Search

Search Results

• 621. [Article] Socioeconomic Determinants of Health Disparities by Race and Ethnicity: The Mediating Role of Social, Psychological and Behavioral Factors

  Socioeconomic status (SES) is inversely related to health status. Disparities in health status among races and ethnic groups are partly attributable to differences in SES, but the indirect pathways by ...

  Citation × Citation Citation Abstract Copy Title: Socioeconomic Determinants of Health Disparities by Race and Ethnicity: The Mediating Role of Social, Psychological and Behavioral Factors Author: Melekin, Amanuel Zimam Year: 2017 Socioeconomic status (SES) is inversely related to health status. Disparities in health status among races and ethnic groups are partly attributable to differences in SES, but the indirect pathways by which SES may influence health status are not widely studied. Using the Health and Retirement Study (HRS) data, this dissertation examined the pathways by which SES, via social, psychological, and behavioral factors predicted physical impairment and overnight hospitalization, and asked whether these indirect relationships differed by race/ethnicity. The HRS is a nationally representative multistage area probability sample administered biennially to respondents over the age of 51 and their spouses. Data collected between 2002 and 2010, covering five waves of the original HRS cohort born between the years 1931and 1941, were used. Two analysis approaches, Structural Equation Modeling (SEM) and Reconstructability Analysis (RA), were used. Adjustments for the complex survey design were made in the SEM analysis, whereas, data were matched for the RA method using propensity scores. Results of the SEM analyses supported most of the hypothesized indirect relationships between SES variables and physical impairment via social and psychological factors, but the indirect effect of SES on physical impairment via behavioral factors was weak. Multiple group analyses of path equality using nested chi-square tests indicated that the indirect effect of SES on physical impairment status did not vary by race/ethnicity. Social, psychological and behavioral factors were weakly related to overnight hospitalization, and SES was not indirectly related to overnight hospitalization. While these results supported several hypothesized indirect relationships between SES variables and physical health status, the indirect effect sizes were small. However, because this study examined predictive paths across groups rather than compare mean differences, and because indirect effects are products of individual path coefficients, small effect sizes are not uncommon in mediation analysis. Moreover, over a lifetime, small effects may gradually add up increasing group differences in health status with greater benefits accruing to higher SES individuals via social and psychological factors, as observed in this study. The RA results showed that indirect relationships between SES and physical impairment were similar across races/ethnicities for identical variables with a few exceptions. In several cases, however, selected SES variables related to social and psychological variables were different for different groups. Cross-sectional indirect relationships were stronger than longitudinal indirect relationships. As in the SEM study, SES was not related to physical impairment via behavioral factors; and, across groups, SES was also not related to overnight hospitalization either directly or via social, psychological or behavioral factors. Variables predicting physical impairment exhibited differences across groups; these differences were detected because RA, unlike SEM, used disaggregated social, psychological and behavioral factors. Where predictive variables overlapped, the effects of identical independent variable (IV) states on physical impairment were similar across groups with a few exceptions. In summary, both the SEM and RA results indicated that SES was indirectly related to physical impairment via social and psychological factors, and results from both methods also showed that SES was not indirectly related to overnight hospitalization via these factors. SEM did not find that these indirect effects varied by race/ethnicity; RA found a few differences. Title: Socioeconomic Determinants of Health Disparities by Race and Ethnicity: The Mediating Role of Social, Psychological and Behavioral Factors Author: Melekin, Amanuel Zimam Year: 2017 Socioeconomic status (SES) is inversely related to health status. Disparities in health status among races and ethnic groups are partly attributable to differences in SES, but the indirect pathways by which SES may influence health status are not widely studied. Using the Health and Retirement Study (HRS) data, this dissertation examined the pathways by which SES, via social, psychological, and behavioral factors predicted physical impairment and overnight hospitalization, and asked whether these indirect relationships differed by race/ethnicity. The HRS is a nationally representative multistage area probability sample administered biennially to respondents over the age of 51 and their spouses. Data collected between 2002 and 2010, covering five waves of the original HRS cohort born between the years 1931and 1941, were used. Two analysis approaches, Structural Equation Modeling (SEM) and Reconstructability Analysis (RA), were used. Adjustments for the complex survey design were made in the SEM analysis, whereas, data were matched for the RA method using propensity scores. Results of the SEM analyses supported most of the hypothesized indirect relationships between SES variables and physical impairment via social and psychological factors, but the indirect effect of SES on physical impairment via behavioral factors was weak. Multiple group analyses of path equality using nested chi-square tests indicated that the indirect effect of SES on physical impairment status did not vary by race/ethnicity. Social, psychological and behavioral factors were weakly related to overnight hospitalization, and SES was not indirectly related to overnight hospitalization. While these results supported several hypothesized indirect relationships between SES variables and physical health status, the indirect effect sizes were small. However, because this study examined predictive paths across groups rather than compare mean differences, and because indirect effects are products of individual path coefficients, small effect sizes are not uncommon in mediation analysis. Moreover, over a lifetime, small effects may gradually add up increasing group differences in health status with greater benefits accruing to higher SES individuals via social and psychological factors, as observed in this study. The RA results showed that indirect relationships between SES and physical impairment were similar across races/ethnicities for identical variables with a few exceptions. In several cases, however, selected SES variables related to social and psychological variables were different for different groups. Cross-sectional indirect relationships were stronger than longitudinal indirect relationships. As in the SEM study, SES was not related to physical impairment via behavioral factors; and, across groups, SES was also not related to overnight hospitalization either directly or via social, psychological or behavioral factors. Variables predicting physical impairment exhibited differences across groups; these differences were detected because RA, unlike SEM, used disaggregated social, psychological and behavioral factors. Where predictive variables overlapped, the effects of identical independent variable (IV) states on physical impairment were similar across groups with a few exceptions. In summary, both the SEM and RA results indicated that SES was indirectly related to physical impairment via social and psychological factors, and results from both methods also showed that SES was not indirectly related to overnight hospitalization via these factors. SEM did not find that these indirect effects varied by race/ethnicity; RA found a few differences. Close

• 622. [Article] Constraining the Holocene Extent of the Northwest Meers Fault, Oklahoma Using High-Resolution Topography and Paleoseismic Trenching

  The Meers Fault (Oklahoma) is one of few seismogenic structures with Holocene surface expression in the stable continental region of North America. Only the ~37 km-long southeastern section of the ~55 ...

