. Among these, the Differential Synthetic Aperture Radar (SAR) Interferometry (DInSAR) technology is largely exploited in geoscience, oil and gas extraction, and landslide fields. Recently, thanks to the large availability of high resolution SAR systems (10 m or less), as well as to the development of advanced data processing techniques, DInSAR products have also started to be effectively used for applications in urban areas to detect localized displacements affecting single buildings and infrastructures. The advanced DInSAR technique referred to as Small Baseline Subset (SBAS) (Lanari et al., 2004) allows us to generate very long deformation time series, by exploiting large SAR datasets spanning up to 20 years (Bonano et al., 2012). Thanks to its capability to investigate wide areas, the SBAS-DInSAR technique is particularly suitable to remotely analyse the structural conditions of buildings located in densely urbanized zones. In this work, we fully exploit the results achieved over the city of Rome, Italy, through the well-established SBAS-DInSAR approach, aimed at performing a quantitative assessment of structural damage in urban areas affected by ground deformation (Arangio et al., 2013). More in details, we present an innovative methodology that integrates the SBAS-DInSAR measurements within an existing model, in order to assess the damage, and possibly estimate the future structural conditions, of single buildings affected by significant foundation settlements. In particular, a semi-empirical approach, based on a laminated beam model (Finno et al., 2005), is applied to investigate the damage of buildings located in the southern part of the city. The obtained results are in substantial agreement with in situ surveys, proving that the presented approach is an effective tool for the preliminary evaluation of the structural conditions in

  12. Two Host-Induced Ralstonia solanacearum Genes, acrA and dinF, Encode Multidrug Efflux Pumps and Contribute to Bacterial Wilt Virulence▿ †

    PubMed Central

    Brown, Darby G.; Swanson, Jill K.; Allen, Caitilyn

    2007-01-01

    Multidrug efflux pumps (MDRs) are hypothesized to protect pathogenic bacteria from toxic host defense compounds. We created mutations in the Ralstonia solanacearum acrA and dinF genes, which encode putative MDRs in the broad-host-range plant pathogen. Both mutations reduced the ability of R. solanacearum to grow in the presence of various toxic compounds, including antibiotics, phytoalexins, and detergents. Both acrAB and dinF mutants were significantly less virulent on the tomato plant than the wild-type strain. Complementation restored near-wild-type levels of virulence to both mutants. Addition of either dinF or acrAB to Escherichia coli MDR mutants KAM3 and KAM32 restored the resistance of these strains to several toxins, demonstrating that the R. solanacearum genes can function heterologously to complement known MDR mutations. Toxic and DNA-damaging compounds induced expression of acrA and dinF, as did growth in both susceptible and resistant tomato plants. Carbon limitation also increased expression of acrA and dinF, while the stress-related sigma factor RpoS was required at a high cell density (>107 CFU/ml) to obtain wild-type levels of acrA expression both in minimal medium and in planta. The type III secretion system regulator HrpB negatively regulated dinF expression in culture at high cell densities. Together, these results show that acrAB and dinF encode MDRs in R. solanacearum and that they contribute to the overall aggressiveness of this phytopathogen, probably by protecting the bacterium from the toxic effects of host antimicrobial compounds. PMID:17337552

  13. DInSAR time series generation within a cloud computing environment: from ERS to Sentinel-1 scenario

    NASA Astrophysics Data System (ADS)

    Casu, Francesco; Elefante, Stefano; Imperatore, Pasquale; Lanari, Riccardo; Manunta, Michele; Zinno, Ivana; Mathot, Emmanuel; Brito, Fabrice; Farres, Jordi; Lengert, Wolfgang

    2013-04-01

    One of the techniques that will strongly benefit from the advent of the Sentinel-1 system is Differential SAR Interferometry (DInSAR), which has successfully demonstrated to be an effective tool to detect and monitor ground displacements with centimetre accuracy. The geoscience communities (volcanology, seismicity, …), as well as those related to hazard monitoring and risk mitigation, make extensively use of the DInSAR technique and they will take advantage from the huge amount of SAR data acquired by Sentinel-1. Indeed, such an information will successfully permit the generation of Earth's surface displacement maps and time series both over large areas and long time span. However, the issue of managing, processing and analysing the large Sentinel data stream is envisaged by the scientific community to be a major bottleneck, particularly during crisis phases. The emerging need of creating a common ecosystem in which data, results and processing tools are shared, is envisaged to be a successful way to address such a problem and to contribute to the information and knowledge spreading. The Supersites initiative as well as the ESA SuperSites Exploitation Platform (SSEP) and the ESA Cloud Computing Operational Pilot (CIOP) projects provide effective answers to this need and they are pushing towards the development of such an ecosystem. It is clear that all the current and existent tools for querying, processing and analysing SAR data are required to be not only updated for managing the large data stream of Sentinel-1 satellite, but also reorganized for quickly replying to the simultaneous and highly demanding user requests, mainly during emergency situations. This translates into the automatic and unsupervised processing of large amount of data as well as the availability of scalable, widely accessible and high performance computing capabilities. The cloud computing environment permits to achieve all of these objectives, particularly in case of spike and peak

  14. Quality management in a radiological practice: experiences with a certification for DIN EN ISO 9001:2000.

    PubMed

    Kirsch, Michael; Vogg, Ingrid; Hosten, Norbert; Flessa, Steffen

    2010-07-01

    This paper describes the introduction of a total quality management system in a radiological practice. Certification was based on DIN EN ISO 9001:2000. The implementation of the quality management system had to overcome a number of barriers, for instance, legal obligations of a partnership association, leadership problems, and the fear to loose all hindered implementation. The knowledge of these barriers induces a faster and cheaper implementation of a quality management system in a radiological practice as a foundation of improved quality and competitiveness.

  15. Fatigue life assessment of 316L stainless steel and DIN-1.4914 martensitic steel before and after TEXTOR exposure

    NASA Astrophysics Data System (ADS)

    Shakib, J. I.; Ullmaier, H.; Little, E. A.; Schmitz, W.; Faulkner, R. G.; Chung, T. E.

    1992-09-01

    The effects of plasma exposure in the TEXTOR tokomak on elevated temperature fatigue lifetime and failure micromechanisms of 316L austenitic stainless steel and DIN 1.4914 martensitic steel (NET reference heats) have been evaluated. Fatigue tests were carried out in vacuum in the temperature range 150°-450°C and compared with data from reference specimens.Plasma-induced surface modifications lead to significant deterioration in fatigue life of 316L steel, whereas the lifetime of 1.4914 steel is unaffected. Fatigue in the 1.4914 steel is surface-initiated only at high stresses. At low stress amplitudes internal fatigue initiation at inclusions was observed.

  16. How operational Advanced-DInSAR Analysis can improve knowledge on natural and anthropogenic deformations for Nuclear Power Plant areas

    NASA Astrophysics Data System (ADS)

    Vollrath, Andreas; Zucca, Francesco; Stramondo, Salvatore; Bignami, Christian; Roeder, Johannes

    2015-04-01

    The application of Advanced Differential Interferometric Synthetic Aperture Radar (A-DINSAR) techniques has strongly emerged in the last two decades and became an important part in georelated fields. State-of-the-art A-DInSAR methods, such as Persistent Scatterer Interferometry (PSI) or the Small BASeline (SBAS) approach have demonstrated their usefulness in monitoring urban areas and single buildings, up to critical infrastructures. Combined with additional data from GPS networks or levelling, it could prove its large potential for an operational, cost-effective mapping of surface deformations. Given a reasonable amount of images, changes in surface deformation can be detected down to 1 mm/y. Compared to point-wise field measurements it offers a spatially consistent mapping approach from local to regional scales. In this review we want to provide a synopsis how A-DInSAR can be utilized in the framework of Nuclear Power Plant safety. Indeed, A-DInSAR is able to provide a detailed spatial analysis of slow movements occurring at NPP structures directly, as well as within the surrounding areas of the NPPs. Different phenomena of surface motion can be subject of such a monitoring. Natural causes, like active tectonics and terrain instability of slope which lead to landslides, as well as human-induced subsidence phenomena due to heavy construction or water pumping can be detected. We start by presenting techniques to determine the feasibility of the analysis for a given area and show its limitations. Then we propose a short insight into state-of-the-art studies where landslides, interseismic and human-induced deformation of the surface were mapped by A-DInSAR, to point out the relevance of a consequent analysis over an area of a NPP. Furthermore we present results of case studies from international projects (TERRAFIRMA) as well as preliminary results from the Krsko NPP in Slovenia. Finally, we provide a outlook into present and future trends concerning the use of freely

  17. Quality management in a radiological practice: experiences with a certification for DIN EN ISO 9001:2000.

    PubMed

    Kirsch, Michael; Vogg, Ingrid; Hosten, Norbert; Flessa, Steffen

    2010-07-01

    This paper describes the introduction of a total quality management system in a radiological practice. Certification was based on DIN EN ISO 9001:2000. The implementation of the quality management system had to overcome a number of barriers, for instance, legal obligations of a partnership association, leadership problems, and the fear to loose all hindered implementation. The knowledge of these barriers induces a faster and cheaper implementation of a quality management system in a radiological practice as a foundation of improved quality and competitiveness. PMID:19447575

  18. Exploitation of high-density DInSAR data points of the Umbria-Marche (Italy) 1997 seismic sequence for fault characteristics

    NASA Astrophysics Data System (ADS)

    Dalla Via, G.; Crippa, B.; Toraldo Serra, E. M.; Giacomuzzi, G.; Sabadini, R.

    2007-09-01

    High spatial resolution DInSAR data for the Umbria Marche 1997 seismic sequence are exploited by relaxing constraints derived from datasets of different nature, such as seismologically derived fault dimensions. DInSAR data are thus inverted for a realistic slip distribution over the faults, in terms of depth distribution and roughness, which allows us to relocate the main faults and to minimize the misfit between the vertical displacement pattern derived from DInSAR and model predictions. Our analysis reveals that slip affected not only the shallowest part of the fault system but also its deepest part, rupturing the whole seismogenic layer of the crust down to 10 km, reaching slip values up to 30 cm at the base of the seismogenic layer. Misfit is reduced by a factor of two with respect to previous analyses based on a smaller number of digitized fringe points.

  19. Ground deformation monitoring using small baseline DInSAR technique: A case study in Taiyuan City from 2003 to 2009

    USGS Publications Warehouse

    Wu, H.-A.; Zhang, Y.-H.; Chen, X.-Y.; Lu, T.; Du, J.; Sun, Z.-H.; Sun, G.-T.

    2011-01-01

    DInSAR technique based on time series of SAR images has been very popular to monitor ground stow deformation in recent years such as permanent scatterers (PS) method small baseline subsets (SBAS) method and coherent targets (CT) method. By taking advantage of PS method and CT method in this paper small baseline DTnSAR technique is used to investigate the ground deformation of Taiyuan City Shanxi Province from 2003 to 2009 by using 23 ENVISAT ASAR images. The experiment results demonstrate that: (1) during this period four significant subsidence centers have been developed in Taiyuan namely Xiayuan Wujiabu Xiaodian Sunjiazhai. The largest subsidence center is Sunjiazhai with an average subsidence rate of -77. 28 mm/a; (2) The subsidence of the old center Wanbolin has sHowed down. And the subsidence in the northern region has stopped and some areas even rebounded. (3) The change of subsidence centers indicates that the control measures of "closing wells and reducing exploitation" taken by the Taiyuan government has achieved initial effects. (4) The experiment results have been validated with leveling data and the acouracy is 2. 90 mm which shows that the small baseline DInSAR technique can be used to monitor urban ground deformation.

  20. Spatial-temporal surface deformation of Los Angeles over 2003-2007 from weighted least squares DInSAR

    NASA Astrophysics Data System (ADS)

    Hu, Jun; Li, Zhiwei; Ding, Xiaoli; Zhu, Jianjun; Sun, Qian

    2013-04-01

    The spatial-temporal evolution of surface displacement of Los Angeles area over 2003-2007 is measured with weighted least squares (WLS) small baseline (SB) DInSAR technique. 32 small baseline interferograms are generated from 18 SAR images acquired by the ENVISAT satellite and separated into two independent subsets. An additional interferogram with a longer baseline but good interferometric quality is used to link the two subsets. A time series of displacements with their corresponding standard deviations (STD) are derived from the WLS DInSAR solution by considering the interferometric displacement variances when determining the weighting scheme. Both the long-term trends and the seasonal variations of the displacements in the area are determined in the study and validated with GPS measurements from a number of stations of the Southern California Integrated GPS Network (SCIGN). The mean line-of-sight (LOS) displacement velocity map shows up to 3 cm/year of ground motion and up to 10 cm of accumulated displacements in Santa Fe Springs and -8 cm in Pomona over 2003-2007. Seasonal variations are identified in Santa Ana basin, the San Gabriel valley and the Lytle Creek basin, respectively.

  1. Ernst Rüdin's Unpublished 1922-1925 Study "Inheritance of Manic-Depressive Insanity": Genetic Research Findings Subordinated to Eugenic Ideology.

    PubMed

    Kösters, Gundula; Steinberg, Holger; Kirkby, Kenneth Clifford; Himmerich, Hubertus

    2015-11-01

    In the early 20th century, there were few therapeutic options for mental illness and asylum numbers were rising. This pessimistic outlook favoured the rise of the eugenics movement. Heredity was assumed to be the principal cause of mental illness. Politicians, scientists and clinicians in North America and Europe called for compulsory sterilisation of the mentally ill. Psychiatric genetic research aimed to prove a Mendelian mode of inheritance as a scientific justification for these measures. Ernst Rüdin's seminal 1916 epidemiological study on inheritance of dementia praecox featured large, systematically ascertained samples and statistical analyses. Rüdin's 1922-1925 study on the inheritance of "manic-depressive insanity" was completed in manuscript form, but never published. It failed to prove a pattern of Mendelian inheritance, counter to the tenets of eugenics of which Rüdin was a prominent proponent. It appears he withheld the study from publication, unable to reconcile this contradiction, thus subordinating his carefully derived scientific findings to his ideological preoccupations. Instead, Rüdin continued to promote prevention of assumed hereditary mental illnesses by prohibition of marriage or sterilisation and was influential in the introduction by the National Socialist regime of the 1933 "Law for the Prevention of Hereditarily Diseased Offspring" (Gesetz zur Verhütung erbkranken Nachwuchses).

  2. Characterization of dinY, a new Escherichia coli DNA repair gene whose products are damage inducible even in a lexA(Def) background.

    PubMed Central

    Petit, C; Cayrol, C; Lesca, C; Kaiser, P; Thompson, C; Defais, M

    1993-01-01

    Bacteriophage Mu dX(Ap lac) was used to isolate a mutation in an Escherichia coli lexA(Def) strain representing a previously undescribed gene (dinY) which does not seem to be under the direct control of LexA. The insertion created a dinY::lacZ fusion in which beta-galactosidase expression required a DNA-damaging treatment (UV irradiation or mitomycin) and activable RecA protein. This strain showed a decreased Weigle reactivation of bacteriophage lambda. However, it was fully inducible for UV mutagenesis. Two-dimensional gel electrophoresis analysis identified two spots absent in the mutant which were both UV inducible only in the presence of activated RecA protein (RecA*). This finding suggests that the dinY::lacZ fusion lies in a gene either that is under the direct control of activated RecA or whose product undergoes RecA*-dependent posttranscriptional/posttranslational modification(s). The dinY gene may also control the expression of some other gene(s) and/or lie in an operon. The fusion was mapped at a position between 41 and 41.5 min on the E. coli chromosome, in the vicinity of the ruv operon. Images PMID:8423139

  3. The Comparative Study of Morals and Democracy and Their Effect on the Behavioral Reflections of Khawaja Nasir Al-Din Tusi and John Dewey

    ERIC Educational Resources Information Center

    Mirzaei, Khalil; Golestani, Sayyed Hashem; Vaezi, Sayyed Hossain

    2016-01-01

    This study was aimed at comparatively analyzing morals and democracy from John Dewey and Khawaja Nasir al-Din Tusi's viewpoint. It also sought the effect of the two philosophers' viewpoint about morals and democracy and behavioral reflections. The purpose of this study was also to become familiar with the effect of morals and democracy on…

  4. Ernst Rüdin's Unpublished 1922-1925 Study "Inheritance of Manic-Depressive Insanity": Genetic Research Findings Subordinated to Eugenic Ideology.

    PubMed

    Kösters, Gundula; Steinberg, Holger; Kirkby, Kenneth Clifford; Himmerich, Hubertus

    2015-11-01

    In the early 20th century, there were few therapeutic options for mental illness and asylum numbers were rising. This pessimistic outlook favoured the rise of the eugenics movement. Heredity was assumed to be the principal cause of mental illness. Politicians, scientists and clinicians in North America and Europe called for compulsory sterilisation of the mentally ill. Psychiatric genetic research aimed to prove a Mendelian mode of inheritance as a scientific justification for these measures. Ernst Rüdin's seminal 1916 epidemiological study on inheritance of dementia praecox featured large, systematically ascertained samples and statistical analyses. Rüdin's 1922-1925 study on the inheritance of "manic-depressive insanity" was completed in manuscript form, but never published. It failed to prove a pattern of Mendelian inheritance, counter to the tenets of eugenics of which Rüdin was a prominent proponent. It appears he withheld the study from publication, unable to reconcile this contradiction, thus subordinating his carefully derived scientific findings to his ideological preoccupations. Instead, Rüdin continued to promote prevention of assumed hereditary mental illnesses by prohibition of marriage or sterilisation and was influential in the introduction by the National Socialist regime of the 1933 "Law for the Prevention of Hereditarily Diseased Offspring" (Gesetz zur Verhütung erbkranken Nachwuchses). PMID:26544949

  5. Reduction of deuterium permeation through DIN 1.4914 stainless steel (MANET) by plasma-spray deposited aluminium

    NASA Astrophysics Data System (ADS)

    Perujo, A.; Forcey, K. S.; Sample, T.

    1993-12-01

    The paper describes the formation of a permeation barrier on DIN 1.4914 (MANET) martensitic stainless steel by plasma spraying aluminium on the surface of the steel, followed by heat treatment of the sample to form Al 3Fe and Al 5Fe 2. Vacuum plasma spraying was chosen because it ensures that the sample will be exposed to low temperatures during the Al layer deposition and will not interfere with the heat treatment that MANET has to undergo in order to produce a homogeneous, fully martensitic structure. Measurements of the permeation rate of deuterium in the bare and aluminium-deposited MANET were performed by a gas permeation technique over the temperature range 573-743 K and for driving deuterium pressures in the range 3-50 kPa. Such measurements showed a reduction of the permeation rate between two and three orders of magnitude and there was evidence that surface reactions were the rate governing process.

  6. The Parallel SBAS-DInSAR algorithm: an effective and scalable tool for Earth's surface displacement retrieval

    NASA Astrophysics Data System (ADS)

    Zinno, Ivana; De Luca, Claudio; Elefante, Stefano; Imperatore, Pasquale; Manunta, Michele; Casu, Francesco

    2014-05-01

    Differential Synthetic Aperture Radar Interferometry (DInSAR) is an effective technique to estimate and monitor ground displacements with centimetre accuracy [1]. In the last decade, advanced DInSAR algorithms, such as the Small Baseline Subset (SBAS) [2] one that is aimed at following the temporal evolution of the ground deformation, showed to be significantly useful remote sensing tools for the geoscience communities as well as for those related to hazard monitoring and risk mitigation. DInSAR scenario is currently characterized by the large and steady increasing availability of huge SAR data archives that have a broad range of diversified features according to the characteristics of the employed sensor. Indeed, besides the old generation sensors, that include ERS, ENVISAT and RADARSAT systems, the new X-band generation constellations, such as COSMO-SkyMed and TerraSAR-X, have permitted an overall study of ground deformations with an unprecedented detail thanks to their improved spatial resolution and reduced revisit time. Furthermore, the incoming ESA Sentinel-1 SAR satellite is characterized by a global coverage acquisition strategy and 12-day revisit time and, therefore, will further contribute to improve deformation analyses and monitoring capabilities. However, in this context, the capability to process such huge SAR data archives is strongly limited by the existing DInSAR algorithms, which are not specifically designed to exploit modern high performance computational infrastructures (e.g. cluster, grid and cloud computing platforms). The goal of this paper is to present a Parallel version of the SBAS algorithm (P-SBAS) which is based on a dual-level parallelization approach and embraces combined parallel strategies [3], [4]. A detailed description of the P-SBAS algorithm will be provided together with a scalability analysis focused on studying its performances. In particular, a P-SBAS scalability analysis with respect to the number of exploited CPUs has

  7. Statistical elaborations of PS DInSAR data applied to the analysis of the subsidence affecting the Venetian coast

    NASA Astrophysics Data System (ADS)

    Tessitore, Serena; Fiaschi, Simone; Achilli, Vladimiro; Fabris, Massimo; Floris, Mario

    2015-04-01

    Subsidence is a hazard that may have natural or anthropic origin. It can affect wide areas causing important economic losses. The area of the Venetian coast is affected by subsidence mainly due to the exploitation of its resources (gas and water). In particular, about 40% of the Italian extraction activities are on this area and here the subsidence arise in conjunction with the industrial revolution (1950-1970). An effective monitoring system is necessary for the correct management of the resources exploitation that, very often, is not supervised. To this aim, the innovative DInSAR techniques have been effectively employed as monitoring systems for the risk assessments of various instability phenomena, such as subsidence, landslides, volcanic eruptions, earthquakes, sinkholes. These techniques represent a powerful investigation tool for their high spatial and multi-temporal coverage, fast data acquisition, and overall low costs. Their results are the displacement estimates along the satellite Line of Sight (LOS), the velocity map and the displacements time series for the whole observation period. In the present work, the ERS and ENVISAT DInSAR data, achieved through the Persistent Scatterers (PS) technique, have been used to produce the iso-kinetic maps of deformation for an area of about 4300 Km2. Here, the mean velocities computed along the ERS and ENVISAT observation periods 1992-2000 and 2003-2010 have been interpolated through the Ordinary Kriging (OK) method. Simulated values and estimations of subsidence uncertainties have been analysed to advance the current understanding on the phenomenon that affects the study area. The achieved maps give information about the spatial distribution of the rates of deformation, which could be correlated with the available geological, hydrogeological and geotechnical data, as well as with the recorded damage to the structures and infrastructures. Then, local Authorities can use these maps as useful tools for the monitoring

  8. Investigation of subsidence in the Manfredonia Gulf (Southern Italy) through multitemporal DInSAR techniques

    NASA Astrophysics Data System (ADS)

    Triggiani, M.; Refice, A.; Capolongo, D.; Bovenga, F.; Caldara, M.

    2009-04-01

    tourist sea village "Ippocampo". Here, unpublished studies based on ground data indicate average subsidence rates of the order of 0.20 mm/y in the last 125 ka for the inland area next to the village. More recently, height maps issued by the Italian Military Geographic Institute (IGM) in the 1950s report heights a.s.l. of the order of a few m. Observing that today the area is practically at sea level, an average subsidence of the order of tens of mm/y can be inferred for the last 50 years. To gain insight into the recent evolution of these phenomena, we investigate vertical movements on the coastal Tavoliere area through multitemporal differential Interferometric synthetic aperture radar (DInSAR) techniques. We use a persistent scatterers interferometry (PSI) processing methodology [2] to estimate subsidence displacement rates from long temporal series of SAR acquisitions. PSI techniques, first developed at POLIMI [3], allow to retrieve phase information from stacks of co-registered SAR interferograms spanning many years and taken from different directions with large baselines, by restricting the analysis to selected image pixels containing single objects with strong radar backscatter returns. Exploiting the high temporal stability of radar returns from these targets, it is possible to correct the images from spurious phase contributions such as atmospheric phase artefacts and errors in the digital elevation models used to account for topographic InSAR phase. Such stable objects typically coincide with man-made features, so successful applications of PSI techniques are mainly reported over urban centers. We processed a total of 105 SAR images acquired from the ERS-1/2 and ENVISAT satellites, organized in 3 stacks related to both descending (50 ERS-1/2 scenes) and ascending (25 ERS-1/2 and 30 ENVISAT scenes) acquisition geometries. The acquisitions refer to the temporal periods from 1995 to 2000 (ERS) and 2003 to 2008 (ENVISAT), respectively, with a temporal repetition

  9. Using DInSAR as a tool to detect unstable terrain areas in an Andes region in Ecuador (South America)

    NASA Astrophysics Data System (ADS)

    Mayorga Torres, Tannia

    2014-05-01

    Using DInSAR as a tool to detect unstable terrain areas in an Andes region in Ecuador (South America) 1. INTRODUCTION Monitoring landslides is a mandatory task in charge on the National Institute of Geological Research (INIGEMM) in Ecuador. It is a small country, supposedly will be faster doing monitoring, but what about its geographic characteristics? Lamentably, due to human and financial resources is not possible to put monitoring systems in unstable terrain areas. However, getting ALOS data to accessible price and using open source software to produce interferograms, could be a first step to know steep areas covered by vegetation and where mass movements are not visible. Under this statement, this study is part of the final research in a master study developed at CONAE during 2009-2011, with oral defense in August 2013. As a new technique used in Ecuador, the study processed radar data from ERS-1/2 and ALOS sensor PALSAR for getting differential interferograms, using ROI_PAC software. Stacking DInSAR is applied to get an average of displacement that indicates uplift and subsidence in the whole radar scene that covers two provinces in the Andes region. 2. PROBLEM Mass movements are present in the whole territory, independently of their magnitude and dynamic (slow or fast), they are a latent threat in winter season specially. There are registers of monitoring, such as two GPS's campaigns and artisanal extensometers, which are used to contrast with DInSAR results. However, the campaigns are shorter and extensometers are no trust on all. 3. METHODOLOGY Methodology has four phases of development: (1) Pre-processing of RAW data; (2) Processing of RAW data in ROI_PAC; (3) Post-processing for getting interferograms in units of cm per year; (4) Analysis of the results and comparison with ground truth. Sandwell & Price (1998) proposed Stacking technique to increase the fringes and decrease errors due to the atmosphere, to average several interferograms. L band penetrates

  10. Ground deformation of the western rift of Corinth observed by means of PSI, SBAS and DInSAR methodologies

    NASA Astrophysics Data System (ADS)

    Elias, Panagiotis; Briole, Pierre

    2013-04-01

    The rift of Corinth has been long identified as a site of major importance in Europe due to its intense tectonic activity. It is one of the world's most rapidly extending continental regions and it has one of the highest seismicity rates in the Euro-Mediterranean region. It produces in average, an earthquake of magnitude 6 per century. The GPS studies conducted since 1990 indicate a north-south extension rate across the rift of ~1.5 cm year-1 around its western termination. Geological evidences show that the south coast of the rift is uplifting whereas the north part is subsiding. The western termination of the rift in the Patras broader area presents a major scientific and socio-economic importance, with the Psathopyrgos and the Rion-Patras faults being located very close to the city of Patras. The first DInSAR studies were carried out using SAR/ERS data after the Ms= 6.2 June 15, 1995 Aigion earthquake and contributed to its characterization. More recently the ground deformation of the area has been measured using a series of ASAR/ENVISAT, PALSAR/ALOS and RASARSAT-2 acquisitions. All datasets were processed by means of PSI (Persistent Scatterers Interferometry), SBAS (Small Baseline SubSet) and DInSAR (Differential Interferometry with SAR) methodologies. In addition to widely used tools (DIAPASON, ROI-PAC, STAMPS e.t.c.) in-house procedures and tools have been developed in order to exploit of the synergy of multiple characteristics/properties (frequency, viewing angles, sides, etc) of the SAR acquisitions aiming to the minimisation of the noise components. We verified the agreement between GPS and PSI/SBAS velocities at the location of the five permanent GPS stations operated in the rift since ten years. Ground deformations are visible at various scales and at various places in the produced PSI/SBAS maps and several known faults exhibit ground deformation around them with no earthquake occurred during the observations period: (a) On 18th and 22nd of January 2010

  11. Developmental and Cell Cycle Quiescence Is Mediated by the Nuclear Hormone Receptor Coregulator DIN-1S in the Caenorhabditis elegans Dauer Larva.

    PubMed

    Colella, Eileen; Li, Shaolin; Roy, Richard

    2016-08-01

    When faced with suboptimal growth conditions, Caenorhabditis elegans larvae can enter a diapause-like stage called "dauer" that is specialized for dispersal and survival. The decision to form a dauer larva is controlled by three parallel signaling pathways, whereby a compromise of TGFβ, cyclic guanosine monophosphate, or insulin/IGF-like signaling (ILS) results in dauer formation. Signals from these pathways converge on DAF-12, a nuclear hormone receptor that triggers the changes required to initiate dauer formation. DAF-12 is related to the vitamin D, liver-X, and androstane receptors, and like these human receptors, it responds to lipophilic hormone ligands. When bound to its ligand, DAF-12 acquires transcriptional activity that directs reproductive development, while unliganded DAF-12 forms a dauer-specifying complex with its interacting protein DIN-1S to regulate the transcription of genes required for dauer development. We report here that din-1S is required in parallel to par-4/LKB1 signaling within the gonad to establish cell cycle quiescence during the onset of the dauer stage. We show that din-1S is important for postdauer reproduction when ILS is impaired and is necessary for long-term dauer survival in response to reduced ILS. Our work uncovers several previously uncharacterized functions of DIN-1S in executing and maintaining many of the cellular and physiological processes required for appropriate dauer arrest, while also shedding light on the coordination of nuclear hormone signaling, the LKB1/AMPK signaling cascade, and ILS/TGFβ in the control of cell cycle quiescence and tissue growth: a key feature that is often misregulated in a number of hormone-dependent cancers. PMID:27260305

  12. Inhibitory effect of UvrD and DinG on the replication of ColE1-derived plasmids in Escherichia coli.

    PubMed

    Kang, Nalae; Choi, Eunsil; Kim, Sung-Gun; Hwang, Jihwan

    2015-09-01

    CspA has been identified as a major cold-shock protein in Escherichia coli. CspA binds to RNAs which are abnormally folded at low temperature and then acts as an RNA chaperone unfolding those RNAs. The dramatic expression of cspA at low temperature is contributed by posttranscriptional stability and robust translatability. Interestingly, when cspA mRNA encoding a premature nonsense codon was overexpressed at low temperature, cell growth was completely inhibited. This phenotype was termed LACE (the low temperature-dependent antibiotic effect of truncated cspA expression), and this lethality resulted from exclusive stalling of most ribosomes on mutant cspA mRNAs. In a previous study, we demonstrated that overexpression of the ATP-dependent DNA helicases, UvrD and DinG, suppressed the lethality and ribosome stalling caused by mutant cspA mRNA. In the present study, we attempted to elucidate how these two DNA helicases help recover normal growth under LACE condition. Interestingly, we found that UvrD and DinG appeared to have an ability to down-regulate the replication of pUC-based high copy plasmid. In plasmid copy number tests, the amount of pUC-based plasmid encoding mutant cspA was reduced by 3-10-fold when either UvrD or DinG was expressed. Through a β-galactosidase activity assay, we also confirmed that expression of the lacZα gene inserted into the pUC-based plasmid was significantly reduced due to down-regulation of plasmid replication. Our findings imply that UvrD and DinG, known as non-replicative helicases, play a novel role in the regulation of ColE1-like plasmid replication.

  13. Land subsidence in the Cerro Prieto Geothermal Field, 1 Baja California, Mexico, from 1994 to 2005. An integrated analysis of DInSAR, levelingand geological data.

    SciTech Connect

    Sarychikhina, O; Glowacka, E; Mellors, R; Vidal, F S

    2011-03-03

    Cerro Prieto is the oldest and largest Mexican geothermal field in operation and has been producing electricity since 1973. The large amount of geothermal fluids extracted to supply steam to the power plants has resulted in considerable deformation in and around the field. The deformation includes land subsidence and related ground fissuring and faulting. These phenomena have produced severe damages to infrastructure such as roads, irrigation canals and other facilities. In this paper, the technique of Differential Synthetic Aperture Radar Interferometry (DInSAR) is applied using C-band ENVISAR ASAR data acquired between 2003 and 2006 to determine the extent and amount of land subsidence in the Mexicali Valley near Cerro Prieto Geothermal Field. The DInSAR results were compared with published data from precise leveling surveys (1994- 1997 and 1997-2006) and detailed geological information in order to improve the understanding of temporal and spatial distributions of anthropogenic subsidence in the Mexicali Valley. The leveling and DInSAR data were modeled to characterize the observed deformation in terms of fluid extraction. The results confirm that the tectonic faults control the spatial extent of the observed subsidence. These faults likely act as groundwater flow barriers for aquifers and reservoirs. The shape of the subsiding area coincides with the Cerro Prieto pull-apart basin. In addition, the spatial pattern of the subsidence as well as changes in rate are highly correlated with the development of the Cerro Prieto Geothermal Field.

  14. Land subsidence in the Cerro Prieto Geothermal Field, Baja California, Mexico, from 1994 to 2005: An integrated analysis of DInSAR, leveling and geological data

    NASA Astrophysics Data System (ADS)

    Sarychikhina, Olga; Glowacka, Ewa; Mellors, Robert; Vidal, Francisco Suárez

    2011-07-01

    Cerro Prieto is the oldest and largest Mexican geothermal field in operation and has been producing electricity since 1973. The large amount of geothermal fluids extracted to supply steam to the power plants has resulted in considerable deformation in and around the field. The deformation includes land subsidence and related ground fissuring and faulting. These phenomena have produced severe damages to the local infrastructure such as roads, irrigation canals and other facilities. In this paper, the technique of Differential Synthetic Aperture Radar Interferometry (DInSAR) is applied using C-band ENVISAR ASAR data acquired between 2003 and 2006 to determine the extent and amount of land subsidence in the Mexicali Valley near Cerro Prieto Geothermal Field. The DInSAR results were compared with published data from precise leveling surveys (1994-1997 and 1997-2006) and detailed geological information in order to improve understanding of the temporal and spatial distributions of anthropogenic subsidence in the Mexicali Valley. The leveling and DInSAR data were modeled to characterize the observed deformation in terms of fluid extraction. The results confirm that the tectonic faults control the spatial extent of the observed subsidence. These faults likely act as groundwater flow barriers for aquifers and reservoirs. The shape of the subsiding area coincides with the Cerro Prieto pull-apart basin. In addition, the changes in spatial pattern and rate of the subsidence are correlated with the development of the Cerro Prieto Geothermal Field.

  15. Recent experience with alloy 59-UNS N06059 (DIN No. 2.4605) in waste incineration plant components

    SciTech Connect

    Herda, W.R.; Roemer, W.

    1995-12-01

    The Federal Republic of Germany currently produces approximately 300 million tons of waste per year, which can be broadly characterized as follows: Waste from the producing sector -- approx. 121 million tons per year; Toxic and hazardous waste -- approx. 3 million tons per year; Building debris and waste -- approx. 131 million tons per year; Sewage sludge (dry weight) -- approx. 4 million tons per year; Miscellaneous urban waste (municipal and commercial waste, street refuse, market waste) -- approx. 41 million tons per year and commercial waste, street refuse, market waste. With waste landfill capacities reaching the exhaustion point and the land for further expansion becoming ever more scarce and expensive, it is essential to find another way of managing this problem. The cleanest and most viable technical solution available is thermal waste treatment using new environment friendly plants. This paper briefly discusses the objectives of thermal waste treatment, the current German laws and corrosion resistance characteristics and case histories of one of the newest and advanced alloys of the Ni-Cr-Mo family, Alloy 59-UNS N06059-(DIN No. 2.4605). Some economic analysis via cost comparisons is also presented.

  16. La dinámica demográfica y la desigualdad educativa en Méxicoa

    PubMed Central

    Giorguli Saucedo, Silvia E.; Vargas Valle, Eunice D.; Ulloa, Viviana Salinas; Hubert, Celia; Potter, Joseph E.

    2015-01-01

    En este trabajo se presenta una investigación sobre el vínculo entre los procesos educativos y la dinámica demográfica en México. La tradición del pensamiento sobre población y desarrollo ha partido de la hipótesis de que el ritmo de crecimiento poblacional, el tamaño de las familias y la migración influyen sobre la acumulación de capital humano entre la población en edades escolares. Se explora aquí la relación del desempeño educativo de los jóvenes entre 14 y 23 años y la razón de dependencia juvenil, la fecundidad adolescente y la migración interna e internacional; para ello se utilizan datos agregados a escala municipal del año 2000. El análisis incluye indicadores de la oferta educativa municipal basados en estadísticas administrativas de la SEP. PMID:26146427

  17. [Introduction of a quality management system compliant with DIN EN 9001:2000 in a university department of nuclear medicine].

    PubMed

    Jansen-Schmidt, V; Paschen, U; Kröger, S; Bohuslavizki, K H; Clausen, M

    2001-12-01

    In 1995, the management of the University Clinic Hamburg-Eppendorf proposed to establish a total quality assurance (QA) system. A revised QA-system has been introduced stepwise in the department of nuclear medicine since 1997, and certification was achieved in accordance with DIN EN ISO 9001:2000 on February 14, 2001. The QA-handbook is divided into two parts. The first part contains operational (diagnostic and therapeutic) procedures in so-called standard operating procedures (SOP). They describe the indication of procedures as well as the competences and time necessary in a standardized manner. Up to now, more than 70 SOPs have been written as a collaborative approach between technicians and physicians during daily clinical routine after analysing and discussing the procedures. Thus, the results were more clearly defined processes and more satisfied employees. The second part consists of general rules and directions concerning the security of work and equipment as well as radiation protection tasks, hygiene etc. as it is required by the law. This part was written predominantly by the management of the department of nuclear-medicine and the QA-coordinator. Detailed information for the patients, documentation of the work-flows as well as the medical report was adopted to the QM-system. Although in the introduction phase of a QA-system a vast amount of time is necessary, some months later a surplus for the clinical workday will become available. The well defined relations of competences and procedures will result in a gain of time, a reduction of costs and a help to ensure the legal demands. Last but not least, the QA-system simply helps to build up confidence and acceptance both by the patients and the referring physicians.

  18. Pre-eruptive ground deformation of Azerbaijan mud volcanoes detected through satellite radar interferometry (DInSAR)

    NASA Astrophysics Data System (ADS)

    Antonielli, Benedetta; Monserrat, Oriol; Bonini, Marco; Righini, Gaia; Sani, Federico; Luzi, Guido; Feyzullayev, Akper A.; Aliyev, Chingiz S.

    2014-12-01

    Mud volcanism is a process that leads to the extrusion of subsurface mud, fragments of country rocks, saline waters and gases. This mechanism is typically linked to hydrocarbon traps, and the extrusion of this material builds up a variety of conical edifices with a similar morphology to those of magmatic volcanoes, though smaller in size. The Differential Interferometry Synthetic Aperture Radar (DInSAR) technique has been used to investigate the ground deformation related to the activity of the mud volcanoes of Azerbaijan. The analysis of a set of wrapped and unwrapped interferograms, selected according to their coherence, allowed the detection of significant superficial deformation related to the activity of four mud volcanoes. The ground displacement patterns observed during the period spanning from October 2003 to November 2005 are dominated by uplift, which reach a cumulative value of up to 20 and 10 cm at the Ayaz-Akhtarma and Khara-Zira Island mud volcanoes, respectively. However, some sectors of the mud volcano edifices are affected by subsidence, which might correspond to deflation zones that coexist with the inflation zones characterized by the dominant uplift. Important deformation events, caused by fluid pressure and volume variations, have been observed both (1) in connection with main eruptive events in the form of pre-eruptive uplift, and (2) in the form of short-lived deformation pulses that interrupt a period of quiescence. Both deformation patterns show important similarities to those identified in some magmatic systems. The pre-eruptive uplift has been observed in many magmatic volcanoes as a consequence of magma intrusion or hydrothermal fluid injection. Moreover, discrete short-duration pulses of deformation are also experienced by magmatic volcanoes and are repeated over time as multiple inflation and deflation events.

  19. [The "Hersbruck Model". Application and integration of the DIN EN ISO 9001 quality norms with criteria of the European Foundation for Quality Management in a clinic].

    PubMed

    Fritze, B; Amon, U

    1999-11-01

    The german health system has dramatically changed and still continues to do so. Modified aspects concerning economy, customer orientation, competition, quality assurance and quality management seem to be increasingly important. Appropriate response to this challenge demands a relevant adjustment of a quality "philosophy" within a hospital. The "Hersbruck Model" has proven to be a suitable approach: on the basis of a quality management system--established and certified according to DIN EN ISO 9001--it implements all components of the model of the European Foundation for Quality Management. The modern quality tools as Total Quality Management and continuous quality improvement allow a permanent increase of customer/patient satisfaction.

  20. The contribute of DInSAR techniques to landslide hazard evaluation in mountain and hilly regions: a case study from Agno Valley (North-Eastern Italian Alps)

    NASA Astrophysics Data System (ADS)

    De Agostini, A.; Floris, M.; Pasquali, P.; Barbieri, M.; Cantone, A.; Riccardi, P.; Stevan, G.; Genevois, R.

    2012-04-01

    In the last twenty years, Differential Synthetic Aperture Radar Interferometry (DInSAR) techniques have been widely used to investigate geological processes, such as subsidence, earthquakes and landslides, through the evaluation of earth surface displacements caused by these processes. In the study of mass movements, contribution of interferometry can be limited due to the acquisition geometry of RADAR images and the rough morphology of mountain and hilly regions which represent typical landslide-prone areas. In this study, the advanced DInSAR techniques (i.e. Small Baseline Subset and Persistent Scatterers techniques), available in SARscape software, are used. These methods involve the use of multiple acquisitions stacks (large SAR temporal series) allowing improvements and refinements in landslide identification, characterization and hazard evaluation at the basin scale. Potential and limits of above mentioned techniques are outlined and discussed. The study area is the Agno Valley, located in the North-Eastern sector of Italian Alps and included in the Vicenza Province (Veneto Region, Italy). This area and the entire Vicenza Province were hit by an exceptional rainfall event on November 2010 that triggered more than 500 slope instabilities. The main aim of the work is to verify if spatial information available before the rainfall event, including ERS and ENVISAT RADAR data from 1992 to 2010, were able to predict the landslides occurred in the study area, in order to implement an effectiveness forecasting model. In the first step of the work a susceptibility analysis is carried out using landslide dataset from the IFFI project (Inventario Fenomeni Franosi in Italia, Landslide Italian Inventory) and related predisposing factors, which consist of morphometric (elevation, slope, aspect and curvature) and non-morphometric (land use, distance of roads and distance of river) factors available from the Veneto Region spatial database. Then, to test the prediction, the

  1. 3D Faulting Numerical Model Related To 2009 L'Aquila Earthquake Based On DInSAR Observations

    NASA Astrophysics Data System (ADS)

    Castaldo, Raffaele; Tizzani, Pietro; Solaro, Giuseppe; Pepe, Susi; Lanari, Riccardo

    2014-05-01

    We investigate the surface displacements in the area affected by the April 6, 2009 L'Aquila earthquake (Central Italy) through an advanced 3D numerical modeling approach, by exploiting DInSAR deformation velocity maps based on ENVISAT (Ascending and Descending orbits) and COSMO-SkyMed data (Ascending orbit). We benefited from the available geological and geophysical information to investigate the impact of known buried structures on the modulation of the observed ground deformation field; in this context we implemented the a priori information in a Finite Element (FE) Environment considering a structural mechanical physical approach. The performed analysis demonstrate that the displacement pattern associated with the Mw 6.3 main-shock event is consistent with the activation of several fault segments of the Paganica fault. In particular, we analyzed the seismic events in a structural mechanical context under the plane stress mode approximation to solve for the retrieved displacements. We defined the sub-domain setting of the 3D FEM model using the information derived from the CROOP M-15 seismic line. We assumed stationarity and linear elasticity of the involved materials by considering a solution of classical equilibrium mechanical equations. We evolved our model through two stages: the model compacted under the weight of the rock successions (gravity loading) until it reached a stable equilibrium. At the second stage (co-seismic), where the stresses were released through a slip along the faults, by using an optimization procedure we retrieved: (i) the active seismogenic structures responsible for the observed ground deformation, (ii) the effects of the different mechanical constraints on the ground deformation pattern and (iii) the spatial distribution of the retrieved stress field. We evaluated the boundary setting best fit configuration responsible for the observed ground deformation. To this aim, we first generated several forward structural mechanical models

  2. Using Radar Interferometry (DinSAR) to Evaluate Land Subsidence Caused by Excessive Groundwater Withdrawal in Morocco

    NASA Astrophysics Data System (ADS)

    Durham, M. C.; Milewski, A.; El Kadiri, R.

    2013-12-01

    The combination of natural, anthropogenic, and climate change impacts on the water resources of the Middle East and North Africa (MENA) region has devastated its water resources well beyond its current and projected populations. The increased exploitation of groundwater resources in the past half-century coupled with successive droughts has resulted in the acceleration of subsidence rates in the Souss and Massa basins in Morocco. We have completed a preliminary investigation of these impacts on the Souss and Massa basins (~27,000 km2) in the southwestern part of Morocco. This area is characterized by a semi-arid climate (annual precipitation 70-250 mm/year) with agriculture, tourism, and commercial fishing as the primary economic activities, all of which require availability of adequate freshwater resources. Additionally the primary groundwater aquifer (Plio-Quaternary Plain Aquifer), an unconfined aquifer formed mostly of sand and gravel, is being harvested by >20,000 wells at a rate of 650 MCM/yr., exceeding the rate of recharge by 260 MCM/year. Intense development over the past 50 years has exposed the aquifer to a serious risk of groundwater table drawdown (0.5m-2.5m/yr.), land subsidence, loss of artesian pressure, salinization, salt water intrusions along the coast, and deterioration of water quality across the watershed. Differential Interferometry Synthetique Aperture Radar (DInSAR) was utilized to measure ground subsidence induced by groundwater withdrawal. Land subsidence caused by excessive groundwater extraction was determined using a threefold methodology: (1) extraction of subsidence and land deformation patterns using radar interferometry, (2) correlation of the high subsidence areas within the basins to possible natural and anthropogenic factors (e.g. sea level rise, unconsolidated lithological formations distribution, urbanization, excessive groundwater extraction), and (3) forecasting the future of the Souss and Massa basins over the next century

  3. Caractérisations structurale et morphologique des couches minces de CuInS2 et d'In-S "airless spray"

    NASA Astrophysics Data System (ADS)

    Kamoun, N.; Belgacem, S.; Amlouk, M.; Bennaceur, R.; Abdelmoula, K.; Belhadj Amara, A.

    1994-03-01

    We have prepared CuInS2 thin layers by airless spray "S.P.A." in order to use them as an absorber in a photovoltaic cell. The X-ray diffraction analysis has showed that these layers are well crystallized with a privileged (112) principal orientation for a ratio of the concentrations in the pulverized solution x=frac[Cu^I][In^{III]}=1.1. After heat treatment under vacuum the crystallization have been clearly improved. The structural analysis of the thin CuInS2 layers have revealed that a secondary phases of In2S3 and In6S7 are present. Thus we have realized by the same technique thin In-S layers whose structural and morphological properties have been studied. This analysis has showed that the In-S layers are well crystallized for a ratio y=frac[In^{3+]}[S^{2-]}=0.6 in the spray solution. The In-S layers are essentially formed by a β-In2S3 material. Although the In6S7 phase appears to the detriment of β-In2S3 phase for y= 0.75. Nous avons préparé des couches minces de CuInS2, par pulvérisation chimique réactive sans air "P.S.A.", en vue de leur utilisation en tant qu'absorbeur dans un dispositif photovoltaïque. L'analyse par diffraction X a montré que ces couches sont bien cristallisées et que l'orientation principale (112) est privilégiée pour un rapport de concentrations x=frac[Cu^I]{[In^{III}]}=1,1 dans la solution à pulvériser. Après le traitement thermique sous vide la cristallisation est nettement améliorée. L'analyse structurale des couches minces de CuInS2 a révélé que ces couches renferment des phases secondaires d'In2S3 et d'In6S7. Ainsi nous avons réalisé par la même technique "P.S.A.", des couches minces d'In-S dont nous avons étudié les propriétés structurales et morphologiques, Cette analyse a montré que les couches d'In-S sont bien cristallisées. Pour un rapport de concentrations en solution de pulvérisation y=frac[In^{3+]}[S^{2-]}=0,6 les couches d'In-S sont surtout formées du matériau β-In2S3. Alors que la phase In6S7

  4. Monitoring of land subsidence in Ravenna Municipality using two different DInSAR techniques: comparison and discussion of the results.

    NASA Astrophysics Data System (ADS)

    Fiaschi, Simone; Di Martire, Diego; Tessitore, Serena; Achilli, Vladimiro; Ahmed, Ahmed; Borgstrom, Sven; Calcaterra, Domenico; Fabris, Massimo; Ramondini, Massimo; Serpelloni, Enrico; Siniscalchi, Valeria; Floris, Mario

    2015-04-01

    Land subsidence affecting the Ravenna Municipality (Emilia Romagna Region, NE Italy) is one of the best example on how the exploitation of natural resources can affect the environment and the territory. In fact, the pumping of groundwater and the extraction of gas from both on and off-shore reservoirs, started in the 1950s, have caused a strong land subsidence affecting most of the Emilia Romagna territory but in particular the Adriatic Sea coastline near Ravenna. In such area the current subsidence rate, even if lower than in the past, can reach the -2cm/y. Local Authorities have monitored this phenomenon over the years with different techniques: spirit levelling, GPS surveys and, more recently, Interferometric Synthetic Aperture Radar (InSAR) techniques, confirming the critical situation of land subsidence risk. In this work, we present the comparison between the results obtained with two different DInSAR techniques applied to the study of the land subsidence in the Ravenna territory: the Small Baseline Subset (SBAS) and the Coherent Pixel Technique (CPT) techniques. The SBAS works on SARscape software and is based on the Berardino et al., 2002 algorithm. This technique relies on the combination of differential interferograms created from stacks of SAR image pairs that have small temporal and perpendicular baselines. Thanks to the application of several interferograms for every single image, it is possible to obtain high spatial coherence, high data density and more effective error reduction. This allows us to obtain mean velocity maps with good data density even over non-urbanized territories. For the CPT we used the SUBsoft processor based on the algorithm implemented by Mora et al., 2003. CPT is able to extract from a stack of differential interferograms the deformation evolution over wide areas during large time spans. The processing scheme is composed of three main steps: a) the generation of the best interferogram set among all the available images of the

  5. Integrated analysis of differential interferometric synthetic aperture radar (DInSAR) and geological data for measuring deformation movement of Kaligarang fault, Semarang-Indonesia

    NASA Astrophysics Data System (ADS)

    Prasetyo, Y.; Fakhrudin, Warasambi, S. M.

    2016-05-01

    Semarang is one of the densely populated city in Central Java which is has Kaligarang's fault. It is lie in Kaligarang River and across several dense urban settlement. The position of Kaligarang's river itself divides in the direction nearly north-south city of Semarang. The impact of the fault can be seen in severals indication such as a land subsidence phenomenon in Tinjomoyo village area which is make impact to house and road destruction. In this research, we have used combination methods between InSAR, DinSAR and geomorphology (geology data) where is this techniques used to identity the fault area and estimate Kaligarang's fault movement velocity. In fault movement velocity observation, we only compute the movement in vertical with neglect horizontal movement. The data used in this study of one pair ALOS PALSAR level 1.0 which was acquired on June 8, 2007and 10 of September 2009. Besides that third ALOS PALSAR earlier, also used data of SRTM DEM 4th version, is used for the correction of the topography. The use of the three methods already mentioned earlier have different functions. For the lnSAR method used for the establishment of a digital model in Semarang. After getting high models digital city of Semarang, the identification process can be done layout, length, width and area of the Kaligarang fault using geomorphology. Results of such identification can be calculated using the rate of deformation and fault movement. From the result generated DinSAR method of land subsidence rate between 3 em to II em. To know the truth measurement that used DinSAR method, is performed with the decline of validation that measured using GPS. After validating obtained standard deviation of 3,073 em. To estimate the Kaligarang's fault pattern and direction is using the geomorphology method. The results that Kaligarang's is an active fault that has fault strike slip as fault pattern. It makes this research is useful because could be used as an inquick assessment in fault

  6. A model for the abrogation of the SOS response by an SOS protein: a negatively charged helix in DinI mimics DNA in its interaction with RecA

    PubMed Central

    Voloshin, Oleg N.; Ramirez, Benjamin E.; Bax, Ad; Camerini-Otero, R. Daniel

    2001-01-01

    DinI is a recently described negative regulator of the SOS response in Escherichia coli. Here we show that it physically interacts with RecA and prevents the binding of single-stranded DNA to RecA, which is required for the activation of the latter. DinI also displaces ssDNA from a stable RecA–DNA cofilament, thus eliminating the SOS signal. In addition, DinI inhibits RecA-mediated homologous DNA pairing, but has no effect on actively proceeding strand exchange. Biochemical data, together with the molecular structure, define the C-terminal α-helix in DinI as the active site of the protein. In an unusual example of molecular mimicry, a negatively charged surface on this α-helix, by imitating single-stranded DNA, interacts with the loop L2 homologous pairing region of RecA and interferes with the activation of RecA. PMID:11230150

  7. Analysis of the deep-seated gravitational slope deformations over Mt. Frascare (Central Italy) with geomorphological assessment and DInSAR approaches

    NASA Astrophysics Data System (ADS)

    Tolomei, C.; Taramelli, A.; Moro, M.; Saroli, M.; Aringoli, D.; Salvi, S.

    2013-11-01

    A quantitative and innovative DGSD (deep gravitational slope deformation) assessment method that used integrated remote sensing was tested in the central Apennine mountain range (Italy). The movement rate was calculated for selected test areas using the differential SAR interferometry small baseline subset (SBAS) technique. The selected test areas were previously identified by interpreting both aerial photos and using 32 ERS radar images taken between 1993 and 2000. More than 15 cm of cumulative surface displacement occurred across the Podalla DGSD along the satellite line of sight (LoS). Moreover, the displacement time series showed non-linear deformation rates, which included periods of accelerated movement correlated with strong rainfall. The high estimated Podalla DGSD activity indicates that this type of study should be conducted to monitor the evolution of this phenomenon. In addition, the DInSAR movement rate can be used to improve mapping and identify DGSDs in specific landscapes.

  8. [Customer satisfaction with a quality management system according to DIN EN ISO 9001:2000: Increase in the satisfaction of cooperating clinics].

    PubMed

    Beholz, Sven; Konertz, Wolfgang

    2006-01-01

    The evaluation of customers' satisfaction is elementary for any quality management system. In our university cardiac surgery unit that has been certified according to DIN EN ISO 9001:2000 the influence of repeated evaluation of the referring physicians' satisfaction conducted in the course of three consecutive years on structures and processes in the scope of the quality management system was examined. Customers' satisfaction with the possibility of access to the department could be increased by targeted interventions. Further interventions in the field of documentation led to a measurable increase in satisfaction with postoperative communication. Repeated annual evaluation of the satisfaction of referring physicians has proved to be a valuable tool in the process of continuous quality improvement.

  9. Espectroscopia multi-objeto e imageamento de Abell 586 com GMOS - o estado dinâmico de um aglomerado de galáxias com arcos gravitacionais

    NASA Astrophysics Data System (ADS)

    Cypriano, E. S.; Sodrã©, L., Jr.; Kneib, J.-P.; Campusano, L.

    2003-08-01

    Nesse trabalho é apresentado um estudo do conteúdo de massa do aglomerado de galáxias A586 (z = 0.171) bem como sua distribuição espacial. Isso foi feito a partir de dados de espectroscopia multi-objeto e imageamento obtidos com o instrumento GMOS acoplado ao telescópio Gemini-Norte. A massa desse aglomerado foi estudada a partir da posição dos seus arcos gravitacionais (lentes fortes), da medida estatística da distorção na forma das galáxias de fundo (lentes fracas) e através da dispersão de velocidades de uma amostra de cerca de 30 galáxias pertencentes ao aglomerado (teorema do virial). Os dois primeiros métodos não dependem do estado dinâmico do aglomerado, enquanto que o terceiro sim. Desse modo, comparando seus resultados pode-se estimar o grau de relaxamento desse sistema. Dados de raios X presentes na literatura também serão incluídos nessa análise. Nossos resultados preliminares a partir das técnicas de lentes fracas, mostram que, supondo que a distribuição de massa desse aglomerado seja a de uma esfera isotérmica, espera-se que ele apresente uma dispersão de velocidades de 1330+/-78 km s-1, em contradicao com medidas similares feitas por Dahle et al. 2002 que encontram valores tão altos quanto 1680 km s-1. Já o estudo dinâmico resultou numa dispersão de velocidades de ~950 km s-1.

  10. Monitoring of surface deformation in open pit mine using DInSAR time-series: a case study in the N5W iron mine (Carajás, Brazil) using TerraSAR-X data

    NASA Astrophysics Data System (ADS)

    Mura, José C.; Paradella, Waldir R.; Gama, Fabio F.; Santos, Athos R.; Galo, Mauricio; Camargo, Paulo O.; Silva, Arnaldo Q.; Silva, Guilherme G.

    2014-10-01

    We present an investigation of surface deformation using Differential SAR Interferometry (DInSAR) time-series carried out in an active open pit iron mine, the N5W, located in the Carajás Mineral Province (Brazilian Amazon region), using 33 TerraSAR-X (TSX-1) scenes. This mine has presented a historical of instability and surface monitoring measurements over sectors of the mine (pit walls) have been done based on ground based radar. Two complementary approaches were used: the standard DInSAR configuration, as an early warning of the slope instability conditions, and the DInSAR timeseries analysis. In order to decrease the topographic phase error a high resolution DEM was generated based on a stereo GeoEye-1 pair. Despite the fact that a DinSAR contains atmospheric and topographic phase artifacts and noise, it was possible to detect deformation in some interferometric pairs, covering pit benches, road ramps and waste piles. The timeseries analysis was performed using the 31 interferometric pairs, which were selected based on the highest mean coherence of a stack of 107 interferograms, presenting less phase unwrapping errors. The time-series deformation was retrieved by the Least-Squares (LS) solution using an extension of the Singular Value Decomposition (SVD), with a set of additional weighted constrain on the acceleration deformation. The atmospheric phase artifacts were filtered in the space-time domain and the DEM height errors were estimated based on the normal baseline diversity. The DInSAR time-series investigation showed good results for monitoring surface displacement in the N5W mine located in a tropical rainforest environment, providing very useful information about the ground movement for alarm, planning and risk assessment.

  11. 3D displacements maps of the L'Aquila earthquake by applying SISTEM method to GPS and ENVISAT and ALOS DInSAR data

    NASA Astrophysics Data System (ADS)

    Guglielmino, Francesco; Anzidei, Marco; Briole, Pierre; de Michele, Marcello; Elias, Panagiotis; Nunnari, Giuseppe; Puglisi, Giuseppe; Spata, Alessandro

    2010-05-01

    We present an application of the novel SISTEM (Simultaneous and Integrated Strain Tensor Estimation from geodetic and satellite deformation Measurements) approach [Guglielmino et al., 2009] to obtain a 3D estimation of the ground deformation pattern produced by the April 6, 2009, Mw 6.3 L'Aquila earthquake, the most destructive in the Abruzzo region since the huge 1703 earthquake [Boschi et al., 2000; Chiarabba et al., 2005]. The focal mechanism of the main shock is of normal faulting with NE-SW oriented T-axis [INGV, 2009]. Most of the aftershocks, located by the INGV seismic network, are in the depth range 5÷15 km, depicting a SW dipping fault plane [INGV, 2009]. Field observations [EMERGEO working group, 2009] have identified surface ground cracks with centimeter to decimeters throws over a wide belt running along the Paganica Fault. A closely spaced GPS (Global Positioning System) network was set up in this sector of the Apennines after 1999 [Anzidei et al., 2005] and more than 10 Continuous GPS (CGPS) stations have been operating in this region over the last years. On March 30 2008, INGV installed five GPS receivers on selected benchmarks of the Central Apennine Geodetic Network (CaGeoNet) bordering the L'Aquila basin in order to detect the eventual ground movements during the seismic sequence. These stations were crucial to resolve the near-field co-seismic deformation pattern properly, allowing direct observation of the details of co-seismic displacement related to the main shock. Thanks to the ESA Earth Watching project, which made Envisat data quickly available after their acquisition, we performed a DInSAR (Differential Interferometric Synthetic Aperture Radar) analysis of ascending and descending images sampling the date of the earthquake. In particular, we analyze the descending pair for the interval 27/04/2008 - 12/04/2009 (tbline = 350 days; Bperp = 44m) and the ascending pair for the interval 11/03/2009 - 15/04/2009 (tbline = 35 days; Bperp = 227m

  12. 3D displacements maps of the L'Aquila earthquake by applying SISTEM method to GPS and ENVISAT and ALOS DInSAR data

    NASA Astrophysics Data System (ADS)

    Guglielmino, Francesco; Anzidei, Marco; Briole, Pierre; de Michele, Marcello; Elias, Panagiotis; Nunnari, Giuseppe; Puglisi, Giuseppe; Spata, Alessandro

    2010-05-01

    We present an application of the novel SISTEM (Simultaneous and Integrated Strain Tensor Estimation from geodetic and satellite deformation Measurements) approach [Guglielmino et al., 2009] to obtain a 3D estimation of the ground deformation pattern produced by the April 6, 2009, Mw 6.3 L'Aquila earthquake, the most destructive in the Abruzzo region since the huge 1703 earthquake [Boschi et al., 2000; Chiarabba et al., 2005]. The focal mechanism of the main shock is of normal faulting with NE-SW oriented T-axis [INGV, 2009]. Most of the aftershocks, located by the INGV seismic network, are in the depth range 5÷15 km, depicting a SW dipping fault plane [INGV, 2009]. Field observations [EMERGEO working group, 2009] have identified surface ground cracks with centimeter to decimeters throws over a wide belt running along the Paganica Fault. A closely spaced GPS (Global Positioning System) network was set up in this sector of the Apennines after 1999 [Anzidei et al., 2005] and more than 10 Continuous GPS (CGPS) stations have been operating in this region over the last years. On March 30 2008, INGV installed five GPS receivers on selected benchmarks of the Central Apennine Geodetic Network (CaGeoNet) bordering the L'Aquila basin in order to detect the eventual ground movements during the seismic sequence. These stations were crucial to resolve the near-field co-seismic deformation pattern properly, allowing direct observation of the details of co-seismic displacement related to the main shock. Thanks to the ESA Earth Watching project, which made Envisat data quickly available after their acquisition, we performed a DInSAR (Differential Interferometric Synthetic Aperture Radar) analysis of ascending and descending images sampling the date of the earthquake. In particular, we analyze the descending pair for the interval 27/04/2008 - 12/04/2009 (tbline = 350 days; Bperp = 44m) and the ascending pair for the interval 11/03/2009 - 15/04/2009 (tbline = 35 days; Bperp = 227m

  13. Synergy of ASAR and RADARSAT-2 ultra-fine acquisitions for ground deformation monitoring by means of DInSAR and PSI

    NASA Astrophysics Data System (ADS)

    Elias, Panagiotis; Briole, Pierre; Sykioti, Olga

    2010-05-01

    consideration the raised seismisity of the area. The Psathopyrgos fault zone as well as the Rion-Patras transfer fault zone are investigated for any detectable ground deformations that could be indications/precursors or inter-seismic accumulation processes before a main event. The city of Patras are investigated for any detectable ground/buildings deformation due to human interventions or geophysical processes. The potential of Rion-Antirion bridge monitoring for any detectable deformation as well as the surrounding ground on the two edges of it, are also investigated and assessed. The study area presents major difficulties for DInSAR/PSI applications, due to its intense vegetation coverage and high topography presenting various facets, varying high slopes and shadowing effects. Moreover its intense topography in conjunction with its location between Aegean and Ionian seas is leading to high precipitation rates and extend cloud coverage. All these characteristics of the study area contribute to high decorrelation of the interferometric products. For the estimation of the ocuured deformations a series of ASAR/ENVISAT (image swath 2) data are processed by means of PSI and DInSAR techniques, but RADARSAT-2 (ultra-fine beam mode) data are processed only by means of DInSAR technique due to its lack of historical data. The processing will be carried out exploiting commercial and in-house software. The medium and high ground resolution added value products of the acquired data are combined in the thematic level.

  14. Interplay Between Tectonics And Volcanic Processes Active In The Yellowstone Caldera Detected Via DInSAR And GPS Time-Series

    NASA Astrophysics Data System (ADS)

    Tizzani, Pietro; Battaglia, Maurizio; Castaldo, Raffaele; Pepe, Antonio; Zeni, Giovanni; Lanari, Riccardo

    2014-05-01

    We discriminate and quantify the effects of different stress sources that are active in the Yellowstone volcanic region. In particular, the use of long-term deformation time series allows us to separate the spatial and temporal contributions of the regional tectonic field due to North American (NA) plate motion from the dynamic of magmatic/hydrothermal sources beneath the caldera area. Yellowstone volcano was formed by three major caldera forming eruptions that occurred around 2.0, 1.3 and 0.64 Ma, the most recent one responsible for the 60 km-wide and 40 km-long Yellowstone caldera. Two structural resurgent domes emerged after the last caldera forming eruption: the Mallard Lake (ML) resurgent dome in the southwestern region of Yellowstone caldera, and the Sour Creek (SC) resurgent dome in the northeast part of the caldera. In this work, we extensively exploit DInSAR and GPS measurements to investigate surface deformation at Yellowstone caldera over the last 18 years. We start by analyzing the 1992-2010 deformation time series retrieved by applying the Small BAseline Subset (SBAS) DInSAR technique. This allows us identifying three macro-areas: i) Norris Geyser Basin (NGB), ii) ML and SC resurgent domes and iii) Snake River Plain (SRP), characterized by unique deformation behaviors. In particular, SRP shows a signal related to tectonic deformation, while the other two regions are influenced by the caldera unrest. To isolate the deformation signals related to different stress sources in the Yellowstone caldera, we also remove from the retrieved mean deformation velocity maps the mean displacement rate associated to the northern sector of the Snake River Plain. This latter is the result of tectonic processes controlled by complex interactions between the NA plate, moving in the ENE - WSW direction with a rate of about 2 cm/yr, and the flow of the asthenosphere plume beneath the Yellowstone volcanic region. These de-trended data allow recognizing four major deformation

  15. Comparison of water-level, extensometric, DInSAR and simulation data for quantification of subsidence in Murcia City (SE Spain)

    NASA Astrophysics Data System (ADS)

    Tessitore, S.; Fernández-Merodo, J. A.; Herrera, G.; Tomás, R.; Ramondini, M.; Sanabria, M.; Duro, J.; Mulas, J.; Calcaterra, D.

    2016-05-01

    Subsidence due to groundwater overexploitation has been recognized in the metropolitan area of Murcia (25 km2) in south-eastern Spain since the early 1990s. Previous published works have focused their attention on land subsidence that occurred during the drought period between 1995 and 2008. This work first analyzes the groundwater recovery that has occurred since 2008 and then determines the kind of associated ground deformation detected by the new extensometric data. Subsequently, subsidence time series are computed on 24 geotechnical boreholes scattered throughout the study area by means of a hydro-mechanical finite element code and a linear-elastic constitutive law. A spatio-temporal interpolation of the numerically modeled surface displacements is performed over the whole domain and compared with extensometers and DInSAR-derived displacement maps in two different periods: the drought period from 2004 to 2008, and the recovery period from 2008 to 2012. In spite of the limited information on the geomechanical parameters characterizing the modelled geological formations, the proposed approach is able to discriminate areas where the soils have an elastic behavior (small differences in the comparisons) or an elasto-plastic behavior (large differences in the comparisons). This zonation enhances the understanding of the subsidence phenomenon in Murcia City and could prevent, from a quantitatively point of view, future severe subsidence due to aquifer overexploitation.

  16. The major event of the 1997 Umbria-Marche (Italy) sequence: what could we learn from DInSAR and GPS data?

    NASA Astrophysics Data System (ADS)

    Belardinelli, M. E.; Sandri, L.; Baldi, P.

    2003-04-01

    The main event of the Umbria-Marche (Central Italy) sequence was an MW= 6 earthquake following another MW= 5.7 event that had occurred a few hours before. Two kinds of geodetic data enable us to image the coseismic displacement field related to these two earthquakes: GPS measurements over several points in the area and the vertical displacement field provided by DInSAR interferometry with respect to a preseismic stage. Both measurements were taken approximately 15 days after the main shock. Other two MW > 5 earthquakes occurred nearby, 6 and 9 days after the main shock, also contributed to the observed displacement field. The present study of the main structure involved in this sequence is based on the comparison between a dislocation model that is as simplified as possible and both kinds of deformational data. The seismogenic structures involved in the four events were described by several studies, made before the present one, where reference is also made to seismological evidence. The previously obtained inferences of fault geometry (length, width and slip heterogeneity) concerning the main event of the Umbria-Marche sequence are used here as a starting model. Compared with previous analyses of the same measurements, the present study identifies to what extent each fault parameter is constrained by the data, quantifying the uncertainties associated with its estimated value.

  17. General design method for 3-dimensional, potential flow fields. Part 2: Computer program DIN3D1 for simple, unbranched ducts

    NASA Technical Reports Server (NTRS)

    Stanitz, J. D.

    1985-01-01

    The general design method for three-dimensional, potential, incompressible or subsonic-compressible flow developed in part 1 of this report is applied to the design of simple, unbranched ducts. A computer program, DIN3D1, is developed and five numerical examples are presented: a nozzle, two elbows, an S-duct, and the preliminary design of a side inlet for turbomachines. The two major inputs to the program are the upstream boundary shape and the lateral velocity distribution on the duct wall. As a result of these inputs, boundary conditions are overprescribed and the problem is ill posed. However, it appears that there are degrees of compatibility between these two major inputs and that, for reasonably compatible inputs, satisfactory solutions can be obtained. By not prescribing the shape of the upstream boundary, the problem presumably becomes well posed, but it is not clear how to formulate a practical design method under this circumstance. Nor does it appear desirable, because the designer usually needs to retain control over the upstream (or downstream) boundary shape. The problem is further complicated by the fact that, unlike the two-dimensional case, and irrespective of the upstream boundary shape, some prescribed lateral velocity distributions do not have proper solutions.

  18. [Microbiological research methods of drinking water regulation in West Germany from 1986. Suitability of the specifications of DIN 38411, Part 7, for the detection of sulfite-reducing, spore-forming anaerobes (Clostridia)].

