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• 411. [Article] Relationship of pore water freshening to accretionary processes in the Cascadia margin: Fluid sources and gas hydrate abundance

  Drilling in the Cascadia accretionary complex enable us to evaluate the contribution of dehydration reactions and gas hydrate dissociation to pore water freshening. The observed freshening with depth and ...

  Citation × Citation Citation Abstract Copy Title: Relationship of pore water freshening to accretionary processes in the Cascadia margin: Fluid sources and gas hydrate abundance Author: Torres, Marta E., Tomaru, H., Teichert, B. M. A., Borowski, W., Tréhu, Anne Martine Drilling in the Cascadia accretionary complex enable us to evaluate the contribution of dehydration reactions and gas hydrate dissociation to pore water freshening. The observed freshening with depth and distance from the prism toe is consistent with enhanced conversion of smectite to illite, driven by increase in temperature and age of accreted sediments. Although they contain gas hydrate -as evidenced by discrete low chloride spikes- the westernmost sites drilled on Hydrate Ridge show no freshening trend with depth. Strontium data reveal that all the me´lange samples contain deep fluids modified by reaction with the subducting oceanic crust. Thus we infer that, at the westernmost sites, accretion is too recent for the sediments to have undergone significant illitization. Our data demonstrate that a smooth decrease in dissolved chloride with depth cannot generally be used to infer the presence or to estimate the amount of gas hydrate in accretionary margins. Title: Relationship of pore water freshening to accretionary processes in the Cascadia margin: Fluid sources and gas hydrate abundance Author: Torres, Marta E., Tomaru, H., Teichert, B. M. A., Borowski, W., Tréhu, Anne Martine Drilling in the Cascadia accretionary complex enable us to evaluate the contribution of dehydration reactions and gas hydrate dissociation to pore water freshening. The observed freshening with depth and distance from the prism toe is consistent with enhanced conversion of smectite to illite, driven by increase in temperature and age of accreted sediments. Although they contain gas hydrate -as evidenced by discrete low chloride spikes- the westernmost sites drilled on Hydrate Ridge show no freshening trend with depth. Strontium data reveal that all the me´lange samples contain deep fluids modified by reaction with the subducting oceanic crust. Thus we infer that, at the westernmost sites, accretion is too recent for the sediments to have undergone significant illitization. Our data demonstrate that a smooth decrease in dissolved chloride with depth cannot generally be used to infer the presence or to estimate the amount of gas hydrate in accretionary margins. Close

• 412. [Article] Contribution of primary aerosol emissions from vegetation-derived sources to fine particle concentrations in Los Angeles

  Field measurements of the n-alkanes present in fine atomospheric aerosols show a predominance of odd carbon numbered higher molecular weight homologues (C27–C33) that is characteristic of plant waxes. ...

  Citation × Citation Citation Abstract Copy Title: Contribution of primary aerosol emissions from vegetation-derived sources to fine particle concentrations in Los Angeles Author: Rogge, Wolfgang F., Hildemann, Lynn M., Cass, Glen R., Simoneit, Bernd R. T., Mazurek, Monica A. Field measurements of the n-alkanes present in fine atomospheric aerosols show a predominance of odd carbon numbered higher molecular weight homologues (C27–C33) that is characteristic of plant waxes. Utilizing a local leaf wax n-alkane profile in conjunction with an air quality model, it is estimated that, at most, 0.2–1.0 µg m–3 of the airborne fine particulate matter (dp < 2.1 µm) present in the Los Angeles basin could originate from urban vegetative detritus; this corresponds to approximately 1–3% of the total ambient fine aerosol burden. However, some of the observed vegetation aerosol fingerprint in the Los Angeles air may be due in part to emission from food cooking rather than plant detritus. Seasonal trends in the ambient n-alkane patterns are examined to seek further insight into the relative importance of anthropogenic versus natural sources of vegetation-derived fine particulate matter. Title: Contribution of primary aerosol emissions from vegetation-derived sources to fine particle concentrations in Los Angeles Author: Rogge, Wolfgang F., Hildemann, Lynn M., Cass, Glen R., Simoneit, Bernd R. T., Mazurek, Monica A. Field measurements of the n-alkanes present in fine atomospheric aerosols show a predominance of odd carbon numbered higher molecular weight homologues (C27–C33) that is characteristic of plant waxes. Utilizing a local leaf wax n-alkane profile in conjunction with an air quality model, it is estimated that, at most, 0.2–1.0 µg m–3 of the airborne fine particulate matter (dp < 2.1 µm) present in the Los Angeles basin could originate from urban vegetative detritus; this corresponds to approximately 1–3% of the total ambient fine aerosol burden. However, some of the observed vegetation aerosol fingerprint in the Los Angeles air may be due in part to emission from food cooking rather than plant detritus. Seasonal trends in the ambient n-alkane patterns are examined to seek further insight into the relative importance of anthropogenic versus natural sources of vegetation-derived fine particulate matter. Close

