Science.gov

Sample records for ecological responses investigations

  1. 100 Areas CERCLA ecological investigations

    SciTech Connect

    Landeen, D.S.; Sackschewsky, M.R.; Weiss, S.

    1993-09-01

    This document reports the results of the field terrestrial ecological investigations conducted by Westinghouse Hanford Company during fiscal years 1991 and 1992 at operable units 100-FR-3, 100-HR-3, 100-NR-2, 100-KR-4, and 100-BC-5. The tasks reported here are part of the Remedial Investigations conducted in support of the Comprehensive Environmental Response, compensation, and Liability Act of 1980 studies for the 100 Areas. These ecological investigations provide (1) a description of the flora and fauna associated with the 100 Areas operable units, emphasizing potential pathways for contaminants and species that have been given special status under existing state and/or federal laws, and (2) an evaluation of existing concentrations of heavy metals and radionuclides in biota associated with the 100 Areas operable units.

  2. Ecological Investigations, Curriculum Guide.

    ERIC Educational Resources Information Center

    Washington City Board of Education, NC.

    Activities which stress ecological concepts make up the major portion of this curriculum guide. Designed as a 12 week mini-course for students in grades eight and nine, the guide first presents the course schedule, including time requirements, lists the ecological concepts to be studied, and correlates the concepts with the activities. Following…

  3. Responsibility for the Ecological Crisis

    ERIC Educational Resources Information Center

    Wright, Richard T.

    1970-01-01

    Critically analyzes the thesis of Christian responsibility for the ecological crisis and leads to its rejection. Present day environmental misuse results from greed, carelessness, and ignorance." Advocates ecological strategy of corrective action, with supplementary theological strategy" for church-influenced citizens. (AL)

  4. Linking stressors and ecological responses

    USGS Publications Warehouse

    Gentile, J.H.; Solomon, K.R.; Butcher, J.B.; Harrass, M.; Landis, W.G.; Power, M.; Rattner, B.A.; Warren-Hicks, W.J.; Wenger, R.; Foran, Jeffery A.; Ferenc, Susan A.

    1999-01-01

    To characterize risk, it is necessary to quantify the linkages and interactions between chemical, physical and biological stressors and endpoints in the conceptual framework for ecological risk assessment (ERA). This can present challenges in a multiple stressor analysis, and it will not always be possible to develop a quantitative stressor-response profile. This review commences with a conceptual representation of the problem of developing a linkage analysis for multiple stressors and responses. The remainder of the review surveys a variety of mathematical and statistical methods (e.g., ranking methods, matrix models, multivariate dose-response for mixtures, indices, visualization, simulation modeling and decision-oriented methods) for accomplishing the linkage analysis for multiple stressors. Describing the relationships between multiple stressors and ecological effects are critical components of 'effects assessment' in the ecological risk assessment framework.

  5. Altering Their Ecological Niche: Investigating the Response of Avian Migrants to Changes in Vegetation Phenology at Northern Latitudes

    NASA Astrophysics Data System (ADS)

    Budde, M. E.; Ward, D. H.; Ely, C. R.; Handel, C. M.; Hupp, J. W.

    2009-12-01

    The impacts of global climate change are expected to be most severe at high northern latitudes. There is now strong evidence to support the hypothesis that such changes have had dramatic effects on the phenology of spring vegetative growth in these areas. One aspect of this change that has not been thoroughly investigated is how these changes vary across habitats and whether sub-Arctic and Arctic avifauna have adapted to shifts in plant phenology by modifying the timing of migration and nesting. A recent study showed that certain bird species have experienced population decline due to the varied timing of seasonal events and points to the fact that the degree of risk facing migratory birds is not well quantified. Plant phenology is especially sensitive to annual variation in temperature and precipitation and is a major determinant of plant species distribution, making it a good indicator of climate change effects. Migratory birds are considered one of the most vulnerable groups to the impacts of climate change because climate affects bird movement and distribution through species-specific physiological tolerances and changes in food and habitat resources. In this study we analyze the evidence for long-term plant phenology changes across different biomes of Alaska using satellite remote sensing techniques. We correlate this variability with ground-based measurements of avian migration and breeding. Specifically, we try to determine if the timing of spring green-up is synchronized across breeding areas or whether the process has become fractured across intervening biomes, potentially disrupting the timing of migration and breeding, putting species at risk. Using satellite-based time series of Normalized Difference Vegetation Index (NDVI) data, we create spatially explicit maps of seasonal vegetation metrics and correlate those with the timing and distribution of avian migrant populations. Preliminary investigation focused on the last 10 year period (2000-2009) and

  6. Ecological response to global climatic change

    USGS Publications Warehouse

    Malanson, G.P.; Butler, D.R.; Walsh, S. J.; Janelle, Donald G.; Warf, Barney; Hansen, Kathy

    2004-01-01

    Climate change and ecological change go hand in hand. Because we value our ecological environment, any change has the potential to be a problem. Geographers have been drawn to this challenge, and have been successful in addressing it, because the primary ecological response to climate changes in the past — the waxing and waning of the great ice sheets over the past 2 million years – was the changing geographic range of the biota. Plants and animals changed their location. Geographers have been deeply involved in documenting the changing biota of the past, and today we are called upon to help assess the possible responses to ongoing and future climatic change and, thus, their impacts. Assessing the potential responses is important for policy makers to judge the outcomes of action or inaction and also sets the stage for preparation for and mitigation of change.

  7. Ecology, Ethics, and Responsibility in Family Therapy.

    ERIC Educational Resources Information Center

    Maddock, James W.

    1993-01-01

    Notes that working with marital and family problems complicates the concept of therapeutic responsibility. Discusses several societal contributors to ethical dilemmas in contemporary family therapy and summarizes an ecological framework for therapy on the basis of which a profile of the ethical family therapist is derived. (Author/NB)

  8. Developmental change in social responsibility during adolescence: An ecological perspective.

    PubMed

    Wray-Lake, Laura; Syvertsen, Amy K; Flanagan, Constance A

    2016-01-01

    Social responsibility can be defined as a set of prosocial values representing personal commitments to contribute to community and society. Little is known about developmental change-and predictors of that change-in social responsibility during adolescence. The present study used an accelerated longitudinal research design to investigate the developmental trajectory of social responsibility values and ecological assets across family, school, community, and peer settings that predict these values. Data come from a 3-year study of 3,683 U.S. adolescents enrolled in upper-level elementary, middle, and high schools in rural, semiurban, and urban communities. Social responsibility values significantly decreased from age 9 to 16 before leveling off in later adolescence. Family compassion messages and democratic climate, school solidarity, community connectedness, and trusted friendship, positively predicted within-person change in adolescents' social responsibility values. These findings held after accounting for other individual-level and demographic factors and provide support for the role of ecological assets in adolescents' social responsibility development. In addition, fair society beliefs and volunteer experience had positive between- and within-person associations with social responsibility values. The manuscript discusses theoretical and practical implications of the conclusion that declines in ecological assets may partly explain age-related declines in social responsibility values. (PsycINFO Database Record

  9. Developmental change in social responsibility during adolescence: An ecological perspective.

    PubMed

    Wray-Lake, Laura; Syvertsen, Amy K; Flanagan, Constance A

    2016-01-01

    Social responsibility can be defined as a set of prosocial values representing personal commitments to contribute to community and society. Little is known about developmental change-and predictors of that change-in social responsibility during adolescence. The present study used an accelerated longitudinal research design to investigate the developmental trajectory of social responsibility values and ecological assets across family, school, community, and peer settings that predict these values. Data come from a 3-year study of 3,683 U.S. adolescents enrolled in upper-level elementary, middle, and high schools in rural, semiurban, and urban communities. Social responsibility values significantly decreased from age 9 to 16 before leveling off in later adolescence. Family compassion messages and democratic climate, school solidarity, community connectedness, and trusted friendship, positively predicted within-person change in adolescents' social responsibility values. These findings held after accounting for other individual-level and demographic factors and provide support for the role of ecological assets in adolescents' social responsibility development. In addition, fair society beliefs and volunteer experience had positive between- and within-person associations with social responsibility values. The manuscript discusses theoretical and practical implications of the conclusion that declines in ecological assets may partly explain age-related declines in social responsibility values. (PsycINFO Database Record PMID:26619322

  10. Improving Ecological Response Monitoring of Environmental Flows

    NASA Astrophysics Data System (ADS)

    King, Alison J.; Gawne, Ben; Beesley, Leah; Koehn, John D.; Nielsen, Daryl L.; Price, Amina

    2015-05-01

    Environmental flows are now an important restoration technique in flow-degraded rivers, and with the increasing public scrutiny of their effectiveness and value, the importance of undertaking scientifically robust monitoring is now even more critical. Many existing environmental flow monitoring programs have poorly defined objectives, nonjustified indicator choices, weak experimental designs, poor statistical strength, and often focus on outcomes from a single event. These negative attributes make them difficult to learn from. We provide practical recommendations that aim to improve the performance, scientific robustness, and defensibility of environmental flow monitoring programs. We draw on the literature and knowledge gained from working with stakeholders and managers to design, implement, and monitor a range of environmental flow types. We recommend that (1) environmental flow monitoring programs should be implemented within an adaptive management framework; (2) objectives of environmental flow programs should be well defined, attainable, and based on an agreed conceptual understanding of the system; (3) program and intervention targets should be attainable, measurable, and inform program objectives; (4) intervention monitoring programs should improve our understanding of flow-ecological responses and related conceptual models; (5) indicator selection should be based on conceptual models, objectives, and prioritization approaches; (6) appropriate monitoring designs and statistical tools should be used to measure and determine ecological response; (7) responses should be measured within timeframes that are relevant to the indicator(s); (8) watering events should be treated as replicates of a larger experiment; (9) environmental flow outcomes should be reported using a standard suite of metadata. Incorporating these attributes into future monitoring programs should ensure their outcomes are transferable and measured with high scientific credibility.

  11. Improving ecological response monitoring of environmental flows.

    PubMed

    King, Alison J; Gawne, Ben; Beesley, Leah; Koehn, John D; Nielsen, Daryl L; Price, Amina

    2015-05-01

    Environmental flows are now an important restoration technique in flow-degraded rivers, and with the increasing public scrutiny of their effectiveness and value, the importance of undertaking scientifically robust monitoring is now even more critical. Many existing environmental flow monitoring programs have poorly defined objectives, nonjustified indicator choices, weak experimental designs, poor statistical strength, and often focus on outcomes from a single event. These negative attributes make them difficult to learn from. We provide practical recommendations that aim to improve the performance, scientific robustness, and defensibility of environmental flow monitoring programs. We draw on the literature and knowledge gained from working with stakeholders and managers to design, implement, and monitor a range of environmental flow types. We recommend that (1) environmental flow monitoring programs should be implemented within an adaptive management framework; (2) objectives of environmental flow programs should be well defined, attainable, and based on an agreed conceptual understanding of the system; (3) program and intervention targets should be attainable, measurable, and inform program objectives; (4) intervention monitoring programs should improve our understanding of flow-ecological responses and related conceptual models; (5) indicator selection should be based on conceptual models, objectives, and prioritization approaches; (6) appropriate monitoring designs and statistical tools should be used to measure and determine ecological response; (7) responses should be measured within timeframes that are relevant to the indicator(s); (8) watering events should be treated as replicates of a larger experiment; (9) environmental flow outcomes should be reported using a standard suite of metadata. Incorporating these attributes into future monitoring programs should ensure their outcomes are transferable and measured with high scientific credibility.

  12. Investigations in Marine Chemistry: Tide Pool Ecology.

    ERIC Educational Resources Information Center

    Schlenker, Richard M.

    Students investigated the salinity of tide pools at different levels in the intertidal zone. Data are analyzed collectively. Students graphed and discussed data. Included are suggestions for evaluation and further study. (Author)

  13. Fiscal year 1991 100 Areas CERCLA ecological investigations

    SciTech Connect

    Sackschewsky, M.R.; Landeen, D.S.

    1992-04-01

    This report discusses the status of the ecological investigations conducted by Westinghouse Hanford Company during Fiscal Year 1991. These ecological investigations provide a basic description of the flora and fauna that inhabit the operable units, emphasizing species that have been given special status under existing state and/or federal laws. The 1991 Westinghouse Hanford Company field investigations have concentrated on the following: (1) bird surveys, (2) mammal and insect surveys, (3) vegetation surveys, and (4) vegetation sampling. Work being conducted as part of the vegetation surveys includes a biological assessment of threatened and endangered plants, which is being prepared as a separate document. Similar ecological investigations will be conducted at 100- N, K, and F operable units in 1992.

  14. Ecological investigation of a hazardous waste site, Warner Robins, Georgia

    SciTech Connect

    Wade, M.C. ); Billig, P. )

    1993-01-01

    Zone 1, Robins Air Force Base, Georgia, has been designated a National Priorities List Site by the US Environmental Protection Agency. The Remedial Investigation for Zone 1 recommended a quantitative analysis of ecological risk. To accomplish this task a characterization of the bottomland hardwood forest ecosystem present on the base was required. This ecological characterization included the study of hydrology, aquatic and wildlife biology, and wetlands ecology where potential impacts were in question. In addition, a suitable reference area was studied. The hydrologic investigation consisted primarily of the installation of water level recorders and staff gauges, collection of surface water data, installation of piezometers and collection of groundwater data, and the collection of rainfall data. The aquatic biology investigation centered around the sampling of benthic macroinvertebrate communities, bioassay toxicity tests for surface water and sediment, fish sampling, aquatic macrophyte collection, macrophyte collection, and emergent and free-floating plant collection. The wildlife biology investigation focused on a breeding bird survey. The wetlands ecology investigation comprised the collection of soil and vegetation samples and using the Wetland Evaluation Technique (WET) to assess the functions and values of the wetlands present.

  15. Isotopic, Ecological and Technological Investigations of the Land Snail Record

    ERIC Educational Resources Information Center

    Faber, Meredith L.

    2012-01-01

    In the ever-evolving landscape of the natural world, change is the only constant. Investigating how life accommodates that change can provide valuable insights into the biological, ecological and geological history of our planet. The fossil record is replete with examples of organisms which failed to survive in the wake of ongoing environmental…

  16. Ecological investigations at the Pantex Plant Site, 1992

    SciTech Connect

    Cushing, C.E.; Mazaika, R.R.; Phillips, R.C.

    1993-09-01

    In 1992, Pantex requested that Pacific Northwest Laboratory (PNL) conduct a series of ecological surveys to provide baseline information for designing detailed ecological studies on the various ecosystems present at the Pantex plant site near Amarillo, Texas. To this end, PNL scientist and technicians visited the site at different times to conduct investigations and collect samples: July 6--13: birds, small mammals, general habitat assessment; August 10--14: wetland vegetation, birds, small mammals, Playa invertebrates; and September 7--11: birds, small mammals. This report presents the results of these three surveys.

  17. Ecological investigation of a hazardous waste site, Warner Robins, Georgia

    SciTech Connect

    Wade, M. ); Billig, P. )

    1993-01-01

    Landfill No. 4 and the sludge lagoon at Robins Air Force Base, Warner Robins, Georgia, were added to the United States Environmental Protection Agency (EPA) National Priorities List in 1987 because of highpotential for contaminant migration. Warner Robins is located approximately 90 miles southeast of Atlanta. In 1990 CH2M HILL conducted a Remedial Investigation at the base that recommended that further ecological assessment investigations be conducted (CH2M HILL 1990). The subject paper is the result of this recommendation. The ecological study was carried out by the Hazardous Waste Remedial Actions Program (HAZWRAP)Division of Martin Marietta Energy Systems, Inc., working jointly with its subcontractor CDM (CDM 1992a). The primary area of investigation (Zone 1) included the sludge lagoon, Landfill No. 4, the wetland area east of the landfill and west of Hannah Road (including two sewage treatment ponds), and the area between Hannah Road and Horse Creek (Fig. 1). The bottomland forest wetlands of Zone 1 extend from the landfill east to Horse Creek. Surface water and groundwater flow across Zone 1 is generally in an easterly direction toward Horse Creek. Horse Creek is a south-flowing tributary of the Ocmulgee River Floodplain. The objective of the study was to perform a quantitative analysis of ecological risk associated with the ecosystems present in Zone 1. This investigation was unique because the assessment was to be based upon many measurement endpoints resulting in both location-specific data and data that would assess the condition of the overall ecosystem. The study was segregated into five distinct field investigations: hydrology, surface water and sediment, aquatic biology, wetlands ecology, and wildlife biology.

  18. Ecological investigation of a hazardous waste site, Warner Robins, Georgia

    SciTech Connect

    Wade, M.; Billig, P.

    1993-05-01

    Landfill No. 4 and the sludge lagoon at Robins Air Force Base, Warner Robins, Georgia, were added to the United States Environmental Protection Agency (EPA) National Priorities List in 1987 because of highpotential for contaminant migration. Warner Robins is located approximately 90 miles southeast of Atlanta. In 1990 CH2M HILL conducted a Remedial Investigation at the base that recommended that further ecological assessment investigations be conducted (CH2M HILL 1990). The subject paper is the result of this recommendation. The ecological study was carried out by the Hazardous Waste Remedial Actions Program (HAZWRAP)Division of Martin Marietta Energy Systems, Inc., working jointly with its subcontractor CDM (CDM 1992a). The primary area of investigation (Zone 1) included the sludge lagoon, Landfill No. 4, the wetland area east of the landfill and west of Hannah Road (including two sewage treatment ponds), and the area between Hannah Road and Horse Creek (Fig. 1). The bottomland forest wetlands of Zone 1 extend from the landfill east to Horse Creek. Surface water and groundwater flow across Zone 1 is generally in an easterly direction toward Horse Creek. Horse Creek is a south-flowing tributary of the Ocmulgee River Floodplain. The objective of the study was to perform a quantitative analysis of ecological risk associated with the ecosystems present in Zone 1. This investigation was unique because the assessment was to be based upon many measurement endpoints resulting in both location-specific data and data that would assess the condition of the overall ecosystem. The study was segregated into five distinct field investigations: hydrology, surface water and sediment, aquatic biology, wetlands ecology, and wildlife biology.

  19. Ecological relevance of Sentinels' biomarker responses: a multi-level approach.

    PubMed

    Seabra Pereira, Camilo D; Abessa, Denis M S; Choueri, Rodrigo B; Almagro-Pastor, Victor; Cesar, Augusto; Maranho, Luciane A; Martín-Díaz, María Laura; Torres, Ronaldo J; Gusso-Choueri, Paloma K; Almeida, João E; Cortez, Fernando S; Mozeto, Antonio A; Silbiger, Helcy L N; Sousa, Eduinetty C P M; Del Valls, Tommas Angel; Bainy, Afonso C D

    2014-05-01

    In response to the need for more sensitive and rapid indicators of environmental quality, sublethal effects on the lowest levels of biological organization have been investigated. The ecological relevance of these responses assumes a prevailing role to assure effectiveness as indicator of ecological status. This study aimed to investigate the linkages between biomarker responses of caged bivalves and descriptive parameters of macrobenthic community structure. For this purpose a multi-level environmental assessment of marine and estuarine zones was performed in São Paulo coast, Brazil. Multivariate analysis was applied to identify linkages between biological responses and ecological indices, as well as to characterizing the studied stations. Individuals of the marine mussel Perna perna caged along Santos Bay showed signs of oxidative stress, lysosomal membrane destabilization, histological alterations and reduced embryonic development. The estuarine oyster Crassostrea rhizophorae caged along Santos Port Channel showed alterations on biotransformation enzymes and antioxidant system, DNA damage and lysosomal membrane destabilization. The benthic community analysis showed reduced richness and diversity in the same areas of the Santos bay and estuary where biomarker responses were altered. Our results revealed that xenobiotics are inducing physiological stress, which may lead to changes of the benthic community structure and deterioration of the ecological status over time. Integrating biomarker responses and ecological indexes improved certainty that alterations found at community level could be related to xenobiotic as stressors, which was very useful to improve the discriminatory power of the environmental assessment.

  20. Shrinking body size as an ecological response to climate change

    NASA Astrophysics Data System (ADS)

    Sheridan, Jennifer A.; Bickford, David

    2011-11-01

    Determining how climate change will affect global ecology and ecosystem services is one of the next important frontiers in environmental science. Many species already exhibit smaller sizes as a result of climate change and many others are likely to shrink in response to continued climate change, following fundamental ecological and metabolic rules. This could negatively impact both crop plants and protein sources such as fish that are important for human nutrition. Furthermore, heterogeneity in response is likely to upset ecosystem balances. We discuss future research directions to better understand the trend and help ameliorate the trophic cascades and loss of biodiversity that will probably result from continued decreases in organism size.

  1. Ecological risk assessment guidance for preparation of remedial investigation/feasibility study work plans

    SciTech Connect

    Pentecost, E.D.; Vinikour, W.S.

    1993-08-01

    This guidance document (1) provides instructions on preparing the components of an ecological work plan to complement the overall site remedial assessment investigation/feasibility study (RI/FS) work plan and (2) directs the user on how to implement ecological tasks identified in the plan. Under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA), as amended by the Superfired Amendments and Reauthorization Act of 1986 (SARA), an RI/FS work plan win have to be developed as part of the site-remediation scoping the process. Specific guidance on the RI/FS process and the preparation of work plans has been developed by the US Environmental Protection Agency (EPA 1988a). This document provides guidance to US Department of Energy (DOE) staff and contractor personnel for incorporation of ecological information into environmental remediation planning and decision making at CERCLA sites. An overview analysis of early ecological risk assessment methods (i.e., in the 1980s) at Superfund sites was conducted by the EPA (1989a). That review provided a perspective of attention given to ecological issues in some of the first RI/FS studies. By itself, that reference is of somewhat limited value; it does, however, establish a basis for comparison of past practices in ecological risk with current, more refined methods.

  2. Response Diversity and Resilience in Social-Ecological Systems.

    PubMed

    Leslie, Paul; McCabe, J Terrence

    2013-04-01

    Recent work in ecology suggests that the diversity of responses to environmental change among species contributing to the same ecosystem function can strongly influence ecosystem resilience. To render this important realization more useful for understanding coupled human-natural systems, we broaden the concept of response diversity to include heterogeneity in human decisions and action. Simply put, not all actors respond the same way to challenges, opportunities, and risks. The range, prevalence, and spatial and temporal distributions of different responses may be crucial to the resilience or the transformation of a social-ecological system, and thus have a bearing on human vulnerability and well-being in the face of environmental, socioeconomic, and political change. Response diversity can be seen at multiple scales (e.g., household, village, region) and response diversity at one scale may act synergistically with or contrary to the effects of diversity at another scale. Although considerable research on the sources of response diversity has been done, our argument is that the consequences of response diversity warrant closer attention. We illustrate this argument with examples drawn from our studies of two East African pastoral populations and discuss the relationship of response diversity to characteristics of social-ecological systems that can promote or diminish resilience.

  3. Response Diversity and Resilience in Social-Ecological Systems

    PubMed Central

    Leslie, Paul; McCabe, J. Terrence

    2013-01-01

    Recent work in ecology suggests that the diversity of responses to environmental change among species contributing to the same ecosystem function can strongly influence ecosystem resilience. To render this important realization more useful for understanding coupled human-natural systems, we broaden the concept of response diversity to include heterogeneity in human decisions and action. Simply put, not all actors respond the same way to challenges, opportunities, and risks. The range, prevalence, and spatial and temporal distributions of different responses may be crucial to the resilience or the transformation of a social-ecological system, and thus have a bearing on human vulnerability and well-being in the face of environmental, socioeconomic, and political change. Response diversity can be seen at multiple scales (e.g., household, village, region) and response diversity at one scale may act synergistically with or contrary to the effects of diversity at another scale. Although considerable research on the sources of response diversity has been done, our argument is that the consequences of response diversity warrant closer attention. We illustrate this argument with examples drawn from our studies of two East African pastoral populations and discuss the relationship of response diversity to characteristics of social-ecological systems that can promote or diminish resilience. PMID:24855324

  4. Incorporating ecological risk assessment into remedial investigation/feasibility study work plans

    SciTech Connect

    Not Available

    1994-06-01

    This guidance document (1) provides instructions on preparing the components of an ecological work plan to complement the overall site remedial investigation/feasibility study (RI/FS) work plan and (2) directs the user on how to implement ecological tasks identified in the plan. Under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA), as amended by the Superfund Amendments and Reauthorization Act of 1986 (SARA), and RI/FS work plan will have to be developed as part of the site-remediation scoping process. Specific guidance on the RI/FS process and the preparation of work plans has been developed by the US Environmental Protection Agency (EPA 1988a). This document provides guidance to US Department of Energy (DOE) staff and contractor personnel for incorporation of ecological information into environmental remediation planning and decision making at CERCLA sites.

  5. Remedial investigation report for J-Field, Aberdeen Proving Ground, Maryland. Volume 3: Ecological risk assessment

    SciTech Connect

    Hlohowskyj, I.; Hayse, J.; Kuperman, R.; Van Lonkhuyzen, R.

    2000-02-25

    The Environmental Management Division of the U.S. Army Aberdeen Proving Ground (APG), Maryland, is conducting a remedial investigation (RI) and feasibility study (FS) of the J-Field area at APG, pursuant to the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), as amended. As part of that activity, Argonne National Laboratory (ANL) conducted an ecological risk assessment (ERA) of the J-Field site. This report presents the results of that assessment.

  6. Designing the Perfect Plant: Activities to Investigate Plant Ecology

    ERIC Educational Resources Information Center

    Lehnhoff, Erik; Woolbaugh, Walt; Rew, Lisa

    2008-01-01

    Plant ecology is an important subject that often receives little attention in middle school, as more time during science classes is devoted to plant biology. Therefore, the authors have developed a series of activities, including a card game--Designing the Perfect Plant--to introduce student's to plant ecology and the ecological trade offs…

  7. Investigating Cooperative Behavior in Ecological Settings: An EEG Hyperscanning Study

    PubMed Central

    Petti, Manuela; He, Eric J.; De Giusti, Vittorio; He, Bin; Astolfi, Laura; Babiloni, Fabio

    2016-01-01

    The coordinated interactions between individuals are fundamental for the success of the activities in some professional categories. We reported on brain-to-brain cooperative interactions between civil pilots during a simulated flight. We demonstrated for the first time how the combination of neuroelectrical hyperscanning and intersubject connectivity could provide indicators sensitive to the humans’ degree of synchronization under a highly demanding task performed in an ecological environment. Our results showed how intersubject connectivity was able to i) characterize the degree of cooperation between pilots in different phases of the flight, and ii) to highlight the role of specific brain macro areas in cooperative behavior. During the most cooperative flight phases pilots showed, in fact, dense patterns of interbrain connectivity, mainly linking frontal and parietal brain areas. On the contrary, the amount of interbrain connections went close to zero in the non-cooperative phase. The reliability of the interbrain connectivity patterns was verified by means of a baseline condition represented by formal couples, i.e. pilots paired offline for the connectivity analysis but not simultaneously recorded during the flight. Interbrain density was, in fact, significantly higher in real couples with respect to formal couples in the cooperative flight phases. All the achieved results demonstrated how the description of brain networks at the basis of cooperation could effectively benefit from a hyperscanning approach. Interbrain connectivity was, in fact, more informative in the investigation of cooperative behavior with respect to established EEG signal processing methodologies applied at a single subject level. PMID:27124558

  8. Investigating Cooperative Behavior in Ecological Settings: An EEG Hyperscanning Study.

    PubMed

    Toppi, Jlenia; Borghini, Gianluca; Petti, Manuela; He, Eric J; De Giusti, Vittorio; He, Bin; Astolfi, Laura; Babiloni, Fabio

    2016-01-01

    The coordinated interactions between individuals are fundamental for the success of the activities in some professional categories. We reported on brain-to-brain cooperative interactions between civil pilots during a simulated flight. We demonstrated for the first time how the combination of neuroelectrical hyperscanning and intersubject connectivity could provide indicators sensitive to the humans' degree of synchronization under a highly demanding task performed in an ecological environment. Our results showed how intersubject connectivity was able to i) characterize the degree of cooperation between pilots in different phases of the flight, and ii) to highlight the role of specific brain macro areas in cooperative behavior. During the most cooperative flight phases pilots showed, in fact, dense patterns of interbrain connectivity, mainly linking frontal and parietal brain areas. On the contrary, the amount of interbrain connections went close to zero in the non-cooperative phase. The reliability of the interbrain connectivity patterns was verified by means of a baseline condition represented by formal couples, i.e. pilots paired offline for the connectivity analysis but not simultaneously recorded during the flight. Interbrain density was, in fact, significantly higher in real couples with respect to formal couples in the cooperative flight phases. All the achieved results demonstrated how the description of brain networks at the basis of cooperation could effectively benefit from a hyperscanning approach. Interbrain connectivity was, in fact, more informative in the investigation of cooperative behavior with respect to established EEG signal processing methodologies applied at a single subject level.

  9. Biofilm Formation As a Response to Ecological Competition

    PubMed Central

    Oliveira, Nuno M.; Martinez-Garcia, Esteban; Xavier, Joao; Durham, William M.; Kolter, Roberto; Kim, Wook; Foster, Kevin R.

    2015-01-01

    Bacteria form dense surface-associated communities known as biofilms that are central to their persistence and how they affect us. Biofilm formation is commonly viewed as a cooperative enterprise, where strains and species work together for a common goal. Here we explore an alternative model: biofilm formation is a response to ecological competition. We co-cultured a diverse collection of natural isolates of the opportunistic pathogen Pseudomonas aeruginosa and studied the effect on biofilm formation. We show that strain mixing reliably increases biofilm formation compared to unmixed conditions. Importantly, strain mixing leads to strong competition: one strain dominates and largely excludes the other from the biofilm. Furthermore, we show that pyocins, narrow-spectrum antibiotics made by other P. aeruginosa strains, can stimulate biofilm formation by increasing the attachment of cells. Side-by-side comparisons using microfluidic assays suggest that the increase in biofilm occurs due to a general response to cellular damage: a comparable biofilm response occurs for pyocins that disrupt membranes as for commercial antibiotics that damage DNA, inhibit protein synthesis or transcription. Our data show that bacteria increase biofilm formation in response to ecological competition that is detected by antibiotic stress. This is inconsistent with the idea that sub-lethal concentrations of antibiotics are cooperative signals that coordinate microbial communities, as is often concluded. Instead, our work is consistent with competition sensing where low-levels of antibiotics are used to detect and respond to the competing genotypes that produce them. PMID:26158271

  10. Key ecological responses to nitrogen are altered by climate change

    USGS Publications Warehouse

    Greaver, T.L.; Clark, C.M.; Compton, J.E.; Vallano, D.; Talhelm, A. F.; Weaver, C.P.; Band, L.E.; Baron, J. S.; Davidson, E.A.; Tague, C.L.; Felker-Quinn, E.; Lynch, J.A.; Herrick, J.D.; Liu, L.; Goodale, C.L.; Novak, K. J.; Haeuber, R. A.

    2016-01-01

    Climate change and anthropogenic nitrogen deposition are both important ecological threats. Evaluating their cumulative effects provides a more holistic view of ecosystem vulnerability to human activities, which would better inform policy decisions aimed to protect the sustainability of ecosystems. Our knowledge of the cumulative effects of these stressors is growing, but we lack an integrated understanding. In this Review, we describe how climate change alters key processes in terrestrial and freshwater ecosystems related to nitrogen cycling and availability, and the response of ecosystems to nitrogen addition in terms of carbon cycling, acidification and biodiversity.

  11. Key ecological responses to nitrogen are altered by climate change

    NASA Astrophysics Data System (ADS)

    Greaver, T. L.; Clark, C. M.; Compton, J. E.; Vallano, D.; Talhelm, A. F.; Weaver, C. P.; Band, L. E.; Baron, J. S.; Davidson, E. A.; Tague, C. L.; Felker-Quinn, E.; Lynch, J. A.; Herrick, J. D.; Liu, L.; Goodale, C. L.; Novak, K. J.; Haeuber, R. A.

    2016-09-01

    Climate change and anthropogenic nitrogen deposition are both important ecological threats. Evaluating their cumulative effects provides a more holistic view of ecosystem vulnerability to human activities, which would better inform policy decisions aimed to protect the sustainability of ecosystems. Our knowledge of the cumulative effects of these stressors is growing, but we lack an integrated understanding. In this Review, we describe how climate change alters key processes in terrestrial and freshwater ecosystems related to nitrogen cycling and availability, and the response of ecosystems to nitrogen addition in terms of carbon cycling, acidification and biodiversity.

  12. Ecological Responses to the 1980 Eruption of Mount St. Helens

    NASA Astrophysics Data System (ADS)

    Dale, Virginia H.; Swanson, Frederick J.; Crisafulli, Charles M.

    The eruption of Mount St. Helens on May 18, 1980, had a momentous impact on the fungal, plant, animal, and human life from the mountain to the far reaches of the explosion's ash cloud and mudflows. Although this intense natural event caused loss of substantial life and property, it also created a unique opportunity to examine a huge disturbance of natural systems and their subsequent responses. Based on one of the most studied areas of volcanic activity, this book synthesizes the ecological research that has been conducted for twenty-five years since the eruption.

  13. Study on the Change of Landscape and Ecology of Sitou Forestland by Using Remotely Sensed and Ecological Investigation Data

    NASA Astrophysics Data System (ADS)

    Wei, Chiang; Lee, Chin-Ling; Liao, Huan-Chang; Tien, Pei-Ling; Huang, Yi-Ru; Tseng, Yu-San; Lai, Jing Rong; Shen, Chieh-Wen

    Due to natural disasters and anthropogenic disturbances in recent years, the landscape in Central Taiwan suffered certain kind of changes. In particular, landslides caused by earthquake and heavy rainfall, improper use and development in slope land enlarge and speed up the change of forest landscape. Few studies were focused on the interactions and relationships between change of ecosystem and landscape in Taiwan after natural disturbances in recent years. In this study, a pioneering research is accomplished by using Landscape Indices (LI) derived from FORMOSAT II Satellite imagery and GIS spatial coverage to describe the possible pattern of change between landscape and ecology. Located at the mountainous area in central Taiwan, ranging from 800 to 1,800 meter and comprising 2,349 hectares in size, Sitou Tract of the National Taiwan University Experimental Forest is selected as the study site. Four satellite images through 2004 to 2007 are used to compute LI, and analyzed with ecological investigation collected from five ground sites. The preliminary result shows that by using remotely sensed data and ground investigation, it is feasible to monitor and assess the relationship between change of landscape and ecology in forests. It indicates that the recovery and restoration of vegetation after the human and natural disturbances highly correlates with the value of NDVI (Normalized Differential Vegetation Index), the composition and diversity of birds and insects are highly correlated with the diversity of patches. The values of SHDI (Shannon Diversity Index), SIDI (Simpson Diversity Index), SHEI (Shannon Evenness Index) and SIEI (Simpson Evenness Index) show that the diversity of landscape is growing while the evenness of landscape remains stable between 2004 and 2007. The ecological investigation in 2006 and 2007 indicated that the species and relative abundance is decreasing. The proof for the obvious relationship between the change of ecology and landscape metrics

  14. Developmental Change in Social Responsibility during Adolescence: An Ecological Perspective

    ERIC Educational Resources Information Center

    Wray-Lake, Laura; Syvertsen, Amy K.; Flanagan, Constance A.