    PubMed

    Schneider, J; Edenharder, R; Borneff, J

    1988-01-01

    The drinking-water regulations of the Federal Republic of Germany, from 22.05.1986, contains in paragraph 1 the instructions: "Drinking-water must be free of pathogens", and further in paragraph 11, "Responsibilities of the employer or other owner of a water supplying facility", include that: "The official authority may direct, that the employer...of a water supplying facility has to extend or has to cause to extend the microbiological examinations in order to determine, that...sulfite-reducing, spore-forming anaerobes (Clostridia) can not be detected in 20 ml of water..." The drinking-water regulations do not prescribe a bacteriological examination method in detail. Appendix 1 rules only that the examination for sulfite-reducing, spore-forming anaerobes (Clostridia) has to be performed after heating the sample to 75 degrees C (+/- 5 degrees C) for 10 min, by either the multiple-tube or membrane filtration method and cultivation in DRCM1-medium. If growth occurs, the presence of Clostridia must be confirmed by anaerobic and aerobic subcultivation. Furthermore, a DIN-instruction (DIN 38411, part 7) exists, which prescribes a detailed procedure for multiple-tube and membrane filtration methods, but does not provide for strict anaerobiosis. We were, however, unable to detect Clostridia in a multitude of water samples with the methods of the DIN-regulation. In order to examine if neglect of strict anaerobiosis was the reason for these failures, we checked the suitability of the DIN-regulation for the isolation of Clostridia from drinking water. In preliminary tests we examined up to four strains of the species C. botulinum, C. cadaveris, C. cochlearium, C. difficile, C. innocuum, C. perfringens and C. tertium for their ability to form heat-resistent spores in four sporulation media. It was, however, not possible to find a medium, in which all strains could sporulate within one week. In order to characterize the detection of these anaerobes in water, one particularly

  19. La estructura dinámica del cinturón de Kuiper interior y la formación de Urano y Neptuno

    NASA Astrophysics Data System (ADS)

    Melita, M. D.; Brunini, A.

    De acuerdo a los más recientes estudios sobre la formación de Urano y Neptuno, éstos podrían haber sufrido una importante migración radial hacia el exterior, debido al intercambio de momento angular con los planetesimales presentes en esa región durante las últimas etapas de la formación del Sistema Solar. Esta migración radial habría tenido importantes consecuencias sobre la presente estructura dinámica del cinturón cometario de Kuiper. Tal como lo reflejan las observaciones, la mayoría de los cuerpos observados en el cinturón de Kuiper se encuentran en resonancia de movimientos medios exteriores con Neptuno, hecho que también se refleja en la presente órbita de Plutón. En el presente trabajo se estudia tanto numérica como analíticamente la influencia de la variación de las masas de Urano y Neptuno durante el proceso de migración sobre las probabilidades de captura en algunas de las resonancias exteriores de Neptuno. Se estudia también la influencia de encuentros gravitacionales mutuos sobre la estabilidad de las órbitas resonantes. Este estudio ofrece argumentos de plausibilidad para explicar por qué ninguno de los objetos descubiertos en el cinturón de Kuiper se encontraría en la resonancia 2:1.

  20. Correlation between pore fluid pressures and DInSAR post-seismic deformation of the May 20, 2012 Emilia-Romagna (Italy) earthquake

    NASA Astrophysics Data System (ADS)

    Moro, M.; Stramondo, S.; Albano, M.; Barba, S.; Solaro, G.; Saroli, M.; Bignami, C.

    2015-12-01

    The present work focuses on the detection and analysis of the postseismic surface deformations following the two earthquakes that hit the Emilia Romagna region (Italy) on May 20 and 29, 2012. The 2012 Emilia earthquake sequence struck the central sector of the Ferrara arc, which represents the external fold-and-thrust system of the Northern Apennines thrust belt buried below the Po plain. The May 20 event occurred on the Ferrara basal thrust at depth, at about 6-7 km, while, during the May 29 event, the rupture jumped on an inner splay of the Ferrara system. The analysis of the postseismic displacements was carried out thanks to a dataset of SAR COSMO­ SkyMed images covering a time span of about one year (May 20, 2012 - May 11, 2013) after the May 20 event. The DInSAR results revealed the presence of two deformation patches: the first one is located in the area that experienced the coseismic uplift. Here the postseismic displacements point out a further ground uplift occurring along the first three months after the 20 May event. The second deformation patch is located in the villages of San Carlo and Mirabello, where ground subsidence lasting about four months was detected. We hypothesized that both the observed phenomena are related to the pore pressure perturbation caused by the coseismic deformation. In particular, the ground uplift is due to the deep crustal deformations caused by the pore fluid diffusion at depth to re-establish the initial hydrostatic stresses. Instead, the ground subsidence is related to the compaction of the shallow sandy layers caused by the liquefaction phenomena, which widely affected the San Carlo and Mirabello area. Preliminary numerical analyses performed with the Finite Element Method and empirical relations confirmed our hypothesis.

  1. Etude des propriétés optiques des couches minces de CuInS2 et d'In-S " Airless spray "

    NASA Astrophysics Data System (ADS)

    Kamoun, N.; Bennaceur, R.; Frigerio, J. M.

    1994-05-01

    In this work we have studied the optical properties of the thin CuInS2 and In-S layers prepared by airless spray " P.S.A. ". The study of the optical properties from the ellipsometric measure realized in the interval energy of incident photons [1.5-4] eV, has showed that the refraction index n_1 and the extinction coefficient k_1 vary in the interval [1.8-2.3] and [0.45-0.80] respectively. The absorption coefficient α of the thin CuInS2 layers realized for different ratios x of the concentrations in the spray solution (x =frac[CuI][InIII]) is high with values varied between (5 × 10^4 and 18 × 10^4 cm^{-1}). The direct gap energy of the thin CuInS2 layers of the order of 1.38 eV. In the same way, we study the spectrum variation of n_1 (λ) and k_1 (λ) of the thin In-S layers, realized for two values of ratio y of the concentration in the spray solution (y=frac{[In^{3+}]}{[S^{2-}]}), shows that for the value of y = 0.6 (material β-In2S3) the refraction index is higher than that of the thin layer obtained for the value of y = 0.75 (material In6S7) [1], and that the extinction coefficient is lower than that of In6S7. For In-S thin layers, α is also high with values varing between 2×10^4 and 12×10^4 cm^{-1}. The direct band gap of materials β-In2S3 and In6S7 are 2.22 eV and 1.94 eV respectively. The heat treatment under vacuum at 573 K during two hours improves the optical quality of the thin " p " type CuInS2 Layer. Dans ce travail nous avons étudié les propriétés optiques des couches minces de CuInS2 et d'In-S réalisées par pulvérisation chimique réactive sans air " P.S.A. ". L'étude des propriétés optiques des couches minces de CuInS2, à partir des mesures ellipsométriques effectuées dans le domaine des photons incidents [1,5-4] eV, a révélé que l'indice de réfraction n_1 et le coefficient d'extinction k_1 varient respectivement dans les domaines [1,8-2,3] et [0,45-0,80]. Le coefficient d'absorption α, des couches minces de CuInS2 r

  2. 2D Modelling of the Gorkha earthquake through the joint exploitation of Sentinel 1-A DInSAR measurements and geological, structural and seismological information

    NASA Astrophysics Data System (ADS)

    De Novellis, Vincenzo; Castaldo, Raffaele; Solaro, Giuseppe; De Luca, Claudio; Pepe, Susi; Bonano, Manuela; Casu, Francesco; Zinno, Ivana; Manunta, Michele; Lanari, Riccardo; Tizzani, Pietro

    2016-04-01

    A Mw 7.8 earthquake struck Nepal on 25 April 2015 at 06:11:26 UTC, killing more than 9,000 people, injuring more than 23,000 and producing extensive damages. The main seismic event, known as the Gorkha earthquake, had its epicenter localized at ~82 km NW of the Kathmandu city and the hypocenter at a depth of approximately 15 km. After the main shock event, about 100 aftershocks occurred during the following months, propagating toward the south-east direction; in particular, the most energetic shocks were the Mw 6.7 and Mw 7.3 occurred on 26 April and 12 May, respectively. In this study, we model the causative fault of the earthquake by jointly exploiting surface deformation retrieved by the DInSAR measurements collected through the Sentinel 1-A (S1A) space-borne sensor and the available geological, structural and seismological information. We first exploit the analytical solution performing a back-analysis of the ground deformation detected by the first co-seismic S1A interferogram, computed by exploiting the 17/04/2015 and 29/04/2015 SAR acquisitions and encompassing the main earthquake and some aftershocks, to search for the location and geometry of the fault plane. Starting from these findings and by benefiting from the available geological, structural and seismological data, we carry out a Finite Element (FE)-based 2D modelling of the causative fault, in order to evaluate the impact of the geological structures activated during the seismic event on the distribution of the ground deformation field. The obtained results show that the causative fault has a rather complex compressive structure, dipping northward, formed by segments with different dip angles: 6° the deep segment and 60° the shallower one. Therefore, although the hypocenters of the main shock and most of the more energetic aftershocks are located along the deeper plane, corresponding to a segment of the Main Himalayan Thrust (MHT), the FE solution also indicates the contribution of the shallower

  3. Investigating a damaging buried sinkhole cluster in an urban area (Zaragoza city, NE Spain) integrating multiple techniques: Geomorphological surveys, DInSAR, DEMs, GPR, ERT, and trenching

    NASA Astrophysics Data System (ADS)

    Carbonel, Domingo; Rodríguez-Tribaldos, Verónica; Gutiérrez, Francisco; Galve, Jorge Pedro; Guerrero, Jesús; Zarroca, Mario; Roqué, Carles; Linares, Rogelio; McCalpin, James P.; Acosta, Enrique

    2015-01-01

    This contribution analyses a complex sinkhole cluster buried by urban elements in the mantled evaporite karst of Zaragoza city, NE Spain, where active subsidence has caused significant economic losses (~ 0.3 million Euro). The investigation, conducted after the development of the area, has involved the application of multiple surface and subsurface techniques. A detailed map of modern surface deformation indicates two active coalescing sinkholes, whereas the interpretation of old aerial photographs reveals the presence of two additional dormant sinkholes beneath human structures that might reactivate in the near future. DInSAR (Differential Interferometry Synthetic Aperture Radar) displacement data have limited spatial coverage mainly due to high subsidence rates and surface changes (re-pavement), and the Electrical Resistivity Tomography (ERT) and trenching investigations were severely restricted by the presence of urban elements. Nonetheless, the three techniques consistently indicate that the area affected by subsidence is larger than that defined by surface deformation features. The performance of the Ground Penetrating Radar (GPR) technique was adversely affected by the presence of highly conductive and massive anthropogenic deposits, but some profiles reveal that subsidence in the central sector of one of the sinkholes is mainly accommodated by sagging. The stratigraphic and structural relationships observed in a trench dug across the topographic margin of one of the sinkholes may be alternatively interpreted by three collapse events of around 0.6 m that occurred after 290 yr BP, or by progressive fault displacement combined with episodic anthropogenic excavation and fill. Average subsidence rates of > 6.6 mm/yr and 40 mm/yr have been calculated using stratigraphic markers dated by the radiocarbon method and historical information, respectively. This case study illustrates the need of conducting thorough investigations in sinkhole areas during the pre

  4. [Quality management in a combined clinic - the quality management system according to DIN EN ISO 9001 of the The German Association of Spa Accommodation Resorts e. V. (VdKB)].

    PubMed

    Eckert, H; Schulze, U

    2004-06-01

    The implementation of a quality system in health care organizations offers huge potentials for improvement and development. But the realization of such systems necessitates high investments, which small companies and family businesses often are unable to raise. The German Association of Spa Accommodation Resorts (VdKB) commissioned two consultants to develop a reasonably priced implementation concept of a DIN EN ISO 9001 quality system specially adjusted to small companies and family businesses in medical spa and rehabilitation services, which was successfully accredited in May 2003. This paper describes fundamental requirements in combine management systems, considers the pros and cons of management combines and demonstrates the practical realization of combine requirements on the example of the VdKB-combine system.

  5. Spatio-temporal evolution of anthropogenic deformation around Cerro Prieto geothermal field in the Mexicali Valley, B.C., Mexico, between 1993 and 2009 from DInSAR and leveling.

    NASA Astrophysics Data System (ADS)

    Sarychikhina, Olga; Glowacka, Ewa; Robles, Braulio; Mojarro, Jose

    2014-05-01

    Land subsidence is an environmental hazard which could be caused by withdrawal of large amounts of fluid from beneath the earth's surface. Land subsidence is an issue in several geothermal fields worldwide (e.g., Geysers, USA (Mossop and Segall, 1997), Wairakei-Tauhara, New Zealand (Allis et al., 2009)). Cerro Prieto geothermal field (CPGF), located in the Mexicali Valley, northwest Mexico, is the oldest and largest Mexican geothermal field in operation and has been producing electricity since 1973. The large amount of geothermal fluids extracted to supply steam to the power plants has resulted in considerable deformation in and around the field (e.g. Glowacka et al., 1996, 1999; Carnec and Fabriol, 1999; Sarychikhina et al., 2011). The deformation includes land subsidence and related ground fissuring and faulting. These phenomena have produced severe damages to the local infrastructure such as roads, irrigation canals and other facilities. Detection of land subsidence and monitoring of the spatial and temporal changes of its pattern and magnitude can provide important information about the dynamics of this process and controlling geological structures. The technique of Differential Synthetic Aperture Radar Interferometry (DInSAR) has been demonstrated to be a very effective technique for measuring ground deformation. This study presents an application of DInSAR interferogram stacking technique to investigate the land subsidence in the Mexicali Valley near CPGF. C-band ENVISAR ASAR images acquired between 2003 and 2009 from the ascending (track 306, frame 639) and descending track (track 84, frame 2961), obtained from the European Space Agency (ESA), as part of ESA CAT-1 project (ID - C1P3508), were used. Gamma ISP and DIFF/GEO software packages were used to calculate differential interferograms from SLC data and for differential interferograms stacking (Wegmüller and Werner, 1997). Eight average annual deformation rate maps were generated for 2005 (descending

  6. Construção de um catálogo de aglomerados abertos para estudo da dinâmica da estrutura espiral da Galáxia

    NASA Astrophysics Data System (ADS)

    Carlos, I. M.; Lépine, J. R. D.

    2003-08-01

    Os aglomerados abertos são objetos de grande valor para o estudo da dinâmica da Galáxia devido esses objetos terem uma faixa de idade relativamente ampla. O trabalho visa estudar a dinâmica da estrutura espiral da Galáxia principalmente através do uso desses aglomerados, uma vez que o estudo da cinemática desses objetos é fundamental para esse objetivo. Nosso grupo trabalha no sentido de construir uma base de dados de aglomerados abertos contendo coordenadas, distância, idade, movimentos próprios e velocidades radiais e já disponibiliza uma nova versão do catálogo de aglomerados abertos o qual é uma compilação de edições anteriores, principalmente Lynga (1987), Mermilliod (1995) e ESO-B (Lauberts 1982). Nossa amostra possui cerca de 1630 aglomerados, mas nem todos os parâmetros acima citados foram determinados em sua totalidade. Para determinarmos esses parâmetros, derivamos as cores intrínsecas das estrelas membro de cada aglomerado a partir de seus tipos espectrais (busca feita no SIMBAD) obtendo assim o excesso de cor individual. A distribuição dos excessos de cor foi então utilizada para derivarmos o avermelhamento médio para cada aglomerado. De maneira similar, os tipos espectrais foram usados para estimar as magnitudes absolutas, e com as magnitudes absolutas e aparentes determinamos a respectiva distribuição do módulo de distância e finalmente a distância. Para determinar as idades foram confeccionados os diagramas cor-magnitude das estrelas de cada aglomerado onde foram superpostas a Seqüência Principal de Idade Zero (ZAMS). Superpomos a ZAMS de Schmidt-Kaler e isócronas de composição solar. Essas isócronas foram usadas para determinação das idades dos aglomerados. Uma vez que não temos ainda resultados finais, apresentamos então alguns diagramas cor-magnitude os quais foram usados para determinação, principalmente, da distância e idade dos aglomerados.

  7. (1)H, (13)C, and (15)N backbone resonance assignments of the full-length 40 kDa S. acidocaldarius Y-family DNA polymerase, dinB homolog.

    PubMed

    Moro, Sean L; Cocco, Melanie J

    2015-10-01

    The dinB homolog (Dbh) is a member of the Y-family of translesion DNA polymerases, which are specialized to accurately replicate DNA across from a wide variety of lesions in living cells. Lesioned bases block the progression of high-fidelity polymerases and cause detrimental replication fork stalling; Y-family polymerases can bypass these lesions. The active site of the translesion synthesis polymerase is more open than that of a replicative polymerase; consequently Dbh polymerizes with low fidelity. Bypass polymerases also have low processivity. Short extension past the lesion allows the high-fidelity polymerase to switch back onto the site of replication. Dbh and the other Y-family polymerases have been used as structural models to investigate the mechanisms of DNA polymerization and lesion bypass. Many high-resolution crystal structures of Y-family polymerases have been reported. NMR dynamics studies can complement these structures by providing a measure of protein motions. Here we report the (15)N, (1)H, and (13)C backbone resonance assignments at two temperatures (35 and 50 °C) for Sulfolobus acidocaldarius Dbh polymerase. Backbone resonance assignments have been obtained for 86 % of the residues. The polymerase active site is assigned as well as the majority of residues in each of the four domains. PMID:26154586

  8. Dinámica de pulsares jóvenes

    NASA Astrophysics Data System (ADS)

    Allen, M. P.; Horvath, J. E.

    La observación detallada de los pulsos en varios pulsares jóvenes (τ < 105 yr) permitió detectar varios aumentos en la frecuencia de emisión gliches con cambios permanentes en Δ {˙ Ω} / {˙ Ω}. A través de las ecuaciones de movimiento se investiga, utilizando parametrizaciones simples, la hipótesis de que el ángulo entre Ω y el dipolo magnético M sea responsable de ese comportamiento. Se derivan curvas analíticas para la evolución de Ω (t) y se estudia la posibilidad de describir un conjunto de observables (incluyendo el braking index n) con estos modelos.

  9. Nuevas herramientas en dinámica de actitud.

    NASA Astrophysics Data System (ADS)

    Arribas, M.; Elipe, A.

    In the software market, a number of applications designed for symbolic computations and running on desk computers are continously appearing. Among them the authors use Mathematica to handle the very discouraging expressions appearing in the attitude dynamics problem. The graphic capability of Mathematica is used in the qualitative analysis of the attitude of an artificial satellite, in order to locate where the possible bifurcations take place.

  10. Determining the role of hydrologic variability on DIN export from the Catskill Mountains

    EPA Science Inventory

    The Catskill region of New York State receives some of the highest rates of atmospheric nitrogen deposition in the northeastern US (approximately 6.2 kg ha-1 yr-1), and headwater streams have elevated nitrate concentrations (mean of stream surveys = 0.27 – 0.35 mg N l-1). Althou...

  11. Sediment DIN fluxes and preferential recycling of benthic microalgal nitrogen in a shallow macrotidal estuary

    USGS Publications Warehouse

    Tobias, C.; Giblin, A.; McClelland, J.; Tucker, J.; Peterson, B.

    2003-01-01

    Sediment-water fluxes of NH4+, NO3-, dissolved inorganic carbon, and O2 were measured in cores collected from the upper Rowley River estuary, Massachusetts, and used to calculate rates of organic nitrogen (N) mineralization, nitrification, and coupled and direct denitrification (DNF). The cores contained 15N label in benthic microalgae (BMA) and in NO3- in the overlying water as a result of an ongoing whole-estuary 15NO 3- enrichment study (NISOTREX II). The tracer allowed for estimation of gross NO3- regeneration in sediments and the contribution of BMA derived N to total mineralization. The mean mineralization rate between sites was 16.0 ?? 2.0 mmol N m-2 d-1. Approximately 13 to 56% of the mineralized N was nitrified at rates ranging from 1.8 to 10.1 mmol N m-2 d-1. Total denitrification was dominated by direct DNF (3.6 mmol N m-2 d -1) furthest upstream, where NO3- concentrations were highest. Coupled DNF was most important (8.0 mmol N m -2 d-1) in the sediments with high nitrification and low water column NO3-. A gross NO3- flux from sediments to water of 0.9 to 2.1 mmol N m-2 d-1 was estimated from the isotope dilution of ??15NO 3- in the overlying water of the cores. The isotope dilution seen in the cores was also detected as a deviation from conservative ??15NO3- mixing along estuarine transects. Incorporation of this NO3- regeneration into the DNF calculations effectively increased the estimate of direct DNF by up to 50% and decreased the coupled DNF estimate by up to 220%. Increasing ?? 15NH4+ in the water of the cores indicated that the 15N-labelled BMA were preferentially mineralized over bulk sediment organic N. Additional 15N enrichments in the sediment bacterial biomarker diaminopimelic acid showed a link among 15N-labeled BMA, active bacteria, and 15NH 4+released to the overlying water. Based on ?? 15NH4+ enrichments in the cores, BMA accounted for approximately 50 to 100% of the N mineralized. An isotopic enrichment of ??15NH4+ above background in the estuary was observed at a magnitude consistent with the core-based rates of BMA mineralization. These results provide further evidence that BMA are not unidirectional sinks for water column-dissolved organic nitrogen, but instead act to turn over N between sediments and estuarine water on the scale of days.

  12. Efectos dinámicos de las resonancias orbitales en el Sistema Solar

    NASA Astrophysics Data System (ADS)

    Gallardo, T.

    2016-08-01

    We describe the different orbital resonances in the Solar System that primarily affect minor bodies and some satellites. We present an idea of how to study the two body and three body mean motion resonances, secular resonances and Kozai-Lidov mechanism and the conclusions that can be drawn from these studies. Weak resonances generate subtle periodic orbital variations and produce temporary concentrations of objects while strong resonances can generate large variations in eccentricity and inclination risking the orbital stability.

  13. The DinJ/RelE toxin-antitoxin system suppresses virulence in Xylella fastidiosa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Xylella fastidiosa, the causal agent of a number agriculturally important plant diseases, encodes multiple toxin-antitoxin (TA) systems. TA modules consist of a toxin protein co-expressed with a specific antitoxin, and are often acquired through horizontal gene transfer. Antitoxin molecules (RNA or ...

  14. [Certification according to DIN EN ISO 9001 in MDK in Hessia--a report of experiences].

    PubMed

    Hübner, M; Andersen, J; von Mittelstaedt, G

    2000-02-01

    Quality assurance is a routine and indispensable part of the work of the Medizinische Dienst der Krankenversicherung (MDK) (Medical Services of statutory health insurance bodies in Germany). To optimize the internal organisational processes, a quality assurance system (QAS), certified by EQ Zert, Ulm (an accredited certifier of the TGA), was implemented for the first time in one of the departments of the MDK, namely, the hospital department. Employees and management consider the advantages to be as follows: the aims of the department are clearly described. the processes are now self-evident and more strictly observed, overlaps to other fields of the company are defined. Both an Error Management System with follow up measures, and a Project Management System to control projects have been implemented. The documentation system was standardized, and consequently relocating documents has become more streamlined. An MDK self-evaluation was performed as part of an internal audit. The audit showed that the QAS of the hospital department of the MDK in Hesse is indeed highly developed. It is anticipated that gradually other fields of the MDK will also be certified, to comply with the changing requirements.

  15. Muffled by the Din: The Competitive Noneffects of the Cleveland Voucher Program.

    ERIC Educational Resources Information Center

    Hess, Frederick M.; McGuinn, Patrick J.

    2002-01-01

    Examines how the introduction of the Cleveland voucher experiment in 1995 affected the administration and leadership of Cleveland's public schools. As of summer 2001, the program has produced virtually no visible effects. Results suggest that choice-based reform may not spur improvement in urban school systems, at least in the short term or when…

  16. The last days of Sala al-Din (Saladin) "noble enemy" of the third Crusade.

    PubMed

    Mackowiak, Philip A

    2010-10-01

    Saladin, "noble enemy" of Richard the Lionheart and victor at the battle of Hattin, died suddenly in 1193 A.D. at the age of 56. The clinical information preserved in the historical record is insufficient to render a definitive diagnosis for Saladin's final illness, and yet, it contains enough details to narrow the list of possibilities to just a few and also to critique his treatment in light of the medical concepts of his day.

  17. Estudio de eventos dinámicos en ondas milimétricas

    NASA Astrophysics Data System (ADS)

    Cristiani, G.; Martínez, G.; Raulin, J. P.; Giménez de Castro, G.; Rovira, M.

    El estudio de la actividad solar con el telescopio para ondas submilimétricas (SST), nos permite, por vez primera, trabajar con una resolución temporal de milisegundos. Este hecho ha permitido observar emisión nunca antes comprobada, pulsos o flashes extremadamente rápidos provenientes de las regiones activas, los cuales parecen preanunciar fulguraciones en dichas regiones. Se muestra, como ejemplo, una fulguración observada con el telescopio HASTA en Hα, y los pulsos rápidos que la preceden observados con el SST. Para cuantificar la influencia de la atmósfera terrestre en los datos registrados, se está estudiando la variabilidad temporal de las opacidades a las frecuecias de trabajo (212 y 405 Ghz), es decir los rangos de tiempo para los cuales la opacidad puede variar apreciablemente. Con este fin se calcula la eficiencia de cada canal multiplicada por la temperatura del Sol a estas frecuencias (estas son conocidas con una incerteza del 20 %). Se muestran los resultados obtenidos para cada canal, en donde se grafica este producto como función de la opacidad.

  18. Dinámica de cúmulos estelares en la Nube Menor de Magallanes

    NASA Astrophysics Data System (ADS)

    Mondino-Llermanos, A. E.; Piatti, A. E.; Carpintero, D. D.

    2016-08-01

    The dynamical evolution of star clusters in the Small Magellanic Cloud is nowadays a conundrum which deserves particular attention. In this work, we address such an issue by performing numerical simulations of their orbital motions. In order to do that, we adopted a gravitational potential for the galaxy and the presently known spatial-age-metallicity distribution, and attained their birthplaces by computing their orbital motions backwards for an interval equals to their ages. We aim at investigating the impact on the metal abundance spatial distribution by considering their original positions instead of the present ones.

  19. Evidence for a non-opioid sigma binding site din the guinea-pig myenteric plexus

    SciTech Connect

    Roman, F.; Pascaud, X.; Vauche, D.; Junien, J.

    1988-01-01

    The presence of a binding site to (+)-(/sup 3/H)SKF 10,047 was demonstrated in a guinea-pig myenteric plexus (MYP) membrane preparation. Specific binding to this receptor was saturable, reversible, linear with protein concentration and consisted of two components, a high affinity site and a low affinity site. Morphine and naloxone 10/sup -4/M were unable to displace (+)-(/sup 3/H)SKF 10,047 binding. Haloperidol, imipramine, ethylketocyclazocine and propranolol were among the most potent compounds to inhibit this specific binding. These results suggest the presence of a non-opioid haloperidol sensitive sigma receptor in the MYP of the guinea-pig.

  20. 77 FR 18752 - Benzidine-Based Chemical Substances; Di-n

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-28

    ... uses ``any use other than as a reagent to test for hydrogen peroxide in milk; a reagent to test for hydrogen sulfate, hydrogen cyanide, and nicotine; a stain in microscopy; a reagent for detecting blood; an... peroxide in milk; a reagent to test for hydrogen sulfate, hydrogen cyanide, and nicotine; a stain...

  1. Evaporación dinámica del cinturón de asteroides original

    NASA Astrophysics Data System (ADS)

    Brunini, A.

    Hemos integrado numéricamente un enjambre de 3000 partículas en la región del cinturón de asteroides, sujetas a las perturbaciones gravitatorias de Júpiter y Saturno. Al cabo de 107 años, se han formado ya todos los gaps de Kirkwood observados en el cinturón actual. El grupo en la resonancia 3/2 es, aunque en menor grado, también visible. Los tiempos de Lyapunov computados para los asteroides sobrevivientes, nos ha permitido encontrar la fracción de ellos que es capaz de sobrevivir por toda la edad del sistema solar, merced a la aplicacion de la relación empírica que vincula dichos tiempos al tiempo en el cual se manifiestan grandes transiciones orbitales. La fracción de supervivientes es de aproximadamente 1/100. El resto de la masa faltante en el cinturón, es atribuible a colisiones catastróficas con cometas en etapas primordiales.

  2. Comportamiento dinámico de asteroides en la resonancia 2:1

    NASA Astrophysics Data System (ADS)

    López García, F.; Brunini, A.

    El propósito de este trabajo es mostrar los resultados obtenidos del estudio del movimiento de asteroides cercanos a la conmensurabilidad 2:1 con el movimiento medio de Júpiter, analizando el comportamiento de órbitas de asteroides reales y ficticios. Se analizan los tiempos de Lyapunov obtenidos a partir de la integración de las ecuaciones del movimiento. Se han estudiado la órbitas utilizando el modelo de cinco cuerpos y se han considerado los casos planar y espacial. Las simulaciones numéricas se realizaron utilizando integradores simpléticos y el intervalo de tiempo de integración fue de T = 107 años.

  3. Dinámica de objetos artificiales alrededor de la Tierra

    NASA Astrophysics Data System (ADS)

    Schulz, W.

    Nowadays, space equipments are designed to withstand the space environ- ment and ensure their missions until the end of the expected useful life of the satellite. However, if not removed from nominal orbits at the end of activities, satellites can be very risky to other space objects for long peri- ods of time. By several reasons, a single spacecraft can turn into a lot of small objects that are potentially dangerous for operational missions around them. Due to a natural mechanism, these space debris tend to reenter into Earth's atmosphere in a period of time that varies according to their physical and orbital characteristics. The reentry of space objects is common and can lead to fragmentation under the effects of thermal and mechanical stresses some kilometers above the Earth's surface. In this paper, some results of a space debris monitoring performed in Argentina for academic purposes are presented. The goal is to forecast natural reentry objects for the next 7 days. FULL TEXT IN SPANISH

  4. Nasir al-Din al-Tusi's Memoir on Astronomy (al-Tadhkira fi cilm al-hay'a)

    NASA Astrophysics Data System (ADS)

    Ragep, F. J.

    Tusi (1201-1274 a.d.) was an Arabic scholar whose writings became the standard texts in several disciplines for several centuries. They include editions of Euclid's Elements and Ptolemy's Almagest, as well as other books on mathematics and astronomy, and books on logic, ethics, religion. He wrote the Tadhkira, to be "a summary account of `astronomy' presented in narrative form. The details are expounded and proofs of the validity are furnished in the Almagest. Indeed, ours would not be a complete science if taken in isolation from the Almagest for it is a report of what is established therein." It is thus not only a sort of running commentary on the Almagest, but also an account of medieval Arabic cosmology. Jamil Ragep has not only translated the text of the Tadhkira, but has also provided a lengthy introduction with a biography of Tusi and a discussion of the context in which the Tadhkira was written and its influence, as well as a detailed and thorough commentary on each section of the text.

  5. Comportamiento dinámico de la resonancia 4:1 en el cinturón principal de asteroides

    NASA Astrophysics Data System (ADS)

    López García, F.; Brunini, A.

    We have studied the dynamics of mean motion resonance with Jupiter in the 4:1 gap using gravitational methods only. This mechanism is capable of explaining in a uniform way this Kirkwood gap. Our work is based on the numerical integration of the full differential equations of motion in the framework of the restricted five-body problem using symplectic integrators. The variation of the orbital elements on a time span of 5x107 yr is shown. Moreover we have studied the additional effects such as the secular resonances and the diagram in the (a,e) plane with the Jacobi's integral (elliptic problem). The numerical results show that most of the trajectories of fictitious asteroids studied reach, after a few millon of years, the 3:1 gap and others are temporarily captured by Mars and some become Earth crossers. This gap may be explained considering eccentricities and inclinations (e < 0.1, i < 2o.5 ). Besides, we present the behaviour of Lyapunov exponents and the renormalization time.

  6. Preliminary results of ESA Category-1 Project 5834 "Application of DInSAR technique to areas of active ground deformations"

    NASA Astrophysics Data System (ADS)

    Massa, B.; D'Auria, L.

    2009-04-01

    We have established a processing chain of Synthetic Aperture Radar (SAR) data for identification and parametrisation of deformation sources in areas of active ground deformation (e.g. seismogenic areas, volcanic districts). SAR data from European Space Agency (ESA) satellites ERS-2 and ENVISAT are used. SAR and InSAR data processing LEVEL 0 SAR data are focussed to Single Look Complex (SLC) through ROI_PAC (Copyright 2002-2008, Caltech/Jet Propulsion Laboratory). We perform an advanced data processing using Doris (Kampes and Usai, 1999) a single program that can do most common steps of the interferometric radar processing starting from SLC data to generation of interferometric products and geocoding. Unwrapping of interferometric phase is performed using the public domain software snaphu (Chen and Zebker, 2001). Modeling of deformation sources We propose a novel inversion approach base on non-linear inversion. The forward modeling is provided by the semi-analytic deformation model for point sources and finite faults. The parameters of the fault (center position, width, height, rake and seismic moment) are inverted using a combination of non-linear optimization algorithms (as Monte-Carlo, Nelder&Mead Simplex and Simulated Annealing). The misfit function defined for the optimization is based on the L2 norm of the error weighted by the coherence of the considered spatial point. Test datasets To test our modeling procedure we chose three different study areas, refer to mainly strike-slip seismogenic sources with different orientation to respect satellite Line Of Sight (LOS): December 26 2003 Iranian earthquake (Bam e.), data from both ascending and descending passes of ENVISAT ASAR narrow swath IS2 (RAW and SLCs); August 17 1999 Turkey earthquake (Izmit e.), data from both ascending and descending passes of ERS-2 AMI SAR (SLCs); June 17-21 2000 Iceland earthquakes, data from both ascending and descending passes of ERS-2 AMI SAR (SLCs). Tests carried over real deformation unwrapped interferograms have shown encouraging results. Preliminary modeling of deformation sources is presented. Acknowledgements Data provided by the European Space Agency (ESA CAT-1 Project 5834, P.I. B. Massa). References Chen W., H. Zebker A. (2001) -Two-dimensional phase unwrapping with use of statistical models for cost functions in nonlinear optimization- Journal of the Optical Society of America, 18, 338-351. Kampes B., Usai S. (1999) -Doris: The Delft object-oriented Radar Interferometric software.- In: proceedings ITC 2nd ORS symposium, August 1999 (CD-ROM).

  7. Fricción dinámica: Influencia de órbitas caóticas

    NASA Astrophysics Data System (ADS)

    Cora, S. A.; Vergne, M. M.; Muzzio, J. C.

    We have used numerical experiments to investigate the orbital decay, caused by dynamical friction, of a rigid satellite which moves within a larger stellar system (a galaxy), whose potential is non-integrable. This type of potential has regular and irregular orbits, being the last ones chaotic respect of having exponential sensitivity to perturbations, a feature that makes them to relax in a time much shorter than regular ones. Assuming that the dynamical friction is inversely proportional to the relaxation time, this phenomenon would increase in the presence of chaotic orbits (Pfenniger 1986). Therefore, we present preliminary numerical results to check this idea. We considered two different triaxial galaxy models with different percentage of chaotic orbits. 1) The triaxial generalization of spherical models of Dehnen (1993), with a constant-density core, where the orbits can be identified with one of the four families of regular orbits in Stackel potentials (boxes and the three families of tubes). When a central compact object (black hole) is included a porcentage of the boxlike orbits are rendered chaotic. 2) The modified Satoh galaxy model (Satoh 1980) without rotation, in which the orbits are mostly regular (boxes and tubes). However, if we consider the triaxial galaxy with rotation the resulting potential is non-integrable with a high degree of chaos. The satellite is modelled by a softened point mass, moving on a circular orbit in the spherical model. To integrate he equation of motion a non-self-consistent code is used. The results of a few simulations suggest that the presence of chaotic orbits does not affect significantly the orbital decay of the satellite.

  8. On efeito do achatamento nos pontos de equilíbrio e na dinâmica de sistemas coorbitais

    NASA Astrophysics Data System (ADS)

    Mourão, D. C.; Winter, O. C.; Yokoyama, T.

    2003-08-01

    Neste trabalho analisamos o efeito do achatamento do corpo principal nos pontos de equilíbrio lagrangianos e na configuração de órbitas girino-ferradura. Enfatizamos os sistemas coorbitais de satélites de Saturno, pois se encontram em relativa proximidade com o planeta, em que o efeito do achatamento se torna mais evidente. O estudo é dividido em três etapas independentes. Na primeira fase analisamos as equações de movimento do problema restrito de três corpos considerando o efeito do achatamento, e através do balanceamento de forças buscamos a nova configuração dos pontos de equilíbrio lagrangianos. Concluímos, nesta etapa, que os pontos de equilíbrio estáveis apresentam um pequeno deslocamento definido pelo parâmetro de achatamento, não podendo ser mais representados por triângulos eqüiláteros. Aplicamos este resultado aos satélites coorbitais de Tetis e Dione, encontrando as posições de equilíbrio levemente deslocadas em relação ao caso sem achatamento. Na segunda fase visamos o sistema Saturno-Jano-Epimeteu, que por se tratar de um sistema de massas comparáveis, optamos por desenvolver as equações de Yoder et al (Icarus 53, pág 431-443, 1983), que permitem determinar os pontos de equilíbrio e a amplitude de oscilação angular das órbitas girino-ferradura para o problema não-restrito de três corpos, porém, no nosso estudo consideramos o efeito do achatamento do corpo principal nestas equações. Encontramos que a distância angular entre satélites, quando em posição de equilíbrio estável, diminui quanto maior for o parâmetro de achatamento do corpo principal. Além disso, a órbita de transição girino-ferradura possui largura angular menor em relação ao caso sem achatamento. Por fim, realizamos integrações numéricas para os casos reais de coorbitais de Saturno comparando com os resultados analíticos. Nestas integrações simulamos diversas órbitas girino-ferradura com diferentes parâmetros de achatamento, utilizando condições iniciais corrigidas para a presença do achatamento.

  9. Protective effects of resveratrol against di-n buthyl phthalate induced toxicity in ductus epididymis and ductus deferens in rats

    PubMed Central

    Sahin, Erhan; Ilgaz, Celal; Erdoğan, Deniz; Take, Gülnur; Göktas, Güleser

    2014-01-01

    Objective: This study aimed to observe the possible protective effects of resveratrol (RSV) against damage induced by di-n-butylphthalate (DBP), on the ductus epididymis and deferens in rats. Materials and Methods: Six groups of rats were used in the experiment: Group 1: Control group; Group 2: Solvent (carboxymethylcellulose (CMC), 10ml/kg); Group 3: 500 mg/kg/day DBP; Group 4: 500 mg/kg/day DBP+20 mg/kg/day RSV; Group 5: 1000 mg/kg/day DBP; Group 6: 1000mg/kg/day DBP + 20 mg/kg/day RSV. Groups were treated by gavage for 30 days. Immunohistochemical, electronmicroscopic and histomorphometric examinations were carried out in the epididymis and deferens. Results: In the ductus epididymis and deferens mitochondrial crystolysis, exfoliation of the stereocilia and openings in lateral surface increased with DBP dosage, but these structures were recovered with RSV. DBP reduced the epithelial height of epididymis and vas deferens. Lumen dilatation was observed in both tissues. These disorders may lead to dysfunction of epithelial absorption. In the TUNEL examinations in both tissues, there were no apoptotic cells or apoptotic bodies. Conclusion: In conclusion, DBP administration caused structural degeneration in the epididymis and deferens, parallel to dose evaluation and RSV can reverse these changes with its protective effects. PMID:24550585

  10. Pump testing strategies and associated tribological considerations -- Vane pump testing methods ASTM D 2882, IP281, and DIN 51389

    SciTech Connect

    Reichel, J.

    1997-12-31

    Various test methods have been developed to determine the performance limits of various classes of hydraulic fluids. Lubrication capacity depends on various fundamental fluid parameters including viscosity and anti-wear properties. Critical elements of hydraulic pump and motor lubrication, which is characterized by sliding line-contact wear, will be discussed here. In vane pumps, the pressure loaded tips of the vanes are under Hertz-type load in contact with the surface of the cam ring, and rotate at a high speed creating a sliding line-contact. Due to this sliding line contact, the vane pump is the best-suited instrument for determination of the anti-wear performance of hydraulic fluids within acceptable time and at reasonable expense. Alternatively, hydraulic pump and motor testing may require greater energy, 150 kW or more over a period of more than 1,000 hours significantly increasing the cost of testing. Furthermore, tests on smaller versions of one type of pump or motor do not necessarily correlate with larger units of similar design. Therefore, it would be desirable to develop a laboratory test that: utilizes a rig with standard wear parts, provides a selective method for identifying various forms of lubricant failure, and that permits tests correlation with a wide variety of hydraulic pumps and motors used in the industry today.

  11. Linear and Non-Linear Long-Term Terrain Deformation with DInSAR (CPT: Coherent Pixels Technique)

    NASA Astrophysics Data System (ADS)

    Mallorqui, J. J.; Mora, O.; Blanco, P.; Broquetas, A.

    2004-06-01

    / In this paper, an advanced technique for the generation of deformation maps using SAR (Synthetic Aperture Radar) data is presented. The algorithm, called the Coherent Pixels Technique, estimates the linear and non-linear components of the displacement, the error of the Digital Elevation Model (DEM) used to cancel the topographic terms, and the atmospheric artifacts from a reduced set of low spatial resolution interferograms. The pixel candidates are selected from those presenting a good coherence level in the whole set of interferograms and the resulting non-uniform mesh tessellated with the Delauney triangulation to establish connections among them. The linear component of movement and DEM error are estimated adjusting a linear model to the data only on the connections. Later on, this information, once integrated to retrieve the absolute values, is used to calculate the non-linear component of movement and atmospheric artifacts with alternate filtering techniques in both temporal and spatial domains. The method presents high flexibility with respect to the required number of images and the baselines length. However, better results are obtained with large datasets of short baseline interferograms. The technique has been tested with ERS SAR data from an area of Catalonia (Spain) and the Campi Flegrei area (Naples, Italy) and validated with on-field precise levelling measurements.

  12. Extracting a Whisper from the DIN: A Bayesian-Inductive Approach to Learning an Anticipatory Model of Cavitation

    SciTech Connect

    Kercel, S.W.

    1999-11-07

    For several reasons, Bayesian parameter estimation is superior to other methods for inductively learning a model for an anticipatory system. Since it exploits prior knowledge, the analysis begins from a more advantageous starting point than other methods. Also, since "nuisance parameters" can be removed from the Bayesian analysis, the description of the model need not be as complete as is necessary for such methods as matched filtering. In the limit of perfectly random noise and a perfect description of the model, the signal-to-noise ratio improves as the square root of the number of samples in the data. Even with the imperfections of real-world data, Bayesian methods approach this ideal limit of performance more closely than other methods. These capabilities provide a strategy for addressing a major unsolved problem in pump operation: the identification of precursors of cavitation. Cavitation causes immediate degradation of pump performance and ultimate destruction of the pump. However, the most efficient point to operate a pump is just below the threshold of cavitation. It might be hoped that a straightforward method to minimize pump cavitation damage would be to simply adjust the operating point until the inception of cavitation is detected and then to slightly readjust the operating point to let the cavitation vanish. However, due to the continuously evolving state of the fluid moving through the pump, the threshold of cavitation tends to wander. What is needed is to anticipate cavitation, and this requires the detection and identification of precursor features that occur just before cavitation starts.

  13. Avoiding a Din at Dinner or, Teaching Students to Argue for Themselves: Year 13 Plan a Historians' Dinner Party

    ERIC Educational Resources Information Center

    Richards, Keeley

    2012-01-01

    Keeley Richards secured a fundamental shift in some of her Year 13 students' ability to argue. She did it by getting them to engage more fully with the practice of argument itself, as enacted by four historians. At the centre of her lesson sequence was an original activity: the historians' dinner party. Richards uses this activity to point to…

  14. Les complexes alcalins sous-saturés à carbonatites de la région d'In Imanal (Sahara malien): une présentation

    NASA Astrophysics Data System (ADS)

    Sauvage, J.-F.; Savard, R.

    During the exploration program of the United Nations Revolving Fund for Natural Resources Exploration on the eastern margin of the west African craton, a new carbonatitic assemblage has been discovered and studied. This assemblage belongs to an alkaline undersaturated province where annular complexes are roughly disposed in a north-south trend probably along a permian age graben. Four complexes in which carbonatites can be observed are described in this paper; Niobium and Rare Earth mineralization is related to carbonatitic intrusions. In west Africa, mineralization of this type is only reported in the carbonatites of Tamazert (Morocco) and those of the In Imanal area (Mali).

  15. Effects of ambient DIN:DIP ratio on the nitrogen uptake of harmful dinoflagellate Prorocentrum minimum and Prorocentrum donghaiense in turbidistat

    NASA Astrophysics Data System (ADS)

    Li, Ji; Glibert, Patricia M.; Alexander, Jeffrey A.

    2011-07-01

    The effects of varying nitrogen (N): phosphorus (P) ratios on the growth and N-uptake and assimilation of the harmful dinoflagellates Prorocentrum minimum and Prorocentrum donghaiense were examined in turbidistat culture experiments. Algal cultures were supplied with media containing PO{4/3-} in various concentrations to obtain a wide range of N:P ratios. Experiments to determine rates of N uptake and assimilation of different N sources (NO{3/-}, NH{4/+}, urea and glycine by P. minimum and NO{3/-}, NH{4/+} by P. donghaiense) were conducted using 15N tracer techniques at each N:P ratio. The growth rates suggested nutrient limitation at both high and low N:P ratios relative to the Redfield ratio. On a diel basis, the growth of both species was regulated by the light-dark cycle, which may be a result of regulation of both lightdependent growth and light-independent nutrient uptake. Maximum growth rates of both species always occurred at the beginning of light phase. In P-rich medium (low N:P ratio), both species had higher N assimilation rates, suggesting N limitation. Low assimilation coefficients at high N:P ratios suggested P limitation of N uptake and assimilation. NO{3/-} and NH{4/+} contributed more than 90% of the total N uptake of P. minimum. Reduced N sources were more quickly assimilated than NO{3/-}. Highest average daily growth rates were recorded near an N:P ratio of 12 for both species. The N uptake rates of cultures at N:P ratios near Redfield ratio were more balanced with growth rates. The linkage between growth rates and N uptake/assimilation rates were conceptually described by the variation of cell N quota. The N:P ratios affect the N uptake and growth of Prorocentrum spp., and may regulate their bloom progression in eutrophic ecosystems.

  16. Measurement of elemental speciation by liquid chromatography -- inductively coupled plasma mass spectrometry (LC-ICP-MS) with the direct injection nebulizer (DIN)

    SciTech Connect

    Shum, S.

    1993-05-01

    This thesis is divided into 4 parts: elemental speciation, speciation of mercury and lead compounds by microbore column LC-ICP-MS with direct injection nebulization, spatially resolved measurements of size and velocity distributions of aerosol droplets from a direct injection nebulizer, and elemental speciation by anion exchange and size exclusion chromatography with detection by ICP-MS with direct injection nebulization. Tabs, figs, refs.

  17. Interacción de resonancias y transición al caos en un modelo dinámico simple

    NASA Astrophysics Data System (ADS)

    Mestre, M.; Cincotta, P.; Giordano, C.

    In this paper we study the transition to global chaos in a perturbed 2D quartic oscillator. We estimate both, analitically and numerically, the intensity of the perturbation required to have the majority of the phase space dominated by a chaotic dynamics. FULL TEXT IN SPANISH

  18. IMPINGER SOLUTIONS FOR THE EFFICIENT CAPTURE OF GASEOUS MERCURY SPECIES USING DIRECT INJECTION NEBULIZATION INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY (DIN-ICP/MS) ANALYSIS

    EPA Science Inventory

    Currently there are no EPA reference sampling mehtods that have been promulgated for measuring Hg from coal combustion sources. EPA Method 29 is most commonly applied. The ASTM Ontario Hydro Draft Method for measuring oxidized, elemental, particulate-bound and total Hg is now und...

  19. EVALUATION OF IODINE BASED IMPINGER SOLUTIONS FOR THE EFFICIENT CAPTURE OF HG USING DIRECT INJECTION NEBULIZATION INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY (DIN-ICP/MS) ANALYSIS

    EPA Science Inventory

    Currently there are no EPA reference sampling methods that have been promulgated for measuring stack emissions of Hg from coal combustion sources, however, EPA Method 29 is most commonly applied. The draft ASTM Ontario Hydro Method for measuring oxidized, elemental, particulate-b...

  20. Non-invasive deformation analysis of historical buildings through the advanced SBAS-DInSAR technique: the case of the city of Roma (Italy)

    NASA Astrophysics Data System (ADS)

    Manunta, Michele; Bonano, Manuela; Marsella, Maria; Lanari, Riccardo

    2010-05-01

    The monitoring of urban areas and man-made structures is of key importance for the preservation of artistic, archaeological and architectural heritage. In this context, the remote sensing techniques may allow non-invasive analysis of large areas by exploiting long time series of satellite data. Among these techniques, the Synthetic Aperture Radar (SAR) Interferometry (InSAR) has already demonstrated to be an effective tool for monitoring the displacements occurring in the historical and artistic heritage located in the historical city centers. As a matter of fact, the InSAR technique allows producing spatially dense deformation maps with centimeter to millimeter accuracy, by exploiting the phase difference (interferogram) of temporally separated SAR images relevant to the same analyzed area. In order to guarantee the monitoring of urban area displacements, it is strategic to provide very long term deformation time series by also exploiting SAR data acquired by different sensors. Accordingly, ERS/ENVISAT data archive, providing acquisitions spanning the 1992-2010 time period, might allow us generating very long term deformation time-series. However, an ERS/ENVISAT data combination is limited by the two sensors slightly different carrier frequencies: 5.331 GHz for the ENVISAT sensor and 5.3 GHz for the ERS one. Therefore, because the interferometric phase is dependent on the radiation wavelength, the generation of conventional ERS/ENVISAT cross-interferograms is strongly affected by the induced decorrelation effects. In this work we show the effectiveness of the Small BAseline Subset (SBAS) (Berardino et al., 2002; Lanari et al., 2004) approach for the conservation, monitoring and risk prevention of cultural heritage. Indeed, the SBAS technique allows us to produce deformation time series at the scale of the single building by processing very long sequences of ERS-1/2 and ENVISAT (IS2 swath) SAR data, acquired with the same illumination geometry. In particular, the SBAS approach exploits only conventional ERS/ERS and ENVISAT/ENVISAT differential interferograms, in order to limit the decorrelation effects and improve the number of the detected coherent points. Accordingly, this method may play a key role for supporting the study and conservation strategies of the historical built heritage, monuments and artistic artifacts, due to its capability of generating deformation time series spanning time interval of more than 15 years. The presented results, achieved by applying the full resolution SBAS approach to an ERS/ENVISAT dataset relevant to the city of Rome, demonstrate the effectiveness of this technique to detect and analyze the temporal evolution of possible deformation phenomena affecting historical buildings within the investigated 1992-2009 time period. [1] P. Berardino, G. Fornaro, R. Lanari, and E. Sansosti, "A new Algorithm for Surface Deformation Monitoring based on Small Baseline Differential SAR Interferograms", IEEE Trans.Geosci. Remote Sens., Vol. 40, No 11, pp. 2375-2383, 2002. [2] Lanari, R., Mora, O., Manunta, M., Mallorquí, J.J., Berardino, P. and Sansosti, E., "A small baseline approach for investigating deformations on full resolution differential SAR interferograms", IEEE Transactions on Geoscience and Remote Sensing, Vol. 42, pp. 1377-1386, 2004.

  1. Pure flat epithelial atypia (DIN 1a) on core needle biopsy: study of 60 biopsies with follow-up surgical excision.

    PubMed

    Lavoué, Vincent; Roger, Claire Marie; Poilblanc, Mathieu; Proust, Nicolas; Monghal-Verge, Camille; Sagan, Christine; Tas, Patrick; Mesbah, Habiba; Porée, Philippe; Gay, Catherine; Body, Gilles; Levêque, Jean

    2011-01-01

    Flat epithelial atypia (FEA) is recognized as a precursor of breast cancer and its management (surgical excision or intensive follow-up) remains unclear after diagnosis on core needle biopsy (CNB). The aim of this study was to determine the underestimation rate of pure FEA on CNB and clinical, radiological, and pathological factors of underestimation. 4,062 CNBs from 5 breast cancer centers, performed over a 5-year period, were evaluated. A CNB diagnosis of pure FEA was made in 60 cases (1.5%) (the presence of atypical ductal hyperplasia, lobular neoplasia, radial scars, phyllodes tumor, papillary lesions, ductal carcinoma in situ or invasive carcinoma at CNB were exclusion criteria), and subsequent surgical excision was systematically performed. The histological diagnosis was retrospectively reviewed using standardized criteria and the precise terminology of the World Health Organization by two pathologist physicians. At surgical excision, 6 (10%) ductal carcinoma in situ and 2 (3%) invasive carcinoma were diagnosed. The total underestimation rate was 13%. FEA was associated with atypical ductal hyperplasia in 10 (17%) cases and with lobular neoplasia in 2 (3%) at final pathology. Residual FEA was found in 14 (23%) cases. No clinical, radiological or pathological factors were significantly associated with underestimation. Our data highlight the importance of recognizing and diagnosing FEA in core needle biopsies. Thus, the presence of FEA on CNB, even in isolation, warrants follow-up excision.

  2. Advanced DInSAR analysis for building damage assessment in large urban areas: an application to the city of Roma, Italy

    NASA Astrophysics Data System (ADS)

    D'Aranno, Peppe J. V.; Marsella, Maria; Scifoni, Silvia; Scutti, Marianna; Sonnessa, Alberico; Bonano, Manuela

    2015-10-01

    Remote sensing data play an important role for the environmental monitoring because they allow to provide systematic information on very large areas and for a long period of time. Such information must be analyzed, validated and incorporated into proper modeling tools in order to become useful for performing risk assessment analysis. These approaches has been already applied in the field of natural hazard evaluation (i.e. for monitoring seismic, volcanic areas and landslides). However, not enough attention has been devoted to the development of validated methods for implementing quantitative analysis on civil structures. This work is dedicated to the comprehensive utilization of ERS / ENVISAT data store ESA SAR used to detect deformation trends and perform back-analysis of the investigated structures useful to calibrate the damage assessment models. After this preliminary analysis, SAR data of the new satellite mission (ie Cosmo SkyMed) were adopted to monitor the evolution of existent surface deformation processes and to detect new occurrence. The specific objective was to set up a data processing and data analysis chain tailored on a service that sustains the safe maintenance of the built-up environment, including critical construction such as public (schools, hospital, etc), strategic (dam, highways, etc) and also the cultural heritage sites. The analysis of the test area, in the southeastern sector of Roma, has provided three different levels and sub-levels of products from metropolitan area scale (territorial analysis), settlement scale (aggregated analysis) to single structure scale (damage degree associated to the structure).

  3. Global distribution and sources of dissolved inorganic nitrogen export to the coastal zone: Results from a spatially explicit, global model

    NASA Astrophysics Data System (ADS)

    Dumont, E.; Harrison, J. A.; Kroeze, C.; Bakker, E. J.; Seitzinger, S. P.

    2005-12-01

    Here we describe, test, and apply a spatially explicit, global model for predicting dissolved inorganic nitrogen (DIN) export by rivers to coastal waters (NEWS-DIN). NEWS-DIN was developed as part of an internally consistent suite of global nutrient export models. Modeled and measured DIN export values agree well (calibration R2 = 0.79), and NEWS-DIN is relatively free of bias. NEWS-DIN predicts: DIN yields ranging from 0.0004 to 5217 kg N km-2 yr-1 with the highest DIN yields occurring in Europe and South East Asia; global DIN export to coastal waters of 25 Tg N yr-1, with 16 Tg N yr-1 from anthropogenic sources; biological N2 fixation is the dominant source of exported DIN; and globally, and on every continent except Africa, N fertilizer is the largest anthropogenic source of DIN export to coastal waters.

  4. Specific Saccharomyces cerevisiae genes are expressed in response to DNA-damaging agents.

    PubMed Central

    Ruby, S W; Szostak, J W

    1985-01-01

    When exposed to DNA-damaging agents, the yeast Saccharomyces cerevisiae induces the expression of at least six specific genes. We have previously identified one damage inducible (DIN) gene as a gene fusion (din-lacZ fusion) whose expression increases in response to DNA-damaging treatments. We describe here the identification of five additional DIN genes as din-lacZ fusions and the responses of all six DIN genes to DNA-damaging agents. Northern blot analyses of the transcripts of two of the DIN genes show that their levels increase after exposure to DNA-damaging agents. Five of the din-lacZ fusions are induced in S. cerevisiae cells exposed to UV light, gamma rays, methotrexate, or alkylating agents. One of the din-lacZ fusions is induced by either UV or methotrexate but not by the other agents. This finding suggests that there are sets of DIN genes that are regulated differently. Images PMID:3920512

  5. Climate dynamics along the arid northern coast of Chile: The 1997-1998 Dinámica del Clima de la Región de Antofagasta (DICLIMA) experiment

    NASA Astrophysics Data System (ADS)

    Rutllant, José A.; Fuenzalida, Humberto; Aceituno, Patricio

    2003-09-01

    The DICLIMA field experiment was designed to test and quantify the hypothesis of an afternoon enhancement of the coastal subsidence in the extremely arid northern Chile because of solar heating over the west slope of the Andes. Ten-day campaigns near Antofagasta (23°S) were carried out in January 1997, July 1997, and January 1998. Significant diurnal cycles in temperature, mixing ratio, and wind from about 1000 to 4000 m above sea level were observed. This layer was decoupled from the marine boundary layer circulation below by the subsidence inversion when its base was under the average height of the coastal mountain range. The solar heating cycle over the Andes and associated circulation resulted in a mean afternoon zonal divergence above the subsidence inversion base of about 30 × 10-6 s-1, exceeding by a factor of 5 typical subtropical west coast divergences. The corresponding early morning convergence was particularly intense during the austral winter experiment. In spite of the very strong El Niño conditions that prevailed during the July 1997 and January 1998 experiments, the overwhelming control that radiation exerts on the daily cycles of the atmospheric circulation over the west slope of the Andes seems to guarantee the general validity of the results.

  6. Simulación mediante ondas de choque de la dinámica de abrillantamientos en arcos magnéticos de la baja corona solar. Comparación con observaciones

    NASA Astrophysics Data System (ADS)

    Fernández, C.; Costa, A.; Elaskar, S.; Schulz, W.

    We simulated brightening sliding down along a coronal loop. We solved the MHD equations with a finite volume scheme centered in cells. For the numerical fluxes we used a TVD scheme of Harten-Yee with an approximate Riemann solver. We reproduced observational curves that describe the dynamics of loop brightening as shock waves. FULL TEXT IN SPANISH

  7. Impact of surface disinfection and sterile draping of furniture on room air quality in a cardiac procedure room with a ventilation and air-conditioning system (extrusion airflow, cleanroom class 1b (DIN 1946-4)).

    PubMed

    Below, Harald; Ryll, Sylvia; Empen, Klaus; Dornquast, Tina; Felix, Stefan; Rosenau, Heike; Kramer, Sebastian; Kramer, Axel

    2010-09-21

    In a cardiac procedure room, ventilated by a ventilation and air-conditioning system with turbulent mixed airflow, a protection zone in the operating area could be defined through visualization of airflows. Within this protection zone, no turbulence was detectable in the room air.Under the given conditions, disinfection of all surfaces including all furniture and equipment after the last operation and subsequent draping of furniture and all equipment that could not be removed from the room with sterile surgical drapes improved the indoor room air quality from cleanroom class C to cleanroom class B. This also allows procedures with elevated requirements to be performed in room class 1b.

  8. Estimation of Seismic and Aseismic Deformation in Mexicali Valley, Baja California, Mexico, in the 2006-2009 Period, Using Precise Leveling, DInSAR, Geotechnical Instruments Data, and Modeling

    NASA Astrophysics Data System (ADS)

    Sarychikhina, Olga; Glowacka, Ewa; Robles, Braulio; Nava, F. Alejandro; Guzmán, Miguel

    2015-11-01

    Ground deformation and seismicity in Mexicali Valley, Baja California, Mexico, the southern part of the Mexicali-Imperial valley, are influenced by active tectonics and human activity. In this study, data from two successive leveling surveys in 2006 and 2009/2010 are used to estimate the total deformation occurred in Mexicali Valley during 2006-2009. The leveling data span more than 3.5 years and include deformation from several natural and anthropogenic sources that acted at different temporal and spatial scales during the analyzed period. Because of its large magnitude, the aseismic anthropogenic deformation caused by fluid extraction in the Cerro Prieto geothermal field obscures the deformation caused by other mechanisms and sources. The method of differential interferograms stacking was used to estimate the aseismic (interseismic tectonic and anthropogenic) components of the observed displacement, using SAR images, taken in 2007 during a period when no significant seismicity occurred in the study area. After removing the estimated aseismic signal from the leveling data, residual vertical displacement remained, and to identify possible sources and mechanisms of this displacement, a detailed analysis of records from tiltmeters and creepmeters was performed. The results of this analysis suggest that the residual displacement is mainly caused by moderate-sized seismicity in the area of study. Modeling of the vertical ground deformation caused by the coseismic slip on source fault (primary mechanism) of the two most important earthquakes, May 24, 2006 (Mw = 5.4) and December 30, 2009 (Mw = 5.8), was performed. The modeling results, together with the analysis of geotechnical instruments data, suggests that this moderate-sized seismicity influences the deformation in the study area by coseismic slip on the source fault, triggered slip on secondary faults, and soft sediments deformation.

  9. Effect of Orem Self-Care Program on the Life Quality of Burn Patients Referred to Ghotb-al-Din-e-Shirazi Burn Center, Shiraz, Iran: A Randomized Controlled Trial

    PubMed Central

    Hashemi, Fatemeh; Rahimi Dolatabad, Fatemeh; Yektatalab, Shahrzad; Ayaz, Mehdi; Zare, Najaf; Mansouri, Parisa

    2014-01-01

    Background: Advances in treatment and critical care have largely improved the survival following burns; therefore, the importance of quality of life in burn patients is an issue beyond question. The aim of this study was to determine the effects of Orem self-care program on Quality of Life of burn patients. Methods: A randomized clinical trial study was conducted on 110 eligible burn patients who were selected using easy sampling method and allocated randomly into two groups of experiment and control. The instrument for data collection was a questionnaire, containing demographic and burn information and burn-specific health scale–brief (BSHS-B) questionnaire. For the experiment group, 5 sessions of theoretical training and 75-90 minutes of practical training were accomplished. The quality of life of the patients with burns was assessed in three phases by the BSHS-B questionnaire. The data were analyzed in SPSS-17 using Chi-square test, Fisher’s exact test, Independent t-test and repeated measurement multivariate test. Results: After one month and two months of the use of self-care model, the quality of life of the cases improved from 73.33% to 83.78% and 98.12%, respectively (P<0.001). But the changes in the quality of life of the patients in the control group were not statistically significant (P>0.05). Conclusion: Based on the obtained results of this study, designing and implementing a self-care program based on Orem’s model and the needs of burn patients will improve their quality of life. Therefore, it is recommended that this program should be considered as a part of treatment program for these patients. Trial Registration Number: 2013042112129N1 PMID:25349844

  10. Factors Influencing Export Of Dissolved Inorganic Nitrogen By Major Rivers: A New, Seasonal, Spatially Explicit, Global Model

    NASA Astrophysics Data System (ADS)

    McCrackin, M. L.; Harrison, J.; Compton, J.

    2013-12-01

    Substantial effort has focused on understanding spatial variation in dissolved inorganic nitrogen (DIN) export to the coastal zone and specific basins have been studied in depth. Much less is known, however, about seasonal patterns and controls of coastal DIN delivery across large spatial scales. Understanding sub-annual patterns and delivery DIN export from rivers to coastal areas is critical to efforts to predict impacts of coastal eutrophication, such as algal blooms and hypoxic areas, which are often seasonal phenomena. Here we describe, test, and apply NEWS2-DIN-S, the first global model capable of predicting seasonal DIN export to coastal regions for over 6,000 rivers for the contemporary period (2000). NEWS2-DIN-S used spatially explicit, seasonal N-inputs and was calibrated with measured DIN yield (kg N km-2 y-1) for 75 global rivers. Of the catchment characteristics considered, DIN export was positively related to runoff and negatively related to temperature across seasons (r2 = 0.39-0.95, p<0.0001, depending on season), due likely to flushing effects and increased retention by plants and soils, respectively. NEWS2-DIN-S incorporated these insights and performed well in predicting DIN yield (Nash-Sutcliffe Efficiency = 0.44-0.65, depending on season). Model runs showed that catchments were effective in retaining DIN and average export rates were generally lower during the growing season (3-5%) compared to other seasons (6-10%) for major latitude bands. Model output was relatively insensitive to changes in the magnitude of N inputs, suggesting that further refinement of seasonal N budgets will not substantially improve predictive performance. Rather, better representation of land-to-river N transfers could improve the predictive capacity of future models because of the importance of landscape N-attenuation.

  11. The Influence of Sediment Size on Dissolved Inorganic Nitrogen in Hyporheic Mesocosms

    NASA Astrophysics Data System (ADS)

    Harvey, B. N.; Johnson, M. L.; Kiernan, J. D.; Green, P. G.

    2007-12-01

    Dissolved inorganic nitrogen (DIN) is composed of nitrate, nitrite and ammonia. The availability of DIN in streams is important to water quality and to stream ecosystems in general because at low concentrations DIN can limit primary productivity, while at high concentrations DIN contributes to eutrophication. An important location of nitrogen transformations in streams is the interstitial spaces between streambed sediments. As surface water passes transiently along shallow subsurface flow paths, the activities of interstitial biofilms and invertebrates alter the form and availability of nitrogen. Heterotrophic consumers release nitrogen as ammonia. Nitrifying bacteria further transform ammonia to nitrate under aerobic conditions. While under anaerobic conditions denitrifying bacteria can transform nitrate to nitrogen gas. Studies in natural streambeds have suggested the size of streambed sediments can influence whether the streambed serves as a net source or sink for DIN in transient sub-surface water. We tested whether the size distribution of streambed sediments in isolation from the effects of streambed topography and groundwater upwelling could alter DIN production or uptake as stream water passed transiently along interstitial flow paths. We filled pipes with contrasting sediment mixes, and placed them in a stream so that surface water flowed through the sediments. After an incubation period allowing biofilm development, we measured nitrate + nitrite and ammonia in interstitial water drawn at several distances along the pipes. These measurements revealed that both sediment types were net sources of DIN, with the majority of DIN production occurring near the beginning of subsurface flow paths. Concentrations of DIN were greater in the finer sediments at any given distance along the pipes. However, higher surface water exchange rates through the coarser sediments caused net DIN production in the coarse sediments, and therefore DIN release to surface water, to

  12. Factors influencing export of dissolved inorganic nitrogen by major rivers: A new, seasonal, spatially explicit, global model

    NASA Astrophysics Data System (ADS)

    McCrackin, Michelle L.; Harrison, John A.; Compton, Jana E.

    2014-03-01

    Substantial effort has focused on understanding spatial variation in dissolved inorganic nitrogen (DIN) export to the coastal zone and specific basins have been studied in depth. Much less is known, however, about seasonal patterns and controls of coastal DIN delivery across large spatial scales. Understanding seasonal patterns of DIN export is critical to efforts to predict impacts of coastal eutrophication, such as algal blooms and hypoxic areas, which are often seasonal phenomena. Here we describe, test, and apply a global model that predicts seasonal DIN export to coastal regions for >6000 rivers using the Nutrient Export from Watersheds (NEWS2) model. NEWS2-DIN-S used spatially explicit, seasonal N inputs and was calibrated with measured DIN yield (kg N km-2 season-1) for 77 rivers, distributed globally. Of the characteristics considered, DIN-transport efficiency was positively related to runoff and negatively related to temperature (r2 = 0.34-0.60, depending on season p < 0.0001), likely due to flushing effects and increased retention by plants and soils, respectively. NEWS2-DIN-S incorporated these insights and performed well in predicting DIN yield (Nash-Sutcliffe Efficiency = 0.54-0.65, depending on season). Catchments were effective in retaining DIN and average export rates were lower during the growing season (3-5% of total nitrogen inputs) compared to other seasons (6-10%) for major latitude bands. Model output was insensitive to changes in the magnitude of N inputs, suggesting that refinement of seasonal N input budgets will not substantially improve model performance. Rather, better representation of land-to-river N transfers could improve future models because of strong landscape N attenuation.

  13. Análisis de la evolución química de los cúmulos abiertos de la Galaxia a través de simulaciones dinámicas con procesos de destrucción

    NASA Astrophysics Data System (ADS)

    Bignone, L. A.; Pellizza, L. J.; Piatti, A. E.; Tecce, T. E.

    It is well known that open clusters are excellent tracers (in time and space) of the metallicity of the Galactic disk. We analyze the history of stellar for- mation of the Galactic disk using numerical simulations of the dynamical evolution of the open cluster system. We have included the effects of clus- ter disruption caused by stellar evolution, tidal fields, and the interaction with the spiral arms. We model the present astrophysical properties of open clusters from initial hypothesis regarding their formation history. FULL TEXT IN SPANISH

  14. All the king's horses and 2,4,5-T was the best tool of all; yet 2,4,5-T had a very great fall. All of the facts midst all of the din couldn't put T back together again

    SciTech Connect

    Walstad, J.D.; Dost, F.N.

    1986-09-01

    On January 30 and February 11, 1985, the Environmental Protection Agency (EPA) canceled the use of 2,4,5-T and of silvex, a chemical analog of 2,4,5-T. These actions climaxed the most controversial and turbulent period in the history of forest pest management. Beginning in 1969, stories about 2,4,5-T safety generated intense social activism, litigation, and sometimes violence. Foresters, farmers, ranchers, politicians, manufacturers, environmentalists, scientists, regulatory officials, and local citizens entered the debate. The role of government in pesticide regulation and the integrity of industry and science were being challenged. Although 2,4,5-T and silvex are no longer used, questions remain. Were the ultimate decisions the result of scientific evidence and analysis, or were they a response to public opinion that with all the smoke there must be fire somewhere. Can forestry professionals help the nation avoid controversies of this nature in the future.