• 413. [Article] A Decade of Ground–Air Temperature Tracking at Emigrant Pass Observatory, Utah

  Observations of air and ground temperatures collected between 1993 and 2004 from Emigrant Pass Geothermal Climate Observatory in northwestern Utah are analyzed to understand the relationship between these ...

  Citation × Citation Citation Abstract Copy Title: A Decade of Ground–Air Temperature Tracking at Emigrant Pass Observatory, Utah Author: Bartlett, Marshall G., Chapman, David S., Harris, Robert N. Observations of air and ground temperatures collected between 1993 and 2004 from Emigrant Pass Geothermal Climate Observatory in northwestern Utah are analyzed to understand the relationship between these two quantities. The influence of surface air temperature (SAT), incident solar radiation, and snow cover on surface ground temperature (SGT) variations are explored. SAT variations explain 94% of the variance in SGT. Incident solar radiation is the primary variable governing the remaining variance misfit and is significantly more important during summer months than winter months. A linear relationship between the ground–air temperature difference (ΔT[subscript]sgt-sat) and solar radiation exists with a trend of 1.21 K/(100 W m⁻²); solar radiation accounts for 1.3% of the variance in SGT. The effects of incident solar radiation also account for the 2.47-K average offset in ΔT[subscript]sgt-sat. During the winter, snow cover plays a role in governing SGT variability, but exerts only a minor influence on the annual tracking of ground and air temperatures at the site, accounting for 0.5% of the variance in SGT. These observations of the tracking of SGT and SAT confirm that borehole temperature changes mimic changes in SAT at frequencies appropriate for climatic reconstructions. Title: A Decade of Ground–Air Temperature Tracking at Emigrant Pass Observatory, Utah Author: Bartlett, Marshall G., Chapman, David S., Harris, Robert N. Observations of air and ground temperatures collected between 1993 and 2004 from Emigrant Pass Geothermal Climate Observatory in northwestern Utah are analyzed to understand the relationship between these two quantities. The influence of surface air temperature (SAT), incident solar radiation, and snow cover on surface ground temperature (SGT) variations are explored. SAT variations explain 94% of the variance in SGT. Incident solar radiation is the primary variable governing the remaining variance misfit and is significantly more important during summer months than winter months. A linear relationship between the ground–air temperature difference (ΔT[subscript]sgt-sat) and solar radiation exists with a trend of 1.21 K/(100 W m⁻²); solar radiation accounts for 1.3% of the variance in SGT. The effects of incident solar radiation also account for the 2.47-K average offset in ΔT[subscript]sgt-sat. During the winter, snow cover plays a role in governing SGT variability, but exerts only a minor influence on the annual tracking of ground and air temperatures at the site, accounting for 0.5% of the variance in SGT. These observations of the tracking of SGT and SAT confirm that borehole temperature changes mimic changes in SAT at frequencies appropriate for climatic reconstructions. Close

• 414. [Article] Dissolved organic carbon in interstitial waters from sediments of Middle Valley, leg 139

  High-temperature combustion oxidation measurements of nonvolatile dissolved organic carbon (DOC) have been determined for pore waters from sediments of Middle Valley, Ocean Drilling Program Leg 139, as ...