  Citation × Citation Citation Abstract Copy Title: Constraining the Holocene Extent of the Northwest Meers Fault, Oklahoma Using High-Resolution Topography and Paleoseismic Trenching Author: Hornsby, Kristofer Tyler Year: 2017 The Meers Fault (Oklahoma) is one of few seismogenic structures with Holocene surface expression in the stable continental region of North America. Only the ~37 km-long southeastern section of the ~55 km long Meers Fault is interpreted to be Holocene-active. The ~17 km-long northwestern section is considered to be Quaternary-active (pre-Holocene); however, its low-relief geomorphic expression and anthropogenic alteration have presented difficulties in evaluating the fault length and style of Holocene deformation. We reevaluate surface expression and earthquake timing of the northwestern portion of the Meers Fault to improve fault characterization, earthquake rupture models, and seismic hazard evaluations based on fault length. We use a combination of airborne lidar (0.5--2 m-resolution), historical aerial photos, and new balloon-based photogrammetric (Structure from Motion) topography (0.25--0.5 m-resolution) collected in this study to analyze and characterize the fault scarp and local fault zone geomorphology. In the northwest, complex surface deformation includes fault splays, a left step, subtle monoclinal warping, and a minor change in fault strike The fault is evident in the landscape as linear escarpments, incised channels on the up-thrown side of the scarp, and closed depressions on the downthrown side. I use topographic profiles, measured perpendicular to the fault scarp to show that the northwest scarp is characterized by decimeter surface offsets. Where the fault traverses the Post Oak Conglomerate the fault zone width rarely exceeds 25 m, in the Hennessey Shale I document an increase in fault zone width with deformation occurring over 20 m to 115 m. I further examined the northwest section of the fault in a paleoseismic excavation where weathered Permian Hennessey Shale and a ~1--2 m-thick veneer of Holocene alluvial deposits have been folded and warped during three surface-folding earthquakes. In an adjacent stream exposure these units are also faulted near the ground surface. Paleoearthquake age modeling (Oxcal) constrained by accelerated mass spectrometry (AMS) dating of detrital charcoal and optically stimulated luminescence (OSL) dating of sandy alluvial beds indicates two earthquakes occurred since ~6152-5550 cal. years BP and one possibly older event along the erosional unconformity along the Hennessey Shale bedrock. This analysis lengthens the Holocene extent of the Meers Fault by ~6 km, to ~43 km, and extends the paleoseismic record of the Meers Fault to ~9598 cal. years BP. These data will improve fault-rupture and earthquake recurrence models used for seismic hazard analysis of the Meers Fault. Title: Constraining the Holocene Extent of the Northwest Meers Fault, Oklahoma Using High-Resolution Topography and Paleoseismic Trenching Author: Hornsby, Kristofer Tyler Year: 2017 The Meers Fault (Oklahoma) is one of few seismogenic structures with Holocene surface expression in the stable continental region of North America. Only the ~37 km-long southeastern section of the ~55 km long Meers Fault is interpreted to be Holocene-active. The ~17 km-long northwestern section is considered to be Quaternary-active (pre-Holocene); however, its low-relief geomorphic expression and anthropogenic alteration have presented difficulties in evaluating the fault length and style of Holocene deformation. We reevaluate surface expression and earthquake timing of the northwestern portion of the Meers Fault to improve fault characterization, earthquake rupture models, and seismic hazard evaluations based on fault length. We use a combination of airborne lidar (0.5--2 m-resolution), historical aerial photos, and new balloon-based photogrammetric (Structure from Motion) topography (0.25--0.5 m-resolution) collected in this study to analyze and characterize the fault scarp and local fault zone geomorphology. In the northwest, complex surface deformation includes fault splays, a left step, subtle monoclinal warping, and a minor change in fault strike The fault is evident in the landscape as linear escarpments, incised channels on the up-thrown side of the scarp, and closed depressions on the downthrown side. I use topographic profiles, measured perpendicular to the fault scarp to show that the northwest scarp is characterized by decimeter surface offsets. Where the fault traverses the Post Oak Conglomerate the fault zone width rarely exceeds 25 m, in the Hennessey Shale I document an increase in fault zone width with deformation occurring over 20 m to 115 m. I further examined the northwest section of the fault in a paleoseismic excavation where weathered Permian Hennessey Shale and a ~1--2 m-thick veneer of Holocene alluvial deposits have been folded and warped during three surface-folding earthquakes. In an adjacent stream exposure these units are also faulted near the ground surface. Paleoearthquake age modeling (Oxcal) constrained by accelerated mass spectrometry (AMS) dating of detrital charcoal and optically stimulated luminescence (OSL) dating of sandy alluvial beds indicates two earthquakes occurred since ~6152-5550 cal. years BP and one possibly older event along the erosional unconformity along the Hennessey Shale bedrock. This analysis lengthens the Holocene extent of the Meers Fault by ~6 km, to ~43 km, and extends the paleoseismic record of the Meers Fault to ~9598 cal. years BP. These data will improve fault-rupture and earthquake recurrence models used for seismic hazard analysis of the Meers Fault. Close

• 623. [Article] Urban Impacts to Forest Productivity, Soil Quality, and Canopy Structure in Forest Park, Portland, Oregon

  Land use practices and exposure to low impact disturbances associated with an urban environment can alter forest structure and function. Past and ongoing research in Forest Park, a large urban forest in ...