  15. Poly[di-methyl-ammonium [(μ2-benzene-1,2-di-carboxyl-ato-κ(2) O (1):O (3))[μ2-3-(pyri-din-4-yl)-1H-pyrazol-1-ido-κ(2) N (1):N (3)]cuprate(II)

    PubMed

    Na, Liu

    2013-01-01

    In the title complex, {(C2H8N)[Cu(C8H4O4)(C8H6N3)]} n , there are two Cu(II) cations (each located on a centre of inversion), one benzene-1,2-di-carboxyl-ate dianion, one 3-(pyridin-4-yl)-1H-pyrazol-1-ide anion and one di-methyl-ammonium cation in the asymmetric unit. The di-methyl-ammonium cation was highly disordered and was treated with the SQUEEZE routine in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148-155]; the crystallographic data takes into account the presence of the cation. Each Cu(II) cation exhibits a square-planar coordination geometry. A benzene-1,2-di-carboxyl-ate dianion bridges two Cu(II) cations, building a linear chain along [001]. The chains are connected by 3-(pyridin-4-yl)-1H-pyrazol-1-ide anions, constructing a layer parallel to (101). The layers are assembled into a three-dimensional supra-molecular network through C-H⋯π inter-actions. PMID:24046573

  16. Invatamantul cu Predarea in Limbile Minoritatilor Nationale din Romania. In Anul Scolar 1992/1993 = The Education System in Romania: Tuition in the Languages of Ethnic Minorities. The School Year 1992/1993 = L'enseignement dispense dans les langues des minorites nationales de Roumanie. L'annee scolaire 1992/1993.

    ERIC Educational Resources Information Center

    Council for National Minorities, Bucharest (Romania).

    Documentation of the Romanian system of language instruction in ethnic minority languages is presented in Romanian, French, and English. It consists of: relevant provisions from the national constitution concerning the rights of ethnic minority members; organization and functioning of the educational system at the elementary, middle, and secondary…

  17. Factors influencing export of dissolved inorganic nitrogen by major rivers: A new, seasonal, spatially explicit, global model

    EPA Science Inventory

    Substantial effort has focused on understanding spatial variation in dissolved inorganic nitrogen (DIN) export to the coastal zone and specific basins have been studied in depth. Much less is known, however, about seasonal patterns and controls of coastal DIN delivery across larg...

  18. A retrospective analysis of nutrients and phytoplankton productivity in the Mississippi River plume

    NASA Astrophysics Data System (ADS)

    Lohrenz, Steven E.; Redalje, Donald G.; Cai, Wei-Jun; Acker, James; Dagg, Michael

    2008-07-01

    Long-term patterns in riverine nutrient flux in the lower Mississippi River were examined in relationship to spatial and temporal patterns in surface nutrient concentrations, chlorophyll, and primary productivity in the outflow region in the northern Gulf of Mexico. A retrospective analysis of dissolved inorganic nutrient fluxes based on USGS water quality data and US Army Corps of Engineers discharge data from the 1950s to mid-2004 showed an increase in river-borne dissolved inorganic nitrogen (DIN) flux after 1967. Flux of DIN peaked in the early 1980s and has since fluctuated and shown a general decreasing trend since the early 1990s. Records for total phosphorus (total P) fluxes beginning in mid-1974 exhibited a variable but slight increasing trend up to 2004. The increase in fluxes during the 1970s and into the 1980s can be attributed to increases in both nutrient concentrations and river discharge. DIN concentrations since the 1980s have shown a decreasing trend. Total P concentrations exhibited large fluctuations, with no consistent long-term trend. Dissolved organic nitrogen (DON) concentrations and orthophosphate (Ortho P) peaked in the 1980s, declined relative to DIN and remained relatively low. DIN:Ortho P ratios were consistently well above the Redfield N:P ratio of 16:1. DIN:Total P ratios were variable and lower, fluctuating around the Redfield 16:1 value. Both DIN:Ortho P and DIN:Total P ratios were weakly, but significantly, correlated with river discharge and fluctuations were largely a reflection of higher DIN concentrations during high-discharge events. DIN:Ortho P ratios in surface waters of the outflow region adjacent to the birdfoot delta were higher in spring, consistent with seasonal variation in riverine DIN:Ortho P ratios. The seasonal signal diminished with increasing distance to the west of the delta, indicating a selective removal of DIN or source of Ortho P along the shelf. DIN fluxes and SeaWiFS satellite-derived chlorophyll showed

  19. Characterising the fate of nitrogenous waste from the sea-cage aquaculture of spiny lobsters using numerical modelling.

    PubMed

    Lee, Soxi; Hartstein, Neil D; Jeffs, Andrew

    2015-06-01

    Although the aquaculture of spiny lobsters has been expanding since the 1970s, very little is known about the potential environmental impacts on water quality of this activity. This study quantified the production of dissolved inorganic nitrogen (DIN) from Australasian red spiny lobsters, Jasus edwardsii, in the laboratory, and these data were then used in a numerical model to predict the dispersal pattern of DIN from a hypothetical commercial spiny lobster farm for a coastal site where such a farm would typically be located. Modelling scenarios were set up with combinations of two different stocking densities (3 and 5 kg m(-3)), two different diets (mussels and moist artificial diet) and three different feed conversion ratios (FCR = 3, 5 and 28). DIN excretion rate from unfed lobsters in the laboratory on average was 1.10 ± 0.12 μg N g(-1) h(-1) while feeding lobsters on mussels and artificial diet increased DIN excretion significantly by around eightfold and twofold, respectively. Ammonia was consistently the dominant contributor to measured DIN output from lobsters. Modelling results indicated that the mean elevated DIN from a hypothetical farm where the lobsters were fed with mussels ranged from 7 up to 20 μg N L(-1) with increasing stocking density and FCR and was 30-150 % higher than the mean elevated DIN resulting from lobsters fed with artificial diet. Overall, the results indicated that DIN output from the hypothetical spiny lobster sea-cage farming is unlikely to be problematic using the FCR, stocking density, and the number of cages modelled at the coastal site in this study. Furthermore, feeding lobsters with artificial diet can help maintain a lower DIN output than seafood, such as mussels or trash fish.

  20. Nitrogen export from a boreal stream network following forest harvesting: seasonal nitrate removal and conservative export of organic forms

    NASA Astrophysics Data System (ADS)

    Schelker, J.; Sponseller, R.; Ring, E.; Högbom, L.; Löfgren, S.; Laudon, H.

    2016-01-01

    Clear-cutting is today the primary driver of large-scale forest disturbance in boreal regions of Fennoscandia. Among the major environmental concerns of this practice for surface waters is the increased mobilization of nutrients, such as dissolved inorganic nitrogen (DIN) into streams. But while DIN loading to first-order streams following forest harvest has been previously described, the downstream fate and impact of these inputs is not well understood. We evaluated the downstream fate of DIN and dissolved organic nitrogen (DON) inputs in a boreal landscape that has been altered by forest harvests over a 10-year period. The small first-order streams indicated substantial leaching of DIN, primarily as nitrate (NO3-) in response to harvests with NO3- concentrations increasing by ˜ 15-fold. NO3- concentrations at two sampling stations further downstream in the network were strongly seasonal and increased significantly in response to harvesting at the mid-sized stream, but not at the larger stream. DIN removal efficiency, Er, calculated as the percentage of "forestry derived" DIN that was retained within the stream network based on a mass-balance model was highest during the snowmelt season followed by the growing season, but declined continuously throughout the dormant season. In contrast, export of DON from the landscape indicated little removal and was essentially conservative. Overall, net removal of DIN between 2008 and 2011 accounted for ˜ 65 % of the total DIN mass exported from harvested patches distributed across the landscape. These results highlight the capacity of nitrogen-limited boreal stream networks to buffer DIN mobilization that arises from multiple clear-cuts within this landscape. Further, these findings shed light on the potential impact of anticipated measures to increase forest yields of boreal forests, such as increased fertilization and shorter forest rotations, which may increase the pressure on boreal surface waters in the future.

  1. Speciation and dynamics of dissolved inorganic nitrogen export in the Danshui River, Taiwan

    NASA Astrophysics Data System (ADS)

    Lee, T.-Y.; Shih, Y.-T.; Huang, J.-C.; Kao, S.-J.; Shiah, F.-K.; Liu, K.-K.

    2014-10-01

    Human-induced excess nitrogen outflowing from land through rivers to oceans has resulted in serious impacts on terrestrial and coastal ecosystems. Oceania, which occupies < 2.5% of the global land surface, delivers 12% of the freshwater and dissolved materials to the ocean on a global scale. However, there are few empirical data sets on riverine dissolved inorganic nitrogen (DIN) fluxes in the region, and their dynamics are poorly understood. In this study, a river monitoring network covering different types of land uses and population densities was implemented to investigate the mechanism of DIN export. The results show that DIN concentration/yield varied from ∼20 μM/∼300 kg-N km-2 yr-1 to ∼378 μM/∼10 000 kg-N km-2 yr-1 from the relatively pristine headwaters to the populous estuary. Agriculture and population density control DIN export in less densely populated regions and urban areas, respectively, and runoff controls DIN at the watershed scale. Compared to documented estimates from global models, the observed DIN export from the Danshui River is 2.3 times larger, which results from the region-specific response of DIN yield to dense population and abundant runoff. The dominating DIN species change gradually from NO3- in the headwaters (∼97%) to NH4+ in the estuary (∼60%) following the urbanization gradient. The prominent existence of NH4+ is probably the result of the anaerobic water body and short residence time, unlike in large river basins. Given the analogous watershed characteristics of the Danshui River to the rivers in Oceania, our study could serve as a first example to examine riverine DIN fluxes in Oceania.

  2. Characterising the fate of nitrogenous waste from the sea-cage aquaculture of spiny lobsters using numerical modelling.

    PubMed

    Lee, Soxi; Hartstein, Neil D; Jeffs, Andrew

    2015-06-01

    Although the aquaculture of spiny lobsters has been expanding since the 1970s, very little is known about the potential environmental impacts on water quality of this activity. This study quantified the production of dissolved inorganic nitrogen (DIN) from Australasian red spiny lobsters, Jasus edwardsii, in the laboratory, and these data were then used in a numerical model to predict the dispersal pattern of DIN from a hypothetical commercial spiny lobster farm for a coastal site where such a farm would typically be located. Modelling scenarios were set up with combinations of two different stocking densities (3 and 5 kg m(-3)), two different diets (mussels and moist artificial diet) and three different feed conversion ratios (FCR = 3, 5 and 28). DIN excretion rate from unfed lobsters in the laboratory on average was 1.10 ± 0.12 μg N g(-1) h(-1) while feeding lobsters on mussels and artificial diet increased DIN excretion significantly by around eightfold and twofold, respectively. Ammonia was consistently the dominant contributor to measured DIN output from lobsters. Modelling results indicated that the mean elevated DIN from a hypothetical farm where the lobsters were fed with mussels ranged from 7 up to 20 μg N L(-1) with increasing stocking density and FCR and was 30-150 % higher than the mean elevated DIN resulting from lobsters fed with artificial diet. Overall, the results indicated that DIN output from the hypothetical spiny lobster sea-cage farming is unlikely to be problematic using the FCR, stocking density, and the number of cages modelled at the coastal site in this study. Furthermore, feeding lobsters with artificial diet can help maintain a lower DIN output than seafood, such as mussels or trash fish. PMID:25601612

  3. Early results from an effort to downscale a global dissolved inorganic nitrogen model to achieve a regional assessment of nitrogen dynamics in the Columbia River Basin

    NASA Astrophysics Data System (ADS)

    Miller, C. C.; Harrison, J.

    2013-12-01

    Excessive nitrogen (N) export to coastal systems has increased dramatically since the early 20th century. The increase in N has been linked to significant environmental impacts such as eutrophication, fish kills, and harmful algal blooms and is caused in part by the increasing use and quantity of synthetic fertilizer on farmland. Significant portions of both the Willamette River Valley in Oregon and the Palouse region of eastern Washington are agricultural land, approximately 20% and 57% respectively. Nitrogen in the form of dissolved inorganic nitrogen (DIN) can leach from farms and pasture land into ground and surface water systems. This leaching, combined with DIN in runoff, contributes to the environmental degradation of both waterways (i.e. streams, rivers) and coastal estuaries. Because of this it is important to understand what effects changes in DIN application will have on water quality and DIN export to the coast. DIN export data, retrieved from the U.S. Geological Survey National Water Information System, was analyzed for 23 major subbasins in the Columbia River Basin (CRB) and estimates DIN export (per area yield) ranging from 5.0 to 883.1 kg N km-2 yr-1. Here we present early results from our effort to downscale the Global Nutrient Export from WaterSheds (Global NEWS) DIN model for application within the Columbia River Basin (CRB). This first attempt at downscaling Global NEWS is missing some key higher-resolution N inputs for the model as well as accurate dam retention and runoff factors which could account for the low correlation between model output and observed data (R2 = 0.21).Our regional model predicts DIN yields ranging from 7.9 to 1146.6 kg N km-2 yr-1. Both the model output and observed data predict the highest per area DIN yields occurring in the Willamette river subbasin. Total DIN export to the coast was modeled as 0.06 Tg N yr-1 compared to 0.07 Tg N yr-1 calculated from the measured data. Based on current model inputs biological N2

  4. Temporal variation of nitrate and phosphate transport in headwater catchments: the hydrological controls and land use alteration

    NASA Astrophysics Data System (ADS)

    Lee, T.-Y.; Huang, J.-C.; Kao, S.-J.; Tung, C.-P.

    2013-04-01

    Oceania rivers are hotspots of DIN (dissolved inorganic nitrogen) and DIP (dissolved inorganic phosphorus) transport due to humid/warm climate, typhoon-induced episodic rainfall and high tectonic activity that create an environment favorable for high/rapid runoff and soil erosion. In spite of its uniqueness, effects of hydrologic controls and land use on the transport behaviors of DIN and DIP are rarely documented. A 2 yr monitoring study for DIN and DIP from three headwater catchments with different cultivation gradient (0 To 8.9%) was implemented during a ~ 3 day interval with an additional monitoring campaign at a 3 h interval during typhoon periods. Results showed the DIN yields in the pristine, moderately cultivated (2.7%), and intensively cultivated (8.9%) watersheds were 8.3, 26, and 37 kg N ha-1 yr-1, respectively. For the DIP yields, they were 0.36, 0.35, and 0.56 kg P ha-1 yr-1, respectively. Higher year-round DIN concentrations and five times larger in DIN yields in intensively cultivated watersheds indicate DIN is more sensitive to land use changes. The high background DIN yield from the relatively pristine watershed was likely due to high atmospheric nitrogen deposition and large subterranean N pool. The correlations between runoff and concentration reveals that typhoon floods purge out more DIN from the subterranean reservoir, i.e., soil, by contrast, runoff washes off surface soil resulting in higher suspended sediment with higher DIP. Collectively, typhoon runoff contributes 20-70% and 47-80%, respectively, to the annual DIN and DIP exports. The DIN yield to DIP yield ratio varied from 97 to 410, which is higher than the global mean of ~ 18. Such a high ratio indicates a P-limiting condition in stream and the downstream aquatic environment. Based on our field observation, we constructed a conceptual model illustrating different remobilization mechanisms for DIN and DIP from headwaters in a mountainous river, which is analogous to typical Oceania

  5. Assessing dissolved inorganic nitrogen flux in the Yangtze River, China: Sources and scenarios

    NASA Astrophysics Data System (ADS)

    Xu, Hao; Chen, Zhongyuan; Finlayson, Brian; Webber, Michael; Wu, Xiaodan; Li, Maotian; Chen, Jing; Wei, Taoyuan; Barnett, Jon; Wang, Mark

    2013-07-01

    This study gives a thorough assessment of the occurrences of dissolved inorganic nitrogen (DIN) in the Yangtze River in the past half century. The results have shown that nitrogen fertilizer, a major DIN source, has been replaced by domestic sewage in the last decade, which has dramatically driven up DIN loads in the Yangtze. DIN concentrations showed a rapid increase from < 0.5 mg L- 1 in the 1960s to nearly 1.5 mg L- 1 at the end of the 1990s. Since then DIN has remained steady at ca. 1.6-1.8 mg L- 1. A significant relationship between the historical DIN record at the downstream gauging station (Datong) and nitrogen (N) sources in the Yangtze River basin is established using principal components analysis. This allows us to apportion DIN loads for the year 2007 (the most recent year of measured DIN data available) to various N sources, listed here in order of weight: sewage (0.391 million tons); atmosphere (0.358 million tons); manure (0.318 million tons), N-fertilizer (0.271 million tons). Therefore, we estimated that a DIN load of 1.339 × 106 t was delivered to the lower Yangtze and its estuarine water in that year. We established scenarios to predict DIN concentrations in the lower Yangtze at 10 year intervals to 2050. For a dry year (20,000 m3 s- 1) DIN concentrations would range from 2.2-3.0 mg L- 1 for 2020-2050. This far exceeds the 2.0 mg L- 1 defined on the Chinese National Scale as the worst class for potable source water. The scenario results suggest that upgrading the sewage treatment systems throughout the basin will be an effective way to help reduce DIN concentrations to less than 2.0 mg L- 1 in the lower Yangtze. This would save the Shanghai megacity from the increasing threat of heavily polluted water sources, where > 23 million people are at present dependent on the Yangtze estuary for 70% of their freshwater intake.

  6. Blessed by the Holy People.

    PubMed

    House, Carrie

    2016-01-01

    Men-women and women-men have a long tradition in Diné (Navajo) culture where they were, and sometimes still are, held in high esteem. Their supernatural prototypes figure prominently in parts of the Diné Origin Story. It is in this cosmological worldview and tradition of acceptance that Carrie, a multi-dualistic spirit, grew up to be a female-bodied man supported and respected by his/her family and community. He/she has worked in various professions defined as "masculine" in Diné and Western contexts, such as fire fighter, heavy equipment operator, truck driver, and building contractor. In addition, Carrie is a keeper of Diné traditions, and has also been active educating Native and Non-Native audiences on 2SpiritLesbianGayBiTransIntersexQueer issues.

  7. Factors influencing export of dissolved inorganic nitrogen by major rivers: A new seasonal, global-scale model

    EPA Science Inventory

    Understanding sub-annual patterns of catchment dissolved inorganic nitrogen (DIN) export is critical for predicting and mitigating impacts of coastal eutrophication, such as algal blooms and hypoxic areas, which are often seasonal phenomena. We developed the first calibrated glob...

  8. Evolution of Hydrogen Dynamics in Amorphous Ice with Density.

    PubMed

    Parmentier, A; Shephard, J J; Romanelli, G; Senesi, R; Salzmann, C G; Andreani, C

    2015-06-01

    The single-particle dynamics of hydrogen atoms in several of the amorphous ices are reported using a combination of deep inelastic neutron scattering (DINS) and inelastic neutron scattering (INS). The mean kinetic energies of the hydrogen nuclei are found to increase with increasing density, indicating the weakening of hydrogen bonds as well as a trend toward steeper and more harmonic hydrogen vibrational potential energy surfaces. DINS shows much more pronounced changes in the O-H stretching component of the mean kinetic energy going from low- to high-density amorphous ices than indicated by INS and Raman spectroscopy. This highlights the power of the DINS technique to retrieve accurate ground-state kinetic energies beyond the harmonic approximation. In a novel approach, we use information from DINS and INS to determine the anharmonicity constants of the O-H stretching modes. Furthermore, our experimental kinetic energies will serve as important benchmark values for path-integral Monte Carlo simulations.

  9. Chemical control of photochromism and a multiresponsive molecular switch based on a diarylethene derivative containing naphthol.

    PubMed

    Liu, Wenju; Li, Ziyong; Hu, Fang; Yin, Jun; Yu, Guang-Ao; Liu, Sheng Hua

    2014-12-01

    A photochemically inactive diarylethene derivative with a naphthol group bridging through the imidazole unit (DIN) was synthesized to characterize a multifunctional switch. Upon stimulation by radiation (UV and visible light), the target diarylethene derivative DIN was not photochemically inactive but photo-active, it could be photo-converted into a keto compound. Moreover, the photochromic reaction of DIN was observed when it was stimulated by the addition of acid or methylation. Fluorescence quenching and the bathochromic effect occurred when DIN was stimulated by the addition of copper ions and a base, respectively. Its optical properties could be regulated by various chemical stimuli. Thus, it can potentially be utilized as a multiresponsive molecular switch. PMID:25341073

  10. Effect of enhanced reactive nitrogen availability on plant-sediment mediated degradation of polycyclic aromatic hydrocarbons in contaminated mangrove sediment.

    PubMed

    Jiang, Shan; Lu, Haoliang; Zhang, Qiong; Liu, JingChun; Yan, Chongling

    2016-02-15

    As land-ocean interaction zones, mangrove systems receive substantial polycyclic aromatic hydrocarbons (PAHs) from sewage and combustion of fossil fuel. In this study, we investigated the relationship between dissolved inorganic nitrogen (DIN) availability and degradation rate of phenanthrene, a typical PAH compound, in mangrove plant-sediment systems, using Avicennia marina as a model plant. After 50 day incubation, phenanthrene removal ratios in sediments ranged from 53.8% to 97.2%. In non-rhizosphere sediment, increasing DIN accessibility increased microbial biomass and total microbial activity, while enhancements in population size of phenanthrene degradation bacteria (PDB) and phenanthrene degradation rates were insignificant. In contrast, the presence of excessive DIN in rhizosphere sediment resulted in a significantly large number of PDB, leading to a rapid dissipation rate of phenanthrene. The differences in degradation rates and abundances of degrader in sediment may be explained by the enhanced root activity due to the elevation in DIN accessibility.

  11. EFFECT OF FLUID SHEAR AND IRRADIANCE ON POPULATION GROWTH AND CELLULAR TOXIN CONTENT OF THE DINOFLAGELLATE ALEXANDRIUM FUNDYENSE.

    EPA Science Inventory

    The potential for in situ turbulence to inhibit dinoflagellate population growth has been demonstrated by experimentally exposing dinoflagellate cultures to quantified shear flow. However, despite interest in understanding environmental factors that affect the growth of toxic din...

  12. 76 FR 46896 - Designation of Six Individuals Pursuant to Executive Order 13224

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-03

    ..., Izz al-Din Abd al-Farid); DOB 1982; POB al-Qamishli, Syria; nationality Syria; ethnicity Kurdish.... ``RAWANSARI, Shahin''); DOB 1967; nationality Syria; alt. nationality Iran; ethnicity Kurdish...

  13. Blessed by the Holy People.

    PubMed

    House, Carrie

    2016-01-01

    Men-women and women-men have a long tradition in Diné (Navajo) culture where they were, and sometimes still are, held in high esteem. Their supernatural prototypes figure prominently in parts of the Diné Origin Story. It is in this cosmological worldview and tradition of acceptance that Carrie, a multi-dualistic spirit, grew up to be a female-bodied man supported and respected by his/her family and community. He/she has worked in various professions defined as "masculine" in Diné and Western contexts, such as fire fighter, heavy equipment operator, truck driver, and building contractor. In addition, Carrie is a keeper of Diné traditions, and has also been active educating Native and Non-Native audiences on 2SpiritLesbianGayBiTransIntersexQueer issues. PMID:27254759

  14. Linking seasonal inorganic nitrogen shift to the dynamics of microbial communities in the Chesapeake Bay.

    PubMed

    Hong, Yiguo; Xu, Xiongrong; Kan, Jinjun; Chen, Feng

    2014-04-01

    Seasonal shifts of dissolved inorganic nitrogen (DIN) and the dynamics of microbial communities for nitrogen transformation were investigated in the water column of Chesapeake Bay. The relative abundance of nitrogen over phosphorus (N) showed a strong seasonal and spatial pattern: gradually decreased from upstream to downstream; high in winter and low in summer. Because the phosphorus concentration remained relatively stable, the spatiotemporal pattern of N implied that a substantial fraction of DIN was removed in the bay, especially in summer. Correlation analyses indicated the functional microbial communities and environmental variables, such as temperature, dissolved oxygen, salinity, played important roles for connecting the seasonal variation of N. Among them, temperature was the trigger factor. High temperature in the summer induced the growth of functional microbes, which subsequently consumed a large portion of DIN inputted from the tributaries and reduced the N. The current study provided the relative importance of microbial communities and environmental variables in driving the DIN loss in the bay.

  15. DISTINGUISHING AND QUANTIFYING NATURAL AND ANTHROPOGENIC NUTRIENT LOADING TO PACIFIC NORTHWEST ESTUARIES

    EPA Science Inventory

    Many coastal ecosystems are experiencing environmental problems due to excess nutrients, particularly nitrogen. Identifying the sources of dissolved inorganic nitrogen (DIN) in estuaries is complicated by the multiple sources and pathways, temporal variability in inputs, and var...

  16. Eutrophication and macroalgal blooms in temperate and tropical coastal waters: nutrient enrichment experiments with Ulva spp.

    PubMed Central

    Teichberg, Mirta; Fox, Sophia E; Olsen, Ylva S; Valiela, Ivan; Martinetto, Paulina; Iribarne, Oscar; Muto, Elizabeti Yuriko; Petti, Monica A V; Corbisier, Thaïs N; Soto-Jiménez, Martín; Páez-Osuna, Federico; Castro, Paula; Freitas, Helena; Zitelli, Andreina; Cardinaletti, Massimo; Tagliapietra, Davide

    2010-01-01

    Receiving coastal waters and estuaries are among the most nutrient-enriched environments on earth, and one of the symptoms of the resulting eutrophication is the proliferation of opportunistic, fast-growing marine seaweeds. Here, we used a widespread macroalga often involved in blooms, Ulva spp., to investigate how supply of nitrogen (N) and phosphorus (P), the two main potential growth-limiting nutrients, influence macroalgal growth in temperate and tropical coastal waters ranging from low- to high-nutrient supplies. We carried out N and P enrichment field experiments on Ulva spp. in seven coastal systems, with one of these systems represented by three different subestuaries, for a total of nine sites. We showed that rate of growth of Ulva spp. was directly correlated to annual dissolved inorganic nitrogen (DIN) concentrations, where growth increased with increasing DIN concentration. Internal N pools of macroalgal fronds were also linked to increased DIN supply, and algal growth rates were tightly coupled to these internal N pools. The increases in DIN appeared to be related to greater inputs of wastewater to these coastal waters as indicated by high δ15N signatures of the algae as DIN increased. N and P enrichment experiments showed that rate of macroalgal growth was controlled by supply of DIN where ambient DIN concentrations were low, and by P where DIN concentrations were higher, regardless of latitude or geographic setting. These results suggest that understanding the basis for macroalgal blooms, and management of these harmful phenomena, will require information as to nutrient sources, and actions to reduce supply of N and P in coastal waters concerned.

  17. Process Models in E-Learning--Bottom-Up or Top-Down?

    ERIC Educational Resources Information Center

    Sahl, Sarah; Martens, Alke

    2015-01-01

    In the paper, different approaches of process modelling in e-learning system development are investigated. We provide a look at the DIN PAS 1032-1 and in the process model ROME, which is a derivation of the DIN PAS 1032-1. ROME has been extended by several pattern approaches. However, after several years of using ROME, we found out that ROME has…

  18. A nitrogen budget for the Strait of Georgia, British Columbia, with emphasis on particulate nitrogen and dissolved inorganic nitrogen

    NASA Astrophysics Data System (ADS)

    Sutton, J. N.; Johannessen, S. C.; Macdonald, R. W.

    2013-11-01

    Balanced budgets for dissolved inorganic N (DIN) and particulate N (PN) were constructed for the Strait of Georgia (SoG), a semi-enclosed coastal sea off the west coast of British Columbia, Canada. The dominant control on the N budget is the advection of DIN into and out of the SoG via Haro Strait. The annual influx of DIN by advection from the Pacific Ocean is 29 990 (±19 500) Mmol yr-1. The DIN flux advected out of the SoG is 24 300 (±15 500) Mmol yr-1. Most of the DIN that enters the SoG (~ 23 400 Mmol yr-1) is converted to particulate N (PN) in situ by primary production. However, most of the PN produced by primary production is remineralized (~ 22 000 Mmol yr-1) back into DIN within the top 50 m. The PN budget for the SoG was further constrained by nitrogen isotope composition (δ15N) that indicated regional differences in the source of PN. The southern strait receives a much higher proportion of terrigenous PN, relative to marine PN, than does the northern strait. The difference is due to the influence of the Fraser River, which discharges 1950 Mmol yr-1 of PN and 1660 Mmol yr-1 of DIN into the southern strait. The overall anthropogenic contribution of PN and DIN to the SoG is minimal relative to natural sources (> 30 000 Mmol yr-1). It is unlikely that the strait will be affected by eutrophication in the near future, although anthropogenic N sources, such as wastewater outfalls, may have significant local effects.

  19. Selection of effective macroalgal species and tracing nitrogen sources on the different part of Yantai coast, China indicated by macroalgal δ(15)N values.

    PubMed

    Wang, Yujue; Liu, Dongyan; Richard, Pierre; Di, Baoping

    2016-01-15

    To determine the dominant nitrogen sources and select effective macroalgal species for monitoring eutrophication along the Yantai coast, the total carbon (TOC), total nitrogen (TN) and nitrogen stable isotope ratio (δ(15)N) in macroalgal tissue were analyzed in conjunction with environmental variables in seawater along the Yantai coastline. The ranges of macroalgal tissue δ(15)N values together with dissolved inorganic nitrogen (DIN) composition indicated that except for the atmospheric deposition, there were three dominant types of nitrogen sources along the Yantai coast, with the agricultural fertilizer usage and factorial wastewater input at the S1 (Zhifu Island coast), the sewage discharge at S2 (the Moon Bay coast), the sewage discharge together with aquaculture impacts at S3 (Fisherman Wharf coast) and S4 (the Horse Island coast). Macroalgal growth were not limited by DIN but limited by P at S2, S3 and S4. Macroalgal species suitable or not for DIN source tracing along the Yantai coast were discussed. For sites with low DIN concentration, many species of three phyla could be used for DIN sources tracing with Laurencia okamurai, Gloiopeltis furcata and Ulva pertusa being ideal species. For site with high DIN concentration, however, species of Rhodophyta were not suitable and only Scytosiphon lomentaria and Monostroma nitidium were chosen.

  20. Selection of effective macroalgal species and tracing nitrogen sources on the different part of Yantai coast, China indicated by macroalgal δ(15)N values.

    PubMed

    Wang, Yujue; Liu, Dongyan; Richard, Pierre; Di, Baoping

    2016-01-15

    To determine the dominant nitrogen sources and select effective macroalgal species for monitoring eutrophication along the Yantai coast, the total carbon (TOC), total nitrogen (TN) and nitrogen stable isotope ratio (δ(15)N) in macroalgal tissue were analyzed in conjunction with environmental variables in seawater along the Yantai coastline. The ranges of macroalgal tissue δ(15)N values together with dissolved inorganic nitrogen (DIN) composition indicated that except for the atmospheric deposition, there were three dominant types of nitrogen sources along the Yantai coast, with the agricultural fertilizer usage and factorial wastewater input at the S1 (Zhifu Island coast), the sewage discharge at S2 (the Moon Bay coast), the sewage discharge together with aquaculture impacts at S3 (Fisherman Wharf coast) and S4 (the Horse Island coast). Macroalgal growth were not limited by DIN but limited by P at S2, S3 and S4. Macroalgal species suitable or not for DIN source tracing along the Yantai coast were discussed. For sites with low DIN concentration, many species of three phyla could be used for DIN sources tracing with Laurencia okamurai, Gloiopeltis furcata and Ulva pertusa being ideal species. For site with high DIN concentration, however, species of Rhodophyta were not suitable and only Scytosiphon lomentaria and Monostroma nitidium were chosen. PMID:26519590

  1. Modeling ocean circulation and biogeochemical variability in the Gulf of Mexico

    NASA Astrophysics Data System (ADS)

    Xue, Z.; He, R.; Fennel, K.; Cai, W.-J.; Lohrenz, S.; Hopkinson, C.

    2013-11-01

    A three-dimensional coupled physical-biogeochemical model is applied to simulate and examine temporal and spatial variability of circulation and biogeochemical cycling in the Gulf of Mexico (GoM). The model is driven by realistic atmospheric forcing, open boundary conditions from a data assimilative global ocean circulation model, and observed freshwater and terrestrial nitrogen input from major rivers. A 7 yr model hindcast (2004-2010) was performed, and validated against satellite observed sea surface height, surface chlorophyll, and in situ observations including coastal sea level, ocean temperature, salinity, and dissolved inorganic nitrogen (DIN) concentration. The model hindcast revealed clear seasonality in DIN, phytoplankton and zooplankton distributions in the GoM. An empirical orthogonal function analysis indicated a phase-locked pattern among DIN, phytoplankton and zooplankton concentrations. The GoM shelf nitrogen budget was also quantified, revealing that on an annual basis the DIN input is largely balanced by the removal through denitrification (an equivalent of ~ 80% of DIN input) and offshore exports to the deep ocean (an equivalent of ~ 17% of DIN input).

  2. FAST TRACK PAPER: An advanced slip model for the Umbria-Marche earthquake sequence: coseismic displacements observed by SAR interferometry and model inversion

    NASA Astrophysics Data System (ADS)

    Crippa, B.; Crosetto, M.; Biescas, E.; Troise, C.; Pingue, F.; de Natale, G.

    2006-01-01

    We report an improved slip model for the 1997 September-October Umbria-Marche earthquake sequence in central Italy. The model is based on coseismic displacements estimated by differential synthetic aperture radar (DInSAR) interferometry using an advanced inverse modelling approach that enables the characteristics of the SAR data, especially their dense spatial sampling, to be fully exploited. The paper first looks at DInSAR analysis using the simplest configuration, that is, a single-image pair that temporally covers the earthquake sequence. Yet, given that this DInSAR configuration is often used for coseismic studies and the limited availability of SAR data, we duly consider the limitations of the DInSAR results and discuss the rigorous DInSAR procedure carried out, highlighting key errors associated with such observations. We then focus on the inversion of the estimated DInSAR displacements and on our advanced heterogeneous slip model for this earthquake sequence's main shocks, emphasizing its most significant features.

  3. Inorganic nitrogen wet deposition: Evidence from the North-South Transect of Eastern China.

    PubMed

    Zhan, X; Yu, G; He, N; Jia, B; Zhou, M; Wang, C; Zhang, J; Zhao, G; Wang, S; Liu, Y; Yan, J

    2015-09-01

    We examined the spatio-temporal variation of dissolved inorganic nitrogen (DIN) deposition in eight typical forest ecosystems of Eastern China for three consecutive years. DIN deposition exhibited an increasing gradient from north to south, with N-NH4(+) as the predominant contributor. DIN deposition in precipitation changed after interaction with the forest canopy, and serious ecological perturbations are expected in this region. DIN deposition presented seasonal fluctuations, which might be ascribed to agricultural activity, fossil-fuel combustion and environmental factors (i.e., wind direction, soil temperature). Notably, N fertilizer use (FN), energy consumption (E), and precipitation (P) jointly explained 84.3% of the spatial variation in DIN deposition, of which FN (27.2%) was the most important, followed by E (24.8%), and finally P (9.3%). The findings demonstrate that DIN deposition is regulated by precipitation mainly via anthropogenic N emissions, and this analysis provides decision-makers a novel view for N pollution abatement. PMID:25898231

  4. Dynamic patterns of dissolved nitrogen in the Southern Bight of the North Sea

    NASA Astrophysics Data System (ADS)

    Baeyens, Willy; Mommaerts, Jean-Paul; Goeyens, Leo; Dehairs, Frank; Dedeurwaerder, Hugues; Decadt, Ghislain

    1984-05-01

    Spatial and temporal variations of dissolved inorganic nitrogen (DIN) have been assessed in onshore and offshore areas of the Southern Bight on the basis of several years' measurements. They indicate that both the residual flow lines and DIN isoconcentration lines run parallel with the coast except in the vicinity of important freshwater discharge points such as the Scheldt estuary. Evidence was found that the seasonal DIN oscillations are not created through fluctuations in input conditions at the lateral boundaries, despite considerable fluctuations in these inputs which include the English Channel (from 500 tons(t) N day -1 in June up to approximately 2000 t N day -1 in February) and also rivers such as the Scheldt estuary (up to 50 t N day -1 in January but less than 5 t N day -1 in June-July). In both the onshore and offshore areas the sum of daylight phytoplanktonic nitrogen intake and sediment release of nitrogen corresponds to the observed DIN variations during most of the year. Pelagic N-mineralization from natural or grazing mortality of phytoplankton (220 mg N m -2 day -1 onshore at its maximum) can account for the differences (200 mg N m -2 day -1 onshore at its maximum), especially at the end of the phytoplankton spring bloom. Although the causes of DIN oscillations onshore and offshore are the same, the results differ because offshore (1) the vegetative season lasts longer, and (2) DIN is exhausted at the end of the phytoplankton spring bloom.

  5. The development of iodine based impinger solutions for the efficient capture of Hg0 using direct injection nebulization-inductively coupled plasma mass spectrometry analysis.

    PubMed

    Hedrick, E; Lee, T G; Biswas, P; Zhuang, Y

    2001-09-15

    Inductively coupled plasma mass spectrometry (ICP/MS) with direct injection nebulization (DIN) was used to evaluate novel impinger solution compositions capable of capturing elemental mercury (Hg0) in EPA Method 5 type sampling. An iodine based impinger solution proved to be very efficient for Hg0 capture and was amenable to direct analysis by DIN-ICP/MS. Hg0 capture efficiency using aqueous iodine (I3-) was comparable to Hg0 capture using acidified potassium permanganate impinger solutions which were analyzed by cold vapor atomic absorption spectrometry (CVAAS), with greater than 98% capture of Hg0 in the first oxidizing impinger. Using DIN-ICP/MS, it was demonstrated for the first time that iodine can be generated just prior to impinger sampling for efficiently oxidizing Hg0 and retaining it in solution as HgI4(2-). Due to the increased interest in Hg speciation from combustion sources and the potential for using DIN-ICP/MS for multiple metals analyses, an impinger sampling train for gaseous Hg speciation and multiple metals analyses using DIN-ICP/MS analyses is presented. The unique feature of such a sampling train is that each impinger solution in the series is amenable to direct analysis by DIN-ICP/MS. A bituminous coal was combusted in a bench scale coal system, and gaseous Hg species (oxidized and elemental) were determined using the proposed impinger train. The DIN-ICP/MS instrumental detection limit was 0.003 ppb, and MDLs ranged from 0.007 to 0.116 microg/L (ppb) in a variety of impinger solutions used for Hg capture.

  6. Variation characteristics of nitrogen concentrations through forest hydrologic subcycles in various forests across mainland China.

    PubMed

    Sun, Suqi; Wang, Yunqi; Wang, Yujie; Zhang, Huilan; Yu, Lei; Liu, Yong; Zhu, Jinqi

    2015-01-01

    Increased anthropogenic nitrogen emissions and more severe environmental issues (e.g. air pollution, soil acidification, and plant nutrient imbalances) are striking forest ecosystems. Data on NH4+ and NO3- concentrations in throughfall and stemflow were collected to estimate variation characteristics of nitrogen concentrations through forest hydrological processes across China. A typical study was carried out in the three forest types in the Jinyun Mountain region of Chongqing, from May to October 2012. Nitrogen concentrations in throughfall and stemflow are higher than those in atmospheric precipitation. DIN concentrations in atmospheric precipitation, throughfall, and stemflow, across China and in the Jinyun Mountain region, were 2.18 and 1.51, 3.19 and 3.88, and 5.14 and 3.92 mg N L(-1), respectively. NH4+ concentration was higher than NO3- concentration, suggesting NH4+ is the dominant nitrogen component in China. Additionally, across China, a linear relationship existed between DIN and NH4+, and between DIN and NO3- in atmospheric precipitation. DIN concentrations in throughfall and stemflow changed with the observed changes in precipitation, and DIN concentrations in precipitation positively correlated with those in throughfall and in stemflow were also observed. Moreover, average DIN concentrations in throughfall and stemflow varied in different forest types, resulting from differences in forest canopy structures and tree species characteristics. In the Jinyun Mountain region, both throughfall and stemflow DIN concentrations were the highest in the mixed broadleaved/coniferous forest, followed by evergreen broadleaved forest, and the lowest in moso bamboo forest. Monthly variations of NH4+ and NO3- concentrations, in throughfall and stemflow, were observed in the Jinyun Mountain region.

  7. Geochemistry of Inorganic Nitrogen in Waters Released from Coal-Bed Natural Gas Production Wells in the Powder River Basin, Wyoming

    USGS Publications Warehouse

    Smith, Richard L.; Repert, Deborah A.; Hart, Charles P.

    2009-01-01

    Water originating from coal-bed natural gas (CBNG) production wells typically contains ammonium and is often disposed via discharge to ephemeral channels. A study conducted in the Powder River Basin, Wyoming, documented downstream changes in CBNG water composition, emphasizing nitrogen-cycling processes and the fate of ammonium. Dissolved ammonium concentrations from 19 CBNG discharge points ranged from 95 to 527 µM. Within specific channels, ammonium concentrations decreased with transport distance, with subsequent increases in nitrite and nitrate concentrations. Removal efficiency, or uptake, of total dissolved inorganic nitrogen (DIN) varied between channel types. DIN uptake was greater in the gentle-sloped, vegetated channel as compared to the incised, steep, and sparsely vegetated channel and was highly correlated with diel patterns of incident light and dissolved oxygen concentration. In a larger main channel with multiple discharge inputs (n = 13), DIN concentrations were >300 µM, with pH > 8.5, after 5 km of transport. Ammonium represented 25-30% of the large-channel DIN, and ammonium concentrations remained relatively constant with time, with only a weak diel pattern evident. In July 2003, the average daily large-channel DIN load was 23 kg N day-1 entering the Powder River, an amount which substantially increased the total Powder River DIN load after the channel confluence. These results suggest that CBNG discharge may be an important source of DIN to western watersheds, at least at certain times of the year, and that net oxidation and/or removal is dependent upon the extent of contact with sediment and biomass, type of drainage channel, and time of day.

  8. Geochemistry of inorganic nitrogen in waters released from coal-bed natural gas production wells in the Powder River Basin, Wyoming.

    PubMed

    Smith, Richard L; Repert, Deborah A; Hart, Charles P

    2009-04-01

    Water originating from coal-bed natural gas (CBNG) production wells typically contains ammonium and is often disposed via discharge to ephemeral channels. A study conducted in the Powder River Basin, Wyoming, documented downstream changes in CBNG water composition, emphasizing nitrogen-cycling processes and the fate of ammonium. Dissolved ammonium concentrations from 19 CBNG discharge points ranged from 95 to 527 microM. Within specific channels, ammonium concentrations decreased with transport distance, with subsequent increases in nitrite and nitrate concentrations. Removal efficiency, or uptake, oftotal dissolved inorganic nitrogen (DIN) varied between channel types. DIN uptake was greater in the gentle-sloped, vegetated channel as compared to the incised, steep, and sparsely vegetated channel and was highly correlated with diel patterns of incident light and dissolved oxygen concentration. In a larger main channel with multiple discharge inputs (n=13), DIN concentrations were >300 microM, with pH > 8.5, after 5 km of transport. Ammonium represented 25-30% of the large-channel DIN, and ammonium concentrations remained relatively constant with time, with only a weak diel pattern evident. In July 2003, the average daily large-channel DIN load was 23 kg N day(-1) entering the Powder River, an amount which substantially increased the total Powder River DIN load after the channel confluence. These results suggest that CBNG discharge may be an important source of DIN to western watersheds, at least at certain times of the year, and that net oxidation and/or removal is dependent upon the extent of contact with sediment and biomass, type of drainage channel, and time of day.

  9. Geochemistry of inorganic nitrogen in waters released from coal-bed natural gas production wells in the powder river basin, wyoming

    USGS Publications Warehouse

    Smith, R.L.; Repert, D.A.; Hart, C.P.

    2009-01-01

    Water originating from coal-bed natural gas (CBNG) production wells typically contains ammonium and is often disposed via discharge to ephemeral channels. A. study conducted in the Powder River Basin, Wyoming, documented downstream changes in CBNG water composition, emphasizing nitrogen-cycling processes and the fate of ammonium. Dissolved ammonium concentrations from 19 CBNG discharge points ranged from 95 to 527 ??M. Within specific channels, ammonium concentrations decreased with transport distance, with subsequent increases in nitrite and nitrate concentrations. Removal efficiency, or uptake, of total dissolved inorganic nitrogen (DIN) varied between channel types. DIN uptake was greater in the gentle-sloped, vegetated channel as compared to the incised, steep, and sparsely vegetated channel and was highly correlated with diel patterns of incident light and dissolved oxygen concentration. In a larger main channel with multiple discharge inputs (n = 13), DIN concentrations were >300 ??M, with pH > 8.5, after 5 km of transport. Ammonium represented 25-30% of the large-channel DIN, and ammonium concentrations remained relatively constant with time, with only a weak diel pattern evident. In July 2003, the average daily large-channel DIN load was 23 kg N day-1 entering the Powder River, an amount which substantially increased the total Powder River DIN load after the channel confluence. These results suggest that CBNG discharge may be an important source of DIN to western watersheds, at least at certain times of the year, and that net oxidation and/or removal is dependent upon the extent of contact with sediment and biomass, type of drainage channel, and time of day. ?? 2009 American Chemical Society.

  10. Toxin YafQ Reduces Escherichia coli Growth at Low Temperatures.

    PubMed

    Zhao, Yueju; McAnulty, Michael J; Wood, Thomas K

    2016-01-01

    Toxin/antitoxin (TA) systems reduce metabolism under stress; for example, toxin YafQ of the YafQ/DinJ Escherichia coli TA system reduces growth by cleaving transcripts with in-frame 5'-AAA-G/A-3' sites, and antitoxin DinJ is a global regulator that represses its locus as well as controls levels of the stationary sigma factor RpoS. Here we investigated the influence on cell growth at various temperatures and found that deletion of the antitoxin gene, dinJ, resulted in both reduced metabolism and slower growth at 18°C but not at 37°C. The reduction in growth could be complemented by producing DinJ from a plasmid. Using a transposon screen to reverse the effect of the absence of DinJ, two mutations were found that inactivated the toxin YafQ; hence, the toxin caused the slower growth only at low temperatures rather than DinJ acting as a global regulator. Corroborating this result, a clean deletion of yafQ in the ΔdinJ ΔKmR strain restored both metabolism and growth at 18°C. In addition, production of YafQ was more toxic at 18°C compared to 37°C. Furthermore, by overproducing all the E. coli proteins, the global transcription repressor Mlc was found that counteracts YafQ toxicity only at 18°C. Therefore, YafQ is more effective at reducing metabolism at low temperatures, and Mlc is its putative target. PMID:27557125

  11. Toxin YafQ Reduces Escherichia coli Growth at Low Temperatures

    PubMed Central

    Zhao, Yueju; McAnulty, Michael J.

    2016-01-01

    Toxin/antitoxin (TA) systems reduce metabolism under stress; for example, toxin YafQ of the YafQ/DinJ Escherichia coli TA system reduces growth by cleaving transcripts with in-frame 5’-AAA-G/A-3’ sites, and antitoxin DinJ is a global regulator that represses its locus as well as controls levels of the stationary sigma factor RpoS. Here we investigated the influence on cell growth at various temperatures and found that deletion of the antitoxin gene, dinJ, resulted in both reduced metabolism and slower growth at 18°C but not at 37°C. The reduction in growth could be complemented by producing DinJ from a plasmid. Using a transposon screen to reverse the effect of the absence of DinJ, two mutations were found that inactivated the toxin YafQ; hence, the toxin caused the slower growth only at low temperatures rather than DinJ acting as a global regulator. Corroborating this result, a clean deletion of yafQ in the ΔdinJ ΔKmR strain restored both metabolism and growth at 18°C. In addition, production of YafQ was more toxic at 18°C compared to 37°C. Furthermore, by overproducing all the E. coli proteins, the global transcription repressor Mlc was found that counteracts YafQ toxicity only at 18°C. Therefore, YafQ is more effective at reducing metabolism at low temperatures, and Mlc is its putative target. PMID:27557125

  12. A Computational Model of a Descending Mechanosensory Pathway Involved in Active Tactile Sensing

    PubMed Central

    Ache, Jan M.; Dürr, Volker

    2015-01-01

    Many animals, including humans, rely on active tactile sensing to explore the environment and negotiate obstacles, especially in the dark. Here, we model a descending neural pathway that mediates short-latency proprioceptive information from a tactile sensor on the head to thoracic neural networks. We studied the nocturnal stick insect Carausius morosus, a model organism for the study of adaptive locomotion, including tactually mediated reaching movements. Like mammals, insects need to move their tactile sensors for probing the environment. Cues about sensor position and motion are therefore crucial for the spatial localization of tactile contacts and the coordination of fast, adaptive motor responses. Our model explains how proprioceptive information about motion and position of the antennae, the main tactile sensors in insects, can be encoded by a single type of mechanosensory afferents. Moreover, it explains how this information is integrated and mediated to thoracic neural networks by a diverse population of descending interneurons (DINs). First, we quantified responses of a DIN population to changes in antennal position, motion and direction of movement. Using principal component (PC) analysis, we find that only two PCs account for a large fraction of the variance in the DIN response properties. We call the two-dimensional space spanned by these PCs ‘coding-space’ because it captures essential features of the entire DIN population. Second, we model the mechanoreceptive input elements of this descending pathway, a population of proprioceptive mechanosensory hairs monitoring deflection of the antennal joints. Finally, we propose a computational framework that can model the response properties of all important DIN types, using the hair field model as its only input. This DIN model is validated by comparison of tuning characteristics, and by mapping the modelled neurons into the two-dimensional coding-space of the real DIN population. This reveals the

  13. A Computational Model of a Descending Mechanosensory Pathway Involved in Active Tactile Sensing.

    PubMed

    Ache, Jan M; Dürr, Volker

    2015-07-01

    Many animals, including humans, rely on active tactile sensing to explore the environment and negotiate obstacles, especially in the dark. Here, we model a descending neural pathway that mediates short-latency proprioceptive information from a tactile sensor on the head to thoracic neural networks. We studied the nocturnal stick insect Carausius morosus, a model organism for the study of adaptive locomotion, including tactually mediated reaching movements. Like mammals, insects need to move their tactile sensors for probing the environment. Cues about sensor position and motion are therefore crucial for the spatial localization of tactile contacts and the coordination of fast, adaptive motor responses. Our model explains how proprioceptive information about motion and position of the antennae, the main tactile sensors in insects, can be encoded by a single type of mechanosensory afferents. Moreover, it explains how this information is integrated and mediated to thoracic neural networks by a diverse population of descending interneurons (DINs). First, we quantified responses of a DIN population to changes in antennal position, motion and direction of movement. Using principal component (PC) analysis, we find that only two PCs account for a large fraction of the variance in the DIN response properties. We call the two-dimensional space spanned by these PCs 'coding-space' because it captures essential features of the entire DIN population. Second, we model the mechanoreceptive input elements of this descending pathway, a population of proprioceptive mechanosensory hairs monitoring deflection of the antennal joints. Finally, we propose a computational framework that can model the response properties of all important DIN types, using the hair field model as its only input. This DIN model is validated by comparison of tuning characteristics, and by mapping the modelled neurons into the two-dimensional coding-space of the real DIN population. This reveals the versatility

  14. Comparison of land-based sources with ambient estuarine concentrations of total dissolved nitrogen in Jiaozhou Bay (China)

    NASA Astrophysics Data System (ADS)

    Lu, Dongliang; Yang, Nannan; Liang, Shengkang; Li, Keqiang; Wang, Xiulin

    2016-10-01

    Seasonal, land-sea synchronous surveys were conducted from 2012 to 2013 to characterize the relationship between the composition of land-based total dissolved nitrogen (TDN) and the concentration of dissolved inorganic nitrogen (DIN) in Jiaozhou Bay (JZB). A total of 11 freshwater riverine sampling sites were selected at the river mouths and at waste water outfalls around JZB, while a total 23 Bay stations were established in JZB. Among them, 11 Bay stations were located near the 11 outfalls. Each land-sea sampling was conducted synchronously during a semi-tidal cycle. The contribution of NO3sbnd N, NO2sbnd N, NH4sbnd N, and dissolved organic nitrogen (DON) to TDN in land-based freshwater were similar to those in JZB seawater, while the contribution of the sum of NO3sbnd N and NO2sbnd N to TDN and the contribution of DON to TDN were about 3.2 and 4.1 times higher than the contribution of NH4sbnd N to TDN, respectively. These results showed that inputs of all land-based forms of nitrogen impact the DIN in seawater. Spatial distributions of DIN and DON, showing a gradual decrease from inner bay to the mouth of the bay, were negatively correlated with S in different seasons. In summer and winter, the ratio of DIN to DON in seawater (Rs) gradually decreased from the inner bay to the center of the bay, and the ratio of land-based DIN to DON (RL) was less than RS, indicating net transformation from land-based DON into marine DIN. However, in spring and autumn, the distribution of Rs was opposite to that in summer and winter, and RL was greater than RS, indicating net conversion from land-based DIN into marine DON. Throughout the whole year, net land-based DON was transformed into marine DIN. We provided direct evidence that the variation in DIN concentration in JZB was affected both by land-based TDN inputs and by their hydrodynamic transport and biogeochemical transformation processes.

  15. Hydrographic conditions during the 2002 SBI process experiments

    NASA Astrophysics Data System (ADS)

    Codispoti, L. A.; Flagg, C.; Kelly, V.; Swift, James H.

    2005-12-01

    A review of the hydrographic data from the 2002 Western Arctic Shelf-Basin Interactions (SBI) Process Cruises permits the following conclusions. (1) Temperature-salinity relationships were similar to canonical descriptions, but at five stations in the outer shelf/slope region, warm/high-salinity Atlantic Layer Water appeared to have risen, displaced the lower halocline, and mixed with shelf/upper halocline water. (2) Primary production in the SBI study region was strongly influenced by the advection of dissolved inorganic nitrogen (DIN) entering via Bering Strait. This import of DIN (ammonium+nitrate+nitrite) is modified by local processes, but without the Bering Strait inflow, biological productivity in the SBI region would be much lower. (3) In comparison to the inflowing Atlantic waters, DIN+urea/phosphate and DIN+urea/silicate ratios in the Pacific waters that dominated the upper ˜150 m of the water column were low. They were also low relative to Redfield uptake ratios for phytoplankton. (4) Microbial processes continue to destroy DIN in significant quantities as the Pacific waters transit the SBI region. (5) Nitrate and ammonium were the principal contributors to DIN. Nitrite concentrations were always <0.4 μM. With a few exceptions urea concentrations were <0.5 μM. (6) Moderate concentrations of DIN occurred in surface layers over the shelf in spring, but surface concentrations in the adjacent basin were low, suggesting that basin productivity is low. (7) In summer, DIN depletion in the surface layers was widespread, but a nutricline below ˜15 m contained chlorophyll and dissolved oxygen maxima suggesting net primary production in this layer. (8) A comparison of nutrient and dissolved oxygen concentrations in abyssal waters of the Canada Basin with conditions in Fram Strait suggests that the deep metabolism in the SBI region is exceedingly low compared to typical deep-ocean values. (9) The low abyssal metabolism and phosphate-silicate relationships

  16. Regulatory role of recF in the SOS response of Escherichia coli: impaired induction of SOS genes by UV irradiation and nalidixic acid in a recF mutant.

    PubMed

    Thoms, B; Wackernagel, W

    1987-04-01

    We isolated a new recF mutant of Escherichia coli K-12 by insertion of transposon Tn5 into the recF gene. This recF400::Tn5 allele displayed the same phenotypic characteristics as the classic recF143 mutation. By using Mu d(Ap lac) fusions, the induction of nine SOS genes, including recA, umuC, dinA, dinB, dinD, dinF, recN, and sulA, by UV irradiation and nalidixic acid was examined. Induction of eight genes by the two agents was impaired by recF400::Tn5 to different extents. The ninth fused SOS gene, dinF, was no longer inducible by UV when combined with recF400::Tn5. The generally impaired SOS response in recF strains did not result from weak induction of recA protein synthesis, since a recA operator-constitutive mutation did not alleviate the inhibitory effect of the recF mutation. The results suggest that recF plays a regulatory role in the SOS response. It is proposed that this role is to optimize the signal usage by recA protein to become a protease. PMID:3031020

  17. A comparison of continuous pneumatic nebulization and flow injection-direction injection nebulization for sample introduction in inductively coupled plasma-mass spectrometry

    SciTech Connect

    Crain, J.S.; Kiely, J.T.

    1997-08-01

    Samples containing Ni, Cd, Pb, and U were analyzed eighteen times over a two-month period using inductively coupled plasma-mass spectrometry (ICP-MS). Sample introduction was accomplished by either flow injection-direct injection nebulization (FI-DIN) or continuous pneumatic nebulization (CPN). Using comparable instrumental measurement procedures, FI-DIN analyses were 33% faster and generated 52% less waste than CPN analyses. Instrumental limits of detection obtained with FI-DIN and CPN were comparable but not equivalent (except in the case of Pb) because of nebulizer-related differences in sensitivity (i.e., signal per unit analyte concentration) and background. Substantial and statistically significant differences were found between FI-DIN and CPN Ni determinations, and in the case of laboratory waste samples, there were also small but statistically significant differences between Cd determinations. These small (2 to 3%) differences were not related to polyatomic ion interference (e.g., {sup 95}Mo{sup 16}O{sup +}), but in light of the time and waste savings to be realized, they should not preclude the use of FI-DIN in place of CPN for determination of Cd, Pb, U, and similar elements present at trace concentrations.

  18. Tools for Iina (Life): the journey of the Iina curriculum to the glittering world.

    PubMed

    Arviso, Vivian; Welle, Dorinda; Todacheene, GloJean; Chee, Janet Slowman; Hale-Showalter, Gloria; Waterhouse, Shirley; John, Susie

    2012-01-01

    This article presents the participatory curriculum development process and foundational Diné (Navajo) concepts that inform the Tools for Iina (Life) curriculum, designed for grades 4-6 by a group of Diné educators to strengthen resiliency by addressing children's health, relationships, identity, and sense of the future, utilizing core concepts from Diné oral tradition. Rather than develop a curriculum relying only on experts, and rather than utilize existing American Indian curricula addressing specific risk behaviors or diseases, we facilitated a dialogue with a range of community members to identify core concepts from Diné oral tradition that could provide young people with a perspective on life and its conflicts and challenges, tools for building respectful and supportive relationships, and stories to inform their sense of themselves, the Diné People, and their shared future. The Ways of Life: Iina Project will make the curriculum available in 2012. We offer reflections for other tribes interested in adopting a similar curriculum development process. PMID:22569728

  19. Variability of the dissolved nutrient (N, P, Si) concentrations in the Bay of Annaba in relation to the inputs of the Seybouse and Mafragh estuaries.

    PubMed

    Ounissi, Makhlouf; Ziouch, Omar-Ramzi; Aounallah, Ouafia

    2014-03-15

    Dissolved inorganic nitrogen (DIN), phosphate (PO₄) and silicic acid (Si(OH)₄) loads from the Seybouse and the Mafragh estuaries into the Bay of Annaba, Algeria, were assessed at three stations of the Bay over three years. The Seybouse inputs had high levels of DIN and PO₄, in contrast to the Mafragh estuary's near-pristine inputs; Si(OH)₄ levels were low in both estuaries. The DIN:PO₄ molar ratios were over 30 in most samples and the Si(OH)4:DIN ratio was less than 0.5 in the Seybouse waters, but nearly balanced in the Mafragh. The specific fluxes of Si-Si(OH)₄ (400-540 kg Si km⁻² yr⁻¹) were comparable in the two catchments, but those of DIN were several-fold higher in the Seybouse (373 kg N km⁻² yr⁻¹). The inner Bay affected by the Seybouse inputs had high levels of all nutrients, while the Mafragh plume and the outer marine station were less enriched.

  20. Net anthropogenic nitrogen inputs (NANI) into the Yangtze River basin and the relationship with riverine nitrogen export

    NASA Astrophysics Data System (ADS)

    Chen, Fei; Hou, Lijun; Liu, Min; Zheng, Yanling; Yin, Guoyu; Lin, Xianbiao; Li, Xiaofei; Zong, Haibo; Deng, Fengyu; Gao, Juan; Jiang, Xiaofen

    2016-02-01

    This study investigated net anthropogenic nitrogen inputs (NANI, including atmospheric nitrogen deposition, nitrogenous fertilizer use, net nitrogen import in food and feed, and agricultural nitrogen fixation) and the associated relationship with riverine dissolved inorganic nitrogen (DIN) export in the Yangtze River basin during the 1980-2012 period. The total NANI in the Yangtze River basin has increased by more than twofold over the past three decades (3537.0 ± 615.3 to 8176.6 ± 1442.1 kg N km-2 yr-1). The application of chemical fertilizer was the largest component of NANI in the basin (51.1%), followed by net nitrogen import in food and feed (26.0%), atmospheric nitrogen deposition (13.2%), and agricultural nitrogen fixation (9.7%). A regression analysis showed that the riverine DIN export was strongly correlated with NANI and the annual water discharge (R2 = 0.90, p < 0.01). NANI in the Yangtze River basin was estimated to contribute 37-66% to the riverine DIN export. We also forecasted future variations in NANI and riverine DIN export for the years 2013 to 2030, based on possible future changes in human activities and the climate. This work provides a quantitative understanding of NANI in the Yangtze River basin and its effects on riverine DIN export and helps to develop integrated watershed nitrogen management strategies.

  1. Downward export of respiratory carbon and dissolved inorganic nitrogen by diel-migrant mesozooplankton at the JGOFS Bermuda time-series station

    NASA Astrophysics Data System (ADS)

    Dam, Hans G.; Roman, Michael R.; Youngbluth, Marsh J.

    1995-07-01

    Published calculations suggest that downward fluxes of respiratory carbon (RC) and dissolved inorganic nitrogen (DIN) associated with diel-migrant zooplankton are significant forms of export production. In this study, we examined variability in downward fluxes of RC and DIN due to diel-migrant mesozooplankton (200-2000 μm) on seven occasions between 25 March and 8 April 1990 at the JGOFS (Joint Global Ocean Flux Study) station off Bermuda. Downward fluxes due to migrators crossing 150 m ranged from 6 to 41 mgC m -2 day -1 (RC) and 2 to 5 mgN m -2 day -1 (DIN). In comparison to gravitational fluxes of POC and PON measured with particle traps at 150m during the same period, mesozooplankton RC flux was 18-70% of POCflux and mesozooplankton DIN flux was 17-82% of PON flux. If the RC and DIN fluxes due to migrators are considered in calculations of export production, the percentage of the production exported below 150 m over the study period would increase by an average of 25% for carbon and 21% for nitrogen. These results support the contention that metabolic activities of diel-migrant zooplankton should be included in calculations of export of carbon and nitrogen out of the mixed layer.

  2. The nutrient, total petroleum hydrocarbon and heavy metal contents in the seawater of Bohai Bay, China: Temporal-spatial variations, sources, pollution statuses, and ecological risks.

    PubMed

    Peng, Shitao

    2015-06-15

    Seawater samples collected between 2007 and 2012 were determined the concentrations of nutrient (DIN and DIP), total petroleum hydrocarbon (TPH), and six different heavy metals (As, Cu, Zn, Pb, Cd and Hg). The DIN, DIP, TPH, Pb, and Cd concentrations decreased from 2007 to 2009 or 2010 and increased after 2010. However, the Hg and Cu concentrations increased from 2007 to 2012. In contrast, the As and Zn gradually decreased during the study period. All of the pollutant concentrations gradually decreased from the shoreline to the offshore sites. PCA result showed that urban and port areas, agriculture, and atmospheric deposition were the main sources of pollutants in the bay. Although most of the pollutants were present at concentrations bellow the highest seawater quality standards in China, eutrophication was a risk in Bohai Bay. In addition, DIN was the main pollutant and was responsible for the eutrophication risk in Bohai Bay.

  3. Responses of phytoplankton community to the input of different aerosols in the East China Sea

    NASA Astrophysics Data System (ADS)

    Meng, X.; Chen, Y.; Wang, B.; Ma, Q. W.; Wang, F. J.

    2016-07-01

    Atmospheric deposition can affect marine phytoplankton by supplying macronutrients and trace elements. We conducted mesocosm experiments by adding aerosols with different composition (dominated by mineral dust, biomass burning and high Cu, and secondary aerosol, respectively) to the surface seawater of the East China Sea. Chlorophyll a concentrations were found to be the highest and lowest after adding aerosols containing the highest Fe and dissolved inorganic nitrogen (DIN), respectively. The relative abundance of Haptophyceae increased significantly after adding mineral dust, whereas diatom, Dinophyceae and Cryptophyceae reached the maximum accompanied with the highest DIN. Our results suggest that Fe may be more important than DIN in promoting primary productivity in the sampled seawater. The input of mineral dust and anthropogenic aerosols may result in distinct changes of phytoplankton community structure.

  4. Modeling increased riverine nitrogen export: Source tracking and integrated watershed-coast management.

    PubMed

    Yu, Dan; Yan, Weijin; Chen, Nengwang; Peng, Benrong; Hong, Huasheng; Zhuo, Guihua

    2015-12-30

    The global NEWS model was calibrated and then used to quantify the long term trend of dissolved inorganic nitrogen (DIN) export from two tributaries of Jiulong River (SE China). Anthropogenic N inputs contributed 61-92% of river DIN yield which increased from 337 in 1980s to 1662 kg N km(-2) yr(-1) in 2000s for the North River, and from 653 to 3097 kg N km(-2) yr(-1) for the West River. North River and West River contributed 55% and 45% respectively of DIN loading to the estuary. Rapid development and poor management driven by national policies were responsible for increasing riverine N export. Scenario analysis and source tracking suggest that reductions of anthropogenic N inputs of at least 30% in the North River (emphasis on fertilizer and manure) and 50% in the West River (emphasis on fertilizer) could significantly improve water quality and mitigate eutrophication in both river and coastal waters. PMID:26517942

  5. MULTISLICE SIMULATION OF TRANSMISSION ELECTRON MICROSCOPY IMAGING OF HELIUM BUBBLES IN IRON

    SciTech Connect

    Yao, Bo; Edwards, Danny J.; Kurtz, Richard J.; Odette, George R.; Yamamoto, Takuya

    2011-04-17

    The objective of this task is to establish the size correlation between transmission electron microscopy (TEM) imaged helium (He) bubbles and the actual bubbles in an iron (Fe) matrix. SUMMARY The results of this simulation study show that the size of TEM imaged He bubbles, represented by the inner diameter of the first dark Fresnel ring under defocused condition (Din), deviated from the actual bubble size (Do). Din was found to be larger than Do when imaged with a highly incoherent electron beam, but smaller than Do if the beam is coherent. The deviation of Din from Do increases with increasing defocus. On the other hand, the electron beam accelerating voltage, bubble size, bubble position, and TEM sample thickness do not significantly affect the value of D0/Do. This study also suggests that He bubbles can be differentiated from argon (Ar) bubbles by differences in Fresnel contrast.

  6. Trend of dissolved inorganic nitrogen at stations downstream from the Three-Gorges Dam of Yangtze River.

    PubMed

    Sun, C C; Shen, Z Y; Xiong, M; Ma, F B; Li, Y Y; Chen, L; Liu, R M

    2013-09-01

    The TRAMO/SEATS program, combined with the Hodrick-Prescott (HP) filter, was used to detect trends and potential change points in time series of dissolved inorganic nitrogen (DIN) at three stations along the Yangtze River. The trend components were extracted, and two change points were successfully detected. The components revealed that DIN has been increasing at all the stations since the 1990s, although variations exist. Changes visible before 2002 illustrate the differences in agriculture development among regions upstream from the stations. The Three-Gorges Dam (TGD), which began to impound in 2003, led to years of different trends. The DIN concentration, which had been trending upward prior to that date, began a slightly downward trend because of NH4(+) depletion. Readings at the Yichang station revealed this trend most strongly; those at the Hankou station less so. The Datong station was far enough away from the TGD so that no obvious effects were seen.

  7. Abiotic effects on effluent dissolved organic nitrogen along an estuarine transect.

    PubMed

    Funkey, Carolina P; Latour, Robert J; Bronk, Deborah A

    2015-03-01

    Biological nutrient removal is a process commonly used in water resource recovery facilities to reduce dissolved inorganic nitrogen (DIN) concentrations in effluent; this process is less effective at removing all of the effluent dissolved organic nitrogen (EDON). The goal of this study was to investigate the fate of EDON after it undergoes the disinfection process and enters receiving waters. The authors quantified the abiotic effects of effluent exposure to sunlight, increased salinity, and a combination of the two factors. Effluent dissolved organic nitrogen showed significant breakdown during the disinfection process (UV and chlorine) and when exposed to sunlight and increasing salinity. Approximately 7% of the EDON was transformed to DIN and dissolved primary amines after exposure to 9 hours of sunlight and a salinity increase from 0 to 33. The production of DIN and primary amines should be taken into account when considering sources of labile nitrogen to aquatic ecosystems.

  8. Capturing the fingerprint of Etna volcano activity in gravity and satellite radar data.

    PubMed

    Del Negro, Ciro; Currenti, Gilda; Solaro, Giuseppe; Greco, Filippo; Pepe, Antonio; Napoli, Rosalba; Pepe, Susi; Casu, Francesco; Sansosti, Eugenio

    2013-10-30

    Long-term and high temporal resolution gravity and deformation data move us toward a better understanding of the behavior of Mt Etna during the June 1995 - December 2011 period in which the volcano exhibited magma charging phases, flank eruptions and summit crater activity. Monthly repeated gravity measurements were coupled with deformation time series using the Differential Synthetic Aperture Radar Interferometry (DInSAR) technique on two sequences of interferograms from ERS/ENVISAT and COSMO-SkyMed satellites. Combining spatiotemporal gravity and DInSAR observations provides the signature of three underlying processes at Etna: (i) magma accumulation in intermediate storage zones, (ii) magmatic intrusions at shallow depth in the South Rift area, and (iii) the seaward sliding of the volcano's eastern flank. Here we demonstrate the strength of the complementary gravity and DInSAR analysis in discerning among different processes and, thus, in detecting deep magma uprising in months to years before the onset of a new Etna eruption.