  Citation × Citation Citation Abstract Copy Title: Dissolved organic carbon in interstitial waters from sediments of Middle Valley, leg 139 Author: Ran, Baiyun, Simoneit, Bernd R. T. High-temperature combustion oxidation measurements of nonvolatile dissolved organic carbon (DOC) have been determined for pore waters from sediments of Middle Valley, Ocean Drilling Program Leg 139, as well as for overlying and near-bottom seawater. The DOC values in the interstitial waters are generally greater than those in the overlying water column, ranging from 0.1 to 86 mg/L of carbon. Some of the profiles of DOC in the pore waters are similar to total organic carbon, total carbon, and total inorganic carbon profiles. At Site 855 the concentrations of DOC in interstitial waters generally decrease with depth. DOC maxima at shallow depths of Site 858 are probably enriched due to higher temperature alteration of organic matter. At Sites 856 and 857, besides the decreasing trend above, the DOC increases at greater depths, also due to the hydrothermal activity. The values of DOC correlate with MnO and MgO profiles in Hole 856B. The changes below 30 mbsf in the DOC depth profiles of Site 858 parallel those of the volatile hydrocarbon gases. Title: Dissolved organic carbon in interstitial waters from sediments of Middle Valley, leg 139 Author: Ran, Baiyun, Simoneit, Bernd R. T. High-temperature combustion oxidation measurements of nonvolatile dissolved organic carbon (DOC) have been determined for pore waters from sediments of Middle Valley, Ocean Drilling Program Leg 139, as well as for overlying and near-bottom seawater. The DOC values in the interstitial waters are generally greater than those in the overlying water column, ranging from 0.1 to 86 mg/L of carbon. Some of the profiles of DOC in the pore waters are similar to total organic carbon, total carbon, and total inorganic carbon profiles. At Site 855 the concentrations of DOC in interstitial waters generally decrease with depth. DOC maxima at shallow depths of Site 858 are probably enriched due to higher temperature alteration of organic matter. At Sites 856 and 857, besides the decreasing trend above, the DOC increases at greater depths, also due to the hydrothermal activity. The values of DOC correlate with MnO and MgO profiles in Hole 856B. The changes below 30 mbsf in the DOC depth profiles of Site 858 parallel those of the volatile hydrocarbon gases. Close

• 415. [Article] Observations of Polarity Reversal in Shoaling Nonlinear Internal Waves

  Observations off the New Jersey coast document the shoaling of three groups of nonlinear internal waves of depression over 35 km across the shelf. Each wave group experienced changing background conditions ...

  Citation × Citation Citation Abstract Copy Title: Observations of Polarity Reversal in Shoaling Nonlinear Internal Waves Author: Moum, J. N., Shroyer, E. L., Nash, J. D. Observations off the New Jersey coast document the shoaling of three groups of nonlinear internal waves of depression over 35 km across the shelf. Each wave group experienced changing background conditions along its shoreward transit. Despite different wave environments, a clear pattern emerges. Nearly symmetric waves propagating into shallow water develop an asymmetric shape; in the wave reference frame, the leading edge accelerates causing the front face to broaden while the trailing face remains steep. This trend continues until the front edge and face of the leading depression wave become unidentifiable and a near-bottom elevation wave emerges, formed from the trailing face of the initial depression wave and the leading face of the following wave. The transition from depression to elevation waves is diagnosed by the integrated wave vorticity, which changes sign as the wave’s polarity changes sign. This transition is predicted by the sign change of the coefficient of the nonlinear term in the KdV equation, when evaluated using observed profiles of stratification and velocity. Title: Observations of Polarity Reversal in Shoaling Nonlinear Internal Waves Author: Moum, J. N., Shroyer, E. L., Nash, J. D. Observations off the New Jersey coast document the shoaling of three groups of nonlinear internal waves of depression over 35 km across the shelf. Each wave group experienced changing background conditions along its shoreward transit. Despite different wave environments, a clear pattern emerges. Nearly symmetric waves propagating into shallow water develop an asymmetric shape; in the wave reference frame, the leading edge accelerates causing the front face to broaden while the trailing face remains steep. This trend continues until the front edge and face of the leading depression wave become unidentifiable and a near-bottom elevation wave emerges, formed from the trailing face of the initial depression wave and the leading face of the following wave. The transition from depression to elevation waves is diagnosed by the integrated wave vorticity, which changes sign as the wave’s polarity changes sign. This transition is predicted by the sign change of the coefficient of the nonlinear term in the KdV equation, when evaluated using observed profiles of stratification and velocity. Close

• 416. [Article] Effect of packing fraction on ferromagnetic resonance in NiFe2O4 nanocomposites

  This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by American Institute of Physics and can be found at: http://www.aip.org/.