  Citation × Citation Citation Abstract Copy Title: Urban Impacts to Forest Productivity, Soil Quality, and Canopy Structure in Forest Park, Portland, Oregon Author: Addessi, Andrew David Year: 2017 Land use practices and exposure to low impact disturbances associated with an urban environment can alter forest structure and function. Past and ongoing research in Forest Park, a large urban forest in Portland, Oregon, suggests that mature mixed Douglas-fir (Psuedotsuga meziesii)-hardwood stands in the more urban end of the park lack a shade-tolerant conifer understory composed of the late successional conifer tree species, such western hemlock (Tsuga heterophylla) and western red-cedar (Thuja plicata). 5-year plot remeasurement data that characterizes productivity and mortality patterns did not show a strong relationship to urban proximity. Plot productivity was generally consistent with values taken from studies of other similarly aged (~100 years old) Douglas-fir /Western Hemlock stands. Mortality was highest in rural plots, and was driven by large windthrow events to canopy trees. Soil organic matter, soil pH, and depth of organic horizon indicated a legacy of soil impact in urban areas most impacted by past intensive logging. The urban mature plot had higher mean soil pH at site (5.87, se: ±0.06) compared to a rural mature, and old growth reference sites located within the park. Although surface organic and A layer soil horizon depth was thinnest at the urban mature site, soil organic matter was not found to be significantly different across sites. Light detection and ranging ( LiDAR) data showed that old-growth plots and plots in the middle section of the park had the highest degree of canopy structure as measured by Rumple and standard deviation of point elevation. Measures of stand height showed OG plots and urban plots to have the tallest trees. Rural plots showed a high degree of variability in all LiDAR metrics, showing a wider range of stand height and complexity than urban and middle plots. These results suggest that past land-use and urban proximity affect plot level productivity, soil quality, and above-ground canopy structure in Forest Park. These results clarify how the lack of late-successional tree species might be most linked to differing histories of intensive logging activity within the park. Reduced old-growth legacy features (remnant seed trees, coarse woody debris) in plots with a clear history of aggressive clear-cuts has led to a reduction in regeneration of western hemlock and western red-cedar in the understory. Title: Urban Impacts to Forest Productivity, Soil Quality, and Canopy Structure in Forest Park, Portland, Oregon Author: Addessi, Andrew David Year: 2017 Land use practices and exposure to low impact disturbances associated with an urban environment can alter forest structure and function. Past and ongoing research in Forest Park, a large urban forest in Portland, Oregon, suggests that mature mixed Douglas-fir (Psuedotsuga meziesii)-hardwood stands in the more urban end of the park lack a shade-tolerant conifer understory composed of the late successional conifer tree species, such western hemlock (Tsuga heterophylla) and western red-cedar (Thuja plicata). 5-year plot remeasurement data that characterizes productivity and mortality patterns did not show a strong relationship to urban proximity. Plot productivity was generally consistent with values taken from studies of other similarly aged (~100 years old) Douglas-fir /Western Hemlock stands. Mortality was highest in rural plots, and was driven by large windthrow events to canopy trees. Soil organic matter, soil pH, and depth of organic horizon indicated a legacy of soil impact in urban areas most impacted by past intensive logging. The urban mature plot had higher mean soil pH at site (5.87, se: ±0.06) compared to a rural mature, and old growth reference sites located within the park. Although surface organic and A layer soil horizon depth was thinnest at the urban mature site, soil organic matter was not found to be significantly different across sites. Light detection and ranging ( LiDAR) data showed that old-growth plots and plots in the middle section of the park had the highest degree of canopy structure as measured by Rumple and standard deviation of point elevation. Measures of stand height showed OG plots and urban plots to have the tallest trees. Rural plots showed a high degree of variability in all LiDAR metrics, showing a wider range of stand height and complexity than urban and middle plots. These results suggest that past land-use and urban proximity affect plot level productivity, soil quality, and above-ground canopy structure in Forest Park. These results clarify how the lack of late-successional tree species might be most linked to differing histories of intensive logging activity within the park. Reduced old-growth legacy features (remnant seed trees, coarse woody debris) in plots with a clear history of aggressive clear-cuts has led to a reduction in regeneration of western hemlock and western red-cedar in the understory. Close

• 624. [Article] Field Mapping Investigation and Geochemical Analysis of Volcanic Units within the Dinner Creek Tuff Eruptive Center, Malheur County, Eastern Oregon

  The Dinner Creek Tuff is a mid-Miocene rhyolitic to dacitic ignimbrite, consisting of four cooling units with 40Ar/39Ar ages 16--15 Ma. Previous geologists have suspected that the source of the tuff is ...