  9. Trend of dissolved inorganic nitrogen at stations downstream from the Three-Gorges Dam of Yangtze River.

    PubMed

    Sun, C C; Shen, Z Y; Xiong, M; Ma, F B; Li, Y Y; Chen, L; Liu, R M

    2013-09-01

    The TRAMO/SEATS program, combined with the Hodrick-Prescott (HP) filter, was used to detect trends and potential change points in time series of dissolved inorganic nitrogen (DIN) at three stations along the Yangtze River. The trend components were extracted, and two change points were successfully detected. The components revealed that DIN has been increasing at all the stations since the 1990s, although variations exist. Changes visible before 2002 illustrate the differences in agriculture development among regions upstream from the stations. The Three-Gorges Dam (TGD), which began to impound in 2003, led to years of different trends. The DIN concentration, which had been trending upward prior to that date, began a slightly downward trend because of NH4(+) depletion. Readings at the Yichang station revealed this trend most strongly; those at the Hankou station less so. The Datong station was far enough away from the TGD so that no obvious effects were seen. PMID:23727562

  10. Sources, loads and dispersion of dissolved inorganic nutrients in Paranaguá Bay

    NASA Astrophysics Data System (ADS)

    Mizerkowski, Byanka Damian; Hesse, Karl-J.; Ladwig, Norbert; da Costa Machado, Eunice; Rosa, Rodrigo; Araujo, Taiana; Koch, Daniela

    2012-12-01

    The present study focuses on the nutrient sources and gradients in Paranaguá Bay (Southern Brazil), where nutrient inputs are related to losses from fertilizer loading in Paranaguá harbour and the discharge of untreated waste water. The input of dissolved inorganic nutrients to the bay from the harbour and city, as well as from river and atmospheric deposition, amounted to 642 t year-1 DIN-N and 92 t year-1 PO4-P. Harbour losses accounted for 6 % of total DIN-N and 39 % of total PO4-P loads to the bay, whereas sewage inputs from the city were responsible for 21 % and 22 %, respectively. River inputs made up 68 % of DIN-N, mainly in the form of nitrate, and 35 % of PO4-P loads, while atmospheric wet deposition was estimated to be in the order of 5 % of DIN-N and 4 % of PO4-P loads. Local maxima in nutrient levels deriving from highly concentrated sewage discharge were observed in front of the harbour and city of Paranaguá, but the plumes are diluted rapidly due to short residence times. DIN concentrations are negatively correlated with salinity, indicating the importance of freshwater input as a main factor controlling nitrogen distribution. Elevated phosphate levels in the stratified middle section of the bay may result both from harbour emissions and phosphate remobilization from sediments. Generally lower DIN and PO4 concentrations during the warmer rainy season are supposed to be due to intensified assimilation rates especially in the middle section of the bay where dense phytoplankton blooms are observed. The bay as a whole cannot be classified as being seriously eutrophic, albeit eutrophication symptoms prevail in some restricted locations in front of Paranaguá harbour.

  11. Impacts of Labile Organic Carbon Concentration on Organic and Inorganic Nitrogen Utilization by a Stream Biofilm Bacterial Community

    PubMed Central

    Leff, Laura G.

    2013-01-01

    In aquatic ecosystems, carbon (C) availability strongly influences nitrogen (N) dynamics. One manifestation of this linkage is the importance in the dissolved organic matter (DOM) pool of dissolved organic nitrogen (DON), which can serve as both a C and an N source, yet our knowledge of how specific properties of DOM influence N dynamics are limited. To empirically examine the impact of labile DOM on the responses of bacteria to DON and dissolved inorganic nitrogen (DIN), bacterial abundance and community composition were examined in controlled laboratory microcosms subjected to various combinations of dissolved organic carbon (DOC), DON, and DIN treatments. Bacterial communities that had colonized glass beads incubated in a stream were treated with various glucose concentrations and combinations of inorganic and organic N (derived from algal exudate, bacterial protein, and humic matter). The results revealed a strong influence of C availability on bacterial utilization of DON and DIN, with preferential uptake of DON under low C concentrations. Bacterial DON uptake was affected by the concentration and by its chemical nature (labile versus recalcitrant). Labile organic N sources (algal exudate and bacterial protein) were utilized equally well as DIN as an N source, but this was not the case for the recalcitrant humic matter DON treatment. Clear differences in bacterial community composition among treatments were observed based on terminal restriction fragment length polymorphisms (T-RFLP) of 16S rRNA genes. C, DIN, and DON treatments likely drove changes in bacterial community composition that in turn affected the rates of DON and DIN utilization under various C concentrations. PMID:24038688

  12. Sources of nitrogen and phosphorous to northern San Francisco Bay

    USGS Publications Warehouse

    Hager, Stephen W.; Schemel, Laurence E.

    1992-01-01

    We studied nutrient sources to the Sacramento River and Suisun Bay (northern San Francisco Bay) and the influence which these sources have on the distributions of dissolved inorganic nitrogen (DIN) and dissolved reactive phosphorus (DRP) in the river and bay. We found that agricultural return flow drains and a municipal wastewater treatment plant were the largest sources of nutrients to the river during low river flow. The Sutter and Colusa agricultural drains contributed about 70% of the transport of DIN and DRP by the river above Sacramento (about 20% of the total transport by the river) between August 8 and September 26, 1985. Further downstream, the Sacramento Regional Wastewater Treatment Plant discharged DIN and DRP at rates that were roughly 70% of total DIN and DRP transport by the river at that time. Concentrations at Rio Vista on the tidal river below the Sacramento plant and at the head of the estuary were related to the reciprocals of the river flows, indicating the importance of dilution of the Sacramento waste by river flows. During very dry years, elevated DIN and DRP concentrations were observed in Suisun Bay. We used a steady-state, one-dimensional, single-compartment box model of the bay, incorporating terms for advection, exchange, and waste input, to calculate a residual rate for all processes not included in the model. We found that the residual for DIN was related to concentrations of chlorophylla (Chla). The residual for DRP was also related to Chla at high concentrations of Chla, but showed significant losses of DRP at low Chla concentrations. These losses were typically equivalent to about 80% of the wastewater input rate.

  13. Photoaffinity labeling and photoaffinity cross-linking of phosphofructokinase-1 from Saccharomyces cerevisiae by 8-azidoadeninenucleotides.

    PubMed

    Knoche, M; Mönnich, K; Schäfer, H J; Kopperschläger, G

    2001-01-15

    Phosphofructokinase-1 from Saccharomyces cerevisiae is composed of four alpha- and four beta-subunits, each of them carrying catalytic and regulatory bindings sites for MgATP. In this paper, various photoaffinity labels, such as 8-azidoadenosine 5'-triphosphate, 8-azido-1,N6-ethenoadenosine 5'-triphosphate, and 8-N3-3'(2')-O-biotinyl-8-azidoadenosine 5'-triphosphate have been used to study their interaction with the enzyme in the dark and during irradiation. All nucleotidetriphosphates function as phosphate donor forming fructose 1,6-bisphosphate from fructose 6-phosphate. However, the kinetic analysis revealed distinctly differences between them. Photolabeling causes a decrease in enzyme activity to a similar extent, and ATP acts as competitive effector to inactivation. Three bifunctional diazidodiadeninedinucleotides (8-diN3AP4A, monoepsilon-8-diN3AP4A, and diepsilon-8-diN3AP4A) were applied for studying the spatial arrangement of the nucleotide binding sites. No cross-linking of the subunits was obtained by irradiation of the enzyme with 8-diN3AP4A. Photolabeling with diepsilon-8-diN3AP4A resulted in the formation of two alpha-beta cross-links with different mobilities in the SDS-polyacrylamide gel electrophoresis, while monoepsilon-8-diN3AP4A yielded only one alpha-beta cross-link. Because an interfacial location of the catalytic sites between two subunits is less likely, we suggest that the formation of cross-linked subunits may be the result of specific interactions of the bifunctional photolabels with regulatory sites at the interface of both subunits. PMID:11368011

  14. Seasonal dissolved inorganic nitrogen and phosphorus budgets for two sub-tropical estuaries in south Florida, USA

    NASA Astrophysics Data System (ADS)

    Buzzelli, C.; Wan, Y.; Doering, P. H.; Boyer, J. N.

    2013-10-01

    Interactions among geomorphology, circulation, and biogeochemical cycling determine estuary responses to external nutrient loading. In order to better manage watershed nutrient inputs, the goal of this study was to develop seasonal dissolved inorganic nitrogen (DIN) and phosphorus (DIP) budgets for the two estuaries in south Florida, the Caloosahatchee River estuary (CRE) and the St. Lucie Estuary (SLE), from 2002 to 2008. The Land-Ocean Interactions in the Coastal Zone (LOICZ) approach was used to generate water, salt, and DIN and DIP budgets. Results suggested that internal DIN production increases with increased DIN loading to the CRE in the wet season. There were hydrodynamic effects as water column concentrations and ecosystem nutrient processing stabilized in both estuaries as flushing time increased to >10 d. The CRE demonstrated heterotrophy (net ecosystem metabolism or NEM < 0.0) across all wet and dry season budgets. While the SLE was sensitive to DIN loading, system autotrophy (NEM > 0.0) increased significantly with external DIP loading. This included DIP consumption and a bloom of a cyanobacterium (Microcystis aeruginosa) following hurricane-induced discharge to the SLE in 2005. Additionally, while denitrification provided a microbially-mediated N loss pathway for the CRE, this potential was not evident for the SLE where N2 fixation was favored. Disparities between total and inorganic loading ratios suggested that the role of dissolved organic nitrogen (DON) should be assessed for both estuaries. Nutrient budgets indicated that net internal production or consumption of DIN and DIP fluctuated with inter- and intra-annual variations in freshwater inflow, hydrodynamic flushing, and primary production. The results of this study should be included in watershed management plans in order to maintain favorable conditions of external loading relative to internal material cycling in both dry and wet seasons.

  15. Dissolved organic nitrogen budgets for upland, forested ecosystems in New England

    USGS Publications Warehouse

    Campbell, J.L.; Hornbeck, J.W.; McDowell, W.H.; Buso, D.C.; Shanley, J.B.; Likens, G.E.

    2000-01-01

    Relatively high deposition of nitrogen (N) in the northeastern United States has caused concern because sites could become N saturated. In the past, mass-balance studies have been used to monitor the N status of sites and to investigate the impact of increased N deposition. Typically, these efforts have focused on dissolved inorganic forms of N (DIN = NH4-N + NO3-N) and have largely ignored dissolved organic nitrogen (DON) due to difficulties in its analysis. Recent advances in the measurement of total dissolved nitrogen (TDN) have facilitated measurement of DON as the residual of TDN - DIN. We calculated DON and DIN budgets using data on precipitation and streamwater chemistry collected from 9 forested watersheds at 4 sites in New England. TDN in precipitation was composed primarily of DIN. Net retention of TDN ranged from 62 to 89% (4.7 to 10 kg ha-1 yr-1) of annual inputs. DON made up the majority of TDN in stream exports, suggesting that inclusion of DON is critical to assessing N dynamics even in areas with large anthropogenic inputs of DIN. Despite the dominance of DON in streamwater, precipitation inputs of DON were approximately equal to outputs. DON concentrations in streamwater did not appear significantly influenced by seasonal biological controls, but did increase with discharge on some watersheds. Streamwater NO3-N was the only fraction of N that exhibited a seasonal pattern, with concentrations increasing during the winter months and peaking during snowmelt runoff. Concentrations of NO3-N varied considerably among watersheds and are related to DOC:DON ratios in streamwater. Annual DIN exports were negatively correlated with streamwater DOC:DON ratios, indicating that these ratios might be a useful index of N status of upland forests.

  16. Sources of nitrogen and phosphorus to Northern San Francisco Bay

    USGS Publications Warehouse

    Hager, S.W.; Schemel, L.E.

    1992-01-01

    We studied nutrient sources to the Sacramento River and Suisun Bay (northern San Francisco Bay) and the influence which these sources have on the distributions of dissolved inorganic nitrogen (DIN) and dissolved reactive phosphorus (DRP) in the river and bay. We found that agricultural return flow drains and a municipal wastewater treatment plant were the largest sources of nutrients to the river during low river flow. The Sutter and Colusa agricultural drains contributed about 70% of the transport of DIN and DRP by the river above Sacramento (about 20% of the total transport by the river) between August 8 and September 26, 1985. Further downstream, the Sacramento Regional Wastewater Treatment Plant discharged DIN and DRP at rates that were roughly 70% of total DIN and DRP transport by the river at that time. Concentrations at Rio Vista on the tidal river below the Sacramento plant and at the head of the estuary were related to the reciprocals of the river flows, indicating the importance of dilution of the Sacramento waste by river flows. During very dry years, elevated DIN and DRP concentrations were observed in Suisun Bay. We used a steady-state, one-dimensional, single-compartment box model of the bay, incorporating terms for advection, exchange, and waste input, to calculate a residual rate for all processes not included in the model. We found that the residual for DIN was related to concentrations of chlorophyll a (Chl a). The residual for DRP was also related to Chl a at high concentrations of Chl a, but showed significant losses of DRP at low Chl a concentrations. These losses were typically equivalent to about 80% of the wastewater input rate. *** DIRECT SUPPORT *** A01BY057 00004 ?? 1992 Estuarine Research Federation.

  17. Effects of nitrate and phosphate supply on chromophoric and fluorescent dissolved organic matter in the Eastern Tropical North Atlantic: a mesocosm study

    NASA Astrophysics Data System (ADS)

    Loginova, A. N.; Borchard, C.; Meyer, J.; Hauss, H.; Kiko, R.; Engel, A.

    2015-12-01

    In open-ocean regions, as is the Eastern Tropical North Atlantic (ETNA), pelagic production is the main source of dissolved organic matter (DOM) and is affected by dissolved inorganic nitrogen (DIN) and phosphorus (DIP) concentrations. Changes in pelagic production under nutrient amendments were shown to also modify DOM quantity and quality. However, little information is available about the effects of nutrient variability on chromophoric (CDOM) and fluorescent (FDOM) DOM dynamics. Here we present results from two mesocosm experiments ("Varied P" and "Varied N") conducted with a natural plankton community from the ETNA, where the effects of DIP and DIN supply on DOM optical properties were studied. CDOM accumulated proportionally to phytoplankton biomass during the experiments. Spectral slope (S) decreased over time indicating accumulation of high molecular weight DOM. In Varied N, an additional CDOM portion, as a result of bacterial DOM reworking, was determined. It increased the CDOM fraction in DOC proportionally to the supplied DIN. The humic-like FDOM component (Comp.1) was produced by bacteria proportionally to DIN supply. The protein-like FDOM component (Comp.2) was released irrespectively to phytoplankton or bacterial biomass, but depended on DIP and DIN concentrations. Under high DIN supply, Comp.2 was removed by bacterial reworking, leading to an accumulation of humic-like Comp.1. No influence of nutrient availability on amino acid-like FDOM component in peptide form (Comp.3) was observed. Comp.3 potentially acted as an intermediate product during formation or degradation of Comp.2. Our findings suggest that changes in nutrient concentrations may lead to substantial responses in the quantity and quality of optically active DOM and, therefore, might bias results of the applied in situ optical techniques for an estimation of DOC concentrations in open-ocean regions.

  18. Modeling and forecasting riverine dissolved inorganic nitrogen export using anthropogenic nitrogen inputs, hydroclimate, and land-use change

    NASA Astrophysics Data System (ADS)

    Huang, Hong; Chen, Dingjiang; Zhang, Baifa; Zeng, Lingzao; Dahlgren, Randy A.

    2014-09-01

    A quantitative understanding of riverine nitrogen (N) export in response to human activities and climate change is critical for developing effective watershed N pollution control measures. This study quantified net anthropogenic N inputs (NANI) and riverine dissolved inorganic N (DIN = NO3-N + NH4-N + NO2-N) export for the upper Jiaojiang River catchment in eastern China over the 1980-2010 time period and examined how NANI, hydroclimate, and land-use practices influenced riverine DIN export. Over the 31-yr study period, riverine DIN yield increased by 1.6-fold, which mainly results from a ∼77% increase in NANI and increasing fractional delivery of NANI due to a ∼55% increase in developed land area. An empirical model that utilizes an exponential function of NANI and a power function of combining annual water discharge and developed land area percentage could account for 89% of the variation in annual riverine DIN yields in 1980-2010. Applying this model, annual NANI, catchment storage, and natural background sources were estimated to contribute 57%, 22%, and 21%, respectively, of annual riverine DIN exports on average. Forecasting based on a likely future climate change scenario predicted a 19.6% increase in riverine DIN yield by 2030 due to a 4% increase in annual discharge with no changes in NANI and land-use compared to the 2000-2010 baseline condition. Anthropogenic activities have increased both the N inputs available for export and the fractional export of N inputs, while climate change can further enhance riverine N export. An integrated N management strategy that considers the influence of anthropogenic N inputs, land-use and climate change is required to effectively control N inputs to coastal areas.

  19. Leaching characteristics of selected South African fly ashes: Effect of pH on the release of major and trace species

    SciTech Connect

    Gitari, W.M.; Fatoba, O.O.; Petrik, L.F.; Vadapalli, V.R.K.

    2009-07-01

    Fly ash samples from two South African coal-fired power stations were subjected to different leaching tests under alkaline and acidic conditions in an attempt to assess the effect of pH on the leachability of species from the fly ashes and also assess the potential impact of the fly ashes disposal on groundwater and the receiving environment. To achieve this, German Standard leaching (DIN-S4) and Acid Neutralization Capacity (ANC) tests were employed. Ca, Mg, Na, K and SO{sub 4} were significantly leached into solution under the two leaching conditions with the total amounts in ANC leachates higher than that of DIN-S4. This indicates that a large fraction of the soluble salts in unweathered fly ash are easily leached. These species represents the fraction that can be flushed off initially from the surface of ash particles on contacting the ash with water. The amounts of toxic trace elements such as As, Se, Cd, Cr and Pb leached out of the fly ashes when in contact with de-mineralized water (DIN-S4 test) were low and below the Target Water Quality Range (TWQR) of South Africa. This is explained by their low concentrations in the fly ashes and their solubility dependence on the pH of the leaching solution. However the amounts of some minor elements such as B, Mn, Fe, As and Se leached out at lower pH ranging between 10 to 4 (ANC test) were slightly higher than the TWQR, an indication that the pH of the leaching solution plays a significant role on the leaching of species in fly ash. The high concentrations of the toxic elements released from the fly ashes at lower pH gives an indication that the disposal of the fly ash could have adverse effects on the receiving environment if the pH of the solution contacting the ashes is not properly monitored.

  20. Changes in Nitrogen to Phosphorus ratio in the Inner Saronikos Gulf (West Aegean Sea) in relation to the operation of the Sewage Treatment Plant of Athens, Greece

    NASA Astrophysics Data System (ADS)

    Psyllidou-Giouranovits, Rosa

    2013-04-01

    In this work we provide an overview of nitrogen (N) to phosphorus (P) ratio in the inner Saronikos gulf as it has changed over the last twenty five (25) years in relation to the sewage discharges from the Sewage Treatment Plant of Athens in Psittalia Island. Saronikos gulf receives effluents from Athens Metropolitan area (population over 5 million). Until 1994, domestic and industrial sewage of Athens was discharged untreated into the surface water layer of Keratsini and Elefsis bay, whereas, after 1994, the sewage of the Athens Metropolitan area were primarily treated in Psitallia Sewage Treatment Plant and discharged in the inner Saronikos Gulf. Additionally, the secondary stage of the Psittalia Sewage Plant operated in the end of 2004 affecting the nitrogen to phosphorus (DIN:P) ratio (DIN stands for nitrate+nitrite+ammonium). The treated effluent plume frorm Psittalia Sewage Treatment Plant is trapped within the seasonal pycnocline developed during May-November, whereas, during the mixing period (December-April) it reaches the sea-surface. During the last 25 years, significant temporal variation of nutrient concentrations has been observed which has revealed an increase of the DIN:P ratio near the Psittalia Sewage Treatment Plant. In the vicinity of the sewage outfall in Psittalia, DIN:P ratio in the deep layer (30m-bottom) did not show significant variation between the two periods: before and after the operation of the Sewage Treatment Plant (12.9 before the operation of the sewage treatment and 13.3 after the operation of the sewage treatment) showing that inorganic nitrogen and phosphate changed almost with the same rate. However, the limiting factor for phytoplankton growth remains nitrogen. On the contrary, significant increase of DIN:P ratio was observed in the surface layer between the two periods, during summer (stratified period). DIN:P increased from 5.9 for the period 1987-1995 (before the Sewage Treatment Plant operation) to 19.6 for the period 1995

  1. Mechanisms of basin-scale nitrogen load reductions under intensified irrigated agriculture.

    PubMed

    Törnqvist, Rebecka; Jarsjö, Jerker; Thorslund, Josefin; Rao, P Suresh C; Basu, Nandita B; Destouni, Georgia

    2015-01-01

    Irrigated agriculture can modify the cycling and transport of nitrogen (N), due to associated water diversions, water losses, and changes in transport flow-paths. We investigate dominant processes behind observed long-term changes in dissolved inorganic nitrogen (DIN) concentrations and loads of the extensive (465,000 km2) semi-arid Amu Darya River basin (ADRB) in Central Asia. We specifically considered a 40-year period (1960-2000) of large irrigation expansion, reduced river water flows, increased fertilizer application and net increase of N input into the soil-water system. Results showed that observed decreases in riverine DIN concentration near the Aral Sea outlet of ADRB primarily were due to increased recirculation of irrigation water, which extends the flow-path lengths and enhances N attenuation. The observed DIN concentrations matched a developed analytical relation between concentration attenuation and recirculation ratio, showing that a fourfold increase in basin-scale recirculation can increase DIN attenuation from 85 to 99%. Such effects have previously only been observed at small scales, in laboratory experiments and at individual agricultural plots. These results imply that increased recirculation can have contributed to observed increases in N attenuation in agriculturally dominated drainage basins in different parts of the world. Additionally, it can be important for basin scale attenuation of other pollutants, including phosphorous, metals and organic matter. A six-fold lower DIN export from ADRB during the period 1981-2000, compared to the period 1960-1980, was due to the combined result of drastic river flow reduction of almost 70%, and decreased DIN concentrations at the basin outlet. Several arid and semi-arid regions around the world are projected to undergo similar reductions in discharge as the ADRB due to climate change and agricultural intensification, and may therefore undergo comparable shifts in DIN export as shown here for the ADRB

  2. Freshwater and Saline Loads of Dissolved Inorganic Nitrogen to Hood Canal and Lynch Cove, Western Washington

    USGS Publications Warehouse

    Paulson, Anthony J.; Konrad, Christopher P.; Frans, Lonna M.; Noble, Marlene; Kendall, Carol; Josberger, Edward G.; Huffman, Raegan L.; Olsen, Theresa D.

    2006-01-01

    Hood Canal is a long (110 kilometers), deep (175 meters) and narrow (2 to 4 kilometers wide) fjord of Puget Sound in western Washington. The stratification of a less dense, fresh upper layer of the water column causes the cold, saltier lower layer of the water column to be isolated from the atmosphere in the late summer and autumn, which limits reaeration of the lower layer. In the upper layer of Hood Canal, the production of organic matter that settles and consumes dissolved oxygen in the lower layer appears to be limited by the load of dissolved inorganic nitrogen (DIN): nitrate, nitrite, and ammonia. Freshwater and saline loads of DIN to Hood Canal were estimated from available historical data. The freshwater load of DIN to the upper layer of Hood Canal, which could be taken up by phytoplankton, came mostly from surface and ground water from subbasins, which accounts for 92 percent of total load of DIN to the upper layer of Hood Canal. Although DIN in rain falling on land surfaces amounts to about one-half of the DIN entering Hood Canal from subbasins, rain falling directly on the surface of marine waters contributed only 4 percent of the load to the upper layer. Point-source discharges and subsurface flow from shallow shoreline septic systems contributed less than 4 percent of the DIN load to the upper layer. DIN in saline water flowing over the sill into Hood Canal from Admiralty Inlet was at least 17 times the total load to the upper layer of Hood Canal. In September and October 2004, field data were collected to estimate DIN loads to Lynch Cove - the most inland marine waters of Hood Canal that routinely contain low dissolved-oxygen waters. Based on measured streamflow and DIN concentrations, surface discharge was estimated to have contributed about one-fourth of DIN loads to the upper layer of Lynch Cove. Ground-water flow from subbasins was estimated to have contributed about one-half of total DIN loads to the upper layer. In autumn 2004, the relative

  3. Mechanisms of basin-scale nitrogen load reductions under intensified irrigated agriculture.

    PubMed

    Törnqvist, Rebecka; Jarsjö, Jerker; Thorslund, Josefin; Rao, P Suresh C; Basu, Nandita B; Destouni, Georgia

    2015-01-01

    Irrigated agriculture can modify the cycling and transport of nitrogen (N), due to associated water diversions, water losses, and changes in transport flow-paths. We investigate dominant processes behind observed long-term changes in dissolved inorganic nitrogen (DIN) concentrations and loads of the extensive (465,000 km2) semi-arid Amu Darya River basin (ADRB) in Central Asia. We specifically considered a 40-year period (1960-2000) of large irrigation expansion, reduced river water flows, increased fertilizer application and net increase of N input into the soil-water system. Results showed that observed decreases in riverine DIN concentration near the Aral Sea outlet of ADRB primarily were due to increased recirculation of irrigation water, which extends the flow-path lengths and enhances N attenuation. The observed DIN concentrations matched a developed analytical relation between concentration attenuation and recirculation ratio, showing that a fourfold increase in basin-scale recirculation can increase DIN attenuation from 85 to 99%. Such effects have previously only been observed at small scales, in laboratory experiments and at individual agricultural plots. These results imply that increased recirculation can have contributed to observed increases in N attenuation in agriculturally dominated drainage basins in different parts of the world. Additionally, it can be important for basin scale attenuation of other pollutants, including phosphorous, metals and organic matter. A six-fold lower DIN export from ADRB during the period 1981-2000, compared to the period 1960-1980, was due to the combined result of drastic river flow reduction of almost 70%, and decreased DIN concentrations at the basin outlet. Several arid and semi-arid regions around the world are projected to undergo similar reductions in discharge as the ADRB due to climate change and agricultural intensification, and may therefore undergo comparable shifts in DIN export as shown here for the ADRB

  4. Moisture-dependent frictional and aerodynamic properties of safflower seeds

    NASA Astrophysics Data System (ADS)

    Kara, M.; Bastaban, S.; Öztürk, I.; Kalkan, F.; Yildiz, C.

    2012-04-01

    The seeds of two safflower cultivars were investigated in order to determine their frictional and aerodynamic properties as a function of moisture content. The coefficients of dynamic friction of cultivars on aluminium, plywood, fibreglass and steel surfaces increased by 87, 56, 78, and 129% for cv. Remzibey-05 seed, and by 91, 31, 71, and 131% for cv. Dinçer seed, respectively, between the initial and final moisture content levels. The terminal velocities of the Remzibey-05 and Dinçer seeds increased by 15 and 11%, respectively, with increase in moisture content between the initial and final levels.

  5. Quantification and characterization of dissolved organic nitrogen in wastewater effluents by electrodialysis treatment followed by size-exclusion chromatography with nitrogen detection.

    PubMed

    Chon, Kangmin; Lee, Yunho; Traber, Jacqueline; von Gunten, Urs

    2013-09-15

    Dissolved organic nitrogen (DON) can act as a precursor of nitrogenous disinfection byproducts during oxidative water treatment. Quantification and characterization of DON are still challenging for waters with high concentrations of dissolved inorganic nitrogen (DIN, including ammonia, nitrate and nitrite) relative to total dissolved nitrogen (TDN) due to the cumulative analytical errors of independently measured nitrogen species (i.e., DON = TDN - NO2(-) - NO3(-) - NH4(+)/NH3) and interference of DIN species to TDN quantification. In this study, a novel electrodialysis (ED)-based treatment for selective DIN removal was developed and optimized with respect to type of ion-exchange membrane, sample pH, and ED duration. The optimized ED method was then coupled with size-exclusion chromatography with organic carbon, UV, and nitrogen detection (SEC-OCD-ND) for advanced DON analysis in wastewater effluents. Among the tested ion-exchange membranes, the PC-AR anion- and CMT cation-exchange membranes showed the lowest DOC loss (1-7%) during ED treatment of a wastewater effluent at ambient pH (8.0). A good correlation was found between the decrease of the DIN/TDN ratio and conductivity. Therefore, conductivity has been adopted as a convenient way to determine the optimal duration of the ED treatment. In the pH range of 7.0-8.3, ED treatment of various wastewater effluents with the PC-AR/CMT membranes showed that the relative residual conductivity could be reduced to less than 0.50 (DIN removal >90%; DIN/TDN ratio ≤ 0.60) with lower DOC losses (6%) than the previous dialysis and nanofiltration methods (DOC loss >10%). In addition, the ED method is shorter (0.5 h) than the previous methods (>1-24 h). The relative residual conductivity was further reduced to ≈ 0.20 (DIN removal >95%; DIN/TDN ratio ≤ 0.35) by increasing the ED duration to 0.7 h (DOC loss = 8%) for analysis by SEC-OCD-ND, which provided new information on distribution and ratio of organic carbon and

  6. Mechanisms of Basin-Scale Nitrogen Load Reductions under Intensified Irrigated Agriculture

    PubMed Central

    Törnqvist, Rebecka; Jarsjö, Jerker; Thorslund, Josefin; Rao, P. Suresh C.; Basu, Nandita B.; Destouni, Georgia

    2015-01-01

    Irrigated agriculture can modify the cycling and transport of nitrogen (N), due to associated water diversions, water losses, and changes in transport flow-paths. We investigate dominant processes behind observed long-term changes in dissolved inorganic nitrogen (DIN) concentrations and loads of the extensive (465,000 km2) semi-arid Amu Darya River basin (ADRB) in Central Asia. We specifically considered a 40-year period (1960–2000) of large irrigation expansion, reduced river water flows, increased fertilizer application and net increase of N input into the soil-water system. Results showed that observed decreases in riverine DIN concentration near the Aral Sea outlet of ADRB primarily were due to increased recirculation of irrigation water, which extends the flow-path lengths and enhances N attenuation. The observed DIN concentrations matched a developed analytical relation between concentration attenuation and recirculation ratio, showing that a fourfold increase in basin-scale recirculation can increase DIN attenuation from 85 to 99%. Such effects have previously only been observed at small scales, in laboratory experiments and at individual agricultural plots. These results imply that increased recirculation can have contributed to observed increases in N attenuation in agriculturally dominated drainage basins in different parts of the world. Additionally, it can be important for basin scale attenuation of other pollutants, including phosphorous, metals and organic matter. A six-fold lower DIN export from ADRB during the period 1981–2000, compared to the period 1960–1980, was due to the combined result of drastic river flow reduction of almost 70%, and decreased DIN concentrations at the basin outlet. Several arid and semi-arid regions around the world are projected to undergo similar reductions in discharge as the ADRB due to climate change and agricultural intensification, and may therefore undergo comparable shifts in DIN export as shown here for the

  7. Macroalgae δ15N values in well-mixed estuaries: Indicator of anthropogenic nitrogen input or macroalgae metabolism?

    NASA Astrophysics Data System (ADS)

    Raimonet, Mélanie; Guillou, Gaël; Mornet, Françoise; Richard, Pierre

    2013-03-01

    Although nitrogen stable isotope ratio (δ15N) in macroalgae is widely used as a bioindicator of anthropogenic nitrogen inputs to the coastal zone, recent studies suggest the possible role of macroalgae metabolism in δ15N variability. Simultaneous determinations of δ15N of dissolved inorganic nitrogen (DIN) along the land-sea continuum, inter-species variability of δ15N and its sensitivity to environmental factors are necessary to confirm the efficiency of macroalgae δ15N in monitoring nitrogen origin in mixed-use watersheds. In this study, δ15N of annual and perennial macroalgae (Ulva sp., Enteromorpha sp., Fucus vesiculosus and Fucus serratus) are compared to δ15N-DIN along the Charente Estuary, after characterizing δ15N of the three main DIN sources (i.e. cultivated area, pasture, sewage treatment plant outlet). During late winter and spring, when human activities produce high DIN inputs, DIN sources exhibit distinct δ15N signals in nitrate (NO) and ammonium (NH): cultivated area (+6.5 ± 0.6‰ and +9.0 ± 11.0‰), pasture (+9.2 ± 1.8‰ and +12.4‰) and sewage treatment plant discharge (+16.9 ± 8.7‰ and +25.4 ± 5.9‰). While sources show distinct δN- in this multiple source catchment, the overall mixture of NO sources - generally >95% DIN - leads to low variations of δN-NO at the mouth of the estuary (+7.7 to +8.4‰). Even if estuarine δN-NO values are not significantly different from pristine continental and oceanic site (+7.3‰ and +7.4‰), macroalgae δ15N values are generally higher at the mouth of the estuary. This highlights high anthropogenic DIN inputs in the estuary, and enhanced contribution of 15N-depleted NH in oceanic waters. Although seasonal variations in δN-NO are low, the same temporal trends in macroalgae δ15N values at estuarine and oceanic sites, and inter-species differences in δ15N values, suggest that macroalgae δ15N values might be modified by the metabolic response of macroalgae to environmental parameters (e

  8. Reimagining Reading: Creating a Classroom Culture That Embraces Independent Choice Reading

    ERIC Educational Resources Information Center

    Dickerson, Katie

    2015-01-01

    Many of us are plagued by negative memories of sustained silent reading. In some of these memories, we are the students, attempting to read a book that didn't hold our interest or trying to read over the din of our disengaged classmates. In other memories, we are the teachers, suffering through a ten-minute classroom management nightmare, deciding…

  9. 3 CFR 8785 - Proclamation 8785 of March 19, 2012. National Day of Honor

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... years ago, members of the United States Armed Forces crossed the sands of the Iraq-Kuwait border and... din and the fog of war, they never lost their resolve. Demonstrating unshakable fortitude and... Nation’s longest wars, veterans of Operation Iraqi Freedom and Operation New Dawn wrote one of the...

  10. CAPILLARY ELECTROPHORESIS COUPLED ON-LINE WITH INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY FOR ELEMENTAL SPECIATION

    EPA Science Inventory

    A novel interface to connect a capillary electrophoresis (CE) system with an inductively coupled plasma mass spectrometric (ICPMS) detector is reported here. The interface was built using a direct injection nebulizer (DIN) system. In this interface, the CE capillary was placed co...

  11. INPUT-OUTPUT BUDGETS OF INORGANIC NITROGEN FOR 24 FOREST WATERSHEDS IN THE NORTHEASTERN UNITED STATES: A REVIEW

    EPA Science Inventory

    Input-output budgets for dissolved inorganic nitrogen (DIN) are summarized for 24 small watersheds at 15 locations in the northeasternUnited States. The study watersheds are completely forested, free of recent physical disturbances, and span a geographical region bounded by West ...

  12. REGIONAL ANALYSIS OF INORGANIC NITROGEN YIELD AND RETENTION IN HIGH-ELEVATION ECOSYSTEMS OF THE SIERRA NEVADA AND ROCKY MOUNTAINS

    EPA Science Inventory

    Yields and retention of inorganic nitrogen (DIN) and nitrate concentrations in surface runoff are summarized for 28 high elevation watersheds in the Sierra Nevada, California and Rocky Mountains of Wyoming and Colorado. Catchments ranged in elevation from 2475 to 3603 m and from...

  13. THE DEVELOPMENT OF IODINE BASED IMPINGER SOLUTIONS FOR THE EFFICIENT CAPTURE OF HG USING DIRECT INJECTION NEBULIZATION - INDUCTIVELY COUPLED PLASMA MASS SPECTROMETRY ANALYSIS

    EPA Science Inventory

    Inductively coupled plasma mass spectrometry (ICP/MS) with direct injection nebulization (DIN) was used to evaluate novel impinger solution compositions capable of capturing elemental mercury (Hgo) in EPA Method 5 type sampling. An iodine based impinger solutoin proved to be ver...

  14. Factors influencing export of dissolved inorganic nitrogen by major rivers: a new seasonal, spatially explicit, global model

    EPA Science Inventory

    Background/Question/Methods Substantial effort has focused on understanding spatial variation in dissolved inorganic nitrogen (DIN) export to the coastal zone and specific basins have been studied in some depth. Much less is known, however, about seasonal patterns and controls ...

  15. Mass balances of mercury and nitrogen in burned and unburned forested watersheds at Acadia National Park, Maine, USA.

    PubMed

    Nelson, S J; Johnson, K B; Kahl, J S; Haines, T A; Fernandez, I J

    2007-03-01

    Precipitation and streamwater samples were collected from 16 November 1999 to 17 November 2000 in two watersheds at Acadia National Park, Maine, and analyzed for mercury (Hg) and dissolved inorganic nitrogen (DIN, nitrate plus ammonium). Cadillac Brook watershed burned in a 1947 fire that destroyed vegetation and soil organic matter. We hypothesized that Hg deposition would be higher at Hadlock Brook (the reference watershed, 10.2 microg/m(2)/year) than Cadillac (9.4 microg/m(2)/year) because of the greater scavenging efficiency of the softwood vegetation in Hadlock. We also hypothesized the Hg and DIN export from Cadillac Brook would be lower than Hadlock Brook because of elemental volatilization during the fire, along with subsequently lower rates of atmospheric deposition in a watershed with abundant bare soil and bedrock, and regenerating vegetation. Consistent with these hypotheses, Hg export was lower from Cadillac Brook watershed (0.4 microg/m(2)/year) than from Hadlock Brook watershed (1.3 microg/m(2)/year). DIN export from Cadillac Brook (11.5 eq/ha/year) was lower than Hadlock Brook (92.5 eq/ha/year). These data show that approximately 50 years following a wildfire there was lower atmospheric deposition due to changes in forest species composition, lower soil pools, and greater ecosystem retention for both Hg and DIN.

  16. Challenging Texts: Teaching Deliberately--Reading Henry David Thoreau's "Walden"

    ERIC Educational Resources Information Center

    Davis, Andrea

    2011-01-01

    One of the more difficult 19th-century American texts for high school students to read is undoubtedly Henry David Thoreau's "Walden." His erudite allusions, often page-long sentences, and sophisticated sense of the ironic initially leave many students cold. Still, the author encourages them to read amid the din of a cultural cacophony that shouts…

  17. Beneath the Surface.

    ERIC Educational Resources Information Center

    Cohen, Andrew

    1998-01-01

    Discusses wood-flooring components for athletic facilities, what materials make up these floors, and how they affect a floor's performance once installed. The pros and cons of anchored versus floating systems are examined, including the issue of moisture resistance. Also discussed is the influence of Deutsches Institut fur Normans (DIN) standards…

  18. The microbial food web in the Doñana marshland: Influence of trophic state and hydrology

    NASA Astrophysics Data System (ADS)

    Àvila, Núria; López-Flores, Rocío; Quintana, Xavier D.; Serrano, Laura

    2016-10-01

    We investigated the composition of the microbial food web in the marshland of Doñana National Park (SW Spain). We analysed factors affecting the predominance of autotrophic (A) or heterotrophic (H) microorganisms in a set of 16 marshland water bodies that differ in their hydrological pattern. Autotrophic organisms were predominant in the Doñana marshland, with autotrophs between 0.3 and 25.3 times higher than heterotrophs in biomass. The variance partitioning analysis using the log A:H biomass ratio (A/H) as a response variable revealed that water body spatial position accounted for the largest portion of total variance (16% of unique effects), followed by environmental variables (13%), with a shared variation of 24%. Zooplankton biomass had no significant influence on A/H ratio. The two first axes of RDA analysis were related to soluble reactive phosphate (SRP) and dissolved inorganic nitrogen (DIN) concentrations respectively. Cyanobacteria were predominant in waters with high SRP, while other organisms were distributed in relation to DIN by their size, with small organisms predominating with low DIN and large ones with high DIN. Spatial effects reflect the importance of location with respect to the water source in this marshland, where flooding areas are very much dominated by autotrophs, while confined areas, which are a long way from nutrient sources, have a more balanced abundance of autotrophs and heterotrophs.

  19. Variability Associated with As in Vivo–in Vitro Correlations When Using Different Bioaccessibility Methodologies

    EPA Science Inventory

    To evaluate the capabilities of in vitro assays to predict arsenic (As) relative bioavailability (RBA), we examined the relationship between As bioaccessibility, determined using a number of in vitro bioaccessibility (IVBA) methodologies (SBRC, IVG, PBET, DIN and UBM) and As RBA ...

  20. Functional characterization of two toxin-antitoxin systems of Xylella fastidiosa

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Xylella fastidiosa (Xf) encodes multiple toxin-antitoxin (TA) system homologues, including relE/dinJ and mqsR/ygiT. Phylogenetic analyses indicate these two Xf TA systems have distinct evolutionary histories. Comparisons among Xf subspecies/strains reveal TA systems are often embedded in prophage ...

  1. THE RELATIVE IMPORTANCE OF NUTRIENT ENRICHMENT AND HERBIVORY ON MACROALGAL COMMUNITIES NEAR NORMAN'S POND CAY, EXUMAS CAYS, BAHAMAS: A "NATURAL" ENRICHMENT EXPERIMENT. (R830414)

    EPA Science Inventory

    The simultaneous effects of grazing and nutrient enrichment on macroalgal communities were experimentally investigated using plastic mesh enclosure/exclosure cages along a natural nutrient (DIN, SRP) gradient from the discharge of a tidal mangrove creek on the west side of Nor...

  2. What Paradox? Referential Cues Allow for Infant Use of Phonetic Detail in Word Learning

    ERIC Educational Resources Information Center

    Fennell, Christopher T.; Waxman, Sandra R.

    2010-01-01

    Past research has uncovered a surprising paradox: Although 14-month-olds have exquisite phonetic discrimination skills (e.g., distinguishing [b] from [d]), they have difficulty using phonetic detail when mapping "novel" words to objects in laboratory tasks (confusing "bin" and "din"). While some have attributed infants' difficulty to immature word…

  3. Evaluation of a direct injection nebulizer interface for flow injection analysis and high performance liquid chromatography with inductively coupled plasma-atomic emission spectroscopic detection

    SciTech Connect

    LaFreniere, K.E.

    1986-06-01

    A direct injection nebulizer (DIN) was designed, developed, and evaluated to determine its potential utilization as an effective interface for flow injection analysis (FIA) and high performance liquid chromatography (HPLC) coupled with inductively coupled plasma-atomic emission spectroscopic detection. The analytical figures of merit for the DIN when used as an interface for FIA-ICP-AES were found to be comparable to or better than those obtained with conventional pneumatic nebulization in terms of limits of detection (LODs), reproducibility, linearity, and interelement effects. Stable plasma operation was maintained for the DIN sample introduction of a variety of pure organic solvents, including acetonitrile, methanol, methylisobutylketone, and pyridine. The HPLC-DIN-ICP-AES facility was specifically applied for the speciation of inorganic and organometallic species contained in synthetic mixtures, vanilla extracts, and a variety of energy-related materials, such as shale oil process water, coal extracts, shale oil, crude oil, and an SRC II. Suggestions for future research are also considered. 227 refs., 44 figs., 15 tabs.

  4. Evaluation of a direct injection nebulizer interface for flow injection analysis and high performance liquid chromatography with inductively coupled plasma-atomic emission spectroscopic detection

    SciTech Connect

    LaFreniere, K.E.

    1986-01-01

    A direct injection nebulizer (DIN) was designed, developed and evaluated to determine its potential utilization as an effective interface for flow injection analysis (FIA) and high performance liquid chromatography (HPLC) coupled with inductively coupled plasma-atomic emission spectroscopic detection. The analytical figures of merit for the DIN when used as an interface for FIA-ICP-AES were found to be comparable to or better than those obtained with conventional pneumatic nebulization in terms of limits of detection (LODs), reproducibility, linearity, and interelement effects. In the HPLC mode, the LODDs were found to be comparable to those obtained by continuous-flow sample introduction into the ICP, or inferior by up to only a factor of four. Stable plasma operation was maintained for the DIN sample introduction of a variety of pure organic solvents, including acetonitrile, methanol, methyl-isobutylketone, and pyridine. The HPLC-DIN-ICP-AES facility was specifically applied for the speciation of inorganic and organo-metallic species contained in synthetic mixtures, vanilla extracts and a variety of energy-related materials, such as shale oil process water, coal extracts, shale oil, crude oil, and an SRC II. Suggestions for future research are also considered.

  5. In the Social Register: Pronoun Choice in Norwegian and English.

    ERIC Educational Resources Information Center

    Mills, Carl

    Choice of second-person pronouns can help explain the intersection of language, personality, and culture. Changes in modern Norway are described in which the polite forms "de,""dem"/"dykk," and "deres"/"dykkar" have been replaced in all except commercial, government, or ultra-polite speech by the familiar terms "du,""deg"/"dae," and "din." Some…

  6. Monitoring of Land Subsidence in Ravenna Municipality Using Integrated SAR - GPS Techniques: Description and First Results

    NASA Astrophysics Data System (ADS)

    Artese, G.; Fiaschi, S.; Di Martire, D.; Tessitore, S.; Fabris, M.; Achilli, V.; Ahmed, A.; Borgstrom, S.; Calcaterra, D.; Ramondini, M.; Artese, S.; Floris, M.; Menin, A.; Monego, M.; Siniscalchi, V.

    2016-06-01

    The Emilia Romagna Region (N-E Italy) and in particular the Adriatic Sea coastline of Ravenna, is affected by a noticeable subsidence that started in the 1950s, when the exploitation of on and off-shore methane reservoirs began, along with the pumping of groundwater for industrial uses. In such area the current subsidence rate, even if lower than in the past, reaches the -2 cm/y. Over the years, local Authorities have monitored this phenomenon with different techniques: spirit levelling, GPS surveys and, more recently, Differential Interferometric Synthetic Aperture Radar (DInSAR) techniques, confirming the critical situation of land subsidence risk. In this work, we present the comparison between the results obtained with DInSAR and GPS techniques applied to the study of the land subsidence in the Ravenna territory. With regard to the DInSAR, the Small Baseline Subset (SBAS) and the Coherent Pixel Technique (CPT) techniques have been used. Different SAR datasets have been exploited: ERS-1/2, ENVISAT, TerraSAR-X and Sentinel-1. Some GPS campaigns have been also carried out in a subsidence prone area. 3D vertices have been selected very close to existing persistent scatterers in order to link the GPS measurement results to the SAR ones. GPS data were processed into the International reference system and the comparisons between the coordinates, for the first 6 months of the monitoring, provided results with the same trend of the DInSAR data, even if inside the precision of the method.

  7. Diaphragm mechanics in dogs with unilateral emphysema.

    PubMed Central

    Hubmayr, R D; Farkas, G A; Tao, H Y; Sieck, G C; Margulies, S S

    1993-01-01

    We studied dogs with unilateral papain-induced emphysema to answer two questions: (1) Do emphysema lung-apposed hemidiaphragm (DiE) and normal lung-apposed hemidiaphragm (DiN) have equal capacities for lowering lung surface pressure? and (2) Are side-to-side differences in intrathoracic pressure the result of unequal force outputs by DiE and DiN or are they caused by differences in their mechanical efficiency as pressure generators? After the airways of the emphysematous and normal lungs were intubated with a dual lumen endotracheal tube, both phrenic nerves were maximally stimulated at rates between 1 and 50 Hz and the changes in airway occlusion pressure (delta PaoE,N) and diaphragm length (sonomicrometry) were recorded. In all animals, delta PaoN exceeded delta PaoE. Differences in pressure ranged from 1.2 +/- 0.6 cm H2O during a twitch to 6.0 +/- 2.9 cm H2O during a 50-Hz tetanus. Midcostal bundles of DiE shortened less than corresponding bundles of DiN, but both reached the same active length relative to their optimal lengths, which were measured in vitro. There was no significant difference in fiber type distribution, fiber cross-sectional area, or maximal isometric tetanic tensions among midcostal regions of DiE and DiN. We conclude that unilateral hyperinflation impairs the mechanical efficiency of the apposing hemidiaphragm as a pressure generator. PMID:8473503

  8. Factors influencing export of dissolved inorganic nitrogen by major rivers: A new seasonal, spatially explicit, global model - 2012

    EPA Science Inventory

    Background/Question/Methods Substantial effort has focused on understanding spatial variation in dissolved inorganic nitrogen (DIN) export to the coastal zone and specific basins have been studied in some depth. Much less is known, however, about seasonal patterns and zone and ...

  9. Managing & Re-Using Didactical Expertise: The Didactical Object Model

    ERIC Educational Resources Information Center

    Pawlowski, Jan M.; Bick, Markus

    2006-01-01

    The DIN Didactical Object Model extends the approaches of existing Educational Modeling Languages introducing specifications for contexts and experiences. In this paper, we show how the Didactical Object Model can be used for sharing didactical expertise. Educational Modeling Languages change the design paradigm from content orientation towards…

  10. The low-affinity ATP binding site of the Escherichia coli SecA dimer is localized at the subunit interface.

    PubMed

    van der Wolk, J P; Boorsma, A; Knoche, M; Schäfer, H J; Driessen, A J

    1997-12-01

    The homodimeric SecA protein is the ATP-dependent force generator in the Escherichia coli precursor protein translocation cascade. SecA contains two essential nucleotide binding sites (NBSs), i.e., NBS1 and NBS2 that bind ATP with high and low affinity, respectively. The photoactivatable bifunctional cross-linking agent 3'-arylazido-8-azidoadenosine 5'-triphosphate (diN3ATP) was used to investigate the spatial arrangement of the nucleotide binding sites of SecA. DiN3ATP is an authentic ATP analogue as it supports SecA-dependent precursor protein translocation and translocation ATPase. UV-induced photo-cross-linking of the diN3ATP-bound SecA results in the formation of stable dimeric species of SecA. D209N SecA, a mutant unable to bind nucleotides at NBS1, was also photo-cross-linked by diN3ATP, whereas no cross-linking occurred with the NBS2 mutant R509K SecA. We concluded that the low-affinity NBS2, which is located in the carboxyl-terminal half of SecA, is the site of crosslinking and that NBS2 binds nucleotides at or near the subunit interface of the SecA dimer. PMID:9398216

  11. Education in Spotlight on Statewide Ballots

    ERIC Educational Resources Information Center

    Ash, Katie

    2008-01-01

    Education issues are poised to break through the din of presidential politics and economic anxiety in more than a dozen states next month, as voters confront ballot questions and constitutional amendments involving K-12 policy and school finance. High on the list are gambling referendums in six states--Arkansas, Colorado, Maine, Maryland,…

  12. A Connector between Active Laboratory Probes and Computer Interfaces of Different Brands

    ERIC Educational Resources Information Center

    Hui, Kaleonui J.; Coney, John P.; Binder, P.-M.

    2016-01-01

    In PASCO's Technical Article #763, it is stated that "PASCO [also] makes sensors with an 8-pin DIN connector. These sensors cannot be used with the Vernier interfaces, as they have different power requirements." Recently we had the need to make such connections in a 10-station freshman lab. Since the Vernier input is a 6-way BT 631A plug…

  13. Assessing the potential to decrease the Gulf of Mexico hypoxic zone with Midwest US perennial cellulosic feedstock production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The goal of this research is to determine the changes in streamflow, dissolved inorganic nitrogen (DIN) leaching and export to the Gulf of Mexico associated with a range of large-scale dedicated perennial cellulosic bioenergy production scenarios within in the Mississippi-Atchafalaya River Basin (MA...

  14. Cultural and Technical Evaluation of Heating Alternatives to Improve Indoor Air Quality on the Navajo Nation

    EPA Science Inventory

    In the Navajo Nation it is estimated that 62% of households use wood as their primary means of heating1. A 2010 study by the U.S. Geological Survey (USGS) and Diné College found that in Shiprock, NM, the largest town in the Navajo Nation (pop. = 8,300)2, heating is often w...

  15. PHOSPHORUS-RICH WATERS AT GLOVERS REEF, BELIZE? (R830414)

    EPA Science Inventory

    Table 1. Concentrations (small mu, GreekM) of ammonium, nitrate, dissolved inorganic nitrogen (DIN=ammonium + nitrate + nitrite), PO43−–P (...

  16. 75 FR 65035 - Notice of Permit Applications Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-21

    ... be used to: (a) Trace the movement of persistent organic pollutants (POPs) stored in glacier ice into... between global climate change and mobilization of glacier reservoirs of contaminants, and is likely to serve as a case study for understanding the potential future impact of contaminants store din...

  17. WATER QUALITY MODELING IN THE RIO CHONE ESTUARY

    EPA Science Inventory

    Water quality in the Rio Chone Estuary, a seasonally inverse, tropical estuary, in Ecuador was characterized by modeling the distribution of biochemical oxygen demand (BOD) and dissolved inorganic nitrogen (DIN) within the water column. These two variables are modeled using modif...

  18. The Flogging of For-Profit Colleges

    ERIC Educational Resources Information Center

    Hassler, Richard P.

    2006-01-01

    A din of opprobrium rises from the academy against for-profit education. But a name like "The University of Phoenix" is not misleading to students, Richard P. Hassler argues, even though the dividends that that large public corporation pays its shareholders derive narrowly from career preparation, rather than from more rarefied cultivations of the…

  19. Constraining nitrogen inputs to urban streams from leaking sewer infrastructure using inverse modeling: Implications for urban water quality

    NASA Astrophysics Data System (ADS)

    Sikora, M. T.; Elliott, E. M.; Bain, D. J.

    2011-12-01

    Excess fixed nitrogen contributes to stream degradation in densely populated regions, compounding problems of surface water contamination in urban landscapes. In particular, leaking sewer infrastructure is an acknowledged source of non-point source (NPS) nitrogen pollution to ground- and surface water in urban areas; however quantification of such contributions is exceedingly limited. This lack of knowledge inhibits efforts to understand urban nitrogen retention and export, despite the potential for this source to impact downstream water quality. Nine Mile Run (NMR), a restored urban stream in Pittsburgh, Pennsylvania (USA), drains a 1600 hectare urban watershed characterized by a high degree of impervious surface cover (38%). For years known locally as "stink creek," NMR remains significantly impacted by combined sewer overflows, leaky sewers, and degraded water quality. In order to assess sources of impairment, water samples were collected from four locations bi-weekly over two years, intensive sampling was conducted during one summer storm and DIN concentrations in water samples were analyzed (where DIN = nitrate + nitrite + ammonium). Using DIN concentrations, discharge records, published estimates of urban watershed nitrogen retention, and known inputs of atmospherically deposited nitrogen, a watershed nitrogen budget was constructed for NMR and subsequently inverted to constrain potential sewage inputs. Retention estimates ranging from 65 to 85% were applied and resulting calculations indicate that DIN contributions from sewage ranged from 5.5 to 25 kg ha-1yr-1. This research documents the potential contribution of sewage to DIN loads in urban streams and highlights the challenges of reducing nutrient pollution to receiving waters in cities with aging, degraded sewer lines.

  20. Reviews and syntheses: measuring ecosystem nitrogen status - a comparison of proxies

    NASA Astrophysics Data System (ADS)

    Almaraz, Maya; Porder, Stephen

    2016-09-01

    There are many proxies used to measure nitrogen (N) availability in watersheds, but the degree to which they do (or do not) correlate within a watershed has not been systematically addressed. We surveyed the literature for intact forest or grassland watersheds globally, in which several metrics of nitrogen availability have been measured. Our metrics included the following: foliar δ15N, soil δ15N, net nitrification, net N mineralization, and the ratio of dissolved inorganic to organic nitrogen (DIN : DON) in soil solution and streams. We were particularly interested in whether terrestrial and stream based proxies for N availability were correlated where they were measured in the same place. Not surprisingly, the strongest correlation (Kendall's τ) was between net nitrification and N mineralization (τ = 0.71, p < 0.0001). Net nitrification and N mineralization were each correlated with foliar and soil δ15N (p < 0.05). Foliar and soil δ15N were more tightly correlated in tropical sites (τ = 0.68, p < 0.0001), than in temperate sites (τ = 0.23, p = 0.02). The only significant correlations between terrestrial- and water-based metrics were those of net nitrification (τ = 0.48, p = 0.01) and N mineralization (τ = 0.69, p = 0.0001) with stream DIN : DON. The relationship between stream DIN : DON with both net nitrification and N mineralization was significant only in temperate, but not tropical regions. To our surprise, we did not find a significant correlation between soil δ15N and stream DIN : DON, despite the fact that both have been used to infer spatially or temporally integrated N status. Given that both soil δ15N and stream DIN : DON are used to infer long-term N status, their lack of correlation in watersheds merits further investigation.

  1. In situ measurements of microbially-catalyzed nitrification and nitrate reduction rates in an ephemeral drainage channel receiving water from coalbed natural gas discharge, Powder River Basin, Wyoming, USA

    USGS Publications Warehouse

    Harris, S.H.; Smith, R.L.

    2009-01-01

    Nitrification and nitrate reduction were examined in an ephemeral drainage channel receiving discharge from coalbed natural gas (CBNG) production wells in the Powder River Basin, Wyoming. CBNG co-produced water typically contains dissolved inorganic nitrogen (DIN), primarily as ammonium. In this study, a substantial portion of discharged ammonium was oxidized within 50??m of downstream transport, but speciation was markedly influenced by diel fluctuations in dissolved oxygen (> 300????M). After 300??m of transport, 60% of the initial DIN load had been removed. The effect of benthic nitrogen-cycling processes on stream water chemistry was assessed at 2 locations within the stream channel using acrylic chambers to conduct short-term (2-6??h), in-stream incubations. The highest ambient DIN removal rates (2103????mol N m- 2 h- 1) were found at a location where ammonium concentrations > 350????M. This occurred during light incubations when oxygen concentrations were highest. Nitrification was occurring at the site, however, net accumulation of nitrate and nitrite accounted for < 12% of the ammonium consumed, indicating that other ammonium-consuming processes were also occurring. In dark incubations, nitrite and nitrate consumption were dominant processes, while ammonium was produced rather than consumed. At a downstream location nitrification was not a factor and changes in DIN removal rates were controlled by nitrate reduction, diel fluctuations in oxygen concentration, and availability of electron donor. This study indicates that short-term adaptation of stream channel processes can be effective for removing CBNG DIN loads given sufficient travel distances, but the long-term potential for nitrogen remobilization and nitrogen saturation remain to be determined.

  2. Historical trend of nitrogen and phosphorus loads from the upper Yangtze River basin and their responses to the Three Gorges Dam.

    PubMed

    Sun, Chengchun; Shen, Zhenyao; Liu, Ruimin; Xiong, Ming; Ma, Fangbing; Zhang, Ouyang; Li, Yangyang; Chen, Lei

    2013-12-01

    Excessive inputs of nitrogen and phosphorus (N and P) degrade surface water quality worldwide. Impoundment of reservoirs alters the N and P balance of a basin. In this study, riverine nutrient loads from the upper Yangtze River basin (YRB) at the Yichang station were estimated using Load Estimator (LOADEST). Long-term load trends and monthly variabilities during three sub-periods based on the construction phases of the Three Gorges Dam (TGD) were analyzed statistically. The dissolved inorganic nitrogen (DIN) loads from the upper YRB for the period from 1990 to 2009 ranged from 30.47 × 10(4) to 78.14 × 10(4) t, while the total phosphorus (TP) loads ranged from 2.54 × 10(4) to 7.85 × 10(4) t. DIN increased rapidly from 1995 to 2002 mainly as a result of increased fertilizer use. Statistics of fertilizer use in the upper YRB agreed on this point. However, the trend of the TP loads reflected the combined effect of removal by sedimentation in reservoirs and increased anthropogenic inputs. After the TGD impoundment in 2003, decreasing trends in both DIN and TP loads were found. The reduction in DIN was mainly caused by ammonium consumption and transference. From an analysis of monthly loads, it was found that DIN had a high correlation to discharges. For TP loads, an average decrease of 4.91 % in October was found when the TGD impoundment occurred, but an increase of 4.23 % also occurred in July, corresponding to the washout from sediment deposited in the reservoir before July. Results of this study revealed the TGD had affected nutrient loads in the basin, and it had played a role in nutrient reduction after its operation.

  3. Seasonal Patterns of Nitrogen and Phosphorus Limitation in Four German Lakes and the Predictability of Limitation Status from Ambient Nutrient Concentrations

    PubMed Central

    Kolzau, Sebastian; Wiedner, Claudia; Rücker, Jacqueline; Köhler, Jan; Köhler, Antje; Dolman, Andrew M.

    2014-01-01

    To identify the seasonal pattern of nitrogen (N) and phosphorus (P) limitation of phytoplankton in four different lakes, biweekly experiments were conducted from the end of March to September 2011. Lake water samples were enriched with N, P or both nutrients and incubated under two different light intensities. Chlorophyll a fluorescence (Chla) was measured and a model selection procedure was used to assign bioassay outcomes to different limitation categories. N and P were both limiting at some point. For the shallow lakes there was a trend from P limitation in spring to N or light limitation later in the year, while the deep lake remained predominantly P limited. To determine the ability of in-lake N:P ratios to predict the relative strength of N vs. P limitation, three separate regression models were fit with the log-transformed ratio of Chla of the P and N treatments (Response ratio = RR) as the response variable and those of ambient total phosphorus:total nitrogen (TN:TP), dissolved inorganic nitrogen:soluble reactive phosphorus (DIN:SRP), TN:SRP and DIN:TP mass ratios as predictors. All four N:P ratios had significant positive relationships with RR, such that high N:P ratios were associated with P limitation and low N:P ratios with N limitation. The TN:TP and DIN:TP ratios performed better than the DIN:SRP and TN:SRP in terms of misclassification rate and the DIN:TP ratio had the highest R2 value. Nitrogen limitation was predictable, frequent and persistent, suggesting that nitrogen reduction could play a role in water quality management. However, there is still uncertainty about the efficacy of N restriction to control populations of N2 fixing cyanobacteria. PMID:24755935

  4. Mexico City land subsidence in 2014-2015 with Sentinel-1 IW TOPS: Results using the Intermittent SBAS (ISBAS) technique

    NASA Astrophysics Data System (ADS)

    Sowter, Andrew; Bin Che Amat, Moh.; Cigna, Francesca; Marsh, Stuart; Athab, Ahmed; Alshammari, Lubna

    2016-10-01

    Differential Interferometric Synthetic Aperture Radar (DInSAR) can be considered as an efficient and cost effective technique for monitoring land subsidence due to its large spatial coverage and high accuracy provided. The recent commissioning of the first Sentinel-1 satellite offers improved support to operational surveys using DInSAR due to regular observations from a wide-area product. In this paper we show the results of an intermittent small-baseline subset (ISBAS) time-series analysis of 18 Interferometric Wide swath (IW) products of a 39,000 km2 area of Mexico acquired between 3 October 2014 and 7 May 2015 using the Terrain Observation with Progressive Scans in azimuth (TOPS) imaging mode. The ISBAS processing was based upon the analysis of 143 small-baseline differential interferograms. After the debursting, merging and deramping steps necessary to process Sentinel-1 IW products, the method followed a standard approach to the DInSAR analysis. The Sentinel-1 ISBAS results confirm the magnitude and extent of the deformation that was observed in Mexico City, Chalco, Ciudad Nezahualcóyotl and Iztapalapa by other C-band and L-band DInSAR studies during the 1990s and 2000s. Subsidence velocities from the Sentinel-1 analysis are, in places, in excess of -24 cm/year along the satellite line-of-sight, equivalent to over ∼40 cm/year vertical rates. This paper demonstrates the potential of Sentinel-1 IW TOPS imagery to support wide-area DInSAR surveys over what is a very large and diverse area in terms of land cover and topography.

  5. Estimating the terrestrial N processes in subtropical mountainous forestry catchment through INCA-N: A case study in FuShan catchment, Taiwan

    NASA Astrophysics Data System (ADS)

    Lu, Meng-Chang; Huang, -Chuan, Jr.; Chang, Chung-Te; Shih, Yu-Ting; Lin, Teng-Chiu

    2016-04-01

    The riverine DIN is a crucial indicator for eutrophication in river network. The riverine DIN export in Taiwan is featured by the extremely high yield, ~3800 kg-N km-2yr-1, nearly 20-fold than the global average, showing the interesting terrestrial N process yet rarely documented. In this study we collected the DIN samples in rainwater, soil water, and stream water in a mountainous forest watershed, FuShan experimental forest watershed 1 (WS1) which is a natural broadleaf forest without human activities. Based on the intensive observations, we applied the INCA-N to simulate the riverine DIN response and thus estimate the terrestrial N processes in a global synthesis. The result showed that both discharge and DIN yield were simulated well with the average Nash-Sutcliffe efficiency coefficient of 0.83 and 0.76 , respectively. Among all N processes, N uptake, mineralization, nitrification, denitrfication, and immobilization are significantly positive correlated with soil moisture (R2>0.99), which indicates that soil moisture greatly influences N cycle processes. The average rate of mineralization and nitrification in wet years are consistent with documented values, whereas the rates in dry years are lower than the observations. Despite the high nitrification rate, the secondary forest may uptake abundant N indicating the plant uptake, which responds for removing considerable nitrate, is a controlling factor in forest ecosystem. Our simulated denitrification rate falls between the documented rates of temperate forest and agricultural area, and that may be affected by the high N-deposition in Taiwan. Simulated in-stream denitrification rate is less than 10% of the rate in soil, and is a little lower than that in temperate forest. This preliminary simulation provides an insightful guide to establish the monitoring programme and improve the understanding of N cycle in subtropical.

  6. Historical trend of nitrogen and phosphorus loads from the upper Yangtze River basin and their responses to the Three Gorges Dam.

    PubMed

    Sun, Chengchun; Shen, Zhenyao; Liu, Ruimin; Xiong, Ming; Ma, Fangbing; Zhang, Ouyang; Li, Yangyang; Chen, Lei

    2013-12-01

    Excessive inputs of nitrogen and phosphorus (N and P) degrade surface water quality worldwide. Impoundment of reservoirs alters the N and P balance of a basin. In this study, riverine nutrient loads from the upper Yangtze River basin (YRB) at the Yichang station were estimated using Load Estimator (LOADEST). Long-term load trends and monthly variabilities during three sub-periods based on the construction phases of the Three Gorges Dam (TGD) were analyzed statistically. The dissolved inorganic nitrogen (DIN) loads from the upper YRB for the period from 1990 to 2009 ranged from 30.47 × 10(4) to 78.14 × 10(4) t, while the total phosphorus (TP) loads ranged from 2.54 × 10(4) to 7.85 × 10(4) t. DIN increased rapidly from 1995 to 2002 mainly as a result of increased fertilizer use. Statistics of fertilizer use in the upper YRB agreed on this point. However, the trend of the TP loads reflected the combined effect of removal by sedimentation in reservoirs and increased anthropogenic inputs. After the TGD impoundment in 2003, decreasing trends in both DIN and TP loads were found. The reduction in DIN was mainly caused by ammonium consumption and transference. From an analysis of monthly loads, it was found that DIN had a high correlation to discharges. For TP loads, an average decrease of 4.91 % in October was found when the TGD impoundment occurred, but an increase of 4.23 % also occurred in July, corresponding to the washout from sediment deposited in the reservoir before July. Results of this study revealed the TGD had affected nutrient loads in the basin, and it had played a role in nutrient reduction after its operation. PMID:23749367

  7. FOREWORD: VI Workshop in Electron Volt Neutron Spectroscopy: Frontiers and Horizons

    NASA Astrophysics Data System (ADS)

    Seel, A. G.; Senesi, R.; Fernandez-Alonso, F.

    2014-12-01

    January 2014 saw the congregation in Abingdon (UK) of scientists from across the world, to discuss the current state and future of spectroscopy using epithermal neutrons. This meeting was the sixth in a series of workshops held in collaboration between the Science and Technology Facilities Council (UK) and the Consiglio Nazionale delle Ricerche (Italy), aimed at bringing together researchers with an interest in the use of electron-volt neutrons in spectroscopic studies [1]. This technique is termed Deep Inelastic Neutron Scattering (DINS), and also Neutron Compton Scattering (NCS) in reference to the analogy with Compton scattering of X-rays from electrons. In particular, this meeting centred jointly around experimentalists and theoreticians, formulating animated discussions as to the current overview of DINS and future horizons facing the field. The use of electron Volt neutrons for spectroscopic measurements dates back to the advent of proton-driven spallation neutron sources in the 1970s and 1980s. Following an initial scientific meeting in Los Alamos (USA) [2], the first two meetings in this series were held in Abingdon (UK) in 1995 and 1998, with subsequent meetings held in Santa Fe (USA) in 2005 [3], Oak Ridge National Laboratory (USA) in 2006 [4], and Rome, Italy; in 2010 [5]. The flagship instrument serving a continual user-programme for DINS measurements, and the main focus of this meeting, has been the VESUVIO spectrometer at ISIS [6, 7]. Subsequent instruments like SEQUOIA in the USA [8, 9] and a newer spectrometer in the Bariloche LINAC in Argentina [10, 11] have also been commissioned and began serving a growing user community. The availability of DINS measurements has extended the range of possible spectroscopic techniques that utilise neutrons into the kinematic region of high energy and momentum transfers, shown schematically in Figure 1. Spectroscopic instrument suites such as that of ISIS are thus able to probe processes on timescales across nine

  8. Export of dissolved inorganic nutrients to the northern Indian Ocean from the Indian monsoonal rivers during discharge period

    NASA Astrophysics Data System (ADS)

    Krishna, M. S.; Prasad, M. H. K.; Rao, D. B.; Viswanadham, R.; Sarma, V. V. S. S.; Reddy, N. P. C.

    2016-01-01

    Coastal regions are highly productive due to the nutrients largely supplied by rivers. To examine the contribution of dissolved inorganic nutrients (DIN) by Indian rivers to coastal waters, data were collected near the freshwater heads of 27 monsoonal rivers of peninsular India during three weeks in late July to mid-August, the middle of the principal runoff period of the southwest monsoon of 2011. Twelve researchers in four groups, equipped with car and portable laboratory equipment, sampled mid-stream of each estuary using mechanized boat, and filtered and partly analyzed the water in the evening. The estimated exports were 0.22 ± 0.05, 0.11 ± 0.03, and 1.03 ± 0.26 Tg yr-1 for dissolved inorganic nitrogen, phosphorus and silicate, respectively. Higher amounts of DIN reach the Bay of Bengal than the Arabian Sea due to the higher volume (∼76%) of discharge to the former. In contrast, the export of dissolved inorganic nitrogen is almost same to the Bay of Bengal (0.12 ± 0.03 Tg yr-1) and Arabian Sea (0.10 ± 0.02 Tg yr-1) principally due to the polluted Narmada and Tapti rivers in the northwest. Including input from the glacial rivers, Ganges, Brahmaputra and Indus, it is estimated that the northern Indian Ocean receives ∼1.84 ± 0.46, 0.28 ± 0.07 and 3.58 ± 0.89 Tg yr-1 of nitrate, phosphate and silicate, respectively, which are significantly lower than the earlier estimates of DIN export from the Indian rivers based on DIN measured in the mid or upstream rivers. Such low fluxes in this study were attributed to efficient retention/elimination of DIN (∼91%) before reaching the coastal ocean. Hence, this study suggests that the importance of sampling locations for estimating nutrient fluxes to the coastal ocean. Riverine DIN export of 1.84 ± 0.46 Tg yr-1 would support 12.2 ± 3.1 Tg C yr-1 of new production in coastal waters of the northern Indian Ocean that results in a removal of 12.2 ± 3.1 Tg atmospheric CO2 yr-1.

  9. Mapping Slumgullion Landslide in Colorado, USA Using Airborne Repeat-Pass InSAR

    NASA Astrophysics Data System (ADS)

    Lee, H.; Shrestha, R. L.; Carter, W. E.; Glennie, C. L.; Wang, G.; Lu, Z.; Fernandez-Diaz, J. C.; Cao, N.; Zaugg, E.