    2016-01-01

    Social responsibility can be defined as a set of prosocial values representing personal commitments to contribute to community and society. Little is known about developmental change--and predictors of that change--in social responsibility during adolescence. The present study used an accelerated longitudinal research design to investigate the…

  15. Phenotypic clines, energy balances and ecological responses to climate change.

    PubMed

    Buckley, Lauren B; Nufio, César R; Kingsolver, Joel G

    2014-01-01

    The Metabolic Theory of Ecology has renewed interest in using energetics to scale across levels of ecological organization. Can scaling from individual phenotypes to population dynamics provides insight into why species have shifted their phenologies, abundances and distributions idiosyncratically in response to recent climate change? We consider how the energetic implications of phenotypes may scale to understand population and species level responses to climate change using four focal grasshopper species along an elevation gradient in Colorado. We use a biophysical model to translate phenotypes and environmental conditions into estimates of body temperatures. We measure thermal tolerances and preferences and metabolic rates to assess rates of energy use and acquisition. Body mass declines along the elevation gradient for all species, but mass-specific metabolic rates increases only modestly. We find interspecific differences in both overall thermal tolerances and preferences and in the variation of these metrics along the elevation gradient. The more dispersive species exhibit significantly higher thermal tolerance and preference consistent with much of their range spanning hot, low elevation areas. When integrating these metrics to consider metabolic constraints, we find that energetic costs decrease along the elevation gradient due to decreasing body size and temperature. Opportunities for energy acquisition, as reflected by the proportion of time that falls within a grasshopper's thermal tolerance range, peak at mid elevations. We discuss methods for translating these energetic metrics into population dynamics. Quantifying energy balances and allocation offers a viable approach for predicting how populations will respond to climate change and the consequences for species composed of populations that may be locally adapted.

  16. Molecular road ecology: exploring the potential of genetics for investigating transportation impacts on wildlife.

    PubMed

    Balkenhol, Niko; Waits, Lisette P

    2009-10-01

    Transportation infrastructures such as roads, railroads and canals can have major environmental impacts. Ecological road effects include the destruction and fragmentation of habitat, the interruption of ecological processes and increased erosion and pollution. Growing concern about these ecological road effects has led to the emergence of a new scientific discipline called road ecology. The goal of road ecology is to provide planners with scientific advice on how to avoid, minimize or mitigate negative environmental impacts of transportation. In this review, we explore the potential of molecular genetics to contribute to road ecology. First, we summarize general findings from road ecology and review studies that investigate road effects using genetic data. These studies generally focus only on barrier effects of roads on local genetic diversity and structure and only use a fraction of available molecular approaches. Thus, we propose additional molecular applications that can be used to evaluate road effects across multiple scales and dimensions of the biodiversity hierarchy. Finally, we make recommendations for future research questions and study designs that would advance molecular road ecology. Our review demonstrates that molecular approaches can substantially contribute to road ecology research and that interdisciplinary, long-term collaborations will be particularly important for realizing the full potential of molecular road ecology.

  17. Using historic aerial photography and paleohydrologic techniques to assess long-term ecological response to two Montana dam removals.

    PubMed

    Schmitz, Denine; Blank, Matt; Ammondt, Selita; Patten, Duncan T

    2009-07-01

    The restorative potential of dam removal on ecosystem function depends on the reversibility of dam effects and its operations. While dam removal is an established engineering practice, the need for an understanding of the ecological response remains. We used paleoflood hydrology, hydrologic modeling, and aerial photo interpretation to investigate the long-term ecologic responses to dam failure and breach. We investigated downstream geomorphic and vegetation responses to a dam failure (Pattengail Dam in 1927) and a controlled dam breach, which used natural sediment removal (Mystic Lake Dam in 1985). Our data showed vegetation responses indicative of channel and floodplain evolution at Pattengail. The size of the flood following the Pattengail dam failure initiated a series of channel adjustments and reworked over 19ha of floodplain downstream of the dam. In Mystic, we observed few flood stage indicators and a slight response in floodplain vegetation. We made several findings. (1) Dam removal effects on channel evolution and floodplain development depend on reach types and their responsiveness to flow regime change. (2) Ecologic response to dam removal depends on the sizes and timing of high flow events during and following removal. (3) Paleohydrology can be used to assess historic floods (>20 years). We see the utility of assessing the ecological responsiveness of a system to previous fluvial events or changes in flow regime. Informed about the character of a system based on its history, dam removal scientists can use these tools to set realistic restoration goals for removing a dam. PMID:19042079

  18. Using historic aerial photography and paleohydrologic techniques to assess long-term ecological response to two Montana dam removals.

    PubMed

    Schmitz, Denine; Blank, Matt; Ammondt, Selita; Patten, Duncan T

    2009-07-01

    The restorative potential of dam removal on ecosystem function depends on the reversibility of dam effects and its operations. While dam removal is an established engineering practice, the need for an understanding of the ecological response remains. We used paleoflood hydrology, hydrologic modeling, and aerial photo interpretation to investigate the long-term ecologic responses to dam failure and breach. We investigated downstream geomorphic and vegetation responses to a dam failure (Pattengail Dam in 1927) and a controlled dam breach, which used natural sediment removal (Mystic Lake Dam in 1985). Our data showed vegetation responses indicative of channel and floodplain evolution at Pattengail. The size of the flood following the Pattengail dam failure initiated a series of channel adjustments and reworked over 19ha of floodplain downstream of the dam. In Mystic, we observed few flood stage indicators and a slight response in floodplain vegetation. We made several findings. (1) Dam removal effects on channel evolution and floodplain development depend on reach types and their responsiveness to flow regime change. (2) Ecologic response to dam removal depends on the sizes and timing of high flow events during and following removal. (3) Paleohydrology can be used to assess historic floods (>20 years). We see the utility of assessing the ecological responsiveness of a system to previous fluvial events or changes in flow regime. Informed about the character of a system based on its history, dam removal scientists can use these tools to set realistic restoration goals for removing a dam.

  19. A Database and Meta-Analysis of Ecological Responses to Flow in the South Atlantic Region

    SciTech Connect

    McManamay, Ryan A; Orth, Dr. Donald J; Davis, Dr, Mary; Kauffman, John

    2013-01-01

    Generalized and quantitative relationships between flow and ecology are pivotal to developing environmental flow standards based on socially acceptable ecological conditions. Informing management at regional scales requires compiling sufficient hydrologic and ecological sources of information, identifying information gaps, and creating a framework for hypothesis development and testing. We compiled studies of empirical and theoretical relationships between flow and ecology in the South Atlantic region (SAR) of the United States to evaluate their utility for the development of environmental flow standards. Using database searches, internet searches, and agency contacts, we gathered 186 sources of information that provided a qualitative or quantitative relationship between flow and ecology within states encompassing the SAR. A total of 109 of the 186 sources had sufficient information to support quantitative analyses. Ecological responses to natural changes in flow magnitude, frequency, and duration were highly variable regardless of the direction and magnitude of changes in flow. In contrast, the majority of ecological responses to anthropogenic-induced flow alterations were negative. Fish consistently showed negative responses to anthropogenic flow alterations whereas other ecological groups showed somewhat variable responses (e.g. macroinvertebrates and riparian vegetation) and even positive responses (e.g. algae). Fish and organic matter had sufficient sample sizes to stratify natural flow-ecology relationships by specific flow categories (e.g. high flow, baseflows) or by region (e.g. coastal plain, uplands). After stratifying relationships, we found that significant correlations existed between changes in natural flow and ecological responses. In addition, a regression tree explained 57% of the variation in fish responses to anthropogenic and natural changes in flow. Because of some ambiguity in interpreting the directionality in ecological responses, we

  20. ROLE OF ANTHROPOGENIC AND ENVIRONMENTAL VARIABLE ON THE PHYSIOLOGICAL AND ECOLOGICAL RESPONSES OF OYSTERS IN SOUTHWEST FLORIDA ESTUARIES

    EPA Science Inventory

    The role of freshwater alterations and seasonal changes on the ecological and physiological responses of oysters were investigated in the Caloosahatchee River, Estero Bay and Faka-Union estuaries in SW Florida. Condition index, oyster density, and disease incidence of Perkinsus m...

  1. Ecology.

    ERIC Educational Resources Information Center

    National Audubon Society, New York, NY.

    This set of teaching aids consists of nine Audubon Nature Bulletins, providing teachers and students with informational reading on various ecological topics. The bulletins have these titles: Schoolyard Laboratories, Owls and Predators, The Forest Community, Life in Freshwater Marshes, Camouflage in the Animal World, Life in the Desert, The…

  2. Risk and response in watershed ecosystems: Expanding the value of ecological risk assessments

    SciTech Connect

    Marcy, S.K.M.

    1995-12-31

    Ecological risk assessments have primarily been used to either predict, or retrospectively evaluate, the adverse effects of chemical stressors on selected ecological resources. While useful in many applications, this focus has limited value when ecological resources are simultaneously impacted by diverse chemical, physical and biological stressors, a situation typical in watersheds. With an increased emphasis on ecosystem management and watershed protection, it is critical to provide a scientific basis for evaluating and prioritizing risk and predicting the response of resources to management efforts. An expanded ecological risk assessment methodology can provide this scientific framework for improving watershed assessments by: (1) predicting both the risk and response of ecological resources to a potential range of management options, (2) including retrospective, current status, and predictive evaluations, and (3) addressing multiple diverse stressors. The effectiveness of using ecological risk assessments to improve management and decision making at the watershed level will be discussed based on the development of five watershed case studies.

  3. Responsibility-Based Youth Programs Evaluation: Investigating the Investigations.

    ERIC Educational Resources Information Center

    Hellison, Don; Walsh, David

    2002-01-01

    Reviews 26 studies that have investigated the impact of the personal-social responsibility model (RM), a physical activity program model, on underserved and/or at-risk youth since its inception. Results indicate that field research encompasses a wide range of approaches. However, the 26 studies enhance the theoretical and practical potential of RM…

  4. Ecology and Mary: An Ecological Theology of Mary as the New Eve in Response to the Church's Challenge for a Faith-Based Education in Ecological Responsibility

    ERIC Educational Resources Information Center

    Thurmond, Gloria J.

    2007-01-01

    The Church's interpretation of the current ecological crisis as a moral crisis is the catalyst for this essay, which proposes a newly constructed faith-based model for ecological dialogue and education. The exploration and reinterpretation of the traditional Church doctrine of the Virgin Mary as the new Eve provides a theme from which an…

  5. Response of Two Mytilids to a Heatwave: The Complex Interplay of Physiology, Behaviour and Ecological Interactions

    PubMed Central

    Gestoso, Ignacio; Lima, Fernando P.; Vázquez, Elsa; Comeau, Luc A.; Gomes, Filipa; Seabra, Rui

    2016-01-01

    Different combinations of behavioural and physiological responses may play a crucial role in the ecological success of species, notably in the context of biological invasions. The invasive mussel Xenostrobus securis has successfully colonised the inner part of the Galician Rias Baixas (NW Spain), where it co-occurs with the commercially-important mussel Mytilus galloprovincialis. This study investigated the effect of a heatwave on the physiological and behavioural responses in monospecific or mixed aggregations of these species. In a mesocosm experiment, mussels were exposed to simulated tidal cycles and similar temperature conditions to those experienced in the field during a heat-wave that occurred in the summer of 2013, when field robo-mussels registered temperatures up to 44.5°C at low tide. The overall responses to stress differed markedly between the two species. In monospecific aggregations M. galloprovincialis was more vulnerable than X. securis to heat exposure during emersion. However, in mixed aggregations, the presence of the invader was associated with lower mortality in M. galloprovincialis. The greater sensitivity of M. galloprovincialis to heat exposure was reflected in a higher mortality level, greater induction of Hsp70 protein and higher rates of respiration and gaping activity, which were accompanied by a lower heart rate (bradycardia). The findings show that the invader enhanced the physiological performance of M. galloprovincialis, highlighting the importance of species interactions in regulating responses to environmental stress. Understanding the complex interactions between ecological factors and physiological and behavioural responses of closely-related species is essential for predicting the impacts of invasions in the context of future climate change. PMID:27736896

  6. The Socio-ecological Fit of Human Responses to Environmental Degradation: An Integrated Assessment Methodology.

    PubMed

    Briassoulis, Helen

    2015-12-01

    The scientific and policy interest in the human responses to environmental degradation usually focuses on responses sensu stricto and 'best practices' that potentially abate degradation in affected areas. The transfer of individual, discrete instruments and 'best practices' to different contexts is challenging, however, because socio-ecological systems are complex and environmental degradation is contextual and contingent. To sensibly assess the effectiveness of formal and informal interventions to combat environmental degradation, the paper proposes an integrative, non-reductionist analytic, the 'response assemblage', for the study of 'responses-in-context,' i.e., products of human decisions to utilize environmental resources to satisfy human needs in socio-ecological systems. Response assemblages are defined as geographically and historically unique, provisional, open, territorial wholes, complex compositions emerging from processes of assembling biophysical and human components, including responses sensu stricto, from affected focal and other socio-ecological systems, to serve human goals, one of which may be combatting environmental degradation. The degree of match among the components, called the socio-ecological fit of the response assemblage, indicates how effectively their contextual and contingent interactions maintain the socio-ecological resilience, promote sustainable development, and secure the continuous provision of ecosystem services in a focal socio-ecological system. The paper presents a conceptual approach to the analysis of the socio-ecological fit of response assemblages and details an integrated assessment methodology synthesizing the resilience, assemblage, and 'problem of fit' literature. Lastly, it summarizes the novelty, value, and policy relevance of conceptualizing human responses as response assemblages and of the integrated assessment methodology, reconsiders 'best practices' and suggests selected future research directions.

  7. The Socio-ecological Fit of Human Responses to Environmental Degradation: An Integrated Assessment Methodology

    NASA Astrophysics Data System (ADS)

    Briassoulis, Helen

    2015-12-01

    The scientific and policy interest in the human responses to environmental degradation usually focuses on responses sensu stricto and `best practices' that potentially abate degradation in affected areas. The transfer of individual, discrete instruments and `best practices' to different contexts is challenging, however, because socio-ecological systems are complex and environmental degradation is contextual and contingent. To sensibly assess the effectiveness of formal and informal interventions to combat environmental degradation, the paper proposes an integrative, non-reductionist analytic, the `response assemblage', for the study of `responses-in-context,' i.e., products of human decisions to utilize environmental resources to satisfy human needs in socio-ecological systems. Response assemblages are defined as geographically and historically unique, provisional, open, territorial wholes, complex compositions emerging from processes of assembling biophysical and human components, including responses sensu stricto, from affected focal and other socio-ecological systems, to serve human goals, one of which may be combatting environmental degradation. The degree of match among the components, called the socio- ecological fit of the response assemblage, indicates how effectively their contextual and contingent interactions maintain the socio-ecological resilience, promote sustainable development, and secure the continuous provision of ecosystem services in a focal socio-ecological system. The paper presents a conceptual approach to the analysis of the socio-ecological fit of response assemblages and details an integrated assessment methodology synthesizing the resilience, assemblage, and `problem of fit' literature. Lastly, it summarizes the novelty, value, and policy relevance of conceptualizing human responses as response assemblages and of the integrated assessment methodology, reconsiders `best practices' and suggests selected future research directions.

  8. The Socio-ecological Fit of Human Responses to Environmental Degradation: An Integrated Assessment Methodology.

    PubMed

    Briassoulis, Helen

    2015-12-01

    The scientific and policy interest in the human responses to environmental degradation usually focuses on responses sensu stricto and 'best practices' that potentially abate degradation in affected areas. The transfer of individual, discrete instruments and 'best practices' to different contexts is challenging, however, because socio-ecological systems are complex and environmental degradation is contextual and contingent. To sensibly assess the effectiveness of formal and informal interventions to combat environmental degradation, the paper proposes an integrative, non-reductionist analytic, the 'response assemblage', for the study of 'responses-in-context,' i.e., products of human decisions to utilize environmental resources to satisfy human needs in socio-ecological systems. Response assemblages are defined as geographically and historically unique, provisional, open, territorial wholes, complex compositions emerging from processes of assembling biophysical and human components, including responses sensu stricto, from affected focal and other socio-ecological systems, to serve human goals, one of which may be combatting environmental degradation. The degree of match among the components, called the socio-ecological fit of the response assemblage, indicates how effectively their contextual and contingent interactions maintain the socio-ecological resilience, promote sustainable development, and secure the continuous provision of ecosystem services in a focal socio-ecological system. The paper presents a conceptual approach to the analysis of the socio-ecological fit of response assemblages and details an integrated assessment methodology synthesizing the resilience, assemblage, and 'problem of fit' literature. Lastly, it summarizes the novelty, value, and policy relevance of conceptualizing human responses as response assemblages and of the integrated assessment methodology, reconsiders 'best practices' and suggests selected future research directions. PMID

  9. Biological and ecological responses to carbon-based nanomaterials

    NASA Astrophysics Data System (ADS)

    Ratnikova, Tatsiana A.

    This dissertation examines the biological and ecological responses to carbon nanoparticles, a major class of nanomaterials which have been mass produced and extensively studied for their rich physical properties and commercial values. Chapter I of this dissertation offers a comprehensive review on the structures, properties, applications, and implications of carbon nanomaterials, especially related to the perspectives of biological and ecosystems. Given that there are many types of carbon nanomaterials available, this chapter is focused on three major types of carbon-based nanomaterials only, namely, fullerenes, single walled and multi-walled carbon nanotubes. On the whole organism level, specifically, Chapter II presents a first study on the fate of fullerenes and multiwalled carbon nanotubes in rice plants, which was facilitated by the self assembly of these nanomaterials with NOM. The aspects of fullerene uptake, translocation, biodistribution, and generational transfer in the plants were examined and quantified using bright field and electron microscopy, FT-Raman, and FTIR spectroscopy. The uptake and transport of fullerene in the plant vascular system were attributed to water transpiration, convection, capillary force, and the fullerene concentration gradient from the roots to the leaves of the plants. On the cellular level, Chapter III documents the differential uptake of hydrophilic C60(OH)20 vs. amphiphilic C70-NOM complex in Allium cepa plant cells and HT-29 colon carcinoma cells. This study was conducted using a plant cell viability assay, and complemented by bright field, fluorescence and electron microscopy imaging. In particular, C60(OH)20 and C70-NOM showed contrasting uptake in both the plant and mammalian cells, due to their significant differences in physicochemistry and the presence of an extra hydrophobic plant cell wall in the plant cells. Consequently, C60(OH)20 was found to induce toxicity in Allium cepa cells but not in HT-29 cells, while C70

  10. [Ecological security evaluation of Heilongjiang Province with pressure-state-response model].

    PubMed

    Qiu, Wei; Zhao, Qing-liang; Li, Song; Chang, Chein-chi

    2008-04-01

    The ecological security index (ESI) system including 27 indices for Heilongjiang Province was built up with the pressure-state-response (P-S-R) model. The weights of the indices were determined by analytical hierarchy process (AHP) and the ecological security status classification was evaluated by the ESI model for the years of 2000-2005. Then the development trend of ecological security from 2006 to 2010 was forecasted with the grey dynamic model. The results showed that the ecological security ranked the V grade in 2000 and the III grade in 2005, indicating the increase of ecological security. The forecasting results show that the ecological security will be the III grade for 2006, the II grade for 2007-2009, and the I grade for 2010 (ideal security). Thus it can be seen that the ecological security is ascending year by year, and the ecological environment quality is obviously improved with the implementation of eco-province construction since 2000. Through the effective facilitation of eco-province construction etc., the sustainable and healthy development of ecological security will be finally realized in Heilongjiang Province.

  11. Investigating Situational Willingness to Communicate within Second Language Classrooms from an Ecological Perspective

    ERIC Educational Resources Information Center

    Cao, Yiqian

    2011-01-01

    Previous research into willingness to communicate (WTC) in L2 has focused primarily on its trait dispositions that remain stable across contexts and its situated nature is under explored. Framed with an ecological perspective on second language learning, this multiple case study investigated the dynamic and situated nature of WTC in second…

  12. An Open-Ended Investigative Microbial Ecology Laboratory for Introductory Biology

    ERIC Educational Resources Information Center

    Jones-Held, Susan; Paoletti, Robert; Glick, David; Held, Michael E.

    2010-01-01

    In this article we describe a multi-week investigative laboratory in microbial ecology/diversity and nitrogen cycling that we have used in our introductory biology course. This module encourages active student involvement in experimental design, using the scientific literature and quantitative analysis of large data sets. Students analyze soil…

  13. Integrating Quantitative Skills in Introductory Ecology: Investigations of Wild Bird Feeding Preferences

    ERIC Educational Resources Information Center

    Small, Christine J.; Newtoff, Kiersten N.

    2013-01-01

    Undergraduate biology education is undergoing dramatic changes, emphasizing student training in the "tools and practices" of science, particularly quantitative and problem-solving skills. We redesigned a freshman ecology lab to emphasize the importance of scientific inquiry and quantitative reasoning in biology. This multi-week investigation uses…

  14. Abrupt rise of new machine ecology beyond human response time

    PubMed Central

    Johnson, Neil; Zhao, Guannan; Hunsader, Eric; Qi, Hong; Johnson, Nicholas; Meng, Jing; Tivnan, Brian

    2013-01-01

    Society's techno-social systems are becoming ever faster and more computer-orientated. However, far from simply generating faster versions of existing behaviour, we show that this speed-up can generate a new behavioural regime as humans lose the ability to intervene in real time. Analyzing millisecond-scale data for the world's largest and most powerful techno-social system, the global financial market, we uncover an abrupt transition to a new all-machine phase characterized by large numbers of subsecond extreme events. The proliferation of these subsecond events shows an intriguing correlation with the onset of the system-wide financial collapse in 2008. Our findings are consistent with an emerging ecology of competitive machines featuring ‘crowds' of predatory algorithms, and highlight the need for a new scientific theory of subsecond financial phenomena. PMID:24022120

  15. Physiological response to etho-ecological stressors in male Alpine chamois: timescale matters!

    NASA Astrophysics Data System (ADS)

    Corlatti, Luca; Palme, Rupert; Lovari, Sandro

    2014-07-01

    From a life history perspective, glucocorticoids secreted by the neuroendocrine system, integrating different sources of stress through an adaptive feedback mechanism, may have important consequences on individual fitness. Although stress responses have been the object of several investigations, few studies have explored the role of proximate mechanisms responsible for the potential trade-offs between physiological stress and life history traits integrating social and environmental stressors. In 2011 and 2012, we collected data on faecal cortisol metabolites (FCM) in a marked male population of Alpine chamois, within the Gran Paradiso National Park (Italy). Using a model selection approach we analysed the effect of potential etho-ecological stressors such as age, social status (territorial vs. non-territorial males), minimum temperature, snow depth and precipitation on FCM variation. To correctly interpret environmentally and socially induced stress responses, we conducted model selections over multiple temporal scales defined a priori: year, cold months, spring, warm months, mating season. Over the year, FCM levels showed a negative relationship with minimum temperature, but altogether, climatic stressors had negligible effects on glucocorticoid secretion, possibly owing to good adaptations of chamois to severe weather conditions. Age was negatively related to FCM during the rut, possibly due to greater experience of older males in agonistic contests. Social status was an important determinant of FCM excretion: while both the `stress of subordination' and the `stress of domination' hypotheses received some support in spring and during the mating season, respectively, previous data suggest that only the latter may have detrimental fitness consequences on male chamois.

  16. Ecological Acclimation and Hydrologic Response: Problem Complexity and Modeling Challenges

    NASA Astrophysics Data System (ADS)

    Kumar, P.; Srinivasan, V.; Le, P. V. V.; Drewry, D.

    2012-04-01

    Elevated CO2 in the atmosphere leads to a number of acclimatory responses in different vegetation types. These may be characterized as structural such as vegetation height or foliage density, ecophysiological such as reduction in stomatal conductance, and biochemical such as photosynthetic down-regulation. Furthermore, the allocation of assimilated carbon to different vegetation parts such as leaves, roots, stem and seeds is also altered such that empirical allometric relations are no longer valid. The extent and nature of these acclimatory responses vary between C3 and C4 vegetation and across species. These acclimatory responses have significant impact on hydrologic fluxes both pertaining to water and energy with the possibility of large-scale hydrologic influence. Capturing the pathways of acclimatory response to provide accurate ecohydrologic response predictions requires incorporating subtle relationships that are accentuated under elevated CO2. The talk will discuss the challenges of modeling these as well as applications to soybean, maize and bioenergy crops such as switchgrass and miscanthus.

  17. Ecological and methodological drivers of species' distribution and phenology responses to climate change.

    PubMed

    Brown, Christopher J; O'Connor, Mary I; Poloczanska, Elvira S; Schoeman, David S; Buckley, Lauren B; Burrows, Michael T; Duarte, Carlos M; Halpern, Benjamin S; Pandolfi, John M; Parmesan, Camille; Richardson, Anthony J

    2016-04-01

    Climate change is shifting species' distribution and phenology. Ecological traits, such as mobility or reproductive mode, explain variation in observed rates of shift for some taxa. However, estimates of relationships between traits and climate responses could be influenced by how responses are measured. We compiled a global data set of 651 published marine species' responses to climate change, from 47 papers on distribution shifts and 32 papers on phenology change. We assessed the relative importance of two classes of predictors of the rate of change, ecological traits of the responding taxa and methodological approaches for quantifying biological responses. Methodological differences explained 22% of the variation in range shifts, more than the 7.8% of the variation explained by ecological traits. For phenology change, methodological approaches accounted for 4% of the variation in measurements, whereas 8% of the variation was explained by ecological traits. Our ability to predict responses from traits was hindered by poor representation of species from the tropics, where temperature isotherms are moving most rapidly. Thus, the mean rate of distribution change may be underestimated by this and other global syntheses. Our analyses indicate that methodological approaches should be explicitly considered when designing, analysing and comparing results among studies. To improve climate impact studies, we recommend that (1) reanalyses of existing time series state how the existing data sets may limit the inferences about possible climate responses; (2) qualitative comparisons of species' responses across different studies be limited to studies with similar methodological approaches; (3) meta-analyses of climate responses include methodological attributes as covariates; and (4) that new time series be designed to include the detection of early warnings of change or ecologically relevant change. Greater consideration of methodological attributes will improve the accuracy

  18. Ecological and methodological drivers of species' distribution and phenology responses to climate change.

    PubMed

    Brown, Christopher J; O'Connor, Mary I; Poloczanska, Elvira S; Schoeman, David S; Buckley, Lauren B; Burrows, Michael T; Duarte, Carlos M; Halpern, Benjamin S; Pandolfi, John M; Parmesan, Camille; Richardson, Anthony J

    2016-04-01

    Climate change is shifting species' distribution and phenology. Ecological traits, such as mobility or reproductive mode, explain variation in observed rates of shift for some taxa. However, estimates of relationships between traits and climate responses could be influenced by how responses are measured. We compiled a global data set of 651 published marine species' responses to climate change, from 47 papers on distribution shifts and 32 papers on phenology change. We assessed the relative importance of two classes of predictors of the rate of change, ecological traits of the responding taxa and methodological approaches for quantifying biological responses. Methodological differences explained 22% of the variation in range shifts, more than the 7.8% of the variation explained by ecological traits. For phenology change, methodological approaches accounted for 4% of the variation in measurements, whereas 8% of the variation was explained by ecological traits. Our ability to predict responses from traits was hindered by poor representation of species from the tropics, where temperature isotherms are moving most rapidly. Thus, the mean rate of distribution change may be underestimated by this and other global syntheses. Our analyses indicate that methodological approaches should be explicitly considered when designing, analysing and comparing results among studies. To improve climate impact studies, we recommend that (1) reanalyses of existing time series state how the existing data sets may limit the inferences about possible climate responses; (2) qualitative comparisons of species' responses across different studies be limited to studies with similar methodological approaches; (3) meta-analyses of climate responses include methodological attributes as covariates; and (4) that new time series be designed to include the detection of early warnings of change or ecologically relevant change. Greater consideration of methodological attributes will improve the accuracy

  19. Ecological Impacts During the Deepwater Horizon Oil Spill Response

    EPA Science Inventory

    The Deepwater Horizon (DWH) oil spill was the largest environmental disaster and response effort in U.S. history, with nearly 800 million liters of crude oil spilled. Vast areas of the Gulf of Mexico were contaminated with oil, including deep-ocean communities and over 1,600 kilo...

  20. Feasibility and validity of ecological momentary assessment in the investigation of suicide risk.

    PubMed

    Husky, Mathilde; Olié, Emilie; Guillaume, Sébastien; Genty, Catherine; Swendsen, Joel; Courtet, Philippe

    2014-12-15

    Ecological Momentary Assessment has been used to investigate a wide range of behaviors and psychiatric conditions. Previous investigations have consistently obtained promising results with high acceptance and compliance rates, and with only minor reactive effects for specific variables. Despite the promise of this methodology for the study of severe psychiatric populations, little is known about its feasibility in samples at risk for suicide. In the present study, four samples at varying risk for suicide completed an Ecological Momentary Assessment study by responding to five electronic assessments per day over a one-week period. Samples included healthy controls (n=13), affective controls (n=21), past suicide attempters (n=20), and recent suicide attempters (n=42). The results demonstrate satisfactory participation rates and high compliance with daily life repeated assessments across all groups. Importantly, negative thoughts or suicidal ideation were not reactive to the duration of the study, indicating that the repeated assessment of such cognitions in daily life have little or no effect on their frequency. The findings provide support for the use of Ecological Momentary Assessment in the study of suicidal ideation and suggest that mobile technologies represent new opportunities for the assessment of high-risk cognitive states experienced by patients in daily life.

  1. Investigating the environmental Kuznets curve hypothesis: the role of tourism and ecological footprint.

    PubMed

    Ozturk, Ilhan; Al-Mulali, Usama; Saboori, Behnaz

    2016-01-01

    The main objective of this study is to examine the environmental Kuznets curve (EKC) hypothesis by utilizing the ecological footprint as an environment indicator and GDP from tourism as the economic indicator. To achieve this goal, an environmental degradation model is established during the period of 1988-2008 for 144 countries. The results from the time series generalized method of moments (GMM) and the system panel GMM revealed that the number of countries that have a negative relationship between the ecological footprint and its determinants (GDP growth from tourism, energy consumption, trade openness, and urbanization) is more existent in the upper middle- and high-income countries. Moreover, the EKC hypothesis is more present in the upper middle- and high-income countries than the other income countries. From the outcome of this research, a number of policy recommendations were provided for the investigated countries. PMID:26408117

  2. Investigating the environmental Kuznets curve hypothesis: the role of tourism and ecological footprint.

    PubMed

    Ozturk, Ilhan; Al-Mulali, Usama; Saboori, Behnaz

    2016-01-01

    The main objective of this study is to examine the environmental Kuznets curve (EKC) hypothesis by utilizing the ecological footprint as an environment indicator and GDP from tourism as the economic indicator. To achieve this goal, an environmental degradation model is established during the period of 1988-2008 for 144 countries. The results from the time series generalized method of moments (GMM) and the system panel GMM revealed that the number of countries that have a negative relationship between the ecological footprint and its determinants (GDP growth from tourism, energy consumption, trade openness, and urbanization) is more existent in the upper middle- and high-income countries. Moreover, the EKC hypothesis is more present in the upper middle- and high-income countries than the other income countries. From the outcome of this research, a number of policy recommendations were provided for the investigated countries.

  3. Ecological Genetics of Vernalization Response in Bromus tectorum L. (Poaceae)

    PubMed Central

    MEYER, SUSAN E.; NELSON, DAVID L.; CARLSON, STEPHANIE L.

    2004-01-01

    • Background and Aims Bromus tectorum (cheatgrass or downy brome) is an exotic annual grass that is dominant over large areas of former shrubland in western North America. To flower in time for seed production in early summer, B. tectorum plants generally require vernalization at winter temperatures, either as imbibed seeds or as established seedlings. • Methods Variation in response to increasing periods of vernalization as seeds or seedlings for progeny of ten full‐sib families from each of four B. tectorum populations from contrasting habitats was studied. • Key Results As vernalization was increased from 0 to 10 weeks, the proportion of plants flowering within 20 weeks increased, weeks to initiation of flowering decreased, and seed yield per plant increased, regardless of whether plants were vernalized as seeds or seedlings. Most of the variation was accounted for by differences among populations. Plants of the warm desert population flowered promptly even without vernalization, while those of the cold desert, foothill and montane populations showed incremental changes in response variables as a function of vernalization period. Populations differed in among‐family variance, with the warm desert population generally showing the least variance and the cold desert population the most. Variation among populations and among families within populations decreased as vernalization period increased, whereas the non‐genetic component of variance showed no such pattern. • Conclusions Variation in vernalization response was found to be adaptively significant and apparently represents the result of contrasting selection regimes on a range of founder genotypes. PMID:15087300

  4. Ecological response to hydrological variability and catchment development: Insights from a shallow oxbow lake in Lower Mississippi Valley, Arkansas.

    PubMed

    Bhattacharya, Ruchi; Hausmann, Sonja; Hubeny, J Bradford; Gell, Peter; Black, Jessica L

    2016-11-01

    The ecological response of shallow oxbow lakes to variability in hydrology and catchment development in large river floodplain ecosystems (RFE) in Arkansas remains largely unknown. Investigating these responses will advance our understanding of ecological evolution of oxbow lakes in response to the major environmental drivers, which will establish baseline conditions required to develop effective management practices for RFE. In this pilot study, we examined the potential of using a dated surface sediment core from Adams Bayou, a floodplain lake located within the Cache-Lower White River Ramsar site in SE Arkansas. Stratigraphic records of diatoms and sediment geochemistry were used to ascertain variation in Adams Bayou's ecological condition. During 1968-2008, in response to hydrological and anthropogenic changes, Adams Bayou's diatom assemblages progressed from predominantly benthic (Gomphonema parvulum and Meridion circulare) to primarily planktonic assemblage (Aulacoseira granulata and Cyclotella meneghiniana), along with a decrease in magnetic susceptibility (k) and % silt. Statistical analyses reveled that during 1968-2000, higher hydrological connectivity and catchment alterations drove Adams Bayou's ecosystem. After 2000, lower hydrological connectivity and increase in cultivation were the major drivers. The potential impact of increasing air temperature was also noted. The shift in Adams Bayou from a connected, clear, mesotrophic state to a relatively isolated, turbid and nutrient enriched state is consistent with regime shift models and highlights its sensitivity to a combination of environmental stresses prevalent in the catchment. Although fluvial systems pose challenges in establishing clear chronologies, oxbow lake sediments can be a effective paleoecological archives. Our work provides clear evidence for the change in the ecological character of this wetland of international significance and flags the need for a wider assessment of water bodies

  5. Ecological response to hydrological variability and catchment development: Insights from a shallow oxbow lake in Lower Mississippi Valley, Arkansas.

    PubMed

    Bhattacharya, Ruchi; Hausmann, Sonja; Hubeny, J Bradford; Gell, Peter; Black, Jessica L

    2016-11-01

    The ecological response of shallow oxbow lakes to variability in hydrology and catchment development in large river floodplain ecosystems (RFE) in Arkansas remains largely unknown. Investigating these responses will advance our understanding of ecological evolution of oxbow lakes in response to the major environmental drivers, which will establish baseline conditions required to develop effective management practices for RFE. In this pilot study, we examined the potential of using a dated surface sediment core from Adams Bayou, a floodplain lake located within the Cache-Lower White River Ramsar site in SE Arkansas. Stratigraphic records of diatoms and sediment geochemistry were used to ascertain variation in Adams Bayou's ecological condition. During 1968-2008, in response to hydrological and anthropogenic changes, Adams Bayou's diatom assemblages progressed from predominantly benthic (Gomphonema parvulum and Meridion circulare) to primarily planktonic assemblage (Aulacoseira granulata and Cyclotella meneghiniana), along with a decrease in magnetic susceptibility (k) and % silt. Statistical analyses reveled that during 1968-2000, higher hydrological connectivity and catchment alterations drove Adams Bayou's ecosystem. After 2000, lower hydrological connectivity and increase in cultivation were the major drivers. The potential impact of increasing air temperature was also noted. The shift in Adams Bayou from a connected, clear, mesotrophic state to a relatively isolated, turbid and nutrient enriched state is consistent with regime shift models and highlights its sensitivity to a combination of environmental stresses prevalent in the catchment. Although fluvial systems pose challenges in establishing clear chronologies, oxbow lake sediments can be a effective paleoecological archives. Our work provides clear evidence for the change in the ecological character of this wetland of international significance and flags the need for a wider assessment of water bodies

  6. ECOLOGICAL RESPONSES TO POLLUTION ABATEMENT: A FRAMEWORK FOR MEASUREMENT AND ASSESSMENT FOR COASTAL ECOSYSTEMS

    EPA Science Inventory

    Ecological Responses to Pollution Abatement: A Framework for Measurement and Assessment for Coastal Ecosystems (Abstract). To be presented at the 16th Biennial Conference of the Estuarine Research Foundation, ERF 2001: An Estuarine Odyssey, 4-8 November 2001, St. Pete Beach, FL. ...