  Citation × Citation Citation Abstract Copy Title: Field Mapping Investigation and Geochemical Analysis of Volcanic Units within the Dinner Creek Tuff Eruptive Center, Malheur County, Eastern Oregon Author: Cruz, Matthew Year: 2017 The Dinner Creek Tuff is a mid-Miocene rhyolitic to dacitic ignimbrite, consisting of four cooling units with 40Ar/39Ar ages 16--15 Ma. Previous geologists have suspected that the source of the tuff is located in northwestern Malheur County, eastern Oregon. This broad area is called the Dinner Creek Tuff Eruptive Center. This thesis summarizes field work, XRF/ICP-MS geochemistry, thin section petrography, and SEM feldspar analysis from the summers of 2015 and 2016. The main purpose of this study is to identify sources for the Dinner Creek Tuff units within the Dinner Creek Tuff Eruptive Center. The secondary purpose is to map lave flows that pre-date and post-date the Dinner Creek Tuff, and correlate them with regionally extensive volcanic units. Two volcanic centers related to the Dinner Creek Tuff were identified. The southern volcanic center, centered at Castle Rock, is a caldera and source of the Dinner Creek Tuff unit 1 (DIT1). Rheomorphic, densely welded DIT1 is over 300 m thick along the east side of Castle Rock. The northwestern margin of the caldera has been uplifted along faults, showing vertically foliated tuff dikes and associated mega-breccia deposits. Up to 200 m of incipiently welded tuffs, and fluvial volcanoclastic sediments were deposited on the caldera floor, which has been uplifted due to resurgence and regional extension, creating the complex structural relationships between the volcanic units. The northern volcanic center is located at Ironside Mountain, where densely welded rheomorphic Dinner Creek Tuff unit 2 (DIT2) is exposed in outcrops over 600 m thick. The top of the DIT2 consists of glassy, moderately welded tuff. Sources for the DIT2 are tuff dikes along the south and western flanks of Ironside Mountain. The thick deposits of DIT2 at Ironside Mountain indicate that the mountain is an uplifted caldera, herein named the Ironside Mountain caldera. Uplift may have been due to resurgence, but it is most likely due to normal faulting along the Border Fault, a major regional normal fault that strikes across the northern margin of the caldera. Pre-Dinner Creek Tuff lava flows occur throughout the study area, and can be correlated with the Strawberry Volcanics and the Basalt of Malheur Gorge. A distinct lava flow, herein called the Ring Butte trachy-basalt occurs within the center of the study area, and is distinct from regional lava flows. Following the eruptions of the Dinner Creek Tuff units 1 & 2, aphyric basaltic-andesite and icelandite intrude into, and overlie the intra-caldera tuffs and caldera floor sediments at both calderas. These aphyric lavas are similar in appearance and stratigraphic position with the regionally extensive Hunter Creek basalt. Porphyritic olivine basalt overlies the aphyric Hunter Creek basalt at the Castle Rock caldera. This porphyritic lava is similar in appearance and major/trace element geochemistry to the regional Tim's Peak basalt. Title: Field Mapping Investigation and Geochemical Analysis of Volcanic Units within the Dinner Creek Tuff Eruptive Center, Malheur County, Eastern Oregon Author: Cruz, Matthew Year: 2017 The Dinner Creek Tuff is a mid-Miocene rhyolitic to dacitic ignimbrite, consisting of four cooling units with 40Ar/39Ar ages 16--15 Ma. Previous geologists have suspected that the source of the tuff is located in northwestern Malheur County, eastern Oregon. This broad area is called the Dinner Creek Tuff Eruptive Center. This thesis summarizes field work, XRF/ICP-MS geochemistry, thin section petrography, and SEM feldspar analysis from the summers of 2015 and 2016. The main purpose of this study is to identify sources for the Dinner Creek Tuff units within the Dinner Creek Tuff Eruptive Center. The secondary purpose is to map lave flows that pre-date and post-date the Dinner Creek Tuff, and correlate them with regionally extensive volcanic units. Two volcanic centers related to the Dinner Creek Tuff were identified. The southern volcanic center, centered at Castle Rock, is a caldera and source of the Dinner Creek Tuff unit 1 (DIT1). Rheomorphic, densely welded DIT1 is over 300 m thick along the east side of Castle Rock. The northwestern margin of the caldera has been uplifted along faults, showing vertically foliated tuff dikes and associated mega-breccia deposits. Up to 200 m of incipiently welded tuffs, and fluvial volcanoclastic sediments were deposited on the caldera floor, which has been uplifted due to resurgence and regional extension, creating the complex structural relationships between the volcanic units. The northern volcanic center is located at Ironside Mountain, where densely welded rheomorphic Dinner Creek Tuff unit 2 (DIT2) is exposed in outcrops over 600 m thick. The top of the DIT2 consists of glassy, moderately welded tuff. Sources for the DIT2 are tuff dikes along the south and western flanks of Ironside Mountain. The thick deposits of DIT2 at Ironside Mountain indicate that the mountain is an uplifted caldera, herein named the Ironside Mountain caldera. Uplift may have been due to resurgence, but it is most likely due to normal faulting along the Border Fault, a major regional normal fault that strikes across the northern margin of the caldera. Pre-Dinner Creek Tuff lava flows occur throughout the study area, and can be correlated with the Strawberry Volcanics and the Basalt of Malheur Gorge. A distinct lava flow, herein called the Ring Butte trachy-basalt occurs within the center of the study area, and is distinct from regional lava flows. Following the eruptions of the Dinner Creek Tuff units 1 & 2, aphyric basaltic-andesite and icelandite intrude into, and overlie the intra-caldera tuffs and caldera floor sediments at both calderas. These aphyric lavas are similar in appearance and stratigraphic position with the regionally extensive Hunter Creek basalt. Porphyritic olivine basalt overlies the aphyric Hunter Creek basalt at the Castle Rock caldera. This porphyritic lava is similar in appearance and major/trace element geochemistry to the regional Tim's Peak basalt. Close

• 625. [Article] Report on the Workshop for Life Detection in Samples from Mars

  The question of whether there is or was life on Mars has been one of the most pivotal since Schiaparellis’ telescopic observations of the red planet. With the advent of the space age, this question can ...

  Citation × Citation Citation Abstract Copy Title: Report on the Workshop for Life Detection in Samples from Mars Author: Kminek, Gerhard, Conley, Catherine, Allen, Carlton C., Bartlett, Douglas H., Beaty, David W., Benning, Liane G., Bhartia, Rohit, Boston, Penelope J., Duchaine, Caroline, Farmer, Jack D., Flynn, George J., Glavin, Daniel P., Gorby, Yuri, Hallsworth, John E., Mogul, Rakesh, Moser, Duane, Price, P. Buford, Pukall, Ruediger, Fernandez-Remolar, David, Smith, Caroline L., Stedman, Kenneth M., Steele, Andrew, Stepanauskas, Ramunas, Sun, Henry, Vago, Jorge L., Voytek, Mary A., Weiss, Paul S., Westfall, Frances Year: 2014 The question of whether there is or was life on Mars has been one of the most pivotal since Schiaparellis’ telescopic observations of the red planet. With the advent of the space age, this question can be addressed directly by exploring the surface of Mars and by bringing samples to Earth for analysis. The latter, however, is not free of problems. Life can be found virtually everywhere on Earth. Hence the potential for contaminating the Mars samples and compromising their scientific integrity is not negligible. Conversely, if life is present in samples from Mars, this may represent a potential source of extraterrestrial biological contamination for Earth. A range of measures and policies, collectively termed ‘planetary protection’, are employed to minimise risks and thereby prevent undesirable consequences for the terrestrial biosphere. This report documents discussions and conclusions from a workshop held in 2012, which followed a public conference focused on current capabilities for performing life-detection studies on Mars samples. The workshop focused on the evaluation of Mars samples that would maximise scientific productivity and inform decision making in the context of planetary protection. Workshop participants developed a strong consensus that the same measurements could be employed to effectively inform both science and planetary protection, when applied in the context of two competing hypotheses: 1) that there is no detectable life in the samples; or 2) that there is martian life in the samples. Participants then outlined a sequence for sample processing and defined analytical methods that would test these hypotheses. They also identified critical developments to enable the analysis of samples from Mars. Title: Report on the Workshop for Life Detection in Samples from Mars Author: Kminek, Gerhard, Conley, Catherine, Allen, Carlton C., Bartlett, Douglas H., Beaty, David W., Benning, Liane G., Bhartia, Rohit, Boston, Penelope J., Duchaine, Caroline, Farmer, Jack D., Flynn, George J., Glavin, Daniel P., Gorby, Yuri, Hallsworth, John E., Mogul, Rakesh, Moser, Duane, Price, P. Buford, Pukall, Ruediger, Fernandez-Remolar, David, Smith, Caroline L., Stedman, Kenneth M., Steele, Andrew, Stepanauskas, Ramunas, Sun, Henry, Vago, Jorge L., Voytek, Mary A., Weiss, Paul S., Westfall, Frances Year: 2014 The question of whether there is or was life on Mars has been one of the most pivotal since Schiaparellis’ telescopic observations of the red planet. With the advent of the space age, this question can be addressed directly by exploring the surface of Mars and by bringing samples to Earth for analysis. The latter, however, is not free of problems. Life can be found virtually everywhere on Earth. Hence the potential for contaminating the Mars samples and compromising their scientific integrity is not negligible. Conversely, if life is present in samples from Mars, this may represent a potential source of extraterrestrial biological contamination for Earth. A range of measures and policies, collectively termed ‘planetary protection’, are employed to minimise risks and thereby prevent undesirable consequences for the terrestrial biosphere. This report documents discussions and conclusions from a workshop held in 2012, which followed a public conference focused on current capabilities for performing life-detection studies on Mars samples. The workshop focused on the evaluation of Mars samples that would maximise scientific productivity and inform decision making in the context of planetary protection. Workshop participants developed a strong consensus that the same measurements could be employed to effectively inform both science and planetary protection, when applied in the context of two competing hypotheses: 1) that there is no detectable life in the samples; or 2) that there is martian life in the samples. Participants then outlined a sequence for sample processing and defined analytical methods that would test these hypotheses. They also identified critical developments to enable the analysis of samples from Mars. Close