    2015-12-01

    Interferometric Synthetic Aperture Radar (InSAR) uses two or more SAR images over the same area to determine landscape topography or ground deformation. An interferogram, generated by the phase components of two coherent SAR images, depicts range changes between the radar and the ground resolution elements, and can be used to derive both landscape topography and subtle changes in surface elevation. However, spaceborne repeat-pass interferometry has two main drawbacks: effects due to differences in atmospheric temperature, pressure, and water vapour at two observation times, and loss of coherence due to long spatial and temporal baselines between observations. Airborne repeat-pass interferometry does not suffer from these drawbacks. The atmospheric effect in case of airborne DInSAR becomes negligible due to smaller swath coverage, and the coherence can be maintained by using smaller spatial and temporal baselines. However, the main technical limitation concerning airborne DInSAR is the need of precise motion compensation with an accurate navigation system to correct for the significant phase errors due to typical flight instability from air turbulence. Here, we present results from a pilot study conducted on July 2015 using both X-band and L-band SlimSAR airborne system over the Slumgullion landslide in Colorado in order to (1) acquire the differential interferograms from the airborne platform, (2) understand their source of errors, and (3) pave a way to improve the precision of the derived surface deformation. The landslide movement estimated from airborne DInSAR is also compared with coincident GPS, terrestrial laser scanning (TLS), airborne LiDAR, and spaceborne DInSAR measurements using COSMO-SkyMed images. The airborne DInSAR system has a potential to provide time-transient variability in land surface topography with high-precision and high-resolution, and provide researchers with greater flexibility in selecting the temporal and spatial baselines of the data

  10. Two-dimensional Co-Seismic Surface Displacements Field of the Chi-Chi Earthquake Inferred from SAR Image Matching

    PubMed Central

    Hu, Jun; Li, Zhi-Wei; Ding, Xiao-Li; Zhu, Jian-Jun

    2008-01-01

    The Mw=7.6 Chi-Chi earthquake in Taiwan occurred in 1999 over the Chelungpu fault and caused a great surface rupture and severe damage. Differential Synthetic Aperture Radar Interferometry (DInSAR) has been applied previously to study the co-seismic ground displacements. There have however been significant limitations in the studies. First, only one-dimensional displacements along the Line-of-Sight (LOS) direction have been measured. The large horizontal displacements along the Chelungpu fault are largely missing from the measurements as the fault is nearly perpendicular to the LOS direction. Second, due to severe signal decorrelation on the hangling wall of the fault, the displacements in that area are un-measurable by differential InSAR method. We estimate the co-seismic displacements in both the azimuth and range directions with the method of SAR amplitude image matching. GPS observations at the 10 GPS stations are used to correct for the orbital ramp in the amplitude matching and to create the two-dimensional (2D) co-seismic surface displacements field using the descending ERS-2 SAR image pair. The results show that the co-seismic displacements range from about -2.0 m to 0.7 m in the azimuth direction (with the positive direction pointing to the flight direction), with the footwall side of the fault moving mainly southwards and the hanging wall side northwards. The displacements in the LOS direction range from about -0.5 m to 1.0 m, with the largest displacement occuring in the northeastern part of the hanging wall (the positive direction points to the satellite from ground). Comparing the results from amplitude matching with those from DInSAR, we can see that while only a very small fraction of the LOS displacement has been recovered by the DInSAR mehtod, the azimuth displacements cannot be well detected with the DInSAR measurements as they are almost perpendicular to the LOS. Therefore, the amplitude matching method is obviously more advantageous than the DIn

  11. [Implementation of a quality management system for research and teaching in a university department of epidemiology].

    PubMed

    Berghöfer, Anne; de Bucourt, Maximilian; Willich, Stefan N

    2007-01-01

    The present article analyses the development and implementation of quality management systems at institutes for clinical and theoretical research as exemplified by the Charité University Medical Centre's Institute for Social Medicine, Epidemiology, and Health Economics in Berlin. The Institute established its quality management system independently (i.e. without external consultants) and was able to fulfil the standard requirements within one year. The quality management system was successfully certified under European Standard DIN EN ISO 9001:2000 by an authorized external DIN-accredited inspection authority in October 2005 and recertified one year later. The certification covered the areas of research, teaching, and supporting administration. Our description of the individual steps involved and the corresponding timeline may be useful to organizations of a similar type and size seeking professional external certification.

  12. Geographic Variation in the Relationship between Human Lyme Disease Incidence and Density of Infected Host-Seeking Ixodes scapularis Nymphs in the Eastern United States

    PubMed Central

    Pepin, Kim M.; Eisen, Rebecca J.; Mead, Paul S.; Piesman, Joseph; Fish, Durland; Hoen, Anne G.; Barbour, Alan G.; Hamer, Sarah; Diuk-Wasser, Maria A.

    2012-01-01

    Prevention and control of Lyme disease is difficult because of the complex biology of the pathogen's (Borrelia burgdorferi) vector (Ixodes scapularis) and multiple reservoir hosts with varying degrees of competence. Cost-effective implementation of tick- and host-targeted control methods requires an understanding of the relationship between pathogen prevalence in nymphs, nymph abundance, and incidence of human cases of Lyme disease. We quantified the relationship between estimated acarological risk and human incidence using county-level human case data and nymphal prevalence data from field-derived estimates in 36 eastern states. The estimated density of infected nymphs (mDIN) was significantly correlated with human incidence (r = 0.69). The relationship was strongest in high-prevalence areas, but it varied by region and state, partly because of the distribution of B. burgdorferi genotypes. More information is needed in several high-prevalence states before DIN can be used for cost-effectiveness analyses. PMID:22665620

  13. The monitoring of glacial migration in Greenland by multi sensor data fusion

    NASA Astrophysics Data System (ADS)

    Park, H.; Kim, J.; yun, H.; Choi, Y.

    2013-12-01

    The retreatment of ice sheet in Greenland by global warming is now firmly confirmed by variety of observations. However, the arguments about the melting speed of ice sheet is still undergoing owing to the absence of the quantitative measurement method to continuously trace the direction and the speed of icecap change. Thus, we tested a scheme to spatially and temporally monitor the migration of ice sheet with high accuracy employing multi sensor information and their data fusion. The target areas were established in Jakoshavm and Mittivakkat glaciers where the shrinking of glaciers has been obvious for the last one century. At first, in both well-known Greenland glaciers, Differential Interferometric SAR (DInSAR) campaigns which are highly useful to monitor the glacial retreat have been undertaking employing 30 European remote sensing satellite (ERS) and 15 Advanced Land Observing Satellite (ALOS) Phased Array type L-band Synthetic Aperture Radar (PALSAR) InSAR pairs. Since base DEM quality for DInSAR analysis is poor and InSAR pixels are frequently de-correlated over ice body, two pass DInSAR doesn't produce reliable outputs. Thus the time series analyses of Permanent Scatterer and Small Baseline Subset are expected to effectively trace the translation of the glaciers and employed as the main methodology of DInSAR. Although DInSAR time series analysis effectively reconstructed temporal change of glaciers, the extracted glacial movements are projected values into line of sight direction of the sensor. Therefore it might be better to interpret them together with the other remote sensed data set for the fulfilment of useful directional measurements. In terms of such data fusion aspect, we also employ Co-registration of Optically Sensed Images and Correlation (CoSi-CORR, Leprince et al., 2007) technique, which is known as a tool for 2D change tracing, with ALOS Panchromatic Remote-sensing Instrument for Stereo Mapping (PRISM) to compensate for any line

  14. Abiotic factors influencing biomass accumulation of green tide causing Ulva spp. on Pyropia culture rafts in the Yellow Sea, China.

    PubMed

    Keesing, John K; Liu, Dongyan; Shi, Yajun; Wang, Yujue

    2016-04-15

    Annually recurrent green-tides in the Yellow Sea have been shown to result from direct disposal into the sea of fouling Ulva from Pyropia aquaculture. The role abiotic factors play in Ulva biomass accumulation on rafts was studied to find ways to mitigate this problem. Dissolved inorganic nitrogen (DIN) was very high at all sites, but the highest Ulva biomass was associated with the lowest DIN and anthropogenic N. Under luxuriant background nutrient conditions, variability in temperature and periods of emersion, rather than pH, light and salinity determined Ulva biomass. Two dominant species of Ulva displayed differing tolerances to temperature and desiccation which helped explain why Ulva prolifera dominates floating green-tides. Rather than trying to mitigate green-tides only by reducing nutrient pollution, an earlier harvest of Pyropia in southern Jiangsu Province especially before temperatures increase greatly above 10°C during April, could reduce the biomass of U. prolifera disposed from rafts.

  15. Department of Defense picture archiving and communication system acceptance testing: results and identification of problem components.

    PubMed

    Allison, Scott A; Sweet, Clifford F; Beall, Douglas P; Lewis, Thomas E; Monroe, Thomas

    2005-09-01

    The PACS implementation process is complicated requiring a tremendous amount of time, resources, and planning. The Department of Defense (DOD) has significant experience in developing and refining PACS acceptance testing (AT) protocols that assure contract compliance, clinical safety, and functionality. The DOD's AT experience under the initial Medical Diagnostic Imaging Support System contract led to the current Digital Imaging Network-Picture Archiving and Communications Systems (DIN-PACS) contract AT protocol. To identify the most common system and component deficiencies under the current DIN-PACS AT protocol, 14 tri-service sites were evaluated during 1998-2000. Sixteen system deficiency citations with 154 separate types of limitations were noted with problems involving the workstation, interfaces, and the Radiology Information System comprising more than 50% of the citations. Larger PACS deployments were associated with a higher number of deficiencies. The most commonly cited systems deficiencies were among the most expensive components of the PACS. PMID:15924273

  16. Precipitation of Laves phase in a 28%Cr-4%Ni-2%Mo-Nb superferritic stainless steel

    SciTech Connect

    Fontoura de Andrade, Thiago; Madeira Kliauga, Andrea; Plaut, Ronald Lesley; Padilha, Angelo Fernando

    2008-05-15

    The main objective of the present work was to study the precipitation of the Laves phase in the X1 CrNiMoNb 28 4 2 (Werkstoff-Nr. DIN 1.4575) superferritic stainless steel employing several complementary techniques of microstructural analysis. The phase that precipitated in largest quantity in the DIN 1.4575 steel was the sigma ({sigma}) phase. However, along grain boundaries, after aging at 850 deg. C, a Laves phase of the MgZn{sub 2} type, with a hexagonal C14 crystal structure and chemical composition (Fe,Cr,Ni){sub 2}(Nb,Mo,Si), was also identified. Growth of the Laves phase is curtailed by exhaustion of niobium of the matrix and by the presence of the sigma phase, which also precipitates in the vicinity of the grain boundaries, however in larger amounts. No chi ({chi}) or austenite phases were detected in the temperature range studied.

  17. Impacts of changing atmospheric deposition chemistry on nitrogen and phosphorus loading to Ganga River (India).

    PubMed

    Pandey, Jitendra; Singh, Anand V; Singh, Ashima; Singh, Rachna

    2013-08-01

    Investigations on atmospheric deposition (AD) and water chemistry along a 35 km stretch of Ganga River indicated that although N:P stoichiometry of AD did not change, there were over 1.4-2.0 fold increase in AD-NO₃⁻, AD-NH₄⁺ and AD-PO₄³⁻ overtime. Concentration of dissolved inorganic-N (DIN) in river showed significant positive correlations with AD-NO₃⁻ and runoff DIN. Similarly, dissolved reactive-P (DRP) in river showed significant positive correlation with AD-PO₄³⁻ and runoff DRP. The study shows that AD has become an important source of N and P input to Ganga River.

  18. Estructura orbital en el Problema Restringido Rectilíneo Isósceles

    NASA Astrophysics Data System (ADS)

    Orellana, R. B.

    Para definir problemas en Mecánica Celeste se utilizan diferentes parámetros. El conocimiento de la dinámica del problema para valores particulares de estos parámetros nos permite entender el comportamiento en casos más generales. El Problema Restringido Rectilíneo Isósceles puede ser considerado como el caso límite del Problema de Sitnikov cuando la excentricidad tiende a uno o como el Problema Isósceles cuando la masa central tiende a cero. Se ha compactificado el espacio de fases y analizado la dinámica en el límite. Esto ha permitido separar el espacio de fases en diferentes regiones dependiendo de las clases de órbitas.

  19. Improvement of an invA-based PCR for the specific detection of Salmonella typhimurium in organs of pigs.

    PubMed

    Scholz, H C; Arnold, T; Marg, H; Rösler, U; Hensel, A

    2001-01-01

    The aim of this study was to investigate the suitability of the invA-based polymerase chain reaction (PCR) assay for the specific detection of Salmonella in organs of experimentally infected pigs and to compare these results to classical bacterial culture. While the PCR conditions specified in the "Deutsche Industrie Norm", DIN 10135 (section 35 LMBG, 1999), cutle based on the publication of Rahn et al. 1992, revealed various unspecific amplification products, modifications of the PCR conditions allowed the specific amplification of the invA fragment from inner organs. The modified PCR assay correlates exactly with cultivation results (as required by DIN Norm 6579) and enables the detection of Salmonella within 48 hours with equal sensitivity compared to routine cultivation.

  20. Geographic variation in the relationship between human Lyme disease incidence and density of infected host-seeking Ixodes scapularis nymphs in the Eastern United States.

    PubMed

    Pepin, Kim M; Eisen, Rebecca J; Mead, Paul S; Piesman, Joseph; Fish, Durland; Hoen, Anne G; Barbour, Alan G; Hamer, Sarah; Diuk-Wasser, Maria A

    2012-06-01

    Prevention and control of Lyme disease is difficult because of the complex biology of the pathogen's (Borrelia burgdorferi) vector (Ixodes scapularis) and multiple reservoir hosts with varying degrees of competence. Cost-effective implementation of tick- and host-targeted control methods requires an understanding of the relationship between pathogen prevalence in nymphs, nymph abundance, and incidence of human cases of Lyme disease. We quantified the relationship between estimated acarological risk and human incidence using county-level human case data and nymphal prevalence data from field-derived estimates in 36 eastern states. The estimated density of infected nymphs (mDIN) was significantly correlated with human incidence (r = 0.69). The relationship was strongest in high-prevalence areas, but it varied by region and state, partly because of the distribution of B. burgdorferi genotypes. More information is needed in several high-prevalence states before DIN can be used for cost-effectiveness analyses.

  1. Do-It-Now building maintenance reengineering project

    SciTech Connect

    Apoddaca, L.; Ayotte, A.; Coffman, J.; Dukes, L.; Jojola, S.; Kadlec, J.; Letourneau, S.; Matthews, R.; Paul, G.

    1996-09-01

    The Do-It-Now (DIN) building maintenance system is proposed to reduce the cost of routine building maintenance and repairs and to improve customer satisfaction with maintenance services. DIN uses a team approach to periodically inspect buildings and provide maintenance services on the spot. It emphasizes communications between the customers and the craftspeople performing the work. The system was designed using a reengineering approach that characterized the existing maintenance work control system, analyzed comparable systems in other DOE laboratories, envisioned an ideal system, and proposed a workable, testable system for initial implementation. At each stage, input was solicited from customer representatives and Facilities management to ensure meeting customer requirements with an implementable system.

  2. Impacts of changing atmospheric deposition chemistry on nitrogen and phosphorus loading to Ganga River (India).

    PubMed

    Pandey, Jitendra; Singh, Anand V; Singh, Ashima; Singh, Rachna

    2013-08-01

    Investigations on atmospheric deposition (AD) and water chemistry along a 35 km stretch of Ganga River indicated that although N:P stoichiometry of AD did not change, there were over 1.4-2.0 fold increase in AD-NO₃⁻, AD-NH₄⁺ and AD-PO₄³⁻ overtime. Concentration of dissolved inorganic-N (DIN) in river showed significant positive correlations with AD-NO₃⁻ and runoff DIN. Similarly, dissolved reactive-P (DRP) in river showed significant positive correlation with AD-PO₄³⁻ and runoff DRP. The study shows that AD has become an important source of N and P input to Ganga River. PMID:23700007

  3. Abiotic factors influencing biomass accumulation of green tide causing Ulva spp. on Pyropia culture rafts in the Yellow Sea, China.

    PubMed

    Keesing, John K; Liu, Dongyan; Shi, Yajun; Wang, Yujue

    2016-04-15

    Annually recurrent green-tides in the Yellow Sea have been shown to result from direct disposal into the sea of fouling Ulva from Pyropia aquaculture. The role abiotic factors play in Ulva biomass accumulation on rafts was studied to find ways to mitigate this problem. Dissolved inorganic nitrogen (DIN) was very high at all sites, but the highest Ulva biomass was associated with the lowest DIN and anthropogenic N. Under luxuriant background nutrient conditions, variability in temperature and periods of emersion, rather than pH, light and salinity determined Ulva biomass. Two dominant species of Ulva displayed differing tolerances to temperature and desiccation which helped explain why Ulva prolifera dominates floating green-tides. Rather than trying to mitigate green-tides only by reducing nutrient pollution, an earlier harvest of Pyropia in southern Jiangsu Province especially before temperatures increase greatly above 10°C during April, could reduce the biomass of U. prolifera disposed from rafts. PMID:26936121

  4. Khayyam [al-Khayyam], Omar [Abu ol-Fath ebn-Ebrahim `Omar ol-Khayyami of Nishapur] (c. 1044-c. 1123)

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    Poet, mathematician, astronomer, born in Nishapur, Persia (now Iran), to a family of Arabic tent makers (a translation of his name), an outstanding mathematician and astronomer. The Saljuq Sultan, Malikshah Jalal al-Din, appointed him to the observatory at Ray around 1074 to determine the solar calendar, as an aid to tax collection. Khayyam developed a calendar called Al-Tarikh-al-Jalali, which h...

  5. The role of a trigeminal sensory nucleus in the initiation of locomotion.

    PubMed

    Buhl, Edgar; Roberts, Alan; Soffe, Stephen R

    2012-05-15

    While we understand how stimuli evoke sudden, ballistic escape responses, like fish fast-starts, a precise pathway from sensory stimulation to the initiation of rhythmic locomotion has not been defined for any vertebrate. We have now asked how head skin stimuli evoke swimming in hatchling frog tadpoles. Whole-cell recordings and dye filling revealed a nucleus of ∼20 trigeminal interneurons (tINs) in the hindbrain, at the level of the auditory nerve, with long, ipsilateral, descending axons. Stimulation of touch-sensitive trigeminal afferents with receptive fields anywhere on the head evoked large, monosynaptic EPSPs (∼5-20 mV) in tINs, at mixed AMPAR/NMDAR synapses. Following stimuli sufficient to elicit swimming, tINs fired up to six spikes, starting 4-8 ms after the stimulus. Paired whole-cell recordings showed that tINs produce small (∼2-6 mV), monosynaptic, glutamatergic EPSPs in the hindbrain reticulospinal neurons (descending interneurons, dINs) that drive swimming. Modelling suggested that summation of EPSPs from 18-24 tINs can make 20-50% of dINs fire. We conclude that: brief activity in a few sensory afferents is amplified by recruitment of many tINs; these relay summating excitation to hindbrain reticulospinal dINs; dIN firing then initiates activity for swimming on the stimulated side. During fictive swimming, tINs are depolarised and receive rhythmic inhibition but do not fire. Our recordings demonstrate a neuron-by-neuron pathway from head skin afferents to the reticulospinal neurons and motoneurons that drive locomotion in a vertebrate. This direct pathway, which has an important amplifier function, implies a simple origin for the complex routes to initiate locomotion in higher vertebrates.

  6. Virtual management of radiology examinations in the virtual radiology environment using common object request broker architecture services.

    PubMed

    Martinez, R; Rozenblit, J; Cook, J F; Chacko, A K; Timboe, H L

    1999-05-01

    In the Department of Defense (DoD), US Army Medical Command is now embarking on an extremely exciting new project--creating a virtual radiology environment (VRE) for the management of radiology examinations. The business of radiology in the military is therefore being reengineered on several fronts by the VRE Project. In the VRE Project, a set of intelligent agent algorithms determine where examinations are to routed for reading bases on a knowledge base of the entire VRE. The set of algorithms, called the Meta-Manager, is hierarchical and uses object-based communications between medical treatment facilities (MTFs) and medical centers that have digital imaging network picture archiving and communications systems (DIN-PACS) networks. The communications is based on use of common object request broker architecture (CORBA) objects and services to send patient demographics and examination images from DIN-PACS networks in the MTFs to the DIN-PACS networks at the medical centers for diagnosis. The Meta-Manager is also responsible for updating the diagnosis at the originating MTF. CORBA services are used to perform secure message communications between DIN-PACS nodes in the VRE network. The Meta-Manager has a fail-safe architecture that allows the master Meta-Manager function to float to regional Meta-Manager sites in case of server failure. A prototype of the CORBA-based Meta-Manager is being developed by the University of Arizona's Computer Engineering Research Laboratory using the unified modeling language (UML) as a design tool. The prototype will implement the main functions described in the Meta-Manager design specification. The results of this project are expected to reengineer the process of radiology in the military and have extensions to commercial radiology environments. PMID:10342205

  7. Virtual management of radiology examinations in the virtual radiology environment using common object request broker architecture services.

    PubMed

    Martinez, R; Rozenblit, J; Cook, J F; Chacko, A K; Timboe, H L

    1999-05-01

    In the Department of Defense (DoD), US Army Medical Command is now embarking on an extremely exciting new project--creating a virtual radiology environment (VRE) for the management of radiology examinations. The business of radiology in the military is therefore being reengineered on several fronts by the VRE Project. In the VRE Project, a set of intelligent agent algorithms determine where examinations are to routed for reading bases on a knowledge base of the entire VRE. The set of algorithms, called the Meta-Manager, is hierarchical and uses object-based communications between medical treatment facilities (MTFs) and medical centers that have digital imaging network picture archiving and communications systems (DIN-PACS) networks. The communications is based on use of common object request broker architecture (CORBA) objects and services to send patient demographics and examination images from DIN-PACS networks in the MTFs to the DIN-PACS networks at the medical centers for diagnosis. The Meta-Manager is also responsible for updating the diagnosis at the originating MTF. CORBA services are used to perform secure message communications between DIN-PACS nodes in the VRE network. The Meta-Manager has a fail-safe architecture that allows the master Meta-Manager function to float to regional Meta-Manager sites in case of server failure. A prototype of the CORBA-based Meta-Manager is being developed by the University of Arizona's Computer Engineering Research Laboratory using the unified modeling language (UML) as a design tool. The prototype will implement the main functions described in the Meta-Manager design specification. The results of this project are expected to reengineer the process of radiology in the military and have extensions to commercial radiology environments.

  8. Effects of watershed densities of animal feeding operations on nutrient concentrations and estrogenic activity in agricultural streams.

    PubMed

    Ciparis, Serena; Iwanowicz, Luke R; Voshell, J Reese

    2012-01-01

    Application of manures from animal feeding operations (AFOs) as fertilizer on agricultural land can introduce nutrients and hormones (e.g. estrogens) to streams. A landscape-scale study was conducted in the Shenandoah River watershed (Virginia, USA) in order to assess the relationship between densities of AFOs in watersheds of agricultural streams and in-stream nutrient concentrations and estrogenic activity. The effect of wastewater treatment plants (WWTPs) on nutrients and estrogenic activity was also evaluated. During periods of high and low flow, dissolved inorganic nitrogen (DIN) and orthophosphate (PO(4)-P) concentrations were analyzed and estrogens/estrogenic compounds were extracted and quantified as17β-estradiol equivalents (E2Eq) using a bioluminescent yeast estrogen screen. Estrogenic activity was measurable in the majority of collected samples, and 20% had E2Eq concentrations >1 ng/L. Relatively high concentrations of DIN (>1000 μg/L) were also frequently detected. During all sampling periods, there were strong relationships between watershed densities of AFOs and in-stream concentrations of DIN (R(2) = 0.56-0.81) and E2Eq (R(2) = 0.39-0.75). Relationships between watershed densities of AFOs and PO(4)-P were weaker, but were also significant (R(2) = 0.27-0.57). When combined with the effect of watershed AFO density, streams receiving WWTP effluent had higher concentrations of PO(4)-P than streams without WWTP discharges, and PO(4)-P was the only analyte with a consistent relationship to WWTPs. The results of this study suggest that as the watershed density of AFOs increases, there is a proportional increase in the potential for nonpoint source pollution of agricultural streams and their receiving waters by nutrients, particularly DIN, and compounds that can cause endocrine disruption in aquatic organisms.

  9. A Connector Between Active Laboratory Probes and Computer Interfaces of Different Brands

    NASA Astrophysics Data System (ADS)

    Hui, Kaleonui J.; Coney, John P.; Binder, P.-M.

    2016-04-01

    In PASCO's Technical Article # 763, it is stated that "PASCO [also] makes sensors with an 8-pin DIN connector. These sensors cannot be used with the Vernier interfaces, as they have different power requirements." Recently we had the need to make such connections in a 10-station freshman lab. Since the Vernier input is a 6-way BT 631A plug also used in TI and Casio equipment, our experience may be of interest to a broad audience of lab coordinators.

  10. Testing the AUDI2000 colour-difference formula for solid colours using some visual datasets with usefulness to automotive industry

    NASA Astrophysics Data System (ADS)

    Martínez-García, Juan; Melgosa, Manuel; Gómez-Robledo, Luis; Li, Changjun; Huang, Min; Liu, Haoxue; Cui, Guihua; Luo, M. Ronnier; Dauser, Thomas

    2013-11-01

    Colour-difference formulas are tools employed in colour industries for objective pass/fail decisions of manufactured products. These objective decisions are based on instrumental colour measurements which must reliably predict the subjective colour-difference evaluations performed by observers' panels. In a previous paper we have tested the performance of different colour-difference formulas using the datasets employed at the development of the last CIErecommended colour-difference formula CIEDE2000, and we found that the AUDI2000 colour-difference formula for solid (homogeneous) colours performed reasonably well, despite the colour pairs in these datasets were not similar to those typically employed in the automotive industry (CIE Publication x038:2013, 465-469). Here we have tested again AUDI2000 together with 11 advanced colour-difference formulas (CIELUV, CIELAB, CMC, BFD, CIE94, CIEDE2000, CAM02-UCS, CAM02-SCD, DIN99d, DIN99b, OSA-GP-Euclidean) for three visual datasets we may consider particularly useful to the automotive industry because of different reasons: 1) 828 metallic colour pairs used to develop the highly reliable RIT-DuPont dataset (Color Res. Appl. 35, 274-283, 2010); 2) printed samples conforming 893 colour pairs with threshold colour differences (J. Opt. Soc. Am. A 29, 883-891, 2012); 3) 150 colour pairs in a tolerance dataset proposed by AUDI. To measure the relative merits of the different tested colour-difference formulas, we employed the STRESS index (J. Opt. Soc. Am. A 24, 1823-1829, 2007), assuming a 95% confidence level. For datasets 1) and 2), AUDI2000 was in the group of the best colour-difference formulas with no significant differences with respect to CIE94, CIEDE2000, CAM02-UCS, DIN99b and DIN99d formulas. For dataset 3) AUDI2000 provided the best results, being statistically significantly better than all other tested colour-difference formulas.

  11. A novel computer software for the evaluation of dynamic visual acuity

    PubMed Central

    Quevedo, Lluïsa; Aznar-Casanova, José Antonio; Merindano-Encina, Dolores; Cardona, Genís; Solé-Fortó, Joan

    2012-01-01

    Purpose Dynamic visual acuity (DVA) is defined as the ability to discriminate fine details in a moving target. Albeit a growing interest in DVA, there is a lack of standardized, validated instrumentation and procedures for the assessment of this visual function parameter. The aim of the present study was to analyze qualitative construct validity and test–retest reliability of a novel, computer-assisted instrument (DinVA 3.0) for the measurement of DVA. Methods Two different experiments are presented, involving the participation of 33 subjects. The first experiment aimed at testing qualitative construct validity of the DinVA 3.0 by comparing the outcome of a series of trials consisting in different speeds, contrasts and trajectories of the target stimuli with those reported in the literature. The second experiment assessed test–retest reliability by repeating a series of trials at three different time intervals, at maximum target stimuli contrast and either high or low speed configurations. Results The results of the first experiment gave support to the qualitative construct validity of DinVA 3.0, as the DVA scores were found to be modulated by the speed of the moving target (high speeds yielded lower DVA), contrast (high contrast resulted in better DVA) and trajectory (DVA was better at horizontal rather than oblique trajectories). Test–retest reliability was found to be good, with a small insignificant trend towards improvement with learning. Conclusion The DinVA 3.0 proved to be a valid and reliable instrument for the assessment of DVA and may be considered a promising tool for both clinicians and researchers.

  12. Effects of watershed densities of animal feeding operations on nutrient concentrations and estrogenic activity in agricultural streams

    USGS Publications Warehouse

    Ciparis, S.; Iwanowicz, L.R.; Voshell, J.R.

    2012-01-01

    Application of manures from animal feeding operations (AFOs) as fertilizer on agricultural land can introduce nutrients and hormones (e.g. estrogens) to streams. A landscape-scale study was conducted in the Shenandoah River watershed (Virginia, USA) in order to assess the relationship between densities of AFOs in watersheds of agricultural streams and in-stream nutrient concentrations and estrogenic activity. The effect of wastewater treatment plants (WWTPs) on nutrients and estrogenic activity was also evaluated. During periods of high and low flow, dissolved inorganic nitrogen (DIN) and orthophosphate (PO 4-P) concentrations were analyzed and estrogens/estrogenic compounds were extracted and quantified as17??-estradiol equivalents (E2Eq) using a bioluminescent yeast estrogen screen. Estrogenic activity was measurable in the majority of collected samples, and 20% had E2Eq concentrations >1ng/L. Relatively high concentrations of DIN (>1000??g/L) were also frequently detected. During all sampling periods, there were strong relationships between watershed densities of AFOs and in-stream concentrations of DIN (R 2=0.56-0.81) and E2Eq (R 2=0.39-0.75). Relationships between watershed densities of AFOs and PO 4-P were weaker, but were also significant (R 2=0.27-0.57). When combined with the effect of watershed AFO density, streams receiving WWTP effluent had higher concentrations of PO 4-P than streams without WWTP discharges, and PO 4-P was the only analyte with a consistent relationship to WWTPs. The results of this study suggest that as the watershed density of AFOs increases, there is a proportional increase in the potential for nonpoint source pollution of agricultural streams and their receiving waters by nutrients, particularly DIN, and compounds that can cause endocrine disruption in aquatic organisms. ?? 2011 Elsevier B.V.

  13. Effects of watershed densities of animal feeding operations on nutrient concentrations and estrogenic activity in agricultural streams

    USGS Publications Warehouse

    Ciparis, Serena; Iwanowicz, Luke R.; Voshell, J. Reese

    2012-01-01

    Application of manures from animal feeding operations (AFOs) as fertilizer on agricultural land can introduce nutrients and hormones (e.g. estrogens) to streams. A landscape-scale study was conducted in the Shenandoah River watershed (Virginia, USA) in order to assess the relationship between densities of AFOs in watersheds of agricultural streams and in-stream nutrient concentrations and estrogenic activity. The effect of wastewater treatment plants (WWTPs) on nutrients and estrogenic activity was also evaluated. During periods of high and low flow, dissolved inorganic nitrogen (DIN) and orthophosphate (PO4-P) concentrations were analyzed and estrogens/estrogenic compounds were extracted and quantified as17β-estradiol equivalents (E2Eq) using a bioluminescent yeast estrogen screen. Estrogenic activity was measurable in the majority of collected samples, and 20% had E2Eq concentrations > 1 ng/L. Relatively high concentrations of DIN (> 1000 μg/L) were also frequently detected. During all sampling periods, there were strong relationships between watershed densities of AFOs and in-stream concentrations of DIN (R2 = 0.56–0.81) and E2Eq (R2 = 0.39–0.75). Relationships between watershed densities of AFOs and PO4-P were weaker, but were also significant (R2 = 0.27–0.57). When combined with the effect of watershed AFO density, streams receiving WWTP effluent had higher concentrations of PO4-P than streams without WWTP discharges, and PO4-P was the only analyte with a consistent relationship to WWTPs. The results of this study suggest that as the watershed density of AFOs increases, there is a proportional increase in the potential for nonpoint source pollution of agricultural streams and their receiving waters by nutrients, particularly DIN, and compounds that can cause endocrine disruption in aquatic organisms.

  14. Christopher Lasch and Prairie Populism

    ERIC Educational Resources Information Center

    Lauck, Jon K.

    2012-01-01

    Christopher Lasch was born in Omaha in 1932. By the end of his life, cut short at age sixty-one, he had become one of the most famous intellectuals in the world. During his life of active writing from the time of the early Cold War until the fall of the Soviet Union, Lasch's distinctive voice pierced through the din of the nation's noisy political…

  15. Correlation of in vivo relative bioavailability to in vitro bioaccessibility for arsenic in household dust from China and its implication for human exposure assessment.

    PubMed

    Li, Hong-Bo; Li, Jie; Juhasz, Albert L; Ma, Lena Q

    2014-12-01

    Incidental ingestion of household dust is an important arsenic (As) exposure pathway for children. However, compared to soils, assessment of As relative bioavailability (RBA) in household dust is limited. In this study, As-RBA in 12 household dust samples (7–38 mg kg(–1)) was measured using an in vivo mouse model and compared to As bioaccessibility determined using 4 assays [Solubility Bioaccessibility Research Consortium method (SBRC), in vitro gastrointestinal method (IVG), Deutsches Institut für Normunge.V. method (DIN), and physiologically based extraction test (PBET)]. Arsenic RBA ranged from 21.8 ± 1.6 to 85.6 ± 7.2% with samples containing low Fe and high total organic carbon content having higher As-RBA. Strong in vivo–in vitro correlations (IVIVC) were found between As-RBA and As bioaccessibility for SBRC and DIN (r2 = 0.63–0.85), but weaker ones were obtained for IVG and PBET (r2 = 0.29–0.55). The developed IVIVC for SBRC and DIN were used to calculate As-RBA based on As bioaccessibility for an additional 12 household dust samples. Although As bioaccessibility differed significantly (up to 7.7-fold) based on in vitro methods, predicted As-RBA was less variable (up to 3.0-fold) when calculated using As bioaccessibility data and the corresponding IVIVC. Our data suggested that both SBRC and DIN had potential to assess As bioavailability in household dust samples; however, additional research is needed.

  16. Quantification of the impact of macrophytes on oxygen dynamics and nitrogen retention in a vegetated lowland river

    NASA Astrophysics Data System (ADS)

    Desmet, N. J. S.; Van Belleghem, S.; Seuntjens, P.; Bouma, T. J.; Buis, K.; Meire, P.

    When macrophytes are growing in the river, the vegetation induces substantial changes to the water quality. Some effects are the result of direct interactions, such as photosynthetic activity or nutrient uptake, whereas others may be attributed to indirect effects of the water plants on hydrodynamics and river processes. This research focused on the direct effect of macrophytes on oxygen dynamics and nutrient cycling. Discharge, macrophyte biomass density, basic water quality, dissolved oxygen and nutrient concentrations were in situ monitored throughout the year in a lowland river (Nete catchment, Belgium). In addition, various processes were investigated in more detail in multiple ex situ experiments. The field and aquaria measurement results clearly demonstrated that aquatic plants can exert considerable impact on dissolved oxygen dynamics in a lowland river. When the river was dominated by macrophytes, dissolved oxygen concentrations varied from 5 to 10 mg l -1. Considering nutrient retention, it was shown that the investigated in-stream macrophytes could take up dissolved inorganic nitrogen (DIN) from the water column at rates of 33-50 mg N kgdry matter-1 h. And DIN fluxes towards the vegetation were found to vary from 0.03 to 0.19 g N ha -1 h -1 in spring and summer. Compared to the measured changes in DIN load over the river stretch, it means that about 3-13% of the DIN retention could be attributed to direct nitrogen uptake from the water by macrophytes. Yet, the role of macrophytes in rivers should not be underrated as aquatic vegetation also exerts considerable indirect effects that may have a greater impact than the direct fixation of nutrients into the plant biomass.

  17. Linking benthic community structure to terrestrial runoff and upwelling in the coral reefs of northeastern Hainan Island

    NASA Astrophysics Data System (ADS)

    Li, Xiubao; Wang, Daoru; Huang, Hui; Zhang, Jing; Lian, Jiansheng; Yuan, Xiangcheng; Yang, Jianhui; Zhang, Guoseng

    2015-04-01

    Near-shore coral reefs in northeastern Hainan Island are close to river mouths and aquaculture ponds, and also located at the center of the Qiongdong Upwelling (QDU). However, it is still unclear how terrestrial runoff and upwelling influence the community composition and spatial distribution of the benthos. During three cruises in 2010 and 2011 in Wenchang, northeastern Hainan Island, we determined a subset of environmental parameters in seawater (e.g. temperature, salinity, DO, dissolved inorganic nutrient (DIN), turbidity and transparency) and macroalgal δ15N and investigated the benthic communities (e.g. live coral cover, coral species richness, juvenile coral density, macroalgal cover and coverage of calcified algae) by video transect and visual census techniques at 10 stations (i.e. 1S-6D). The results showed that the QDU has influenced the reef waters in Wenchang. In 2011, the upwelling started in early May, peaked in July and disappeared in September and most upwelling events lasted for 1-2 weeks between May and July. The results also demonstrated that the reef water was nutrient enriched. Stations close to the river mouth and aquaculture ponds had higher levels of DIN and a higher percentage of ammonia in DIN, and there was consistently lower live coral cover, juvenile coral density and higher macroalgal cover. At some stations in this study, live coral cover was negatively correlated with macroalgal cover (i.e. 2S-6D). Live coral cover, species richness, and juvenile coral density all increased with the distance away from the river outlet and decreased with the rise of DIN. These results suggest that terrestrial runoff and upwelling stimulate nutrient enrichment, and that overgrowing macroalgae has an important influence on the coral communities in northeastern Hainan Island.

  18. Entropía de la información: una herramienta útil

    NASA Astrophysics Data System (ADS)

    Cincotta, P.

    En este trabajo se presenta una muy breve introducción al concepto de Entropía de la Información y se muestran distintas aplicaciones de una misma técnica para estudiar problemas tan variados como la determinación de periodicidad en una serie de tiempo arbitraria o de estimar el grado de caoticidad de una trayectoria en un sistema dinámico de N grados de libertad.

  19. Export of nitrogen from catchments within a temperate forest: Evidence for a unifying mechanism regulated by variable source area dynamics

    NASA Astrophysics Data System (ADS)

    Creed, I. F.; Band, L. E.

    1998-11-01

    Considerable variation in the export of dissolved inorganic nitrogen (DIN) and dissolved organic nitrogen (DON) was observed among catchments located within an old-growth sugar maple forest in central Ontario. Although discharge was a strong predictor of N-export, rates of export were variable for each catchment, ranging from -50% to +50% from the catchment-average response for DIN and -25% to +25% from the catchment-average response for DON. Among the catchments, a unifying flushing behavior was apparent for NO3--N, the dominant form of DIN in the discharge waters, providing a basis for explaining the variation in the export of DIN. Flushing occurs when a water table rises to the soil surface with subsequent mobilization of nutrients stored near or at the soil surface to surface waters. Catchment-specific flushing behaviors were captured in "flushing" characteristic time constants, defined as the time interval required for a decline in N concentrations in discharge waters toe-l (37%) of their initial concentration. Variation in flushing behavior was linked to variation in N export; catchments with short flushing times (interpreted as catchments with source areas that are less variable) were observed to export less N than catchments with long flushing times (source areas that are more variable). A hypothesis was formulated in which catchment topography and its influence on variable source area dynamics accounts for variation in flushing behavior, hence variation in the export of NO3--N among the catchments. The implication of this hypothesis is that to predict accurately the export of NO3--N from catchments within a landscape, we need first to consider the influence of the topographic complexity of the catchments. Our understanding of the mechanisms of processing and export of DON is not sufficient for accurate prediction at this point, highlighting the need for additional research on DON.

  20. Dissolved inorganic nitrogen pools and surface flux under different brackish marsh vegetation types, common reed (Phragmites australis) and salt hay (Spartina patens)

    USGS Publications Warehouse

    Windham-Myers, L.

    2005-01-01

    The current expansion of Phragmites australis into the high marsh shortgrass (Spartina patens, Distichlis spicata) communities of eastern U.S. salt marshes provided an opportunity to identify the influence of vegetation types on pools and fluxes of dissolved inorganic nitrogen (DIN). Two brackish tidal marshes of the National Estuarine Research Reserve system were examined, Piermont Marsh of the Hudson River NERR in New York and Hog Island in the Jacques Coustaeu NERR of New Jersey. Pools of DIN in porewater and rates of DIN surface flux were compared in replicated pairs of recently-expanded P. australis and neighboring S. patens-dominated patches on the high marsh surface. Both marshes generally imported nitrate (NO3-) and exported ammonium (NH4+), such that overall DIN was exported. No differences in surface exchange of NO3- or NH4+ were observed between vegetation types. Depth-averaged porewater NH4+ concentrations over the entire growing season were 56% lower under P. australis than under S. patens (average 1.4 vs. 3.2 mg NH4+ L-1) with the most profound differences in November. Porewater profiles showed an accumulation of NH4+ at depth in S. patens and constant low concentrations in P. australis from the soil surface to 50 cm depth, with no significant differences in porewater salinity. Despite these profound differences in porewater, NH 4+ diffusion from soils of P. australis and S. patens were not measurably different, were similar to other published rates, and were well below estimated rates based on passive diffusion alone. Rapid adsorption and uptake by litter and microbes in surface soils of both communities may buffer NH4+ loss to flooding tides in both communities, thereby reducing the impact of P. australis invasion on NH4+ flux to flooding waters. ?? Springer 2005.

  1. Dissolved inorganic P and N input into the Yangtze estuary: ecological response

    NASA Astrophysics Data System (ADS)

    Xu, H.

    2013-12-01

    The Yangtze estuary has received more environmental hazards in the past decades. For instance, the occurrences of red tides have increased from 8 times to >100 times from 1980s to 2000s. Large-scale blooming can cover an estuarine water area of >1000 km2. There are many factors that can drive the algae blooming, such as temperature, illumination, salinity and nutrients flux, etc. However, it seems that the riverine dissolved inorganic phosphate (DIP) and nitrogen (DIN) has been increased dramatically over the last half-century in the Yangtze estuary. Therefore, the DIP and DIN are thought to be the predominant factor in deteriorating estuarine eco-health. This study has calculated the annual DIP into the Yangtze estuary, increasing from 7.6 x 103 ton in 1972 to 35 x 103 ton in 2007, and DIN from 0.2 x 106 ton to 1.33 x 106 ton in the same period. Our evidence shows that the riverine nutrients were dominated by fertilizer in decades ago, but it has been changed to domestic sewage since 2000. Overloading nutrients have directly changed the algae species in the estuarine waters, i.e. from Skeletonema costatum to Prorocentrum donghaiens, which enlarges the time duration and distribution scale of algae blooming. Sediment concentration which can absorb considerable DIP and DIN, is to be largely lessened in the estuarine waters due to the Three-Gorges damming. In this study, we are applying the muddy-LOICZ model to help estimate the role of SSC for nutrients distribution after damming. Our preliminary results have proved ca. 20% DIP that will increase in response to reduction of SSC in future. This will exert a significant impact on the ecosystem of the Yangtze estuary. The results would provide insight to a sound coastal water management.

  2. Rapid decline of dissolved nitrogen in Finnish lakes

    NASA Astrophysics Data System (ADS)

    Rekolainen, Seppo; Mitikka, Sari; Vuorenmaa, Jussi; Johansson, Matti

    2005-03-01

    Since 1960s, phosphorus (P) has been considered to be most often the limiting factor for algal growth in freshwater lakes. Due to that, pollution control measures have been targeted to reduce P loading to lakes. In many countries these efforts have been successful: the P loadings, particularly through municipal waste waters have been reduced substantially, which has resulted in reduced P concentration of lake waters, and improvements in ecological quality of numerous lakes. Nitrogen reductions in wastewater treatment plants have started only in very recent years, and usually only in cities along the seashore. Analysis of the long-term lake monitoring data in Finland show a sharp decline of dissolved inorganic nitrogen (DIN, expressed as a sum of NO 2-N, NO 3-N and NH 4-N) during the 1990s. Most of these lakes are oligotrophic lakes with low human impact. Due to this, the relative contribution of air-borne nitrogen loading (deposition directly to the lake surface) is often higher than in lakes located in densely populated or in intensive agricultural regions. The DIN deposition monitoring results show approximately a 40% reduction during the same period as the decreasing DIN trend is observed in lakes. These trends in deposition can probably be explained by reductions in nitrogen emissions in Europe, in connection to air pollution control conventions, and in Eastern Europe also in connection to economical collapse at the beginning of 1990s. In many of the lakes with a significant decreasing trend, DIN concentrations in late summer are approaching very low levels (<20 μg l -1), indicating that nitrogen is possibly limiting algal growth at least seasonally. The observed trends are an example of how pollution control measures may result in a quick response, in this case unexpected, though not necessarily undesirable.

  3. Sources, behaviors and degradation of dissolved organic matter in the East China Sea

    NASA Astrophysics Data System (ADS)

    Chen, Yan; Yang, Gui-Peng; Liu, Li; Zhang, Peng-Yan; Leng, Wei-Song

    2016-03-01

    Concentrations of dissolved organic carbon (DOC), dissolved inorganic nitrogen (DIN), dissolved organic nitrogen (DON) and its major compound classes-total hydrolysable amino acids (THAA) were measured at 4 cross-shelf transects of the East China Sea in July 2011. Surface concentrations of DOC, DIN, DON and THAA at the nearshore stations were mostly in excess of those found at the offshore sites, indicating either substantial autochthonous production or allochthonous inputs from the Changjiang River. The vertical distributions of DOC, DON and THAA showed similar trends with higher values in the surface layer, whereas the elevated concentrations of DIN were observed in the bottom layer. Major constituents of THAA presented in the study area were glycine, serine, alanine, glutamic acid, aspartic acid and valine. The mole percentages of neutral amino acids increased from surface water to bottom water, whereas acidic and hydroxy amino acids decreased with the water depth. Concentrations of DOC and THAA were negatively correlated to the ΔDIN values (the difference between the real concentration and theoretical concentration), respectively, indicating the coupling relation between dissolved organic matter (DOM) remineralization and nutrient regeneration in the water column. The C/N ratios in the water column exhibited different characteristics with elevated values appearing in the surface and bottom layers. Box and whisker plots showed that both degradation index (DI) values and THAA yields displayed a decreasing trend from the surface layer to the bottom layer, implying increasing degradation with the water depth. Our data revealed that glycine and alanine increased in relative abundance with decreasing DI, while tyrosine, valine, phenylalanine and isoleucine increased with increasing DI.

  4. Benthic nutrient fluxes in the Eastern Gotland Basin (Baltic Sea) with particular focus on microbial mat ecosystems

    NASA Astrophysics Data System (ADS)

    Noffke, A.; Sommer, S.; Dale, A. W.; Hall, P. O. J.; Pfannkuche, O.

    2016-06-01

    Benthic fluxes and water column distributions of dissolved inorganic nitrogen (DIN) and total dissolved phosphate (PO43 -) were measured in situ at 7 sites across a redox gradient from oxic to anoxic bottom waters in the Eastern Gotland Basin (Baltic Sea). The study area was divided into the oxic zone (60 to ca. 80 m water depth, O2 > 30 μM), the hypoxic transition zone (HTZ, ca. 80 to 120 m, O2 < 30 μM) and the deep anoxic and sulfidic basin (> ca. 120 m). Sediments in the HTZ were covered by mats of vacuolated sulfur bacteria. Ammonium (NH4+) fluxes in the deep basin and the HTZ were elevated at 0.6 mmol m- 2 d- 1 and 1 mmol m- 2 d- 1, respectively. Nitrate (NO3-) fluxes were directed into the sediment at all stations in the HTZ and were zero in the deep basin. PO43 - release was highest in the HTZ at 0.23 mmol m- 2 d- 1, with a further release of 0.2 mmol m- 2 d- 1 in the deep basin. Up-scaling the benthic fluxes to the Baltic Proper equals 109 kt yr- 1 of PO43 - and 266 kt yr- 1 of DIN. This is eight- and two-fold higher than the total external load of P (14 kt yr- 1) and DIN (140 kt yr- 1) in 2006 (HELCOM 2009b). The HTZ makes an important contribution to the internal nutrient loading in the Baltic Proper, releasing 70% of P (76 kt yr- 1) and 75% of DIN (200 kt yr- 1) despite covering only 51% of area.

  5. Observación solar desde el espacio, resultados recientes

    NASA Astrophysics Data System (ADS)

    Machado, M. E.

    Presentaremos un resumen de los resultados más recientes sobre la física del sol, obtenidos por medio del análisis de datos de satélites artificiales como el Yohkoh, SOHO y COMPTON/GRO. En particular, nos referiremos a la acción y dinámica de los campos magnéticos en la generación de fenómenos activos y el calentamiento coronal.

  6. Surface deformation of Taipei basin detected by Differential SAR Interferometry

    NASA Astrophysics Data System (ADS)

    Chen, Y.; Chang, C.; Yen, J.; Lin, M.

    2006-12-01

    Taiwan island is located between the southeastern periphery of the Eurasian plate and the Philippine Sea plate. The two converging plates produced very active tectonics, and can be seen by the high seismicity and deformation rate. Taipei, the highest populated area, center of politics, and economics in Taiwan, is in Taipei basin at the northern part of the island. There are several faults in and surrounding the basin, and the city is threatened with a high geological hazard potential that we should keep monitoring the crustal deformation to prevent and mitigate the disaster effect. The aims of our study is to apply the DInSAR technique to determine the surface deformation of Taipei basin area, and discussing the relation between the manifestation of deformation and the tectonically active region, Shanjiao fault. In the past few years, Differential SAR Interferometry (DInSAR) has been proved to be a powerful technique for monitoring the neotectonic activities and natural hazards. High spatial sampling rate of DInSAR technique allows studies of surface deformations with centimeter accuracy. In this area, we used ERS-1/2 SAR images acquired from 1993 to 2005 to generate 10 differential interferograms and processed the data using DIAPASON developed by CNES and SRTM global DEM.From our results, the deformation rate in Taipei is generally high in the western end of the basin along the Shanjiao fault and decrease eastward, while the subsidence center often appeared in the center of the Taipei basin. The neotectonic activity of the Shanjiao fault appeared to be insignificant by itself but it seemed to separate the subsiding basin from the surrounding areas. Further comparison between our DInSAR results and isopach of the Taipei basin revealed that the subsidence centers appeared in the interferograms did not coincide with the location where the sediments are thickest. Our results from differential interferometry will be compared to other geodetic measurements such as the

  7. Characterization of quantum circulant networks having perfect state transfer

    NASA Astrophysics Data System (ADS)

    Bašić, Milan

    2013-01-01

    In this paper we answer the question of when circulant quantum spin networks with nearest-neighbor couplings can give perfect state transfer. The network is described by a circulant graph G, which is characterized by its circulant adjacency matrix A. Formally, we say that there exists a perfect state transfer (PST) between vertices {a,bin V(G)} if | F( τ) ab | = 1, for some positive real number τ, where F( t) = exp(i At). Saxena et al. (Int J Quantum Inf 5:417-430, 2007) proved that | F( τ) aa | = 1 for some {ain V(G)} and {tauin {R}^+} if and only if all eigenvalues of G are integer (that is, the graph is integral). The integral circulant graph ICG n ( D) has the vertex set Z n = {0, 1, 2, . . . , n - 1} and vertices a and b are adjacent if {gcd(a-b,n)in D} , where {D subseteq {d : d mid n, 1 ≤ d < n}} . These graphs are highly symmetric and have important applications in chemical graph theory. We show that ICG n ( D) has PST if and only if {nin 4{N}} and {D=widetilde{D_3} \\cup D_2\\cup 2D_2\\cup 4D_2|cup {n/2^a}} , where {widetilde{D_3}={din D | n/din 8{N}}, D_2= {din D | n/din 8{N}+4}{setminus}{n/4}} and {ain{1,2}} . We have thus answered the question of complete characterization of perfect state transfer in integral circulant graphs raised in Angeles-Canul et al. (Quantum Inf Comput 10(3&4):0325-0342, 2010). Furthermore, we also calculate perfect quantum communication distance (distance between vertices where PST occurs) and describe the spectra of integral circulant graphs having PST. We conclude by giving a closed form expression calculating the number of integral circulant graphs of a given order having PST.

  8. A-Differential Synthetic Aperture Radar Interferometry analysis of a Deep Seated Gravitational Slope Deformation occurring at Bisaccia (Italy).

    PubMed

    Di Martire, Diego; Novellino, Alessandro; Ramondini, Massimo; Calcaterra, Domenico

    2016-04-15

    This paper presents the results of an investigation on a Deep Seated Gravitational Slope Deformation (DSGSD), previously only hypothesized by some authors, affecting Bisaccia, a small town located in Campania region, Italy. The study was conducted through the integration of conventional methods (geological-geomorphological field survey, air-photo interpretation) and an Advanced-Differential Interferometry Synthetic Aperture Radar (A-DInSAR) technique. The DSGSD involves a brittle lithotype (conglomerates of the Ariano Irpino Supersynthem) resting over a Structurally Complex Formation (Varycoloured Clays of Calaggio Formation). At Bisaccia, probably as a consequence of post-cyclic recompression phenomena triggered by reiterated seismic actions, the rigid plate made up of conglomeratic sediments resulted to be split in five portions, showing different rates of displacements, whose deformations are in the order of some centimeter/year, thus inducing severe damage to the urban settlement. A-DInSAR techniques confirmed to be a reliable tool in monitoring slow-moving landslides. In this case 96 ENVIronmental SATellite-Advanced Synthetic Aperture Radar (ENVISAT-ASAR) images, in ascending and descending orbits, have been processed using SUBSOFT software, developed by the Remote Sensing Laboratory (RSLab) group from the Universitat Politècnica de Catalunya (UPC). The DInSAR results, coupled with field survey, supported the analysis of the instability mechanism and confirmed the historical record of the movements already available for the town.

  9. A-Differential Synthetic Aperture Radar Interferometry analysis of a Deep Seated Gravitational Slope Deformation occurring at Bisaccia (Italy).

    PubMed

    Di Martire, Diego; Novellino, Alessandro; Ramondini, Massimo; Calcaterra, Domenico

    2016-04-15

    This paper presents the results of an investigation on a Deep Seated Gravitational Slope Deformation (DSGSD), previously only hypothesized by some authors, affecting Bisaccia, a small town located in Campania region, Italy. The study was conducted through the integration of conventional methods (geological-geomorphological field survey, air-photo interpretation) and an Advanced-Differential Interferometry Synthetic Aperture Radar (A-DInSAR) technique. The DSGSD involves a brittle lithotype (conglomerates of the Ariano Irpino Supersynthem) resting over a Structurally Complex Formation (Varycoloured Clays of Calaggio Formation). At Bisaccia, probably as a consequence of post-cyclic recompression phenomena triggered by reiterated seismic actions, the rigid plate made up of conglomeratic sediments resulted to be split in five portions, showing different rates of displacements, whose deformations are in the order of some centimeter/year, thus inducing severe damage to the urban settlement. A-DInSAR techniques confirmed to be a reliable tool in monitoring slow-moving landslides. In this case 96 ENVIronmental SATellite-Advanced Synthetic Aperture Radar (ENVISAT-ASAR) images, in ascending and descending orbits, have been processed using SUBSOFT software, developed by the Remote Sensing Laboratory (RSLab) group from the Universitat Politècnica de Catalunya (UPC). The DInSAR results, coupled with field survey, supported the analysis of the instability mechanism and confirmed the historical record of the movements already available for the town. PMID:26849321

  10. The generation of antiphase oscillations and synchrony by a rebound-based vertebrate central pattern generator.

    PubMed

    Li, Wen-Chang; Merrison-Hort, Robert; Zhang, Hong-Yan; Borisyuk, Roman

    2014-04-23

    Many neural circuits are capable of generating multiple stereotyped outputs after different sensory inputs or neuromodulation. We have previously identified the central pattern generator (CPG) for Xenopus tadpole swimming that involves antiphase oscillations of activity between the left and right sides. Here we analyze the cellular basis for spontaneous left-right motor synchrony characterized by simultaneous bursting on both sides at twice the swimming frequency. Spontaneous synchrony bouts are rare in most tadpoles, and they instantly emerge from and switch back to swimming, most frequently within the first second after skin stimulation. Analyses show that only neurons that are active during swimming fire action potentials in synchrony, suggesting both output patterns derive from the same neural circuit. The firing of excitatory descending interneurons (dINs) leads that of other types of neurons in synchrony as it does in swimming. During synchrony, the time window between phasic excitation and inhibition is 7.9 ± 1 ms, shorter than that in swimming (41 ± 2.3 ms). The occasional, extra midcycle firing of dINs during swimming may initiate synchrony, and mismatches of timing in the left and right activity can switch synchrony back to swimming. Computer modeling supports these findings by showing that the same neural network, in which reciprocal inhibition mediates rebound firing, can generate both swimming and synchrony without circuit reconfiguration. Modeling also shows that lengthening the time window between phasic excitation and inhibition by increasing dIN synaptic/conduction delay can improve the stability of synchrony.

  11. The transcription elongation factor NusA is required for stress-induced mutagenesis in Escherichia coli.

    PubMed

    Cohen, Susan E; Walker, Graham C

    2010-01-12

    Stress-induced mutagenesis describes the accumulation of mutations that occur in nongrowing cells, in contrast to mutagenesis that occurs in actively dividing populations, and has been referred to as stationary-phase or adaptive mutagenesis. The most widely studied system for stress-induced mutagenesis involves monitoring the appearance of Lac(+) revertants of the strain FC40 under starvation conditions in Escherichia coli. The SOS-inducible translesion DNA polymerase DinB plays an important role in this phenomenon. Loss of DinB (DNA pol IV) function results in a severe reduction of Lac(+) revertants. We previously reported that NusA, an essential component of elongating RNA polymerases, interacts with DinB. Here we report our unexpected observation that wild-type NusA function is required for stress-induced mutagenesis. We present evidence that this effect is unlikely to be due to defects in transcription of lac genes but rather is due to an inability to adapt and mutate in response to environmental stress. Furthermore, we extended our analysis to the formation of stress-induced mutants in response to antibiotic treatment, observing the same striking abolition of mutagenesis under entirely different conditions. Our results are the first to implicate NusA as a crucial participant in the phenomenon of stress-induced mutagenesis. PMID:20036541

  12. [Seasonal variation and spatial distribution of nutrients and their relationships with harmful algal blooms in coastal area of the East China Sea].

    PubMed

    Zhang, Chuan-Song; Wang, Xiu-Lin; Shi, Xiao-Yong; Tang, Hong-Jie; Han, Xiu-Rong; Xin, Yu

    2007-11-01

    Based on the data from four cruises that carried out in the Changjiang River estuary and its adjacent areas from 2002-04 to 2003-02, the seasonal variation and spatial distribution of nutrients were analyzed, and the relationship between nutrients condition and the harmful algal blooms (HABs) was also discussed. Results showed that the annual average concentration of nutrient was (17.93 +/- 2.46) micromol x L(-1) for DIN, (0.59 +/- 0.11) micromol x L(-1) for PO4(3-) -P, (15.34 +/- 3.23) micromol x L(-1) for SiO3(2-) -Si, and the study area was in the state of eutrophication. The average concentration of nutrient showed a remarkable seasonal fluctuation with the higher value in autumn and winter and lower value in spring and summer. The spatial distribution of the nutrients was typically such that the concentrations of DIN, PO4(3-) -P and SiO3(2-) -Si decreased from inshore to offshore area, and the contours generally decreased rapidly in down-coast directions. DIN and SiO3(2-) -Si of the study area were largely contributed by Changjiang River diluted water and other terrigenous inputs, while PO4(3-) -P mainly by Changjiang River diluted water and the Taiwan Warm Current. The following HABs showed that its occurrences were usually laid in the areas with higher nutrients and lower total suspended particles (TSP). PMID:18290458

  13. Variations in seasonal phytoplankton assemblages as a response to environmental changes in the surface waters of a hypo saline coastal station along the Bhagirathi-Hooghly estuary.

    PubMed

    Choudhury, Avik Kumar; Pal, Ruma

    2011-08-01

    Due to the close proximity of the Bay of Bengal and the freshwater inflow of Bhagirathi-Hooghly, Diamond Harbour appeared as an important coastal station of the Bhagirathi-Hooghly estuary. The spatial and temporal composition and abundance of microphytoplankton species was examined in relation to physical and chemical surface water variables (i.e., salinity, nutrient, and temperature).The primary objective of the study was to observe the variations in phytoplankton species assemblages as a response to environmental variables. Hierarchical cluster analysis and non-metric multidimensional scaling were used to find out distinct seasonal groups based on the composition of phytoplankton. The results indicate that several key environmental factors like temperature, DIN content, and molar ratio of nutrients like DIN-DIP and DIN-DSi influenced seasonal phytoplankton assemblages within the estuary. The distribution of phytoplankton population showed two main groups where the blue-green and green algal populations favored the warmer conditions of summer and monsoon months, whereas the diatom population primarily flourished in the cooler months of autumn and winter. PMID:21069456

  14. Capturing the fingerprint of Etna volcano activity in gravity and satellite radar data

    PubMed Central

    Negro, Ciro Del; Currenti, Gilda; Solaro, Giuseppe; Greco, Filippo; Pepe, Antonio; Napoli, Rosalba; Pepe, Susi; Casu, Francesco; Sansosti, Eugenio

    2013-01-01

    Long-term and high temporal resolution gravity and deformation data move us toward a better understanding of the behavior of Mt Etna during the June 1995 – December 2011 period in which the volcano exhibited magma charging phases, flank eruptions and summit crater activity. Monthly repeated gravity measurements were coupled with deformation time series using the Differential Synthetic Aperture Radar Interferometry (DInSAR) technique on two sequences of interferograms from ERS/ENVISAT and COSMO-SkyMed satellites. Combining spatiotemporal gravity and DInSAR observations provides the signature of three underlying processes at Etna: (i) magma accumulation in intermediate storage zones, (ii) magmatic intrusions at shallow depth in the South Rift area, and (iii) the seaward sliding of the volcano's eastern flank. Here we demonstrate the strength of the complementary gravity and DInSAR analysis in discerning among different processes and, thus, in detecting deep magma uprising in months to years before the onset of a new Etna eruption. PMID:24169569

  15. Structural basis for the blockade of MATE multidrug efflux pumps

    DOE PAGES

    Radchenko, Martha; Symersky, Jindrich; Nie, Rongxin; Lu, Min

    2015-08-06

    Multidrug and toxic compound extrusion (MATE) transporters underpin multidrug resistance by using the H+ or Na+ electrochemical gradient to extrude different drugs across cell membranes. MATE transporters can be further parsed into the DinF, NorM and eukaryotic subfamilies based on their amino-acid sequence similarity. Here we report the 3.0 Å resolution X-ray structures of a protonation-mimetic mutant of an H+-coupled DinF transporter, as well as of an H+-coupled DinF and a Na+-coupled NorM transporters in complexes with verapamil, a small-molecule pharmaceutical that inhibits MATE-mediated multidrug extrusion. Combining structure-inspired mutational and functional studies, we confirm the biological relevance of our crystalmore » structures, reveal the mechanistic differences among MATE transporters, and suggest how verapamil inhibits MATE-mediated multidrug efflux. Our findings offer insights into how MATE transporters extrude chemically and structurally dissimilar drugs and could inform the design of new strategies for tackling multidrug resistance.« less

  16. Structural basis for the blockade of MATE multidrug efflux pumps

    SciTech Connect

    Radchenko, Martha; Symersky, Jindrich; Nie, Rongxin; Lu, Min

    2015-08-06

    Multidrug and toxic compound extrusion (MATE) transporters underpin multidrug resistance by using the H+ or Na+ electrochemical gradient to extrude different drugs across cell membranes. MATE transporters can be further parsed into the DinF, NorM and eukaryotic subfamilies based on their amino-acid sequence similarity. Here we report the 3.0 Å resolution X-ray structures of a protonation-mimetic mutant of an H+-coupled DinF transporter, as well as of an H+-coupled DinF and a Na+-coupled NorM transporters in complexes with verapamil, a small-molecule pharmaceutical that inhibits MATE-mediated multidrug extrusion. Combining structure-inspired mutational and functional studies, we confirm the biological relevance of our crystal structures, reveal the mechanistic differences among MATE transporters, and suggest how verapamil inhibits MATE-mediated multidrug efflux. Our findings offer insights into how MATE transporters extrude chemically and structurally dissimilar drugs and could inform the design of new strategies for tackling multidrug resistance.

  17. Transformation of irregular shaped silver nanostructures into nanoparticles by under water pulsed laser melting.

    PubMed

    Yadavali, S; Sandireddy, V P; Kalyanaraman, R

    2016-05-13

    The ability to easily manufacture nanostructures with a desirable attribute, such as well-defined size and shape, especially from any given initial shapes or sizes of the material, will be helpful towards accelerating the use of nanomaterials in various applications. In this work we report the transformation of discontinuous irregular nanostructures (DIN) of silver metal by rapid heating under a bulk fluid layer. Ag films were changed into DIN by dewetting in air and subsequently heated by nanosecond laser pulses under water. Our findings show that the DIN first ripens into elongated structures and then breaks up into nanoparticles. From the dependence of this behavior on laser fluence we found that under water irradiation reduced the rate of ripening and also decreased the characteristic break-up length scale of the elongated structures. This latter result was qualitatively interpreted as arising from a Rayleigh-Plateau instability modified to yield significantly smaller length scales than the classical process due to pressure gradients arising from the rapid evaporation of water during laser melting. These results demonstrate that it is possible to fabricate a dense collection of monomodally sized Ag nanoparticles with significantly enhanced plasmonic quality starting from the irregular shaped materials. This can be beneficial towards transforming discontinuous Ag films into nanostructures with useful plasmonic properties, that are relevant for biosensing applications. PMID:27041091

  18. POTENTIAL IMPACT OF TANK F FLUSH SOLUTION ON H-CANYON EVAPORATOR OPERATION

    SciTech Connect

    Kyser, E.; Fondeur, F.; Fink, S.

    2010-09-13

    Previous chemical analysis of a sample from the liquid heel found in Tank F of the High Activity Drain (HAD) system in F/H laboratory revealed the presence of n-paraffin, tributyl phosphate (TBP), Modifier from the Modular Caustic-Side Solvent Extraction Unit (MCU) process and a vinyl ester resin that is very similar to the protective lining on Tank F. Subsequent analyses detected the presence of a small amount of diisopropylnaphthalene (DIN) (major component of Ultima Gold{trademark} AB liquid scintillation cocktail). Indications are that both vinyl ester resin and DIN are present in small amounts in the flush solution. The flush solution currently in the LR-56S trailer likely has an emulsion which is believed to contain a mixture of the reported organic species dominated by TBP. An acid treatment similar to that proposed to clear the HAD tank heel in F/H laboratory was found to allow separation of an organic phase from the cloudy sample tested by SRNL. Mixing of that clear sample did re-introduce some cloudiness that did not immediately clear but that cloudiness is attributed to the DIN in the matrix. An organic phase does quickly separate from the cloudy matrix allowing separation by a box decanter in H-Canyon prior to transfer to the evaporator feed tank. This separation should proceed normally as long as the emulsion is broken-up by acidification.

  19. FOREWORD: VI Workshop in Electron Volt Neutron Spectroscopy: Frontiers and Horizons

    NASA Astrophysics Data System (ADS)

    Seel, A. G.; Senesi, R.; Fernandez-Alonso, F.

    2014-12-01

    January 2014 saw the congregation in Abingdon (UK) of scientists from across the world, to discuss the current state and future of spectroscopy using epithermal neutrons. This meeting was the sixth in a series of workshops held in collaboration between the Science and Technology Facilities Council (UK) and the Consiglio Nazionale delle Ricerche (Italy), aimed at bringing together researchers with an interest in the use of electron-volt neutrons in spectroscopic studies [1]. This technique is termed Deep Inelastic Neutron Scattering (DINS), and also Neutron Compton Scattering (NCS) in reference to the analogy with Compton scattering of X-rays from electrons. In particular, this meeting centred jointly around experimentalists and theoreticians, formulating animated discussions as to the current overview of DINS and future horizons facing the field. The use of electron Volt neutrons for spectroscopic measurements dates back to the advent of proton-driven spallation neutron sources in the 1970s and 1980s. Following an initial scientific meeting in Los Alamos (USA) [2], the first two meetings in this series were held in Abingdon (UK) in 1995 and 1998, with subsequent meetings held in Santa Fe (USA) in 2005 [3], Oak Ridge National Laboratory (USA) in 2006 [4], and Rome, Italy; in 2010 [5]. The flagship instrument serving a continual user-programme for DINS measurements, and the main focus of this meeting, has been the VESUVIO spectrometer at ISIS [6, 7]. Subsequent instruments like SEQUOIA in the USA [8, 9] and a newer spectrometer in the Bariloche LINAC in Argentina [10, 11] have also been commissioned and began serving a growing user community. The availability of DINS measurements has extended the range of possible spectroscopic techniques that utilise neutrons into the kinematic region of high energy and momentum transfers, shown schematically in Figure 1. Spectroscopic instrument suites such as that of ISIS are thus able to probe processes on timescales across nine

  20. Transformation of irregular shaped silver nanostructures into nanoparticles by under water pulsed laser melting.

    PubMed

    Yadavali, S; Sandireddy, V P; Kalyanaraman, R

    2016-05-13

    The ability to easily manufacture nanostructures with a desirable attribute, such as well-defined size and shape, especially from any given initial shapes or sizes of the material, will be helpful towards accelerating the use of nanomaterials in various applications. In this work we report the transformation of discontinuous irregular nanostructures (DIN) of silver metal by rapid heating under a bulk fluid layer. Ag films were changed into DIN by dewetting in air and subsequently heated by nanosecond laser pulses under water. Our findings show that the DIN first ripens into elongated structures and then breaks up into nanoparticles. From the dependence of this behavior on laser fluence we found that under water irradiation reduced the rate of ripening and also decreased the characteristic break-up length scale of the elongated structures. This latter result was qualitatively interpreted as arising from a Rayleigh-Plateau instability modified to yield significantly smaller length scales than the classical process due to pressure gradients arising from the rapid evaporation of water during laser melting. These results demonstrate that it is possible to fabricate a dense collection of monomodally sized Ag nanoparticles with significantly enhanced plasmonic quality starting from the irregular shaped materials. This can be beneficial towards transforming discontinuous Ag films into nanostructures with useful plasmonic properties, that are relevant for biosensing applications.