  7. Measuring Early Childhood Teacher Candidates' Conceptualizations of a Culturally Responsive Classroom Ecology

    ERIC Educational Resources Information Center

    Flores, Belinda Bustos; Riojas-Cortez, Mari

    2009-01-01

    With the increase of Latino preschoolers, it is pressing that early childhood teachers are prepared to create a high quality environment in which all children can succeed. Using the frameworks of cultural responsiveness and classroom management, we developed the Early Childhood Ecology Scale (ECES) as an observational and reflective tool to…

  8. Electrophysiology Meets Ecology: Investigating How Vision is Tuned to the Life Style of an Animal using Electroretinography

    PubMed Central

    Stowasser, Annette; Mohr, Sarah; Buschbeck, Elke; Vilinsky, Ilya

    2015-01-01

    Students learn best when projects are multidisciplinary, hands-on, and provide ample opportunity for self-driven investigation. We present a teaching unit that leads students to explore relationships between sensory function and ecology. Field studies, which are rare in neurobiology education, are combined with laboratory experiments that assess visual properties of insect eyes, using electroretinography (ERG). Comprised of nearly one million species, insects are a diverse group of animals, living in nearly all habitats and ecological niches. Each of these lifestyles puts different demands on their visual systems, and accordingly, insects display a wide array of eye organizations and specializations. Physiologically relevant differences can be measured using relatively simple extracellular electrophysiological methods that can be carried out with standard equipment, much of which is already in place in most physiology laboratories. The teaching unit takes advantage of the large pool of locally available species, some of which likely show specialized visual properties that can be measured by students. In the course of the experiments, students collect local insects or other arthropods of their choice, are guided to formulate hypotheses about how the visual system of “their” insects might be tuned to the lifestyle of the species, and use ERGs to investigate the insects’ visual response dynamics, and both chromatic and temporal properties of the visual system. Students are then guided to interpret their results in both a comparative physiological and ecological context. This set of experiments closely mirrors authentic research and has proven to be a popular, informative and highly engaging teaching tool. PMID:26240534

  9. Individual responses in spring arrival date to ecological conditions during winter and migration in a migratory bird.

    PubMed

    Balbontín, Javier; Møller, Anders Pape; Hermosell, Ignacio G; Marzal, Alfonso; Reviriego, Maribel; de Lope, Florentino

    2009-09-01

    1. We studied lifetime arrival patterns in the barn swallow (Hirundo rustica L.) in relation to variation in ecological conditions, as reflected by the normalized difference vegetation index (NDVI) in the Sub-Saharan winter quarters and at stopover sites in North Africa. 2. Migratory birds have recently advanced their arrival dates, but the relative role of microevolution and phenotypic plasticity as mechanisms of response to changing environmental conditions remains unknown. To distinguish between these two possibilities, we investigated the change in the arrival date using cross-sectional and longitudinal analyses. 3. We predicted that the effect (i.e. slopes) of environmental conditions in stopover or winter areas on arrival date should be similar using cross-sectional and longitudinal analyses in case phenotypic plasticity is the underlying mechanism, or they should differ in case microevolution is the mechanism. 4. As expected according to a previous cross-sectional study, we found an advance in the arrival date when ecological conditions improve in stopover areas and a delay in the arrival date when ecological conditions improve in the winter quarters. 5. Change in the arrival time at the breeding grounds due to ecological conditions found en route and, in the winter areas, was mainly due to phenotypic plasticity as shown by similarities in the slopes found in these relationships using cross-sectional and longitudinal analyses. 6. We also investigated sex and age of barns swallows as sources of variation in the arrival time with respect to conditions experienced in winter and stopover areas. We found that earlier arrival at the breeding grounds due to prevailing ecological conditions found en route in North Africa was similar for males and females of all age-classes. In contrast, individuals tended to delay departure when ecological conditions improved in the winter quarters, but this delay differed among age classes, with old individuals delaying departure

  10. A summary of ecological investigations at the burial ground complex, Savannah River Site - 1994

    SciTech Connect

    Friday, G.P.; Hartman, G.D.; Mackey, H.E. Jr.; Riley, R.S.; Roach, J.L.; Specht, W.L.; Westbury, H.M.; Wike, L.D.

    1994-11-01

    This report summarizes the results of three ecological investigations that were conducted in 1994 at the Burial Ground Complex (BGC) at the Savannah River Site (SRS). The three topics of study included remote sensing, aquatic toxicity testing, and qualitative surveys of herpetofauna and small mammals. Interim reports from each investigation are included in the appendices (A, B, and C). The objectives of the remote sensing effort were to compile historical aerial photography of the BGC and to develop a land use/cover map of the complex using recent aerial imagery. The goal of the aquatic toxicity testing was to determine if surface waters were toxic to aquatic biota whereas the objectives of the vertebrate surveys were to identify the species diversity and relative abundances of amphibians, reptiles, and small mammals inhabiting the study area.

  11. Gene network architecture as a canvas for the interpretation of ecological genomics investigations.

    PubMed

    Landry, Christian R; Aubin-Horth, Nadia

    2010-12-01

    New technologies promise to revolutionize the field of molecular ecology. This technological progress comes with its own set of challenges. Among the most important ones is the analysis and interpretation of the data in a way that tells us about the molecular causes of the phenotype of interest and its consequences. In this issue, Whitehead et al. (2010) reveal part of the mechanistic basis of evolved pollution tolerance by studying the developmental and transcriptional response of tolerant and sensitive fish embryos to polychlorinated biphenyls (PCBs), a pollutant commonly found in coastal waters of the United States. By integrating their gene expression profiling data with phenotypic data on individuals along with what is known about pathways by which this pollutant acts in zebrafish and mammals, they are able to suggest detailed mechanisms that have evolved to allow a fish population to adapt to a very damaging pollutant and develop normally. PMID:21091660

  12. Stem responses to damage: the evolutionary ecology of Quercus species in contrasting fire regimes.

    PubMed

    Romero, Claudia; Bolker, Benjamin M; Edwards, Christine E

    2009-01-01

    * The ability of tree stems to recover from damage is critical for tree survival and may explain species distributions across disturbance regimes. Two primary responses to stem damage, decay compartmentalization and wound closure, act in concert to limit decay and pathogen spread. A previous study demonstrated a tradeoff between wound responses that varied with anatomical traits, but its wide taxonomic range made it hard to analyze responses in an evolutionary context. * Here, we tested the stem wound responses of 13 species of Quercus inhabiting three habitats across a gradient of fire intensity. We also quantified anatomical and structural traits and phylogenetic position, in order to assess the relative contributions of ecological adaptation and phylogenetic history in determining traits. * Xylem anatomical traits were phylogenetically constrained, while phloem traits and damage responses varied with habitat. Across habitats, hammock and sandhill species closed bark wounds effectively, whereas scrub species limited the spread of xylem decay. There was a tradeoff between wound closure and decay compartmentalization within the white+live oaks. * The fact that some wound response traits are phylogenetically constrained while others respond to ecological pressures suggests that damage responses integrate mechanisms operating at several levels within plants. PMID:19140949

  13. Comparative Functional Responses Predict the Invasiveness and Ecological Impacts of Alien Herbivorous Snails.

    PubMed

    Xu, Meng; Mu, Xidong; Dick, Jaimie T A; Fang, Miao; Gu, Dangen; Luo, Du; Zhang, Jiaen; Luo, Jianren; Hu, Yinchang

    2016-01-01

    Understanding determinants of the invasiveness and ecological impacts of alien species is amongst the most sought-after and urgent research questions in ecology. Several studies have shown the value of comparing the functional responses (FRs) of alien and native predators towards native prey, however, the technique is under-explored with herbivorous alien species and as a predictor of invasiveness as distinct from ecological impact. Here, in China, we conducted a mesocosm experiment to compare the FRs among three herbivorous snail species: the golden apple snail, Pomacea canaliculata, a highly invasive and high impact alien listed in "100 of the World's Worst Invasive Alien Species"; Planorbarius corneus, a non-invasive, low impact alien; and the Chinese native snail, Bellamya aeruginosa, when feeding on four locally occurring plant species. Further, by using a numerical response equation, we modelled the population dynamics of the snail consumers. For standard FR parameters, we found that the invasive and damaging alien snail had the highest "attack rates" a, shortest "handling times" h and also the highest estimated maximum feeding rates, 1/hT, whereas the native species had the lowest attack rates, longest handling times and lowest maximum feeding rates. The non-invasive, low impact alien species had consistently intermediate FR parameters. The invasive alien species had higher population growth potential than the native snail species, whilst that of the non-invasive alien species was intermediate. Thus, while the comparative FR approach has been proposed as a reliable method for predicting the ecological impacts of invasive predators, our results further suggest that comparative FRs could extend to predict the invasiveness and ecological impacts of alien herbivores and should be explored in other taxa and trophic groups to determine the general utility of the approach.

  14. Comparative Functional Responses Predict the Invasiveness and Ecological Impacts of Alien Herbivorous Snails

    PubMed Central

    Xu, Meng; Mu, Xidong; Dick, Jaimie T. A.; Fang, Miao; Gu, Dangen; Luo, Du; Zhang, Jiaen; Luo, Jianren; Hu, Yinchang

    2016-01-01

    Understanding determinants of the invasiveness and ecological impacts of alien species is amongst the most sought-after and urgent research questions in ecology. Several studies have shown the value of comparing the functional responses (FRs) of alien and native predators towards native prey, however, the technique is under-explored with herbivorous alien species and as a predictor of invasiveness as distinct from ecological impact. Here, in China, we conducted a mesocosm experiment to compare the FRs among three herbivorous snail species: the golden apple snail, Pomacea canaliculata, a highly invasive and high impact alien listed in “100 of the World's Worst Invasive Alien Species”; Planorbarius corneus, a non-invasive, low impact alien; and the Chinese native snail, Bellamya aeruginosa, when feeding on four locally occurring plant species. Further, by using a numerical response equation, we modelled the population dynamics of the snail consumers. For standard FR parameters, we found that the invasive and damaging alien snail had the highest “attack rates” a, shortest “handling times” h and also the highest estimated maximum feeding rates, 1/hT, whereas the native species had the lowest attack rates, longest handling times and lowest maximum feeding rates. The non-invasive, low impact alien species had consistently intermediate FR parameters. The invasive alien species had higher population growth potential than the native snail species, whilst that of the non-invasive alien species was intermediate. Thus, while the comparative FR approach has been proposed as a reliable method for predicting the ecological impacts of invasive predators, our results further suggest that comparative FRs could extend to predict the invasiveness and ecological impacts of alien herbivores and should be explored in other taxa and trophic groups to determine the general utility of the approach. PMID:26771658

  15. Investigation of paramagnetic response of metallic epoxies

    NASA Technical Reports Server (NTRS)

    Ash, R. L.; Chegini, H.

    1986-01-01

    The paramagnetic properties of epoxies which were impregnated with metal ions were examined as the primary task in this research. A major conclusion was that the quality control of the epoxies was insufficient to permit reliable evaluation. Subsequently, a new set of specimens is being prepared. As an additional task, a new method is investigated for estimating heats of combustion for saturated hydrocarbons. The results of that investigation have shown that the empirical approach is a promising method for on-line measurements.

  16. Community responses to contaminants: using basic ecological principles to predict ecotoxicological effects.

    PubMed

    Clements, William H; Rohr, Jason R

    2009-09-01

    Community ecotoxicology is defined as the study of the effects of contaminants on patterns of species abundance, diversity, community composition, and species interactions. Recent discoveries that species diversity is positively associated with ecosystem stability, recovery, and services have made a community-level perspective on ecotoxicology more important than ever. Community ecotoxicology must explicitly consider both present and impending global change and shift from a purely descriptive to a more predictive science. Greater consideration of the ecological factors and threshold responses that determine community resistance and resilience should improve our ability to predict how and when communities will respond to, and recover from, xenobiotics. A better understanding of pollution-induced community tolerance, and of the costs of this tolerance, should facilitate identifying contaminant-impacted communities, thus forecasting the ecological consequences of contaminant exposure and determining the restoration effectiveness. Given the vast complexity of community ecotoxicology, simplifying assumptions, such as the possibility that the approximately 100,000 registered chemicals could be reduced to a more manageable number of contaminant classes with similar modes of action, must be identified and validated. In addition to providing a framework for predicting contaminant fate and effects, food-web ecology can help to identify communities that are sensitive to contaminants, contaminants that are particularly insidious to communities, and species that are crucial for transmitting adverse effects across trophic levels. Integration of basic ecological principles into the design and implementation of ecotoxicological research is essential for predicting contaminant effects within the context of rapidly changing, global environmental conditions.

  17. Ecological responses to trout habitat rehabilitation in a northern Michigan stream.

    PubMed

    Rosi-Marshall, Emma J; Moerke, Ashley H; Lamberti, Gary A

    2006-07-01

    Monitoring of stream restoration projects is often limited and success often focuses on a single taxon (e.g., salmonids), even though other aspects of stream structure and function may also respond to restoration activities. The Ottawa National Forest (ONF), Michigan, conducted a site-specific trout habitat improvement to enhance the trout fishery in Cook's Run, a 3rd-order stream that the ONF determined was negatively affected by past logging. Our objectives were to determine if the habitat improvement increased trout abundances and enhanced other ecological variables (overall habitat quality, organic matter retention, seston concentration, periphyton abundance, sediment organic matter content, and macroinvertebrate abundance and diversity) following rehabilitation. The addition of skybooms (underbank cover structures) and k-dams (pool-creating structures) increased the relative abundance of harvestable trout (>25 cm in total length) as intended but not overall trout abundances. Both rehabilitation techniques also increased maximum channel depth and organic matter retention, but only k-dams increased overall habitat quality. Neither approach significantly affected other ecological variables. The modest ecological response to this habitat improvement likely occurred because the system was not severely degraded beforehand, and thus small, local changes in habitat did not measurably affect most physical and ecological variables measured. However, increases in habitat volume and in organic matter retention may enhance stream biota in the long term.

  18. Ecological Responses to Trout Habitat Rehabilitation in a Northern Michigan Stream

    NASA Astrophysics Data System (ADS)

    Rosi-Marshall, Emma J.; Moerke, Ashley H.; Lamberti, Gary A.

    2006-07-01

    Monitoring of stream restoration projects is often limited and success often focuses on a single taxon (e.g., salmonids), even though other aspects of stream structure and function may also respond to restoration activities. The Ottawa National Forest (ONF), Michigan, conducted a site-specific trout habitat improvement to enhance the trout fishery in Cook’s Run, a 3rd-order stream that the ONF determined was negatively affected by past logging. Our objectives were to determine if the habitat improvement increased trout abundances and enhanced other ecological variables (overall habitat quality, organic matter retention, seston concentration, periphyton abundance, sediment organic matter content, and macroinvertebrate abundance and diversity) following rehabilitation. The addition of skybooms (underbank cover structures) and k-dams (pool-creating structures) increased the relative abundance of harvestable trout (>25 cm in total length) as intended but not overall trout abundances. Both rehabilitation techniques also increased maximum channel depth and organic matter retention, but only k-dams increased overall habitat quality. Neither approach significantly affected other ecological variables. The modest ecological response to this habitat improvement likely occurred because the system was not severely degraded beforehand, and thus small, local changes in habitat did not measurably affect most physical and ecological variables measured. However, increases in habitat volume and in organic matter retention may enhance stream biota in the long term.

  19. Landscape ecological security response to land use change in the tidal flat reclamation zone, China.

    PubMed

    Zhang, Runsen; Pu, Lijie; Li, Jianguo; Zhang, Jing; Xu, Yan

    2016-01-01

    As coastal development becomes a national strategy in Eastern China, land use and landscape patterns have been affected by reclamation projects. In this study, taking Rudong County, China as a typical area, we analyzed land use change and its landscape ecological security responses in the tidal flat reclamation zone. The results show that land use change in the tidal flat reclamation zone is characterized by the replacement of natural tidal flat with agricultural and construction land, which has also led to a big change in landscape patterns. We built a landscape ecological security evaluation system, which consists of landscape interference degree and landscape fragile degree, and then calculated the landscape ecological security change in the tidal flat reclamation zone from 1990 to 2008 to depict the life cycle in tidal flat reclamation. Landscape ecological security exhibited a W-shaped periodicity, including the juvenile stage, growth stage, and maturation stage. Life-cycle analysis demonstrates that 37 years is required for the land use system to transform from a natural ecosystem to an artificial ecosystem in the tidal flat reclamation zone. PMID:26627206

  20. Landscape ecological security response to land use change in the tidal flat reclamation zone, China.

    PubMed

    Zhang, Runsen; Pu, Lijie; Li, Jianguo; Zhang, Jing; Xu, Yan

    2016-01-01

    As coastal development becomes a national strategy in Eastern China, land use and landscape patterns have been affected by reclamation projects. In this study, taking Rudong County, China as a typical area, we analyzed land use change and its landscape ecological security responses in the tidal flat reclamation zone. The results show that land use change in the tidal flat reclamation zone is characterized by the replacement of natural tidal flat with agricultural and construction land, which has also led to a big change in landscape patterns. We built a landscape ecological security evaluation system, which consists of landscape interference degree and landscape fragile degree, and then calculated the landscape ecological security change in the tidal flat reclamation zone from 1990 to 2008 to depict the life cycle in tidal flat reclamation. Landscape ecological security exhibited a W-shaped periodicity, including the juvenile stage, growth stage, and maturation stage. Life-cycle analysis demonstrates that 37 years is required for the land use system to transform from a natural ecosystem to an artificial ecosystem in the tidal flat reclamation zone.

  1. A socio-ecological investigation of options to manage groundwater degradation in the Western Desert, Egypt.

    PubMed

    King, Caroline; Salem, Boshra

    2012-07-01

    Under increasing water scarcity, collective groundwater management is a global concern. This article presents an interdisciplinary analysis of this challenge drawing on a survey including 50 large and small farms and gardens in a village in an agricultural land reclamation area on the edge of the Western Desert of Egypt. Findings revealed that smallholders rely on a practice of shallow groundwater use, through which drainage water from adjacent irrigation areas is effectively recycled within the surface aquifer. Expanding agroindustrial activities in the surrounding area are socio-economically important, but by mining non-renewable water in the surrounding area, they set in motion a degradation process with social and ecological consequences for all users in the multi-layered aquifer system. Based on the findings of our investigation, we identify opportunities for local authorities to more systematically connect available environmental information sources and common pool resource management precedents, to counterbalance the degradation threat.

  2. Ecological investigation of three geophytes in the Deltaic Mediterranean coast of Egypt.

    PubMed

    Maswada, Hanafey F; Elzaawely, Abdelnaser A

    2013-12-01

    This study was conducted to investigate the ecological features of three geophytes namely Asparagus stipularis, Cyperus capitatus and Stipagrostis lanata which grow naturally in the Nile Delta coast of Egypt. C. capitatus and S. lanata are growing in non-saline sandy soils and can tolerate drought stress while, A. stipularis is growing in saline and non-saline sandy and calcareous clay soils and can tolerate drought and salt stress. Multivariate analysis of the vegetation of 100 sampled stands supporting growth of the three geophytic species in the study area led to the recognition of four vegetation groups namely, (A) Alhagi graecorum, (B) Cyperus capitatus, (C) Lycium schweinfurthii var. schweinfurthii-Asparagus stipularis and (D) Juncus acutus subsp. acutus. Vegetationally, the vegetation groups associated with the three species can be distinguished into two community types. The first one is psammophytic community comprising vegetation groups A and B that may represent the non-saline sand formations (flats, hummocks and dunes). The second one is halophytic community including vegetation groups C and D that may represent the saline sand flats and salt marsh habitat types, respectively. Sodium adsorption ratio, electrical conductivity, sodium cation, chlorides, silt and sand fractions, pH value, moisture content, bicarbonates and available phosphorus were the most effective soil factors that controlling the abundance and distribution of the plant communities associated with the investigated geophytes. This study showed the ecological features of the selected geophytes in terms of their habitats, associated plant communities and the most edaphic factors controlling their richness and distribution in the study area.

  3. Ecological investigation of three geophytes in the Deltaic Mediterranean coast of Egypt.

    PubMed

    Maswada, Hanafey F; Elzaawely, Abdelnaser A

    2013-12-01

    This study was conducted to investigate the ecological features of three geophytes namely Asparagus stipularis, Cyperus capitatus and Stipagrostis lanata which grow naturally in the Nile Delta coast of Egypt. C. capitatus and S. lanata are growing in non-saline sandy soils and can tolerate drought stress while, A. stipularis is growing in saline and non-saline sandy and calcareous clay soils and can tolerate drought and salt stress. Multivariate analysis of the vegetation of 100 sampled stands supporting growth of the three geophytic species in the study area led to the recognition of four vegetation groups namely, (A) Alhagi graecorum, (B) Cyperus capitatus, (C) Lycium schweinfurthii var. schweinfurthii-Asparagus stipularis and (D) Juncus acutus subsp. acutus. Vegetationally, the vegetation groups associated with the three species can be distinguished into two community types. The first one is psammophytic community comprising vegetation groups A and B that may represent the non-saline sand formations (flats, hummocks and dunes). The second one is halophytic community including vegetation groups C and D that may represent the saline sand flats and salt marsh habitat types, respectively. Sodium adsorption ratio, electrical conductivity, sodium cation, chlorides, silt and sand fractions, pH value, moisture content, bicarbonates and available phosphorus were the most effective soil factors that controlling the abundance and distribution of the plant communities associated with the investigated geophytes. This study showed the ecological features of the selected geophytes in terms of their habitats, associated plant communities and the most edaphic factors controlling their richness and distribution in the study area. PMID:24506033

  4. Ecology and vegetarian considerations: does environmental responsibility demand the elimination of livestock?

    PubMed

    Gussow, J D

    1994-05-01

    Although the recommendation to avoid animal flesh for environmental reasons has been increasingly advanced, especially in the highly industrialized countries, the ecological implications of such avoidance are seldom carefully examined. If sustainable food systems are to be modeled after natural systems that maintain fertility, both plants and animals would be involved. This paper examines the history of the idea that environmental responsibility is linked to vegetarianism and the destructive effects of present methods of animal raising on farmers, animal welfare, and the environment. Finally, it explores the question of whether vegetarianism is the appropriate response to these problems.

  5. A causal model of the linkages between innovative ecological responsiveness and performance

    NASA Astrophysics Data System (ADS)

    Williams, Johnnie

    The purpose of this study was to examine the question "What are the organizational "antecedents" and "downstream" effects of innovative ecological responsiveness in the electric service industry?" Data were collected primarily from the chief operating, financial, and environmental/regulatory officers from 101 investor owned electric power producers across the United States. Theory from the organizational innovation literature was integrated with the organizational adaptation literature to identify the relationship between the organizational determinants of innovative adaptive responses, as well as to project the financial implications of these responses. Since innovations are a means of introducing change into organizations in order to facilitate the adaptation process, these two theoretical frameworks were found to be quite complementary. Statistical results suggest that "culture and context" matter. Managerial ideology was found to be significantly related to innovative ecological responsiveness. Regulatory uncertainty was significantly and positively related to the range of innovative responses implemented by a company. The range of innovative activities implemented by a company had a significant positive effect on financial performance. This finding suggests that firms that adopt a broad range of activities tend to perform better, indicating a possible synergistic effect in this adaptive pattern.

  6. Development of stressor-response models for an ecological risk assessment case study

    SciTech Connect

    Nacci, D.E.; Munns, W.R.; Cayula, S.; Serbst, J.; Johnston, R.K.; Walker, H.A.

    1994-12-31

    An estuarine ecological risk assessment for the Portsmouth Naval Shipyard (Kittery, ME) is being conducted following the US EPA`s Framework for Ecological Risk Assessment (ERA). As part of the Analysis phase of the ERA, laboratory studies were conducted to develop stressor-response models for lead, the primary contaminant of concern. Thirty-day exposures to adult sea urchins, Arbacia punctulata, occurred via food or suspended sediment. Exposure media were amended with lead sulfate to 10--100 or 100--300 times uncontaminated levels for the Feeding or Sediment Experiments, respectively. The sea urchin experimental model was selected because it permitted the measurement of biological endpoints with significance at the population level (e.g., adult survival and reproduction success), including those used in standard marine bioassays (i.e., fertilization and larval development). Feeding Experiment treatments produced few effects. Sediment Experiment treatments resulted in reductions in survival, growth and reproductive output of exposed adults and were directly toxic to early lifestages. However, in uncontaminated sea water, gametes from Sediment Experiment adults fertilized and completed larval development normally. Data from these experimental systems will be used to produce models relating lead exposure to specific biological responses and, ultimately, ecological risk.

  7. "My worries are rational, climate change is not": habitual ecological worrying is an adaptive response.

    PubMed

    Verplanken, Bas; Roy, Deborah

    2013-01-01

    Qualifications such as "global warming hysteria" and "energy policy schizophrenia" put forward by some climate change skeptics, usually outside the academic arena, may suggest that people who seriously worry about the environment suffer from psychological imbalance. The present study aimed to refute this thesis. While habitual worrying in general is strongly associated with psychopathological symptoms, in a survey a near-zero correlation was found between habitual ecological worrying and pathological worry. Instead, habitual ecological worrying was associated with pro-environmental attitudes and behaviors, and with a personality structure characterized by imagination and an appreciation for new ideas. The study had sufficient statistical power and measures were valid and reliable. The results confirm that those who habitually worry about the ecology are not only lacking in any psychopathology, but demonstrate a constructive and adaptive response to a serious problem. In the public domain, these findings may contribute to a more rational and less emotional debate on climate change and to the prevention of stigmatization of people who are genuinely concerned about our habitat and are prepared to do something about it ("habitual worriers are not crazy"). In the academic arena this study may contribute to environmental psychology ("habitual worrying is part of a green identity"), as well as to the literature on worry and anxiety ("habitual worrying can be a constructive response"). PMID:24023958

  8. Coralline algae (Rhodophyta) in a changing world: integrating ecological, physiological, and geochemical responses to global change.

    PubMed

    McCoy, Sophie J; Kamenos, Nicholas A

    2015-02-01

    Coralline algae are globally distributed benthic primary producers that secrete calcium carbonate skeletons. In the context of ocean acidification, they have received much recent attention due to the potential vulnerability of their high-Mg calcite skeletons and their many important ecological roles. Herein, we summarize what is known about coralline algal ecology and physiology, providing context to understand their responses to global climate change. We review the impacts of these changes, including ocean acidification, rising temperatures, and pollution, on coralline algal growth and calcification. We also assess the ongoing use of coralline algae as marine climate proxies via calibration of skeletal morphology and geochemistry to environmental conditions. Finally, we indicate critical gaps in our understanding of coralline algal calcification and physiology and highlight key areas for future research. These include analytical areas that recently have become more accessible, such as resolving phylogenetic relationships at all taxonomic ranks, elucidating the genes regulating algal photosynthesis and calcification, and calibrating skeletal geochemical metrics, as well as research directions that are broadly applicable to global change ecology, such as the importance of community-scale and long-term experiments in stress response. PMID:26986255

  9. Ecologic and symbiotic approaches to animal welfare, animal rights, and human responsibility.

    PubMed

    Kronfeld, D S; Parr, C P

    1987-09-15

    Veterinarians confronted with situations involving animal welfare, animal rights, and human responsibility assume practical importance in the relationships of veterinarians with clients and other constituencies. To help resolve these situations, the authors briefly compare economics and ethics and discuss the types of rights. An attempt is made to bring animal welfare and animal rights into the same conceptual framework, using an ecologic approach. This reaches the thesis that the less human beings allow animals the right of self-determination, the more we should exercise responsibility in their care and welfare. Actively exercised human responsibility in all uses of animals is offered as a practical and valid alternative to the extreme of abolitionism. This alternative also is applied in a cautionary way to the role of veterinary medicine in specieism. The veterinary profession is urged to be active in the middle ground of the field of animal rights and to firmly establish its relationships to animal welfare and human responsibility.

  10. Ecological considerations for the use of dispersants in oil spill response

    USGS Publications Warehouse

    Lindstedt-Siva, J.; Albers, P.H.; Fucik, K.W.; Maynard, N.G.; Allen, Tom E.

    1984-01-01

    A multidisciplinary task force with membership from government agencies, academia, and industry is developing ecologically based guidelines for dispersant use in marine and estuarine environments. The guidelines are organized by habitat type (e.g., coral reefs, rocky shores, bird habitats) and consider dispersant use to protect the habitats from impact, to mitigate impacts, and to clean the habitats after a spill. Each guideline contains a description of the habitat type covered, recommendations for dispersant use, and a background section reviewing the relevant literature. The goal is to minimize the ecological impacts of oil spills. Aesthetic, socioeconomic, and political factors are not considered, although it is recognized that these are important concerns during spill response. Use of dispersants is considered along with other appropriate countermeasures and compared with the “no cleanup” alternative.

  11. Ecological considerations for the use of dispersants in oil spill response

    SciTech Connect

    Lindstedt-Siva, J.; Albers, P.H.; Fucik, K.W.; Maynard, N.G.

    1982-10-01

    A multidisciplinary task force with membership from government agencies, academia, and industry is developing ecologically based guidelines for dispersant use in marine and estuarine environments. The guidelines are organized by habitat type (e.g., coral reefs, rocky shores, bird habitats) and consider dispersant use to protect the habitats from impact, to mitigate impacts, and to clean the habitats after a spill. Each guideline contains a description of the habitat type covered, recommendations for dispersant use, and a background section reviewing the relevant literature. The goal is to minimize the ecological impacts of oil spills. Aesthetic, socioeconomic, and political factors are not considered, although it is recognized that these are important concerns during spill response. Use of dispersants is considered along with other appropriate countermeasures and compared with the ''no cleanup'' alternative.

  12. Exploring the universal ecological responses to climate change in a univoltine butterfly.

    PubMed

    Fenberg, Phillip B; Self, Angela; Stewart, John R; Wilson, Rebecca J; Brooks, Stephen J

    2016-05-01

    Animals with distinct life stages are often exposed to different temperatures during each stage. Thus, how temperature affects these life stages should be considered for broadly understanding the ecological consequences of climate warming on such species. For example, temperature variation during particular life stages may affect respective change in body size, phenology and geographic range, which have been identified as the "universal" ecological responses to climate change. While each of these responses has been separately documented across a number of species, it is not known whether each response occurs together within a species. The influence of temperature during particular life stages may help explain each of these ecological responses to climate change. Our goal was to determine if monthly temperature variation during particular life stages of a butterfly species can predict respective changes in body size and phenology. We also refer to the literature to assess if temperature variability during the adult stage influences range change over time. Using historical museum collections paired with monthly temperature records, we show that changes in body size and phenology of the univoltine butterfly, Hesperia comma, are partly dependent upon temporal variation in summer temperatures during key stages of their life cycle. June temperatures, which are likely to affect growth rate of the final larval instar, are important for predicting adult body size (for males only; showing a positive relationship with temperature). July temperatures, which are likely to influence the pupal stage, are important for predicting the timing of adult emergence (showing a negative relationship with temperature). Previous studies show that August temperatures, which act on the adult stage, are linked to range change. Our study highlights the importance of considering temperature variation during each life stage over historic time-scales for understanding intraspecific response to

  13. Electrically Responsive Surfaces: Experimental and Theoretical Investigations

    PubMed Central

    2016-01-01

    Conspectus Stimuli-responsive surfaces have sparked considerable interest in recent years, especially in view of their biomimetic nature and widespread biomedical applications. Significant efforts are continuously being directed at developing functional surfaces exhibiting specific property changes triggered by variations in electrical potential, temperature, pH and concentration, irradiation with light, or exposure to a magnetic field. In this respect, electrical stimulus offers several attractive features, including a high level of spatial and temporal controllability, rapid and reverse inducement, and noninvasiveness. In this Account, we discuss how surfaces can be designed and methodologies developed to produce electrically switchable systems, based on research by our groups. We aim to provide fundamental mechanistic and structural features of these dynamic systems, while highlighting their capabilities and potential applications. We begin by briefly describing the current state-of-the-art in integrating electroactive species on surfaces to control the immobilization of diverse biological entities. This premise leads us to portray our electrically switchable surfaces, capable of controlling nonspecific and specific biological interactions by exploiting molecular motions of surface-bound electroswitchable molecules. We demonstrate that our self-assembled monolayer-based electrically switchable surfaces can modulate the interactions of surfaces with proteins, mammalian and bacterial cells. We emphasize how these systems are ubiquitous in both switching biomolecular interactions in highly complex biological conditions while still offering antifouling properties. We also introduce how novel characterization techniques, such as surface sensitive vibrational sum-frequency generation (SFG) spectroscopy, can be used for probing the electrically switchable molecular surfaces in situ. SFG spectroscopy is a technique that not only allowed determining the structural

  14. Application of microcosmic system for assessment of insecticide effects on biomarker responses in ecologically different earthworm species.

    PubMed

    Velki, Mirna; Hackenberger, Branimir K; Lončarić, Zeljka; Hackenberger, Davorka K

    2014-06-01

    Earthworms from different ecological categories--epigeic Eisenia andrei and Lumbricus rubellus, endogeic Octolasion lacteum and anecic Lumbricus terrestris--were exposed in a microcosmic system to three commonly used insecticides. The effects of the insecticides were evaluated by measuring the following molecular biomarkers-the activities of AChE, CES, CAT, GST and the concentration of GSH. The results showed that environmentally relevant doses of organophosphates dimethoate and pirimiphos-methyl significantly affected the measured biomarkers, whereas pyrethroid deltamethrin did not affect the earthworms at the recommended agricultural dose. Considering the ecological category of earthworms, the results were inhomogeneous and species-specific differences in the biomarker responses were recorded. Since the biomarker responses of the investigated earthworm species were different after exposure to organophosphates in a microcosm compared to the exposure via standardized toxicity tests, two types of species sensitivity should be distinguished-physiological and environmental sensitivity. In addition, the hormetic effect of organophosphates on AChE and CES activities was recorded. The detection of hormesis in a microcosm is of great importance for future environmental research and soil biomonitoring, since in a realistic environment pollutants usually occur at low concentrations that could cause a hormetic effect. The results demonstrate the importance of the application of microcosmic systems in the assessment of the effects of environmental pollutants and the necessity of taking into account the possible differences between physiological and environmental species sensitivity.

  15. Application of microcosmic system for assessment of insecticide effects on biomarker responses in ecologically different earthworm species.