• 626. [Article] Durability Assessment of Recycled Concrete Aggregates for Use in New Concrete Phase II

  This Phase II investigation into the durability of new concrete incorporating recycled concrete aggregates (RCA) focused on several goals: 1) Provide corroboration of results obtained in Phase I for a ...

  Citation × Citation Citation Abstract Copy Title: Durability Assessment of Recycled Concrete Aggregates for Use in New Concrete Phase II Author: Ideker, Jason H., Adams, Matthew P., Tanner, Jennifer, Jones, Angela Year: 2014 This Phase II investigation into the durability of new concrete incorporating recycled concrete aggregates (RCA) focused on several goals: 1) Provide corroboration of results obtained in Phase I for a multi-laboratory study related to assessing alkali-silica reactivity (ASR) of RCA in accelerated laboratory tests; 2) Investigate the efficacy of mitigation methods to control ASR in concrete containing potentially reactive RCA; 3) Establish long-term data through placement of concrete blocks containing RCA in an outdoor exposure site in Laramie, WY; and 4) Survey state DOTs and other transportation agencies about their perceptions and usage of RCA ASR in concrete within their agency and how that may be improved through the use of a database tracking tool. From Phase II the following main conclusions were drawn: 1) The coefficient of variation limits in ASTM C 1260-07 do not apply to concrete mortar bars incorporating RCA. It is recommended that further testing, using different RCA and more laboratories (at least six), should be completed before a new standard for RCA and/or incorporation of RCA into the current ASTM C 1260 test may be allowed. 2) Generally, as the replacement level of RCA was reduced, the amount of SCM needed to control deleterious ASR also decreased for the RCA sources investigated in this study. 3) Ternary blends containing metakaolin resulted in the most significant decrease in expansions compared to the mixtures with no SCMs. The results of the transportation agency survey showed the following: 1) A vast majority of agencies believed that sustainability was important to their agency and that it was addressed in a clear and meaningful way. 2) A majority, 54%, of agencies believed they had specific guidance for the use of RCA in new concrete; however, only 15% believed that there was strong information from the federal level about the use of RCA in new construction. 3) Of all respondents, 77% indicated their agency was concerned about alkali-silica reaction in concrete in general for their agency. 4) The biggest barriers to using RCA were noted as concerns about quality, a lack of standards and specifications, and unclear guidance on the testing of RCA. 5) The biggest concerns specific to a source of RCA when considering it for use in new construction were increased shrinkage concerns, ASR and residual chlorides. 6) The most sought-after information about a potential RCA source when considering it for use were the existing condition of the RCA when it was taken out of service, the reason it was taken out of service, whether repairs were performed to the structural element taken out of service, and the age of the RCA. Phase I can be found here: http://archives.pdx.edu/ds/psu/16737 Title: Durability Assessment of Recycled Concrete Aggregates for Use in New Concrete Phase II Author: Ideker, Jason H., Adams, Matthew P., Tanner, Jennifer, Jones, Angela Year: 2014 This Phase II investigation into the durability of new concrete incorporating recycled concrete aggregates (RCA) focused on several goals: 1) Provide corroboration of results obtained in Phase I for a multi-laboratory study related to assessing alkali-silica reactivity (ASR) of RCA in accelerated laboratory tests; 2) Investigate the efficacy of mitigation methods to control ASR in concrete containing potentially reactive RCA; 3) Establish long-term data through placement of concrete blocks containing RCA in an outdoor exposure site in Laramie, WY; and 4) Survey state DOTs and other transportation agencies about their perceptions and usage of RCA ASR in concrete within their agency and how that may be improved through the use of a database tracking tool. From Phase II the following main conclusions were drawn: 1) The coefficient of variation limits in ASTM C 1260-07 do not apply to concrete mortar bars incorporating RCA. It is recommended that further testing, using different RCA and more laboratories (at least six), should be completed before a new standard for RCA and/or incorporation of RCA into the current ASTM C 1260 test may be allowed. 2) Generally, as the replacement level of RCA was reduced, the amount of SCM needed to control deleterious ASR also decreased for the RCA sources investigated in this study. 3) Ternary blends containing metakaolin resulted in the most significant decrease in expansions compared to the mixtures with no SCMs. The results of the transportation agency survey showed the following: 1) A vast majority of agencies believed that sustainability was important to their agency and that it was addressed in a clear and meaningful way. 2) A majority, 54%, of agencies believed they had specific guidance for the use of RCA in new concrete; however, only 15% believed that there was strong information from the federal level about the use of RCA in new construction. 3) Of all respondents, 77% indicated their agency was concerned about alkali-silica reaction in concrete in general for their agency. 4) The biggest barriers to using RCA were noted as concerns about quality, a lack of standards and specifications, and unclear guidance on the testing of RCA. 5) The biggest concerns specific to a source of RCA when considering it for use in new construction were increased shrinkage concerns, ASR and residual chlorides. 6) The most sought-after information about a potential RCA source when considering it for use were the existing condition of the RCA when it was taken out of service, the reason it was taken out of service, whether repairs were performed to the structural element taken out of service, and the age of the RCA. Phase I can be found here: http://archives.pdx.edu/ds/psu/16737 Close

• 627. [Article] Conceptualizing Risk and Effectiveness: A Qualitative Study of Women’s and Providers’ Perceptions of Nonsurgical Female Permanent Contraception

  Objective: Novel approaches to nonsurgical permanent contraception (NSPC) for women that are low cost and require no incision or hysteroscope/surgical equipment could improve access to, and the acceptability ...