  1. Human polymerase kappa uses a template-slippage deletion mechanism, but can realign the slipped strands to favour base substitution mutations over deletions.

    PubMed

    Mukherjee, Purba; Lahiri, Indrajit; Pata, Janice D

    2013-05-01

    Polymerases belonging to the DinB class of the Y-family translesion synthesis DNA polymerases have a preference for accurately and efficiently bypassing damaged guanosines. These DinB polymerases also generate single-base (-1) deletions at high frequencies with most occurring on repetitive 'deletion hotspot' sequences. Human DNA polymerase kappa (hPolκ), the eukaryotic DinB homologue, displays an unusual efficiency for to extend from mispaired primer termini, either by extending directly from the mispair or by primer-template misalignment. This latter property explains how hPolκ creates single-base deletions in non-repetitive sequences, but does not address how deletions occur in repetitive deletion hotspots. Here, we show that hPolκ uses a classical Streisinger template-slippage mechanism to generate -1 deletions in repetitive sequences, as do the bacterial and archaeal homologues. After the first nucleotide is added by template slippage, however, hPolκ can efficiently realign the primer-template duplex before continuing DNA synthesis. Strand realignment results in a base-substitution mutation, minimizing generation of more deleterious frameshift mutations. On non-repetitive sequences, we find that nucleotide misincorporation is slower if the incoming nucleotide can correctly basepair with the nucleotide immediately 5' to the templating base, thereby competing against the mispairing with the templating base. PMID:23558743

  2. Structural basis for the blockade of MATE multidrug efflux pumps

    NASA Astrophysics Data System (ADS)

    Radchenko, Martha; Symersky, Jindrich; Nie, Rongxin; Lu, Min

    2015-08-01

    Multidrug and toxic compound extrusion (MATE) transporters underpin multidrug resistance by using the H+ or Na+ electrochemical gradient to extrude different drugs across cell membranes. MATE transporters can be further parsed into the DinF, NorM and eukaryotic subfamilies based on their amino-acid sequence similarity. Here we report the 3.0 Å resolution X-ray structures of a protonation-mimetic mutant of an H+-coupled DinF transporter, as well as of an H+-coupled DinF and a Na+-coupled NorM transporters in complexes with verapamil, a small-molecule pharmaceutical that inhibits MATE-mediated multidrug extrusion. Combining structure-inspired mutational and functional studies, we confirm the biological relevance of our crystal structures, reveal the mechanistic differences among MATE transporters, and suggest how verapamil inhibits MATE-mediated multidrug efflux. Our findings offer insights into how MATE transporters extrude chemically and structurally dissimilar drugs and could inform the design of new strategies for tackling multidrug resistance.

  3. Linking groundwater-borne nutrients and dinoflagellate red-tide outbreaks in the southern sea of Korea using a Ra tracer

    NASA Astrophysics Data System (ADS)

    Lee, Yong-Woo; Kim, Guebuem

    2007-01-01

    We have measured nutrients, photosynthetic pigments, and two radium isotopes ( 223Ra and 224Ra) in coastal groundwater and seawater during the summer of 2002 and 2003 in the southern sea of Korea, where harmful dinoflagellate blooms (hereafter red tides) have been occurring every year since 1982. In this region, the amount of submarine groundwater discharge (SGD) is known to be two orders of magnitude higher than the surface runoff. Good correlations of dissolved inorganic nitrogen (DIN) and silicate (DSi) with groundwater-borne 224Ra (half life = 3.66 days) in the initial red-tide waters of 2002 confirm that the source of these nutrients is SGD. In addition, the DIN/DIP ratios in 2002 and total dissolved nitrogen/phosphorus (TDN/TDP) ratios in 2003 in red-tide waters ranged from 30 to 300, similar to those observed in groundwater. The spatial and temporal variations of nutrients and photosynthetic pigments showed that red tides broke out when DIN or DIP (dissolved inorganic phosphorus) were almost depleted, limiting the growth of diatoms. Thus, our observations reveal that the emergence of harmful dinoflagellate red tides might be facilitated by inter-specific competition of phytoplankton species when inorganic nutrients are limited and dissolved organic nutrients, converted from groundwater-borne nutrients, are sufficient.

  4. Transformation of irregular shaped silver nanostructures into nanoparticles by under water pulsed laser melting

    NASA Astrophysics Data System (ADS)

    Yadavali, S.; Sandireddy, V. P.; Kalyanaraman, R.

    2016-05-01

    The ability to easily manufacture nanostructures with a desirable attribute, such as well-defined size and shape, especially from any given initial shapes or sizes of the material, will be helpful towards accelerating the use of nanomaterials in various applications. In this work we report the transformation of discontinuous irregular nanostructures (DIN) of silver metal by rapid heating under a bulk fluid layer. Ag films were changed into DIN by dewetting in air and subsequently heated by nanosecond laser pulses under water. Our findings show that the DIN first ripens into elongated structures and then breaks up into nanoparticles. From the dependence of this behavior on laser fluence we found that under water irradiation reduced the rate of ripening and also decreased the characteristic break-up length scale of the elongated structures. This latter result was qualitatively interpreted as arising from a Rayleigh–Plateau instability modified to yield significantly smaller length scales than the classical process due to pressure gradients arising from the rapid evaporation of water during laser melting. These results demonstrate that it is possible to fabricate a dense collection of monomodally sized Ag nanoparticles with significantly enhanced plasmonic quality starting from the irregular shaped materials. This can be beneficial towards transforming discontinuous Ag films into nanostructures with useful plasmonic properties, that are relevant for biosensing applications.

  5. Multislice simulation of transmission electron microscopy imaging of helium bubbles in Fe

    SciTech Connect

    Yao, Bo; Edwards, Danny J.; Kurtz, Richard J.; Odette, George R.; Yamamoto, Takuya

    2012-10-04

    Formation of nanoscale helium (He) bubbles in reduced activation ferritic/martensitic steels may lead to degradation of mechanical properties of materials. Transmission electron microscopy (TEM) has been commonly used to image the Fresnel contrast of He bubbles using a defocus of 0.5 µm ~ 1 µm. This paper presents our study of multislice simulation of the size correlation between imaged Fresnel rings and the actual He bubbles. It was found that for bubbles equal to or larger than 3 nm in diameter, the imaged bubble size, represented by its inner diameter of the first dark Fresnel ring (Din) in under-focused imaging conditions, increases with increasing electron-beam incoherency, but decreases with increasing defocus. The electron-beam accelerating voltage, bubble size, bubble position, and TEM sample thickness were found to have no significant influence on the deviation of Din from the actual bubble size (D0). For bubbles equal to or smaller than 2 nm, however, Din/Do increases dramatically with increasing defocus when it is above a threshold defocus. It was also suggested by this study that He bubbles can be differentiated from argon (Ar) bubbles by contrast differences.

  6. Net Subterranean Estuarine Export Fluxes of Dissolved Inorganic C, N, P, Si, and Total Alkalinity into the Jiulong River Estuary, China

    NASA Astrophysics Data System (ADS)

    Wang, G.; Wang, Z.; Zhai, W. D.; Moore, W. S.; Li, Q.; Yan, X.; Qi, D.; Jiang, Y.

    2014-12-01

    To evaluate geochemical impacts of the subterranean estuary (STE) on the Jiulong River estuary, China, we estimated seasonal fluxes of subterranean water discharge into the estuary based on the mass balance of radium isotopes and net subterranean export fluxes of dissolved inorganic C (DIC), N (DIN), Si (DSi), soluble reactive phosphorus (SRP), and total alkalinity (TA). Based on 226Ra data, the subterranean discharge (in 107 m3 d-1) was estimated to be 0.24~0.51 in the spring, 0.56~1.16 in the summer, 0.38~0.79 in the fall, and 0.22~0.45 in the winter. This was equivalent to 6-16% of the concomitant river discharge. The net spatially integrated material fluxes from the STE into the estuary were equivalent up to 51-89% of the concomitant riverine fluxes for DIC and TA, around 10-25% for DSi and DIN, and negligible for SRP. Paradoxically, the mixing lines along the salinity gradient revealed no apparent additions of these species. These additions are not revealed because the STE is a relatively small spatially-averaged source that spreads throughout the estuary in contrast to the major point sources of the river and the ocean for the estuary. Thus, despite apparent conservative mixing of DIC, DIN, and DSi, subterranean exports of these species into estuaries must be taken into account in evaluating geochemical impacts of estuarine exports on shelf waters.

  7. Unraveling the nitrogen isotopic signature of symbiotic corals

    NASA Astrophysics Data System (ADS)

    Devlin, Q.; Swart, P. K.; Altabet, M. A.

    2013-12-01

    Coral reefs thrive in shallow, tropical, low nutrient waters. Nutrient inputs to a reef environment are often interpreted by measuring the nitrogen isotopic composition of reef organisms. The δ15N signature of scleractinian corals has been historically measured to assess the presence of anthropogenic influences such as sewage and fertilizer runoff. The majority of reef building corals form a symbiotic partnership with the dinoflagellate algae, Symbiodinium microadriaticum. The δ15N signature of symbiotic corals is complex as it is not only dependent on nitrogen acquisition by the coral, but also by the algal symbionts that reside within the gastrodermal tissue layer. The relationship between the δ15N of dissolved inorganic nitrogen (DIN) and the δ15N of coral tissue has not been established. The aim of this study is to identify considerations necessary when interpreting nitrogen sources based on δ15N of coral tissue. Incubations were carried out in order to measure isotopic fractionation associated with nitrate and ammonium incorporation by the Pacific branching coral, Pocillopora damicornis. We investigated the dependence of nitrogen isotope fractionation on species of DIN (nitrate or ammonium), concentration of DIN (range: 1-50 μM N), genetic diversity of algal symbionts (clade C or clade D) and light levels.

  8. [Seasonal variation and spatial distribution of nutrients and their relationships with harmful algal blooms in coastal area of the East China Sea].

    PubMed

    Zhang, Chuan-Song; Wang, Xiu-Lin; Shi, Xiao-Yong; Tang, Hong-Jie; Han, Xiu-Rong; Xin, Yu

    2007-11-01

    Based on the data from four cruises that carried out in the Changjiang River estuary and its adjacent areas from 2002-04 to 2003-02, the seasonal variation and spatial distribution of nutrients were analyzed, and the relationship between nutrients condition and the harmful algal blooms (HABs) was also discussed. Results showed that the annual average concentration of nutrient was (17.93 +/- 2.46) micromol x L(-1) for DIN, (0.59 +/- 0.11) micromol x L(-1) for PO4(3-) -P, (15.34 +/- 3.23) micromol x L(-1) for SiO3(2-) -Si, and the study area was in the state of eutrophication. The average concentration of nutrient showed a remarkable seasonal fluctuation with the higher value in autumn and winter and lower value in spring and summer. The spatial distribution of the nutrients was typically such that the concentrations of DIN, PO4(3-) -P and SiO3(2-) -Si decreased from inshore to offshore area, and the contours generally decreased rapidly in down-coast directions. DIN and SiO3(2-) -Si of the study area were largely contributed by Changjiang River diluted water and other terrigenous inputs, while PO4(3-) -P mainly by Changjiang River diluted water and the Taiwan Warm Current. The following HABs showed that its occurrences were usually laid in the areas with higher nutrients and lower total suspended particles (TSP).

  9. Complementary Use of Information from Space-Based Dinsar and Field Measuring Systems for Operational Monitoring Purposes in Open Pit Iron Mines of Carajas Mining Complex (brazilian Amazon Region)

    NASA Astrophysics Data System (ADS)

    Paradella, W. R.; Mura, J. C.; Gama, F. F.; Santos, A. R.; Silva, G. G.; Galo, M.; Camargo, P. O.; Silva, A. Q.

    2015-04-01

    Now spanning five simultaneous open-pit operations with exploration carried out through open pit benching, Carajas complex encompasses the world's largest iron reserves. Open pit mining operations in the area can lead to slope instabilities with risks to personnel, equipment and production due to intense excavations in rock products of low geomechanical quality, blasting practices and heavy precipitation. Thus, an effective prediction and management of surface deformations should be a key concern for the mining operations. The ground displacement monitoring techniques in Carajas include surface measurement techniques at discrete points (total station/reflective prisms) and over area using SSR (Slope Stability Radar, a ground based radar). On the other hand, DInSAR techniques are receiving relevance in the mining industry for reasons such a synoptic and continuous coverage without the need for ground instrumentation and a point-to-point good accuracy of measuring displacements (millimeter to centimeter scale) over a dense grid. Using a stack of 33 StripMap TerraSAR-X images acquired over Carajas covering the time span from March 2012 to April 2013, a monitoring approach is discussed based on the complementary use of information provided by DInSAR (DInSAR Time-Series and Persistent Scatterer Interferometry) and surface measuring techniques (total station/prisms, ground-based radar).

  10. Atmospheric input of inorganic nitrogen and phosphorus to the Ligurian Sea: Data from the Cap Ferrat coastal time-series station

    NASA Astrophysics Data System (ADS)

    de Fommervault, Orens Pasqueron; Migon, Christophe; Dufour, Aurélie; D'Ortenzio, Fabrizio; Kessouri, Fayçal; Raimbault, Patrick; Garcia, Nicole; Lagadec, Véronique

    2015-12-01

    Atmospheric fluxes of bio-available inorganic nitrogen (DIN, i.e. nitrate+ammonium) and phosphorus (DIP, i.e. phosphate) were measured in 2010, 2011 and 2013 at the sampling station of Cap Ferrat (Ligurian Sea). Wet and dry fluxes of DIN, averaged over three years, were 35 and 19 mmol m-2 yr-1, respectively. Most of the nitrate was deposited under dry form, whilst ammonia was twice more found in wet deposition. Wet and dry fluxes of DIP, averaged over three years, were 0.11 and 0.64 mmol m-2 yr-1, respectively. Atmospheric fluxes of DIN and DIP were compared with other photic zone nutrient input sources, physical and biological, i.e. winter convection, N2 fixation, and upward diffusion. Even if convection is by far the most important nutrient input for surface waters, atmospheric sources may be the second one, supplying more nutrients than diazotrophy and diffusion, particularly in conditions of water column stratification.

  11. Variations in seasonal phytoplankton assemblages as a response to environmental changes in the surface waters of a hypo saline coastal station along the Bhagirathi-Hooghly estuary.

    PubMed

    Choudhury, Avik Kumar; Pal, Ruma

    2011-08-01

    Due to the close proximity of the Bay of Bengal and the freshwater inflow of Bhagirathi-Hooghly, Diamond Harbour appeared as an important coastal station of the Bhagirathi-Hooghly estuary. The spatial and temporal composition and abundance of microphytoplankton species was examined in relation to physical and chemical surface water variables (i.e., salinity, nutrient, and temperature).The primary objective of the study was to observe the variations in phytoplankton species assemblages as a response to environmental variables. Hierarchical cluster analysis and non-metric multidimensional scaling were used to find out distinct seasonal groups based on the composition of phytoplankton. The results indicate that several key environmental factors like temperature, DIN content, and molar ratio of nutrients like DIN-DIP and DIN-DSi influenced seasonal phytoplankton assemblages within the estuary. The distribution of phytoplankton population showed two main groups where the blue-green and green algal populations favored the warmer conditions of summer and monsoon months, whereas the diatom population primarily flourished in the cooler months of autumn and winter.

  12. Increasing nutrient concentrations and the rise and fall of a coastal fishery; a review of data from the Nile Delta, Egypt

    NASA Astrophysics Data System (ADS)

    Oczkowski, Autumn; Nixon, Scott

    2008-04-01

    There is a conceptual basis, and some empirical evidence, that increasing nutrient loads to coastal waterbodies will initially increase ecosystem productivity up to a threshold, beyond which secondary productivity and fishery yields will decline. Here we have compiled data from the Egyptian and international literature for fish landings and inorganic nutrient (nitrogen and phosphorus) data from four large coastal lagoons (63-500 km 2) on Egypt's Nile Delta to provide evidence for the initially positive, but then negative, response of fishery yields to increased nutrient supply across a very wide range of enrichment (up to 1 mM dissolved organic nitrogen, DIN). Taking the data from the four lagoons as an aggregate, fish landings increase with increased nutrients up to a peak in landings at approximately 100 μM DIN, beyond which there was an exponential decline in landings. It appears that pesticide and heavy metal contamination and overfishing played only minor roles in the lowered fishery yield at highest DIN concentrations. We do not have sufficient evidence about the specific mechanisms that led to the decline of the fishery, but suspect that some feature of eutrophication—low oxygen, for example, may have been involved.

  13. Capturing the fingerprint of Etna volcano activity in gravity and satellite radar data.

    PubMed

    Del Negro, Ciro; Currenti, Gilda; Solaro, Giuseppe; Greco, Filippo; Pepe, Antonio; Napoli, Rosalba; Pepe, Susi; Casu, Francesco; Sansosti, Eugenio

    2013-01-01

    Long-term and high temporal resolution gravity and deformation data move us toward a better understanding of the behavior of Mt Etna during the June 1995 - December 2011 period in which the volcano exhibited magma charging phases, flank eruptions and summit crater activity. Monthly repeated gravity measurements were coupled with deformation time series using the Differential Synthetic Aperture Radar Interferometry (DInSAR) technique on two sequences of interferograms from ERS/ENVISAT and COSMO-SkyMed satellites. Combining spatiotemporal gravity and DInSAR observations provides the signature of three underlying processes at Etna: (i) magma accumulation in intermediate storage zones, (ii) magmatic intrusions at shallow depth in the South Rift area, and (iii) the seaward sliding of the volcano's eastern flank. Here we demonstrate the strength of the complementary gravity and DInSAR analysis in discerning among different processes and, thus, in detecting deep magma uprising in months to years before the onset of a new Etna eruption. PMID:24169569

  14. [Distributional characteristics of nutrients in the sea-surface microlayer and subsurface water of the Bohai and Yellow Sea in summer].

    PubMed

    Wang, Wen-Tao; Yang, Gui-Peng; Yu, Juan; Wu, Guan-Wei

    2013-08-01

    The horizontal distributional characteristics of nutrients (DIN, PO4(3-) -P, SiO3(2-) -Si) were studied in the sea-surface microlayer (SML) and subsurface water of the Bohai and Yellow Sea in June 2011, and the vertical distributions of nutrients in the transects of the Yellow Sea Cold Water Mass and the north of the Changjiang River estuary were also investigated. The results showed that the nutrient concentrations in the sea-surface microlayer and subsurface water decreased gradually from inshore to offshore, and higher values were observed in the Changjiang River estuary. A tongue-shaped distribution was observed in the south of the Yellow Sea as a result of the Changjiang diluted water. Stratification occurred in the surface layer and vertical mixing characteristics were observed in the bottom due to the influence of the Yellow Sea Cold Water Mass. In the vertical distributions, higher concentrations of DIN and SiO3(2-) -Si in the north of the Changjiang River estuary occurred in the sea surface compared with the bottom due to the Changjiang River diluted water. The enrichment results of NH(+) -N, NO2(-) -N, NO3(-)-N, PO4(3-) -P, SiO3(2-)-Si and DIN showed that the sea-surface microlayer displayed an apparent enrichment for nutrients except NO3(-) -N, and the mean enrichment factors ranged from 1.37 to 2.21.

  15. Interferometric SAR monitoring of the Vallcebre landslide (Spain) using corner reflectors

    NASA Astrophysics Data System (ADS)

    Crosetto, M.; Gili, J. A.; Monserrat, O.; Cuevas-González, M.; Corominas, J.; Serral, D.

    2013-04-01

    This paper describes the deformation monitoring of the Vallcebre landslide (Eastern Pyrenees, Spain) using the Differential Interferometric Synthetic Aperture Radar (DInSAR) technique and corner reflectors (CRs). The fundamental aspects of this satellite-based deformation monitoring technique are described to provide the key elements needed to fully understand and correctly interpret its results. Several technical and logistic aspects related to the use of CRs are addressed including an analysis of the suitability of DInSAR data to monitor a specific landslide, a discussion on the choice of the type of CRs, suggestions for the installation of CRs and a description of the design of a CR network. This is followed by the description of the DInSAR data analysis procedure required to derive deformation estimates starting from the main observables of the procedure, i.e., the interferometric phases. The main observation equation is analysed, discussing the role of each phase component. A detailed discussion is devoted to the phase unwrapping problem, which has a direct impact on the deformation monitoring capability. Finally, the performance of CRs for monitoring ground displacements has been tested in the Vallcebre landslide (Eastern Pyrenees, Spain). Two different periods, which provide interesting results to monitor over time the kinematics of different parts of the considered landslide unit, are analysed and described.

  16. DNA-damaging agents stimulate gene expression at specific loci in Escherichia coli

    SciTech Connect

    Kenyon, C.J.; Walker, G.C.

    1988-05-01

    Operon fusions in Escherichia coli were obtained that showed increased beta-galactosidase expression in response to treatment with the DNA-damaging agent mitomycin C. These fusions were generated by using the Mud(ApR, lac) vector to insert the lactose structural genes randomly into the bacterial chromosome. Induction of beta-galactosidase in these strains, which carried fusions of lac to these din (damage-inducible) loci, was (i) triggered by UV light as well as by mitomycin C and (ii) abolished by either a recA- or a lexA- mutation. Similar characteristics of induction were observed when the lactose genes were fused to a prophage lambda promoter by using Mud(ApR, lac). These results indicate that E. coli contains a set of genes that, like prophage lambda genes, are expressed in response to DNA-damaging agents and regulated by the recA and lexA gene products. These din genes map at five bacterial loci. One din::Mud(ApR, lac) insertion results in a UV-sensitive phenotype and may be within the uvrA transcriptional unit.

  17. Linking Land-Use to Submarine Groundwater Discharge Nutrient Fluxes on Maui, Hawaii

    NASA Astrophysics Data System (ADS)

    Bishop, J. M.; Glenn, C. R.; Amato, D. W.; Dulaiova, H.

    2014-12-01

    Fertilized agricultural lands, wastewater injection, and areas with high septic system density each have substantial potential for contributing excess nutrients to the coastal waters of islands via submarine groundwater discharge (SGD). We evaluated the coastal impacts of such land-use around the island of Maui using stable isotopes (δ15N of NO3-; δ18O and δ2H of H2O) and nutrient concentrations from wells, springs, beach seeps, SGD, and coastal waters, and coupled these to coastal water SGD and nutrient fluxes using 222Rn mass balance. Flowpaths and recharge elevations for groundwater samples were determined using the δ18OH2O of samples, recharge data, modeled groundwater head, and published local meteoric water lines. Coastal groundwater samples whose flowpaths transect sugarcane plots showed highest dissolved inorganic nitrogen (DIN - NO3- + NO2-) concentrations, ranging from 225 - 450 µM, and the δ15N of those samples was on average 3.3 ± 0.6 ‰ (n = 15), as expected for urea fertilizers applied to commercial sugarcane. Samples whose flowpaths transect large amounts of septic sources showed moderate DIN concentrations (max. 100 µM), but had higher δ15N values (9.7 ± 4.8 ‰, n = 5), reflecting their sewage influence. Due to nitrate reduction during subterranean transit, groundwater and coastal waters proximal to deep, near-coast wastewater injection (Kahului) display the highest average δ15N values encountered (δ15NNO3- 18.8 ± 11.1 ‰, n = 19) and moderate DIN concentrations (max 90 µM). Average SGD nutrient fluxes among the different field sites ranged from 700 - 1,500,000 µmol/d/m of shoreline for DIN and 600 - 22,000 µmol/d/m for orthophosphate. These results indicate that areas with the highest N and P fluxes are areas where coastal groundwater flowpaths transect large tracts of sugarcane production. Although highest SGD rates occur near the Kahului wastewater injection wells (~ 2800 m3/day) the relatively low nutrient concentrations in

  18. Growth of a young pingo in the Canadian Arctic observed by RADARSAT-2 interferometric satellite radar

    NASA Astrophysics Data System (ADS)

    Samsonov, S. V.; Lantz, T. C.; Kokelj, S. V.; Zhang, Y.

    2015-11-01

    Advancements in radar technology are increasing our ability to detect earth surface deformation in permafrost environments. In this paper we use satellite Differential Interferometric Synthetic Aperture Radar (DInSAR) to describe the growth of a previously unreported pingo in the Tuktoyaktuk Coastlands. High-resolution RADARSAT-2 imagery (2011-2014) analyzed with the Multidimensional Small Baseline Subset (MSBAS) DInSAR revealed a maximum 2.7 cm yr-1 of domed uplift located in a drained lake basin. Observed changes in elevation were modeled as a 348 m × 290 m uniformly loaded elliptical plate with clamped edge. Model results suggest that this feature is one of the largest diameter pingos in the region that is presently growing. Analysis of historical aerial photographs showed that ground uplift at this location initiated sometime between 1935 and 1951 following lake drainage. Uplift is largely due to the growth of intrusive ice, because the 9 % expansion of pore water associated with permafrost aggradation into saturated sands is not sufficient to explain the observed short- and long-term deformation rates. The modeled thickness of permafrost using the Northern Ecosystem Soil Temperature (NEST) was consistent with the maximum height of this feature and the 1972-2014 elevation changes estimated from aerial photographs, suggesting that permafrost aggradation is resulting in the freezing a sub-pingo water lens. Seasonal variation in the uplift rate seen in the DInSAR data also matches the modeled seasonal pattern in the deepening rate of freezing front. This study demonstrates that interferometric satellite radar can successfully contribute to understanding the dynamics of terrain uplift in response to permafrost aggradation and ground ice development in remote polar environments, and highlights possible application of detecting deformation of Martian landscapes. However, our DInSAR data did not show clear growth at other smaller pingos in contrast with field studies

  19. Benthic nitrogen cycling traversing the capitalize peruvian oxygen minimum zone

    NASA Astrophysics Data System (ADS)

    Bohlen, L.; Dale, A. W.; Sommer, S.; Mosch, T.; Hensen, C.; Noffke, A.; Scholz, F.; Wallmann, K.

    2011-10-01

    Benthic nitrogen (N) cycling was investigated at six stations along a transect traversing the Peruvian oxygen minimum zone (OMZ) at 11°S. An extensive dataset including porewater concentration profiles and in situ benthic fluxes of nitrate (NO 3-), nitrite (NO 2-) and ammonium (NH 4+) was used to constrain a 1-D reaction-transport model designed to simulate and interpret the measured data at each station. Simulated rates of nitrification, denitrification, anammox and dissimilatory nitrate reduction to ammonium (DNRA) by filamentous large sulfur bacteria (e.g. Beggiatoa and Thioploca) were highly variable throughout the OMZ yet clear trends were discernible. On the shelf and upper slope (80-260 m water depth) where extensive areas of bacterial mats were present, DNRA dominated total N turnover (⩽2.9 mmol N m -2 d -1) and accounted for ⩾65% of NO 3- + NO 2- uptake by the sediments from the bottom water. Nonetheless, these sediments did not represent a major sink for dissolved inorganic nitrogen (DIN = NO 3- + NO 2- + NH 4+) since DNRA reduces NO 3- and, potentially NO 2-, to NH 4+. Consequently, the shelf and upper slope sediments were recycling sites for DIN due to relatively low rates of denitrification and high rates of ammonium release from DNRA and ammonification of organic matter. This finding contrasts with the current opinion that sediments underlying OMZs are a strong sink for DIN. Only at greater water depths (300-1000 m) did the sediments become a net sink for DIN. Here, denitrification was the major process (⩽2 mmol N m -2 d -1) and removed 55-73% of NO 3- and NO 2- taken up by the sediments, with DNRA and anammox accounting for the remaining fraction. Anammox was of minor importance on the shelf and upper slope yet contributed up to 62% to total N 2 production at the 1000 m station. The results indicate that the partitioning of oxidized N (NO 3-, NO 2-) into DNRA or denitrification is a key factor determining the role of marine sediments as DIN

  20. Fate of Upstream Anthropogenic Nitrogen Inputs in a Tropical Catchment, Athi-Galana-Sabaki River, Kenya.

    NASA Astrophysics Data System (ADS)

    Marwick, Trent R.

    2013-04-01

    As part of a broader study on the riverine biogeochemistry in the Athi-Galana-Sabaki (A-G-S) River basin (Kenya), we present data collected during three climatic seasons to constrain the sources, transformations and transit of multiple N species as they flow through the A-G-S basin (~47,000 km2), stretching from downstream of heavily polluted Nairobi and surrounds to the outlet at the Indian Ocean. Total dissolved inorganic nitrogen (DIN) concentrations entering the study area were highest during the dry season (1195 µmol/L), almost completely in the form of ammonium (99.8%), whilst total DIN was an order of magnitude lower during the short and long rain seasons (212 and 193 µmol/L, respectively). Nitrate was the dominant form of DIN entering the study area during the short and long rain seasons (97.9% and 85.6% of total DIN respectively), with the increased flow conditions resulting in minimal instream N-cycling prior to discharge to the ocean. Conversely, longer water residence time and intense cycling and removal of N in the upper- to mid-catchment during the dry season creates two polarities comparative to wet season conditions, where (1) significantly less DIN is exported to the ocean during the dry season, and (2) dry season particulate N export is significantly enriched in δ15N, strongly reflecting the dominance of organic wastes as the source of riverine nitrogen. The rapid removal of ammonium in the upper study area during the dry season was followed by a quantitatively similar production of nitrate and nitrous oxide downstream, pointing towards strong nitrification over this reach during the dry season. The nitrous oxide was rapidly degassed downstream, while the elevated nitrate concentrations steadily decreased to levels observed elsewhere in African river networks. Low pelagic primary production rates over the same reach suggest benthic denitrification was the dominant process controlling the removal of these nitrates, although large cyanobacterial

  1. Measuring ecosystem nitrogen status: a comparison of proxies

    NASA Astrophysics Data System (ADS)

    Almaraz, M.; Porder, S.

    2013-12-01

    Nitrogen (N) limitation to primary production is widespread in both terrestrial and aquatic systems, and variation in N availability drives differences in ecosystem properties across space and time. Instantaneous measurements of N availability in soil are common, but it is difficult to assess whether proxies commonly used to infer long-term N status over space or time adequately integrate these short-term measurements. Nevertheless, these longer temporal, and larger spatial, scales are relevant to many ecosystem properties and responses to global change. Here we assess how well several proxies that purportedly reflect time or space-integrated N availability correlate with each other when they are measured in the same place. We surveyed the literature and contacted individual investigators to gather data from intact forest and grassland sites where several proxies of long-term N availability had been measured. We focused on the most commonly-used proxies for N status: foliar and soil δ15N, net N mineralization, net nitrification, the ratio of dissolved inorganic to organic N forms in soil solution below the rooting zone (DIN:DON), and the DIN:DON in streams. We found that soil δ15N is positively correlated with foliar δ15N (r=0.63, p=0.0008, n=25), but is negatively correlated with net N mineralization (r=0.73, p=0.0101, n=11). There was not a significant correlation between soil δ15N and nitrification (r=0.08, p=0.8107, n=11), soil solution DIN:DON (r=0.28, p=0.1217, n=32), or stream DIN:DON (r=0.04, p=0.9104, n=9). Foliar δ15N is positively correlated with nitrification (r=0.70, p=0.0359, n=9), but there was not a significant correlation between foliar δ15N and net N mineralization (r=0.63, p=0.0666, n=9), or soil solution DIN:DON (r=0.10, p=0.6290, n=24). We found no significant correlation between net N mineralization and net nitrification (r=0.33, p=0.3232, n=11), nor do we see a significant correlation between soil solution and stream DIN:DON (r=0.58, p

  2. Landscape controls on dissolved nutrients, organic matter and major ions in a suburbanizing watershed

    NASA Astrophysics Data System (ADS)

    Daley, M. L.; McDowell, W. H.

    2010-12-01

    Understanding the relative importance of anthropogenic and natural landscape features that drive spatial variability in water quality is a central challenge in studying the biogeochemistry of heterogeneous landscapes. We quantified the average annual flux and concentration of dissolved inorganic nitrogen (DIN), dissolved organic nitrogen (DON), dissolved organic carbon (DOC), phosphate-P (PO4-P), sodium (Na+) and chloride (Cl-) at ~40 stream sites in three major (51 to 903 km2) NH basins. We used GIS to quantify anthropogenic (e.g. human population density, % impervious surface cover and % agriculture) and natural (e.g. % forest, % wetlands and soil C:N) landscape features for each sub-basin and then employed multiple-regression analysis to relate water quality parameters to landscape characteristics. Anthropogenic features were strong predictors of DIN flux and Na+ and Cl- concentrations, whereas wetland cover (a natural feature) was a significant, but weak predictor of DOC (r2=0.26, p<0.01) and DON (r2 = 0.14, p<0.05) flux. Anthropogenic features could not explain a significant amount of variance in DON or DOC flux. Mean PO4-P concentrations were surprisingly low (<0.015 mg P/L) when compared to the larger range in mean DIN concentrations (0.03 to 0.96 mg/L) and consequently no landscape characteristics could explain a significant amount of spatial variability in PO4-P flux or concentration. Human population density was the single best predictor of DIN flux (r2=0.76, p<0.01), and together with % impervious surface and % agriculture explained 86% (p<0.01) of the total variance. Among all sites, % road pavement was a strong predictor of stream Na+ and Cl- concentrations (r2 = 0.75 to 0.78, p<0.01) and % impervious surface was a stronger predictor (r2 = 0.86 to 0.92, p<0.01) among a subset of sites. Our results suggest that DIN and DON result from different sources in the landscape and although sources of DON and DOC are similar, DON and DOC concentrations respond

  3. Landslide Kinematical Analysis through Inverse Numerical Modelling and Differential SAR Interferometry

    NASA Astrophysics Data System (ADS)

    Castaldo, R.; Tizzani, P.; Lollino, P.; Calò, F.; Ardizzone, F.; Lanari, R.; Guzzetti, F.; Manunta, M.

    2015-11-01

    The aim of this paper is to propose a methodology to perform inverse numerical modelling of slow landslides that combines the potentialities of both numerical approaches and well-known remote-sensing satellite techniques. In particular, through an optimization procedure based on a genetic algorithm, we minimize, with respect to a proper penalty function, the difference between the modelled displacement field and differential synthetic aperture radar interferometry (DInSAR) deformation time series. The proposed methodology allows us to automatically search for the physical parameters that characterize the landslide behaviour. To validate the presented approach, we focus our analysis on the slow Ivancich landslide (Assisi, central Italy). The kinematical evolution of the unstable slope is investigated via long-term DInSAR analysis, by exploiting about 20 years of ERS-1/2 and ENVISAT satellite acquisitions. The landslide is driven by the presence of a shear band, whose behaviour is simulated through a two-dimensional time-dependent finite element model, in two different physical scenarios, i.e. Newtonian viscous flow and a deviatoric creep model. Comparison between the model results and DInSAR measurements reveals that the deviatoric creep model is more suitable to describe the kinematical evolution of the landslide. This finding is also confirmed by comparing the model results with the available independent inclinometer measurements. Our analysis emphasizes that integration of different data, within inverse numerical models, allows deep investigation of the kinematical behaviour of slow active landslides and discrimination of the driving forces that govern their deformation processes.

  4. Heterotrophic plate count and consumer's health under special consideration of water softeners.

    PubMed

    Hambsch, Beate; Sacré, Clara; Wagner, Ivo

    2004-05-01

    The phenomenon of bacterial growth in water softeners is well known since years. To upgrade the hygienic safety of water softeners, the German DIN Standard 19636 was developed, to assure that the distribution system could not be contaminated by these devices and that the drinking water to be used in the household still meets the microbiological standards according to the German drinking water guidelines, i.e. among others heterotrophic plate count (HPC) below 100 CFU/ml. Moreover, the standard for the water softeners includes a test for contamination with Pseudomonas aeruginosa which has to be disinfected during the regeneration phase. This is possible by sanitizing the resin bed during regeneration by producing chlorine. The results of the last 10 years of tests of water softeners according to DIN 19636 showed that it is possible to produce water softeners that comply with that standard. Approximately 60% of the tested models were accepted. P. aeruginosa is used as an indicator for potentially pathogenic bacteria being able to grow also in low nutrient conditions which normally prevail in drinking water. Like other heterotrophs, the numbers of P. aeruginosa increase rapidly as stagnation occurs. Normally P. aeruginosa is not present in the distributed drinking water. However, under certain conditions, P. aeruginosa can be introduced into the drinking water distribution system, for instance, during construction work. The occurrence of P. aeruginosa is shown in different cases in treatment plants, public drinking water systems and in-house installations. The compliance with DIN 19636 provides assurance that a water softener will not be a constant source of contamination, even if it is once inoculated with a potentially pathogenic bacterium like P. aeruginosa.

  5. The import and export of organic nitrogen species at a Scottish ombrotrophic peatland

    NASA Astrophysics Data System (ADS)

    McKenzie, R. M.; Özel, M. Z.; Cape, J. N.; Drewer, J.; Dinsmore, K. J.; Nemitz, E.; Hamilton, J. F.; Sutton, M. A.; Gallagher, M. W.; Skiba, U.

    2015-01-01

    Dissolved organic nitrogen (DON) can contribute significantly to the overall nitrogen budget, but is not routinely measured in precipitation or stream water. In order to investigate the contribution of DON to deposition and export of N, precipitation, stream and soil water samples were collected from an ombrotrophic peatland and analysed for DON Over a two year period. In wet only deposition DON contributed up to 10% of the total dissolved nitrogen (TDN), 99% in soil water, and 75% in stream water. No correlations were observed between DIN and DON in precipitation stream water or soil water. DIN is an important source of nutrients and in ombrotrophic peatlands, is only deposited via precipitation. Too much nitrogen to a sensitive ecosystem can result in problems with the way in which it is processed, such as an increase in the export of N via nearby water bodies. It is therefore important to monitor N deposition and export. Precipitation DIN showed a loose seasonal pattern, with peak concentrations occurring between January and June, while DON concentrations tended to be lower in the winter months. Stream water DON and NH4+ showed no obvious seasonal pattern but NO3- showed larger concentrations in cooler months and the smallest during warmer months, with the exception of June and July 2010, when concentrations were high. Precipitation and stream DON was qualitatively analysed using GC × GC-NCD. Ten unique compounds were detected, of which only five could be identified: pyrrole, benzonitrile, dodecylamine, N-nitrosodipropylamine and decylamine. Five compounds were present in both precipitation and stream samples: pyrrole, benzonitrile and three unidentified compounds. A more detailed DON speciation may be used to identify sources and pathways of DON.

  6. Distributions of inorganic nutrients in the bohai sea of china

    NASA Astrophysics Data System (ADS)

    Zhengyan, Li; Jie, Bai; Jinhui, Shi; Huiwang, Gao

    2003-04-01

    To study the contents and distribution of inorganic nutrients in the Bohai Sea of China, two cruise surveys were undertaken in August (summer) 2000 and January (winter) 2001, respectively. A total of 595 water samples were collected from 91 stations and five nutrients, i.e., nitrate, nitrite, ammonia, phosphate and silicate, were analyzed for each sample. The results show that the average concentration of dissolved inorganic nitrogen (DIN) in the Bohai Sea in winter (6.529 μmol L-1) is significantly higher than that in summer (3.717 μmol L-1). The phosphorus concentration in winter (0.660 μmol L-1) is also significantly higher than that in summer (0.329 μmol L-1). Mean silicate concentration in winter (7.858 μmol L-1) is, however, not significantly different from that in summer (7.200 μmol L-1). Nutrients also vary considerably in different areas in Bohai Sea. DIN concentration in the Laizhou Bay (4.444 μmol L-1), for example, is significantly higher than those in the Bohai Bay (2.270 μmol L-1) and Bohai Strait (2.431 μmol L-1), which is caused by the discharge of large amounts of nitrogen into Laizhou Bay via Yellow River. The nutrients show different vertical distribution patterns. In summer, nutrients in bottom layer are generally richer than those in surface and middle layers. In winter, however, nutrients are not significantly different in different layers. Compared with historic data, DIN contents have increased continually since the early 1980 s. Based on atomic ratios of different nutrients, nitrogen is still the limiting factor for algal growth in the Bohai Sea.

  7. Purification and Characterization of the Staphylococcus aureus Bacillithiol Transferase BstA

    PubMed Central

    Perera, Varahenage R.; Newton, Gerald L.; Parnell, Jonathan M.; Komives, Elizabeth A.; Pogliano, Kit

    2016-01-01

    Background Gram-positive bacteria in the phylum Firmicutes synthesize the low molecular weight thiol bacillithiol rather than glutathione or mycothiol. The bacillithiol transferase YfiT from Bacillus subtilis was identified as a new member of the recently discovered DinB/YfiT-like Superfamily. Based on structural similarity using the Superfamily program, we have determined 30 of 31 Staphylococcus aureus strains encode a single bacillithiol transferase from the DinB/YfiT-like Superfamily, while the remaining strain encodes two proteins. Methods We have cloned, purified, and confirmed the activity of a recombinant bacillithiol transferase (henceforth called BstA) encoded by the S. aureus Newman ORF NWMN_2591. Moreover, we have studied the saturation kinetics and substrate specificity of this enzyme using in vitro biochemical assays. Results BstA was found to be active with the co-substrate bacillithiol, but not with other low molecular weight thiols tested. BstA catalyzed bacillithiol conjugation to the model substrates monochlorobimane, 1-chloro-2,4-dinitrobenzene, and the antibiotic cerulenin. Several other molecules, including the antibiotic rifamycin S, were found to react directly with bacillithiol, but the addition of BstA did not enhance the rate of reaction. Furthermore, cells growing in nutrient rich medium exhibited low BstA activity. Conclusions BstA is a bacillithiol transferase from Staphylococcus aureus that catalyzes the detoxification of cerulenin. Additionally, we have determined that bacillithiol itself might be capable of directly detoxifying electrophilic molecules. General Significance BstA is an active bacillithiol transferase from Staphylococcus aureus Newman and is the first DinB/YfiT-like Superfamily member identified from this organism. Interestingly, BstA is highly divergent from Bacillus subtilis YfiT. PMID:24821014

  8. A dynamic CSTT model for the effects of added nutrients in Loch Creran, a shallow fjord

    NASA Astrophysics Data System (ADS)

    Laurent, Céline; Tett, Paul; Fernandes, Teresa; Gilpin, Linda; Jones, Ken

    2006-07-01

    Despite a tendency for the complexity of physical-biological models to increase, simple coupled models remain useful for some applications and can provide insights into crucial links between physical and biological processes. This argument is illustrated with an account of a simple 3-box model intended to help assess the capacity of fjords to assimilate nutrients from fish farms. The model, a dynamic version of the UK "Comprehensive Studies Task Team" (CSTT) steady-state model for eutrophication, was applied to Loch Creran (Scottish Western Highlands) and was implemented using Stella 8 and tested using historical data from 1975 (before the installation of a salmon farm) and field data collected in 2003, during the period of operation of the farm. The model's biological state variables are chlorophyll, dissolved inorganic nitrogen (DIN) and dissolved inorganic phosphorus (DIP), and it includes a simple run-off model to convert rainfall into river discharge. The physical processes involved in exchange between the loch and the adjacent waters of the Firth of Lorne were parameterised as a constant daily exchange rate. Between 1975 and 2003, local inputs of nutrient increased but, despite this, there was little apparent increase in nutrient concentrations in the loch, and observed chlorophyll concentrations decreased substantially. Model simulations of chlorophyll and DIN agreed well with observations in 1975, as did DIN simulations in 2003. However, simulated chlorophyll was overestimated in 2003. Some of the agreement between observations and simulations come from the use of observed boundary conditions to force the model. However, even when boundary conditions are subtracted from simulations and observations, the simulations in most cases retain a significant correlation with observations, demonstrating that the model's 'interior' processes do add to its ability to replicate conditions in the loch.

  9. Fluxes of nutrients from the tropical River Hooghly at the land ocean boundary of Sundarbans, NE Coast of Bay of Bengal, India

    NASA Astrophysics Data System (ADS)

    Mukhopadhyay, S. K.; Biswas, H.; De, T. K.; Jana, T. K.

    2006-08-01

    The Ganges drains much of the southern slopes of the Himalayas and yields high-suspended sediment load during the monsoon. The Hooghly estuary, the first deltaic offshoot of the Ganges and flows through the western part of the Sundarbans mangrove forest is a source for inorganic nutrients due to the high input of litter and sediment associated nutrients that are released during estuarine transport. Dissolved inorganic carbon (DIC), dissolved inorganic nitrogen (DIN), dissolved reactive phosphate (DRP) and silicate budgets and fluxes of the coastal zone of the Hooghly River system have been done by biogeochemical modeling and their annual fluxes were calculated to be 230 × 10 9 mol (2.76 × 10 6 t), 4705 × 10 6 mol (65.8 × 10 3 t), 415 × 10 6 mol (12.8 × 10 3 t), 15.28 × 10 9 mol (42.8 × 10 3 t), respectively. Out of the total transport, monsoonal runoff could account 64% for DIC, 71% for DIN and 76% for both DRP and silicate. Annual load of sediment out of the estuary to the NE coast of Bay of Bengal was estimated to be 65.19 × 10 6 t. During the estuarine transport 7.5% of DIC and 7.0% of silicate were removed while addition for DIN and DRP were found to be 59% and 44%, respectively. Occurrence of light limited conditions and auto-heterotrophic coupling within the estuary results regeneration of nutrients from organic matter originated from external source. Comparison was made with the estimates of nutrient fluxes through the some mangrove dominated Southeast Asian estuaries.

  10. Acid rain mitigation experiment shifts a forested watershed from a net sink to a net source of nitrogen.

    PubMed

    Rosi-Marshall, Emma J; Bernhardt, Emily S; Buso, Donald C; Driscoll, Charles T; Likens, Gene E

    2016-07-01

    Decades of acid rain have acidified forest soils and freshwaters throughout montane forests of the northeastern United States; the resulting loss of soil base cations is hypothesized to be responsible for limiting rates of forest growth throughout the region. In 1999, an experiment was conducted that reversed the long-term trend of soil base cation depletion and tested the hypothesis that calcium limits forest growth in acidified soils. Researchers added 1,189 kg Ca(2+) ha(-1) as the pelletized mineral wollastonite (CaSiO3) to a 12-ha forested watershed within the Hubbard Brook Experimental Forest in the White Mountains of New Hampshire. Significant increases in the pH and acid-neutralizing capacity of soils and streamwater resulted, and the predicted increase in forest growth occurred. An unanticipated consequence of this acidification mitigation experiment began to emerge a decade later, with marked increases in dissolved inorganic nitrogen (DIN) exports in streamwater from the treated watershed. By 2013, 30-times greater DIN was exported from this base-treated watershed than from adjacent reference watersheds, and DIN exports resulting from this experiment match or exceed earlier reports of inorganic N losses after severe ice-storm damage within the study watershed. The discovery that CaSiO3 enrichment can convert a watershed from a sink to a source of N suggests that numerous potential mechanisms drive watershed N dynamics and provides new insights into the influence of acid deposition mitigation strategies for both carbon cycling and watershed N export. PMID:27335456

  11. Relationship between two Solomon Islands Earthquakes in 2007 (M8.1), 2010 (M7.1), and Seismic Gap along the Subduction Zone, Revealed by ALOS/PALSAR

    NASA Astrophysics Data System (ADS)

    Miyagi, Y.; Ozawa, T.

    2010-12-01

    The Solomon Islands are located in the southwest of the Pacific Ocean. The Australian, Woodlark, and Solomon Sea plates subduct toward the northeast beneath the Pacific plate. Interaction among these four plates cause complicated tectonics around the Solomon Islands, and have caused interplate earthquakes in the subduction zone (e.g. Lay and Kanamori, 1980; Xu and Schwarts, 1993). On April 1, 2007 (UTC), an M8.1 interplate earthquake occurred in the subduction zone between the Pacific Plate and the Australian Plate. This earthquake was accompanied by a large tsunami and caused considerable damage in the area. The Japan Aerospace Exploration Agency (JAXA) carried out emergency observations using the Phased Array type L-band Synthetic Aperture Rader (PALSAR) installed on Advanced Land Observing Satellite (ALOS), and detected more than 2m of maximum displacement using differential interferometric SAR (DInSAR) technique. Miyagi et al. (2009) estimated a slip distribution of the seismic fault mainly from the PALSAR/DInSAR data and suggested that most of a seismic gap was filled by the 2007 events, but a small seismic gap connecting to an Mw7.0-sized earthquake still remained. On January 3, 2010, an M7.1 earthquake occurred in the vicinity of the remnant seismic gap. ALOS/PALSAR observed epicentral area both before and after the event, and detected crustal deformation associated with the earthquake. We inferred fault model using the PALSAR/DInSAR data and concluded that the 2010 event was the supposed thrust earthquake filling the remnant seismic gap. A distribution of coulomb failure stress change in the epicentral area after the 2007 event suggested the possibility that the 2010 event was triggered by the 2007 earthquake.

  12. Acid rain mitigation experiment shifts a forested watershed from a net sink to a net source of nitrogen.

    PubMed

    Rosi-Marshall, Emma J; Bernhardt, Emily S; Buso, Donald C; Driscoll, Charles T; Likens, Gene E

    2016-07-01

    Decades of acid rain have acidified forest soils and freshwaters throughout montane forests of the northeastern United States; the resulting loss of soil base cations is hypothesized to be responsible for limiting rates of forest growth throughout the region. In 1999, an experiment was conducted that reversed the long-term trend of soil base cation depletion and tested the hypothesis that calcium limits forest growth in acidified soils. Researchers added 1,189 kg Ca(2+) ha(-1) as the pelletized mineral wollastonite (CaSiO3) to a 12-ha forested watershed within the Hubbard Brook Experimental Forest in the White Mountains of New Hampshire. Significant increases in the pH and acid-neutralizing capacity of soils and streamwater resulted, and the predicted increase in forest growth occurred. An unanticipated consequence of this acidification mitigation experiment began to emerge a decade later, with marked increases in dissolved inorganic nitrogen (DIN) exports in streamwater from the treated watershed. By 2013, 30-times greater DIN was exported from this base-treated watershed than from adjacent reference watersheds, and DIN exports resulting from this experiment match or exceed earlier reports of inorganic N losses after severe ice-storm damage within the study watershed. The discovery that CaSiO3 enrichment can convert a watershed from a sink to a source of N suggests that numerous potential mechanisms drive watershed N dynamics and provides new insights into the influence of acid deposition mitigation strategies for both carbon cycling and watershed N export.

  13. Effect of reduced winter precipitation and increased temperature on watershed solute flux, 1988-2002, Northern Michigan

    USGS Publications Warehouse

    Stottlemyer, R.; Toczydlowski, D.

    2006-01-01

    Since 1987 we have studied weekly change in winter (December-April) precipitation, snowpack, snowmelt, soil water, and stream water solute flux in a small (176-ha) Northern Michigan watershed vegetated by 65-85 year-old northern hardwoods. Our primary study objective was to quantify the effect of change in winter temperature and precipitation on watershed hydrology and solute flux. During the study winter runoff was correlated with precipitation, and forest soils beneath the snowpack remained unfrozen. Winter air temperature and soil temperature beneath the snowpack increased while precipitation and snowmelt declined. Atmospheric inputs declined for H+, NO 3- , NH 4+ , dissolved inorganic nitrogen (DIN), and SO 42- . Replicated plot-level results, which could not be directly extrapolated to the watershed scale, showed 90% of atmospheric DIN input was retained in surface shallow (<15 cm deep) soils while SO 42- flux increased 70% and dissolved organic carbon (DOC) 30-fold. Most stream water base cation (C B), HCO 3- , and Cl- concentrations declined with increased stream water discharge, K+, NO 3- , and SO 42- remained unchanged, and DOC and dissolved organic nitrogen (DON) increased. Winter stream water solute outputs declined or were unchanged with time except for NO 3- and DOC which increased. DOC and DIN outputs were correlated with the percentage of winter runoff and stream discharge that occurred when subsurface flow at the plot-level was shallow (<25 cm beneath Oi). Study results suggest that the percentage of annual runoff occurring as shallow lateral subsurface flow may be a major factor regulating solute outputs and concentrations in snowmelt-dominated ecosystems. ?? Springer 2006.

  14. Centimeter Cosmo-Skymed Range Measurements for Monitoring Ground Displacements

    NASA Astrophysics Data System (ADS)

    Fratarcangeli, F.; Nascetti, A.; Capaldo, P.; Mazzoni, A.; Crespi, M.

    2016-06-01

    The SAR (Synthetic Aperture Radar) imagery are widely used in order to monitor displacements impacting the Earth surface and infrastructures. The main remote sensing technique to extract sub-centimeter information from SAR imagery is the Differential SAR Interferometry (DInSAR), based on the phase information only. However, it is well known that DInSAR technique may suffer for lack of coherence among the considered stack of images. New Earth observation SAR satellite sensors, as COSMO-SkyMed, TerraSAR-X, and the coming PAZ, can acquire imagery with high amplitude resolutions too, up to few decimeters. Thanks to this feature, and to the on board dual frequency GPS receivers, allowing orbits determination with an accuracy at few centimetres level, the it was proven by different groups that TerraSAR-X imagery offer the capability to achieve, in a global reference frame, 3D positioning accuracies in the decimeter range and even better just exploiting the slant-range measurements coming from the amplitude information, provided proper corrections of all the involved geophysical phenomena are carefully applied. The core of this work is to test this methodology on COSMO-SkyMed data acquired over the Corvara area (Bolzano - Northern Italy), where, currently, a landslide with relevant yearly displacements, up to decimeters, is monitored, using GPS survey and DInSAR technique. The leading idea is to measure the distance between the satellite and a well identifiable natural or artificial Persistent Scatterer (PS), taking in account the signal propagation delays through the troposphere and ionosphere and filtering out the known geophysical effects that induce periodic and secular ground displacements. The preliminary results here presented and discussed indicate that COSMO-SkyMed Himage imagery appear able to guarantee a displacements monitoring with an accuracy of few centimetres using only the amplitude data, provided few (at least one) stable PS's are available around the

  15. Serological markers of enterocyte damage and apoptosis in patients with celiac disease, autoimmune diabetes mellitus and diabetes mellitus type 2.

    PubMed

    Hoffmanová, I; Sánchez, D; Hábová, V; Anděl, M; Tučková, L; Tlaskalová-Hogenová, H

    2015-01-01

    Impairment of mucosal barrier integrity of small intestine might be causative in immune-mediated gastrointestinal diseases. We tested the markers of epithelial apoptosis - cytokeratin 18 caspase-cleaved fragment (cCK-18), and enterocyte damage - intestinal fatty acid-binding protein (I-FABP) and soluble CD14 (sCD14) in sera of patients with untreated celiac disease (CLD), those on gluten-free diet (CLD-GFD), patients with autoimmune diabetes mellitus (T1D), T1D with insulitis (T1D/INS), and diabetes mellitus type 2 (T2D). We found elevated levels of cCK-18 (P<0.001), I-FABP (P<0.01) and sCD14 (P<0.05) in CLD when compared to healthy controls. However, the levels of cCK-18 (P<0.01) and I-FABP (P<0.01) in CLD-GFD were higher when compared with controls. Interestingly, elevated levels of cCK-18 and I-FABP were found in T2D and T1D (P<0.001), and T1D/INS (P<0.01, P<0.001). Twenty-two out of 43 CLD patients were seropositive for cCK-18, 19/43 for I-FABP and 11/43 for sCD14; 9/30 of T2D patients were positive for cCK-18 and 5/20 of T1D/INS for sCD14, while in controls only 3/41 were positive for cCK-18, 3/41 for I-FABP and 1/41 for sCD14. We documented for the first time seropositivity for sCD14 in CLD and potential usefulness of serum cCK-18 and I-FABP as markers of gut damage in CLD, CLD-GFD, and diabetes.

  16. Evidence for sensitivity of dune wetlands to groundwater nutrients.

    PubMed

    Rhymes, Jennifer; Wallace, Hilary; Fenner, Nathalie; Jones, Laurence

    2014-08-15

    Dune slacks are seasonal wetlands, high in biodiversity, which experience considerable within-year and between-year variations in water-table. They are subject to many pressures including climate change, land use change and eutrophication. Despite their biological importance and the threats facing them, the hydrological and nutrient parameters that influence their soil properties and biodiversity are poorly understood and there have been no empirical studies to date testing for biological effects in dune systems resulting from groundwater nutrients at low concentrations. In this study we examined the impact of groundwater nutrients on water chemistry, soil chemistry and vegetation composition of dune slacks at three distance classes (0-150 m, 150-300 m, 300-450 m) away from known (off-site) nutrient sources at Aberffraw dunes in North Wales, whilst accounting for differences in water-table regime. Groundwater nitrate and dissolved inorganic nitrogen (DIN) and soil nitrate and nitrite all had significantly higher concentrations closest to the nutrient source. Multivariate analysis showed that although plant species composition within this site was primarily controlled by water table depth and water table fluctuation, nitrogen from groundwater also influenced species composition, independently of water table and soil development. A model containing all hydrological parameters explained 17% of the total species variance; an additional 7% was explained following the addition of NO3 to this model. Areas exposed to elevated, but still relatively low, groundwater nutrient concentrations (mean 0.204 mg/L+/-0.091 of DIN) had greater abundance of nitrophilous species and fewer basipholous species than in areas with lower concentrations. This shows that clear biological impact occurs below previously suggested DIN thresholds of 0.20-0.40 (mg/L).

  17. The characteristics of nutrients and eutrophication in the Pearl River estuary, South China.

    PubMed

    Huang, X P; Huang, L M; Yue, W Z

    2003-01-01

    In the spring of 1998, 24-h time series and synchronization of vertical profiles of NO(3)-N, NO(2)-N, NH(3)-N, PO(4)-P, chlorophyll a, suspended substance, salinity, temperature and other chemical parameters were taken at 10 stations in the Pearl River estuary in order to analyze the status and characteristics of nutrients and eutrophication. The results indicated that dissolved inorganic nitrogen (DIN) mainly came from the four river channels in the main estuary, and NO(3)-N was the main form of DIN in most area. The concentration of DIN was general above 0.30 mg l(-1) in the estuary, and more than 0.50 mgl(-1) in most part. Phosphate from four river channels was not the main sources, but land-based sources from the area near Shenzhen Bay or along the estuary were obvious, and other land-based sources outside the estuary brought by coastal current and flood tide current were also the main contributions. The concentration of phosphate was generally about 0.015 mg l(-1) except the area near Shenzhen Bay. The ratio of N:P was generally high, and it was higher in the north than in the south. The highest ratio was higher than 300, and the lowest one was over 30. The concentration of chlorophyll a was about 0.8-7.8 mg m(-3), and turbidity and phosphate may be the main two limiting factors for algal bloom in the estuary. The concentration of nutrients decreased slightly in the past decade, but still stayed at a high level. The nutrients mainly came from domestic sewage, industrial wastewater, agriculture fertilizer and marine culture in the Pearl River estuary.

  18. [Nutrient composition changes in coastal waters of Tangshan Bay, Hebei, China under anthropogenic influence].

    PubMed

    Li, Zhi-wei; Cui, Li-tuo

    2016-01-01

    Based on the principal component analysis (PCA), data from 25 marine monitoring stations in Tangshan Bay from 1995 to 2012 were collected to study the change of nutrient composition in Tangshan Bay under anthropogenic influence. Results showed that the inorganic nitrogen (DIN) presented an obvious increase trend in the near 20 years, while the PO₄³⁻-P and SiO₃²⁻-Si presented a decrease trend. The average N:P ratio increased from 3.0 in 1995 to 26.0 in 2012, but the average Si:N ratio decreased, indicating the nutrient structure in seawater had substantially changed in the near 20 years. According to the results of PCA, the change of water quality was identified. The analysis extracted the first two principal components (PC). PC1 was associated with DIN, NO₃⁻-N, NH₄⁺-N, PO₄³⁻-P and NO₂⁻-N, which explained 71.5% of the variance. PC2 was characterized by Chl a and SiO₃²⁻-Si, which explained 21.8% of the variance. It indicated that the water quality of Tangshan bay was closely related to DIN and PO₄³⁻-P. The two principal component scores revealed the interannual change trend of water quality in the Tangshan Bay under anthropogenic influence, which changed from the N limitation before development and at early stage of development (1995-2005) to the P limitation after development (since 2007). The nutrient composition in Tangshan Bay had changed significantly under anthropogenic influence, therefore, special attention is needed on the the change of nutrients in seawater of Tangshan Bay, especially the increase of inorganic nitrogen content. PMID:27228623

  19. The Origin of Mutants Under Selection: How Natural Selection Mimics Mutagenesis (Adaptive Mutation).

    PubMed

    Maisnier-Patin, Sophie; Roth, John R

    2015-07-01

    Selection detects mutants but does not cause mutations. Contrary to this dictum, Cairns and Foster plated a leaky lac mutant of Escherichia coli on lactose medium and saw revertant (Lac(+)) colonies accumulate with time above a nongrowing lawn. This result suggested that bacteria might mutagenize their own genome when growth is blocked. However, this conclusion is suspect in the light of recent evidence that revertant colonies are initiated by preexisting cells with multiple copies the conjugative F'lac plasmid, which carries the lac mutation. Some plated cells have multiple copies of the simple F'lac plasmid. This provides sufficient LacZ activity to support plasmid replication but not cell division. In nongrowing cells, repeated plasmid replication increases the likelihood of a reversion event. Reversion to lac(+) triggers exponential cell growth leading to a stable Lac(+) revertant colony. In 10% of these plated cells, the high-copy plasmid includes an internal tandem lac duplication, which provides even more LacZ activity—sufficient to support slow growth and formation of an unstable Lac(+) colony. Cells with multiple copies of the F'lac plasmid have an increased mutation rate, because the plasmid encodes the error-prone (mutagenic) DNA polymerase, DinB. Without DinB, unstable and stable Lac(+) revertant types form in equal numbers and both types arise with no mutagenesis. Amplification and selection are central to behavior of the Cairns-Foster system, whereas mutagenesis is a system-specific side effect or artifact caused by coamplification of dinB with lac. Study of this system has revealed several broadly applicable principles. In all populations, gene duplications are frequent stable genetic polymorphisms, common near-neutral mutant alleles can gain a positive phenotype when amplified under selection, and natural selection can operate without cell division when variability is generated by overreplication of local genome subregions.

  20. Coseismic liquefaction phenomenon analysis by COSMO-SkyMed: 2012 Emilia (Italy) earthquake

    NASA Astrophysics Data System (ADS)

    Chini, Marco; Albano, Matteo; Saroli, Michele; Pulvirenti, Luca; Moro, Marco; Bignami, Christian; Falcucci, Emanuela; Gori, Stefano; Modoni, Giuseppe; Pierdicca, Nazzareno; Stramondo, Salvatore

    2015-07-01

    The liquefaction phenomenon that occurred in the coseismic phase of the May 20, 2012 Emilia (Italy) earthquake (ML 5.9) is investigated. It was induced by the water pressure increase in the buried and confined sand layers. The level-ground liquefaction was the result of a chaotic ground oscillation caused by the earthquake shaking and the observed failures were due to the upward water flow caused by the excess of pore pressures. We exploited the capability of the differential synthetic aperture radar interferometry (DInSAR) technique to detect soil liquefactions and estimate their surface displacements, as well as the high sensitivity to surface changes of complex coherence, SAR backscattering and intensity correlation. To this aim, a set of four COSMO-SkyMed X-band SAR images, covering the period April 1-June 6, 2012, was used. Geological-geotechnical analysis was also performed in order to ascertain if the detected SAR-based surface effects could be due to the compaction induced by liquefaction of deep sandy layers. In this regards, the results obtained from 13 electrical cone penetrometer tests show the presence of a fine to medium sandy layer at depths, ranging between 9 and 13 m, which probably liquefied during the earthquake, inducing vertical displacements between 3 and 16 cm. The quantitative results from geological-geotechnical analysis and the surface punctual effects measured by DInSAR are in good agreement, even if some differences are present, probably ascribable to the local thickness and depth variability of the sandy layer, or to lack of deformation detection due to DInSAR decorrelation. The adopted approach permitted us to define the extent of the areas that underwent liquefaction and to quantify the local subsidence related to these phenomena. The latter achievement provides useful information that must be considered in engineering practices, in terms of expected vertical deformations.

  1. Materials Selection Criteria for Nuclear Power Applications: A Decision Algorithm

    NASA Astrophysics Data System (ADS)

    Rodríguez-Prieto, Álvaro; Camacho, Ana María; Sebastián, Miguel Ángel

    2016-02-01

    An innovative methodology based on stringency levels is proposed in this paper and improves the current selection method for structural materials used in demanding industrial applications. This paper describes a new approach for quantifying the stringency of materials requirements based on a novel deterministic algorithm to prevent potential failures. We have applied the new methodology to different standardized specifications used in pressure vessels design, such as SA-533 Grade B Cl.1, SA-508 Cl.3 (issued by the American Society of Mechanical Engineers), DIN 20MnMoNi55 (issued by the German Institute of Standardization) and 16MND5 (issued by the French Nuclear Commission) specifications and determine the influence of design code selection. This study is based on key scientific publications on the influence of chemical composition on the mechanical behavior of materials, which were not considered when the technological requirements were established in the aforementioned specifications. For this purpose, a new method to quantify the efficacy of each standard has been developed using a deterministic algorithm. The process of assigning relative weights was performed by consulting a panel of experts in materials selection for reactor pressure vessels to provide a more objective methodology; thus, the resulting mathematical calculations for quantitative analysis are greatly simplified. The final results show that steel DIN 20MnMoNi55 is the best material option. Additionally, more recently developed materials such as DIN 20MnMoNi55, 16MND5 and SA-508 Cl.3 exhibit mechanical requirements more stringent than SA-533 Grade B Cl.1. The methodology presented in this paper can be used as a decision tool in selection of materials for a wide range of applications.

  2. Factors controlling aquatic dissolved inorganic nitrogen removal and export in suburban watersheds

    NASA Astrophysics Data System (ADS)

    Mineau, M.; Wollheim, W. M.; Stewart, R.; Daley, M.; McDowell, W. H.

    2013-12-01

    Human activity has accelerated the nitrogen (N) cycle and enriched the landscape with N which can result in eutrophication, especially in coastal zones where N is typically limiting. N exported to coastal zones is a function of both N loading to aquatic systems and N removal in transit through the river network. To determine drivers of dissolved inorganic nitrogen (DIN) removal and export from suburban river networks, we compared 2 well-studied suburban New-England watersheds. The Lamprey River watershed (474 km2) in NH has a mean population density of 53 inhabitants per km2 and feeds into the Great Bay estuary which is designated as N impaired. The Ipswich River (400 km2) in MA has a much higher population density with 302 inhabitants per km2 and feeds into the Plum Island estuary, which is not N impaired. Median (2000 - 2009) watershed DIN export was 171 kg km-2 y-1 for the Ipswich and 77 kg km-2 y-1 for the Lamprey. We used the Framework for Aquatic Modeling in the Earth System (FrAMES) to evaluate the relative importance of anthropogenic N loading and river network DIN processing in determining N export from these watersheds. FrAMES is a spatially distributed and time varying coupled hydrologic and biogeochemical model for river networks. We hypothesized that greater N export relative to population density in the Lamprey watershed was due in part to less aquatic N processing caused by interactions among: 1. The distribution of development/sources in the watershed (i.e. mean flow path length N has to travel), and 2. The area and distribution of intact fluvial wetlands in the watershed. We conducted a sensitivity analysis to determine the relative importance of these factors in limiting aquatic N removal in the Lamprey river watershed. Our results suggest that the distribution of loading within a river system has important influence on nutrient export to coastal zones.

  3. In-stream biotic control on nutrient biogeochemistry in a forested sheadwater tream, West Fork of Walker Branch

    SciTech Connect

    Roberts, Brian J; Mulholland, Patrick J

    2007-01-01

    A growing body of evidence demonstrates the importance of in-stream processing in regulating nutrient export, yet the influence of temporal variability in stream metabolism on net nutrient uptake has not been explicitly addressed. Streamwater DIN and SRP concentrations in Walker Branch, a first-order deciduous forest stream in eastern Tennessee, show a repeated pattern of annual maxima in summer and biannual minima in spring and autumn. Temporal variations in catchment hydrologic flowpaths result in lower winter and higher summer nutrient concentrations, but do not explain the spring and autumn nutrient minima. Ambient nutrient uptake rates were measured 2-3 times per week over an 18-mo period and compared to daily rates of gross primary production (GPP) and ecosystem respiration (ER) to examine the influence of in-stream biotic activity on nutrient export. GPP and ER rates explained 85% of the variation in net DIN retention with high net NO3- uptake (and lower net NH4+ release) rates occurring during spring and autumn and net DIN release in summer. Diel nutrient concentration patterns were examined several times throughout the year to determine the relative importance of autotrophic and heterotrophic activity on net nutrient uptake. High spring GPP corresponded to daily decreases in NO3- over the illuminated hours resulting in high diel NO3- amplitude which dampened as the canopy closed. GPP explained 91% of the variance in diel NO3- amplitude. In contrast, the autumn nutrient minima was largely explained by heterotrophic respiration since GPP remained low and little diel NO3- variation was observed during the autumn.

  4. The relationship between phytoplankton distribution and water column characteristics in North West European shelf sea waters.

    PubMed

    Fehling, Johanna; Davidson, Keith; Bolch, Christopher J S; Brand, Tim D; Narayanaswamy, Bhavani E

    2012-01-01

    Phytoplankton underpin the marine food web in shelf seas, with some species having properties that are harmful to human health and coastal aquaculture. Pressures such as climate change and anthropogenic nutrient input are hypothesized to influence phytoplankton community composition and distribution. Yet the primary environmental drivers in shelf seas are poorly understood. To begin to address this in North Western European waters, the phytoplankton community composition was assessed in light of measured physical and chemical drivers during the "Ellett Line" cruise of autumn 2001 across the Scottish Continental shelf and into adjacent open Atlantic waters. Spatial variability existed in both phytoplankton and environmental conditions, with clear differences not only between on and off shelf stations but also between different on shelf locations. Temperature/salinity plots demonstrated different water masses existed in the region. In turn, principal component analysis (PCA), of the measured environmental conditions (temperature, salinity, water density and inorganic nutrient concentrations) clearly discriminated between shelf and oceanic stations on the basis of DIN:DSi ratio that was correlated with both salinity and temperature. Discrimination between shelf stations was also related to this ratio, but also the concentration of DIN and DSi. The phytoplankton community was diatom dominated, with multidimensional scaling (MDS) demonstrating spatial variability in its composition. Redundancy analysis (RDA) was used to investigate the link between environment and the phytoplankton community. This demonstrated a significant relationship between community composition and water mass as indexed by salinity (whole community), and both salinity and DIN:DSi (diatoms alone). Diatoms of the Pseudo-nitzschia seriata group occurred at densities potentially harmful to shellfish aquaculture, with the potential for toxicity being elevated by the likelihood of DSi limitation of

  5. The relationship between phytoplankton distribution and water column characteristics in North West European shelf sea waters.