    PubMed

    Velki, Mirna; Hackenberger, Branimir K; Lončarić, Zeljka; Hackenberger, Davorka K

    2014-06-01

    Earthworms from different ecological categories--epigeic Eisenia andrei and Lumbricus rubellus, endogeic Octolasion lacteum and anecic Lumbricus terrestris--were exposed in a microcosmic system to three commonly used insecticides. The effects of the insecticides were evaluated by measuring the following molecular biomarkers-the activities of AChE, CES, CAT, GST and the concentration of GSH. The results showed that environmentally relevant doses of organophosphates dimethoate and pirimiphos-methyl significantly affected the measured biomarkers, whereas pyrethroid deltamethrin did not affect the earthworms at the recommended agricultural dose. Considering the ecological category of earthworms, the results were inhomogeneous and species-specific differences in the biomarker responses were recorded. Since the biomarker responses of the investigated earthworm species were different after exposure to organophosphates in a microcosm compared to the exposure via standardized toxicity tests, two types of species sensitivity should be distinguished-physiological and environmental sensitivity. In addition, the hormetic effect of organophosphates on AChE and CES activities was recorded. The detection of hormesis in a microcosm is of great importance for future environmental research and soil biomonitoring, since in a realistic environment pollutants usually occur at low concentrations that could cause a hormetic effect. The results demonstrate the importance of the application of microcosmic systems in the assessment of the effects of environmental pollutants and the necessity of taking into account the possible differences between physiological and environmental species sensitivity. PMID:24650551

  16. Indigenous Knowledge and Long-term Ecological Change: Detection, Interpretation, and Responses to Changing Ecological Conditions in Pacific Island Communities

    PubMed Central

    Aswani, Shankar

    2010-01-01

    When local resource users detect, understand, and respond to environmental change they can more effectively manage environmental resources. This article assesses these abilities among artisanal fishers in Roviana Lagoon, Solomon Islands. In a comparison of two villages, it documents local resource users’ abilities to monitor long-term ecological change occurring to seagrass meadows near their communities, their understandings of the drivers of change, and their conceptualizations of seagrass ecology. Local observations of ecological change are compared with historical aerial photography and IKONOS satellite images that show 56 years of actual changes in seagrass meadows from 1947 to 2003. Results suggest that villagers detect long-term changes in the spatial cover of rapidly expanding seagrass meadows. However, for seagrass meadows that showed no long-term expansion or contraction in spatial cover over one-third of respondents incorrectly assumed changes had occurred. Examples from a community-based management initiative designed around indigenous ecological knowledge and customary sea tenure governance show how local observations of ecological change shape marine resource use and practices which, in turn, can increase the management adaptability of indigenous or hybrid governance systems. PMID:20336296

  17. Approaches to investigating the ecology of plasmids in marine bacterial communities.

    PubMed

    Sobecky, Patricia A

    2002-11-01

    To better understand prokaryotic gene flux in marine ecosystems and to determine whether or not environmental parameters can effect the composition and structure of plasmid populations in marine bacterial communities, information on the distribution, diversity, and ecological traits of marine plasmids is necessary. This mini-review highlights recent insights gained into the molecular diversity and ecology of plasmids occurring in marine microbial communities.

  18. Neural responses to sounds presented on and off the beat of ecologically valid music.

    PubMed

    Tierney, Adam; Kraus, Nina

    2013-01-01

    The tracking of rhythmic structure is a vital component of speech and music perception. It is known that sequences of identical sounds can give rise to the percept of alternating strong and weak sounds, and that this percept is linked to enhanced cortical and oscillatory responses. The neural correlates of the perception of rhythm elicited by ecologically valid, complex stimuli, however, remain unexplored. Here we report the effects of a stimulus' alignment with the beat on the brain's processing of sound. Human subjects listened to short popular music pieces while simultaneously hearing a target sound. Cortical and brainstem electrophysiological onset responses to the sound were enhanced when it was presented on the beat of the music, as opposed to shifted away from it. Moreover, the size of the effect of alignment with the beat on the cortical response correlated strongly with the ability to tap to a beat, suggesting that the ability to synchronize to the beat of simple isochronous stimuli and the ability to track the beat of complex, ecologically valid stimuli may rely on overlapping neural resources. These results suggest that the perception of musical rhythm may have robust effects on processing throughout the auditory system. PMID:23717268

  19. An ecological response model for the Cache la Poudre River through Fort Collins

    USGS Publications Warehouse

    Shanahan, Jennifer; Baker, Daniel; Bledsoe, Brian P.; Poff, LeRoy; Merritt, David M.; Bestgen, Kevin R.; Auble, Gregor T.; Kondratieff, Boris C.; Stokes, John; Lorie, Mark; Sanderson, John

    2014-01-01

    The ERM was designed to represent the multi-dimensional ecological character of the contemporary urban Poudre River. It provides a scientific foundation that can serve as a decision support tool and foster a more informed community discussion about the future of the river as it provides a better understanding of the likely response of the Poudre River ecosystem to environmental flow management and other stewardship activities. In particular, model results can assist managers in developing specific management actions to achieve desirable goals for key indicators of river health.

  20. Community responses to contaminants: using basic ecological principles to predict ecotoxicological effects.

    PubMed

    Clements, William H; Rohr, Jason R

    2009-09-01

    Community ecotoxicology is defined as the study of the effects of contaminants on patterns of species abundance, diversity, community composition, and species interactions. Recent discoveries that species diversity is positively associated with ecosystem stability, recovery, and services have made a community-level perspective on ecotoxicology more important than ever. Community ecotoxicology must explicitly consider both present and impending global change and shift from a purely descriptive to a more predictive science. Greater consideration of the ecological factors and threshold responses that determine community resistance and resilience should improve our ability to predict how and when communities will respond to, and recover from, xenobiotics. A better understanding of pollution-induced community tolerance, and of the costs of this tolerance, should facilitate identifying contaminant-impacted communities, thus forecasting the ecological consequences of contaminant exposure and determining the restoration effectiveness. Given the vast complexity of community ecotoxicology, simplifying assumptions, such as the possibility that the approximately 100,000 registered chemicals could be reduced to a more manageable number of contaminant classes with similar modes of action, must be identified and validated. In addition to providing a framework for predicting contaminant fate and effects, food-web ecology can help to identify communities that are sensitive to contaminants, contaminants that are particularly insidious to communities, and species that are crucial for transmitting adverse effects across trophic levels. Integration of basic ecological principles into the design and implementation of ecotoxicological research is essential for predicting contaminant effects within the context of rapidly changing, global environmental conditions. PMID:19358627

  1. 21 CFR 312.60 - General responsibilities of investigators.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 5 2010-04-01 2010-04-01 false General responsibilities of investigators. 312.60 Section 312.60 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE INVESTIGATIONAL NEW DRUG APPLICATION Responsibilities of Sponsors...

  2. Nanoindentation of lemur enamel: an ecological investigation of mechanical property variations within and between sympatric species.

    PubMed

    Campbell, Sara E; Cuozzo, Frank P; Sauther, Michelle L; Sponheimer, Matt; Ferguson, Virginia L

    2012-06-01

    The common morphological metrics of size, shape, and enamel thickness of teeth are believed to reflect the functional requirements of a primate's diet. However, the mechanical and material properties of enamel also contribute to tooth function, yet are rarely studied. Substantial wear and tooth loss previously documented in Lemur catta at the Beza Mahafaly Special Reserve suggests that their dental morphology, structure, and possibly their enamel are not adapted for their current fallback food (the mechanically challenging tamarind fruit). In this study, we investigate the nanomechanical properties, mineralization, and microstructure of the enamel of three sympatric lemur species to provide insight into their dietary functional adaptations. Mechanical properties measured by nanoindentation were compared to measurements of mineral content, prism orientation, prism size, and enamel thickness using electron microscopy. Mechanical properties of all species were similar near the enamel dentin junction and variations correlated with changes in microstructure (e.g., prism size) and mineral content. Severe wear and microcracking within L. catta's enamel were associated with up to a 43% reduction in nanomechanical properties in regions of cracking versus intact enamel. The mechanical and material properties of L. catta's enamel are similar to those of sympatric folivores and suggest that they are not uniquely mechanically adapted to consume the physically challenging tamarind fruit. An understanding of the material and mechanical properties of enamel is required to fully elucidate the functional and ecological adaptations of primate teeth.

  3. An initial investigation into the ecology of culturable aerobic postmortem bacteria.

    PubMed

    Chun, Lauren P; Miguel, Marcus J; Junkins, Emily N; Forbes, Shari L; Carter, David O

    2015-12-01

    Postmortem microorganisms are increasingly recognized for their potential to serve as physical evidence. Yet, we still understand little about the ecology of postmortem microbes, particularly those associated with the skin and larval masses. We conducted an experiment to characterize microbiological and chemical properties of decomposing swine (Sus scrofa domesticus) carcasses on the island of Oahu, Hawaii, USA, during June 2013. Bacteria were collected from the head, limb, and larval mass during the initial 145h of decomposition. We also measured the pH, temperature, and oxidation-reduction potential of larval masses in situ. Bacteria were cultured aerobically on Standard Nutrient Agar at 22°C and identified using protein or genetic signals. Carcass decomposition followed a typical sigmoidal pattern and associated bacterial communities differed by sampling location and time since death, although all communities were dominated by phyla Actinobacteria, Firmicutes, and Proteobacteria. Larval masses were reducing environments (~-200mV) of neutral pH (6.5-7.5) and high temperature (35°C-40°C). We recommend that culturable postmortem and larval mass microbiology and chemistry be investigated in more detail, as it has potential to complement culture-independent studies and serve as a rapid estimate of PMI. PMID:26654073

  4. Nanoindentation of lemur enamel: an ecological investigation of mechanical property variations within and between sympatric species.

    PubMed

    Campbell, Sara E; Cuozzo, Frank P; Sauther, Michelle L; Sponheimer, Matt; Ferguson, Virginia L

    2012-06-01

    The common morphological metrics of size, shape, and enamel thickness of teeth are believed to reflect the functional requirements of a primate's diet. However, the mechanical and material properties of enamel also contribute to tooth function, yet are rarely studied. Substantial wear and tooth loss previously documented in Lemur catta at the Beza Mahafaly Special Reserve suggests that their dental morphology, structure, and possibly their enamel are not adapted for their current fallback food (the mechanically challenging tamarind fruit). In this study, we investigate the nanomechanical properties, mineralization, and microstructure of the enamel of three sympatric lemur species to provide insight into their dietary functional adaptations. Mechanical properties measured by nanoindentation were compared to measurements of mineral content, prism orientation, prism size, and enamel thickness using electron microscopy. Mechanical properties of all species were similar near the enamel dentin junction and variations correlated with changes in microstructure (e.g., prism size) and mineral content. Severe wear and microcracking within L. catta's enamel were associated with up to a 43% reduction in nanomechanical properties in regions of cracking versus intact enamel. The mechanical and material properties of L. catta's enamel are similar to those of sympatric folivores and suggest that they are not uniquely mechanically adapted to consume the physically challenging tamarind fruit. An understanding of the material and mechanical properties of enamel is required to fully elucidate the functional and ecological adaptations of primate teeth. PMID:22610894

  5. The ecology of host immune responses to chronic avian haemosporidian infection.

    PubMed

    Ellis, Vincenzo A; Kunkel, Melanie R; Ricklefs, Robert E

    2014-11-01

    Host responses to parasitism in the wild are often studied in the context of single host-parasite systems, which provide little insight into the ecological dynamics of host-parasite interactions within a community. Here we characterized immune system responses to mostly low-intensity, chronic infection by haemosporidian parasites in a sample of 424 individuals of 22 avian host species from the same local assemblage in the Missouri Ozarks. Two types of white blood cells (heterophils and lymphocytes) were elevated in infected individuals across species, as was the acute-phase protein haptoglobin, which is associated with inflammatory immune responses. Linear discriminant analysis indicated that individuals infected by haemosporidians occupied a subset of the overall white blood cell multivariate space that was also occupied by uninfected individuals, suggesting that these latter individuals might have harbored other pathogens or that parasites more readily infect individuals with a specific white blood cell profile. DNA sequence-defined lineages of haemosporidian parasites were sparsely distributed across the assemblage of hosts. In one well-sampled host species, the red-eyed vireo (Vireo olivaceus), heterophils were significantly elevated in individuals infected with one but not another of two common parasite lineages. Another well-sampled host, the yellow-breasted chat (Icteria virens), exhibited no differences in immune response to different haemosporidian lineages. Our results indicate that while immune responses to infection may be generalized across host species, parasite-specific immune responses may also occur. PMID:25179282

  6. Response diversity can increase ecological resilience to disturbance in coral reefs.

    PubMed

    Baskett, Marissa L; Fabina, Nicholas S; Gross, Kevin

    2014-08-01

    Community-level resilience depends on the interaction between multiple populations that vary in individual responses to disturbance. For example, in tropical reefs, some corals can survive higher stress (resistance) while others exhibit faster recovery (engineering resilience) following disturbances such as thermal stress. While each type will negatively affect the other through competition, each might also benefit the other by reducing the potential for an additional competitor such as macroalgae to invade after a disturbance. To determine how community composition affects ecological resilience, we modeled coral-macroalgae interactions given either a resistant coral, a resilient coral, or both together. Having both coral types (i.e., response diversity) can lead to observable enhanced ecological resilience if (1) the resilient coral is not a superior competitor and (2) disturbance levels are high enough such that the resilient coral would collapse when considered alone. This enhanced resilience occurs through competitor-enabled rescue where each coral increases the potential for the other to recover from disturbance through external recruitment, such that both corals benefit from the presence of each other in terms of total cover and resilience. Therefore, conservation management aimed at protecting resilience under global change requires consideration of both diversity and connectivity between sites experiencing differential disturbance. PMID:25058289

  7. Predicting Ecological Responses of the Florida Everglades to Possible Future Climate Scenarios: Introduction

    NASA Astrophysics Data System (ADS)

    Aumen, Nicholas G.; Havens, Karl E.; Best, G. Ronnie; Berry, Leonard

    2015-04-01

    Florida's Everglades stretch from the headwaters of the Kissimmee River near Orlando to Florida Bay. Under natural conditions in this flat landscape, water flowed slowly downstream as broad, shallow sheet flow. The ecosystem is markedly different now, altered by nutrient pollution and construction of canals, levees, and water control structures designed for flood control and water supply. These alterations have resulted in a 50 % reduction of the ecosystem's spatial extent and significant changes in ecological function in the remaining portion. One of the world's largest restoration programs is underway to restore some of the historic hydrologic and ecological functions of the Everglades, via a multi-billion dollar Comprehensive Everglades Restoration Plan. This plan, finalized in 2000, did not explicitly consider climate change effects, yet today we realize that sea level rise and future changes in rainfall (RF), temperature, and evapotranspiration (ET) may have system-wide impacts. This series of papers describes results of a workshop where a regional hydrologic model was used to simulate the hydrology expected in 2060 with climate changes including increased temperature, ET, and sea level, and either an increase or decrease in RF. Ecologists with expertise in various areas of the ecosystem evaluated the hydrologic outputs, drew conclusions about potential ecosystem responses, and identified research needs where projections of response had high uncertainty. Resource managers participated in the workshop, and they present lessons learned regarding how the new information might be used to guide Everglades restoration in the context of climate change.

  8. Response diversity can increase ecological resilience to disturbance in coral reefs.

    PubMed

    Baskett, Marissa L; Fabina, Nicholas S; Gross, Kevin

    2014-08-01

    Community-level resilience depends on the interaction between multiple populations that vary in individual responses to disturbance. For example, in tropical reefs, some corals can survive higher stress (resistance) while others exhibit faster recovery (engineering resilience) following disturbances such as thermal stress. While each type will negatively affect the other through competition, each might also benefit the other by reducing the potential for an additional competitor such as macroalgae to invade after a disturbance. To determine how community composition affects ecological resilience, we modeled coral-macroalgae interactions given either a resistant coral, a resilient coral, or both together. Having both coral types (i.e., response diversity) can lead to observable enhanced ecological resilience if (1) the resilient coral is not a superior competitor and (2) disturbance levels are high enough such that the resilient coral would collapse when considered alone. This enhanced resilience occurs through competitor-enabled rescue where each coral increases the potential for the other to recover from disturbance through external recruitment, such that both corals benefit from the presence of each other in terms of total cover and resilience. Therefore, conservation management aimed at protecting resilience under global change requires consideration of both diversity and connectivity between sites experiencing differential disturbance.

  9. Predicting ecological responses of the Florida Everglades to possible future climate scenarios: introduction.

    PubMed

    Aumen, Nicholas G; Havens, Karl E; Best, G Ronnie; Berry, Leonard

    2015-04-01

    Florida's Everglades stretch from the headwaters of the Kissimmee River near Orlando to Florida Bay. Under natural conditions in this flat landscape, water flowed slowly downstream as broad, shallow sheet flow. The ecosystem is markedly different now, altered by nutrient pollution and construction of canals, levees, and water control structures designed for flood control and water supply. These alterations have resulted in a 50% reduction of the ecosystem's spatial extent and significant changes in ecological function in the remaining portion. One of the world's largest restoration programs is underway to restore some of the historic hydrologic and ecological functions of the Everglades, via a multi-billion dollar Comprehensive Everglades Restoration Plan. This plan, finalized in 2000, did not explicitly consider climate change effects, yet today we realize that sea level rise and future changes in rainfall (RF), temperature, and evapotranspiration (ET) may have system-wide impacts. This series of papers describes results of a workshop where a regional hydrologic model was used to simulate the hydrology expected in 2060 with climate changes including increased temperature, ET, and sea level, and either an increase or decrease in RF. Ecologists with expertise in various areas of the ecosystem evaluated the hydrologic outputs, drew conclusions about potential ecosystem responses, and identified research needs where projections of response had high uncertainty. Resource managers participated in the workshop, and they present lessons learned regarding how the new information might be used to guide Everglades restoration in the context of climate change.

  10. Predicting ecological responses of the Florida Everglades to possible future climate scenarios: introduction.

    PubMed

    Aumen, Nicholas G; Havens, Karl E; Best, G Ronnie; Berry, Leonard

    2015-04-01

    Florida's Everglades stretch from the headwaters of the Kissimmee River near Orlando to Florida Bay. Under natural conditions in this flat landscape, water flowed slowly downstream as broad, shallow sheet flow. The ecosystem is markedly different now, altered by nutrient pollution and construction of canals, levees, and water control structures designed for flood control and water supply. These alterations have resulted in a 50% reduction of the ecosystem's spatial extent and significant changes in ecological function in the remaining portion. One of the world's largest restoration programs is underway to restore some of the historic hydrologic and ecological functions of the Everglades, via a multi-billion dollar Comprehensive Everglades Restoration Plan. This plan, finalized in 2000, did not explicitly consider climate change effects, yet today we realize that sea level rise and future changes in rainfall (RF), temperature, and evapotranspiration (ET) may have system-wide impacts. This series of papers describes results of a workshop where a regional hydrologic model was used to simulate the hydrology expected in 2060 with climate changes including increased temperature, ET, and sea level, and either an increase or decrease in RF. Ecologists with expertise in various areas of the ecosystem evaluated the hydrologic outputs, drew conclusions about potential ecosystem responses, and identified research needs where projections of response had high uncertainty. Resource managers participated in the workshop, and they present lessons learned regarding how the new information might be used to guide Everglades restoration in the context of climate change. PMID:25743272

  11. Turning on the heat: ecological response to simulated warming in the sea.

    PubMed

    Smale, Dan A; Wernberg, Thomas; Peck, Lloyd S; Barnes, David K A

    2011-01-14

    Significant warming has been observed in every ocean, yet our ability to predict the consequences of oceanic warming on marine biodiversity remains poor. Experiments have been severely limited because, until now, it has not been possible to manipulate seawater temperature in a consistent manner across a range of marine habitats. We constructed a "hot-plate" system to directly examine ecological responses to elevated seawater temperature in a subtidal marine system. The substratum available for colonisation and overlying seawater boundary layer were warmed for 36 days, which resulted in greater biomass of marine organisms and a doubling of space coverage by a dominant colonial ascidian. The "hot-plate" system will facilitate complex manipulations of temperature and multiple stressors in the field to provide valuable information on the response of individuals, populations and communities to environmental change in any aquatic habitat.

  12. Investigation of air cleaning system response to accident conditions

    SciTech Connect

    Andrae, R.W.; Bolstad, J.W.; Foster, R.D.; Gregory, W.S.; Horak, H.L.; Idar, E.S.; Martin, R.A.; Ricketts, C.I.; Smith, P.R.; Tang, P.K.

    1980-01-01

    Air cleaning system response to the stress of accident conditions are being investigated. A program overview and hghlight recent results of our investigation are presented. The program includes both analytical and experimental investigations. Computer codes for predicting effects of tornados, explosions, fires, and material transport are described. The test facilities used to obtain supportive experimental data to define structural integrity and confinement effectiveness of ventilation system components are described. Examples of experimental results for code verification, blower response to tornado transients, and filter response to tornado and explosion transients are reported.

  13. Toward an ecological analysis of Bayesian inferences: how task characteristics influence responses

    PubMed Central

    Hafenbrädl, Sebastian; Hoffrage, Ulrich

    2015-01-01

    In research on Bayesian inferences, the specific tasks, with their narratives and characteristics, are typically seen as exchangeable vehicles that merely transport the structure of the problem to research participants. In the present paper, we explore whether, and possibly how, task characteristics that are usually ignored influence participants’ responses in these tasks. We focus on both quantitative dimensions of the tasks, such as their base rates, hit rates, and false-alarm rates, as well as qualitative characteristics, such as whether the task involves a norm violation or not, whether the stakes are high or low, and whether the focus is on the individual case or on the numbers. Using a data set of 19 different tasks presented to 500 different participants who provided a total of 1,773 responses, we analyze these responses in two ways: first, on the level of the numerical estimates themselves, and second, on the level of various response strategies, Bayesian and non-Bayesian, that might have produced the estimates. We identified various contingencies, and most of the task characteristics had an influence on participants’ responses. Typically, this influence has been stronger when the numerical information in the tasks was presented in terms of probabilities or percentages, compared to natural frequencies – and this effect cannot be fully explained by a higher proportion of Bayesian responses when natural frequencies were used. One characteristic that did not seem to influence participants’ response strategy was the numerical value of the Bayesian solution itself. Our exploratory study is a first step toward an ecological analysis of Bayesian inferences, and highlights new avenues for future research. PMID:26300791

  14. A Cognitive Ecological Model of Women’s Response to Male Sexual Coercion in Dating

    PubMed Central

    Nurius, Paula S.; Norris, Jeanette

    2015-01-01

    SUMMARY We offer a theoretical model that consolidates background, environmental, and intrapersonal variables related to women’s experience of sexual coercion in dating into a coherent ecological framework and present for the first time a cognitive analysis of the processes women use to formulate responses to sexual coercion. An underlying premise for this model is that a woman’s coping response to sexual coercion by an acquaintance is mediated through cognitive processing of background and situational influences. Because women encounter this form of sexual coercion in the context of relationships and situations that they presume will follow normative expectations (e.g., about making friends, socializing and dating), it is essential to consider normative processes of learning, cognitive mediation, and coping guiding their efforts to interpret and respond to this form of personal threat. Although acts of coercion unquestionably remain the responsibility of the perpetrator, a more complete understanding of the multilevel factors shaping women’s perception of and response to threats can strengthen future inquiry and prevention efforts. PMID:25729157

  15. Investigating the LGBTQ Responsive Model for Supervision of Group Work

    ERIC Educational Resources Information Center

    Luke, Melissa; Goodrich, Kristopher M.

    2013-01-01

    This article reports an investigation of the LGBTQ Responsive Model for Supervision of Group Work, a trans-theoretical supervisory framework to address the needs of lesbian, gay, bisexual, transgender, and questioning (LGBTQ) persons (Goodrich & Luke, 2011). Findings partially supported applicability of the LGBTQ Responsive Model for Supervision…

  16. Ecological responses to experimental glacier-runoff reduction in alpine rivers

    NASA Astrophysics Data System (ADS)

    Cauvy-Fraunié, Sophie; Andino, Patricio; Espinosa, Rodrigo; Calvez, Roger; Jacobsen, Dean; Dangles, Olivier

    2016-06-01

    Glacier retreat is a worldwide phenomenon with important consequences for the hydrological cycle and downstream ecosystem structure and functioning. To determine the effects of glacier retreat on aquatic communities, we conducted a 4-year flow manipulation in a tropical glacier-fed stream. Compared with an adjacent reference stream, meltwater flow reduction induces significant changes in benthic fauna community composition in less than 2 weeks. Also, both algal and herbivore biomass significantly increase in the manipulated stream as a response to flow reduction. After the flow reduction ceased, the system requires 14-16 months to return to its pre-perturbation state. These results are supported by a multi-stream survey of sites varying in glacial influence, showing an abrupt increase in algal and herbivore biomass below 11% glacier cover in the catchment. This study shows that flow reduction strongly affects glacier-fed stream biota, prefiguring profound ecological effects of ongoing glacier retreat on aquatic systems.

  17. Ecological responses to experimental glacier-runoff reduction in alpine rivers

    PubMed Central

    Cauvy-Fraunié, Sophie; Andino, Patricio; Espinosa, Rodrigo; Calvez, Roger; Jacobsen, Dean; Dangles, Olivier

    2016-01-01

    Glacier retreat is a worldwide phenomenon with important consequences for the hydrological cycle and downstream ecosystem structure and functioning. To determine the effects of glacier retreat on aquatic communities, we conducted a 4-year flow manipulation in a tropical glacier-fed stream. Compared with an adjacent reference stream, meltwater flow reduction induces significant changes in benthic fauna community composition in less than 2 weeks. Also, both algal and herbivore biomass significantly increase in the manipulated stream as a response to flow reduction. After the flow reduction ceased, the system requires 14–16 months to return to its pre-perturbation state. These results are supported by a multi-stream survey of sites varying in glacial influence, showing an abrupt increase in algal and herbivore biomass below 11% glacier cover in the catchment. This study shows that flow reduction strongly affects glacier-fed stream biota, prefiguring profound ecological effects of ongoing glacier retreat on aquatic systems. PMID:27338650

  18. Consequences of ecological, evolutionary and biogeochemical uncertainty for coral reef responses to climatic stress.

    PubMed

    Mumby, Peter J; van Woesik, Robert

    2014-05-19

    Coral reefs are highly sensitive to the stress associated with greenhouse gas emissions, in particular ocean warming and acidification. While experiments show negative responses of most reef organisms to ocean warming, some autotrophs benefit from ocean acidification. Yet, we are uncertain of the response of coral reefs as systems. We begin by reviewing sources of uncertainty and complexity including the translation of physiological effects into demographic processes, indirect ecological interactions among species, the ability of coral reefs to modify their own chemistry, adaptation and trans-generational plasticity. We then incorporate these uncertainties into two simple qualitative models of a coral reef system under climate change. Some sources of uncertainty are far more problematic than others. Climate change is predicted to have an unambiguous negative effect on corals that is robust to several sources of uncertainty but sensitive to the degree of biogeochemical coupling between benthos and seawater. Macroalgal, zoanthid, and herbivorous fish populations are generally predicted to increase, but the ambiguity (confidence) of such predictions are sensitive to the source of uncertainty. For example, reversing the effect of climate-related stress on macroalgae from being positive to negative had no influence on system behaviour. By contrast, the system was highly sensitive to a change in the stress upon herbivorous fishes. Minor changes in competitive interactions had profound impacts on system behaviour, implying that the outcomes of mesocosm studies could be highly sensitive to the choice of taxa. We use our analysis to identify new hypotheses and suggest that the effects of climatic stress on coral reefs provide an exceptional opportunity to test emerging theories of ecological inheritance.

  19. Identifying Droughts by Modeling the Hydrologic and Ecologic Responses in the Medjerda River Basin, Tunisia

    NASA Astrophysics Data System (ADS)

    Sawada, Y.; Koike, T.; Jaranilla-sanchez, P. A.

    2013-12-01

    Drought brings severe damage to water and agricultural resources, and both of hydrological and ecological responses are important for understanding droughts. However, the ecological contributions to drought characteristics at the basin scale have not been quantified. To address this issue, we developed an eco-hydrological model that can calculate vegetation dynamics as a diagnostic valuable in a distributed-hydrological modeling framework and identified different drought types in the Medjerda River Basin where drought is a predominant issue. From the inputs and outputs of the model, we calculate drought indices for different drought types. The model shows reliable accuracy in reproducing the observed river discharge and the satellite observed leaf area index in the long-term (19-year) simulation. Moreover, the drought index calculated from model estimated annual peak of leaf area index is well correlated (correlation coefficient; r = 0.89; see Figure) with drought index from nationwide annual crop production, which show the modeled leaf area index has enough capacity to reproducing agricultural droughts that can be related with historical food shortage on 1988-1989 and 1993-1995. Our model can estimate vegetation dynamics and water cycle simultaneously in the enough accuracy to analyze the basin-scale agricultural and hydrological droughts separately. We clarify that vegetation dynamics has quicker response to meteorological droughts than river discharge and groundwater dynamics in Medjerda River Basin because vegetation dynamics is sensitive to soil moisture in surface layers while soil moisture in deeper layers strongly contributes to stream flow and depth of groundwater level. Therefore, historical agricultural droughts predominantly occurred prior to hydrological droughts and in the 1988-1989 drought, the hydrological drought lasted much longer even after crop production recovered. Standardized anomaly index (SA) for estimated annual maximum leaf area index

  20. An Investigation of the Ecological and Social Impacts Caused by Rock Climbers.

    ERIC Educational Resources Information Center

    Attarian, Aram

    This study examined the ecological and social impacts of rock climbing. The survey included climbing sites in 10 federal areas, 2 state parks, 1 private area, and 1 city park. Resource managers provided information on the observed impacts of rock climbing and current management practices to minimize impacts. Survey results indicate: (1) 71 percent…

  1. The Use of the Mounds of Lasius flavus in Teaching Some Principles of Ecological Investigation

    ERIC Educational Resources Information Center

    King, T. J.; Woodell, S. R. J.

    1975-01-01

    Outlines the ecology of Lasius flavus ant hill, describes sampling techniques for the determination of the species composition of the surrounding vegetation, presents a table of typical results from an ant-hill practical, and lists suggestions for further experiments. (GS)

  2. 32 CFR 536.22 - Claims investigative responsibility-General.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 3 2010-07-01 2010-07-01 true Claims investigative responsibility-General. 536.22 Section 536.22 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY CLAIMS AND ACCOUNTS CLAIMS AGAINST THE UNITED STATES Investigation and Processing of Claims § 536.22...

  3. 32 CFR 536.24 - Delegation of investigative responsibility.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 3 2010-07-01 2010-07-01 true Delegation of investigative responsibility. 536.24 Section 536.24 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY CLAIMS AND ACCOUNTS CLAIMS AGAINST THE UNITED STATES Investigation and Processing of Claims §...

  4. Rapid Ecological Change in Two Contrasting Lake Ecosystems: Evidence of Threshold Responses, Altered Species Dynamics, and Perturbed Patterns of Variability

    NASA Astrophysics Data System (ADS)

    Simpson, G. L.

    2015-12-01

    Studying threshold responses to environmental change is often made difficult due to the paucity of monitoring data prior to and during change. Progress has been made via theoretical models of regime shifts or experimental manipulation but natural, real world, examples of threshold change are limited and in many cases inconclusive. Lake sediments provide the potential to examine abrupt ecological change by directly observing how species, communities, and biogeochemical proxies responded to environmental perturbation or recorded ecosystem change. These records are not problem-free; age uncertainties, uneven and variable temporal resolution, and time-consuming taxonomic work all act to limit the scope and scale of the data or complicate its analysis. Here I use two annually laminated records 1. Kassjön, a seasonally anoxic mesotrophic lake in N Sweden, and2. Baldeggersee, a nutrient rich, hardwater lake on the central Swiss Plateau to investigate lake ecosystem responses to abrupt environmental change using ideal paleoecological time series. Rapid cooling 2.2kyr ago in northern Sweden significantly perturbed the diatom community of Kassjön. Using wavelet analysis, this amelioration in climate also fundamentally altered patterns of variance in diatom abundances, suppressing cyclicity in species composition that required several hundred years to reestablish. Multivariate wavelet analysis of the record showed marked switching between synchronous and asynchronous species dynamics in response to rapid climatic cooling and subsequent warming. Baldeggersee has experienced a long history of eutrophication and the diatom record has been used as a classic illustration of a regime shift in response to nutrient loading. Time series analysis of the record identified some evidence of a threshold-like response in the diatoms. A stochastic volatility model identified increasing variance in composition prior to the threshold, as predicted from theory, and a switch from compensatory

  5. How groups cope with collective responsibility for ecological problems: Symbolic coping and collective emotions.

    PubMed

    Caillaud, Sabine; Bonnot, Virginie; Ratiu, Eugenia; Krauth-Gruber, Silvia

    2016-06-01

    This study explores the way groups cope with collective responsibility for ecological problems. The social representations approach was adopted, and the collective symbolic coping model was used as a frame of analysis, integrating collective emotions to enhance the understanding of coping processes. The original feature of this study is that the analysis is at group level. Seven focus groups were conducted with French students. An original use of focus groups was proposed: Discussions were structured to induce feelings of collective responsibility and enable observation of how groups cope with such feelings at various levels (social knowledge; social identities; group dynamics). Two analyses were conducted: Qualitative analysis of participants' use of various kinds of knowledge, social categories and the group dynamics, and lexicometric analysis to reveal how emotions varied during the different discussion phases. Results showed that groups' emotional states moved from negative to positive: They used specific social categories and resorted to shared stereotypes to cope with collective responsibility and maintain the integrity of their worldview. Only then did debate become possible again; it was anchored in the nature-culture dichotomy such that groups switched from group-based to system-based emotions.

  6. Evolution in response to direct and indirect ecological effects in pitcher plant inquiline communities.

    PubMed

    terHorst, Casey P

    2010-12-01

    Ecologists have long recognized the importance of indirect ecological effects on species abundances, coexistence, and diversity. However, the evolutionary consequences of indirect interactions are rarely considered. Here I conduct selection experiments and examine the evolutionary response of Colpoda sp., a ciliated protozoan, to other members of the inquiline community of purple pitcher plants (Sarracenia purpurea). I measured the evolution of six traits in response to (1) predation by mosquito larvae, (2) competition from other ciliated protozoans, and (3) simultaneous predation and competition. The latter treatment incorporated both direct effects and indirect effects due to interactions between predators and competitors. Population growth rate and cell size evolved in response to direct effects of predators and competitors. However, trait values in the multispecies treatment were similar to those in the monoculture treatment, indicating that direct effects were offset by strong indirect effects on the evolution of traits. For most of the traits measured, indirect effects were opposed to, and often stronger than, direct effects. These indirect effects occurred as a result of behavioral changes of the predator in the presence of competitors and as a result of reduced densities of competitors in the presence of predators. Incorporating indirect effects provides a more realistic description of how species evolve in complex natural communities.

  7. Drivers and Dynamics of Ecological Responses to Abrupt Environmental Change on the Early Miocene Oregon Shelf

    NASA Astrophysics Data System (ADS)

    Belanger, C. L.