  Citation × Citation Citation Abstract Copy Title: Conceptualizing Risk and Effectiveness: A Qualitative Study of Women’s and Providers’ Perceptions of Nonsurgical Female Permanent Contraception Author: Harrington, Elizabeth K., Gordon, Diane, Osgood-Roach, Isabel, Jensen, Jeffrey T., Aengst, Jennifer Year: 2015 Objective: Novel approaches to nonsurgical permanent contraception (NSPC) for women that are low cost and require no incision or hysteroscope/surgical equipment could improve access to, and the acceptability of permanent contraception (PC). To better understand opportunities and limitations for NSPC approaches, we examined women's and OB/GYN providers' perceptions of NSPC in Portland, OR. Study Design: Semi-structured, qualitative interviews were conducted with 40 women recruited from outpatient clinics with purposive sampling, and a focus group was conducted with 9 OB/GYNs in academic and community practice. Transcripts were coded and inductively analyzed with a grounded theory approach. Results: The majority of women identified as white (67%) or Latina (25%). They had a median age of 31.5, and median number of children was one. Perspectives on NSPC were closely aligned with women's general attitudes towards PC; over half were considering PC for themselves or partners in the future. Most respondents valued multiple aspects of a nonsurgical approach, with themes of minimizing recovery time, invasiveness, risk, and avoiding hormonal contraception. Many assumed NSPC would be less effective than surgery, however, and felt a confirmation test would be necessary regardless of the failure rate. Providers welcomed efforts to expand contraceptive choice with NSPC, but would require long-term safety and efficacy data before recommending, and voiced concerns that NSPC's potential relative ease of administration could undermine the inherent seriousness of choosing PC. Conclusions: Women’s and providers’ perceptions of NSPC hinged on the ways in which they conceptualized risk and effectiveness. While perceptions were generally favorable, confirmation of safety and effectiveness would be required for a new approach to be accepted. Implications: This hypothesis-generating study elucidates women’s and provider’s perspectives on new methods of NSPC, and contributes to understanding their perceptions of various types of risk. A technique to verify tubal occlusion would be needed for women and providers to accept NSPC. Title: Conceptualizing Risk and Effectiveness: A Qualitative Study of Women’s and Providers’ Perceptions of Nonsurgical Female Permanent Contraception Author: Harrington, Elizabeth K., Gordon, Diane, Osgood-Roach, Isabel, Jensen, Jeffrey T., Aengst, Jennifer Year: 2015 Objective: Novel approaches to nonsurgical permanent contraception (NSPC) for women that are low cost and require no incision or hysteroscope/surgical equipment could improve access to, and the acceptability of permanent contraception (PC). To better understand opportunities and limitations for NSPC approaches, we examined women's and OB/GYN providers' perceptions of NSPC in Portland, OR. Study Design: Semi-structured, qualitative interviews were conducted with 40 women recruited from outpatient clinics with purposive sampling, and a focus group was conducted with 9 OB/GYNs in academic and community practice. Transcripts were coded and inductively analyzed with a grounded theory approach. Results: The majority of women identified as white (67%) or Latina (25%). They had a median age of 31.5, and median number of children was one. Perspectives on NSPC were closely aligned with women's general attitudes towards PC; over half were considering PC for themselves or partners in the future. Most respondents valued multiple aspects of a nonsurgical approach, with themes of minimizing recovery time, invasiveness, risk, and avoiding hormonal contraception. Many assumed NSPC would be less effective than surgery, however, and felt a confirmation test would be necessary regardless of the failure rate. Providers welcomed efforts to expand contraceptive choice with NSPC, but would require long-term safety and efficacy data before recommending, and voiced concerns that NSPC's potential relative ease of administration could undermine the inherent seriousness of choosing PC. Conclusions: Women’s and providers’ perceptions of NSPC hinged on the ways in which they conceptualized risk and effectiveness. While perceptions were generally favorable, confirmation of safety and effectiveness would be required for a new approach to be accepted. Implications: This hypothesis-generating study elucidates women’s and provider’s perspectives on new methods of NSPC, and contributes to understanding their perceptions of various types of risk. A technique to verify tubal occlusion would be needed for women and providers to accept NSPC. Close

• 628. [Article] Exposure to Fine Particulate Matter during Pregnancy and Risk of Preterm Birth among Women in New Jersey, Ohio, and Pennsylvania, 2000–2005

  Background: Particulate matter < 2.5 micrometers in aerodynamic diameter (PM2.5) has been variably associated with preterm birth (PTB). Objective: We classified preterm births into four categories (20–27, ...