    PubMed

    Fehling, Johanna; Davidson, Keith; Bolch, Christopher J S; Brand, Tim D; Narayanaswamy, Bhavani E

    2012-01-01

    Phytoplankton underpin the marine food web in shelf seas, with some species having properties that are harmful to human health and coastal aquaculture. Pressures such as climate change and anthropogenic nutrient input are hypothesized to influence phytoplankton community composition and distribution. Yet the primary environmental drivers in shelf seas are poorly understood. To begin to address this in North Western European waters, the phytoplankton community composition was assessed in light of measured physical and chemical drivers during the "Ellett Line" cruise of autumn 2001 across the Scottish Continental shelf and into adjacent open Atlantic waters. Spatial variability existed in both phytoplankton and environmental conditions, with clear differences not only between on and off shelf stations but also between different on shelf locations. Temperature/salinity plots demonstrated different water masses existed in the region. In turn, principal component analysis (PCA), of the measured environmental conditions (temperature, salinity, water density and inorganic nutrient concentrations) clearly discriminated between shelf and oceanic stations on the basis of DIN:DSi ratio that was correlated with both salinity and temperature. Discrimination between shelf stations was also related to this ratio, but also the concentration of DIN and DSi. The phytoplankton community was diatom dominated, with multidimensional scaling (MDS) demonstrating spatial variability in its composition. Redundancy analysis (RDA) was used to investigate the link between environment and the phytoplankton community. This demonstrated a significant relationship between community composition and water mass as indexed by salinity (whole community), and both salinity and DIN:DSi (diatoms alone). Diatoms of the Pseudo-nitzschia seriata group occurred at densities potentially harmful to shellfish aquaculture, with the potential for toxicity being elevated by the likelihood of DSi limitation of

  6. A Synergy Method to Improve Ensemble Weather Predictions and Differential SAR Interferograms

    NASA Astrophysics Data System (ADS)

    Ulmer, Franz-Georg; Adam, Nico

    2015-11-01

    A compensation of atmospheric effects is essential for mm-sensitivity in differential interferometric synthetic aperture radar (DInSAR) techniques. Numerical weather predictions are used to compensate these disturbances allowing a reduction in the number of required radar scenes. Practically, predictions are solutions of partial differential equations which never can be precise due to model or initialisation uncertainties. In order to deal with the chaotic nature of the solutions, ensembles of predictions are computed. From a stochastic point of view, the ensemble mean is the expected prediction, if all ensemble members are equally likely. This corresponds to the typical assumption that all ensemble members are physically correct solutions of the set of partial differential equations. DInSAR allows adding to this knowledge. Observations of refractivity can now be utilised to check the likelihood of a solution and to weight the respective ensemble member to estimate a better expected prediction. The objective of the paper is to show the synergy between ensemble weather predictions and differential interferometric atmospheric correction. We demonstrate a new method first to compensate better for the atmospheric effect in DInSAR and second to estimate an improved numerical weather prediction (NWP) ensemble mean. Practically, a least squares fit of predicted atmospheric effects with respect to a differential interferogram is computed. The coefficients of this fit are interpreted as likelihoods and used as weights for the weighted ensemble mean. Finally, the derived weighted prediction has minimal expected quadratic errors which is a better solution compared to the straightforward best-fitting ensemble member. Furthermore, we propose an extension of the algorithm which avoids the systematic bias caused by deformations. It makes this technique suitable for time series analysis, e.g. persistent scatterer interferometry (PSI). We validate the algorithm using the well known

  7. Spatial patterns of atmospheric deposition of nitrogen and sulfur using ion-exchange resin collectors in Rocky Mountain National Park, USA

    USGS Publications Warehouse

    Clow, David W.; Roop, Heidi; Nanus, Leora; Fenn, Mark; Sexstone, Graham A.

    2015-01-01

    Lakes and streams in Class 1 wilderness areas in the western United States (U.S.) are at risk from atmospheric deposition of nitrogen (N) and sulfur (S), and protection of these resources is mandated under the Federal Clean Air Act and amendments. Assessment of critical loads, which are the maximum exposure to pollution an area can receive without adverse effects on sensitive ecosystems, requires accurate deposition estimates. However, deposition is difficult and expensive to measure in high-elevation wilderness, and spatial patterns in N and S deposition in these areas remain poorly quantified. In this study, ion-exchange resin (IER) collectors were used to measure dissolved inorganic N (DIN) and S deposition during June 2006–September 2007 at approximately 20 alpine/subalpine sites spanning the Continental Divide in Rocky Mountain National Park. Results indicated good agreement between deposition estimated from IER collectors and commonly used wet + dry methods during summer, but poor agreement during winter. Snowpack sampling was found to be a more accurate way of quantifying DIN and S deposition during winter. Summer DIN deposition was significantly greater on the east side of the park than on the west side (25–50%; p ≤ 0.03), consistent with transport of pollutants to the park from urban and agricultural areas to the east. Sources of atmospheric nitrate (NO3−) were examined using N isotopes. The average δ15N of NO3− from IER collectors was 3.5‰ higher during winter than during summer (p < 0.001), indicating a seasonal shift in the relative importance of regional NOxsources, such as coal combustion and vehicular sources of atmospheric NO3−. There were no significant differences in δ15N of NO3− between east and west sides of the park during summer or winter (p = 0.83), indicating that the two areas may have similar sources of atmospheric NO3−. Results from this study indicate that a combination of IER collectors and snowpack

  8. Observation and extirpation of a giant-size type-B2 thymoma IIb with its histological, macroscopic, and computer tomogram correlate, and literature review

    PubMed Central

    de Bucourt, Maximilian; Swierzy, Marc; Dankof, Anja; Teichgräber, Ulf; Rückert, Jens-Carsten

    2010-01-01

    This report describes the interdisciplinary approach and solving algorithm of a DIN 9001:2000 certified tumor board in managing a giant-size type-B2 thymoma IIb in an elderly patient. The process of managing the thymoma with specialists of surgery, internal medicine, radiology, and pathology until finally extirpation and continuous follow-up is described. Respective computerized tomography scans, histology, macro-pathology, and operative pictures of the case are provided as well as an upto-date literature review. PMID:21139832

  9. Nutrient inputs from the watershed and coastal eutrophication in the Florida Keys

    SciTech Connect

    LaPointe, B.E. ); Clark, M.W. )

    1992-12-01

    Widespread use of septic tanks in the Florida Keys increase the nutrient concentrations of limestone ground waters that discharge into shallow nearshore waters, resulting in coastal eutrophication. This study characterizes watershed nutrient inputs, transformations, and effects along a land-sea gradient stratified into four ecosystems that occur with increasing distance from land: manmade canal systems, seagrass meadows, patch reefs, and offshore bank reefs. Soluble reactive phosphorus (SRP), the primary limiting nutrient, was significantly elevated in canal systems, while dissolved inorganic nitrogen (DIN; NH[sub 4][sup =] and NO[sub 3][sup [minus

  10. The yield of chlorophyll from nitrogen: a comparison between the shallow Ria Formosa lagoon and the deep oceanic conditions at Sagres along the southern coast of Portugal

    NASA Astrophysics Data System (ADS)

    Edwards, Vivien; Icely, John; Newton, Alice; Webster, Ruth

    2005-02-01

    The yield of chlorophyll from dissolved inorganic nitrogen (DIN) has been shown to be a potentially useful parameter for predicting eutrophication, particularly, in the northerly, coastal waters of the North East Atlantic (NEA). This study investigates whether this parameter might also be appropriate for the southerly, coastal waters of the NEA. Nitrogen enrichment experiments were carried out using microcosms to determine the microplanktonic yield of chlorophyll from DIN in waters from the Ria Formosa (April 2002) and from Sagres (September 2002) on the south coast of Portugal. Continuous culture techniques enabled experiments to be run for 7 days after enrichment so that changes in the cumulative yield over time could be calculated. Yields from the Sagres experiment were consistently higher than those from the Ria Formosa experiment, with respective maximum yields of 4.7 and 2.1 μg chl (μmol N) -1, and respective steady-state yields of 3.1 and 0.9 μg chl (μmol N) -1. In addition, regressions carried out on historical data sets from the two study sites showed poor correlation between chlorophyll and nitrate. Other differences between the microcosm experiments at the two sites, included: background concentrations of DIN, silicate and phosphate that were, respectively, 5.6 μM, 8.1 μM, and 0.3 μM higher in the Ria; chlorophyll concentrations at Sagres that were double those of the Ria; accumulation of particulate nitrogen that was both more rapid and more substantial at Sagres; a different community structure for the diatoms at the two sites; more numerous autotrophic dinoflagellates, flagellates and cyanobacteria, as well as more numerous protozoan grazers, at Sagres. These differences may explain why the yield of chlorophyll from DIN at Sagres is one of the highest reported in the literature. This yield parameter requires further study under a range of seasonal conditions and with a range of microplankton communities before it could be considered useful for

  11. Femtoquímica: reacciones en tiempo real, ?`Posibles aplicaciones en Astrofísica?

    NASA Astrophysics Data System (ADS)

    Douhal, Abderrazzak

    En esta conferencia, se mostrarán resultados de medidas en escala del femtosegundo por la primera vez obtenidos en España. Los sistemas elegidos muestran dinámicas que varían de 50 fs a centenas de picosegundo. La técnica usada (sumación de frecuencia) permite ver como ocurren las reacciones químicas y biológicas en tiempo real de reacciones. Su aplicación al estudio de las reacciones fotónicas en el espacio es evidente.

  12. Poultry manure runoff and its influence on fluorescence characteristics of dissolved organic matter (DOM)

    NASA Astrophysics Data System (ADS)

    Singh, S.; Dutta, S.; Inamdar, S. P.

    2013-12-01

    Land application of poultry manure as a substitute for synthetic fertilizer is a common practice in states like Delaware which have a surplus of this animal waste. However, this practice can generate large amounts of labile DOM and nutrients in agricultural runoff that can cause eutrophication of downstream aquatic ecosystems. We determined the concentrations of dissolved organic carbon (DOC) and dissolved inorganic nitrogen (DIN) and the quality of DOM for a cropland receiving poultry manure in the coastal plain soils of Delaware. Manure was applied at the rate of 9 Mg ha-1 in the spring (March 10) of 2010 to an agricultural field planted in corn. Sampling was performed for surface runoff and soil waters at four landscape positions - field edge, upper and lower riparian zones and the stream. Sampling was conducted for eight storm events, one before manure application and seven after (March through July spanning over 100 days). DOM quality was characterized using spectrofluorometric techniques and the development of a site-specific PARAFAC model. DOC and DIN concentrations in surface runoff ranged from 18.1 to 77.2 mg/l and 4.2 to 22.6 mg/l, respectively. The percent of protein-like and humic-like DOM in surface runoff ranged between 3.9 to 23.5% and 12.3 to 41.6%, respectively. Highest concentrations of DOC and DIN were observed at the field edge and lowest in the stream. Protein-like and humic-like DOM decreased from the field edge to stream in surface runoff and soil waters. Temporally, both humic-like and protein-like DOM showed significant increases in storm runoff following manure application. After manure application, humic-like DOM increased by 70% while protein-like DOM increased by more than 200% in surface runoff indicating elevated content of labile DOM in poultry manure. These concentrations remained high for more than 60 days following manure application. Protein-like DOM was significantly correlated with nitrate-nitrogen (r = 0.43; p < 0

  13. Consequences of winter upwelling events on biogeochemical and phytoplankton patterns in a western Galician ria (NW Iberian peninsula)

    NASA Astrophysics Data System (ADS)

    Prego, Ricardo; Guzmán-Zuñiga, Dafne; Varela, Manuel; deCastro, Maite; Gómez-Gesteira, Moncho

    2007-07-01

    The consequences of two upwelling events in mid- (MW) and late (LW) winter on biogeochemical and phytoplankton patterns were studied in the Pontevedra Ria and compared with the patterns measured under typical winter conditions and under a summer upwelling event. Thermohaline patterns measured during the mid-winter upwelling event (MW-up) revealed the intrusion of saltier seawater (35.9) into the ria associated with the Iberian Poleward Current (IPC). During the late-winter upwelling event (LW-up), the seawater which had welled up into the ria showed characteristics of the Eastern North Atlantic Central Water mass (ENACW). In both cases the measured water residence time (4 days during MW-up and 10 days during LW-up) was related to both meteorological and fluvial forcing. This residence time contrasts with that of summer upwelling (7 days) and with that estimated under unfavorable upwelling atmospheric conditions (2-4 weeks). During MW-up, the ria became poor in nutrients due to continental freshwater dilution, associated with the shorter residence time of the water, and the intrusion of IPC, which is a water body poor in nutrient salts: 2.9 μM of nitrate, 0.1 μM of phosphate and 1.5 μM of silicate. During this event, the ria exported 3.4 mol DIN s -1, compared with 6.9 mol DIN s -1 in non-upwelling conditions. Phytoplankton showed a uniform distribution throughout the ria, as during unfavorable upwelling conditions, and was characterized by the dominance of diatoms, mainly Nitzschia longissima and Skeletonema costatum. During LW-up, a nutrient depletion in the photic layer also occurred, but as a result of a phytoplankton spring bloom developing at this time. The ria was a nutrient trap where 4.1 mol DIN s -1 were processed by photosynthesis. This budget is three times higher than the one under non-upwelling conditions. In contrast with the MW-up, which had no effect on primary production, during LW-up the ria became more productive, although not as productive as

  14. Caos en sistemas clásico-cuánticos

    NASA Astrophysics Data System (ADS)

    Dirani, L. D.; Núñez, J. A.

    Una de las formas de estudiar la existencia de caos en el comportamiento de un sistema clásico-cuántico, es truncando el espacio de Hilbert del sistema cuántico. El objetivo de este trabajo es analizar como afecta dicho truncamiento en la dinámica del sistema. Para tal fin se propone un Hamiltoniano integrable, cuyos valores de expectación asociados a coordenadas y momentos cuánticos responden, por el teorema de Ehrenfest, a un sistema de dos osciladores clásicos con acoplamiento lineal.

  15. El problema de estabilidad de los sistemas Hamiltonianos multidimensionales

    NASA Astrophysics Data System (ADS)

    Cincotta, P. M.

    Se revisarán los aspectos básicos del problema de estabilidad de sistemans Hamiltonianos N-dimensionales, haciendo especial énfasis en los posibles mecanismos que dan lugar a la aparición de ``caos": overlap de resonancias, difusión de Arnol'd y otros procesos difusivos alternativos. Se mencionarán los aspectos aún no resueltos sobre la estabilidad de los sistemas con N > 2. Finalmente, se discutirá cuáles de estos mecanismos podrían tener alguna relevancia en la dinámica de sistemas estelares y planetarios.

  16. Adopting Industry Standards for Control Systems Within Advanced Life Support

    NASA Technical Reports Server (NTRS)

    Young, James Scott; Boulanger, Richard

    2002-01-01

    This paper gives a description of OPC (Object Linking and Embedding for Process Control) standards for process control and outlines the experiences at JSC with using these standards to interface with I/O hardware from three independent vendors. The I/O hardware was integrated with a commercially available SCADA/HMI software package to make up the control and monitoring system for the Environmental Systems Test Stand (ESTS). OPC standards were utilized for communicating with I/O hardware and the software was used for implementing monitoring, PC-based distributed control, and redundant data storage over an Ethernet physical layer using an embedded din-rail mounted PC.

  17. Final Report Navajo Transmission Project (NTP)

    SciTech Connect

    Bennie Hoisington; Steven Begay

    2006-09-14

    The Diné Power Authority is developing the Navajo Transmission Project (NTP) to relieve the constraints on the transmission of electricity west of the Four Corners area and to improve the operation flexibility and reliability of the extra-high-voltage transmission system in the region. The NTP creates the wholesale transmission capacity for more economical power transfers, sales, and purchases in the region. It will facilitate the development of Navajo energy resources, improve economic conditions on the Navajo Nation as well as allow DPA to participate in the western electrical utility industry.

  18. Nutrient fluctuations in the Quatipuru river: A macrotidal estuarine mangrove system in the Brazilian Amazonian basin

    NASA Astrophysics Data System (ADS)

    Pamplona, Fábio Campos; Paes, Eduardo Tavares; Nepomuceno, Aguinaldo

    2013-11-01

    The temporal and spatial variability of dissolved inorganic nutrients (NO3-, NO2-, NH4+, PO43- and DSi), total nitrogen (TN), total phosphorus (TP), nutrient ratios, suspended particulate matter (SPM) and Chlorophyll-a (Chl-a) were evaluated for the macrotidal estuarine mangrove system of the Quatipuru river (QUATIES), east Amazon coast, North Brazil. Temporal variability was assessed by fortnightly sampling at a fixed station within the middle portion of the estuary, from November 2009 to November 2010. Spatial variability was investigated from two field surveys conducted in November 2009 (dry season) and May 2010 (rainy season), along the salinity gradient of the system. The average DIN (NO3- + NO2- + NH4+) concentration of 9 μM in the dry season was approximately threefold greater in comparison to the rainy season. NH4+ was the main form of DIN in the dry season, while NO3- predominated in the rainy season. The NH4+ concentrations in the water column during the dry season are largely attributed to release by tidal wash-out of the anoxic interstitial waters of the surficial mangrove sediments. On the other hand, the higher NO3- levels during the wet season, suggested that both freshwater inputs and nitrification processes in the water column acted in concert. The river PO43- concentrations (DIP < 1 μM) were low and similar throughout the year. DIN was thus responsible for the major temporal and spatial variability of the dissolved DIN:DIP (N:P) molar ratios and nitrogen corresponded, in general, to the prime limiting nutrient for the sustenance of phytoplankton biomass in the estuary. During the dry season, P-limitation was detected in the upper estuary. PO43- adsorption to SPM was detected during the rainy season and desorption during the dry season along the salinity gradient. In general, the average Chl-a level (14.8 μg L-1) was 2.5 times higher in the rainy season than in the dry season (5.9 μg L-1). On average levels reached maxima at about 14 km from

  19. Examination of silicate limitation of primary production in Jiaozhou Bay, North China. III. Judgment method, rules and uniqueness of nutrient limitation among N, P, and Si

    NASA Astrophysics Data System (ADS)

    Dongfang, Yang; Zhenhui, Gao; Yu, Chen; Jing, Zhang; Peigang, Wang

    2003-06-01

    Analysis and comparison of Jiaozhou Bay data collected from May 1991 to February 1994 (12 seasonal investigations) provided by the Ecological Station of Jiaozhou Bay revealed the characteristic spatiotemporal variation of the ambient concentration Si∶DIN and Si∶16P ratios and the seasonal variation of Jiaozhou Bay Si∶DIN and Si∶16P ratios showing that the Si∶DIN ratios were <1 throughout the year in Jiaozhou Bay; and that the Si∶16P ratios were <1 throughout Jiaozhou Bay in spring, autumn and winter. The results proved that silicate limited phytoplankton growth in spring, autumn and winter in Jiaozhou Bay. Analysis of the Si∶DIN and Si∶P ratios showed that the nutrient Si has been limiting the growth of phytoplankton throughout the year in some Jiaozhou Bay waters; and that the silicate deficiency changed the phytoplankton assemblage structure. Analysis of discontinuous 1962 to 1998 nutrient data showed that there was no N or P limitation of phytoplankton growth in that period. The authors consider that the annual cyclic change of silicate limits phytoplankton growth in spring, autumn and winter every year in Jiaozhou Bay; and that in many Jiaozhou Bay waters where the phytoplankton as the predominant species need a great amount of silicate, analysis of the nutrients N or P limitation of phytoplankton growth relying only on the N and P nutrients and DIN∶P ratio could yield inaccurate conclusions. The results obtained by applying the rules of absolute and relative limitation fully support this view. The authors consider that the main function of nutrient silicon is to regulate and control the mechanism of the phytoplankton growth process in the ecological system in estuaries, bays and the sea. The authors consider that according to the evolution theory of Darwin, continuous environmental pressure gradually changes the phytoplankton assemblage's structure and the physiology of diatoms. Diatoms requiring a great deal of silicon either constantly

  20. Carbon Mineralization and Nitrogen Transformation During a Long Term Permafrost Incubation

    NASA Astrophysics Data System (ADS)

    Salmon, V. G.; Mack, M. C.; Schuur, E. A. G.

    2014-12-01

    As the limiting nutrient in warming high latitude ecosystems, nitrogen (N) is expected to play a key role in determining the future balance between permafrost carbon (C) losses and increased C sequestration by plants. During decomposition, nitrogen previously locked in soil organic matter is released into the soil solution in the form of dissolved organic molecules following depolymerization by extracellular enzymes. These dissolved organic forms of N can be consumed by the soil microbial community and incorporated in their biomass or mineralized if they are in excess of microbial demand. Once mineralized and released into the soil solutions, N can be lost from the soil system via denitrification. In well drained, low N tussock tundra, however, this pathway is unlikely. Dissolved inorganic N (DIN) and dissolved organic N (DON) are both biologically available to arctic plants. Understanding how the size of these pools changes with depth and continuing decomposition is therefore crucial to projecting the C balance of high latitude systems in a warmer future. N transformations associated with decomposition may differ greatly in surface soils, where a large labile C pool is present and soil has a high C:N ratio, versus deep soils that have a relatively small labile C pool and a lower C:N ratio. In this experiment, the relationship between N availability and C release from permafrost soils was addressed with a 225 day soil incubation performed at 15°C. Seven soil cores were collected from undisturbed, well drained tussock tundra and were partitioned into ten centimeter depth intervals to a depth of 80 cm. Carbon dioxide (CO2) fluxes were measured throughout the incubation period and were used to assess cumulative carbon losses and determine the size of the labile C pool. Destructive harvests at days 16,34,55,83, 143 and 225 were performed and pools of plant available DON and DIN were measured using 2M KCl extractions. At day 225 the microbial biomass N pool was also

  1. Spatial patterns of atmospheric deposition of nitrogen and sulfur using ion-exchange resin collectors in Rocky Mountain National Park, USA

    NASA Astrophysics Data System (ADS)

    Clow, David W.; Roop, Heidi A.; Nanus, Leora; Fenn, Mark E.; Sexstone, Graham A.

    2015-01-01

    Lakes and streams in Class 1 wilderness areas in the western United States (U.S.) are at risk from atmospheric deposition of nitrogen (N) and sulfur (S), and protection of these resources is mandated under the Federal Clean Air Act and amendments. Assessment of critical loads, which are the maximum exposure to pollution an area can receive without adverse effects on sensitive ecosystems, requires accurate deposition estimates. However, deposition is difficult and expensive to measure in high-elevation wilderness, and spatial patterns in N and S deposition in these areas remain poorly quantified. In this study, ion-exchange resin (IER) collectors were used to measure dissolved inorganic N (DIN) and S deposition during June 2006-September 2007 at approximately 20 alpine/subalpine sites spanning the Continental Divide in Rocky Mountain National Park. Results indicated good agreement between deposition estimated from IER collectors and commonly used wet + dry methods during summer, but poor agreement during winter. Snowpack sampling was found to be a more accurate way of quantifying DIN and S deposition during winter. Summer DIN deposition was significantly greater on the east side of the park than on the west side (25-50%; p ≤ 0.03), consistent with transport of pollutants to the park from urban and agricultural areas to the east. Sources of atmospheric nitrate (NO3-) were examined using N isotopes. The average δ15N of NO3- from IER collectors was 3.5‰ higher during winter than during summer (p < 0.001), indicating a seasonal shift in the relative importance of regional NOx sources, such as coal combustion and vehicular sources of atmospheric NO3-. There were no significant differences in δ15N of NO3- between east and west sides of the park during summer or winter (p = 0.83), indicating that the two areas may have similar sources of atmospheric NO3-. Results from this study indicate that a combination of IER collectors and snowpack sampling can be used to

  2. Solar cell modules for plasma interaction evaluation

    NASA Technical Reports Server (NTRS)

    1981-01-01

    A plasma interaction analysis in support of the solar electric propulsion subsystem examined the effects of a large high voltage solar array interacting with an ion thruster produced plasma. Two solar array test modules consisting of 36 large area wraparound contact solar cells welded to a flexible Kapton integrated circuit substrate were abricated. The modules contained certain features of the effects of insulation, din-holes, and bonding of the cell to the substrate and a ground plane. The possibility of a significant power loss occurring due to the collection of charged particles on the solar array interconnects was the focus of the research.

  3. Long term changes in the ecosystem in the northern South China Sea during 1976-2004

    NASA Astrophysics Data System (ADS)

    Ning, X.; Lin, C.; Hao, Q.; Liu, C.; Le, F.; Shi, J.

    2009-10-01

    Physical and chemical oceanographic data were obtained by seasonal monitoring along a transect (Transect N) in the northern South China Sea (nSCS) during 1976-2004. Fluctuations of DIN (dissolved inorganic nitrogen), seawater temperature (SST and Tav - average temperature of the water column), N:P ratio and salinity (Sav and S200 - salinity at the 200 m layer) exhibited an increasing trend, while those of T200, DO, P, Si, Si:N and SSS exhibited a decreasing trend. The annual rates of change in DIN, DO, T and S revealed pronounced changes, and the climate trend coefficients, which was defined as the correlation coefficient between the time series of an environmental parameter and the nature number (namely 1,2,3,......n), were 0.38 to 0.89 and significant (p≤0.01 to 0.05). Our results also showed that the ecosystem has obviously been influenced by the positive trends of both SST and DIN, and negative trends of both DO and P. For example, before 1997, DIN concentrations in the upper layer were very low and N:P ratios were less than half of the Redfield ratio of 16, indicating potential N limitation. However after 1997, all Si:P ratios were >22 and the Nav:Pav was close to the Redfield ratio, indicating potential P limitation, and therefore N limitation has been reduced after 1997. Ecological investigation shows that there have been some obvious responses of the ecosystems to the long-term environmental changes in the nSCS. Chlorophyll-a concentration, primary production, phytoplankton abundance, benthic biomass, cephalopod catch and demersal trawl catch have increased. But phosphorus depletion in upper layer may be related to the shift in the dominant species from diatoms to dinoflagellates and cyanophytes. The ecosystem response was induced by not only anthropogenic activities, but also global climate change, e.g. ENSO. The effects of climate change on the nSCS were mainly through changes in the monsoon winds, and physical-biological oceanography coupling processes

  4. Hydro-climatological non-stationarity shifts patterns of nutrient delivery to an estuarine system

    NASA Astrophysics Data System (ADS)

    Ruibal-Conti, A. L.; Summers, R.; Weaver, D.; Hipsey, M. R.

    2013-08-01

    The influence of hydro-climatological variability on catchment nutrient export was assessed by a retrospective analysis of rainfall, discharge, and total and dissolved nutrient loads for three sub-basins (Serpentine, Murray and Harvey) of the Peel-Harvey catchment, Western Australia. Both, temporal trends and their variability for different hydrological conditions (dry, normal or wet years) were analyzed from 1984 to 2011. Rainfall declined below median values for the study period over the last two decades and runoff decreased significantly in two of the three main rivers. Since Nitrogen (N) and Phosphorus (P) loads were strongly correlated with river discharge, nutrient exports decreased. However, when nutrient loads were flow-adjusted, increases in Total P (TP) and Total N (TN) were observed in the Serpentine and Murray rivers respectively, suggesting new sources of TP and TN and that the flow-export relationship is non-stationary. Dissolved Inorganic Phosphorus (DIP), showed a decreasing tendency in the last decade; but the trend in DIN loads is not clear and it appears to show a decreasing trend until 2004 and an increasing trend from 2004, accompanied with large inter-annual variability. The analysis of TP, TN, DIP and DIN in relation to dry and wet years, indicated that there is a significantly higher load in wet years for all three rivers, except for DIP in the Murray sub-catchment, explained by a higher proportion of soils with a higher Phosphorus Retention Index (PRI). Hydrological conditions, specific sub-catchment characteristics (e.g. soil type) and chemical properties of the nutrients altered the degree of nutrient partitioning (defined as dissolved inorganic to total nutrient concentration). For example, DIP increased to more than 50% of TP in wet years in Harvey and Serpentine but not in the Murray sub-catchment due to a higher PRI, while DIN behaved more randomly and did not show a link to discharge or the catchment soil type. We also found a mild

  5. Geochemical Rate/RNA Integration Study (GRIST): A Pilot Field Experiment for Inter-Calibration of Biogeochemistry and Nucleic Acid Measurements Final Report

    SciTech Connect

    Bronk, Deborah

    2007-01-08

    The Geochemical Rate/RNA Integration Study (GRIST) project sought to correlate biogeochemical flux rates with measurements of gene expression and mRNA abundance to demonstrate the application of molecular approaches to estimate the presence and magnitude of a suite of biogeochemical processes. The study was headed by Lee Kerkhoff of Rutgers University. In this component of the GRIST study, we characterized ambient nutrient concentrations and measured uptake rates for dissolved inorganic nitrogen (DIN, ammonium, nitrate and nitrite) and dissolved organic nitrogen (urea and dissolved free amino acids) during two diel studies at the Long-Term Ecosystem Observatory (LEO-15) on the New Jersey continental shelf.

  6. Seasonal baseline of nutrients and stable isotopes in a saline lake of Argentina: biogeochemical processes and river runoff effects.

    PubMed

    Kopprio, Germán A; Kattner, Gerhard; Freije, R Hugo; de Paggi, Susana José; Lara, Rubén J

    2014-05-01

    The seasonal variability of inorganic and organic nutrients and stable isotopes and their relations with plankton and environmental conditions were monitored in Lake Chasicó. Principal component analysis evidenced the strong influence of the river runoff on several biogeochemical variables. Silicate concentrations were controlled by diatom biomass and river discharge. Higher values of nitrate and soluble reactive phosphorus (SRP) indicated agricultural uses in the river basin. Elevated pH values (∼ 9) inhibiting nitrification in the lake explained partially the dominance of ammonium: ∼ 83 % of dissolved inorganic nitrogen (DIN). The low DIN/SRP ratio inferred nitrogen limitation, although the hypotheses of iron and CO2 limitation are relevant in alkaline lakes. Particulate organic matter (POM) and dissolved organic matter (DOM) were mainly of autochthonous origin. The main allochthonous input was imported by the river as POM owning to the arid conditions. Dissolved organic carbon was likely top-down regulated by the bacterioplankton grazer Brachionus plicatilis. The δ(13)C signature was a good indicator of primary production and its values were influenced probably by CO2 limitation. The δ(15)N did not evidence nitrogen fixation and suggested the effects of anthropogenic activities. The preservation of a good water quality in the lake is crucial for resource management.

  7. Acclimation conditions modify physiological response of the diatom Thalassiosira pseudonana to elevated CO2 concentrations in a nitrate-limited chemostat.

    PubMed

    Hennon, Gwenn M M; Quay, Paul; Morales, Rhonda L; Swanson, Lyndsey M; Virginia Armbrust, E

    2014-04-01

    Diatoms are responsible for a large proportion of global carbon fixation, with the possibility that they may fix more carbon under future levels of high CO2 . To determine how increased CO2 concentrations impact the physiology of the diatom Thalassiosira pseudonana Hasle et Heimdal, nitrate-limited chemostats were used to acclimate cells to a recent past (333 ± 6 μatm) and two projected future concentrations (476 ± 18 μatm, 816 ± 35 μatm) of CO2 . Samples were harvested under steady-state growth conditions after either an abrupt (15-16 generations) or a longer acclimation process (33-57 generations) to increased CO2 concentrations. The use of un-bubbled chemostat cultures allowed us to calculate the uptake ratio of dissolved inorganic carbon relative to dissolved inorganic nitrogen (DIC:DIN), which was strongly correlated with fCO2 in the shorter acclimations but not in the longer acclimations. Both CO2 treatment and acclimation time significantly affected the DIC:DIN uptake ratio. Chlorophyll a per cell decreased under elevated CO2 and the rates of photosynthesis and respiration decreased significantly under higher levels of CO2 . These results suggest that T. pseudonana shifts carbon and energy fluxes in response to high CO2 and that acclimation time has a strong effect on the physiological response.

  8. A Mechanistic Study of Plant and Microbial Controls over R* for Nitrogen in an Annual Grassland

    PubMed Central

    Levine, Jonathan M.; HilleRisLambers, Janneke

    2014-01-01

    Differences in species' abilities to capture resources can drive competitive hierarchies, successional dynamics, community diversity, and invasions. To investigate mechanisms of resource competition within a nitrogen (N) limited California grassland community, we established a manipulative experiment using an R* framework. R* theory holds that better competitors within a N limited community should better depress available N in monoculture plots and obtain higher abundance in mixture plots. We asked whether (1) plant uptake or (2) plant species influences on microbial dynamics were the primary drivers of available soil N levels in this system where N structures plant communities. To disentangle the relative roles of plant uptake and microbially-mediated processes in resource competition, we quantified soil N dynamics as well as N pools in plant and microbial biomass in monoculture plots of 11 native or exotic annual grassland plants over one growing season. We found a negative correlation between plant N content and soil dissolved inorganic nitrogen (DIN, our measure of R*), suggesting that plant uptake drives R*. In contrast, we found no relationship between microbial biomass N or potential net N mineralization and DIN. We conclude that while plant-microbial interactions may have altered the overall quantity of N that plants take up, the relationship between species' abundance and available N in monoculture was largely driven by plant N uptake in this first year of growth. PMID:25170943

  9. Response of northern San Francisco Bay to riverine inputs of dissolved inorganic carbon, silicon, nitrogen and phosphorus

    USGS Publications Warehouse

    Schemel, Laurence E.; Harmon, Dana D.; Eager, Stephen W.; Peterson, David H.; Kennedy, Victor S.

    1984-01-01

    Estuarine processes can be effective in modifying (filtering) distributions of dissolved inorganic forms of carbon (DIC), silicon (DIS), nitrogen (DIN), and phosphorus (DIP) in northern San Francisco Bay. During winter, high inflow from the Sacramento-San Joaquin river system supplied these nutrients to the estuary at rates that exceeded potential rates of estuarine supply and removal processes. During spring and summer, when inflow rates were lower, the estuary was an effective “filter” of the river inflow “signal” because rates of estuarine processes were high relative to river and other supply rates. At lower inflow rates, the river apparently influenced estuarine hydrodynamic features that controlled rates of phytoplankton nutrient removal. Largest biological removal effects were localized in San Pablo Bay during spring and Suisun Bay during summer, and they were generally more pronounced in shallow water areas of the bays. In San Pablo Bay, effects of biological removal appeared soon after river inflow decreased from high winter rates, but persisted for only a short time. During the following summer months, DIN and DIP distributions in San Pablo Bay indicated that estuarine sources contributed to higher concentrations of these nutrients.

  10. Selective Gating of Neuronal Activity by Intrinsic Properties in Distinct Motor Rhythms.

    PubMed

    Li, Wen-Chang

    2015-07-01

    Many neural circuits show fast reconfiguration following altered sensory or modulatory inputs to generate stereotyped outputs. In the motor circuit of Xenopus tadpoles, I study how certain voltage-dependent ionic currents affect firing thresholds and contribute to circuit reconfiguration to generate two distinct motor patterns, swimming and struggling. Firing thresholds of excitatory interneurons [i.e., descending interneurons (dINs)] in the swimming central pattern generator are raised by depolarization due to the inactivation of Na(+) currents. In contrast, the thresholds of other types of neurons active in swimming or struggling are raised by hyperpolarization from the activation of fast transient K(+) currents. The firing thresholds are then compared with the excitatory synaptic drives, which are revealed by blocking action potentials intracellularly using QX314 during swimming and struggling. During swimming, transient K(+) currents lower neuronal excitability and gate out neurons with weak excitation, whereas their inactivation by strong excitation in other neurons increases excitability and enables fast synaptic potentials to drive reliable firing. During struggling, continuous sensory inputs lead to high levels of network excitation. This allows the inactivation of Na(+) currents and suppression of dIN activity while inactivating transient K(+) currents, recruiting neurons that are not active in swimming. Therefore, differential expression of these currents between neuron types can explain why synaptic strength does not predict firing reliability/intensity during swimming and struggling. These data show that intrinsic properties can override fast synaptic potentials, mediate circuit reconfiguration, and contribute to motor-pattern switching.

  11. Adaptive mutation and amplification in Escherichia coli: two pathways of genome adaptation under stress.

    PubMed

    Hersh, Megan N; Ponder, Rebecca G; Hastings, P J; Rosenberg, Susan M

    2004-06-01

    The neo-Darwinists suggested that evolution is constant and gradual, and thus that genetic changes that drive evolution should be too. However, more recent understanding of phenomena called adaptive mutation in microbes indicates that mutation rates can be elevated in response to stress, producing beneficial and other mutations. We review evidence that, in Escherichia coli, two separate mechanisms of stress-induced genetic change occur that revert a lac frameshift allele allowing growth on lactose medium. First, compensatory frameshift ("point") mutations occur by a mechanism that includes DNA double-strand breaks and (we have suggested) their error-prone repair. Point mutation requires induction of the RpoS-dependent general stress response, and the SOS DNA damage response leading to upregulation of the error-prone DNA polymerase DinB (Pol IV), and occurs during a transient limitation of post-replicative mismatch repair activity. A second mechanism, adaptive amplification, entails amplification of the leaky lac allele to 20-50 tandem repeats. These provide sufficient beta-galactosidase activity for growth, thereby apparently deflecting cells from the point mutation pathway. Unlike point mutation, amplification neither occurs in hypermutating cells nor requires SOS or DinB, but like point mutation, amplification requires the RpoS-dependent stress response. Similar processes are being found in other bacterial systems and yeast. Stress-induced genetic changes may underlie much of microbial evolution, pathogenesis and antibiotic resistance, and also cancer formation, progression and drug resistance. PMID:15207867

  12. Experimental Behavior of Carbon Fiber Reinforced Isolators

    SciTech Connect

    Russo, Gaetano; Pauletta, Margherita; Cortesia, Andrea; Dal Bianco, Alberto

    2008-07-08

    This paper describes an investigation on the experimental behavior of innovative elastomeric isolators reinforced by carbon fiber fabrics. These fabrics are very much lighter than steel plates used in conventional isolators and able to transfer to the adjacent elastomer layers tangential stresses adequate to oppose the transversal deformation of rubber under vertical loads. The isolators are not bonded to the sub- and super-structure (elimination of the steel end-plates), hence their weight and cost are reduced. The experimental investigation is carried out on small-scale isolator prototypes reinforced by quadridirectional carbon fiber fabrics. The isolators are subjected to the following qualification tests prescribed by the Italian Code 'Ordinanza 3274' for steel reinforced isolators: 1) 'Static assessment of the compression stiffness'; 2) 'Static assessment of the shear modulus G'; 3) 'Dynamic assessment of the dynamic shear modulus G{sub din} and of the damping coefficient {xi}; 4) 'Assessment of the G{sub din}-{gamma} and {xi}-{gamma} diagrams by means of dynamic tests'; 5) 'Assessment of creep characteristics'; 6) 'Evaluation of the capacity of sustaining at least 10 cycles'. As a result of the tests, the isolators survived large shear strains, comparable to those expected for conventional isolators.

  13. Dissolved inorganic nitrogen composition, transformation, retention, and transport in naturally phosphate-rich and phosphate-poor tropical streams

    USGS Publications Warehouse

    Triska, F.J.; Pringle, C.M.; Zellweger, G.W.; Duff, J.H.; Avanzino, R.J.

    1993-01-01

    In Costa Rica, the Salto River is enriched by geothermal-based soluble reactive phosphorus (SRP), which raises the concentration up to 200 ??g/L whereas Pantano Creek, an unimpacted tributary, has an SRP concentration <10 ??g/L. Ammonium concentration in springs adjacent to the Salto and Pantano was typically greater than channel water (13 of 22 locations) whereas nitrate concentration was less (20 of 22 locations). Ground waters were typically high in ammonium relative to nitrate whereas channel waters were high in nitrate relative to ammonium. Sediment slurry studies indicated nitrification potential in two sediment types, firm clay (3.34 ??g N.cm-3.d-1) and uncompacted organic-rich sediment (1.76 ??g N.cm-3.d-1). Ammonium and nitrate amendments to each stream separately resulted in nitrate concentrations in excess of that expected after correlation for dilution using a conservative tracer. SRP concentration was not affected by DIN amendment to either stream. SRP concentration in the Pantano appeared to be regulated by abiotic sediment exchange reactions. DIN composition and concentration were regulated by a combination of biotic and abiotic processes. -from Authors

  14. Ecologically based targets for bioavailable (reactive) nitrogen discharge from the drainage basins of the Wet Tropics region, Great Barrier Reef.

    PubMed

    Wooldridge, Scott A; Brodie, Jon E; Kroon, Frederieke J; Turner, Ryan D R

    2015-08-15

    A modelling framework is developed for the Wet Tropics region of the Great Barrier Reef that links a quantitative river discharge parameter (viz. dissolved inorganic nitrogen concentration, DIN) with an eutrophication indicator within the marine environment (viz. chlorophyll-a concentration, chl-a). The model predicts catchment-specific levels of reduction (%) in end-of-river DIN concentrations (as a proxy for total potentially reactive nitrogen, PRN) needed to ensure compliance with chl-a 'trigger' guidelines for the ecologically distinct, but PRN-related issues of crown-of-thorns starfish (COTS) outbreaks, reef biodiversity loss, and thermal bleaching sensitivity. The results indicate that even for river basins dominated by agricultural land uses, quite modest reductions in end-of-river PRN concentrations (∼20-40%) may assist in mitigating the risk of primary COTS outbreaks from the mid-shelf reefs of the Wet Tropics. However, more significant reductions (∼60-80%) are required to halt and reverse declines in reef biodiversity, and loss of thermal bleaching resistance.

  15. Controlling factors of seasonal variation in the nitrogen isotope ratio of nitrate in a eutrophic coastal environment

    NASA Astrophysics Data System (ADS)

    Sugimoto, Ryo; Kasai, Akihide; Miyajima, Toshihiro; Fujita, Kouichi

    2009-11-01

    Seasonal changes in the nitrogen stable isotope ratio of NO 3-(δNNO15) were investigated in a temperate eutrophic coastal embayment in Japan. Wide variation of δNNO15 from -10.4 to 9.3‰ was found along with changes in temperature, dissolved oxygen concentrations, and the composition of the dissolved inorganic nitrogen (DIN) pool. Throughout the year, δNNO15 showed positive exponential and linear relationships with NO 3- concentrations and fractions, respectively. The minima of δNNO15 were observed in spring and autumn when the NO 3- fraction in DIN was small, while the maximum was in summer when the NO 3- fraction was large. These results indicate that nitrification was the dominant process that determined δNNO15 variation. The δNNO15 minima in spring and autumn suggested that hydrographic properties, such as low water temperature and short residence time of the water, suppressed the nitrifying bacterial activity in these seasons. An apparent nitrogen isotope discrimination ( ɛnit) by nitrification was estimated as -15 to -25‰, which is similar to or slightly higher than previous laboratory estimates of marine nitrifiers. Furthermore, isotope results at the bay center over a year suggest that most of the NO 3- was regenerated by in situ nitrification in the water-column. This implies that large amounts of regenerated nitrogen would lead the eutrophication in Ise Bay.

  16. Ecologically based targets for bioavailable (reactive) nitrogen discharge from the drainage basins of the Wet Tropics region, Great Barrier Reef.

    PubMed

    Wooldridge, Scott A; Brodie, Jon E; Kroon, Frederieke J; Turner, Ryan D R

    2015-08-15

    A modelling framework is developed for the Wet Tropics region of the Great Barrier Reef that links a quantitative river discharge parameter (viz. dissolved inorganic nitrogen concentration, DIN) with an eutrophication indicator within the marine environment (viz. chlorophyll-a concentration, chl-a). The model predicts catchment-specific levels of reduction (%) in end-of-river DIN concentrations (as a proxy for total potentially reactive nitrogen, PRN) needed to ensure compliance with chl-a 'trigger' guidelines for the ecologically distinct, but PRN-related issues of crown-of-thorns starfish (COTS) outbreaks, reef biodiversity loss, and thermal bleaching sensitivity. The results indicate that even for river basins dominated by agricultural land uses, quite modest reductions in end-of-river PRN concentrations (∼20-40%) may assist in mitigating the risk of primary COTS outbreaks from the mid-shelf reefs of the Wet Tropics. However, more significant reductions (∼60-80%) are required to halt and reverse declines in reef biodiversity, and loss of thermal bleaching resistance. PMID:26072049

  17. Relationship between environmental factors and plankton in the Bayuquan Port, Liaodong Bay, China: a five-year study

    NASA Astrophysics Data System (ADS)

    Song, Lun; Yang, Guojun; Wang, Nianbin; Lu, Xiaoqian

    2016-07-01

    To understand the relationship between the plankton community and environmental factors and water quality in the Bayuquan Port of Liaodong Bay, China, and investigations were carried out during six different periods (April 2009, April 2010, October 2011, April 2012, October 2012, and April 2013). This area was characterized by high levels of nutrient and suspended solids (SPS) during survey periods, and eutrophication led to the occurrence of red tides in April and October 2012 and April 2013. Our analyses revealed that the plankton communities of Bayuquan Port lacked stability and were affected seriously by external disturbance (e.g., oceanographic engineering and river runoff). Our data indicate that oil, dissolved inorganic nitrogen (DIN), SPS, and chlorophyll a (Chl- a) were key factors that regulated the phytoplankton and zooplankton communities. The partial redundancy analysis (partial RDA) suggested that oil and SPS were the most important environmental variables affecting the phytoplankton community in April 2010 and 2012, whereas DIN concentration played a governing role in zooplankton dynamics. Oil and Chl- a concentrations affected significantly the zooplankton community in October 2012. Therefore, the plankton communities could reflect both dynamic changes in coastal environmental factors and the ongoing eutrophication process caused by anthropogenic activities in this area.

  18. Environmental factors affecting distribution and abundance of bacteria, fungi and protozoa in subsurface sediments of the Upper Atlantic Coastal Plain, USA

    SciTech Connect

    Levine, S.N.; Ghiorse, W.C.

    1990-01-01

    Exploratory statistical analyses of microbiological, hydrological and geochemical data for samples from four boreholes drilled into Upper Atlantic Coastal Plain sediments near the Savannah River Site, SC, showed highly significant correlations between bacterial abundance (AODC and CFU) and hydraulic conductivity (K). Sediment texture variables (% sand (S), % silt, % clay (C), and S/C) were strongly interrelated with K and, therefore, also correlated with bacterial abundance. AODC did not correlate with the concentrations of dissolved inorganic nitrogen (DIN) or dissolved organic carbon (DOC) in pore water. CFU also did not correlate with DIN, but a negative relationship was found between the CFU and DOC for sandy sediments, suggesting that microbial activity may control pore water DOC concentration. In some, but not all boreholes, AODC and CFU correlated negatively with pore water concentrations of metals and positively with pH. Protozoan abundance correlated strongly with AODC and CFU in the two boreholes closest to the recharge areas for their major aquifers. It also correlated with sediment texture variables, but not with K. Fungal abundance did not correlate with the abundance of other microbial types when data from individual boreholes were considered; however it did correlate with both bacterial and protozoan abundance when data from all four boreholes were combined. There was no relationship between fungal abundance and either K or sediment texture.

  19. Environmental factors affecting distribution and abundance of bacteria, fungi and protozoa in subsurface sediments of the Upper Atlantic Coastal Plain, USA

    SciTech Connect

    Levine, S.N.; Ghiorse, W.C.

    1990-12-31

    Exploratory statistical analyses of microbiological, hydrological and geochemical data for samples from four boreholes drilled into Upper Atlantic Coastal Plain sediments near the Savannah River Site, SC, showed highly significant correlations between bacterial abundance (AODC and CFU) and hydraulic conductivity (K). Sediment texture variables (% sand (S), % silt, % clay (C), and S/C) were strongly interrelated with K and, therefore, also correlated with bacterial abundance. AODC did not correlate with the concentrations of dissolved inorganic nitrogen (DIN) or dissolved organic carbon (DOC) in pore water. CFU also did not correlate with DIN, but a negative relationship was found between the CFU and DOC for sandy sediments, suggesting that microbial activity may control pore water DOC concentration. In some, but not all boreholes, AODC and CFU correlated negatively with pore water concentrations of metals and positively with pH. Protozoan abundance correlated strongly with AODC and CFU in the two boreholes closest to the recharge areas for their major aquifers. It also correlated with sediment texture variables, but not with K. Fungal abundance did not correlate with the abundance of other microbial types when data from individual boreholes were considered; however it did correlate with both bacterial and protozoan abundance when data from all four boreholes were combined. There was no relationship between fungal abundance and either K or sediment texture.

  20. Rapid authentication of coffee blends and quantification of 16-O-methylcafestol in roasted coffee beans by nuclear magnetic resonance.

    PubMed

    Schievano, Elisabetta; Finotello, Claudia; De Angelis, Elisabetta; Mammi, Stefano; Navarini, Luciano

    2014-12-24

    Roasted coffee is subject to commercial frauds, because the high-quality Coffea arabica species, described as "100% Arabica" or "Highland coffee", is often mixed with the less expensive Coffea canephora var. Robusta. The quantification of 16-O-methylcafestol (16-OMC) is useful to monitor the authenticity of the products as well as the Robusta content in blends. The German standard method DIN 10779 is used in the determination of 16-OMC in roasted coffee beans to detect C. canephora in blends, but it is laborious and time-consuming. Here, we introduce a new method that provides a quantitative determination of esterified 16-OMC directly in coffee extracts by means of high-resolution proton nuclear magnetic resonance spectroscopy. Limit of detection and limit of quantitation were 5 and 20 mg/kg, respectively, which are adequate to detect the presence of Robusta at percentages lower than 0.9%. The proposed method is much faster, more sensitive, and much more reproducible than the DIN standard method.

  1. Contribution of Outer-shelf Deep Water to the nutrient inventories in the euphotic zone of Changjiang River plume during summer

    NASA Astrophysics Data System (ADS)

    Chen, Jianfang

    2016-04-01

    Nutrient supply to the euphotic zone of high productivity area in the Changjiang Estuary,East China Sea is crucial in understanding algal bloom and hypoxia in this area. Previous studies suggested that Changjiang Diluted Water (CDW) and Outer-shelf Deep Water (ODW) are two main sources for nutrient supply while quantitative estimation of each nutrient species to the euphotic zone remains unknown. Based on a field survey and end-member mixing model, the nutrient inventories of ODW, and its contribution to the model-predicted nutrient inventory in the euphotic zone of Changjiang River plume-impacted area were assessed. Upwelling of ODW was identified, indicating that it significantly contributed to nutrient inventories in the upper layer. The nutrient inventory estimation suggested that the area-integrated nutrient inventories of ODW were higher than that of CDW in the euphotic zone of plume-impacted area. As inferred from the mixing model, the contributions of ODW to DIN and silicate inventories in the euphotic zone were 18.2% and 28.1%, respectively, much lower than that of CDW. However, 37.6% and 39.1% of the phosphate inventory were from ODW and CDW, respectively, indicating that ODW phosphate contribution was comparable with that of CDW in the euphotic zone, while DIN and silicate brought by ODW were less

  2. [Variation of nutrient concentrations at the inshore coastal area of northern Jiangsu province and the occurrence of green tide caused by Enteromorpha prolifera].

    PubMed

    Gao, Song; Shi, Xiao-Yong; Wang, Ting

    2012-07-01

    Based on the investigation of the inshore coastal area of northern Jiangsu province with occurrence of green tide caused by Enteromorpha prolifera, which was performed in five voyages during March to June 2010, the variation of nutrient concentrations and its distribution characteristics were studied in this paper. The results showed that the concentrations of nutrients were relatively high in this region due to the terrestrial runoff and northern Jiangsu coastal current, which contributed to the outbreak of green tide. The highest concentrations of dissolved inorganic N (DIN), PO4(3-)-P and SiO3(2-)-Si were 23.04, 0. 55 and 15.85 micromol x L(-1), respectively. In spring, due to the strong life activities of plankton and the intake of nutrients by green tide, the concentrations of NO(3-)-N, PO4(3-)-P, SiO3(2-)-Si and DIN all showed a tendency of decreasing from the first to the fifth voyage. Besides, the closer the N/P ratios in water and in the body of plankton, the faster the plankton grows. The N/P ratios measured in the fourth and fifth voyages were relatively favorable for the growth of Enteromorpha prolifera. The distribution characteristics of nutrients had a tendency of decreasing from inshore to offshore in all voyages.

  3. [The suitability of commercial bioindicators with spores of B. stearothermophilus for the testing of formaldehyde gas sterilizers].

    PubMed

    Mecke, P; Christiansen, B; Pirk, A

    1991-09-01

    Commercially available biological indicators with spores of B. stearothermophilus were investigated by the Hygiene-Institutes of Kiel and Lubeck. The objective was to find out if those indicators to which sheep blood was added subsequently correspond to the formaldehyde resistance required by. DIN 58948, part 14 (DIN 58948, part 13). Both working groups determined unanimously that the indicators of one producer showed a resistance too low compared to the remaining biological indicators showing a much higher resistance than required. Even biological indicators manufactured strictly in accordance to the testing standard were more resistant than demanded. This also corresponded to the commercially available untreated spores. On the other hand, practice showed that the biological indicators investigated within this study can be easily killed by formaldehyde sterilizers if they respond to the technical standard. In order to realize the testing of these sterilizers with indicators of a generally accepted resistance we propose either to demand for an equivalently higher formaldehyde resistance or to set up a killing period for the spore resistance from 150 to 240 min until experimentally important data are available. Concerning the blood containing indicators the results of both working groups differed considerably within the limits of formaldehyde efficiency whereas this was not the case with untested commercially available spores. As the addition of thinned blood did not cause an increase in resistance we recommend, in the interest of standardized investigative conditions, not to use it. PMID:1953931

  4. Eliminating "ductal carcinoma in situ" and "lobular carcinoma in situ" (DCIS and LCIS) terminology in clinical breast practice: The cognitive psychology point of view.

    PubMed

    Pravettoni, Gabriella; Yoder, Whitney R; Riva, Silvia; Mazzocco, Ketti; Arnaboldi, Paola; Galimberti, Viviana

    2016-02-01

    There is evidence from the literature that the terms "ductal carcinoma in situ" and "lobular carcinoma in situ" (DCIS and LCIS) should be eliminated in clinical breast cancer practice and replaced with the new "ductal intraepithelial neoplasia" (DIN) and "lobular intraepithelial neoplasia" (LIN) terminology. The main purpose of the present article is to expand on this argument from a cognitive psychology perspective and offer suggestions for further research, emphasizing how the elimination of the term "carcinoma" in "in situ" breast cancer diagnoses has the potential to reduce both patient and health care professional confusion and misperceptions that are often associated with the DCIS and LCIS diagnoses, as well as limit the adverse psychological effects of women receiving a DCIS or LCIS diagnosis. We comment on the recent peer-reviewed literature on the clinical implications and psychological consequences for breast cancer patients receiving a DCIS or LCIS diagnosis and we use a cognitive perspective to offer new insight into the benefits of embracing the new DIN and LIN terminology. Using cognitive psychology and cognitive science in general, as a foundation, further research is advocated in order to yield data in support of changing the terminology and therefore, offer a chance to significantly improve the lives and psychological sequelae of women facing such a diagnosis. Typology: Controversies/Short Commentary. PMID:26614547

  5. Derivation of mean impedance curves as a basis for mechanical models of the human hand-arm system.

    PubMed

    Kinne, J; Melzig-Thiel, R

    1996-02-01

    he use of mechanical models of the human hand-arm system in test stands can substitute man in several activities with exposition to vibration. An example is prototype testing of percussion drills. Modelling should be based on ascertained mean impedance curves of the hand-arm system. The method chosen was deriving curves for the three directions by using DIN and ISO standards (such as DIN 45677) as well as comprehensive literature and results of own measurements. At present it can be stated that: Literature is scarce especially with regard to the test conditions. Thus the causes of--sometimes largely--varying test results are difficult or impossible to be traced. There is conformity with the standards in principle. However, deviations exist for the frequency range determining the aw-value so that the application of mean standard curves for modelling the hand-arm system can lead to mistakes compared to test persons. Literature clearly shows an influence of hand grip force on the impedance curves. Standardisation seems not to consider this influence sufficiently. Mechanical models should take it into account. For feed force, there is no evidence for such a clear influence on the impedance curves.

  6. Water quality and coral bleaching thresholds: formalising the linkage for the inshore reefs of the Great Barrier Reef, Australia.

    PubMed

    Wooldridge, Scott A

    2009-05-01

    The threats of wide-scale coral bleaching and reef demise associated with anthropogenic climate change are widely known. Here, the additional role of poor water quality in lowering the thermal tolerance (i.e. bleaching 'resistance') of symbiotic reef corals is considered. In particular, a quantitative linkage is established between terrestrially-sourced dissolved inorganic nitrogen (DIN) loading and the upper thermal bleaching thresholds of inshore reefs on the Great Barrier Reef, Australia. Significantly, this biophysical linkage provides concrete evidence for the oft-expressed belief that improved coral reef management will increase the regional-scale survival prospects of corals reefs to global climate change. Indeed, for inshore reef areas with a high runoff exposure risk, it is shown that the potential benefit of this 'local' management imperative is equivalent to approximately 2.0-2.5 degrees C in relation to the upper thermal bleaching limit; though in this case, a potentially cost-prohibitive reduction in end-of-river DIN of >50-80% would be required. An integrated socio-economic modelling framework is outlined that will assist future efforts to understand (optimise) the alternate tradeoffs that the water quality/coral bleaching linkage presents.

  7. Crustal deformation associated with an M8.1 earthquake in the Solomon Islands, detected by ALOS/PALSAR

    NASA Astrophysics Data System (ADS)

    Miyagi, Yousuke; Ozawa, Taku; Shimada, Masanobu

    2009-10-01

    On April 1, 2007 (UTC), a large Mw 8.1 interplate earthquake struck the Solomon Islands subduction zone where complicated tectonics result from the subduction of four plates. Extensive ground movements and a large tsunami occurred in the epicentral area causing severe damage over a wide area. Using ALOS/PALSAR data and the DInSAR technique, we detected crustal deformation exceeding 2 m in islands close to the epicenter. A slip distribution of the inferred seismic fault was estimated using geodetic information derived from DInSAR processing and field investigations. The result indicates large slip areas around the hypocenter and the centroid. It is possible that the largest slip area is related to subduction of the plate boundary between the Woodlark and Australian plates. A small slip area between those large slip areas may indicate weak coupling due to thermal activity related to volcanic activity on Simbo Island. The 2007 earthquake struck an area where large earthquake has not occurred since 1970. Most of this seismic gap was filled by the 2007 events, however a small seismic gap still remains in the southeastern region of the 2007 earthquake.

  8. Dispersión de velocidades en cúmulos de galaxias

    NASA Astrophysics Data System (ADS)

    Muriel, H.; García Lambas, D.; Quintana, H.; Infante, L.

    Se ha estudiado la dinámica de galaxias en cúmulos en base a una muestra de aproximadamente 4000 galaxias con estimas de velocidad radial pertenecientes a 40 cúmulos. Se desarrolló un algoritmo para identificar sub-estructuras del tipo ``grupos de galaxias". Una vez eliminada este tipo de sub-estructura se computaron los perfiles radiales de dispersión de velocidades (VDP) para los 40 cúmulos de galaxias. Dada las características de la muestra, fue posible estimar el VDP hasta grandes distancias del centro del cúmulo llegando en algunos casos hasta 7 Mpc-1. Los resultados indican que el 65% de los cúmulos presentan un VDP plano a grandes radios consistente con el modelo isotermo. Estos resultados son discutidos en el marco de las recientes controversias suscitadas respecto de la dinámica de los cúmulos vía los perfiles de temperaturas de cúmulos derivados de la emisión en rayos-X.

  9. ACID EVAPORATION OF ULTIMA GOLD TM AB LIQUID SCINTILLATION COCKTAIL RESIDUE

    SciTech Connect

    Kyser, E.; Fondeur, F.; Crump, S.

    2011-12-21

    Prior analyses of samples from the F/H Lab solutions showed the presence of diisopropylnapthalene (DIN), a major component of Ultima Gold{trademark} AB liquid scintillation cocktail (LSC). These solutions are processed through H-Canyon Tank 10.5 and ultimately through the 17.8E evaporator. Similar solutions originated in SRNL streams sent to the same H Canyon tanks. This study examined whether the presence of these organics poses a process-significant hazard for the evaporator. Evaporation and calorimetry testing of surrogate samples containing 2000 ppm of Ultima Gold{trademark} AB LSC in 8 M nitric acid have been completed. These experiments showed that although reactions between nitric acid and the organic components do occur, they do not appear to pose a significant hazard for runaway reactions or generation of energetic compounds in canyon evaporators. The amount of off-gas generated was relatively modest and appeared to be well within the venting capacity of the H-Canyon evaporators. A significant fraction of the organic components likely survives the evaporation process primarily as non-volatile components that are not expected to represent any new process concerns during downstream operations such as neutralization. Laboratory Waste solutions containing minor amounts of DIN can be safely received, stored, transferred, and processed through the canyon waste evaporator.

  10. [Nutrient distribution and its relationship with occurrence of red tide in coastal area of East China Sea].

    PubMed

    Han, Xiurong; Wang, Xiulin; Sun, Xia; Shi, Xiaoyong; Zhu, Chenjian; Zhang, Chuansong; Lu, Rong

    2003-07-01

    Nutrient (NO3(-)-N, PO4(3-)-P, Sio3(2-)-Si, NH4(+)-N, etc.) concentrations in coastal area of East China Sea were measured during April 25 to May 2, 2002, and the relationship between the spatial distribution of the nutrients and the red tide occurrence in the studied area was analyzed. The results showed that compared to the 1st class seawater quality of the national standard, the concentrations of dissolved inorganic nitrogen (DIN) and PO4(-)-P were 46% and 60% higher, respectively, showing that the studied area, especially the Changjiang River estuary and the Hangzhou Bay, was at a disadvantage of eutrophication. Furthermore, the nutrient concentrations inshore were much higher than those offshore, and the isolines nearly paralleled with the coastline, meaning that the nutrient distributions were mainly influenced by terrestrial discharges. It also showed that the relatively high concentrations of nutrients, especially DIN and PO4(3-)-P, might result in the red-tide occurrence. However, the red tide did not occur in the area with the highest concentrations of the nutrients, further demonstrating that the eutrophication was not the unique environmental factor inducing red-tide occurrence.

  11. The dependence of the high temperature mechanical properties of austenitic stainless steels on implanted helium

    NASA Astrophysics Data System (ADS)

    Schroeder, Herbert; Batfalsky, Peter

    1983-07-01

    High temperature helium embrittlement effects on the creep properties of AISI 316 SS (solution annealed + aged) and DIN 1.4970 SS (solution annealed + cold worked + aged) have been investigated. The generation of helium due to (n. α) nuclear reactions in a fusion reactor environment has been simulated by homogeneous helium implantation at a cyclotron. The creep rupture tests with various applied tensile stresses have been carried out at 1023 K. (316 SS) and 1079 K (1.4970 SS). respectively, with four differently treatly sets of samples: (1) unimplanted controls; (2) after room temperature implantation of 100 appm He; (3) after implantation of 100 appm He at test temperature; (4) creep tested at high temperature during implantation ("in-beam") with implantation rates of 10-100 appm He/b. In contrast to the ductile behaviour with transgranular failure of the unimplanted controls, all He-implanted samples showed brittle, intergranular early failure. The embrittlement effect was enhanced for the "in-beam" tested samples. The difference between the different treated sets of samples can be related to different bubble microstructures investigated by TEM. In addition, a comparison to reactor data for the DIN 1.4970 SS is presented.

  12. Effect of active screen plasma nitriding pretreatment on wear behavior of TiN coating deposited by PACVD technique

    NASA Astrophysics Data System (ADS)

    Raoufi, M.; Mirdamadi, Sh.; Mahboubi, F.; Ahangarani, Sh.; Mahdipoor, M. S.; Elmkhah, H.

    2012-08-01

    Titanium based alloys are used extensively for improving wear properties of different parts due to their high hardness contents. Titanium nitride (TiN) is among these coatings which can be deposited on surface using various techniques such as CVD, PVD and PACVD. Their weak interface with substrate is one major drawback which can increase the total wear in spite of favorite wear behavior of TiN. Disc shaped samples from AISI H13 (DIN 1.2344) steel were prepared in this study. Single TiN coating was deposited on some of them while others have experienced a TiN deposition by active screen plasma nitriding (ASPN). Hardness at the surface and depth of samples was measured through Vickers micro hardness test which revealed 1810 Hv hardness as the maximum values for a dual-layered ASPN-TiN. Pin-on-disc wear test was done in order to study the wear mechanism. In this regard, the wear behavior of samples was investigated against pins from 100Cr6 (Din 1.3505) bearing steel and tungsten carbide-cobalt (WC-Co) steel. It was evidenced that the dual-layer ASPN-TiN coating has shown the least weight loss with the best wearing behavior because of its high hardness values, stable interface and acceptable resistance against peeling during wearing period.

  13. Computation and visualization of the MacAdam limits for any lightness, hue angle, and light source

    NASA Astrophysics Data System (ADS)

    Martínez-Verdú, Francisco; Perales, Esther; Chorro, Elisabet; de Fez, Dolores; Viqueira, Valentín; Gilabert, Eduardo

    2007-06-01

    We present a systematic algorithm capable of searching for optimal colors for any lightness L* (between 0 and 100), any illuminant (D65, F2, F7, F11, etc.), and any light source reported by CIE. Color solids are graphed in some color spaces (CIELAB, SVF, DIN99d, and CIECAM02) by horizontal (constant lightness) and transversal (constant hue angle) sections. Color solids plotted in DIN99d and CIECAM02 color spaces look more spherical or homogeneous than the ones plotted in CIELAB and SVF color spaces. Depending on the spectrum of the light source or illuminant, the shape of its color solid and its content (variety of distinguishable colors, with or without color correspondence) change drastically, particularly with sources whose spectrum is discontinuous and/or very peaked, with correlated color temperature lower than 5500 K. This could be used to propose an absolute colorimetric quality index for light sources comparing the volumes of their gamuts, in a uniform color space.

  14. Ernst Rüdin’s Unpublished 1922-1925 Study “Inheritance of Manic-Depressive Insanity”: Genetic Research Findings Subordinated to Eugenic Ideology

    PubMed Central

    Kösters, Gundula; Steinberg, Holger; Kirkby, Kenneth Clifford; Himmerich, Hubertus

    2015-01-01

    In the early 20th century, there were few therapeutic options for mental illness and asylum numbers were rising. This pessimistic outlook favoured the rise of the eugenics movement. Heredity was assumed to be the principal cause of mental illness. Politicians, scientists and clinicians in North America and Europe called for compulsory sterilisation of the mentally ill. Psychiatric genetic research aimed to prove a Mendelian mode of inheritance as a scientific justification for these measures. Ernst Rüdin’s seminal 1916 epidemiological study on inheritance of dementia praecox featured large, systematically ascertained samples and statistical analyses. Rüdin’s 1922–1925 study on the inheritance of “manic-depressive insanity” was completed in manuscript form, but never published. It failed to prove a pattern of Mendelian inheritance, counter to the tenets of eugenics of which Rüdin was a prominent proponent. It appears he withheld the study from publication, unable to reconcile this contradiction, thus subordinating his carefully derived scientific findings to his ideological preoccupations. Instead, Rüdin continued to promote prevention of assumed hereditary mental illnesses by prohibition of marriage or sterilisation and was influential in the introduction by the National Socialist regime of the 1933 “Law for the Prevention of Hereditarily Diseased Offspring” (Gesetz zur Verhütung erbkranken Nachwuchses). PMID:26544949

  15. Influence of fillers on NR/SBR blends containing ENR-organoclay nanocomposites: morphology and wear.

    PubMed

    Pal, Kaushik; Rajasekar, R; Pal, Samir Kumar; Kim, Jin Kuk; Das, Chapal Kumar

    2010-05-01

    In this study the Epoxidized natural rubber (ENR) and Organoclay (Cloisite 20A) were prepared by solution mixing process. The obtained nanocomposites were incorporated in Natural rubber (NR) and Styrene butadiene rubber (SBR) blends in presence of varying types of carbon black as reinforcing fillers. Morphology, curing characteristics, mechanical and thermal properties were characterized and analyzed. Also, the wear characteristics of the nanocomposites against Du-Pont abrader, DIN abrader and different mining rock surfaces were determined and discussed. The morphology of the organoclay incorporated in ENR shows a highly intercalated structure. ISAF type of carbon black shows a significant effect on curing and mechanical properties by reacting at the interface between SBR and NR matrix. All the samples show only one melting peak at same temperature on the DSC curve. Blends containing ISAF N234 type of carbon black shows high abrasion resistant properties against Du-Pont abrader, DIN abrader and different mining rock. The rubber compound containing 70 wt% of NR, 30 wt% of SBR and 10 wt% of ENR/nanoclay with ISAF N231 are found to be the toughest rubber against all types of rock under the present study. PMID:20358894

  16. The Y-Family DNA Polymerase Dpo4 Uses a Template Slippage Mechanism To Create Single-Base Deletions

    SciTech Connect

    Y Wu; R Wilson; J Pata

    2011-12-31

    The Y-family polymerases help cells tolerate DNA damage by performing translesion synthesis, yet they also can be highly error prone. One distinctive feature of the DinB class of Y-family polymerases is that they make single-base deletion errors at high frequencies in repetitive sequences, especially those that contain two or more identical pyrimidines with a 5? flanking guanosine. Intriguingly, different deletion mechanisms have been proposed, even for two archaeal DinB polymerases that share 54% sequence identity and originate from two strains of Sulfolobus. To reconcile these apparent differences, we have characterized Dpo4 from Sulfolobus solfataricus using the same biochemical and crystallographic approaches that we have used previously to characterize Dbh from Sulfolobus acidocaldarius. In contrast to previous suggestions that Dpo4 uses a deoxynucleoside triphosphate (dNTP)-stabilized misalignment mechanism when creating single-base deletions, we find that Dpo4 predominantly uses a template slippage deletion mechanism when replicating repetitive DNA sequences, as was previously shown for Dbh. Dpo4 stabilizes the skipped template base in an extrahelical conformation between the polymerase and the little-finger domains of the enzyme. This contrasts with Dbh, in which the extrahelical base is stabilized against the surface of the little-finger domain alone. Thus, despite sharing a common deletion mechanism, these closely related polymerases use different contacts with the substrate to accomplish the same result.