    2012-12-01

    We know that the biosphere responds to abrupt climate change, but know less about the dynamics of those changes and their proximal drivers. Studies of well-preserved fossil time-series spanning past climate events that utilize multiple environmental proxies and examine multiple taxonomic groups can provide critical insight into (a) the specific environmental factors to which the biota respond, (b) the rate and tempo of those responses, and (c) whether taxonomic groups respond similarly or differently to the same stresses. I examine the drivers and dynamics of ecological changes in continental shelf benthic foraminifera and molluscs from the Early Miocene Newport Member of the Astoria Formation in Oregon (20.3-16.3 mya), which spans a time of global warming leading into the Middle Miocene Climate Optimum. Stable isotope (δ18O) data from three species of benthic foraminifera from the Astoria sediments indicate that the region abruptly warmed by 2-4°C approximately 19 mya. In addition, δ13C values from epifaunal and infaunal foraminifera indicate an increase in productivity and organic carbon flux over time. Further, an increase in δ15N from bulk sediment and an increase in sedimentary laminations suggest oxygen levels declined. Multivariate analyses demonstrate a strong correlation between foraminiferal community metrics and δ15N suggesting that the foraminiferal community is tracking oxygenation levels while correlations to productivity changes appear indirect. Molluscan community metrics also have an approximately linear relationship to δ15N. Temperature itself had little direct influence on community composition. Changes in community composition and structure of both the foraminifera and the molluscs are abrupt relative to the duration of community states, but each group responds differently to the climate change. The foraminiferal community increases in the number of species and the evenness of species abundances while the molluscan community decreases in

  8. Modeling hydrologic and ecologic responses using a new eco-hydrological model for identification of droughts

    NASA Astrophysics Data System (ADS)

    Sawada, Yohei; Koike, Toshio; Jaranilla-Sanchez, Patricia Ann

    2014-07-01

    Drought severely damages water and agricultural resources, and both hydrological and ecological responses are important for its understanding. First, precipitation deficit induces soil moisture deficiency and high plant water stress causing agricultural droughts. Second, hydrological drought characterized by deficit of river discharge and groundwater follows agricultural drought. However, contributions of vegetation dynamics to these processes at basin scale have not been quantified. To address this issue, we develop an eco-hydrological model that can calculate river discharge, groundwater, energy flux, and vegetation dynamics as diagnostic variables at basin scale within a distributed hydrological modeling framework. The model is applied to drought analysis in the Medjerda River basin. From model inputs and outputs, we calculate drought indices for different drought types. The model shows reliable accuracy in reproducing observed river discharge in long-term (19 year) simulation. Moreover, the drought index calculated from the model-estimated annual peak of leaf area index correlates well (correlation coefficient r = 0.89) with the drought index from nationwide annual crop production, which demonstrates that the modeled leaf area index is capable of representing agricultural droughts related to historical food shortages. We show that vegetation dynamics have a more rapid response to meteorological droughts than river discharge and groundwater dynamics in the Medjerda basin because vegetation dynamics are sensitive to soil moisture in surface layers, whereas soil moisture in deeper layers strongly contributes to streamflow and groundwater level. Our modeling framework can contribute to analyze drought progress, although analyses for other climate conditions are needed.

  9. Response of aquatic invertebrates to ecological rehabilitation of Southeastern USA depressional wetlands.

    SciTech Connect

    Batzer, Donald P.; Taylor, Barbera E.

    2015-07-02

    Abstract We assessed aquatic invertebrate response to ecological rehabilitation treatment in 20 depression wetlands on the Savannah River Site, South Carolina, USA. All wetlands had been ditched for 50+ years. Sixteen of the 20 wetlands received rehabilitation treatment, and four wetlands remained untreated as a control group. Treatment included logging of all trees, plugging drainage ditches, and planting wetland trees and grasses. Hydroperiods were consequently extended in most of the treatment wetlands. As part a larger study, we sampled macroinvertebrates and microcrustaceans during the pre-habilitation (1998–2000) and rehabilitation (2001–2003) phases. Our study spanned 2 years of high rainfall (1998 and 2003) and 4 years of low rainfall (1999–2002). Samples were collected bimonthly from any wetlands holding water. Macroinvertebrate assemblages in treatment wetlands in 2003 had changed from previous years (1998–2002) and compared to control wetlands (1998–2003), with abundances of Baetidae, Coenagrionidae, Dytiscidae, Chironomidae, and Chaoboridae driving variation. For microcrustaceans (Copepoda and Branchiopoda, including Cladocera, Anostraca and Laevicaudata), assemblage composition and species richness responded mainly to hydrologic conditions. Rehabilitation efforts in these wetlands induced diverse and abundant invertebrate communities to develop, but some responses appeared opportunistic; several taxa that benefitted were not typical residents of depressional wetlands in the region.

  10. Thermal ecology of the fiddler crab Uca panacea: Thermal constraints and organismal responses.

    PubMed

    Darnell, M Zachary; Nicholson, Haley S; Munguia, Pablo

    2015-08-01

    Temperature is one of the primary environmental variables limiting organismal performance, fitness, and species distributions. Yet, understanding temperature effects requires thorough exploration of thermal constraints and organismal responses that can translate to fitness and non-lethal long-term consequences under both constant and changing thermal regimes. We examined the thermal ecology of the fiddler crab Uca panacea, including critical thermal limits, thermal sensitivity of locomotion, operative environmental temperatures, preferred body temperatures, and acclimation ability. Operative environmental temperatures frequently reached the critical thermal maximum (41.8±0.8°C, mean ± s.e.m.), especially in unvegetated microhabitats, indicating the need for behavioral thermoregulation to maintain diurnal activity patterns. Preferred body temperatures (21.1-28.6°C) were substantially below the thermal optimum (30-40°C), although further research is needed to determine the driver of this mismatch. Critical thermal limits shifted 2-4°C in response to exposure to low (20°C) or high (35°C) temperatures, with full acclimation occurring in approximately 9d. This capacity for rapid acclimation, combined with the capacity for behavioral thermoregulation, is a strong candidate mechanism that explains the broad habitat use and could help explain the successful pantropical distribution of fiddler crabs.

  11. Ecological Investigations of the Federally Endangered Shivwits Milk-Vetch (Astragalus ampullarioides)--2006 Annual Report

    USGS Publications Warehouse

    Miller, Mark E.; Mann, Rebecca K.; Goldstein, Harland L.; Yount, James D.

    2007-01-01

    Astragalus ampullarioides (Welsh) Welsh, the Shivwits milk-vetch, is an herbaceous perennial legume that was listed as federally endangered in September 2001. Known populations of this edaphic endemic species are restricted to Washington County, Utah, with the majority of occurrences found on gently sloping outcrops of the Triassic Petrified Forest Member of the Chinle Formation at the edge of the Mojave Desert. At the time of listing in 2001, surveys estimated a total of 1000 individuals for the species. In April-May 2006, surveys estimated approximately 4205 individuals distributed among six populations. Of the total number of individuals estimated in spring 2006, over 75 percent were distributed among three subpopulations in Zion National Park and approximately 60 percent occurred at a single 0.3-ha site in the Park. In addition to small population sizes and limited geographic distributions, the species is threatened to varying degrees by urbanization, livestock grazing, off-road vehicle use, and invasive exotic plants. In April 2006, the U.S. Geological Survey (USGS) initiated ecological investigations of the Shivwits milk-vetch to support conservation management and recovery of the species by the National Park Service (NPS; Zion National Park), the U.S. Fish and Wildlife Service (USFWS), the Bureau of Land Management (BLM), the Shivwits Band of the Paiute Tribe, and other cooperators such as The Nature Conservancy of Utah (TNC). To date, funding for this research has been provided by the Southwest Biological Science Center of the USGS Biological Resources Discipline, the USGS-NPS Park-Oriented Biological Support Project, and the Earth Surface Dynamics Program of the USGS Geologic Discipline. Additional logistical support has been provided by the Bureau of Land Management, Grand Staircase-Escalante National Monument. General objectives of this research are (1) to develop a better understanding of species-environment relations to support habitat modelling

  12. THE DEVELOPMENT OF EMPIRICAL LOAD-ECOLOGICAL RESPONSE MODELS TO DETERMINE NITROGEN LIMITS IN THE COASTAL ENVIRONMENT

    EPA Science Inventory

    The U.S. EPA Atlantic Ecology Division (AED) has initiated a multi-year research program to develop empirical nitrogen load-response models. Our research on embayments in southern New England is part of a multi-regional effort to develop cause-effect models for the Gulf of Mexic...

  13. Toward Resonant, Imaginative Experiences in Ecological and Democratic Education. A Response to "Imagination and Experience: An Integrative Framework"

    ERIC Educational Resources Information Center

    Derby, Michael; Blenkinsop, Sean; Telford, John; Piersol, Laura; Caulkins, Michael

    2013-01-01

    In this response to Fettes's "Imagination and Experience," the authors further consider the varieties of educational experience that inspire ecological flourishing and a living democracy. The essential interconnectedness of encounter-driven and language-driven ways of knowing are explored with particular reference to the…

  14. DOE responses to Ecology review comments for ``Sampling and analysis plans for the 100-D Ponds voluntary remediation project``

    SciTech Connect

    1996-12-31

    The Sampling and Analysis Plan describes the sampling and analytical activities which will be performed to support closure of the 100-D Ponds at the Hanford Reservation. This report contains responses by the US Department of Energy to Ecology review for ``Sampling and Analysis Plan for the 100-D Ponds Voluntary Remediation Project.``

  15. Ecological Stoichiometry and Density Responses of Plant-Arthropod Communities on Cormorant Nesting Islands

    PubMed Central

    Kolb, Gundula S.; Palmborg, Cecilia; Hambäck, Peter A.

    2013-01-01

    Seabirds deposit large amounts of nutrient rich guano on their nesting islands. The increased nutrient availability strongly affects plants and consumers. Consumer response differs among taxonomic groups, but mechanisms causing these differences are poorly understood. Ecological stoichiometry might provide tools to understand these mechanisms. ES suggests that nutrient rich taxa are more likely to be nutrient limited than nutrient poorer taxa and are more favored under nutrient enrichment. Here, we quantified differences in the elemental composition of soil, plants, and consumers between islands with and without nesting cormorant colonies and tested predictions made based on ES by relating the elemental composition and the eventual mismatch between consumer and resource stoichiometry to observed density differences among the island categories. We found that nesting cormorants radically changed the soil nutrient content and thereby indirectly plant nutrient content and resource quality to herbivores. In contrast, consumers showed only small differences in their elemental composition among the island categories. While we cannot evaluate the cause of the apparent homeostasis of invertebrates without additional data, we can conclude that from the perspective of the next trophic level, there is no difference in diet quality (in terms of N and P content) between island categories. Thus, bottom-up effects seemed mainly be mediated via changes in resource quantity not quality. Despite a large potential trophic mismatch we were unable to observe any relation between the invertebrate stoichiometry and their density response to nesting cormorant colonies. We conclude that in our system stoichiometry is not a useful predictor of arthropod responses to variation in resource nutrient content. Furthermore, we found no strong evidence that resource quality was a prime determinant of invertebrate densities. Other factors like resource quantity, habitat structure and species

  16. Ecological stoichiometry and density responses of plant-arthropod communities on cormorant nesting islands.

    PubMed

    Kolb, Gundula S; Palmborg, Cecilia; Hambäck, Peter A

    2013-01-01

    Seabirds deposit large amounts of nutrient rich guano on their nesting islands. The increased nutrient availability strongly affects plants and consumers. Consumer response differs among taxonomic groups, but mechanisms causing these differences are poorly understood. Ecological stoichiometry might provide tools to understand these mechanisms. ES suggests that nutrient rich taxa are more likely to be nutrient limited than nutrient poorer taxa and are more favored under nutrient enrichment. Here, we quantified differences in the elemental composition of soil, plants, and consumers between islands with and without nesting cormorant colonies and tested predictions made based on ES by relating the elemental composition and the eventual mismatch between consumer and resource stoichiometry to observed density differences among the island categories. We found that nesting cormorants radically changed the soil nutrient content and thereby indirectly plant nutrient content and resource quality to herbivores. In contrast, consumers showed only small differences in their elemental composition among the island categories. While we cannot evaluate the cause of the apparent homeostasis of invertebrates without additional data, we can conclude that from the perspective of the next trophic level, there is no difference in diet quality (in terms of N and P content) between island categories. Thus, bottom-up effects seemed mainly be mediated via changes in resource quantity not quality. Despite a large potential trophic mismatch we were unable to observe any relation between the invertebrate stoichiometry and their density response to nesting cormorant colonies. We conclude that in our system stoichiometry is not a useful predictor of arthropod responses to variation in resource nutrient content. Furthermore, we found no strong evidence that resource quality was a prime determinant of invertebrate densities. Other factors like resource quantity, habitat structure and species

  17. 32 CFR 536.22 - Claims investigative responsibility-General.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., evaluation, and settlement of tort and tort-related claims for and against the United States. The provisions... involving serious injury or death or those in which property damage exceeds $50,000. A command claims... 32 National Defense 3 2012-07-01 2009-07-01 true Claims investigative responsibility-General....

  18. 32 CFR 536.22 - Claims investigative responsibility-General.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., evaluation, and settlement of tort and tort-related claims for and against the United States. The provisions... involving serious injury or death or those in which property damage exceeds $50,000. A command claims... 32 National Defense 3 2014-07-01 2014-07-01 false Claims investigative responsibility-General....

  19. Ecological restoration and effect investigation of a river wetland in a semi-arid region, China

    NASA Astrophysics Data System (ADS)

    Xu, S.; Jiang, X.; Liu, Y.; Fu, Y.; Zhao, Q.

    2015-05-01

    River wetlands are heavily impacted by human intervention. The degradation and loss of river wetlands has made the restoration of river ecosystems a top priority. How to rehabilitate rivers and their services has been a research focus. The main goal of it is to restore the river wetland ecosystems with ecological methods. The Gudong River was selected as a study site in Chaoyang city in this study. Based on the analysis of interference factors in the river wetland degradation, a set of restoration techniques were proposed and designed for regional water level control, including submerged dikes, ecological embankments, revegetation and dredging. The restoration engineering has produced good results in water quality, eco-environment, and landscape. Monthly reports of the Daling River show that the water quality of Gudong River was better than Grade III in April 2013 compared with Grade V in May 2012. The economic benefit after restoration construction is 1.71 million RMB per year, about 1.89 times that before. The ratio of economic value, social value and eco-environmental value is 1:4:23.

  20. Investigation of ecological parameters of four-stroke SI engine, with pneumatic fuel injection system

    NASA Astrophysics Data System (ADS)

    Marek, W.; Śliwiński, K.

    2016-09-01

    The publication presents the results of tests to determine the impact of using waste fuels, alcohol, to power the engine, on the ecological parameters of the combustion engine. Alternatively fuelled with a mixture of iso- and n-butanol, indicated with "X" and "END, and gasoline and a mixture of fuel and alcohol. The object of the study was a four-stroke engine with spark ignition designed to work with a generator. Motor power was held by the modified system of pneumatic injection using hot exhaust gases developed by Prof. Stanislaw Jarnuszkiewicz, controlled by modern mechatronic systems. Tests were conducted at a constant speed for the intended use of the engine. The subject of the research was to determine the control parameters such as ignition timing, mixture composition and the degree of exhaust gas recirculation on the ecological parameters of the engine. Tests were carried out using partially quality power control. In summary we present the findings of this phase of the study.

  1. Spatial economy and integrative labor in Turkey: an ecological, modernization, and world-system investigation.

    PubMed

    Clarke, C J; Shyu, L

    1991-08-01

    Studies testing theories of urban primacy and foreign penetration in developing nations largely support the premise that these phenomena both prevail and negatively impact economic growth in developing nations. This paper, however, presents results of a study of Turkey as an exception to patterns reflective of the world-system model and dependency theory found in ideal-typic developing nations. Theoretically, 1 or 2 major urban centers may distort and fragment the spatial economy of a developing nation. These cities are able to politically and economically manipulate/regulate national policy in their self-interest, and leave nonprimate regions as fragmented local markets. As such, these cities impede the development of an integrated spatial economy. From the birth of the Turkish nation-state in 1923, however, a strong central government has structured economic and political patterns to direct national control away from Istanbul-centric interest groups. Moreover, little support exists for the presence of foreign economic domination. The paper then examines to what extent the Turkish spatial economy has become less distorted and fragmented. It subjects 1955-80 data to modernization theory and human ecology, and finds no support for ecological arguments linking integrative activity to system size or contact technology. Study results confirm the modernization argument about spatial economy, with more modernized provinces showing proportionately higher levels of integrative activity. Finding implications are briefly discussed.

  2. Estimating hydrologic and erosion response for use in ecological site descriptions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ecological resilience of rangeland landscapes is strongly related to eco-hydrologic pattern-process feedbacks that regulate the retention or loss of water and soil resources. However, key ecohydrologic information is often lacking in Ecological Site Descriptions (ESDs) used to guide management of ra...

  3. A Combined Ecological and Epidemiologic Investigation of Metals Exposure amongst Indigenous Peoples Near the Marlin Mine in Western Guatemala

    PubMed Central

    Basu, Niladri; Abare, Marce; Buchanan, Susan; Cryderman, Diana; Nam, Dong-Ha; Sirkin, Susannah; Schmitt, Stefan; Hu, Howard

    2016-01-01

    In August 2009 a combined epidemiological and ecological pilot study was conducted to investigate allegations of human rights abuses in the form of exposures to toxic metals experienced by mine workers and Indigenous Mam Mayan near the Marlin Mine in Guatemala. In the human study there were no differences in blood and urine metals when comparing five mine workers with eighteen non-mine workers, and there were no discernible relationships between metals exposures and self-reported health measures in any study group. On the other hand, individuals residing closest to the mine had significantly higher levels of certain metals (urinary mercury, copper, arsenic, zinc) when compared to those living further away. Levels of blood aluminum, manganese, and cobalt were elevated in comparison to established normal ranges in many individuals; however, there was no apparent relationship to proximity to the mine or occupation, and thus are of unclear significance. In the ecological study, several metals (aluminum, manganese, cobalt) were found significantly elevated in the river water and sediment sites directly below the mine when compared to sites elsewhere. When the results of the human and ecological results are combined, they suggest that exposures to certain metals may be elevated in sites near the mine but it is not clear if the current magnitude of these elevations poses a significant threat to health. The authors conclude that more robust studies are needed while parallel efforts to minimize the ecological and human impacts of mining proceed. This is critical particularly as the impact of the exposures found could be greatly magnified by expected increases in mining activity over time, synergistic toxicity between metals, and susceptibility for the young and those with pre-existing disease. PMID:20952048

  4. Coarse-scale spatial and ecological analysis of tuberculosis in cattle: an investigation in Jalisco, Mexico.

    PubMed

    Zendejas-Martínez, Horacio; Townsend Peterson, A; Milián-Suazo, Feliciano

    2008-11-01

    We have tested the hypothesis that coarse-scale environmental features are associated with spatial variation in bovine tuberculosis (BTB) prevalence, based on extensive sampling and testing of cattle in the state of Jalisco, Mexico. Ecological niche models were developed to summarize relationships between BTB occurrences and aspects of climate, topography and surface. Model predictions, however, reflected the distributions of dairy cattle versus beef cattle, and the non-random nature of sampling any cattle, but did not succeed in detecting environmental correlates at spatial resolutions of 1 km. Given that the tests employed seek any predictivity better than random expectations, making the finding of no environmental associations conservative, we conclude that BTB prevalence is independent of coarsescale environmental features.

  5. Effects of pyrite sludge pollution on soil enzyme activities: ecological dose-response model.

    PubMed

    Hinojosa, M Belén; Carreira, José A; Rodríguez-Maroto, José M; García-Ruíz, Roberto

    2008-06-25

    A laboratory study was conducted to evaluate the response of soil enzyme activities (acid and alkaline phosphatase, beta-glucosidase, arylsulfatase, urease and dehydrogenase) to different levels of trace elements pollution in soils representative of the area affected by the pyrite sludge mining spill of Aznalcóllar (Guadiamar basin, SW Spain). Three uncontaminated soils from the study area were mixed with different loads of pyrite sludge to resemble field conditions and criteria applied for reclamation practices following the pollution incident: 0% ("reference" or background level), 1.3% ("attention level", further monitoring required), 4% ("intervention level", further cleaning and liming required) and 13% (ten times the "attention level"). Enzyme activities were analysed 4, 7, 14, 21, 34 and 92 days after pollutant addition and those measured after 92 days were used to calculate the ecological dose value (ED50). Soil enzyme activities and pH decreased after the pyrite sludge addition with respect to the "reference level" (0% pyrite sludge), whereas soil bioavailable (DTPA-extractable) trace elements concentration increased. Arylsulfatase, beta-glucosidase and phosphatase activities were reduced by more than 50% at 1.3% pyrite sludge dose. Arylsulfasate was the most sensitive soil enzyme (in average, ED50=0.99), whereas urease activity showed the lowest inhibition (in average, ED50=7.87) after pyrite sludge addition. Our results showed that the ecological dose concept, applied to enzyme activities, was satisfactory to quantify the effect of a multi-metalic pollutant (pyrite sludge) on soil functionality, and would provide manageable data to establish permissible limits of trace elements in polluted soils. Additionally, we evaluate the recovery of enzyme activities after addition of sugar-beet lime (calcium carbonate) to each experimentally polluted soil. The amount of lime added to each soil was enough to raise the pH to the original value (equal to control soil

  6. An Experimental Investigation of Reactivity to Ecological Momentary Assessment Frequency among Adults Trying to Quit Smoking

    PubMed Central

    Minami, Haruka; Yeh, Vivian M.; Bold, Krysten W.

    2015-01-01

    Aims Ecological Momentary Assessment (EMA) captures real-time reports in subjects’ natural environments. This experiment manipulated EMA frequency to estimate effects on abstinence and peri-cessation subjective experiences. Design In this randomized trial, subjects had an equal chance of being assigned to low-frequency (once) or high-frequency (6 times) daily EMA for 4 weeks (1 week pre- and 3 weeks post-cessation). Participants completed 6 office visits over 5 weeks and 6- and 12-week follow-up telephone interviews. Setting Community participants were recruited from central New Jersey, USA. Participants 110 adult daily smokers seeking to quit smoking were included in intent-to-treat analyses of tobacco abstinence; 94 were available for secondary analyses of peri-cessation subjective ratings. Measurements Primary outcomes were cessation (abstaining at least 24 hours within 2 weeks of attempting to quit) and prolonged abstinence (no relapse between weeks 2 and 12 post-quit). Secondary outcomes were mean levels and growth in ratings of cigarette craving, affect, and quitting motivation and self-efficacy. Findings EMA frequency was unrelated to cessation (Odds Ratio=1.37, 95% CI=0.60–3.10) or prolonged abstinence (Odds Ratio=1.04, 95% CI=0.45–2.39) in intent-to-treat analyses. High-frequency EMA was associated with lower craving (B=−.54, SE=.18, p=.004, anxiety (B=−.42, SE=.17, p=.015), anger (B=−.47, SE=.14, p=.001), hunger (B=−.39, SE=.17, p=0.25), and positive affect (B=−.43, SE=.20, p=.03). Conclusions In smokers trying to quit, more frequent ecological momentary assessment (EMA) self-monitoring results in lower craving, anxiety, anger, hunger, and positive affect. It is not clear whether this translates into higher rates of smoking abstinence. PMID:26011583

  7. Mesoscale disturbance and ecological response to decadal climatic variability in the American Southwest

    USGS Publications Warehouse

    Swetnam, T.W.; Betancourt, J.L.

    1998-01-01

    Ecological responses to climatic variability in the Southwest include regionally synchronized fires, insect outbreaks, and pulses in tree demography (births and deaths). Multicentury, tree-ring reconstructions of drought, disturbance history, and tree demography reveal climatic effects across scales, from annual to decadal, and from local (<102 km2) to mesoscale (104-106 km2). Climate-disturbance relations are more variable and complex than previously assumed. During the past three centuries, mesoscale outbreaks of the western spruce budworm (Choristoneura occidentalis) were associated with wet, not dry episodes, contrary to conventional wisdom. Regional fires occur during extreme droughts but, in some ecosystems, antecedent wet conditions play a secondary role by regulating accumulation of fuels. Interdecadal changes in fire-climate associations parallel other evidence for shifts in the frequency or amplitude of the Southern Oscillation (SO) during the past three centuries. High interannual, fire-climate correlations (r = 0.7 to 0.9) during specific decades (i.e., circa 1740-80 and 1830-60) reflect periods of high amplitude in the SO and rapid switching from extreme wet to dry years in the Southwest, thereby entraining fire occurrence across the region. Weak correlations from 1780 to 1830 correspond with a decrease in SO frequency or amplitude inferred from independent tree-ring width, ice core, and coral isotope reconstructions. Episodic dry and wet episodes have altered age structures and species composition of woodland and conifer forests. The scarcity of old, living conifers established before circa 1600 suggests that the extreme drought of 1575-95 had pervasive effects on tree populations. The most extreme drought of the past 400 years occurred in the mid-twentieth century (1942-57). This drought resulted in broadscale plant dieoffs in shrublands, woodlands, and forests and accelerated shrub invasion of grasslands. Drought conditions were broken by the post

  8. Response of peatland ecosystem to climatic changes in Central-Eastern Europe: a long-term ecological approach

    NASA Astrophysics Data System (ADS)

    Slowinska, S.; Marcisz, K.; Slowinski, M. M.; Lamentowicz, M.; Lamentowicz, L.; Mitchell, E. A.

    2013-12-01

    Northern peatlands play a major role in the global carbon cycle, and they are valuable archives of the past environmental change. The functioning of these ecosystems depends on the feedback between biotic and abiotic factors that are still not fully understood. In our study we investigated relationships between hydrological (groundwater level fluctuations, hydrochemistry), meteorological conditions near the ground (air temperature and humidity, photosynthetically active radiation, leaf wetness, temperature and moisture of Sphagnum) and biological factors: vegetation patterns, Sphagnum mosses growth and testate amoebae (Protists) composition. We designed a long-term ecological study site in a Sphagnum mire in Northern Poland that consisted of five meteorological micro stations and eleven piezometers located in two transects at 5,95 ha area. During the growing season 2012 we observed significant differences between plots in terms of micrometeorological and hydrological conditions that resulted in different Sphagnum increments and seasonal dynamics of testate amoebae communities. Our study is very important to better understand how temperate peatlands react to the climatic change and recent warming. Obtained results revealed a high sensitivity of bog ecosystem to e.g. short-term heat waves. Further research will be conducted to model a potential response of Sphagnum peatland to the future climate change. Project supported by Polish National Science Centre grant No. NN306060940 and the grant PSPB-013/2010 from Switzerland through the Swiss Contribution to the enlarged European Union.

  9. Do Young and Old Preschoolers Exhibit Response Bias Due to Different Mechanisms? Investigating Children's Response Time

    ERIC Educational Resources Information Center

    Okanda, Mako; Itakura, Shoji

    2011-01-01

    Previous studies have suggested that younger preschoolers exhibit a yes bias due to underdeveloped cognitive abilities, whereas older preschoolers exhibit a response bias due to other factors. To test this hypothesis, we investigated the response latency to yes-no questions pertaining to familiar and unfamiliar objects in 3- to 6-year-olds. The…

  10. Seasonally chemical hydrology and ecological responses in frontal zone of the central southern Yellow Sea

    NASA Astrophysics Data System (ADS)

    Wei, Qin-Sheng; Li, Xian-Sen; Wang, Bao-Dong; Fu, Ming-Zhu; Ge, Ren-Feng; Yu, Zhi-Gang

    2016-06-01

    Based on annual-cycle survey data collected in 2006-2007 in the southern Yellow Sea (SYS) and analyses on the seasonally chemical hydrologic characteristics of the boundary front of the Yellow Sea Cold Water Mass (YSCWM) and Yellow Sea Warm Current (YSWC), the seasonal variations in upwelling along the frontal zone were determined, and the ecological impacts of the front were investigated. During the generation and dissipation of the YSCWM, the implied upwelling along its western front exhibited seasonal variation. The upwelling first shifted westward from the deep-water region to its westernmost point in summer then returned eastward. The intensity of the upwelling gradually increased from spring to summer and decreased in autumn. In spring, the existence of cold water west of the YSWC was not conducive to the reproduction of phytoplankton. Additionally, the front to the east of this cold water mass also made the western boundary of the phytoplankton bloom region in the central SYS more obvious, forming a prominent chlorophyll a (Chl-a) front. During the entire stratified season (summer and autumn), the upwelling in the frontal zone of the YSCWM played an essential role in maintaining the relatively high concentrations of Chl-a. In winter, the front that formed at the intersection of the YSWC and coastal cold water was also favorable for the formation of the high-Chl-a region. The distribution of anchovy biomass was closely related to the seasonal variations in the position of the frontal zone. In winter and spring, the tongue-shaped warm water and front associated with the intrusion of the YSWC into the SYS had a significant impact on anchovy. During the stratified season in summer and autumn, the development of a front near the boundary of the YSCWM was an important physical driving mechanism for the dense distribution of anchovy. This work enhanced the study of the seasonal relationships between the physical, chemical and biological processes in the frontal

  11. Critical Aspects of the Coastal Drought Index: Length of Salinity Data Record and Ecological Response Data

    NASA Astrophysics Data System (ADS)

    Conrads, P. A.; Tufford, D. L.; Darby, L. S.

    2015-12-01

    The phenomenon of coastal drought has a different dynamic from upland droughts that are typically characterized by agricultural, hydrologic, meteorological, and(or) socio-economic impacts. Because of the uniqueness of drought impacts on coastal ecosystems, a coastal drought index (CDI) that uses existing salinity datasets for sites in South Carolina, Georgia, and Florida was developed using an approach similar to the Standardized Precipitation Index (SPI). CDIs characterizing the 1- to 24-month salinity conditions were developed and the evaluation of the CDI indicates that the index can be used for different estuary types (for example, brackish, olioghaline, or mesohaline), for regional comparison between estuaries, and as an index for wet conditions (high freshwater inflow) in addition to drought conditions. Unlike the SPI where long-term precipitation datasets of 50 to 100 years are available for computing the index, there are a limited number of salinity data sets of greater than 10 or 15 years for computing the CDI. To evaluate the length of salinity record necessary to compute the CDI, a 29-year dataset was resampled into 5-, 10-, 15-, and 20-year interval datasets. Comparison of the CDI for the different periods of record show that the range of salinity conditions in the 10-, 15-, and 20-year datasets were similar and results were a close approximation to the CDI computed by using the full period of record. The CDI computed with the 5-year dataset had the largest differences with the CDI computed with the 29-year dataset but did provide useful information on coastal drought and freshwater conditions. An ongoing National Integrated Drought Information System (NIDIS) drought early warning project in the Carolinas is developing ecological linkages to the CDI and evaluating the effectiveness of the CDI as a prediction tool for adaptation planning for future droughts. However, identifying potential coastal drought response datasets is a challenge. Coastal drought

  12. An Overview of Stream Ecological Responses to Urban Effects and Management Practices in New England

    EPA Science Inventory

    Many recent studies have found large changes in ecological conditions related to small increases in watershed development. Future development and restoration practices will benefit from better documenting the effectiveness of management practices. We present (1) a brief summary o...

  13. Novel study designs to investigate the placebo response

    PubMed Central

    2011-01-01

    Background Investigating the size and mechanisms of the placebo response in clinical trials have relied on experimental procedures that simulate the double-blind randomized placebo-controlled design. However, as the conventional design is thought to elucidate drug rather than placebo actions, different methodological procedures are needed for the placebo response. Methods We reviewed the respective literature for trials designs that may be used to elucidate the size of the placebo response and the mechanisms associated with it. Results In general, this can be done by either manipulation the information provided to the subjects, or by manipulation the timing of the drug applied. Two examples of each strategy are discussed: the "balanced placebo design" (BDP) and the "balanced cross-over design" (BCD) and their variants are based on false information, while the "hidden treatment" (HT) and the ""delayed response test" (DRT) are based on manipulating the time of drug action. Since most such approaches include deception or incomplete information of the subjects they are suitable for patient only with authorized deception. Conclusion Both manipulating the information provided to subjects (BDP, DCD) or manipulating the timing of drug application (HT, DRT) allows overcoming some of the restrictions of conventional drug trials in the assessment of the placebo response, but they are feasible mostly in healthy subjects for ethical reasons. PMID:21663609

  14. WAG 2 remedial investigation and site investigation site-specific work plan/health and safety checklist for the ecological assessment task, Kingfisher Study

    SciTech Connect

    Holt, V.L.; Baron, L.A.

    1994-05-01

    This report provides specific details and requirements for the WAG 2 remedial investigation and site investigation Ecological Assessment Task, Kingfisher Study, including information that will contribute to safe completion of the project. The report includes historical background; a site map; project organization; task descriptions and hazard evaluations; controls; and monitoring, personal protective equipment, decontamination, and medical surveillance program requirements. The report also includes descriptions of site personnel and their certifications as well as suspected WAG 2 contaminants and their characteristics. The primary objective of the WAG 2 Kingfisher Study is to assess the feasibility of using kingfishers as biological monitors of contaminants on the Oak Ridge Reservation (ORR). Kingfisher sample collection will be used to determine the levels of contaminants and degree of bioaccumulation within a common piscivorous bird feeding on contaminated fish from streams on the ORR.

  15. Mesoscale Disturbance and Ecological Response to Decadal Climatic Variability in the American Southwest.

    NASA Astrophysics Data System (ADS)

    Swetnam, Thomas W.; Betancourt, Julio L.

    1998-12-01

    Ecological responses to climatic variability in the Southwest include regionally synchronized fires, insect outbreaks, and pulses in tree demography (births and deaths). Multicentury, tree-ring reconstructions of drought, disturbance history, and tree demography reveal climatic effects across scales, from annual to decadal, and from local (<102 km2) to mesoscale (104-106 km2). Climate-disturbance relations are more variable and complex than previously assumed. During the past three centuries, mesoscale outbreaks of the western spruce budworm (Choristoneura occidentalis) were associated with wet, not dry episodes, contrary to conventional wisdom. Regional fires occur during extreme droughts but, in some ecosystems, antecedent wet conditions play a secondary role by regulating accumulation of fuels. Interdecadal changes in fire-climate associations parallel other evidence for shifts in the frequency or amplitude of the Southern Oscillation (SO) during the past three centuries. High interannual, fire-climate correlations (r = 0.7 to 0.9) during specific decades (i.e., circa 1740-80 and 1830-60) reflect periods of high amplitude in the SO and rapid switching from extreme wet to dry years in the Southwest, thereby entraining fire occurrence across the region. Weak correlations from 1780 to 1830 correspond with a decrease in SO frequency or amplitude inferred from independent tree-ring width, ice core, and coral isotope reconstructions.Episodic dry and wet episodes have altered age structures and species composition of woodland and conifer forests. The scarcity of old, living conifers established before circa 1600 suggests that the extreme drought of 1575-95 had pervasive effects on tree populations. The most extreme drought of the past 400 years occurred in the mid-twentieth century (1942-57). This drought resulted in broadscale plant dieoffs in shrublands, woodlands, and forests and accelerated shrub invasion of grasslands. Drought conditions were broken by the post

  16. Studying global change through investigation of the plastic responses of xylem anatomy in tree rings.

    PubMed

    Fonti, Patrick; von Arx, Georg; García-González, Ignacio; Eilmann, Britta; Sass-Klaassen, Ute; Gärtner, Holger; Eckstein, Dieter

    2010-01-01

    Variability in xylem anatomy is of interest to plant scientists because of the role water transport plays in plant performance and survival. Insights into plant adjustments to changing environmental conditions have mainly been obtained through structural and functional comparative studies between taxa or within taxa on contrasting sites or along environmental gradients. Yet, a gap exists regarding the study of hydraulic adjustments in response to environmental changes over the lifetimes of plants. In trees, dated tree-ring series are often exploited to reconstruct dynamics in ecological conditions, and recent work in which wood-anatomical variables have been used in dendrochronology has produced promising results. Environmental signals identified in water-conducting cells carry novel information reflecting changes in regional conditions and are mostly related to short, sub-annual intervals. Although the idea of investigating environmental signals through wood anatomical time series goes back to the 1960s, it is only recently that low-cost computerized image-analysis systems have enabled increased scientific output in this field. We believe that the study of tree-ring anatomy is emerging as a promising approach in tree biology and climate change research, particularly if complemented by physiological and ecological studies. This contribution presents the rationale, the potential, and the methodological challenges of this innovative approach.