  Citation × Citation Citation Abstract Copy Title: Exposure to Fine Particulate Matter during Pregnancy and Risk of Preterm Birth among Women in New Jersey, Ohio, and Pennsylvania, 2000–2005 Author: Rappazzo, Kristen M., Daniels, Julie L., Messer, Lynne C., Poole, Charles, Lobdell, Danelle T. Year: 2014 Background: Particulate matter < 2.5 micrometers in aerodynamic diameter (PM2.5) has been variably associated with preterm birth (PTB). Objective: We classified preterm births into four categories (20–27, 28–31, 32–34, and 35–36 weeks completed gestation) and estimated risk differences (RD) for each category in association with a 1-µg/m3 increase in PM2.5 exposure during each week of gestation. Methods: We assembled a cohort of singleton pregnancies that completed at least 20 weeks of gestation during 2000-2005 using live birth certificate data from three states (Pennsylvania, Ohio, and New Jersey) (n = 1,940,213; 8% PTB). We estimated mean PM2.5 exposures for each week of gestation from monitor-corrected Community Multi-Scale Air Quality modeling data. RDs were estimated using modified Poisson linear regression, adjusted for maternal race/ethnicity, marital status, education, age, and ozone. Results: RD estimates varied by exposure window and outcome period. Average PM2.5 exposure during the fourth week of gestation was positively associated with all PTB outcomes, though magnitude varied by PTB category (e.g., for a 1-μg/m3 increase, RD = 11.8 (95% CI: -6, 29.2); RD = 46 (95% CI: 23.2, 68.9); RD = 61.1 (95% CI: 22.6, 99.7); and RD = 28.5 (95% CI: -39, 95.7) for preterm births during 20-27, 28-31, 32-34, and 35-36 weeks, respectively). Exposures during the week of birth and the two weeks before birth also were positively associated with all PTB categories. Conclusions: Exposures beginning around the time of implantation and near birth appeared to be more strongly associated with PTB than exposures during other time periods. Because particulate matter exposure is ubiquitous, evidence of effects of PM2.5 exposure on PTB, even if small in magnitudes, is cause for concern. Title: Exposure to Fine Particulate Matter during Pregnancy and Risk of Preterm Birth among Women in New Jersey, Ohio, and Pennsylvania, 2000–2005 Author: Rappazzo, Kristen M., Daniels, Julie L., Messer, Lynne C., Poole, Charles, Lobdell, Danelle T. Year: 2014 Background: Particulate matter < 2.5 micrometers in aerodynamic diameter (PM2.5) has been variably associated with preterm birth (PTB). Objective: We classified preterm births into four categories (20–27, 28–31, 32–34, and 35–36 weeks completed gestation) and estimated risk differences (RD) for each category in association with a 1-µg/m3 increase in PM2.5 exposure during each week of gestation. Methods: We assembled a cohort of singleton pregnancies that completed at least 20 weeks of gestation during 2000-2005 using live birth certificate data from three states (Pennsylvania, Ohio, and New Jersey) (n = 1,940,213; 8% PTB). We estimated mean PM2.5 exposures for each week of gestation from monitor-corrected Community Multi-Scale Air Quality modeling data. RDs were estimated using modified Poisson linear regression, adjusted for maternal race/ethnicity, marital status, education, age, and ozone. Results: RD estimates varied by exposure window and outcome period. Average PM2.5 exposure during the fourth week of gestation was positively associated with all PTB outcomes, though magnitude varied by PTB category (e.g., for a 1-μg/m3 increase, RD = 11.8 (95% CI: -6, 29.2); RD = 46 (95% CI: 23.2, 68.9); RD = 61.1 (95% CI: 22.6, 99.7); and RD = 28.5 (95% CI: -39, 95.7) for preterm births during 20-27, 28-31, 32-34, and 35-36 weeks, respectively). Exposures during the week of birth and the two weeks before birth also were positively associated with all PTB categories. Conclusions: Exposures beginning around the time of implantation and near birth appeared to be more strongly associated with PTB than exposures during other time periods. Because particulate matter exposure is ubiquitous, evidence of effects of PM2.5 exposure on PTB, even if small in magnitudes, is cause for concern. Close

• 629. [Article] The Relationship between Mindfulness and Burnout among Master of Social Work Students

  Social work students frequently endure elevated levels of prolonged stress and psychological affliction that might result in serious consequences, such as development of burnout. Some experts suggest that ...

  Citation × Citation Citation Abstract Copy Title: The Relationship between Mindfulness and Burnout among Master of Social Work Students Author: Piatkowska, Jolanta Maria Year: 2014 Social work students frequently endure elevated levels of prolonged stress and psychological affliction that might result in serious consequences, such as development of burnout. Some experts suggest that burnout originates in the exposure to chronic interpersonal stressors in the work environment. Yet, there is emerging evidence suggesting that mindfulness practice might be beneficial in alleviating stress. Thus, the purpose of this exploratory study was to examine the relationship between mindfulness and burnout among Master of Social Work students. Burnout, mindfulness, religiosity, spirituality and their potential relationship were discussed and related to previous scholarly literature. Specifically, this study focused on testing the hypothesis that current MSW students who demonstrate higher levels of mindfulness will report less burnout, regardless of the year in the MSW program and regardless of the years of practice in human services. In addition, the hypothesis that students currently involved in direct social work practice (either outside of the MSW program, in the MSW field placement, or both) experience higher levels of burnout than students not yet practicing was scrutinized. Moreover, the hypothesis that as students progress in their studies they will exhibit progressively more burnout was explored. Finally, one of this study's goals was to explore whether patterns/relationships between the religious and spiritual beliefs and practices predict burnout levels among Master of Social Work students. Participants were mostly non-Hispanic White females, with a mean age of 35, married (or in legally recognized unions), and first year students enrolled full-time in the Direct Human Services track. Two years was the most common length of their experience in human services. They came from the metropolitan Portland area (on-campus students) and other regions of Oregon (off-site students). The mindfulness of the participants was measured with the Five Facets Mindfulness Scale and the levels of their burnout with the Maslach Burnout Inventory. Study results indicated that the more mindful the MSW students were, the less burnout they reported experiencing. A large correlation of mindfulness to reduced burnout (p < .001) was found, a relationship that persisted when controlling for other significant variables through sequential regression analysis. However, neither year in the MSW program, length of practicing in human services, nor religious/spiritual affiliation and practices had any significant influence on burnout among participants. Given the results of this study demonstrated statistically significant relationships between mindfulness and burnout among social work students, it is recommended that appropriate training in mindfulness for the students (and social workers) affected by secondary trauma and burnout should be incorporated in social work education, either as a part of curricula, or in an extra-curricular training program. Title: The Relationship between Mindfulness and Burnout among Master of Social Work Students Author: Piatkowska, Jolanta Maria Year: 2014 Social work students frequently endure elevated levels of prolonged stress and psychological affliction that might result in serious consequences, such as development of burnout. Some experts suggest that burnout originates in the exposure to chronic interpersonal stressors in the work environment. Yet, there is emerging evidence suggesting that mindfulness practice might be beneficial in alleviating stress. Thus, the purpose of this exploratory study was to examine the relationship between mindfulness and burnout among Master of Social Work students. Burnout, mindfulness, religiosity, spirituality and their potential relationship were discussed and related to previous scholarly literature. Specifically, this study focused on testing the hypothesis that current MSW students who demonstrate higher levels of mindfulness will report less burnout, regardless of the year in the MSW program and regardless of the years of practice in human services. In addition, the hypothesis that students currently involved in direct social work practice (either outside of the MSW program, in the MSW field placement, or both) experience higher levels of burnout than students not yet practicing was scrutinized. Moreover, the hypothesis that as students progress in their studies they will exhibit progressively more burnout was explored. Finally, one of this study's goals was to explore whether patterns/relationships between the religious and spiritual beliefs and practices predict burnout levels among Master of Social Work students. Participants were mostly non-Hispanic White females, with a mean age of 35, married (or in legally recognized unions), and first year students enrolled full-time in the Direct Human Services track. Two years was the most common length of their experience in human services. They came from the metropolitan Portland area (on-campus students) and other regions of Oregon (off-site students). The mindfulness of the participants was measured with the Five Facets Mindfulness Scale and the levels of their burnout with the Maslach Burnout Inventory. Study results indicated that the more mindful the MSW students were, the less burnout they reported experiencing. A large correlation of mindfulness to reduced burnout (p < .001) was found, a relationship that persisted when controlling for other significant variables through sequential regression analysis. However, neither year in the MSW program, length of practicing in human services, nor religious/spiritual affiliation and practices had any significant influence on burnout among participants. Given the results of this study demonstrated statistically significant relationships between mindfulness and burnout among social work students, it is recommended that appropriate training in mindfulness for the students (and social workers) affected by secondary trauma and burnout should be incorporated in social work education, either as a part of curricula, or in an extra-curricular training program. Close