  Citation × Citation Citation Abstract Copy Title: Effect of packing fraction on ferromagnetic resonance in NiFe2O4 nanocomposites Author: Song, Han, Yokochi, Alexandre, Dhagat, Pallavi, Coussens, Nathan, Mulley, Sam, Jander, Albrecht This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by American Institute of Physics and can be found at: http://www.aip.org/. Title: Effect of packing fraction on ferromagnetic resonance in NiFe2O4 nanocomposites Author: Song, Han, Yokochi, Alexandre, Dhagat, Pallavi, Coussens, Nathan, Mulley, Sam, Jander, Albrecht This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by American Institute of Physics and can be found at: http://www.aip.org/. Close

• 417. [Article] Swarm Verification Techniques

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. ©2012 IEEE. Personal use of this material is permitted. Permission from IEEE must ...

  Citation × Citation Citation Abstract Copy Title: Swarm Verification Techniques Author: Groce, Alex, Holzmann, Gerard J., Joshi, Rajeev To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. ©2012 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works. This is the publisher’s final pdf. The published article is copyrighted by IEEE Computer Society and can be found at: http://www.computer.org/portal/web/publications. Title: Swarm Verification Techniques Author: Groce, Alex, Holzmann, Gerard J., Joshi, Rajeev To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. ©2012 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works. This is the publisher’s final pdf. The published article is copyrighted by IEEE Computer Society and can be found at: http://www.computer.org/portal/web/publications. Close

• 418. [Article] Tracking website data-collection and privacy practices with the iWatch Web Crawler

  In this paper we introduce the iWatch web crawler, a tool designed to catalogue and analyze online data practices and the use of privacy related indicators and technologies. Our goal in developing iWatch ...

  Citation × Citation Citation Abstract Copy Title: Tracking website data-collection and privacy practices with the iWatch Web Crawler Author: Jensen, Carlos, Potts, Colin, Sarkar, Chandan, Jensen, Christian In this paper we introduce the iWatch web crawler, a tool designed to catalogue and analyze online data practices and the use of privacy related indicators and technologies. Our goal in developing iWatch was to make possible a new type of analysis of trends, the impact of legislation on practices, and geographic and social differences online. In this paper we present preliminary findings from two sets of data collected 15 months apart and analyzed with this tool. Our combined samples included more than 240,000 pages from over 24,000 domains and 47 different countries. In addition to providing useful and needed data on the state of online data practices, we show that iWatch is a promising approach to the study of the web ecosystem. Title: Tracking website data-collection and privacy practices with the iWatch Web Crawler Author: Jensen, Carlos, Potts, Colin, Sarkar, Chandan, Jensen, Christian In this paper we introduce the iWatch web crawler, a tool designed to catalogue and analyze online data practices and the use of privacy related indicators and technologies. Our goal in developing iWatch was to make possible a new type of analysis of trends, the impact of legislation on practices, and geographic and social differences online. In this paper we present preliminary findings from two sets of data collected 15 months apart and analyzed with this tool. Our combined samples included more than 240,000 pages from over 24,000 domains and 47 different countries. In addition to providing useful and needed data on the state of online data practices, we show that iWatch is a promising approach to the study of the web ecosystem. Close

• 419. [Article] Anaerobic metabolism in Lake Washington sediments

  A method of measuring the dehydrogenase activity of sediments at lOC was calibrated by direct microcalorimetry at the same temperature. Field measurements of dehydrogenase activity of sediments in Lake ...