  17. Studying global change through investigation of the plastic responses of xylem anatomy in tree rings.

    PubMed

    Fonti, Patrick; von Arx, Georg; García-González, Ignacio; Eilmann, Britta; Sass-Klaassen, Ute; Gärtner, Holger; Eckstein, Dieter

    2010-01-01

    Variability in xylem anatomy is of interest to plant scientists because of the role water transport plays in plant performance and survival. Insights into plant adjustments to changing environmental conditions have mainly been obtained through structural and functional comparative studies between taxa or within taxa on contrasting sites or along environmental gradients. Yet, a gap exists regarding the study of hydraulic adjustments in response to environmental changes over the lifetimes of plants. In trees, dated tree-ring series are often exploited to reconstruct dynamics in ecological conditions, and recent work in which wood-anatomical variables have been used in dendrochronology has produced promising results. Environmental signals identified in water-conducting cells carry novel information reflecting changes in regional conditions and are mostly related to short, sub-annual intervals. Although the idea of investigating environmental signals through wood anatomical time series goes back to the 1960s, it is only recently that low-cost computerized image-analysis systems have enabled increased scientific output in this field. We believe that the study of tree-ring anatomy is emerging as a promising approach in tree biology and climate change research, particularly if complemented by physiological and ecological studies. This contribution presents the rationale, the potential, and the methodological challenges of this innovative approach. PMID:19780986

  18. Educational and Ecological Correlates of IQ: A Cross-National Investigation

    ERIC Educational Resources Information Center

    Barber, N.

    2005-01-01

    The new paradigm of evolutionary social science suggests that humans adjust rapidly to changing economic conditions, including cognitive changes in response to the economic significance of education. This research tested the predictions that cross-national differences in IQ scores would be positively correlated with education and negatively…

  19. Preliminary investigations of the winter ecology of Long-billed Curlews in coastal Texas

    USGS Publications Warehouse

    Woodin, Marc C.; Skoruppa, Mary Kay; Edwardson, Jeremy W.; Austin, Jane E.

    2012-01-01

    Results from this 1-year pilot study yielded an intriguing combination of findings that warrant further investigation. Observations include reduced numbers of roosting birds along the Texas coast during dry conditions, highly dynamic use of nocturnal roost sites, use of widely divergent habitat types for foraging, low body mass of most captured birds, and apparent fidelity to general feeding areas. Future investigations of this eastern winter population of curlews would benefit from larger sample sizes and monitoring of individual birds.

  20. Connecting Urban Youth with their Environment: The Impact of an Urban Ecology Course on Student Content Knowledge, Environmental Attitudes and Responsible Behaviors

    NASA Astrophysics Data System (ADS)

    Hashimoto-Martell, Erin A.; McNeill, Katherine L.; Hoffman, Emily M.

    2012-10-01

    This study explores the impact of an urban ecology program on participating middle school students' understanding of science and pro-environmental attitudes and behaviors. We gathered pre and post survey data from four classes and found significant gains in scientific knowledge, but no significant changes in student beliefs regarding the environment. We interviewed 12 students to better understand their beliefs. Although student responses showed they had learned discrete content knowledge, they lacked any ecological understanding of the environment and had mixed perceptions of the course's relevance in their lives. Students reported doing pro-environmental behaviors, but overwhelmingly contributed such actions to influences other than the urban ecology course. Analyses indicated a disconnect between the course, the environment, and the impact on the students' lives. Consequently, this suggests the importance of recognizing the implications of context, culture, and identity development of urban youth. Perhaps by providing explicit connections and skills in urban environmental programs through engaging students in environmental scientific investigations that stem from their own issues and questions can increase student engagement, motivation, and self-efficacy of environmental issues.

  1. Response of phytoplankton and dissolved oxygen and related marine ecological parameters to typhoon tropical cyclone in the oceans

    NASA Astrophysics Data System (ADS)

    Tang, DanLing

    Typhoons (tropical cyclones, or hurricanes) are strong wind events in the weather system, which influence the upper ocean dynamics and the ecosystem, in particular upwelling, water temperature, salinity, chlorophyll-a (Chl-a) concentration and primary production and fish abundances. But little is known about the response of dissolved oxygen (DO) concentration to a typhoon in the open ocean. This paper investigates the impact of a typhoon on DO concentration and related ecological parameters using in-situ and remote sensing data. The in-situ data were collected one week after the passage of the super-typhoon Nanmadol in the northern South China Sea in 2011. An increase in DO concentration, accompanied by a decrease in water temperature and an increase in salinity and Chl-a concentration, was measured at sampling stations close to the typhoon track. At these stations, maximum DO concentration was found at a depth of around 5 m and maximum Chl-a concentration at depths between 50 m and 75 m. The layer of high DO concentration extends from the surface to a depth of 35 m and the concentrations stay almost constant down to this depth. Due to the passage of the typhoon, also a large sea level anomaly (21.6 cm) and a high value of Ekman pumping velocity (4.0×10-4 m s-1) are observed, indicating upwelling phenomenon. At the same time, also intrusion of Kuroshio waters in the form of a loop current into the South China Sea (SCS) was observed. We attribute the increase of DO concentration after the passage of the typhoon to three effects:1) entrainment of oxygen from the air into the upper water layer and strong vertical mixing of the water body due to the typhoon winds, 2) upwelling of cold nutrient-rich water which stimulates photosynthesis of phytoplankton and thus the generation of oxygen, which also increases the DO concentration due to cold water since the solubility of oxygen increase with decreasing water temperature, and, possibly, 3) transport of DO enriched waters

  2. Considerations of Scale and Processes in Stream Restoration and Ecological Response

    NASA Astrophysics Data System (ADS)

    Simon, A.; Shields, D.; Kuhnle, R.; Knight, S.

    2005-12-01

    Stream restoration as a means of controlling accelerated channel erosion and improving biological function in streams has become pervasive in the United States over the past twenty years. A broad range of practices often involving direct modifications to stream channels and adjacent floodplains, including alterations to morphology and pattern have been used for stream restoration. Because alluvial-channel processes and biological functioning operate as linked, open systems, any restoration project must be placed in the context of existing watershed and channel processes with a quantitative understanding of the rates of transfer of flow energy and materials. This is particularly true of reach-scale projects where local stabilization and habitat improvements may be completely overwhelmed by watershed or channel-system scale instabilities. In this regard, it is unlikely that a reach-scale project will be successful in an unstable alluvial system. This is analogous to constructing bank-stabilization measures in an actively incising channel. A conceptual model of channel response and evolution that marks systematic shifts in channel processes over time and space has been linked to fish-community structure in Mississippi streams. This link reflects changing habitat conditions and sediment-transport regimes over the course of fluvial adjustment. Suspended-sediment concentrations that can increase by orders of magnitude for a given discharge during the incision and mass-wasting phases abrade fish gills and reduce the ability of fish to hunt for food due to reduced water clarity. Similarly, durations of high suspended-sediment concentrations are shown to be inversely related to numbers of benthic macro invertebrates. Streambeds experiencing active incision (Stage III) may be too mobile for benthic macro invertebrate communities to thrive. Channels dominated by mass-wasting processes (Stages IV and V) lose riparian vegetative cover and shading which may result in higher

  3. A review of fire effects on vegetation and soils in the Great Basin region: response and ecological site characteristics

    USGS Publications Warehouse

    Miller, Richard F.; Chambers, Jeanne C.; Pyke, David A.; Pierson, Fred B.; Williams, C. Jason

    2013-01-01

    This review synthesizes the state of knowledge on fire effects on vegetation and soils in semi-arid ecosystems in the Great Basin Region, including the central and northern Great Basin and Range, Columbia River Basin, and the Snake River Plain. We summarize available literature related to: (1) the effects of environmental gradients, ecological site, and vegetation characteristics on resilience to disturbance and resistance to invasive species; (2) the effects of fire on individual plant species and communities, biological soil crusts, seed banks, soil nutrients, and hydrology; and (3) the role of fire severity, fire versus fire surrogate treatments, and post-fire grazing in determining ecosystem response. From this, we identify knowledge gaps and present a framework for predicting plant successional trajectories following wild and prescribed fires and fire surrogate treatments. Possibly the three most important ecological site characteristics that influence a site’s resilience (ability of the ecological site to recover from disturbance) and resistance to invasive species are soil temperature/moisture regimes and the composition and structure of vegetation on the ecological site just prior to the disturbance event.

  4. Animal behaviour shapes the ecological effects of ocean acidification and warming: moving from individual to community-level responses.

    PubMed

    Nagelkerken, Ivan; Munday, Philip L

    2016-03-01

    Biological communities are shaped by complex interactions between organisms and their environment as well as interactions with other species. Humans are rapidly changing the marine environment through increasing greenhouse gas emissions, resulting in ocean warming and acidification. The first response by animals to environmental change is predominantly through modification of their behaviour, which in turn affects species interactions and ecological processes. Yet, many climate change studies ignore animal behaviour. Furthermore, our current knowledge of how global change alters animal behaviour is mostly restricted to single species, life phases and stressors, leading to an incomplete view of how coinciding climate stressors can affect the ecological interactions that structure biological communities. Here, we first review studies on the effects of warming and acidification on the behaviour of marine animals. We demonstrate how pervasive the effects of global change are on a wide range of critical behaviours that determine the persistence of species and their success in ecological communities. We then evaluate several approaches to studying the ecological effects of warming and acidification, and identify knowledge gaps that need to be filled, to better understand how global change will affect marine populations and communities through altered animal behaviours. Our review provides a synthesis of the far-reaching consequences that behavioural changes could have for marine ecosystems in a rapidly changing environment. Without considering the pervasive effects of climate change on animal behaviour we will limit our ability to forecast the impacts of ocean change and provide insights that can aid management strategies. PMID:26700211

  5. Animal behaviour shapes the ecological effects of ocean acidification and warming: moving from individual to community-level responses.

    PubMed

    Nagelkerken, Ivan; Munday, Philip L

    2016-03-01

    Biological communities are shaped by complex interactions between organisms and their environment as well as interactions with other species. Humans are rapidly changing the marine environment through increasing greenhouse gas emissions, resulting in ocean warming and acidification. The first response by animals to environmental change is predominantly through modification of their behaviour, which in turn affects species interactions and ecological processes. Yet, many climate change studies ignore animal behaviour. Furthermore, our current knowledge of how global change alters animal behaviour is mostly restricted to single species, life phases and stressors, leading to an incomplete view of how coinciding climate stressors can affect the ecological interactions that structure biological communities. Here, we first review studies on the effects of warming and acidification on the behaviour of marine animals. We demonstrate how pervasive the effects of global change are on a wide range of critical behaviours that determine the persistence of species and their success in ecological communities. We then evaluate several approaches to studying the ecological effects of warming and acidification, and identify knowledge gaps that need to be filled, to better understand how global change will affect marine populations and communities through altered animal behaviours. Our review provides a synthesis of the far-reaching consequences that behavioural changes could have for marine ecosystems in a rapidly changing environment. Without considering the pervasive effects of climate change on animal behaviour we will limit our ability to forecast the impacts of ocean change and provide insights that can aid management strategies.

  6. Behaviour of mobile macrofauna is a key factor in beach ecology as response to rapid environmental changes

    NASA Astrophysics Data System (ADS)

    Scapini, Felicita

    2014-10-01

    Sandy beach animals show behavioural adaptations that are expressed as contingencies during the life history of individuals to face periodic and episodic environmental changes. Such adaptations include activity rhythms, orientation, zonation, burrowing, escape responses and feeding strategies, the first two being common adaptations to all mobile animals. The complex conditions of a particular beach environment may be integrated in a learning process enhancing the adaptation and survival of individuals and eventually of populations. Evidence exists of genetic determination of some behavioural features that are adaptive in the long term (throughout generations) by increasing individual survival and reproductive potential. The environmental features integrated with the life history of beach animals shape the individual behaviour through ontogenetic processes, as well as population behaviour through evolutionary processes. Thus, behavioural differences among individuals may reflect environmental variation at the local and small/medium temporal scales of beach processes, whereas within-population behavioural coherence and differences among populations may reflect variation at the geographic scale. The different foci stressed by different authors and the variety of evidence dependent upon local geographical and ecological conditions have often resulted in compartmentalised explanations, making generalizations and the repeatability of behavioural studies of beach ecology challenging. There was a need to developing a more synthetic paradigm for beach animal behaviour. This paper gives a brief overview of the theoretical background and keystone studies, which have contributed to our understanding of animal behaviour in sandy beach ecology, and proposes testable hypotheses to be integrated in the beach ecology paradigm.

  7. A social ecological approach to investigating relationships between housing and adaptive functioning for persons with serious mental illness.

    PubMed

    Kloos, Bret; Shah, Seema

    2009-12-01

    This paper seeks to advance mental health-housing research regarding which factors of housing and neighborhood environments are critical for adaptive functioning, health, and recovery for persons with serious mental illness (SMI). Housing and neighborhood environments are particularly important for persons with SMI because of the prevalence of poor housing conditions among this population. Most mental health-housing research has been limited by a focus on problems in environments and functioning. The paper seeks to expand the mental health-housing research agenda to consider protective factors that promote community integration and adaptive functioning. We provide an account of how social ecology theory transformed a research program, from examining individual risk factors to investigating the functioning of persons in the contexts of their housing and neighborhood experiences. The resulting housing environment framework-physical aspects of housing and neighborhoods, social environment of neighborhoods, and interpersonal relationships tied to housing-allows for identification of opportunities for health promotion and facilitation of participation in community-based settings. This program of research draws upon several methods to understand the social experience of persons with SMI living in community settings-survey research, qualitative interviews, Geographic Information Systems, participatory research, and visual ethnography. In this paper, we present how social ecology theory was instrumental in the development of new housing environment measures, the selection of appropriate research methods, and framing research questions that are building a new empirical base of knowledge about promoting adaptive functioning, health, and recovery for persons with SMI living in community settings.

  8. Investigation of wheat coleoptile response to phototropic stimulations

    NASA Technical Reports Server (NTRS)

    Heathcote, David G.; Brown, Allen H.; Chapman, David K.

    1993-01-01

    This report provides a summary of the preparations for, and the conduct and post-flight data analysis of, the Spacelab flight investigation FOTRAN, which flew on the IML-1 mission (STS-42) in January, 1992. The investigation was designed to provide data on the responses of wheat seedlings to various blue-light stimuli given while the plants were exposed to orbital microgravity conditions. Before the flight, a number of hypotheses were established which were to be tested by the data from the flight and parallel ground studies. A description of the experiment protocol developed for the mission is provided, and an account of the activities supported during preparations for and support of the flight experiment is given. Details of the methods used to reduce and analyze the data from the flight are outlined.

  9. Biological And Ecological Responses Of Macrobenthic Assemblages To Sediment Contamination In French Streams

    NASA Astrophysics Data System (ADS)

    Archaimbault, V.; Garric, J.; Babut, M.; Usseglio-Polatera, P.; Wasson, J.

    2005-05-01

    In order to fit the requirements of the European Water Framework Directive, member states have to quantify the relationships between the biological status and physical and chemical properties of surface waters and to develop validated tools to assess the ecological quality of freshwater ecosystems. With the objectives 1) to describe toxic impact on in situ macrobenthic communities and 2) to identify key biological metrics for describing toxic pressures, the relationships between stream sediment toxicity (concentration of trace elements, PAHs, organochlorine compounds and pesticides) and the functional structure of macrobenthic communities were analysed. Faunal and chemical data were obtained from the French water data network and analysed by multivariate and regression approaches. Combinations of biological and ecological traits were related to faunal changes and compared to sediment contamination. Moreover, the possibility of using these results for predicting the stream ecological status as a function of chemical contamination were examined. The relevance of observed tendencies and pressure/impact relationships will be discussed.

  10. Long-term trends in ecological systems: A basis for understanding responses to global change

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This book presents long-term data and cross-site comparisons from 50 sites in the US, including 26 sites in the Long Term Ecological Research Program, 14 in the USFS, and 7 in the USDA Agricultural Research Service. The intent of this book is twofold: (1) to illustrate the importance of long-term da...

  11. Ecological responses to simulated agricultural runoff in a riverine backwater wetland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Riverine backwater wetlands within river floodplains provide valuable ecological functions such as acting as filters for suspended sediment, nutrients and pesticides entering from adjacent agricultural fields, as well as habitat and refugia for aquatic biota. A 500 m long, 20 m wide riverine backwa...

  12. Tallgrass prairie ants: their species composition, ecological roles, and response to management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ants are highly influential organisms in terrestrial ecosystems, including the tallgrass prairie, one of the most endangered ecosystems in North America. Through their tunneling, ants affect soil properties and resource availability for animals and plants. Ants also have important ecological roles a...

  13. Long-Term Trends in Ecological Systems: A Basis for Understanding Responses to Global Change

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Eco Trends Editorial Committee sorted through vast amounts of historical and ongoing data from 50 ecological sites in the continental United States including Alaska, several islands, and Antarctica to present in a logical format the variables commonly collected. This report presents a subset of...

  14. Response to June Boyce-Tillman, "Towards an Ecology of Music Education"

    ERIC Educational Resources Information Center

    Garberich, Mark

    2004-01-01

    Mark Garberich responds to June Boyce-Tillman's "Towards an Ecology of Music Education," by saying that it challenges the foundations of music education philosophy and its application to practice. Garberich believes that beginning with the identification and clarification of what are described as "subjugated ways of knowing," she advocates the…

  15. Ecological catastrophes: threshold responses to climate, soil, and land use drivers of the dust bowl

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Dust Bowl was one of the largest ecological disasters, yet is among the least well-studied for regional-scale impacts. Much of the central grasslands region (CGR) of North America experienced a multi-year drought in the 1930s that combined with poor land management practices to result in broad-s...

  16. A PERSON-CENTERED AND ECOLOGICAL INVESTIGATION OF ACCULTURATION STRATEGIES IN HISPANIC IMMIGRANT YOUTH

    PubMed Central

    Coatsworth, J. Douglas; Maldonado-Molina, Mildred; Pantin, Hilda; Szapocznik, José

    2006-01-01

    Understanding the processes of acculturation in ethnic minority populations is one of the central tasks of crosscultural research. Addressing challenges of theory, methods, and application in acculturation research requires ongoing advancements in methods and theoretical and model development. The current study was designed to explain a person-centered approach to investigating acculturation and biculturalism and to illustrate this method with a sample of 315 Hispanic youth. Pattern analyses of the Hispanicism and Americanism scores from the Bicultural Involvement Scale yielded four distinct acculturation types, including one characterized by moderate scores on both scales. Relations between acculturation types and indicators of individual, family, and peer adaptation were tested. Results indicated that bicultural youth tended to show the most adaptive pattern of functioning across multiple sociocultural domains. Assimilated youth did not show as strongly negative a pattern as has been reported elsewhere. Implications and benefits of a person-centered approach are discussed. PMID:16799699

  17. A PERSON-CENTERED AND ECOLOGICAL INVESTIGATION OF ACCULTURATION STRATEGIES IN HISPANIC IMMIGRANT YOUTH.

    PubMed

    Coatsworth, J Douglas; Maldonado-Molina, Mildred; Pantin, Hilda; Szapocznik, José

    2005-03-01

    Understanding the processes of acculturation in ethnic minority populations is one of the central tasks of crosscultural research. Addressing challenges of theory, methods, and application in acculturation research requires ongoing advancements in methods and theoretical and model development. The current study was designed to explain a person-centered approach to investigating acculturation and biculturalism and to illustrate this method with a sample of 315 Hispanic youth. Pattern analyses of the Hispanicism and Americanism scores from the Bicultural Involvement Scale yielded four distinct acculturation types, including one characterized by moderate scores on both scales. Relations between acculturation types and indicators of individual, family, and peer adaptation were tested. Results indicated that bicultural youth tended to show the most adaptive pattern of functioning across multiple sociocultural domains. Assimilated youth did not show as strongly negative a pattern as has been reported elsewhere. Implications and benefits of a person-centered approach are discussed. PMID:16799699

  18. The growth response in deepwater rice: Biophysical and ultrastructural investigations

    SciTech Connect

    Kende, H.; Kutshera, U. )

    1989-04-01

    Partial submergence induces rapid internodal elongation in deepwater rice. This response is mediated by ethylene and gibberellin and is based, in part, on enhanced cell elongation. Rapidly growing internodes exhibit increased plastic extensibility of the cell walls and tissue tension. The latter indicates that the outer epidermis is growth limiting. The ultrastructure of the cell wall/plasmalemma interface was investigated in the region where cell elongation takes place. In submerged internodes, electron-dense particles of about 100 nm diameter were found at the outer epidermal cell wall but not at the inner epidermal wall at the inner epidermal walls or the walls of interior cells. They were also not detected at the outer epidermal walls of air-grown internodes. We suggest that these particles are related to growth of the outer epidermis.

  19. An Investigation of Cancer Rates in the Argentia Region, Newfoundland and Labrador: An Ecological Study

    PubMed Central

    Duke, Pauline; Godwin, Marshall; Peach, Mandy; Fortier, Jacqueline; Bornstein, Stephen; Buehler, Sharon; McCrate, Farah; Pike, Andrea; Wang, Peizhong Peter; Cullen, Richard M.

    2015-01-01

    Background. The Argentia region of Newfoundland and Labrador, Canada, was home to a US naval base during a 40-year period between the 1940s and the 1990s. Activities on the base resulted in contamination of the soil and groundwater in the region with chemicals such as heavy metals and dioxins, and residents have expressed concern about higher rates of cancer in their community. This study investigated the rate of cancer diagnosis that is disproportionately high in the Argentia region. Methods. Cases of cancer diagnosed between 1985 and 2011 were obtained for the Argentia region, two comparison communities, and the province of Newfoundland and Labrador. Crude and age-standardized incidence rates of cancer diagnosis were calculated and compared. The crude incidence rate was adjusted for differences in age demographics using census data, and age-standardized incidence rates were compared. Results. Although the Argentia region had a higher crude rate of cancer diagnosis, the age-standardized incidence rate did not differ significantly from the comparison communities or the provincial average. Argentia has an aging population, which may have influenced the perception of increased cancer diagnosis in the community. Conclusions. We did not detect an increased burden of cancer in the Argentia region. PMID:26633979

  20. Skylab/EREP application to ecological, geological and oceanographic investigations of Delaware Bay

    NASA Technical Reports Server (NTRS)

    Klemas, V. (Principal Investigator)

    1974-01-01

    The author has identified the following significant results. NASA's ERTS-1 satellite and Skylab-EREP have both provided imagery suitable for investigating coastal vegetation, land use, current circulation, water turbidity, waste disposal, and sea state. Based on high contrast targets, such as piers and breakwaters, the ERTS-1 MSS seems to have a resolution of 70-100 meters, Skylab's S190A about 30-70 meters, and its S190B about 10-30 meters. Important coastal land use details can be more readily mapped using Skylab's imagery. On the other hand, the regular eighteen day cycle of ERTS-1 allows observation of important man-made and natural changes, and facilitates collection of ground truth. The Skylab/EREP multispectral scanner offers 13 spectral bands as compared to 4 bands on ERTS-1. However, EREP scanner tapes require special filtering to remove several types of noise and their conical line scan pattern must be linearized before small targets can be identified based on spatial features.

  1. Lymphohaematopoietic system cancer incidence in an urban area near a coke oven plant: an ecological investigation

    PubMed Central

    Parodi, S; Vercelli, M; Stella, A; Stagnaro, E; Valerio, F

    2003-01-01

    Aims: To evaluate the incidence risk of lymphohaematopoietic cancers for the 1986–94 period in Cornigliano, a district of Genoa (Italy), where a coke oven is located a few hundred metres from the residential area. Methods: The whole of Genoa and one of its 25 districts (Rivarolo) were selected as controls. The trend of risk around the coke oven was evaluated via Stone's method, while the geographic pattern of such risks across the Cornigliano district was evaluated by computing full Bayes estimates of standardised incidence ratio (FBE-SIR). Results: In males, elevated relative risks (RR) were observed for all lymphohaematopoietic cancers (RR 1.7 v Rivarolo and 1.6 v Genoa), for NHL (RR 2.4 v Rivarolo and 1.7 v Genoa), and for leukaemia (RR 2.4 v Rivarolo and 1.9 v Genoa). In females, statistically non-significant RR were observed. In males no excess of risk was found close to the coke oven. In females, a rising risk for NHL was observed approaching the plant, although statistical significance was not reached, while the risk for leukaemia was not evaluable due to the small number of cases. Analysis of the geographic pattern of risk suggested the presence of a cluster of NHL in both sexes in the eastern part of the district, where a foundry had been operational until the early 1980s. A cluster of leukaemia cases was observed in males in a northern part of the area, where no major sources of benzene seemed to be present. Conclusions: The estimated risks seem to be slightly or not at all related to the distance from the coke oven. The statistically significant higher risks observed in males for NHL and leukaemia, and the clusters of leukaemia in males and of NHL in both sexes deserve further investigations in order to trace the exposures associated with such risks. PMID:12598665

  2. Transcriptome resources for the white-footed mouse (Peromyscus leucopus): new genomic tools for investigating ecologically divergent urban and rural populations.

    PubMed

    Harris, Stephen E; O'Neill, Rachel J; Munshi-South, Jason

    2015-03-01

    Genomic resources are important and attainable for examining evolutionary change in divergent natural populations of nonmodel species. We utilized two next-generation sequencing (NGS) platforms, 454 and SOLiD 5500XL, to assemble low-coverage transcriptomes of the white-footed mouse (Peromyscus leucopus), a widespread and abundant native rodent in eastern North America. We sequenced liver mRNA transcripts from multiple individuals collected from urban populations in New York City and rural populations in undisturbed protected areas nearby and assembled a reference transcriptome using 1 080 065 954 SOLiD 5500XL (75 bp) reads and 3 052 640 454 GS FLX + reads. The reference contained 40 908 contigs with a N50 = 1044 bp and a total content of 30.06 Megabases (Mb). Contigs were annotated from Mus musculus (39.96% annotated) Uniprot databases. We identified 104 655 high-quality single nucleotide polymorphisms (SNPs) and 65 single sequence repeats (SSRs) with flanking primers. We also used normalized read counts to identify putative gene expression differences in 10 genes between populations. There were 19 contigs significantly differentially expressed in urban populations compared to rural populations, with gene function annotations generally related to the translation and modification of proteins and those involved in immune responses. The individual transcriptomes generated in this study will be used to investigate evolutionary responses to urbanization. The reference transcriptome provides a valuable resource for the scientific community using North American Peromyscus species as emerging model systems for ecological genetics and adaptation. PMID:24980186

  3. Transcriptome resources for the white-footed mouse (Peromyscus leucopus): new genomic tools for investigating ecologically divergent urban and rural populations.

    PubMed

    Harris, Stephen E; O'Neill, Rachel J; Munshi-South, Jason

    2015-03-01

    Genomic resources are important and attainable for examining evolutionary change in divergent natural populations of nonmodel species. We utilized two next-generation sequencing (NGS) platforms, 454 and SOLiD 5500XL, to assemble low-coverage transcriptomes of the white-footed mouse (Peromyscus leucopus), a widespread and abundant native rodent in eastern North America. We sequenced liver mRNA transcripts from multiple individuals collected from urban populations in New York City and rural populations in undisturbed protected areas nearby and assembled a reference transcriptome using 1 080 065 954 SOLiD 5500XL (75 bp) reads and 3 052 640 454 GS FLX + reads. The reference contained 40 908 contigs with a N50 = 1044 bp and a total content of 30.06 Megabases (Mb). Contigs were annotated from Mus musculus (39.96% annotated) Uniprot databases. We identified 104 655 high-quality single nucleotide polymorphisms (SNPs) and 65 single sequence repeats (SSRs) with flanking primers. We also used normalized read counts to identify putative gene expression differences in 10 genes between populations. There were 19 contigs significantly differentially expressed in urban populations compared to rural populations, with gene function annotations generally related to the translation and modification of proteins and those involved in immune responses. The individual transcriptomes generated in this study will be used to investigate evolutionary responses to urbanization. The reference transcriptome provides a valuable resource for the scientific community using North American Peromyscus species as emerging model systems for ecological genetics and adaptation.

  4. “My Worries Are Rational, Climate Change Is Not”: Habitual Ecological Worrying Is an Adaptive Response

    PubMed Central

    Verplanken, Bas; Roy, Deborah

    2013-01-01

    Qualifications such as “global warming hysteria” and “energy policy schizophrenia” put forward by some climate change skeptics, usually outside the academic arena, may suggest that people who seriously worry about the environment suffer from psychological imbalance. The present study aimed to refute this thesis. While habitual worrying in general is strongly associated with psychopathological symptoms, in a survey a near-zero correlation was found between habitual ecological worrying and pathological worry. Instead, habitual ecological worrying was associated with pro-environmental attitudes and behaviors, and with a personality structure characterized by imagination and an appreciation for new ideas. The study had sufficient statistical power and measures were valid and reliable. The results confirm that those who habitually worry about the ecology are not only lacking in any psychopathology, but demonstrate a constructive and adaptive response to a serious problem. In the public domain, these findings may contribute to a more rational and less emotional debate on climate change and to the prevention of stigmatization of people who are genuinely concerned about our habitat and are prepared to do something about it (“habitual worriers are not crazy”). In the academic arena this study may contribute to environmental psychology (“habitual worrying is part of a green identity”), as well as to the literature on worry and anxiety (“habitual worrying can be a constructive response”). PMID:24023958

  5. The natural vegetation responses to the groundwater change resulting from ecological water conveyances to the lower Tarim River.

    PubMed

    Xu, Hailiang; Ye, Mao; Song, Yudong; Chen, Yaning

    2007-08-01

    This paper takes the ecological water conveyance project (EWCP) that transfers water from the Bosten Lake, to Daxihaizi Reservoir, and finally to the Taitema Lake as a case study to analyze the dynamic change of the groundwater depth, the vegetation responses to the elevation of the groundwater depth as well as the relationship between the groundwater depth and the natural vegetation. The results from many years' monitoring in field indicate: (1) the groundwater depth has been elevating gradually with the increase in the times of watering and the elevation range has been expanding continuously in the lower reaches of Tarim River. Correspondingly, the natural vegetation has a favorable response to the elevation of the groundwater depth. The change of the natural vegetation has accordance with that of the groundwater depth. Such facts not only show that groundwater is a key factor to the growth of the native vegetation but also prove it is feasible that the degraded ecosystem can be restored and protected by the EWCP; (2) the results of analysis of the spatial-temporal response of the natural vegetation to watering reveals that the beneficial influence of the EWCP on the ecosystem in the lower Tarim River is a long-term process; (3) in terms of the function and structure of ecosystem after watering in the lower reaches of Tarim River, the EWCP does not still reach the goal of ecological restoration at a large spatial scale at present. Based on such monitoring results, some countermeasures and suggestions for the future restoration strategy are proposed so as to provide a theoretical basis for restoring and protecting the ecosystem in Tarim River, and meanwhile it can also provide some scientific references for implementing the similar ecological projects in other areas.

  6. Glaciological investigations on modern ice sheet response in South Greenland

    NASA Astrophysics Data System (ADS)

    Mayer, C.; Bøggild, C. E.; Podlech, S.; Olesen, O. B.

    2003-04-01

    The reaction of the large ice sheets to global climate change is still in the focus of scientific debate. Recent investigations have shown pronounced thinning in the southern part of the Greenland Ice Sheet. In order to investigate the cause of the observed thinning in this area and to judge the sensitivity of this part of the ice sheet a combined field work, remote sensing and modelling project was designed. A glaciological transect was established in May 2001 on one of the main outlet glaciers in South Greenland, where the first data series have been collected. This transect aims on monitoring the modern climatic conditions in an area of the ice sheet which is strongest affected by the recently observed thinning. A mass balance/elevation relation has been calculated from the field data, which is used as input to a regional ice dynamic model for investigating the dynamic conditions of this area. Modelled surface velocities are compared to GPS field measurements in order to constrain model parameters. Results show that the sensitivity of the ice sheet to climatic changes varies considerably along the southern margin. The history of the glacier variations in the same area during the last 40 years has been reconstructed on the basis of aerial photographs and satellite images. Comparing the development of the retreat in this area over the last decades with the maximum extent of the ice sheet from the 1890s indicates a strong increase in the recession of the margin. The estimated thinning from these observations is in good agreement with the recent laser altimeter measurements. The observed surface lowering is also responsible for the fast disintegration of several glacier tongues of tide water glaciers in the area.

  7. Dispositional drinking motives: associations with appraised alcohol effects and alcohol consumption in an ecological momentary assessment investigation.

    PubMed

    Piasecki, Thomas M; Cooper, M Lynne; Wood, Phillip K; Sher, Kenneth J; Shiffman, Saul; Heath, Andrew C

    2014-06-01

    Alcohol use can be understood as a strategic behavior, such that people choose to drink based on the anticipated affective changes produced by drinking relative to those produced by alternative behaviors. This study investigated whether people who report drinking for specific reasons via the Drinking Motives Questionnaire-Revised (DMQ-R; Cooper, 1994) actually experience the alcohol effects they purportedly seek. As a secondary goal, we examined relations between drinking motives and indices of the amount of alcohol consumed. Data were drawn from 3,272 drinking episodes logged by 393 community-recruited drinkers during a 21-day Ecological Momentary Assessment investigation. After accounting for selected covariates, DMQ-R enhancement motives uniquely predicted real-time reports of enhanced drinking pleasure. DMQ-R coping motives were associated with reports of increased drinking-contingent relief and punishment. Enhancement motives uniquely predicted consuming more drinks per episode and higher peak intra-episode estimated blood alcohol concentration. The findings extend the evidence for the validity of the DMQ-R motive scores by demonstrating that internal drinking motives (enhancement and coping) are related to the experienced outcomes of drinking in the manner anticipated by theory.

  8. Daily life functioning of community-dwelling elderly couples: an investigation of the feasibility and validity of Ecological Momentary Assessment.

    PubMed

    Rullier, Laetitia; Atzeni, Thierry; Husky, Mathilde; Bouisson, Jean; Dartigues, Jean-François; Swendsen, Joel; Bergua, Valerie

    2014-06-01

    Although ambulatory data collection techniques have been used in elderly populations, their feasibility and validity amongst elderly individuals with cognitive impairment and amongst couples remains unexplored. The main objective of this study is to examine the validity of Ecological Momentary Assessment (EMA) in elderly persons with or without cognitive impairment and their spouses. The sample included 58 retired farmers (mean 77.3 years, standard deviation [SD] 5.5) with or without cognitive impairment, recruited within a French cohort and 60 spouses (mean 73.4 years, SD 6.9). The presence of cognitive impairment determining by a panel of specialized neurologists permitted to define two groups: "The Cognitive Impairment Group" and "The Control Group". EMA procedures consisted of repeated telephone interviews five times per day during four days for each spouse. Our results demonstrate the validity of EMA procedures through a 92.1% level of compliance, the absence of fatigue effects, and the lack of evidence for major reactivity to the methods. However, the specificity of our sample may explain the acceptance (42%) and response (75%) rates and may reduce the generalizability of the results to the general population of elderly individuals. Finally, the validation of such techniques may contribute to future research examining community-dwelling elderly individuals and their spouses.