• 630. [Article] "Dangerous Subjects": James D. Saules and the Enforcement of the Color Line in Oregon

  In June of 1844, James D. Saules, a black sailor turned farmer living in Oregon's Willamette Valley, was arrested and convicted for allegedly inciting Indians to violence against a settler named Charles ...

  Citation × Citation Citation Abstract Copy Title: "Dangerous Subjects": James D. Saules and the Enforcement of the Color Line in Oregon Author: Coleman, Kenneth Robert Year: 2014 In June of 1844, James D. Saules, a black sailor turned farmer living in Oregon's Willamette Valley, was arrested and convicted for allegedly inciting Indians to violence against a settler named Charles E. Pickett. Three years earlier, Saules had deserted the United States Exploring Expedition, married a Chinookan woman, and started a freight business on the Columbia River. Less than two months following Saules' arrest, Oregon's Provisional Government passed its infamous "Lash Law," banning the immigration of free black people to the region. While the government repealed the law in 1845, Oregon passed a territorial black exclusion law in 1849 and included a black exclusion clause in its 1857 state constitution. Oregon's territorial delegate also convinced the U.S. Congress to exclude black people from the 1850 Donation Land Act. In each case, Oregon politicians suggested the legacy of the Saules case by stressing the need to prevent black men, particularly sailors, from coming to Oregon and collaborating with local indigenous groups to commit acts of violence against white settlers. This thesis explains the unusual persistence of black exclusion laws in Oregon by focusing on the life of Saules, both before and after white American settlers came to the region in large numbers. Black exclusion in Oregon was neither an anomalous byproduct of American expansion nor a means to prevent slavery from taking root in the region. Instead, racial exclusion was central to the land-centered settler colonial project in the Pacific Northwest. Prior to the Americanization of the Pacific Northwest, the region was home to a cosmopolitan and increasingly fluid culture that incorporated various local Native groups, exogenous fur industry workers, and missionaries. This was a milieu made possible by colonialism and the rise of merchant capitalism during the Age of Sail, a period which lasted from the sixteenth to the mid-nineteenth century. This was also likely a world very familiar to Saules, who had spent his entire adult life aboard ships and in various seaports. However, the American immigrants who began arriving in Oregon in the early 1840s sought to dismantle this multiethnic social order, privatize land, and create a homogenous settler society based on classical republican principles. And although Saules was born in the United States, American settlers, emboldened by a racialist ideology, denied most non-whites a place in their settler society. Furthermore, during the early decades of resettlement, white American settlers often felt vulnerable to attacks from the preexisting population. Therefore, many settlers viewed free black men like Saules, a worldly sailor with connections among Native people, as potential threats to the security of their nascent communities. Title: "Dangerous Subjects": James D. Saules and the Enforcement of the Color Line in Oregon Author: Coleman, Kenneth Robert Year: 2014 In June of 1844, James D. Saules, a black sailor turned farmer living in Oregon's Willamette Valley, was arrested and convicted for allegedly inciting Indians to violence against a settler named Charles E. Pickett. Three years earlier, Saules had deserted the United States Exploring Expedition, married a Chinookan woman, and started a freight business on the Columbia River. Less than two months following Saules' arrest, Oregon's Provisional Government passed its infamous "Lash Law," banning the immigration of free black people to the region. While the government repealed the law in 1845, Oregon passed a territorial black exclusion law in 1849 and included a black exclusion clause in its 1857 state constitution. Oregon's territorial delegate also convinced the U.S. Congress to exclude black people from the 1850 Donation Land Act. In each case, Oregon politicians suggested the legacy of the Saules case by stressing the need to prevent black men, particularly sailors, from coming to Oregon and collaborating with local indigenous groups to commit acts of violence against white settlers. This thesis explains the unusual persistence of black exclusion laws in Oregon by focusing on the life of Saules, both before and after white American settlers came to the region in large numbers. Black exclusion in Oregon was neither an anomalous byproduct of American expansion nor a means to prevent slavery from taking root in the region. Instead, racial exclusion was central to the land-centered settler colonial project in the Pacific Northwest. Prior to the Americanization of the Pacific Northwest, the region was home to a cosmopolitan and increasingly fluid culture that incorporated various local Native groups, exogenous fur industry workers, and missionaries. This was a milieu made possible by colonialism and the rise of merchant capitalism during the Age of Sail, a period which lasted from the sixteenth to the mid-nineteenth century. This was also likely a world very familiar to Saules, who had spent his entire adult life aboard ships and in various seaports. However, the American immigrants who began arriving in Oregon in the early 1840s sought to dismantle this multiethnic social order, privatize land, and create a homogenous settler society based on classical republican principles. And although Saules was born in the United States, American settlers, emboldened by a racialist ideology, denied most non-whites a place in their settler society. Furthermore, during the early decades of resettlement, white American settlers often felt vulnerable to attacks from the preexisting population. Therefore, many settlers viewed free black men like Saules, a worldly sailor with connections among Native people, as potential threats to the security of their nascent communities. Close