  Citation × Citation Citation Abstract Copy Title: Anaerobic metabolism in Lake Washington sediments Author: Bhagwat, Ashok M., Pamatmat, Mario Macalalag, U.S. International Biological Program. Coniferous Forest Biome A method of measuring the dehydrogenase activity of sediments at lOC was calibrated by direct microcalorimetry at the same temperature. Field measurements of dehydrogenase activity of sediments in Lake Washington were converted to rates of metabolic heat release by means of the significant regression of dehydrogenase activity on metabolic heat release. Simultaneous field measurements at IOC of oxygen uptake by undistrubed sediment cores were coverted to rates of metabolic heat release by the factor 4.8 cal liberated per milliliter of oxygen consumed. Dehydrogenase activity varies from place to place and differs between layers of the same core. Although there is a general trend of decreasing activity with sediment depth, some subsurface layers have relatively high activity. Dehydrogenase activity, which was detected down to the deepest layers of the sediment cores, 21 to 31 cm, appears to be more a function of plankton remains than of total organic carbon in the sediment. The integrated metabolic heat release based on dehydrogenase activity of the entire core was invariably greater than the metabolic heat release calculated from the rates of oxygen uptake. Thus, it appears that the rate of total oxygen uptake by the sediment surface underestimates benthic community metabolism in the sediment column. Title: Anaerobic metabolism in Lake Washington sediments Author: Bhagwat, Ashok M., Pamatmat, Mario Macalalag, U.S. International Biological Program. Coniferous Forest Biome A method of measuring the dehydrogenase activity of sediments at lOC was calibrated by direct microcalorimetry at the same temperature. Field measurements of dehydrogenase activity of sediments in Lake Washington were converted to rates of metabolic heat release by means of the significant regression of dehydrogenase activity on metabolic heat release. Simultaneous field measurements at IOC of oxygen uptake by undistrubed sediment cores were coverted to rates of metabolic heat release by the factor 4.8 cal liberated per milliliter of oxygen consumed. Dehydrogenase activity varies from place to place and differs between layers of the same core. Although there is a general trend of decreasing activity with sediment depth, some subsurface layers have relatively high activity. Dehydrogenase activity, which was detected down to the deepest layers of the sediment cores, 21 to 31 cm, appears to be more a function of plankton remains than of total organic carbon in the sediment. The integrated metabolic heat release based on dehydrogenase activity of the entire core was invariably greater than the metabolic heat release calculated from the rates of oxygen uptake. Thus, it appears that the rate of total oxygen uptake by the sediment surface underestimates benthic community metabolism in the sediment column. Close

• 420. [Article] How Race Impacts Voter Participation: A Study

  What does race have to do with it? A study of racial conflict theory. Looking back at the 2012 Presidential election, it is important to re-evaluate who participates in a democratic process. It is necessary ...

  Citation × Citation Citation Abstract Copy Title: How Race Impacts Voter Participation: A Study Author: Dietz, Elizabeth What does race have to do with it? A study of racial conflict theory. Looking back at the 2012 Presidential election, it is important to re-evaluate who participates in a democratic process. It is necessary to observe voter participation by people of color in order to gain a more robust understanding of our democratic process. It is also essential to study how voting trends affect policies put in place by racially dominant elites, in order to better to serve these dominant elites. This begs the question; who typically votes? The research will use racial conflict theory to explore a possible correlation between race and voter participation for elections. In particular, this study will demonstrate how racially dominant groups, Caucasians, typically participate in the voting process more often than historically disenfranchised groups, like African Americans. The research will use the National Election Survey and compile data across all states for multiple elections. Title: How Race Impacts Voter Participation: A Study Author: Dietz, Elizabeth What does race have to do with it? A study of racial conflict theory. Looking back at the 2012 Presidential election, it is important to re-evaluate who participates in a democratic process. It is necessary to observe voter participation by people of color in order to gain a more robust understanding of our democratic process. It is also essential to study how voting trends affect policies put in place by racially dominant elites, in order to better to serve these dominant elites. This begs the question; who typically votes? The research will use racial conflict theory to explore a possible correlation between race and voter participation for elections. In particular, this study will demonstrate how racially dominant groups, Caucasians, typically participate in the voting process more often than historically disenfranchised groups, like African Americans. The research will use the National Election Survey and compile data across all states for multiple elections. Close