  9. Investigation of cellular responses upon interaction with silver nanoparticles

    PubMed Central

    Subbiah, Ramesh; Jeon, Seong Beom; Park, Kwideok; Ahn, Sang Jung; Yun, Kyusik

    2015-01-01

    In order for nanoparticles (NPs) to be applied in the biomedical field, a thorough investigation of their interactions with biological systems is required. Although this is a growing area of research, there is a paucity of comprehensive data in cell-based studies. To address this, we analyzed the physicomechanical responses of human alveolar epithelial cells (A549), mouse fibroblasts (NIH3T3), and human bone marrow stromal cells (HS-5), following their interaction with silver nanoparticles (AgNPs). When compared with kanamycin, AgNPs exhibited moderate antibacterial activity. Cell viability ranged from ≤80% at a high AgNPs dose (40 µg/mL) to >95% at a low dose (10 µg/mL). We also used atomic force microscopy-coupled force spectroscopy to evaluate the biophysical and biomechanical properties of cells. This revealed that AgNPs treatment increased the surface roughness (P<0.001) and stiffness (P<0.001) of cells. Certain cellular changes are likely due to interaction of the AgNPs with the cell surface. The degree to which cellular morphology was altered directly proportional to the level of AgNP-induced cytotoxicity. Together, these data suggest that atomic force microscopy can be used as a potential tool to develop a biomechanics-based biomarker for the evaluation of NP-dependent cytotoxicity and cytopathology. PMID:26346562

  10. Investigation of cellular responses upon interaction with silver nanoparticles.

    PubMed

    Subbiah, Ramesh; Jeon, Seong Beom; Park, Kwideok; Ahn, Sang Jung; Yun, Kyusik

    2015-01-01

    In order for nanoparticles (NPs) to be applied in the biomedical field, a thorough investigation of their interactions with biological systems is required. Although this is a growing area of research, there is a paucity of comprehensive data in cell-based studies. To address this, we analyzed the physicomechanical responses of human alveolar epithelial cells (A549), mouse fibroblasts (NIH3T3), and human bone marrow stromal cells (HS-5), following their interaction with silver nanoparticles (AgNPs). When compared with kanamycin, AgNPs exhibited moderate antibacterial activity. Cell viability ranged from ≤ 80% at a high AgNPs dose (40 µg/mL) to >95% at a low dose (10 µg/mL). We also used atomic force microscopy-coupled force spectroscopy to evaluate the biophysical and biomechanical properties of cells. This revealed that AgNPs treatment increased the surface roughness (P<0.001) and stiffness (P<0.001) of cells. Certain cellular changes are likely due to interaction of the AgNPs with the cell surface. The degree to which cellular morphology was altered directly proportional to the level of AgNP-induced cytotoxicity. Together, these data suggest that atomic force microscopy can be used as a potential tool to develop a biomechanics-based biomarker for the evaluation of NP-dependent cytotoxicity and cytopathology. PMID:26346562

  11. Ecological changes in Coyotes (Canis latrans) in response to the ice age megafaunal extinctions.

    PubMed

    Meachen, Julie A; Janowicz, Adrianna C; Avery, Jori E; Sadleir, Rudyard W

    2014-01-01

    Coyotes (Canis latrans) are an important species in human-inhabited areas. They control pests and are the apex predators in many ecosystems. Because of their importance it is imperative to understand how environmental change will affect this species. The end of the Pleistocene Ice Age brought with it many ecological changes for coyotes and here we statistically determine the changes that occurred in coyotes, when these changes occurred, and what the ecological consequences were of these changes. We examined the mandibles of three coyote populations: Pleistocene Rancho La Brean (13-29 Ka), earliest Holocene Rancho La Brean (8-10 Ka), and Recent from North America, using 2D geometric morphometrics to determine the morphological differences among them. Our results show that these three populations were morphologically distinct. The Pleistocene coyotes had an overall robust mandible with an increased shearing arcade and a decreased grinding arcade, adapted for carnivory and killing larger prey; whereas the modern populations show a gracile morphology with a tendency toward omnivory or grinding. The earliest Holocene populations are intermediate in morphology and smallest in size. These findings indicate that a niche shift occurred in coyotes at the Pleistocene/Holocene boundary - from a hunter of large prey to a small prey/more omnivorous animal. Species interactions between Canis were the most likely cause of this transition. This study shows that the Pleistocene extinction event affected species that did not go extinct as well as those that did.

  12. Ecological Changes in Coyotes (Canis latrans) in Response to the Ice Age Megafaunal Extinctions

    PubMed Central

    Meachen, Julie A.; Janowicz, Adrianna C.; Avery, Jori E.; Sadleir, Rudyard W.

    2014-01-01

    Coyotes (Canis latrans) are an important species in human-inhabited areas. They control pests and are the apex predators in many ecosystems. Because of their importance it is imperative to understand how environmental change will affect this species. The end of the Pleistocene Ice Age brought with it many ecological changes for coyotes and here we statistically determine the changes that occurred in coyotes, when these changes occurred, and what the ecological consequences were of these changes. We examined the mandibles of three coyote populations: Pleistocene Rancho La Brean (13–29 Ka), earliest Holocene Rancho La Brean (8–10 Ka), and Recent from North America, using 2D geometric morphometrics to determine the morphological differences among them. Our results show that these three populations were morphologically distinct. The Pleistocene coyotes had an overall robust mandible with an increased shearing arcade and a decreased grinding arcade, adapted for carnivory and killing larger prey; whereas the modern populations show a gracile morphology with a tendency toward omnivory or grinding. The earliest Holocene populations are intermediate in morphology and smallest in size. These findings indicate that a niche shift occurred in coyotes at the Pleistocene/Holocene boundary – from a hunter of large prey to a small prey/more omnivorous animal. Species interactions between Canis were the most likely cause of this transition. This study shows that the Pleistocene extinction event affected species that did not go extinct as well as those that did. PMID:25551387

  13. The evolution of bet hedging in response to local ecological conditions.

    PubMed

    Rajon, Etienne; Desouhant, Emmanuel; Chevalier, Mathieu; Débias, François; Menu, Frédéric

    2014-07-01

    Genotypes that hedge their bets can be favored by selection in an unpredictably varying environment. Bet hedging can be achieved by systematically expressing several phenotypes, such as one that readily attempts to reproduce and one that procrastinates in a dormant stage. But how much of each phenotype should a genotype express? Theory predicts that evolving bet-hedging strategies depend on local environmental variation, on how the population is regulated, and on exchanges with neighboring populations. Empirically, however, it remains unknown whether bet hedging can evolve to cope with the ecological conditions experienced by populations. Here we study the evolution of bet-hedging dormancy frequencies in two neighboring populations of the chestnut weevil, Curculio elephas. We estimate the temporal distribution of demographic parameters together with the form of the relationship between fecundity and population density and use both to parameterize models that predict the bet-hedging dormancy frequency expected to evolve in each population. Strikingly, the observed dormancy frequencies closely match predictions in their respective localities. We also found that dormancy frequencies vary randomly across generations, likely due to environmental perturbations of the underlying physiological mechanism. Using a model that includes these constraints, we predict the whole distribution of dormancy frequencies whose mean and shape agree with our observed data. Overall, our results suggest that dormancy frequencies have evolved according to local ecological conditions and physiological constraints.

  14. Modeling post-fledging survival of lark buntings in response to ecological and biological factors

    USGS Publications Warehouse

    Yackel Adams, A.A.; Skagen, S.K.; Savidge, J.A.

    2006-01-01

    We evaluated the influences of several ecological, biological, and methodological factors on post-fledging survival of a shortgrass prairie bird, the Lark Bunting (Calamospiza melanocorys). We estimated daily post-fledging survival (n = 206, 82 broods) using radiotelemetry and color bands to track fledglings. Daily survival probabilities were best explained by drought intensity, time in season (quadratic trend), ages a??3 d post-fledging, and rank given drought intensity. Drought intensity had a strong negative effect on survival. Rank was an important predictor of fledgling survival only during the severe drought of 2002 when the smallest fledglings had lower survival. Recently fledged young (ages a??3 d post-fledging) undergoing the transition from nest to surrounding habitat experienced markedly lower survival, demonstrating the vulnerable nature of this time period. Survival was greater in mid and late season than early season, corresponding to our assumptions of food availability. Neither mark type nor sex of attending parent influenced survival. The model-averaged product of the 22-d survival calculated using mean rank and median value of time in season was 0.360 A? 0.08 in 2001 and 0.276 A? 0.08 in 2002. Survival estimates that account for age, condition of young, ecological conditions, and other factors are important for parameterization of realistic population models. Biologists using population growth models to elucidate mechanisms of population declines should attempt to estimate species-specific of post-fledging survival rather than use generalized estimates.

  15. No Boundaries: Genomes, Organisms, and Ecological Interactions Responsible for Divergence and Reproductive Isolation

    PubMed Central

    2014-01-01

    Revealing the genetic basis of traits that cause reproductive isolation, particularly premating or sexual isolation, usually involves the same challenges as most attempts at genotype–phenotype mapping and so requires knowledge of how these traits are expressed in different individuals, populations, and environments, particularly under natural conditions. Genetic dissection of speciation phenotypes thus requires understanding of the internal and external contexts in which underlying genetic elements are expressed. Gene expression is a product of complex interacting factors internal and external to the organism including developmental programs, the genetic background including nuclear–cytotype interactions, epistatic relationships, interactions among individuals or social effects, stochasticity, and prevailing variation in ecological conditions. Understanding of genomic divergence associated with reproductive isolation will be facilitated by functional expression analysis of annotated genomes in organisms with well-studied evolutionary histories, phylogenetic affinities, and known patterns of ecological variation throughout their life cycles. I review progress and prospects for understanding the pervasive role of host plant use on genetic and phenotypic expression of reproductive isolating mechanisms in cactophilic Drosophila mojavensis and suggest how this system can be used as a model for revealing the genetic basis for species formation in organisms where speciation phenotypes are under the joint influences of genetic and environmental factors. PMID:25149252

  16. Ecological changes in Coyotes (Canis latrans) in response to the ice age megafaunal extinctions.

    PubMed

    Meachen, Julie A; Janowicz, Adrianna C; Avery, Jori E; Sadleir, Rudyard W

    2014-01-01

    Coyotes (Canis latrans) are an important species in human-inhabited areas. They control pests and are the apex predators in many ecosystems. Because of their importance it is imperative to understand how environmental change will affect this species. The end of the Pleistocene Ice Age brought with it many ecological changes for coyotes and here we statistically determine the changes that occurred in coyotes, when these changes occurred, and what the ecological consequences were of these changes. We examined the mandibles of three coyote populations: Pleistocene Rancho La Brean (13-29 Ka), earliest Holocene Rancho La Brean (8-10 Ka), and Recent from North America, using 2D geometric morphometrics to determine the morphological differences among them. Our results show that these three populations were morphologically distinct. The Pleistocene coyotes had an overall robust mandible with an increased shearing arcade and a decreased grinding arcade, adapted for carnivory and killing larger prey; whereas the modern populations show a gracile morphology with a tendency toward omnivory or grinding. The earliest Holocene populations are intermediate in morphology and smallest in size. These findings indicate that a niche shift occurred in coyotes at the Pleistocene/Holocene boundary - from a hunter of large prey to a small prey/more omnivorous animal. Species interactions between Canis were the most likely cause of this transition. This study shows that the Pleistocene extinction event affected species that did not go extinct as well as those that did. PMID:25551387

  17. Ecological limit functions relating fish community response to hydrologic departures of the ecological flow regime in the Tennessee River basin, United States

    USGS Publications Warehouse

    Knight, Rodney R.; Murphy, Jennifer C.; Wolfe, William J.; Saylor, Charles F.; Wales, Amy K.

    2014-01-01

      Use of ecological limit functions to make decisions regarding proposed hydrologic regime changes, although commonly presented as a management tool, is not as straightforward or informative as often assumed. We contend that statistical evaluation of the internal wedge structure below limit functions may provide a probabilistic understanding of how aquatic ecology is influenced by altered hydrology and may serve as the basis for evaluating the potential effect of proposed hydrologic changes.

  18. 21 CFR 812.100 - General responsibilities of investigators.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... investigation is conducted according to the signed agreement, the investigational plan and applicable FDA regulations, for protecting the rights, safety, and welfare of subjects under the investigator's care, and...

  19. 21 CFR 812.100 - General responsibilities of investigators.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... investigation is conducted according to the signed agreement, the investigational plan and applicable FDA regulations, for protecting the rights, safety, and welfare of subjects under the investigator's care, and...

  20. 21 CFR 812.100 - General responsibilities of investigators.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... investigation is conducted according to the signed agreement, the investigational plan and applicable FDA regulations, for protecting the rights, safety, and welfare of subjects under the investigator's care, and...

  1. 21 CFR 812.100 - General responsibilities of investigators.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... investigation is conducted according to the signed agreement, the investigational plan and applicable FDA regulations, for protecting the rights, safety, and welfare of subjects under the investigator's care, and...

  2. 21 CFR 812.100 - General responsibilities of investigators.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... investigation is conducted according to the signed agreement, the investigational plan and applicable FDA regulations, for protecting the rights, safety, and welfare of subjects under the investigator's care, and...

  3. Using Ecological Momentary Assessment to Investigate Short-Term Variations in Sexual Functioning in a Sample of Peri-Menopausal Women from Iran

    PubMed Central

    Pakpour, Amir H.; Yekaninejad, Mir Saeed; Pallich, Gianandrea; Burri, Andrea

    2015-01-01

    The investigation of short-term changes in female sexual functioning has received little attention so far. The aims of the study were to gain empirical knowledge on within-subject and within- and across-variable fluctuations in women’s sexual functioning over time. More specifically, to investigate the stability of women´s self-reported sexual functioning and the moderating effects of contextual and interpersonal factors. A convenience sample of 206 women, recruited across eight Health care Clinics in Rasht, Iran. Ecological momentary assessment was used to examine fluctuations of sexual functioning over a six week period. A shortened version of the Female Sexual Function Index (FSFI) was applied to assess sexual functioning. Self-constructed questions were included to assess relationship satisfaction, partner’s sexual performance and stress levels. Mixed linear two-level model analyses revealed a link between orgasm and relationship satisfaction (Beta = 0.125, P = 0.074) with this link varying significantly between women. Analyses further revealed a significant negative association between stress and all six domains of women’s sexual functioning. Women not only reported differing levels of stress over the course of the assessment period, but further differed from each other in how much stress they experienced and how much this influenced their sexual response. Orgasm and sexual satisfaction were both significantly associated with all other domains of sexual function (P<0.001). And finally, a link between partner performance and all domains of women`s sexual functioning (P<0.001) could be detected. Except for lubrication (P = 0.717), relationship satisfaction had a significant effect on all domains of the sexual response (P<0.001). Overall, our findings support the new group of criteria introduced in the DSM-5, called “associated features” such as partner factors and relationship factors. Consideration of these criteria is important and necessary for

  4. Response of dissolved oxygen and related marine ecological parameters to a tropical cyclone in the South China Sea

    NASA Astrophysics Data System (ADS)

    Lin, Jingrou; Tang, Danling; Alpers, Werner; Wang, Sufen

    2014-04-01

    It is well known that tropical cyclones can cause upwelling, decrease of sea surface temperature, increase of chlorophyll-a (Chl-a) concentration and enhancement of primary production. But little is known about the response of dissolved oxygen (DO) concentration to a typhoon in the open ocean. This paper investigates the impact of a typhoon on DO concentration and related ecological parameters using in situ and remote sensing data. The in situ data were collected 1 week after the passage of the super-typhoon Nanmadol in the northern South China Sea in 2011. An increase in DO concentration, accompanied by a decrease in water temperature and an increase in salinity and Chl-a concentration, was measured at sampling stations close to the typhoon track. At these stations, maximum DO concentration was found at a depth of around 5 m and maximum Chl-a concentration at depths between 50 and 75 m. The layer of high DO concentration extends from the surface to a depth of 35 m and the concentrations stay almost constant down to this depth. Due to the passage of the typhoon, also a large sea level anomaly (21.6 cm) and a high value of Ekman pumping velocity (4.0 × 10-4 m s-1) are observed, indicating upwelling phenomenon. At the same time, also intrusion of Kuroshio waters in the form of a loop current into the South China Sea (SCS) was observed. We attribute the increase of DO concentration after the passage of the typhoon to three effects: (1) entrainment of oxygen from the air into the upper water layer and strong vertical mixing of the water body due to the typhoon winds, (2) upwelling of cold nutrient-rich water which stimulates photosynthesis of phytoplankton and thus the generation of oxygen, which also increases the DO concentration due to cold water since the solubility of oxygen increase with decreasing water temperature, and, possibly, (3) transport of DO enriched waters from the Western Pacific to the SCS via the intrusion of Kuroshio waters.

  5. Seeing the Wood for the Trees: Applying the Dual-Memory System Model to Investigate Expert Teachers' Observational Skills in Natural Ecological Learning Environments

    ERIC Educational Resources Information Center

    Stolpe, Karin; Bjorklund, Lars

    2012-01-01

    This study aims to investigate two expert ecology teachers' ability to attend to essential details in a complex environment during a field excursion, as well as how they teach this ability to their students. In applying a cognitive dual-memory system model for learning, we also suggest a rationale for their behaviour. The model implies two…

  6. Biotic response to late Quaternary rapid climate switches in Santa Barbara Basin: Ecological and evolutionary implications

    SciTech Connect

    Cannariato, K.G.; Kennett, J.P.; Behl, R.J.

    1999-01-01

    Benthic foraminiferal assemblages from Santa Barbara Basin exhibit major faunal and ecological switches associated with late Quaternary millennial- to decadal-scale global climate oscillations. Repeated turnovers of entire faunas occurred rapidly (<40--400 yr) without extinction or speciation in conjunction with Dansgaard-Oeschger shifts in thermohaline circulation, ventilation, and climate, confirming evolutionary model predictions of Roy et al. Consistent faunal successions of dysoxic taxa during successive interstadials reflect the extreme sensitivity and adaptation of the benthic ecosystem to the rapid environmental changes that marked the late Quaternary and possibly other transitional intervals in the history of the Earth`s ocean-atmosphere-cryosphere system. These data support the hypothesis that broad segments of the biosphere are well adapted to rapid climate change.

  7. Ecological scale of bird community response to piñon-juniper removal

    USGS Publications Warehouse

    Knick, Steven T.; Hanser, Steven E.; Leu, Matthias

    2014-01-01

    Piñon (Pinus spp.) and juniper (Juniperus spp.) removal is a common management approach to restore sagebrush (Artemisia spp.) vegetation in areas experiencing woodland expansion. Because many management treatments are conducted to benefit sagebrush-obligate birds, we surveyed bird communities to assess treatment effectiveness in establishing sagebrush bird communities at study sites in Utah, Nevada, Idaho, and Oregon. Our analyses included data from 1 or 2 yr prior to prescribed fire or mechanical treatment and 3 to 5 yr posttreatment. We used detrended correspondence analysis to 1) identify primary patterns of bird communities surveyed from 2006 to 2011 at point transects, 2) estimate ecological scale of change needed to achieve treatment objectives from the relative dissimilarity of survey points to the ordination region delineating sagebrush bird communities, and 3) measure changes in pre- and posttreatment bird communities. Birds associated with sagebrush, woodlands, and ecotones were detected on our surveys; increased dissimilarity of survey points to the sagebrush bird community was characterized by a gradient of increased juniper and decreased sagebrush cover. Prescribed fires burned between 30% and 97% of our bird survey points. However, from 6% to 24% cover of piñon-juniper still remained posttreatment on the four treatment plots. We measured only slight changes in bird communities, which responded primarily to current vegetation rather than relative amount of change from pretreatment vegetation structure. Bird communities at survey points located at greater ecological scales from the sagebrush bird community changed least and will require more significant impact to achieve changes. Sagebrush bird communities were established at only two survey points, which were adjacent to a larger sagebrush landscape and following almost complete juniper removal by mechanical treatment. Our results indicate that management treatments that leave residual woodland cover

  8. Response of plankton ecology and the carbon cycle to climate change over the 21st century

    NASA Astrophysics Data System (ADS)

    Marinov, I.; Doney, S.; Lima, I.; Lindsey, K.; Moore, K.

    2008-12-01

    Here we analyze the impact of climate change on ocean plankton ecology and the carbon cycle over the 21st century using a multi-decadal (1880-2100) experiment conducted with the latest version of the Community Climate System Model (CCSM-3.1) coupled ocean-atmosphere-land-ice model. The oceanic ecosystem model component includes three classes of phytoplankton (diatoms, pico/nano plankton, diazotrophs) and one class of zooplankton which grazes differentially on the phytoplankton groups. The competition between phytoplankton groups is altered by climate-induced changes in nutrients, light and zooplankton. Here we connect the resulting changes in the ecosystem structure to changes in the air-sea CO2 fluxes and the global ocean sink. Long-term trends due to anthropogenic changes are compared to the natural variability of the system. Increasing stratification in the northern hemisphere oceans decreases the nutrient supply to the ocean surface and decreases the relative and absolute diatom abundance. The northern hemisphere shift from diatoms to small phytoplankton results in decreases in total primary production, export production and export ratio, and a shift to a more efficiently recycled, lower biomass euphotic layer. By contrast, an increase in Southern Ocean westerlies acts against increasing temperature and freshwater flux to destratify the water-column. Additionally, the wind-driven poleward shift in the Southern Ocean subpolar-subtropical front results in a southward shift and increase in the largest oceanic diatom bloom. In the Southern Ocean diatoms are favored over small phytoplankton on average, acting to increase total chlorophyll, primary production and export production. The impact of these ecological shifts on the global oceanic carbon sink is complex, with northern and southern hemisphere effects partially compensating each other. In the net, total chlorophyll, primary and export production decrease, but less than previous modeling studies have suggested

  9. A replicated climate change field experiment reveals rapid evolutionary response in an ecologically important soil invertebrate.

    PubMed

    Bataillon, Thomas; Galtier, Nicolas; Bernard, Aurelien; Cryer, Nicolai; Faivre, Nicolas; Santoni, Sylvain; Severac, Dany; Mikkelsen, Teis N; Larsen, Klaus S; Beier, Claus; Sørensen, Jesper G; Holmstrup, Martin; Ehlers, Bodil K

    2016-07-01

    Whether species can respond evolutionarily to current climate change is crucial for the persistence of many species. Yet, very few studies have examined genetic responses to climate change in manipulated experiments carried out in natural field conditions. We examined the evolutionary response to climate change in a common annelid worm using a controlled replicated experiment where climatic conditions were manipulated in a natural setting. Analyzing the transcribed genome of 15 local populations, we found that about 12% of the genetic polymorphisms exhibit differences in allele frequencies associated to changes in soil temperature and soil moisture. This shows an evolutionary response to realistic climate change happening over short-time scale, and calls for incorporating evolution into models predicting future response of species to climate change. It also shows that designed climate change experiments coupled with genome sequencing offer great potential to test for the occurrence (or lack) of an evolutionary response. PMID:27109012

  10. An Investigation of Response Bias in the Chapman Scales.

    ERIC Educational Resources Information Center

    Peltier, B. David; Walsh, James A.

    1990-01-01

    The major response sets that can adversely affect the validity and usefulness of trait scales are briefly described. Using data from 228 college students, representative response set measures were then used to assess the degree to which scores on 4 of the Chapman Scales are determined by content-irrelevant factors. (TJH)

  11. Investigation of Response Changes in the GRE Revised General Test

    ERIC Educational Resources Information Center

    Liu, Ou Lydia; Bridgeman, Brent; Gu, Lixiong; Xu, Jun; Kong, Nan

    2015-01-01

    Research on examinees' response changes on multiple-choice tests over the past 80 years has yielded some consistent findings, including that most examinees make score gains by changing answers. This study expands the research on response changes by focusing on a high-stakes admissions test--the Verbal Reasoning and Quantitative Reasoning measures…

  12. Reinforcement Sensitivity and Responsiveness to Performance Feedback: A Preliminary Investigation

    ERIC Educational Resources Information Center

    Lovett, Benjamin J.; Eckert, Tanya L.

    2009-01-01

    Variability in responsiveness to academic interventions is a common phenomenon in school psychology practice, but the variables associated with this responsiveness are not well understood. Reinforcement sensitivity, a generalized tendency to learn quickly in reward contingency situations, is one variable for increased understanding. In the present…

  13. A system for identifying and investigating unexpected response to treatment

    PubMed Central

    Ozery-Flato, Michal; Ein-Dor, Liat; Neuvirth, Hani; Parush, Naama; Kohn, Martin S.; Hu, Jianying; Aharonov, Ranit

    2015-01-01

    The availability of electronic health records creates fertile ground for developing computational models for various medical conditions. Using machine learning, we can detect patients with unexpected responses to treatment and provide statistical testing and visualization tools to help further analysis. The new system was developed to help researchers uncover new features associated with reduced response to treatment, and to aid physicians in identifying patients that are not responding to treatment as expected and hence deserve more attention. The solution computes a statistical score for the deviation of a given patient’s response from responses observed individuals with similar characteristics and medication regimens. Statistical tests are then applied to identify clinical features that correlate with cohorts of patients showing deviant responses. The results provide comprehensive visualizations, both at the cohort and the individual patient levels. We demonstrate the utility of this system in a population of diabetic patients. PMID:26306256

  14. Theoretical investigation of the oceanic inverted barometer response

    NASA Technical Reports Server (NTRS)

    Dickman, S. R.

    1988-01-01

    Dynamic tidal theory is generalized in order to predict the oceanic response to atmospheric pressure variations. The oceans are found to exhibit distinct dynamic behavior when forced at periods less than one week; depending on the harmonic type of forcing, the amplitude of the response can differ by about 20 percent or more from the static response. Even at roughly two months the traditional 'inverted barometer' may not be sufficiently accurate for applications in which detection of long-term sea level trends or vertical crustal motion is the goal. For forcing at periods of order one year the oceanic response differs by at most a few percent from the static (not the inverted barometer) response; thus calculations of meteorological excitation of the annual and Chandler wobbles can employ the static approximation without reservation.

  15. Shade tolerance plasticity in response to neutral vs green shade cues in Polygonum species of contrasting ecological breadth.

    PubMed

    Griffith, Timothy M; Sultan, Sonia E

    2005-04-01

    Here we examined species differences in perception and response to two distinct types of shade cue, reduced photosynthetically active radiation (PAR) with and without reduced red : far red ratio (R : FR), in Polygonum persicaria and Polygonum hydropiper, two closely related annuals of contrasting ecological breadth. We compared plasticity data for light-gathering traits from glasshouse experiments at equivalently reduced PAR under neutral shade (R : FR 1.03) and green shade (R : FR 0.702). Species shared the ability to distinguish between the two types of shade, as shown by the ability of each to respond differently to neutral vs green shade for one or more traits. However, the species' responses to these cues differed significantly. Polygonum persicaria expressed stronger shade-tolerance responses (increased leaf allocation and leaf area ratio) to reduced PAR alone than to green shade. By contrast, P. hydropiper expressed slightly less plasticity for these traits in neutral than in green shade. The pronounced plastic response of P. persicaria to neutral shade may contribute to the range of habitats this widespread species can occupy, which includes neutral-shade environments such as urban settings.

  16. Responses to climate and economic risks and opportunities across national and ecological boundaries: changing household strategies on the Mongolian plateau

    PubMed Central

    Brown, Daniel G.; Agrawal, Arun; Sass, Daniel A.; Wang, Jun; Hua, Jin; Xie, Yichun

    2013-01-01

    Climate changes on the Mongolian Plateau are creating new challenges for the households and communities of the region. Much of the existing research on household choices in response to climate variability and change focuses on environmental risks and stresses. In contrast, our analysis highlights the importance of taking into account environmental and economic opportunities in explaining household adaptation choices. We surveyed over 750 households arrayed along an ecological gradient and matched across the national border in Mongolia and the Inner Mongolia Autonomous Region, China, asking what changes in livelihoods strategies households made over the last ten years, and analyzed these choices in two broad categories of options: diversification and livestock management. We combined these data with remotely sensed information about vegetation growth and self-reported exposure to price fluctuations. Our statistical results showed that households experiencing lower ecological and economic variability, higher average levels of vegetation growth, and with greater levels of material wealth, were often those that undertook more actions to improve their conditions in the face of variability. The findings have implications both for how interventions aimed at supporting ongoing choices might be targeted and for theory construction related to social adaptation. PMID:24910710

  17. Responses to climate and economic risks and opportunities across national and ecological boundaries: changing household strategies on the Mongolian plateau.

    PubMed

    Brown, Daniel G; Agrawal, Arun; Sass, Daniel A; Wang, Jun; Hua, Jin; Xie, Yichun

    2013-01-01

    Climate changes on the Mongolian Plateau are creating new challenges for the households and communities of the region. Much of the existing research on household choices in response to climate variability and change focuses on environmental risks and stresses. In contrast, our analysis highlights the importance of taking into account environmental and economic opportunities in explaining household adaptation choices. We surveyed over 750 households arrayed along an ecological gradient and matched across the national border in Mongolia and the Inner Mongolia Autonomous Region, China, asking what changes in livelihoods strategies households made over the last ten years, and analyzed these choices in two broad categories of options: diversification and livestock management. We combined these data with remotely sensed information about vegetation growth and self-reported exposure to price fluctuations. Our statistical results showed that households experiencing lower ecological and economic variability, higher average levels of vegetation growth, and with greater levels of material wealth, were often those that undertook more actions to improve their conditions in the face of variability. The findings have implications both for how interventions aimed at supporting ongoing choices might be targeted and for theory construction related to social adaptation.

  18. Application of Concanavalin A during immune responsiveness skin-swelling tests facilitates measurement interpretation in mammalian ecology.

    PubMed

    Bílková, Barbora; Albrecht, Tomáš; Chudíčková, Milada; Holáň, Vladimír; Piálek, Jaroslav; Vinkler, Michal

    2016-07-01

    The skin-swelling test is a simple and widespread method used in field ecological research to estimate cellular immune responsiveness in animals. This immunoecological test is based on measuring the magnitude of tissue swelling response at specific times following subcutaneous application of an experimental pro-inflammatory stimulant. In the vast majority of studies across vertebrate taxa, phytohemagglutinin (PHA) is used as a universal stimulant. Given the complexity of immune response activation pathways of PHA, however, interpretation of test results can be ambiguous. Goal of this study was to improve methodology of the skin-swelling test to decrease this ambiguity. Here, we present an alternative protocol aimed at facilitating interpretation of skin-swelling data for mammals. Based on previous evidence suggesting that mammalian T cells are readily activated by Concanavalin A (ConA) in vitro, we compared cellular immune responses in vivo to PHA and ConA as an alternative pro-inflammatory stimulant in mice. We measured magnitude of tissue swelling and compared it with intensity of blood cell infiltration into tissue over a 72-hour interval. Our results corroborate that PHA and ConA show important differences in both dynamics and response amplitude in rodents. ConA induces stronger swelling with a distinct leukocyte activity pattern and higher pro-inflammatory cytokine (interleukin 6 [IL-6] and interferon gamma[IFN-γ]) expression than PHA during peak response (24-h post-treatment). Furthermore, unlike PHA, magnitude of swelling was positively associated with cellular activity (number of neutrophils infiltrating tissue) following ConA injection. We conclude that ConA is the more suitable stimulant for skin-swelling tests in mammals. This is because of the molecular binding specificity in the two lectins, that is, ConA specifically activates T cells while PHA also triggers erythroagglutination. We propose that ConA be used in all future ecological testing in

  19. The experimental investigation of bounce characteristics of ACV responsive skirt

    NASA Astrophysics Data System (ADS)

    Zhou, W. L.; Ma, T.

    This paper presents some experimental results on the bounce characteristics of the bag-finger responsive skirt and on skirt frequency response under cushion pressure excitation obtained in a large-scale box facility. The influence of some parameters on the amplitude and frequency of the skirt bounce motion and the amplitude of the cushion pressure oscillation were explored, and the corresponding bounce boundary curves are given. Some interesting nonlinear phenomena related to the skirt instability in the time domain response are presented. The mechanism for skirt bounce and the important parameters affecting skirt dynamic stability are examined, and some means for eliminating skirt bounce are introduced.

  20. Functional ecology of saltglands in shorebirds: Flexible responses to variable environmental conditions

    USGS Publications Warehouse

    Gutierrez, J.S.; Dietz, M.W.; Masero, J.A.; Gill, R.E.; Dekinga, Anne; Battley, Phil F.; Sanchez-Guzman, J. M.; Piersma, Theunis

    2012-01-01

    size of saltglands when demands are low suggests that any time costs of adjustment are lower than the costs of maintaining a larger size in this small but essential piece of metabolic machinery. ?? 2011 The Authors. Functional Ecology ?? 2011 British Ecological Society.

  1. FACTORS AFFECTING SENSITIVITY OF CHEMICAL AND ECOLOGICAL RESPONSES OF MARINE EMBAYMEMTS TO NITROGEN LOADING

    EPA Science Inventory

    This paper summarizes an ongoing examination of the primary factors that affect sensitivity of marine embayment responses to nitrogen loading. Included is a discussion of two methods for using these factors: classification of embayments into discrete sensitivity classes and norma...

  2. Transcriptome resources for the white-footed mouse (Peromyscus leucopus): new genomic tools for investigating ecologically divergent urban and rural populations

    PubMed Central

    Harris, Stephen E.; O’Neill, Rachel J.; Munshi-South, Jason

    2014-01-01

    Genomic resources are important and attainable for examining evolutionary change in divergent natural populations of non-model species. We utilized two Next Generation Sequencing (NGS) platforms, 454 and SOLiD 5500XL, to assemble low coverage transcriptomes of the white-footed mouse (Peromyscus leucopus), a widespread and abundant native rodent in eastern North America. We sequenced liver mRNA transcripts from multiple individuals collected from urban populations in New York City and rural populations in undisturbed protected areas nearby, and assembled a reference transcriptome using 1,080,065,954 SOLiD 5500XL (75 bp) reads and 3,052,640 454 GS FLX + reads. The reference contained 40,908 contigs with a N50 = 1,044 bp and a total content of 30.06 Megabases (Mb). Contigs were annotated from comparisons to Mus musculus (39.96% annotated) Uniprot databases. We identified 104,655 high quality single nucleotide polymorphisms (SNPs) and 65 single sequence repeats (SSRs) with flanking primers. We also used normalized read counts to identify putative gene expression differences in 10 genes between populations. There were 19 contigs significantly differentially expressed in urban populations compared to rural populations, with gene function annotations generally related to the translation and modification of proteins and those involved in immune responses. The individual transcriptomes generated in this study will be used to investigate evolutionary responses to urbanization. The reference transcriptome provides a valuable resource for the scientific community using North American Peromyscus species as emerging model systems for ecological genetics and adaptation. PMID:24980186

  3. [Ecology and ecologies].

    PubMed

    Valera, Luca

    2011-01-01

    Ecology (from the Greek words οιχοσ, "house" and λογια "study of") is the science of the "house", since it studies the environments where we live. There are three main ways of thinking about Ecology: Ecology as the study of interactions (between humans and the environment, between humans and living beings, between all living beings, etc.), Ecology as the statistical study of interactions, Ecology as a faith, or rather as a science that requires a metaphysical view. The history of Ecology shows us how this view was released by the label of "folk sense" to gain the epistemological status of science, a science that strives to be interdisciplinary. So, the aim of Ecology is to study, through a scientific methodology, the whole natural world, answering to very different questions, that arise from several fields (Economics, Biology, Sociology, Philosophy, etc.). The plurality of issues that Ecology has to face led, during the Twentieth-century, to branch off in several different "ecologies". As a result, each one of these new approaches chose as its own field a more limited and specific portion of reality.

  4. Placing prairie pothole wetlands along spatial and temporal continua to improve integration of wetland function in ecological investigations

    USGS Publications Warehouse

    Euliss, Ned H.; Mushet, David M.; Newton, Wesley E.; Otto, Clint R.V.; Nelson, Richard D.; LaBaugh, James W.; Scherff, Eric J.; Rosenberry, Donald O.

    2014-01-01

    We evaluated the efficacy of using chemical characteristics to rank wetland relation to surface and groundwater along a hydrologic continuum ranging from groundwater recharge to groundwater discharge. We used 27 years (1974–2002) of water chemistry data from 15 prairie pothole wetlands and known hydrologic connections of these wetlands to groundwater to evaluate spatial and temporal patterns in chemical characteristics that correspond to the unique ecosystem functions each wetland performed. Due to the mineral content and the low permeability rate of glacial till and soils, salinity of wetland waters increased along a continuum of wetland relation to groundwater recharge, flow-through or discharge. Mean inter-annual specific conductance (a proxy for salinity) increased along this continuum from wetlands that recharge groundwater being fresh to wetlands that receive groundwater discharge being the most saline, and wetlands that both recharge and discharge to groundwater (i.e., groundwater flow-through wetlands) being of intermediate salinity. The primary axis from a principal component analysis revealed that specific conductance (and major ions affecting conductance) explained 71% of the variation in wetland chemistry over the 27 years of this investigation. We found that long-term averages from this axis were useful to identify a wetland’s long-term relation to surface and groundwater. Yearly or seasonal measurements of specific conductance can be less definitive because of highly dynamic inter- and intra-annual climate cycles that affect water volumes and the interaction of groundwater and geologic materials, and thereby influence the chemical composition of wetland waters. The influence of wetland relation to surface and groundwater on water chemistry has application in many scientific disciplines and is especially needed to improve ecological understanding in wetland investigations. We suggest ways that monitoring in situ wetland conditions could be linked

  5. Placing prairie pothole wetlands along spatial and temporal continua to improve integration of wetland function in ecological investigations

    NASA Astrophysics Data System (ADS)

    Euliss, Ned H.; Mushet, David M.; Newton, Wesley E.; Otto, Clint R. V.; Nelson, Richard D.; LaBaugh, James W.; Scherff, Eric J.; Rosenberry, Donald O.