  17. Recent ground deformation of Taiyuan basin (China) investigated with C-, L-, and X-bands SAR images

    NASA Astrophysics Data System (ADS)

    Zhu, Wu; Zhang, Qin; Ding, Xiaoli; Zhao, Chaoying; Yang, Chengsheng; Qu, Wei

    2013-10-01

    C-, L- and X-bands Synthetic Aperture Radar (SAR) images acquired from November 2006 to June 2011 were processed with Small BAseline Subset DInSAR (SBAS-DInSAR) technique to investigate spatial and temporal variations in deformation over Taiyuan basin, China. The annual deformation rate, created by integrating C-, L- and X-bands interferograms, revealed severe subsidence regions in the basin, where the average subsidence exceeded 10 cm/y and the maximum subsidence reached to 24 cm/y. Meanwhile, it was found that shapes of these subsidence areas were characterized as either subsiding bowls or elongated subsiding belts, implying an intimate connection among groundwater exploration, ground subsidence and faults. Additionally, significant differences in displacement were identified near the faults. This phenomenon could be explained that faults acted as barriers to groundwater flow, impeding the horizontal propagation of fluid-pressure changes and therefore creating groundwater level difference across them. Furthermore, the time series of deformation maps presented inconspicuous nonlinear periodic variations, which might be caused by the seasonal groundwater level fluctuations. In view of the poor water resource and presented features of subsidence over the study area, we deduced that excessive pumping of groundwater was the dominant process driving land subsidence. Our results could provide scientific evidence on a sound management of ground water pumping to mitigate potential damages on infrastructures and environments.

  18. Nuclear Quantum Effects in Water at the Triple Point: Using Theory as a Link Between Experiments.

    PubMed

    Cheng, Bingqing; Behler, Jörg; Ceriotti, Michele

    2016-06-16

    One of the most prominent consequences of the quantum nature of light atomic nuclei is that their kinetic energy does not follow a Maxwell-Boltzmann distribution. Deep inelastic neutron scattering (DINS) experiments can measure this effect. Thus, the nuclear quantum kinetic energy can be probed directly in both ordered and disordered samples. However, the relation between the quantum kinetic energy and the atomic environment is a very indirect one, and cross-validation with theoretical modeling is therefore urgently needed. Here, we use state of the art path integral molecular dynamics techniques to compute the kinetic energy of hydrogen and oxygen nuclei in liquid, solid, and gas-phase water close to the triple point, comparing three different interatomic potentials and validating our results against equilibrium isotope fractionation measurements. We will then show how accurate simulations can draw a link between extremely precise fractionation experiments and DINS, therefore establishing a reliable benchmark for future measurements and providing key insights to increase further the accuracy of interatomic potentials for water. PMID:27203358

  19. Direct Measurements of Quantum Kinetic Energy Tensor in Stable and Metastable Water near the Triple Point: An Experimental Benchmark.

    PubMed

    Andreani, Carla; Romanelli, Giovanni; Senesi, Roberto

    2016-06-16

    This study presents the first direct and quantitative measurement of the nuclear momentum distribution anisotropy and the quantum kinetic energy tensor in stable and metastable (supercooled) water near its triple point, using deep inelastic neutron scattering (DINS). From the experimental spectra, accurate line shapes of the hydrogen momentum distributions are derived using an anisotropic Gaussian and a model-independent framework. The experimental results, benchmarked with those obtained for the solid phase, provide the state of the art directional values of the hydrogen mean kinetic energy in metastable water. The determinations of the direction kinetic energies in the supercooled phase, provide accurate and quantitative measurements of these dynamical observables in metastable and stable phases, that is, key insight in the physical mechanisms of the hydrogen quantum state in both disordered and polycrystalline systems. The remarkable findings of this study establish novel insight into further expand the capacity and accuracy of DINS investigations of the nuclear quantum effects in water and represent reference experimental values for theoretical investigations. PMID:27214268

  20. órbitas: caos en familia

    NASA Astrophysics Data System (ADS)

    Carpintero, D. D.

    Durante los últimos años, ha ido adquiriendo importancia la descripción dinámica de un sistema estelar a través de su estructura orbital, complementando el tradicional uso de la función de distribución en el espacio fase. El desarrollo de esta nueva concepción condujo, con el tiempo, a la conclusión de que las órbitas caóticas juegan un importante papel dinámico en modelos realistas de galaxias. Sin embargo, la determinación de la caoticidad de una órbita, o de la familia regular a la cual pertenece, siguió siendo una tarea artesanal. Nuevos métodos de clasificación fueron surgiendo con el tiempo; hoy en día, se cuenta con métodos que permiten determinar automáticamente el contenido orbital de cualquier potencial arbitrario que se desee para modelar una galaxia, o incluso determinar la familia de una órbita sin siquiera conocer el potencial en el que está sumergida.

  1. Response of benthic algae to environmental gradients in an agriculturally dominated landscape

    USGS Publications Warehouse

    Munn, M.D.; Black, R.W.; Gruber, S.J.

    2002-01-01

    Benthic algal communities were assessed in an agriculturally dominated landscape in the Central Columbia Plateau, Washington, to determine which environmental variables best explained species distributions, and whether algae species optima models were useful in predicting specific water-quality parameters. Land uses in the study area included forest, range, urban, and agriculture. Most of the streams in this region can be characterized as open-channel systems influenced by intensive dryland (nonirrigated) and irrigated agriculture. Algal communities in forested streams were dominated by blue-green algae, with communities in urban and range streams dominated by diatoms. The predominance of either blue-greens or diatoms in agricultural streams varied greatly depending on the specific site. Canonical correspondence analysis (CCA) indicated a strong gradient effect of several key environmental variables on benthic algal community composition. Conductivity and % agriculture were the dominant explanatory variables when all sites (n = 24) were included in the CCA; water velocity replaced conductivity when the CCA included only agricultural and urban sites. Other significant explanatory variables included dissolved inorganic nitrogen (DIN), orthophosphate (OP), discharge, and precipitation. Regression and calibration models accurately predicted conductivity based on benthic algal communities, with OP having slightly lower predictability. The model for DIN was poor, and therefore may be less useful in this system. Thirty-four algal taxa were identified as potential indicators of conductivity and nutrient conditions, with most indicators being diatoms except for the blue-greens Anabaenasp. and Lyngbya sp.

  2. Development and pilot evaluation of a cancer-focused summer research education program for [corrected] Navajo undergraduate students.

    PubMed

    Garrison, Edward R; Bauer, Mark C; Hosley, Brenda L; Patten, Christi A; Hughes, Christine A; Trapp, Mary A; Petersen, Wesley O; Austin-Garrison, Martha A; Bowman, Clarissa N; Vierkant, Robert A

    2010-12-01

    This paper describes the development and pilot testing of a 10-week cancer research education program for Navajo undergraduate students. The program was piloted at Diné College with 22 undergraduates (7 men, 15 women) in 2007 and 2008. Students completed a pre-post program survey assessing attitudes, opinions, and knowledge about research and about cancer. The program was found to be culturally acceptable and resulted in statistically significant changes in some of the attitudes and opinions about research and cancer. Combining all 13 knowledge items, there was a significant (p = 0.002) change in the mean total correct percent from baseline [70.3 (SD = 15.9)] to post-program [82.1 (SD = 13.1)]. The curriculum was adapted for a new cancer prevention and control course now offered at Diné College, enhancing sustainability. Ultimately, these efforts may serve to build capacity in communities by developing a cadre of future Native American scientists to develop and implement cancer research. PMID:20411446

  3. Influence of nutrient input on the trophic state of a tropical brackish water lagoon

    NASA Astrophysics Data System (ADS)

    Ganguly, D.; Patra, Sivaji; Muduli, Pradipta R.; Vardhan, K. Vishnu; R, Abhilash K.; Robin, R. S.; Subramanian, B. R.

    2015-07-01

    Ecosystem level changes in water quality and biotic communities in coastal lagoons have been associated with intensification of anthropogenic pressures. In light of incipient changes in Asia's largest brackish water lagoon (Chilika, India), an examination of different dissolved nutrients distribution and phytoplankton biomass, was conducted through seasonal water quality monitoring in the year 2011. The lagoon showed both spatial and temporal variation in nutrient concentration, mostly altered by freshwater input, regulated the chlorophyll distribution as well. Dissolved inorganic N:P ratio in the lagoon showed nitrogen limitation in May and December, 2011. Chlorophyll in the lagoon varied between 3.38 and 17.66 mg m -3. Spatially, northern part of the lagoon showed higher values of DIN and chlorophyll during most part of the year, except in May, when highest DIN was recorded in the southern part. Statistical analysis revealed that dissolved NH-N and urea could combinedly explain 43% of Chlorophyll- a (Chl- a) variability which was relatively higher than that explained by NO-N and NO-N (12.4%) in lagoon water. Trophic state index calculated for different sectors of the lagoon confirmed the inter-sectoral and inter-seasonal shift from mesotrophic to eutrophic conditions largely depending on nutrient rich freshwater input.

  4. Dermatophyte susceptibility varies towards antimicrobial textiles.

    PubMed

    Hammer, Timo R; Mucha, Helmut; Hoefer, Dirk

    2012-07-01

    Dermatophytoses are a widespread problem worldwide. Textiles in contact with infected skin can serve as a carrier for fungus propagation. Hitherto, it is unknown, whether antifungal textiles could contribute in controlling dermatophytes e.g. by disrupting the chain of infection. Testing of antimicrobial fabrics for their antifungal activities therefore is a fundamental prerequisite to assess the putative clinical relevance of textiles for dermatophyte prevention. Fabrics finished with either didecyldimethylammonium chloride (DDAC), poly-hexamethylenbiguanide, copper and two silver chloride concentrations were tested for their antifungal activity against Trichophyton rubrum, Trichophyton mentagrophytes and Candida albicans. To prove dermatophyte susceptibility towards the textiles, swatches were subjected to DIN EN 14199 (Trichophyton sp.) or DIN EN ISO 20743 (C. albicans) respectively. In addition, samples were embedded, and semi-thin sections were analysed microscopically. While all samples showed a clear inhibition of C. albicans, activity against Trichophyton sp. varied significantly: For example, DDAC completely inhibited T. rubrum growth, whereas T. mentagrophytes growth remained unaffected even in direct contact to the fibres. The results favour to add T. mentagrophytes as a test organism in textile dermatophyte efficacy tests. Microscopic analysis of swatches allowed detailed evaluation of additional parameters like mycelium thickness, density and hyphae penetration depth into the fabric.

  5. Contribution of groundwater discharge to the coastal dissolved nutrients and trace metal concentrations in Majorca Island: karstic vs detrital systems.

    PubMed

    Tovar-Sánchez, Antonio; Basterretxea, Gotzon; Rodellas, Valentí; Sánchez-Quiles, David; García-Orellana, Jordi; Masqué, Pere; Jordi, Antoni; López, José M; Garcia-Solsona, Ester

    2014-10-21

    Submarine groundwater discharge (SGD) and derived nutrient (NO2(-), NO3(-), NH4(+), PO4(3-), and SiO2) and trace element (Cd, Co, Cu, Fe, Mo, Ni, Pb, V and Zn) loadings to the coastal sea were systematically assessed along the coast of Majorca Island, Spain, in a general survey around the island and in three representative coves during 2010. We estimated that brackish water discharges through the shoreline are important contributors to the DIN, SiO2, Fe, and Zn budgets of the nearshore waters. Furthermore, our results showed that SGD-derived elements are conditioned by the hydrogeological formations of the aquifer and discharge type. Thus, while rapid discharges through karstic conduits are enriched in SiO2 and Zn, the large detrital aquifers of the island typically present enhanced concentrations of Fe. The estimated total annual inputs of chemicals constituents discharged by SGD to the coastal waters were as follows: DIN: 610 × 10(3) kg yr(-1), SiO2: 1400 × 10(3) kg yr(-1), Fe: 3.2 × 10(3) kg yr(-1), and Zn: 2.0 × 10(3) kg yr(-1). Our results provide evidence that SGD is a major contributor to the dissolved pool of inorganic nutrients and trace metals in the nearshore waters of Majorca.

  6. Structures of multidrug and toxic compound extrusion transporters and their mechanistic implications.

    PubMed

    Lu, Min

    2016-01-01

    Multidrug resistance poses grand challenges to the effective treatment of infectious diseases and cancers. Integral membrane proteins from the multidrug and toxic compound extrusion (MATE) family contribute to multidrug resistance by exporting a wide variety of therapeutic drugs across cell membranes. MATE proteins are conserved from bacteria to humans and can be categorized into the NorM, DinF and eukaryotic subfamilies. MATE transporters hold great appeal as potential therapeutic targets for curbing multidrug resistance, yet their transport mechanism remains elusive. During the past 5 years, X-ray structures of 4 NorM and DinF transporters have been reported and guided biochemical studies to reveal how MATE transporters extrude different drugs. Such advances, although substantial, have yet to be discussed collectively. Herein I review these structures and the unprecedented mechanistic insights that have been garnered from those structure-inspired studies, as well as lay out the outstanding questions that present exciting opportunities for future work. PMID:26488689

  7. A mechanistic study of plant and microbial controls over R* for nitrogen in an annual grassland.

    PubMed

    Yelenik, Stephanie G; Colman, Benjamin P; Levine, Jonathan M; HilleRisLambers, Janneke

    2014-01-01

    Differences in species' abilities to capture resources can drive competitive hierarchies, successional dynamics, community diversity, and invasions. To investigate mechanisms of resource competition within a nitrogen (N) limited California grassland community, we established a manipulative experiment using an R* framework. R* theory holds that better competitors within a N limited community should better depress available N in monoculture plots and obtain higher abundance in mixture plots. We asked whether (1) plant uptake or (2) plant species influences on microbial dynamics were the primary drivers of available soil N levels in this system where N structures plant communities. To disentangle the relative roles of plant uptake and microbially-mediated processes in resource competition, we quantified soil N dynamics as well as N pools in plant and microbial biomass in monoculture plots of 11 native or exotic annual grassland plants over one growing season. We found a negative correlation between plant N content and soil dissolved inorganic nitrogen (DIN, our measure of R*), suggesting that plant uptake drives R*. In contrast, we found no relationship between microbial biomass N or potential net N mineralization and DIN. We conclude that while plant-microbial interactions may have altered the overall quantity of N that plants take up, the relationship between species' abundance and available N in monoculture was largely driven by plant N uptake in this first year of growth.

  8. Direct Measurements of Quantum Kinetic Energy Tensor in Stable and Metastable Water near the Triple Point: An Experimental Benchmark.

    PubMed

    Andreani, Carla; Romanelli, Giovanni; Senesi, Roberto

    2016-06-16

    This study presents the first direct and quantitative measurement of the nuclear momentum distribution anisotropy and the quantum kinetic energy tensor in stable and metastable (supercooled) water near its triple point, using deep inelastic neutron scattering (DINS). From the experimental spectra, accurate line shapes of the hydrogen momentum distributions are derived using an anisotropic Gaussian and a model-independent framework. The experimental results, benchmarked with those obtained for the solid phase, provide the state of the art directional values of the hydrogen mean kinetic energy in metastable water. The determinations of the direction kinetic energies in the supercooled phase, provide accurate and quantitative measurements of these dynamical observables in metastable and stable phases, that is, key insight in the physical mechanisms of the hydrogen quantum state in both disordered and polycrystalline systems. The remarkable findings of this study establish novel insight into further expand the capacity and accuracy of DINS investigations of the nuclear quantum effects in water and represent reference experimental values for theoretical investigations.

  9. Eliminating "ductal carcinoma in situ" and "lobular carcinoma in situ" (DCIS and LCIS) terminology in clinical breast practice: The cognitive psychology point of view.

    PubMed

    Pravettoni, Gabriella; Yoder, Whitney R; Riva, Silvia; Mazzocco, Ketti; Arnaboldi, Paola; Galimberti, Viviana

    2016-02-01

    There is evidence from the literature that the terms "ductal carcinoma in situ" and "lobular carcinoma in situ" (DCIS and LCIS) should be eliminated in clinical breast cancer practice and replaced with the new "ductal intraepithelial neoplasia" (DIN) and "lobular intraepithelial neoplasia" (LIN) terminology. The main purpose of the present article is to expand on this argument from a cognitive psychology perspective and offer suggestions for further research, emphasizing how the elimination of the term "carcinoma" in "in situ" breast cancer diagnoses has the potential to reduce both patient and health care professional confusion and misperceptions that are often associated with the DCIS and LCIS diagnoses, as well as limit the adverse psychological effects of women receiving a DCIS or LCIS diagnosis. We comment on the recent peer-reviewed literature on the clinical implications and psychological consequences for breast cancer patients receiving a DCIS or LCIS diagnosis and we use a cognitive perspective to offer new insight into the benefits of embracing the new DIN and LIN terminology. Using cognitive psychology and cognitive science in general, as a foundation, further research is advocated in order to yield data in support of changing the terminology and therefore, offer a chance to significantly improve the lives and psychological sequelae of women facing such a diagnosis. Typology: Controversies/Short Commentary.

  10. Benthic metabolism and the fate of dissolved inorganic nitrogen in intertidal sediments

    NASA Astrophysics Data System (ADS)

    Porubsky, W. P.; Weston, N. B.; Joye, S. B.

    2009-08-01

    We determined patterns of benthic metabolism and examined the relative importance of denitrification (DNF) and dissimilatory nitrate reduction to ammonium (DNRA) as sinks for nitrate (NO 3-) in intertidal sediments in the presence and absence of benthic microalgal (BMA) activity. By influencing the activity of BMA, light regulated the metabolic status of the sediments, and, in turn, exerted strong control on sediment nitrogen dynamics and the fate of inorganic nitrogen. A pulsed addition of 15N-labeled NO 3- tracked the effect and fate of dissolved inorganic nitrogen (DIN) in the system. Under illuminated conditions, BMA communities influenced benthic fluxes directly, via DIN uptake, and indirectly, by altering the oxygen penetration depth. Under dark hypoxic and anoxic conditions, the fate of water column NO 3- was determined largely by three competing dissimilatory reductive processes; DNF, DNRA, and, on one occasion, anaerobic ammonium oxidation (anammox). Mass balance of the added 15N tracer illustrated that DNF accounted for a maximum of 48.2% of the 15NO 3- reduced while DNRA (a minimum of 11.4%) and anammox (a minimum of 2.2%) accounted for much less. A slurry experiment was employed to further examine the partitioning between DNF and DNRA. High sulfide concentrations negatively impacted rates of both processes, while high DOC:NO 3- ratios favored DNRA over DNF.

  11. Photometric measurement of color changes in livor mortis as a function of pressure and time. Development of a computer-aided system for measuring pressure-induced blanching of livor mortis to estimate time of death.

    PubMed

    Kaatsch, H J; Stadler, M; Nietert, M

    1993-01-01

    Until now, blanching of livor mortis in estimating time of death has generally been assessed based on subjective impressions, i.e. on whether blanching is visible after the application of pressure. We have developed a measuring system that uses digital processing to objectify the relationship between the pressure applied and blanching of postmortem lividity. The pressure is electronically registered by a strain gauge. At predefined levels (10, 20, 30, up to 100 N) the software triggers a color measurement by a commercially available tristimulus colorimeter. All parameters are measured in a single procedure and routed to the computer through a data interface. The pressure-induced color changes in the livor mortis are evaluated according to the L*, a*, b* system (CIE-LAB according to DIN 5033, DIN 6174), which closely approximates the physiology of sight. An additional color spacing formula (delta E) allows analysis of color changes irrespective of the basic skin tone. Initial measurements on cadavers showed that application of increasing pressure produced regular courses of color changes in livor mortis.

  12. Nuclear Quantum Effects in Water at the Triple Point: Using Theory as a Link Between Experiments.

    PubMed

    Cheng, Bingqing; Behler, Jörg; Ceriotti, Michele

    2016-06-16

    One of the most prominent consequences of the quantum nature of light atomic nuclei is that their kinetic energy does not follow a Maxwell-Boltzmann distribution. Deep inelastic neutron scattering (DINS) experiments can measure this effect. Thus, the nuclear quantum kinetic energy can be probed directly in both ordered and disordered samples. However, the relation between the quantum kinetic energy and the atomic environment is a very indirect one, and cross-validation with theoretical modeling is therefore urgently needed. Here, we use state of the art path integral molecular dynamics techniques to compute the kinetic energy of hydrogen and oxygen nuclei in liquid, solid, and gas-phase water close to the triple point, comparing three different interatomic potentials and validating our results against equilibrium isotope fractionation measurements. We will then show how accurate simulations can draw a link between extremely precise fractionation experiments and DINS, therefore establishing a reliable benchmark for future measurements and providing key insights to increase further the accuracy of interatomic potentials for water.

  13. Multislice simulation of transmission electron microscopy imaging of helium bubbles in Fe.

    PubMed

    Yao, Bo; Edwards, Danny J; Kurtz, Richard J; Odette, G Robert; Yamamoto, Takuya

    2012-01-01

    Formation of nanoscale helium (He) bubbles in reduced activation ferritic/martensitic steels may lead to degradation of mechanical properties of materials. Transmission electron microscopy (TEM) has commonly been used to image the Fresnel contrast of He bubbles, using an underfocus of 0.5-1 µm. This paper presents our study of multislice simulation of the size correlation between imaged Fresnel rings and the actual He bubbles. It was found that for bubbles equal to or >3 nm in diameter, the imaged bubble size, represented by its inner diameter of the first dark Fresnel ring (D(in)) in underfocused imaging conditions, increases with increasing electron-beam incoherency, but decreases with increasing underfocus. The electron-beam accelerating voltage, bubble size, bubble position and TEM sample thickness were found to have no significant influence on the deviation of D(in) from the actual bubble size (D(0)). However, for bubbles equal to or <2 nm, D(in)/D(0) increases dramatically with increasing underfocus when it is above a threshold limit (e.g. Δf = -1 µm for a 2-nm bubble). The results of this study also suggested that He bubbles can be differentiated from argon (Ar) bubbles by contrast differences.

  14. Controls on nitrogen loss processes in Chesapeake Bay sediments.

    PubMed

    Babbin, Andrew R; Ward, Bess B

    2013-05-01

    The flux of fixed nitrogen into the marine environment is increasing as a direct result of anthropogenic nitrogen loading, but the controls on the mechanisms responsible for the removal of this increased supply are not well constrained. The fate of fixed nitrogen via mineralization and nitrogen loss processes was investigated by simulating a settling event of organic matter (OM) in mesocosms containing Chesapeake Bay sediments. Microorganisms rapidly transformed the OM during the course of a seven week incubation ultimately leading to nitrogen loss via denitrification and anaerobic ammonium oxidation (anammox). The microbial community responded quickly to the OM amendment suggesting that estuarine sediments can buffer the natural system against sudden injections of organic material. Two different levels of organic matter amendment resulted in different magnitudes of ammonium and nitrite accumulation during the incubation, but both treatments exhibited the same overall sequence of dissolved inorganic nitrogen (DIN) accumulation and removal. An inverse least-squares analysis coupled to a Michaelis-Menten prognostic model was conducted to estimate rates of nitrogen transformations from the measured DIN concentrations. Whereas the rates were higher at higher OM, the percentage of nitrogen lost via anammox was constant at 44.3 ± 0.3%. The stoichiometry of organic matter and the allochthonous supply of ammonium determined the relative contribution of anammox and denitrification to overall nitrogen loss. Further, in situ thermodynamics based on measured concentrations suggested that the energy favorability of denitrification and anammox plays a role in determining the timing of these processes as OM remineralization progresses.

  15. Chemical composition and biological activity of essential oil from Pulicaria undulata from Yemen.

    PubMed

    Ali, Nasser A Awadh; Sharopov, Farukh S; Alhaj, Mehdi; Hill, Gabrielle M; Porzel, Andrea; Arnold, Norbert; Setzer, William N; Schmidt, Jürgen; Wessjohann, Ludger

    2012-02-01

    The chemical composition of the essential oil obtained from the leaves of Pulicaria undulata Gamal Ed Din (syn P. orientalis sensu Schwartz and P. jaubertii Gamal Ed Din) was analyzed by GC-MS. Major compounds of P. undulata oil were the oxygenated monoterpenenes, carvotanacetone (91.4%) and 2,5-dimethoxy-p-cymene (2.6.%). The antimicrobial activity of the essential oil was evaluated against six microorganisms, Escherichia coli Pseudomonas aeruginosa, Staphylococcus aureus, methicillin-resistant S. aureus, Bacillus subtilis, and Candida albicans, using disc diffusion and broth microdilution methods. The oil showed the strongest bactericidal activity against Staphylococcus aureus and methicillin-resistant S. aureus, as well as Candida albicans. The essential oil showed moderate cytotoxic activity against MCF-7 breast tumor cells, with an IC50 of 64.6 +/- 13.7 microg/mL. Bioautographic assays were used to evaluate the acetylcholinesterase inhibitory effect as well as antifungal activity of the oil against Cladosporium cucumerinum.

  16. Spatio-temporal evolution of aseismic ground deformation in the Mexicali Valley (Baja California, Mexico) from 1993 to 2010, using differential SAR interferometry

    NASA Astrophysics Data System (ADS)

    Sarychikhina, O.; Glowacka, E.

    2015-11-01

    Ground deformation in Mexicali Valley, Baja California, Mexico, the southern part of the Mexicali-Imperial valley, is influenced by active tectonics and human activity, mainly that of geothermal fluid extraction in the Cerro Prieto Geothermal Field. Significant ground deformation, mainly subsidence (~ 18 cm yr-1), and related ground fissures cause severe damage to local infrastructure. The technique of Differential Synthetic Aperture Radar Interferometry (DInSAR) has been demonstrated to be a very effective remote sensing tool for accurately measuring the spatial and temporal evolution of ground displacements over broad areas. In present study ERS-1/2 SAR and ENVISAT ASAR images acquired between 1993 and 2010 were used to perform a historical analysis of aseismic ground deformation in Mexicali Valley, in an attempt to evaluate its spatio-temporal evolution and improve the understanding of its dynamic. For this purpose, the conventional 2-pass DInSAR was used to generate interferograms which were used in stacking procedure to produce maps of annual aseismic ground deformation rates for different periods. Differential interferograms that included strong co-seismic deformation signals were not included in the stacking and analysis. The changes in the ground deformation pattern and rate were identified. The main changes occur between 2000 and 2005 and include increasing deformation rate in the recharge zone and decreasing deformation rate in the western part of the CPGF production zone. We suggested that these changes are mainly caused by production development in the Cerro Prieto Geothermal Field.

  17. Six years of land subsidence in shanghai revealed by JERS-1 SAR data

    USGS Publications Warehouse

    Damoah-Afari, P.; Ding, X.-L.; Li, Z.; Lu, Zhiming; Omura, M.

    2008-01-01

    Differential interferometric synthetic aperture radar (SAR) (DInSAR) has proven to be very useful in mapping and monitoring land subsidence in many regions of the world. Shanghai, China's largest city, is one of such areas suffering from land subsidence as a result of severe withdrawal of groundwater for different usages. DInSAR application in Shanghai with the C-band European Remote Sensing 1 & 2 (ERS-1/2) SAR data has been difficult mainly due to the problem of decorrelation of InSAR pairs with temporal baselines larger than 10 months. To overcome the coherence loss of C-band InSAR data, we used eight L-band Japanese Earth Resource Satellite (JERS-1) SAR data acquired during 2 October 1992 to 15 July 1998 to study land subsidence phenomenon in Shanghai. Three of the images were used to produce two separate digital elevation models (DEMs) of the study area to remove topographic fringes from the interferograms used for subsidence mapping. Six interferograms were used to generate 2 different time series of deformation maps over Shanghai. The cumulative subsidence map generated from each of the time series is in agreement with the land subsidence measurements of Shanghai city from 1990-1998, produced from other survey methods. ?? 2007 IEEE.

  18. Lake and watershed characteristics rather than climate influence nutrient limitation in shallow lakes.

    PubMed

    Kosten, Sarian; Huszar, Vera L M; Mazzeo, Néstor; Scheffer, Marten; Sternberg, Leonel da S L; Jeppesen, Erik

    2009-10-01

    Both nitrogen (N) and phosphorus (P) can limit primary production in shallow lakes, but it is still debated how the importance of N and P varies in time and space. We sampled 83 shallow lakes along a latitudinal gradient (5 degrees 55 degrees S) in South America and assessed the potential nutrient limitation using different methods including nutrient ratios in sediment, water, and seston, dissolved nutrient concentrations, and occurrence of N-fixing cyanobacteria. We found that local characteristics such as soil type and associated land use in the catchment, hydrology, and also the presence of abundant submerged macrophyte growth influenced N and P limitation. We found neither a consistent variation in nutrient limitation nor indications for a steady change in denitrification along the latitudinal gradient. Contrary to findings in other regions, we did not find a relationship between the occurrence of (N-fixing and non-N-fixing) cyanobacteria and the TN:TP ratio. We found N-fixing cyanobacteria (those with heterocysts) exclusively in lakes with dissolved inorganic nitrogen (DIN) concentrations of < 100 microg/L, but notably they were also often absent in lakes with low DIN concentrations. We argue that local factors such as land use and hydrology have a stronger influence on which nutrient is limiting than climate. Furthermore, our data show that in a wide range of climates N limitation does not necessarily lead to cyanobacterial dominance.

  19. Quantum tunneling and vibrational dynamics of ultra-confined water

    NASA Astrophysics Data System (ADS)

    Kolesnikov, Alexander I.; Anovitz, Lawrence M.; Ehlers, Georg; Mamontov, Eugene; Podlesnyak, Andrey; Prisk, Timothy R.; Seel, Andrew; Reiter, George F.

    2015-03-01

    Vibrational dynamics of ultra-confined water in single crystals beryl, the structure of which contains ~ 5 Å diameter channels along the c-axis was studied with inelastic (INS), quasi-elastic (QENS) and deep inelastic (DINS) neutron scattering. The results reveal significantly anisotropic dynamical behavior of confined water, and show that effective potential experienced by water perpendicular to the channels is significantly softer than along them. The observed 7 peaks in the INS spectra (at energies 0.25 to 15 meV), based on their temperature and momentum transfer dependences, are explained by transitions between the split ground states of water in beryl due to water quantum tunneling between the 6-fold equivalent positions across the channels. DINS study of beryl at T=4.3 K shows narrow, anisotropic water proton momentum distribution with corresponding kinetic energy, EK=95 meV, which is much less than was previously observed in bulk water (~150 meV). We believe that the exceptionally small EK in beryl is a result of water quantum tunneling ∖ delocalization in the nanometer size confinement and weak water-cage interaction. The neutron experiment at ORNL was sponsored by the Sci. User Facilities Div., BES, U.S. DOE. This research was sponsored by the Div. Chemical Sci, Geosciences, and Biosciences, BES, U.S. DOE. The STFC RAL is thanked for access to ISIS neutron facilities.

  20. Denitrification, leaching, and river nitrogen export in the Community Earth System Model

    NASA Astrophysics Data System (ADS)

    Nevison, Cynthia; Hess, Peter; Riddick, Stuart; Ward, Dan

    2016-03-01

    River nitrogen export is simulated within the Community Earth System Model (CESM) by coupling nitrogen leaching and runoff fluxes from the Community Land Model (CLM) to the River Transport Model (RTM). The coupled CLM-RTM prognostically simulates the downstream impact of human N cycle perturbation on coastal areas. It also provides a framework for estimating denitrification fluxes of N2 and associated trace gases like N2O in soils and river sediments. An important limitation of the current model is that it only simulates dissolved inorganic nitrogen (DIN) river export, due to the lack of dissolved organic nitrogen (DON) and particulate nitrogen (PN) leaching fluxes in CLM. In addition, the partitioning of soil N loss in CLM between the primary loss pathways of denitrification and N leaching/runoff appears heavily skewed toward denitrification compared to other literature estimates, especially in nonagricultural regions, and also varies considerably among the four model configurations presented here. River N export is generally well predicted in the model configurations that include midlatitude crops, but tends to be underpredicted in rivers that are less perturbed by human agriculture. This is especially true in the tropics, where CLM likely underestimates leaching and runoff of all forms of nitrogen. River export of DIN is overpredicted in some relatively unperturbed Arctic rivers, which may result from excessive N inputs to those regions in CLM. Better representation of N loss in CLM can improve confidence in model results with respect to the core model objective of simulating nitrogen limitation of the carbon cycle.

  1. [Status analysis of nutrients and eutrophication assessment in Shenzhen coastal waters].

    PubMed

    Dai, Ji-cui; Gao, Xiao-wei; Ni, Jin-ren; Yin, Kui-hao

    2009-10-15

    Based on the field data of Shenzhen coastal water quality in 2002-2007, variation characteristics of nutrients including NH4+ -N, NO3- -N, NO2- -N, PO4(3-) -P and DIN were presented. And the correlationships between nutrients and pH, salinity were also investigated. Furthermore, eutrophication index (E), organic pollution index (A) and potential eutrophication were employed to assess the eutrophication degree of Shenzhen coastal waters. Results show that the nutrient levels of east coast are higher than that of west coast. And the peak year of nutrients are 2002 and 2006. The average concentrations of PO4(3-) -P and DIN are 0.007 mg/L and 0.078 mg/L for Shenzhen east coast while 0.090 mg/L and 1.544 mg/L for west coast. Nutrients in Shenzhen coastal waters have negative correlations with pH and salinity. The N/P ratios are all far more than 16 indicating that Shenzhen coast belongs to seriously P-limiting water. Eutrophication degree of Shenzhen east coast is far lower than that of west coast, and the average eutrophication index of east coast is 0.11 while 42.15 for west coast. Furthermore, west coast is classified as P-limiting moderate level potential eutrophication area and even as P-limiting potential eutrophication level.

  2. [Nutrient spatiotemporal distribution and eutrophication process in subsidence waters of Huainan and Huaibei mining areas, China].

    PubMed

    Qu, Xi-Jie; Yi, Qi-Tao; Hu, You-Biao; Yan, Jia-Ping; Yu, Huai-Jun; Dong, Xiang-Lin

    2013-11-01

    A total of eight mining subsidence waters, including five sites in Huainan "Panxie" Mining Areas (PXS-1, PXS-2, PXS-3, PXS-4, and PXS-5) and three sites in Huaibei "Zhu-Yang huang" Mining Areas (HBDH, HBZH, HBNH), were selected to study the nutrient temporal and spatial distribution and trophic states. Among the sites, three sites (PXS-1, PXS-3, and HBDH) showed higher nutrient level and could be classified into moderate eutrophication, whereas the other five were in moderate nutrient level and mild eutrophication. Overall, the nutrient level of Huainan mining subsidence waters was higher than that of Huaibei mining subsidence waters. All the test samples in the two mining areas had a higher ratio of nitrogen to phosphorus (N:P), being 25-117 in Huainan and 17-157 in Huaibei, and with a seasonal variety, the lowest in growth season. The dissolved inorganic phosphorus (DIP) in total phosphorous (TP) occupied a small percentage, being averagely 15.4% and 18.4% in Huainan and Huaibei mining areas, respectively. Nitrate was the main specie of dissolved inorganic nitrogen (DIN), with the ratio of nitrate to DIN being 74% and 89% in Huainan and Huaibei mining areas, respectively. Relative to the waters age, human activities could be one of the main factors responsible for the high nutrient level and the faster eutrophication process of these waters.

  3. Eutrophication assessment and bioremediation strategy using seaweeds co-cultured with aquatic animals in an enclosed bay in China.

    PubMed

    Wu, Hailong; Huo, Yuanzi; Hu, Ming; Wei, Zhangliang; He, Peimin

    2015-06-15

    Intensive mariculture results in a rise in nutrient concentrations, then leads to serious eutrophication in coastal waters. Based on the sampling data obtained between August 2012 and July 2013, the eutrophication status in Yantian Bay was assessed, and the proportion of marine animals co-cultured with seaweeds was evaluated. The nutritional quality index (NQI) ranged from 4.37 to 13.20, indicating serious eutrophication conditions. The annual average ratio of nitrogen/phosphorus (N/P) was 25.19, indicating a nitrogen surplus in this system. DIN was selected as the best parameter to balance seaweed absorption and marine animal DIN production. Gracilaria lemaneiformis and Laminaria japonica were selected as co-cultured seaweeds. The optimal proportion of G. lemaneiformis production was assessed as 20074.14 tonnes. The optimal proportion of L. japonica production was evaluated as 15890.68 tonnes. High-temperature adapted seaweeds should be introduced for removing nutrients releasing by farmed aquatic animals in the summer in Yantian Bay.

  4. [The analytical quality and comparability value of four glucometers from different manufacturers].

    PubMed

    Horovskaia, L A; Lobachevskaia, T V; Chernichuk, O V

    2015-01-01

    The modern laboratory medicine provides observation of requirements to glucometers in line with standard DIN EN ISO 15197-2:2013 for self-control under treatment of patients with diabetes mellitus and registration of biologic types data. The study compared functioning of diagnostic devices in point-of-care of four manufacturers. The samples of whole blood taken from two patients were analyzed in three lots of test-strips with concentration of glucose 4.5 and 11.8 mmol/l using glucometers Accu-Chek Active, One Touch Select, Sattelite Express and Contour TS and reference analyzer Olympus AU 400. The results of measurements were analyzed using technique of separated test of patient. The results demonstrated that precision indicators of measurement of blood glucose on glucometers Accu-Chek Active and One Touch Select were within the scope of quality criteria DIN EN ISO 15197-2:2013. The results of testing of glucometer Sattelite Express exceeded the given criteria under measurement of normoglycemic level of concentration and for Contour TS in all range of measured values.

  5. Contribution of groundwater discharge to the coastal dissolved nutrients and trace metal concentrations in Majorca Island: karstic vs detrital systems.

    PubMed

    Tovar-Sánchez, Antonio; Basterretxea, Gotzon; Rodellas, Valentí; Sánchez-Quiles, David; García-Orellana, Jordi; Masqué, Pere; Jordi, Antoni; López, José M; Garcia-Solsona, Ester

    2014-10-21

    Submarine groundwater discharge (SGD) and derived nutrient (NO2(-), NO3(-), NH4(+), PO4(3-), and SiO2) and trace element (Cd, Co, Cu, Fe, Mo, Ni, Pb, V and Zn) loadings to the coastal sea were systematically assessed along the coast of Majorca Island, Spain, in a general survey around the island and in three representative coves during 2010. We estimated that brackish water discharges through the shoreline are important contributors to the DIN, SiO2, Fe, and Zn budgets of the nearshore waters. Furthermore, our results showed that SGD-derived elements are conditioned by the hydrogeological formations of the aquifer and discharge type. Thus, while rapid discharges through karstic conduits are enriched in SiO2 and Zn, the large detrital aquifers of the island typically present enhanced concentrations of Fe. The estimated total annual inputs of chemicals constituents discharged by SGD to the coastal waters were as follows: DIN: 610 × 10(3) kg yr(-1), SiO2: 1400 × 10(3) kg yr(-1), Fe: 3.2 × 10(3) kg yr(-1), and Zn: 2.0 × 10(3) kg yr(-1). Our results provide evidence that SGD is a major contributor to the dissolved pool of inorganic nutrients and trace metals in the nearshore waters of Majorca. PMID:25215451

  6. Gravity-driven deformation of Tenerife measured by InSAR time series analysis

    NASA Astrophysics Data System (ADS)

    Fernández, J.; Tizzani, P.; Manzo, M.; Borgia, A.; González, P. J.; Martí, J.; Pepe, A.; Camacho, A. G.; Casu, F.; Berardino, P.; Prieto, J. F.; Lanari, R.

    2009-02-01

    We study the state of deformation of Tenerife (Canary Islands) using Differential Synthetic Aperture Radar Interferometry (DInSAR). We apply the Small BAseline Subset (SBAS) DInSAR algorithm to radar images acquired from 1992 to 2005 by the ERS sensors to determine the deformation rate distribution and the time series for the coherent pixels identified in the island. Our analysis reveals that the summit area of the volcanic edifice is characterized by a rather continuous subsidence extending well beyond Las Cañadas caldera rim and corresponding to the dense core of the island. These results, coupled with GPS ones, structural and geological information and deformation modeling, suggest an interpretation based on the gravitational sinking of the dense core of the island into a weak lithosphere and that the volcanic edifice is in a state of compression. We also detect more localized deformation patterns correlated with water table changes and variations in the deformation time series associated with the seismic crisis in 2004.

  7. Microbiological irrigation water quality of the Marchfeld canal system.

    PubMed

    Stauffer, F; Makristathis, A; Hassl, A; Nowotny, S; Neudorfer, W

    2001-07-01

    The Marchfeld basin with a size of approximately 1000 km2 represents the Austrian "granary". To prevent shortage of water as a result of increased ground water removal for irrigation, industrial purposes and drinking water supply, a canal being 18 km in length was constructed from the Danube to the center of the Marchfeld. From there, water is further distributed via two creeks (Russbach and Stempfelbach). This study was intended to evaluate whether the surface water of the Marchfeld canal system can be classified into hygienic-microbiological categories as proposed by DIN (Deutsche Industrienorm) standards for irrigation water. For this purpose, water sampled monthly from three different sampling sites from 1996 to 1999 was examined for E. coli and enterococci. In addition, water samples were examined for salmonella twice a year from 1996 to 1998 and for cryptosporidia six times during the year 1999. Though the water showed varying degrees of fecal load, the results of the examinations revealed that only one of the three sampling sites showed constant quality levels according to the DIN classification system over prolonged periods of time. However, exceeding of the limit values was occasionally observed indicating the need for regular bacteriological examinations. The high variation of the results from the other sampling sites hardly permits a definite classification in one of the quality classes. PMID:11556148

  8. Nutrient budgets and trophic state in a hypersaline coastal lagoon: Lagoa de Araruama, Brazil

    NASA Astrophysics Data System (ADS)

    Souza, Marcelo F. L.; Kjerfve, Björn; Knoppers, Bastiaan; Landim de Souza, Weber F.; Damasceno, Raimundo N.

    2003-08-01

    Lagoa de Araruama in the state of Rio de Janeiro, Brazil, is a hypersaline lagoon with salinity varying spatially from 45 to 56. We collected water samples during monthly cruises throughout the lagoon, and along the streams feeding the system, from April 1991 to March 1992. Nutrients and other water quality parameters exhibited great spatial and temporal variations. Mass balance calculations indicate large amounts of anthropogenic nutrient inputs. The data indicate that the lagoon currently is oligotrophic but is in a state of transition to become a mesotrophic system. Molar dissolved inorganic nitrogen:dissolved inorganic phosphorus (DIN/DIP) varied between 2.2:1 and 659:1 with a volume-weighted average of 22:1. The high DIN/DIP ratio contrasts with that found in nearby lagoons, suggesting that phytoplankton primary production is limited by phosphorus in Lagoa de Araruama. The major loss of DIP is apparently driven by biological assimilation and diagenic reactions in the sediments. Calculations indicate that the lagoon is slightly net autotrophic at +0.9 mol C m -2 yr -1. This suggests that the biomass of the primary producers is restricted by phosphorus availability. Phosphorus retention in the sediment and the hypersaline state of the lagoon prevent changes in autotrophic communities and the formation of eutrophic conditions.

  9. Tolerance of Escherichia coli to fluoroquinolone antibiotics depends on specific components of the SOS response pathway.

    PubMed

    Theodore, Alyssa; Lewis, Kim; Vulic, Marin

    2013-12-01

    Bacteria exposed to bactericidal fluoroquinolone (FQ) antibiotics can survive without becoming genetically resistant. Survival of these phenotypically resistant cells, commonly called "persisters," depends on the SOS gene network. We have examined mutants in all known SOS-regulated genes to identify functions essential for tolerance in Escherichia coli. The absence of DinG and UvrD helicases and the Holliday junction processing enzymes RuvA and RuvB leads to a decrease in survival. Analysis of the respective mutants indicates that, in addition to repair of double-strand breaks, tolerance depends on the repair of collapsed replication forks and stalled transcription complexes. Mutation in recF results in increased survival, which identifies RecAF recombination as a poisoning mechanism not previously linked to FQ lethality. DinG acts upstream of SOS promoting its induction, whereas RuvAB participates in repair only. UvrD directly promotes all repair processes initiated by FQ-induced damage and prevents RecAF-dependent misrepair, making it one of the crucial SOS functions required for tolerance.

  10. Phytoplankton along the coastal shelf of an oligotrophic hypersaline environment in a semi-enclosed marginal sea: Qatar (Arabian Gulf)

    NASA Astrophysics Data System (ADS)

    Quigg, Antonietta; Al-Ansi, Mohsin; Al Din, Nehad Nour; Wei, Chih-Lin; Nunnally, Clifton C.; Al-Ansari, Ibrahim S.; Rowe, Gilbert T.; Soliman, Yousria; Al-Maslamani, Ibrahim; Mahmoud, Ismail; Youssef, Nabiha; Abdel-Moati, Mohamed A.

    2013-06-01

    Phytoplankton biomass (chlorophyll a concentration), primary production, abundance, species diversity and species groupings were measured in the coastal waters surrounding Qatar (Arabian Gulf) at 13 stations in February 2010, July 2010, February 2011 and May 2011. In addition, a broad suite of physico-chemical characteristics were measured: temperature, salinity, pH, dissolved oxygen, turbidity, and nutrients (dissolved and particulate). Waters surrounding the Qatari peninsula were found to be highly diverse (125 species of diatoms, dinoflagellates and cyanobacteria were identified) but were low in both biomass (0.18-2.19 μg Chl a l-1) and productivity (0.14-0.97 mg C m-2 day-1). Phytoplankton physiology (Fv/Fm, σPSII, τQa, p) revealed acclimation strategies consistent with phytoplankton populations receiving ample light but insufficient nutrients. The finding of low primary production is consistent with water column nutrient ratios (DIN:P and DIN:Si ratios<1) and nutrient enrichment experiments in which the addition of nitrate or the addition of near-bottom waters stimulated biomass production of phytoplankton. This study in an oligotrophic, hypersaline semi-enclosed marginal sea is intended to contribute to the growing body of ecological information on this ecosystem functions.

  11. Recent results on bulk laser damage threshold of optical glasses

    NASA Astrophysics Data System (ADS)

    Jedamzik, Ralf; Elsmann, Frank

    2013-02-01

    Modern pulsed laser applications cover a broad range of wavelength, power and pulse widths. Beam guiding optics in laser systems do not only have specific requirements on the imaging quality but also have to withstand high laser power. The laser damage threshold of an optical component depends on the surface (polishing, coating ...) and also on the bulk material properties. Actual values of bulk laser damage thresholds, particularly at pulse lengths less than 1 nanosecond (1 ns), of optical glasses are rarely found in literature, except for fused silica, which is known as a key optical material for components in high power laser. However, fused silica is rather expensive and limited in optical properties. That is the reason why customers often ask for laser damage threshold data of optical glasses. Therefore, SCHOTT has started a project for the characterization of the bulk laser damage threshold of optical glasses at the wavelengths 532 nm and 1064 nm with pulse lengths in the nano- and pico-second range. Bulk and surface laser damage testing has been performed by the Laser Zentrum Hannover in Germany according to the S-on-1 test of DIN EN ISO 11254-2 / DIN EN ISO 21254.

  12. Bacterioplankton dynamics along the gradient from highly eutrophic Pearl River Estuary to oligotrophic northern South China Sea in wet season: implication for anthropogenic inputs.

    PubMed

    Zhou, Weihua; Long, Aimin; Jiang, Tao; Chen, Shaoyong; Huang, Liangmin; Huang, Hui; Cai, Chuanghua; Yan, Yan

    2011-04-01

    Bacterioplankton abundance (BA) and biomass (BB) from the eutrophic Pearl River Estuary (PRE) to the oligotrophic northern South China Sea (NSCS) were studied in the wet season. BA was significantly higher (p < 0.05) in PRE (12.51 ± 3.52 x 10⁸ cells L⁻¹), than in the continental shelf neritic province (CSNP, 4.95 ± 2.21 x 10⁸ cells L⁻¹) and in the deep oceanic province (OP, 3.16 ± 1.56 x 10⁸ cells L⁻¹). Nutrient-replete PRE waters (DIN > 100 μM and PO₄ > 1 μM) resulted in high chl a and BB, whereas nutrient-depleted offshore waters (DIN < 5 μM and PO₄ < 0.5 μM) had low biomass. Temperature (> 26 °C) was not the controlling factor of BA. BB was significantly correlated with chl a biomass both in PRE and NSCS. The bacteria to phytoplankton biomass (BB/PB) ratio increased clearly along the gradient from near-shore PRE (0.15) to offshore CSNP (0.93) and deep OP (2.75), indicating the important role of small cells in the open ocean compared to estuarine and coastal zones.

  13. How to measure heat capacity of metals at 10s to 100s of GPa

    NASA Astrophysics Data System (ADS)

    Geballe, Z. M.; Townley, A.; Jeanloz, R.

    2014-12-01

    Adapting methods of calorimetry to the diamond-anvil cell can provide important new information for understanding planetary interiors. Here we show that heat capacity of metals can be measured to the 10-100 GPa range by using AC electrical heating inside diamond anvil cells. Frequencies of f ≈ 1-100 MHz must be used to contain the heat within the sample of interest, as evidenced by numerical and physical models of heat flow: f > DinsCins2/(Csamdsam)2, where Dins is the thermal diffusivity of the insulation, Cins and Csam are specific heat capacities of insulation and metal sample, and dsam is sample thickness. Heat must be deposited uniformly (e.g. skin depth > sample thickness) for the most accurate and unambiguous measurements, thereby allowing measurement of the energetics of pre-melting, melting and partial melting of metals, including iron and its alloys. In principle, high-pressure calorimetry can be used to independently determine melting at high pressures, and also to quantify latent heats of fusion, thereby revealing the density of liquid metals at Earth core conditions.

  14. Dynamic seasonal nitrogen cycling in response to anthropogenic N loading in a tropical catchment, Athi-Galana-Sabaki River, Kenya

    NASA Astrophysics Data System (ADS)

    Marwick, T. R.; Tamooh, F.; Ogwoka, B.; Teodoru, C.; Borges, A. V.; Darchambeau, F.; Bouillon, S.

    2014-01-01

    As part of a broader study on the riverine biogeochemistry in the Athi-Galana-Sabaki (A-G-S) River catchment (Kenya), we present data constraining the sources, transit and transformation of multiple nitrogen (N) species as they flow through the A-G-S catchment (~47 000 km2). The data set was obtained in August-September 2011, November 2011, and April-May 2012, covering the dry season, short rain season and long rain season respectively. Release of (largely untreated) wastewater from the city of Nairobi had a profound impact on the biogeochemistry of the upper Athi River, leading to low dissolved oxygen (DO) saturation levels (36-67%), high ammonium (NH4+) concentrations (123-1193 μmol L-1), and high dissolved methane (CH4) concentrations (3765-6729 nmol L-1). Riverine dissolved inorganic nitrogen (DIN; sum of NH4+ and nitrate (NO3-); nitrite was not measured) concentration at the most upstream site on the Athi River was highest during the dry season (1195 μmol L-1), while DIN concentration was an order of magnitude lower during the short and long rain seasons (212 and 193 μmol L-1, respectively). During the rain seasons, low water residence time led to relatively minimal in-stream N cycling prior to discharge to the ocean, whereas during the dry season we speculate that prolonged residence time creates two differences comparative to wet season, where (1) intense N cycling and removal of DIN is possible in the upper to mid-catchment and leads to significantly lower concentrations at the outlet during the dry season, and (2) as a result this leads to the progressive enrichment of 15N in the particulate N (PN) pool, highlighting the dominance of untreated wastewater as the prevailing source of riverine DIN. The rapid removal of NH4+ in the upper reaches during the dry season was accompanied by a quantitatively similar production of NO3- and nitrous oxide (N2O) downstream, pointing towards strong nitrification over this reach during the dry season. Nitrous oxide

  15. A sustainability model based on cloud infrastructures for core and downstream Copernicus services

    NASA Astrophysics Data System (ADS)

    Manunta, Michele; Calò, Fabiana; De Luca, Claudio; Elefante, Stefano; Farres, Jordi; Guzzetti, Fausto; Imperatore, Pasquale; Lanari, Riccardo; Lengert, Wolfgang; Zinno, Ivana; Casu, Francesco

    2014-05-01

    The incoming Sentinel missions have been designed to be the first remote sensing satellite system devoted to operational services. In particular, the Synthetic Aperture Radar (SAR) Sentinel-1 sensor, dedicated to globally acquire over land in the interferometric mode, guarantees an unprecedented capability to investigate and monitor the Earth surface deformations related to natural and man-made hazards. Thanks to the global coverage strategy and 12-day revisit time, jointly with the free and open access data policy, such a system will allow an extensive application of Differential Interferometric SAR (DInSAR) techniques. In such a framework, European Commission has been funding several projects through the GMES and Copernicus programs, aimed at preparing the user community to the operational and extensive use of Sentinel-1 products for risk mitigation and management purposes. Among them, the FP7-DORIS, an advanced GMES downstream service coordinated by Italian National Council of Research (CNR), is based on the fully exploitation of advanced DInSAR products in landslides and subsidence contexts. In particular, the DORIS project (www.doris-project.eu) has developed innovative scientific techniques and methodologies to support Civil Protection Authorities (CPA) during the pre-event, event, and post-event phases of the risk management cycle. Nonetheless, the huge data stream expected from the Sentinel-1 satellite may jeopardize the effective use of such data in emergency response and security scenarios. This potential bottleneck can be properly overcome through the development of modern infrastructures, able to efficiently provide computing resources as well as advanced services for big data management, processing and dissemination. In this framework, CNR and ESA have tightened up a cooperation to foster the use of GRID and cloud computing platforms for remote sensing data processing, and to make available to a large audience advanced and innovative tools for DIn

  16. Investigation of Colored Dissolved Organic Matter (CDOM) Optical Properties, Nutrients, and Salinity in Coastal Florida: Springshed to Estuaries

    NASA Astrophysics Data System (ADS)

    Arellano, Ana Rosa

    Optical parameters measured via absorption spectroscopy and high-resolution fluorescence spectroscopy were used to characterize dissolved organic matter (DOM) in the springshed of Kings Bay, a spring-fed estuary located on Florida's Springs Coast. Over the past 40 years, springs supplying groundwater to Kings Bay have shown an increase in nitrate concentration. The overall goal of this project was to fingerprint wells and spring sites with elevated nitrogen concentrations using CDOM optical properties and establish relationships between nutrient and optical parameters. Samples were obtained from various sites: springs, Kings Bay surface (KBS), wells, coastal waters in and at the mouth of Crystal River (Coast) and lakes and rivers (LNR), during dry and wet seasons. The relationships between the environmental parameters and traditional optical parameters which provide insight into source characteristics were analyzed. Excitation emission matrix spectroscopy (EEMS) provided information about the concentration and chemical nature of organic matter in the study area. CDOM optical properties combined with salinity clearly separated the sources of fixed nitrogen in the Bay. Northern springs with elevated dissolved inorganic nitrogen (DIN) concentration had lower salinities and showed a presence of protein peaks. CDOM concentration was negatively correlated with total nitrogen (TN) and DIN, which suggests that these are subjected to anthropogenic influences. Humic peaks dominated the composition of the southern springs. CDOM concentrations were much higher than in the northern springs and there was a positive correlation between CDOM and both TN and DIN. These findings suggest that the fixed nitrogen in the southern springs is naturally occurring organic matter and the low concentrations may partially be a result of subsurface mixing of saltwater and freshwater in the aquifer. Thus, hypothesis testing showed that there was a significant difference between northern and

  17. Soluble reactive phosphorus (SRP) transport and retention in tropical, rain forest streams draining a volcanic landscape in Costa Rica: In situ SRP amendment to streams and laboratory studies

    USGS Publications Warehouse

    Triska, F.; Pringle, C.M.; Duff, J.H.; Avanzino, R.J.; Zellweger, G.

    2006-01-01

    Soluble reactive phosphorus (SRP) transport/retention was determined in two rain forest streams (Salto, Pantano) draining La Selva Biological Station, Costa Rica. There, SRP levels can be naturally high due to groundwater enriched by geothermal activity within the surfically dormant volcanic landscape, and subsequently discharged at ambient temperature. Combined field and laboratory approaches simulated high but natural geothermal SRP input with the objective of estimating the magnitude of amended SRP retention within high and low SRP settings and determining the underlying mechanisms of SRP retention. First, we examined short-term SRP retention/transport using combined SRP-conservative tracer additions at high natural in situ concentrations. Second, we attempted to observe a DIN response during SRP amendment as an indicator of biological uptake. Third, we determined SRP release/retention using laboratory sediment assays under control and biologically inhibited conditions. Short-term in situ tracer-SRP additions indicated retention in both naturally high and low SRP reaches. Retention of added SRP mass in Upper Salto (low SRP) was 17% (7.5 mg-P m-2 h-1), and 20% (10.9 mg-P m-2 h -1) in Lower Salto (high SRP). No DIN response in either nitrate or ammonium was observed. Laboratory assays using fresh Lower Salto sediments indicated SRP release (15.4 ?? 5.9 ??g-P g dry wt.-1 h -1), when incubated in filter sterilized Salto water at ambient P concentration, but retention when incubated in filter sterilized river water amended to 2.0 mg SRP l-1 (233.2 ?? 5.8 ??g-P g dry wt. -1 h-1). SRP uptake/release was similar in both control- and biocide-treated sediments indicating predominantly abiotic retention. High SRP retention even under biologically saturated conditions, absence of a DIN response to amendment, patterns of desorption following amendment, and similar patterns of retention and release under control and biologically inhibited conditions all indicated

  18. A time series deformation estimation in the NW Himalayas using SBAS InSAR technique

    NASA Astrophysics Data System (ADS)

    Kumar, V.; Venkataraman, G.

    2012-12-01

    A time series land deformation studies in north western Himalayan region has been presented in this study. Synthetic aperture radar (SAR) interferometry (InSAR) is an important tool for measuring the land displacement caused by different geological processes [1]. Frequent spatial and temporal decorrelation in the Himalayan region is a strong impediment in precise deformation estimation using conventional interferometric SAR approach. In such cases, advanced DInSAR approaches PSInSAR as well as Small base line subset (SBAS) can be used to estimate earth surface deformation. The SBAS technique [2] is a DInSAR approach which uses a twelve or more number of repeat SAR acquisitions in different combinations of a properly chosen data (subsets) for generation of DInSAR interferograms using two pass interferometric approach. Finally it leads to the generation of mean deformation velocity maps and displacement time series. Herein, SBAS algorithm has been used for time series deformation estimation in the NW Himalayan region. ENVISAT ASAR IS2 swath data from 2003 to 2008 have been used for quantifying slow deformation. Himalayan region is a very active tectonic belt and active orogeny play a significant role in land deformation process [3]. Geomorphology in the region is unique and reacts to the climate change adversely bringing with land slides and subsidence. Settlements on the hill slopes are prone to land slides, landslips, rockslides and soil creep. These hazardous features have hampered the over all progress of the region as they obstruct the roads and flow of traffic, break communication, block flowing water in stream and create temporary reservoirs and also bring down lot of soil cover and thus add enormous silt and gravel to the streams. It has been observed that average deformation varies from -30.0 mm/year to 10 mm/year in the NW Himalayan region . References [1] Massonnet, D., Feigl, K.L.,Rossi, M. and Adragna, F. (1994) Radar interferometry mapping of

  19. spatial and temporal distribution of nutrients in a linked stream-lake ecosystem

    NASA Astrophysics Data System (ADS)

    Kalinin, A. V.; Covino, T. P.; McGlynn, B. L.

    2011-12-01

    The movement of nutrients between streams and lakes can impact nutrient export and aquatic ecology in linked stream-lake ecosystems. Specifically, lakes can alter water chemistry and buffer downstream export of nutrients through physical, chemical, and biological processes. This study characterizes nitrogen storage and transport dynamics in a connected stream-lake ecosystem over the summer of 2008 in the Bull Trout Lake Watershed in the Sawtooth Mountains of central Idaho, USA. Water samples were collected for chemical analyses at the lake inflow, outflow, and at six sites across the lake, on hourly to bi-weekly intervals. Lake sampling sites were each sampled at six depths in order to capture all strata of the lake. Additionally, a dye-tracer (Rhodamine-WT) was co-injected with LiCl into the lake to determine water flow-paths and residence time distributions. Inflow and outflow fluxes, spatial and temporal distributions of dissolved organic nitrogen(DON) and dissolved inorganic nitrogen (DIN), as well as water residence times at different lake depths were evaluated. Over the summer of 2008, net influx of NO3 to the lake and net export of DON and NH4 from the lake was observed. While NO3 dominated the DIN fraction at the inflow, NH4 was dominant both at the lake outflow and within the lake, suggesting potential contributions of NH4 to the lake from adjacent wetland and groundwater sources. Differences in transport dynamics between NO3 and NH4, and temporal concentration dynamics both in the stream and lake support this hypothesis. NO3 concentrations were driven by snowmelt flushing and peaked with the hydrograph, subsequently declining for the rest of the summer. NH4 concentrations however remained stable and peaked three weeks after NO3 at the lake outflow, at a time when the contribution of snow melt water had declined and groundwater contribution increased proportionally. In the lake, NH4 and DON concentrations declined during peak runoff in May and June, and

  20. The influence of a lake-wetland complex on catchment nutrient flux and speciation

    NASA Astrophysics Data System (ADS)

    Covino, T. P.; McGlynn, B. L.; Kalinin, A.

    2013-12-01

    Lakes and wetlands within stream networks can substantially alter the timing, magnitude, and form of nutrient export to downstream receiving bodies. These linked systems have the capacity to alter water chemistry and buffer downstream export of nutrients through combined physical, chemical, and biological processes. In many mountainous catchments wetlands are located at the inlet of lakes, thus forming lake-wetland complexes. In this study we investigated the influence an in network lake-wetland complex exerted on the timing, magnitude, and form of carbon and nitrogen export from the Bull Trout Lake Watershed (11.4 km2) located in the Sawtooth Mountains of central Idaho, USA. We: 1) injected conservative tracer to determine lake residence times; and 2) sampled the lake inflow, outflow, and six sites across the lake on hourly to bi-weekly intervals over 5 months (May - September) to capture the spatial and temporal dynamics of injected tracers and catchment nutrient fluxes. Lake sampling sites were each sampled at six depths to capture all strata of the lake. Injected tracer had a median travel time of one week and a modal travel time of four days. Additionally, longer residence times were observed in deeper (>8 m) regions of the lake. We observed that nitrate (NO3-N) was the dominant form of dissolved inorganic nitrogen (DIN) at the lake inflow whereas ammonium (NH4-N) became the dominant component at the lake outflow. Specifically, NO3-N accounted for 62% of DIN at the inflow and NH4-N comprised 58% percent of DIN at the lake outflow 600 m downstream. Dissolved organic nitrogen (DON) comprised the majority of total dissolved nitrogen (TDN) at both the lake inflow and outflow, and within the lake accounting for 92% of the seasonal TDN flux. There was a positive net export of NH4-N, DON, TDN, and dissolved organic carbon (DOC) and a negative net flux of NO3-N from the inlet to the outlet of the lake-wetland complex. Additionally, we observed high concentrations of

  1. Evaluation of a novel inhalation exposure system to determine acute respiratory responses to tobacco and polymer pyrolysate mixtures in Swiss-Webster mice.

    PubMed

    Werley, Michael S; Lee, K Monica; Lemus, Ranulfo

    2009-07-01

    Modern cigarette production processes are highly automated and yield millions of cigarettes per day. The forming cigarette and its components contact many different materials in the production process, some of which may leave minute residues. The potential for small inclusions of non-cigarette materials such as wood, plastic, cardboard and other materials exists from the bulk handling and processing of tobacco, in spite of vigilant workers and numerous online systems designed to keep the tobacco stream clean. Currently, there are no published methods that describe an approach to evaluate the potential toxicological impact of these non-tobacco residues and inclusions on the biological activity from exposure to the complex mixture of tobacco smoke. There are, however, many methods which describe toxicological evaluation approaches for pure materials, particularly synthetic polymers. We used the Deutsche Institute fur Normung (DIN) 53-436 tube furnace and nose-only exposure chamber in combination to conduct pilot studies in Swiss-Webster mice in order to develop a standardized methodology for the evaluation of sensory irritation and other potentially useful biological endpoints for predicting any potential hazards. Sensory and/or pulmonary irritation was assessed based on respiratory function parameters using the ASTM E981-84 method described by Alarie (1966) in mice, exposed to test atmospheres of 100% tobacco pyrolysate or tobacco/polymer pyrolysate mixtures. Other biological evaluations included respiratory function parameters, clinical signs, body weights, bronchoalveolar lavage fluid analysis, carboxyhemoglobin, blood cyanide concentrations and histopathology of the respiratory tract. These pilot studies have demonstrated that such an approach can detect biological changes resulting from exposure to unique tobacco/polymer pyrolysates. Small differences were detected in the sensory irritation responses (respiratory function), activation state of pulmonary

  2. Momentum and energy dependent resolution function of the ARCS neutron chopper spectrometer at high momentum transfer: Comparing simulation and experiment

    NASA Astrophysics Data System (ADS)

    Diallo, S. O.; Lin, J. Y. Y.; Abernathy, D. L.; Azuah, R. T.

    2016-11-01

    Inelastic neutron scattering at high momentum transfers (i.e. Q ≥ 20 A ˚), commonly known as deep inelastic neutron scattering (DINS), provides direct observation of the momentum distribution of light atoms, making it a powerful probe for studying single-particle motions in liquids and solids. The quantitative analysis of DINS data requires an accurate knowledge of the instrument resolution function Ri(Q , E) at each momentum Q and energy transfer E, where the label i indicates whether the resolution was experimentally observed i = obs or simulated i=sim. Here, we describe two independent methods for determining the total resolution function Ri(Q , E) of the ARCS neutron instrument at the Spallation Neutron Source, Oak Ridge National Laboratory. The first method uses experimental data from an archetypical system (liquid 4He) studied with DINS, which are then numerically deconvoluted using its previously determined intrinsic scattering function to yield Robs(Q , E). The second approach uses accurate Monte Carlo simulations of the ARCS spectrometer, which account for all instrument contributions, coupled to a representative scattering kernel to reproduce the experimentally observed response S(Q , E). Using a delta function as scattering kernel, the simulation yields a resolution function Rsim(Q , E) with comparable lineshape and features as Robs(Q , E), but somewhat narrower due to the ideal nature of the model. Using each of these two Ri(Q , E) separately, we extract characteristic parameters of liquid 4He such as the intrinsic linewidth α2 (which sets the atomic kinetic energy < K > ∼α2) in the normal liquid and the Bose-Einstein condensate parameter n0 in the superfluid phase. The extracted α2 values agree well with previous measurements at saturated vapor pressure (SVP) as well as at elevated pressure (24 bars) within experimental precision, independent of which Ri(Q , y) is used to analyze the data. The actual observed n0 values at each Q vary little

  3. Hydrological and Biogeochemical Controls on Seasonal and Spatial Differences in Food Webs in the Everglades

    NASA Astrophysics Data System (ADS)

    Kendall, C.; Wankel, S. D.; Bemis, B. E.; Rawlik, P. S.; Krabbenhoft, D. P.; Lange, T.

    2002-05-01

    Stable isotopes can be used to determine the relative trophic positions of biota within a food web, and to improve our understanding of the biomagnification of contaminants. Plants at the base of the food web uptake dissolved organic carbon (DIC) and nitrogen (DIN) for growth, and their tissue reflects the isotopic composition of these sources. Animals then mirror the isotopic composition of the primary producers, as modified by consumer-diet fractionations at successive trophic steps. During 1995-99, we collected algae, macrophyte, invertebrate, and fish samples from 15 USGS sites in the Everglades and analyzed them for d13C and d15N with the goal of characterizing seasonal and spatial differences in food web relations. Carbon isotopes effectively distinguish between two main types of food webs: ones where algae is the dominant base of the food web, which are characteristic of relatively pristine marsh sites with long hydroperiods, and ones where macrophyte debris appears to be a significant source of nutrients, which are apparently characteristic of shorter hydroperiod sites, and nutrient-impacted marshes and canals. There usually is an inverse relation between d13C and d15N of organisms over time, especially in more pristine environments, reflecting seasonal changes in the d13C of DIC and the d15N of DIN. The d13C and d15N of algae also show strong positive correlations with seasonal changes in water levels. This variability is substantially damped up the food chain, probably because of the longer integration times of animals vs. plants. We speculate that these seasonal shifts in water level result in changes in biogeochemical reactions and nutrient levels, with corresponding variations in the d15N and d13C of biota. For example, small changes in water level may change the balance of photosynthesis, bacterial respiration, and atmospheric exchange reactions that control the d13C of DIC. Such changes will probably also affect the d15N of dissolved inorganic N (DIN

  4. Growth of a young pingo in the Canadian Arctic observed by RADARSAT-2 interferometric satellite radar

    NASA Astrophysics Data System (ADS)

    Samsonov, Sergey V.; Lantz, Trevor C.; Kokelj, Steven V.; Zhang, Yu

    2016-04-01

    Advancements in radar technology are increasing our ability to detect Earth surface deformation in permafrost environments. In this paper we use satellite Differential Interferometric Synthetic Aperture Radar (DInSAR) to describe the growth of a large, relatively young pingo in the Tuktoyaktuk Coastlands. High-resolution RADARSAT-2 imagery (2011-2014) analyzed with the Multidimensional Small Baseline Subset (MSBAS) DInSAR revealed a maximum 2.7 cm yr-1 of domed uplift located in a drained lake basin. Satellite measurements suggest that this feature is one of the largest diameter pingos in the region that is presently growing. Observed changes in elevation were modeled as a 348 × 290 m uniformly loaded elliptical plate with clamped edge. Analysis of historical aerial photographs suggested that ground uplift at this location initiated sometime between 1935 and 1951 following drainage of the residual pond. Uplift is largely due to the growth of intrusive ice, because the 9 % expansion of pore water associated with permafrost aggradation into saturated sands is not sufficient to explain the observed short- and long-term deformation rates. The modeled thickness of ice-rich permafrost using the Northern Ecosystem Soil Temperature (NEST) was consistent with the maximum height of this feature. Modeled permafrost aggradation from 1972 to 2014 approximated elevation changes estimated from aerial photographs for that time period. Taken together, these lines of evidence indicate that uplift is at least in part a result of freezing of the sub-pingo water lens. Seasonal variations in the uplift rate seen in the DInSAR data closely match the modeled seasonal pattern in the deepening rate of freezing front. This study demonstrates that interferometric satellite radar can detect and contribute to understanding the dynamics of terrain uplift in response to permafrost aggradation and ground ice development in remote polar environments. The present-day growth rate is smaller than

  5. Synergistic effects of inositol 1,3,4,5-tetrakisphosphate on inositol 2,4,5-triphosphate-stimulated Ca2+ release do not involve direct interaction of inositol 1,3,4,5-tetrakisphosphate with inositol triphosphate-binding sites.