    2014-05-01

    We evaluated the efficacy of using chemical characteristics to rank wetland relation to surface and groundwater along a hydrologic continuum ranging from groundwater recharge to groundwater discharge. We used 27 years (1974-2002) of water chemistry data from 15 prairie pothole wetlands and known hydrologic connections of these wetlands to groundwater to evaluate spatial and temporal patterns in chemical characteristics that correspond to the unique ecosystem functions each wetland performed. Due to the mineral content and the low permeability rate of glacial till and soils, salinity of wetland waters increased along a continuum of wetland relation to groundwater recharge, flow-through or discharge. Mean inter-annual specific conductance (a proxy for salinity) increased along this continuum from wetlands that recharge groundwater being fresh to wetlands that receive groundwater discharge being the most saline, and wetlands that both recharge and discharge to groundwater (i.e., groundwater flow-through wetlands) being of intermediate salinity. The primary axis from a principal component analysis revealed that specific conductance (and major ions affecting conductance) explained 71% of the variation in wetland chemistry over the 27 years of this investigation. We found that long-term averages from this axis were useful to identify a wetland’s long-term relation to surface and groundwater. Yearly or seasonal measurements of specific conductance can be less definitive because of highly dynamic inter- and intra-annual climate cycles that affect water volumes and the interaction of groundwater and geologic materials, and thereby influence the chemical composition of wetland waters. The influence of wetland relation to surface and groundwater on water chemistry has application in many scientific disciplines and is especially needed to improve ecological understanding in wetland investigations. We suggest ways that monitoring in situ wetland conditions could be linked

  6. Experimental investigation of fuel cell dynamic response and control

    NASA Astrophysics Data System (ADS)

    Williams, Keith A.; Keith, Warren T.; Marcel, Michael J.; Haskew, Timothy A.; Shepard, W. Steve; Todd, Beth A.

    An experimental study of the dynamic response of a commercial fuel cell system is presented in this work. The primary goal of the research is an examination of the feasibility for using fuel cells in a load-following mode for vehicular applications, where load-following implies that the fuel cell system provides the power necessary for transient responses without the use of additional energy storage elements, such as batteries or super-capacitors. The dynamic response of fuel cell systems used in the load-following mode may have implications for safe and efficient operation of vehicles. To that end, a DC-DC converter was used to port the power output of the fuel cell to a resistive load using a pulse-width-modulating circuit. Frequency responses of the system were evaluated at a variety of DC offsets and AC amplitudes of the PWM duty cycle from 1 out to 400 Hz. Open-loop transient responses are then evaluated using transitions from 10% to 90% duty cycle levels, followed by dwells at the 90% level and then transitions back to the 10% level. A classical proportional-integral controller was then developed and used to close the loop around the system, with the result that the fuel cell system was driven to track the same transient. The controller was then used to drive the fuel cell system according to a reference power signal, which was a scaled-down copy of the simulated power output from an internal combustion engine powering a conventional automobile through the Federal Urban Driving Schedule (FUDS). The results showed that the fuel cell system is capable of tracking transient signals with sufficient fidelity such that it should be applicable for use in a load-following mode for vehicular applications. The results also highlight important issues that must be addressed in considering vehicular applications of fuel cells, such as the power conditioning circuit efficiency and the effect of stack heating on the system response.

  7. Salinity and Temperature Effects on Physiological Responses of Vibrio fischeri from Diverse Ecological Niches

    PubMed Central

    Soto, W.; Gutierrez, J.; Remmenga, M. D.; Nishiguchi, M. K.

    2009-01-01

    Vibrio fischeri is a bioluminescent bacterial symbiont of sepiolid squids (Cephalopoda: Sepiolidae) and monocentrid fishes (Actinopterygii: Monocentridae). V. fischeri exhibit competitive dominance within the allopatrically distributed squid genus Euprymna, which have led to the evolution of V. fischeri host specialists. In contrast, the host genus Sepiola contains sympatric species that is thought to have given rise to V. fischeri that have evolved as host generalists. Given that these ecological lifestyles may have a direct effect upon the growth spectrum and survival limits in contrasting environments, optimal growth ranges were obtained for numerous V. fischeri isolates from both free-living and host environments. Upper and lower limits of growth were observed in sodium chloride concentrations ranging from 0.0% to 9.0%. Sepiola symbiotic isolates possessed the least variation in growth throughout the entire salinity gradient, whereas isolates from Euprymna were the least uniform at <2.0% NaCl. V. fischeri fish symbionts (CG101 and MJ101) and all free-living strains were the most dissimilar at >5.0% NaCl. Growth kinetics of symbiotic V. fischeri strains were also measured under a range of salinity and temperature combinations. Symbiotic V. fischeri ES114 and ET101 exhibited a synergistic effect for salinity and temperature, where significant differences in growth rates due to salinity existed only at low temperatures. Thus, abiotic factors such as temperature and salinity have differential effects between free-living and symbiotic strains of V. fischeri, which may alter colonization efficiency prior to infection. PMID:18587609

  8. Hydro-ecologic responses to land use in small urbanizing watersheds within the Chesapeake Bay watershed

    NASA Astrophysics Data System (ADS)

    Moglen, Glenn E.; Nelson, Kären C.; Palmer, Margaret A.; Pizzuto, James E.; Rogers, Catriona E.; Hejazi, Mohamad I.

    Urbanization in the Chesapeake Bay watershed is having dramatic impacts on the streams and rivers that feed the Bay. Increasing imperviousness has led to higher peak flows and lower base flows. The movement of pollutants and other materials to receiving waters has increased and stream water temperatures have risen. These changes alter the structure and functioning of rivers, streams, and associated riparian corridors and result in changes in ecosystem services. We define a hydrologic disturbance index that indicates varying degrees of disturbance on a reach-by-reach basis, dependent on the aggregate amount of urbanization upstream of each reach. For current conditions this index is more variable than for future conditions, because current land use in the study watershed is more variable, containing mixtures of urban, agricultural, and forested land. In contrast, future land use is projected to be more uniformly urban, leading to a less variable but greater overall degree of hydrologic disturbance. Two effects of urbanization on fish are explored through ecological modeling: effects of streambed disturbance on food availability and effects of stream temperature on spawning. We tabulate food availability as a function of bed-mobility for 30 different fish species. We show that additional stress occurs with additional urbanization of the watershed. We show that the urban-related increase in stream temperatures may cause several warm-water species to actually gain opportunities to spawn in some cases. However, combining food availability and spawning day availability into a single index reveals highly stressful conditions for all fish species under the fully developed scenario.

  9. Streamflow Responses and Ecological Implications of Climate Change in New York City Water Supply Watershed

    NASA Astrophysics Data System (ADS)

    Pradhanang, S. M.; Mukundan, R.; Schneiderman, E.; Zion, M. S.; Swamy, A.; Pierson, D. C.; Frei, A.; Easton, Z. M.; Fuka, D. R.; Steenhuis, T. S.

    2011-12-01

    The impact of climate change in the North East United States is already observed in the form of shorter winter, higher annual average temperature, and more frequent extreme heat and precipitation events. These changes could have profound effects on the New York City (NYC) Water Supply and ecological integrity of the watersheds; and the implications of such changes are not well understood. The objective of this study is to examine how future changes in precipitation and air temperature may translate into changes in streamflow in the NYC Water Supply watershed using the Soil and Water Assessment Tool-Water Balance (SWAT-WB). A comparative analysis between simulated streamflow for baseline period (1964-2008) and future scenarios (2081-2100) was carried out for streamflow indicators that are important for understanding how river flow dynamics will impact the water supply, aquatic health, and physical structures in the stream corridor. We analyze the impacts of changes in the magnitude, timing, duration, frequency, and rate of hydrologic events using the Indicators of Hydrologic Alteration (IHA) tool. Our results indicate that warming during the winter and the early spring diminishes snowpack and influence timing of snowmelt. The winter and spring streamflow are projected to increase but summer will be drier in future. Decreased flow during April and summer months will influence timing of fish spawning and their habitats. Low flows, hydrograph pulses, rise and fall rates are expected to increase due to climate change, potentially creating unfavorable conditions for native species and aquatic invertebrates inhabiting along river's edge, and affecting stream bank stability and physical structures.

  10. Ecological traits affect the response of tropical forest bird species to land-use intensity.

    PubMed

    Newbold, Tim; Scharlemann, Jörn P W; Butchart, Stuart H M; Sekercioğlu, Cağan H; Alkemade, Rob; Booth, Hollie; Purves, Drew W

    2013-01-01

    Land-use change is one of the main drivers of current and likely future biodiversity loss. Therefore, understanding how species are affected by it is crucial to guide conservation decisions. Species respond differently to land-use change, possibly related to their traits. Using pan-tropical data on bird occurrence and abundance across a human land-use intensity gradient, we tested the effects of seven traits on observed responses. A likelihood-based approach allowed us to quantify uncertainty in modelled responses, essential for applying the model to project future change. Compared with undisturbed habitats, the average probability of occurrence of bird species was 7.8 per cent and 31.4 per cent lower, and abundance declined by 3.7 per cent and 19.2 per cent in habitats with low and high human land-use intensity, respectively. Five of the seven traits tested affected the observed responses significantly: long-lived, large, non-migratory, primarily frugivorous or insectivorous forest specialists were both less likely to occur and less abundant in more intensively used habitats than short-lived, small, migratory, non-frugivorous/insectivorous habitat generalists. The finding that species responses to land use depend on their traits is important for understanding ecosystem functioning, because species' traits determine their contribution to ecosystem processes. Furthermore, the loss of species with particular traits might have implications for the delivery of ecosystem services.

  11. EUTROPHICATION OF COASTAL WATER BODIES: RELATIONSHIPS BETWEEN NUTRIENT LOADINGS AND ECOLOGICAL RESPONSE

    EPA Science Inventory

    This newly initiated research is intended to provide environmental managers with an empirical method to develop regional nutrient input limits for East Coast estuaries and other coastal water bodies. Our goal is to create an improved model of nutrient load-response relationships....

  12. EUTROPHICATION OF COASTAL WATER BODIES: RELATIONSHIPS BETWEEN NUTRIENT LOADING AND ECOLOGICAL RESPONSE

    EPA Science Inventory

    This newly initiated research will provide environmental managers with an empirical method to develop regional nutrient input limits for East Coast estuaries/coastal water bodies. The goal will be to reduce the current uncertainty associated with nutrient load-response relationsh...

  13. Adaptive Patterns of Stress Responsivity: A Preliminary Investigation

    ERIC Educational Resources Information Center

    Del Giudice, Marco; Hinnant, J. Benjamin; Ellis, Bruce J.; El-Sheikh, Mona

    2012-01-01

    The adaptive calibration model (ACM) is an evolutionary-developmental theory of individual differences in stress responsivity. In this article, we tested some key predictions of the ACM in a middle childhood sample (N = 256). Measures of autonomic nervous system activity across the sympathetic and parasympathetic branches validated the 4-pattern…

  14. An Exploratory Investigation into the Nature of Literary Response.

    ERIC Educational Resources Information Center

    Zaharias, Jane Ann

    A study was conducted (1) to examine the effects of the same reading materials on different individuals and the effects of different reading materials on the same person and (2) to explore whether an individual's preferred pattern of response to a literary selection was related to differences in sex, reading ability, and learning style. Subjects…

  15. 21 CFR 812.110 - Specific responsibilities of investigators.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... other applicable FDA regulations, and any conditions of approval imposed by an IRB or FDA. (c... participate before obtaining IRB and FDA approval. (b) Compliance. An investigator shall conduct...

  16. 21 CFR 812.110 - Specific responsibilities of investigators.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... other applicable FDA regulations, and any conditions of approval imposed by an IRB or FDA. (c... participate before obtaining IRB and FDA approval. (b) Compliance. An investigator shall conduct...

  17. 21 CFR 812.110 - Specific responsibilities of investigators.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... other applicable FDA regulations, and any conditions of approval imposed by an IRB or FDA. (c... participate before obtaining IRB and FDA approval. (b) Compliance. An investigator shall conduct...

  18. 21 CFR 812.110 - Specific responsibilities of investigators.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... other applicable FDA regulations, and any conditions of approval imposed by an IRB or FDA. (c... participate before obtaining IRB and FDA approval. (b) Compliance. An investigator shall conduct...

  19. 21 CFR 812.110 - Specific responsibilities of investigators.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... other applicable FDA regulations, and any conditions of approval imposed by an IRB or FDA. (c... participate before obtaining IRB and FDA approval. (b) Compliance. An investigator shall conduct...

  20. An Investigation into the Prevalence of Ecological Misconceptions in Upper Secondary Students and Implications for Pre-Service Teacher Education

    ERIC Educational Resources Information Center

    Butler, J.; Mooney Simmie, G.; O'Grady, A.

    2015-01-01

    Students' and teachers' misconceptions are an international concern among researchers in science education; they influence how students learn and teachers' teach knowledge and are a hindrance in the acquisition of accurate knowledge. This paper reports on a literature synthesis of existing research about ecological misconceptions. One means of…

  1. Room response analyses to investigate waste disposal issues

    SciTech Connect

    Arguello, J.G.; Weatherby, J.R.; Stone, C.M.; Morgan, H.S.; Wawersik, W.R.

    1991-01-01

    The long-term structural behavior of WIPP disposal rooms under various hypothetical repository conditions has been studied at Sandia National Laboratories for the past few years. This paper presents an overview of structural analyses that address issues dealing with the condition of the room and its contents. The analyses represent a progression in the development of a model for disposal room response that has encountered and overcome many computational challenges along the way. 13 refs., 8 figs.

  2. The response of relatives to medicolegal investigations and forensic autopsy.

    PubMed

    Plattner, Thomas; Scheurer, Eva; Zollinger, Ulrich

    2002-12-01

    Relatives of deceased persons, on whose body a forensic autopsy had been performed at the Institute of Forensic Science, Bern, Switzerland, were interrogated by a questionnaire. The aim was to investigate the attitude of relatives toward medicolegal investigation procedures in general and toward forensic autopsy in particular. A great majority of the relatives showed a positive or indifferent attitude toward a forensic autopsy. They showed a great interest in autopsy results and wished to be informed. It was concluded that information given before the autopsy is important for better understanding and can, if properly given, improve the relatives' acceptance and collaboration regarding forensic investigations. By contrast, a lack of information before the autopsy and about the autopsy results can cause further suffering on behalf of the bereaved. A forensic autopsy can be of great benefit for relatives and can help them to cope with a tragic loss.

  3. Ecology, Microbial

    SciTech Connect

    Konopka, Allan

    2009-05-15

    Microbial ecology is a relatively young discipline within the field of microbiology. Its modern history spans just the past 60 years, and the field is defined by its emphasis on understanding the interactions of microbes with their environment, rather than their behavior under artificial laboratory conditions. Because microbes are ubiquitous, microbial ecologists study a broad diversity of habitats that range from aquatic to terrestrial to plant- or animal-associated. This has made it a challenge to identify unifying principles within the field. One approach is to recognize that although the activity of microbes in nature have effects at the macroscale, they interact with their physical, chemical and biological milieu at a scale of micrometers. At this scale, several different microbial ecosystems can be defined, based upon association with particles, the presence of environmental gradients and the continuous availability of water. Principles applicable to microbial ecology reflect not only their population ecology and physiological ecology, but also their broad versatility and quantitative importance in the biosphere as biogeochemical catalysts and capacity for rapid physiological and evolutionary responses.

  4. Ecology, Microbial

    SciTech Connect

    Konopka, Allan

    2009-03-19

    Microbial ecology is a relatively young discipline within the field of microbiology. Its modern history spans just the past 60 years, and the field is defined by its emphasis on understanding the interactions of microbes with their environment, rather than their behavior under artificial laboratory conditions. Because microbes are ubiquitous, microbial ecologists study a broad diversity of habitats that range from aquatic to terrestrial to plant- or animal-associated. This has made it a challenge to identify unifying principles within the field. One approach is to recognize that although the activity of microbes in nature have effects at the macroscale, they interact with their physical, chemical and biological milieu at a scale of micrometers. At this scale, several different microbial ecosystems can be defined, based upon association with particles, the presence of environmental gradients and the continuous availability of water. Principles applicable to microbial ecology reflect not only their population ecology and physiological ecology, but also their broad versatility and quantitative importance in the biosphere as biogeochemical catalysts and capacity for rapid physiological and evolutionary responses.

  5. White University Students' Responses to Societal Racism: A Qualitative Investigation

    ERIC Educational Resources Information Center

    Spanierman, Lisa A.; Oh, Euna; Poteat, V. Paul; Hund, Anita R.; McClair, Vetisha L.; Beer, Amanda M.; Clarke, Alexis M.

    2008-01-01

    The purpose of this investigation was to extend earlier conceptual and empirical literature on the ways in which White individuals respond to societal racism. To this end, the authors conducted in-depth interviews to examine 11 midwestern, non-Hispanic, White university students' reactions and experiences related to individual and institutional…

  6. The ecological response of Carex lasiocarpa community in the Riparian Wetlands to the environmental gradient of water depth in Sanjiang Plain, Northeast China.

    PubMed

    Luan, Zhaoqing; Wang, Zhongxin; Yan, Dandan; Liu, Guihua; Xu, Yingying

    2013-01-01

    The response of Carex lasiocarpa in riparian wetlands in Sanjiang Plain to the environmental gradient of water depth was analyzed by using the Gaussian Model based on the biomass and average height data, and the ecological water-depth amplitude of Carex lasiocarpa was derived. The results indicated that the optimum ecological water-depth amplitude of Carex lasiocarpa based on biomass was [13.45 cm, 29.78 cm], while the optimum ecological water-depth amplitude of Carex lasiocarpa based on average height was [2.31 cm, 40.11 cm]. The intersection of the ecological water-depth amplitudes based on biomass and height confirmed that the optimum ecological water-depth amplitude of Carex lasiocarpa was [13.45 cm, 29.78 cm] and the optimist growing water-depth of Carex lasiocarpa was 21.4 cm. The TWINSPAN, a polythetic and divisive classification tool, was used to classify the wetland ecological series into 6 associations. Result of TWINSPAN matrix classification reflected an obvious environmental gradient in these associations: water-depth gradient. The relation of biodiversity of Carex lasiocarpa community and water depth was determined by calculating the diversity index of each association.

  7. Lifestyle and Ice: The Relationship between Ecological Specialization and Response to Pleistocene Climate Change.

    PubMed

    Kašparová, Eva; Van de Putte, Anton P; Marshall, Craig; Janko, Karel

    2015-01-01

    Major climatic changes in the Pleistocene had significant effects on marine organisms and the environments in which they lived. The presence of divergent patterns of demographic history even among phylogenetically closely-related species sharing climatic changes raises questions as to the respective influence of species-specific traits on population structure. In this work we tested whether the lifestyle of Antarctic notothenioid benthic and pelagic fish species from the Southern Ocean influenced the concerted population response to Pleistocene climatic fluctuations. This was done by a comparative analysis of sequence variation at the cyt b and S7 loci in nine newly sequenced and four re-analysed species. We found that all species underwent more or less intensive changes in population size but we also found consistent differences between demographic histories of pelagic and benthic species. Contemporary pelagic populations are significantly more genetically diverse and bear traces of older demographic expansions than less diverse benthic species that show evidence of more recent population expansions. Our findings suggest that the lifestyles of different species have strong influences on their responses to the same environmental events. Our data, in conjunction with previous studies showing a constant diversification tempo of these species during the Pleistocene, support the hypothesis that Pleistocene glaciations had a smaller effect on pelagic species than on benthic species whose survival may have relied upon ephemeral refugia in shallow shelf waters. These findings suggest that the interaction between lifestyle and environmental changes should be considered in genetic analyses. PMID:26535569

  8. Ecological Framework For Assessing Changes In Soil Water And Carbon In Response To Degrading Permafrost

    NASA Astrophysics Data System (ADS)

    Jorgenson, T.

    2011-12-01

    The response of soil water and carbon to permafrost degradation differs greatly across the varied terrain of boreal Alaska. Responses can be broadly partitioned among rocky uplands on ice poor bedrock and colluvial deposits, loamy uplands on extremely ice rich Pleistocene loess, sandy lowlands on sand sheets, and peaty lowlands on abandoned floodplains, retransported deposits on lower slopes, and lowland loess. On rocky uplands, soil carbon and water stocks are low and most carbon and water is lost after fire and subsequent thawing of permafrost. On loamy uplands, much of the soil carbon is lost after fire, but soils remain saturated after thawing of the ice rich intermediate layer. Deeper permafrost is resilient. On sandy lowlands, forest soils have low carbon stocks and water contents, in contrast to the high carbon stocks in perched lakes maintained by permafrost. Thawing of permafrost leads to drying of forest soils and draining of lakes, exposing soil carbon to aerobic conditions for decomposition. Peaty lowlands have thick peat deposits associated with black spruce permafrost plateaus and unfrozen collapse-scar bogs and fens. Thawing leads to 2 to 4 m of collapse and large loss of ice.Formation of bogs impounds water in depressions and leads to rapid accumulation of bog peat. Thawing of forest peat also leads to substantial decomposition of old forest peat.

  9. Lifestyle and Ice: The Relationship between Ecological Specialization and Response to Pleistocene Climate Change

    PubMed Central

    Kašparová, Eva; Van de Putte, Anton P.; Marshall, Craig; Janko, Karel

    2015-01-01

    Major climatic changes in the Pleistocene had significant effects on marine organisms and the environments in which they lived. The presence of divergent patterns of demographic history even among phylogenetically closely-related species sharing climatic changes raises questions as to the respective influence of species-specific traits on population structure. In this work we tested whether the lifestyle of Antarctic notothenioid benthic and pelagic fish species from the Southern Ocean influenced the concerted population response to Pleistocene climatic fluctuations. This was done by a comparative analysis of sequence variation at the cyt b and S7 loci in nine newly sequenced and four re-analysed species. We found that all species underwent more or less intensive changes in population size but we also found consistent differences between demographic histories of pelagic and benthic species. Contemporary pelagic populations are significantly more genetically diverse and bear traces of older demographic expansions than less diverse benthic species that show evidence of more recent population expansions. Our findings suggest that the lifestyles of different species have strong influences on their responses to the same environmental events. Our data, in conjunction with previous studies showing a constant diversification tempo of these species during the Pleistocene, support the hypothesis that Pleistocene glaciations had a smaller effect on pelagic species than on benthic species whose survival may have relied upon ephemeral refugia in shallow shelf waters. These findings suggest that the interaction between lifestyle and environmental changes should be considered in genetic analyses. PMID:26535569

  10. Invader partitions ecological and evolutionary responses to above- and belowground herbivory.

    PubMed

    Huang, Wei; Carrillo, Juli; Ding, Jianqing; Siemann, Evan

    2012-11-01

    Interactions between above- and belowground herbivory may, affect plant performance and structure communities. Though many studies have documented interactions of invasive plants and.herbivores, none shows how above- and belowground herbivores interact to affect invasive plant performance. Here, in a common garden in China, we subjected genetically differentiated tallow trees (Triadica sebifera) from native (China) and invaded (United States) ranges to herbivory by aboveground adults and belowground larvae of a specialist beetle, Bikasha collaris. Overall, relative to plants from China, U.S. plants had greater total and aboveground mass, comparable belowground mass, lower resistance to both above- and belowground herbivory, and higher tolerance to aboveground herbivory only. Accordingly, aboveground adults had greater impacts on Chinese plants, but belowground larvae more strongly impacted U.S. plants. These results indicate that the invader may adopt an "aboveground first" strategy, allocating more resources aboveground in response to selection for increased competitive ability, which increases aboveground tolerance to herbivory. Furthermore, we found that adults facilitated larval success, and these feedbacks were stronger for U.S. plants, suggesting that aboveground feeding of adults may be associated with lower defenses and/or higher resources belowground in the invader. Therefore, plants may have evolved different responses to above- and belowground herbivory, which can affect invasion success and herbivore population dynamics. These findings may provide new insights for an effective biological control program against invasive plants.

  11. Lifestyle and Ice: The Relationship between Ecological Specialization and Response to Pleistocene Climate Change.

    PubMed

    Kašparová, Eva; Van de Putte, Anton P; Marshall, Craig; Janko, Karel

    2015-01-01

    Major climatic changes in the Pleistocene had significant effects on marine organisms and the environments in which they lived. The presence of divergent patterns of demographic history even among phylogenetically closely-related species sharing climatic changes raises questions as to the respective influence of species-specific traits on population structure. In this work we tested whether the lifestyle of Antarctic notothenioid benthic and pelagic fish species from the Southern Ocean influenced the concerted population response to Pleistocene climatic fluctuations. This was done by a comparative analysis of sequence variation at the cyt b and S7 loci in nine newly sequenced and four re-analysed species. We found that all species underwent more or less intensive changes in population size but we also found consistent differences between demographic histories of pelagic and benthic species. Contemporary pelagic populations are significantly more genetically diverse and bear traces of older demographic expansions than less diverse benthic species that show evidence of more recent population expansions. Our findings suggest that the lifestyles of different species have strong influences on their responses to the same environmental events. Our data, in conjunction with previous studies showing a constant diversification tempo of these species during the Pleistocene, support the hypothesis that Pleistocene glaciations had a smaller effect on pelagic species than on benthic species whose survival may have relied upon ephemeral refugia in shallow shelf waters. These findings suggest that the interaction between lifestyle and environmental changes should be considered in genetic analyses.

  12. Models and Methods to Investigate Acute Stress Responses in Cattle

    PubMed Central

    Chen, Yi; Arsenault, Ryan; Napper, Scott; Griebel, Philip

    2015-01-01

    There is a growing appreciation within the livestock industry and throughout society that animal stress is an important issue that must be addressed. With implications for animal health, well-being, and productivity, minimizing animal stress through improved animal management procedures and/or selective breeding is becoming a priority. Effective management of stress, however, depends on the ability to identify and quantify the effects of various stressors and determine if individual or combined stressors have distinct biological effects. Furthermore, it is critical to determine the duration of stress-induced biological effects if we are to understand how stress alters animal production and disease susceptibility. Common stress models used to evaluate both psychological and physical stressors in cattle are reviewed. We identify some of the major gaps in our knowledge regarding responses to specific stressors and propose more integrated methodologies and approaches to measuring these responses. These approaches are based on an increased knowledge of both the metabolic and immune effects of stress. Finally, we speculate on how these findings may impact animal agriculture, as well as the potential application of large animal models to understanding human stress. PMID:26633525

  13. Models and Methods to Investigate Acute Stress Responses in Cattle.

    PubMed

    Chen, Yi; Arsenault, Ryan; Napper, Scott; Griebel, Philip

    2015-01-01

    There is a growing appreciation within the livestock industry and throughout society that animal stress is an important issue that must be addressed. With implications for animal health, well-being, and productivity, minimizing animal stress through improved animal management procedures and/or selective breeding is becoming a priority. Effective management of stress, however, depends on the ability to identify and quantify the effects of various stressors and determine if individual or combined stressors have distinct biological effects. Furthermore, it is critical to determine the duration of stress-induced biological effects if we are to understand how stress alters animal production and disease susceptibility. Common stress models used to evaluate both psychological and physical stressors in cattle are reviewed. We identify some of the major gaps in our knowledge regarding responses to specific stressors and propose more integrated methodologies and approaches to measuring these responses. These approaches are based on an increased knowledge of both the metabolic and immune effects of stress. Finally, we speculate on how these findings may impact animal agriculture, as well as the potential application of large animal models to understanding human stress. PMID:26633525

  14. "Yo Soy Indígena": Identifying and Using Traditional Ecological Knowledge (TEK) to Make the Teaching of Science Culturally Responsive for Maya Girls

    ERIC Educational Resources Information Center

    Hamlin, Maria L.

    2013-01-01

    This study examines how traditional ecological knowledge--TEK--can be identified and utilized to create culturally responsive science learning opportunities for Maya girls from a community in the Guatemalan highlands. Maya girls are situated in a complex socio-historical and political context rooted in racism and sexism. This study contextualizes…

  15. Ecological controls on water-cycle response to climate variability in deserts

    PubMed Central

    Scanlon, B. R.; Levitt, D. G.; Reedy, R. C.; Keese, K. E.; Sully, M. J.

    2005-01-01

    The impact of climate variability on the water cycle in desert ecosystems is controlled by biospheric feedback at interannual to millennial timescales. This paper describes a unique field dataset from weighing lysimeters beneath nonvegetated and vegetated systems that unequivocally demonstrates the role of vegetation dynamics in controlling water cycle response to interannual climate variability related to El Niño southern oscillation in the Mojave Desert. Extreme El Niño winter precipitation (2.3-2.5 times normal) typical of the U.S. Southwest would be expected to increase groundwater recharge, which is critical for water resources in semiarid and arid regions. However, lysimeter data indicate that rapid increases in vegetation productivity in response to elevated winter precipitation reduced soil water storage to half of that in a nonvegetated lysimeter, thereby precluding deep drainage below the root zone that would otherwise result in groundwater recharge. Vegetation dynamics have been controlling the water cycle in interdrainage desert areas throughout the U.S. Southwest, maintaining dry soil conditions and upward soil water flow since the last glacial period (10,000-15,000 yr ago), as shown by soil water chloride accumulations. Although measurements are specific to the U.S. Southwest, correlations between satellite-based vegetation productivity and elevated precipitation related to El Niño southern oscillation indicate this model may be applicable to desert basins globally. Understanding the two-way coupling between vegetation dynamics and the water cycle is critical for predicting how climate variability influences hydrology and water resources in water-limited landscapes. PMID:15837922

  16. Ecological controls on water-cycle response to climate variability in deserts.

    PubMed

    Scanlon, B R; Levitt, D G; Reedy, R C; Keese, K E; Sully, M J

    2005-04-26

    The impact of climate variability on the water cycle in desert ecosystems is controlled by biospheric feedback at interannual to millennial timescales. This paper describes a unique field dataset from weighing lysimeters beneath nonvegetated and vegetated systems that unequivocally demonstrates the role of vegetation dynamics in controlling water cycle response to interannual climate variability related to El Nino southern oscillation in the Mojave Desert. Extreme El Nino winter precipitation (2.3-2.5 times normal) typical of the U.S. Southwest would be expected to increase groundwater recharge, which is critical for water resources in semiarid and arid regions. However, lysimeter data indicate that rapid increases in vegetation productivity in response to elevated winter precipitation reduced soil water storage to half of that in a nonvegetated lysimeter, thereby precluding deep drainage below the root zone that would otherwise result in groundwater recharge. Vegetation dynamics have been controlling the water cycle in interdrainage desert areas throughout the U.S. Southwest, maintaining dry soil conditions and upward soil water flow since the last glacial period (10,000-15,000 yr ago), as shown by soil water chloride accumulations. Although measurements are specific to the U.S. Southwest, correlations between satellite-based vegetation productivity and elevated precipitation related to El Nino southern oscillation indicate this model may be applicable to desert basins globally. Understanding the two-way coupling between vegetation dynamics and the water cycle is critical for predicting how climate variability influences hydrology and water resources in water-limited landscapes. PMID:15837922

  17. Dependence of the results of ecological-epidemic investigation of influenza A(H1N1) on immunity

    NASA Astrophysics Data System (ADS)

    Fathudinova, Mohinav; Alimova, Barno; Rahimova, Halima

    2016-07-01

    This report presents the results of ecology-epidemical and immunological researches influ-enza virus A (H1 N1) and acute respiratory infection in Dushanbe from 2011 till 2015. The received results epidemiological and immunological analysis showed us, that last years has been changed not only characteristics of influenza epidemic, but it can not be notice the low-er of intensively of the collective immunity to actual versions influenza viruses A and B

  18. An investigation of the facsimile camera response to object motion

    NASA Technical Reports Server (NTRS)

    Huck, F. O.; Wall, S. D.; Burcher, E. E.

    1974-01-01

    A general analytical model of the facsimile camera response to object motion is derived as an initial step toward characterizing the resulting image degradation. This model expresses the spatial convolution of a time-varying object radiance distribution and camera point-spread function for each picture element in the image. Time variations and these two functions during each convolution account for blurring of small image detail, and variations between, as well as during, successive convolutions account for geometric image distortions. If the object moves beyond the angular extent of several picture elements while it is being imaged, then geometric distortion tends to dominate blurring as the primary cause of image degradation. The extent of distortion depends not only on object size and velocity but also on the direction of object motion, and is therefore difficult to classify in a general sense.

  19. Investigation of rice proteomic change in response to microgravity

    NASA Astrophysics Data System (ADS)

    Sun, Weining

    Gravity is one of the environmental factors that control development and growth of plants. Plant cells which are not part of specialized tissues such as the root columella can also sense gravity. Space environment, such as space shuttle missions, space labortories and space stations, etc. provide unique oppotunities to study the microgravity response of plant. During the Shenzhou 8 mission in November 2011, we cultured rice cali on the spaceship and the samples were fixed 4 days after launch. The flying samples in the static position (micro g, mug) and in the centrifuge which provide 1 g force to mimic the 1 g gravity in space, were recovered and the proteome changes were analyzed by iTRAQ. In total, 4840 proteins were identified, including 2085 proteins with function annotation by GO analysis. 431 proteins were changed >1.5 fold in space µg /ground group, including 179 up-regulated proteins and down-regulated 252 proteins. 321 proteins were changed >1.5 fold in space muµg / space 1 g group, among which 205 proteins were the same differentially expressed proteins responsive to microgravity. Enrichment of the differnetially expressed proteins by GO analysis showed that the ARF GTPase activity regulation proteins were enriched when compared the space µg with space 1 g sample, whereas the nucleic acid binding and DNA damage repairing proteins were enriched when compared the space µg and ground sample. Microscopic comparison of the rice cali showed that the space grown cells are more uniformed in size and proliferation, suggesting that cell proliferation pattern was changed in space microgravity conditions.

  20. New Modeling Approaches to Investigate Cell Signaling in Radiation Response

    NASA Technical Reports Server (NTRS)

    Plante, Ianik; Cucinotta, Francis A.; Ponomarev, Artem L.

    2011-01-01

    Ionizing radiation damages individual cells and tissues leading to harmful biological effects. Among many radiation-induced lesions, DNA double-strand breaks (DSB) are considered the key precursors of most early and late effects [1] leading to direct mutation or aberrant signal transduction processes. In response to damage, a flow of information is communicated to cells not directly hit by the radiation through signal transduction pathways [2]. Non-targeted effects (NTE), which includes bystander effects and genomic instability in the progeny of irradiated cells and tissues, may be particularly important for space radiation risk assessment [1], because astronauts are exposed to a low fluence of heavy ions and only a small fraction of cells are traversed by an ion. NTE may also have important consequences clinical radiotherapy [3]. In the recent years, new simulation tools and modeling approaches have become available to study the tissue response to radiation. The simulation of signal transduction pathways require many elements such as detailed track structure calculations, a tissue or cell culture model, knowledge of biochemical pathways and Brownian Dynamics (BD) propagators of the signaling molecules in their micro-environment. Recently, the Monte-Carlo simulation code of radiation track structure RITRACKS was used for micro and nano-dosimetry calculations [4]. RITRACKS will be used to calculate the fraction of cells traversed by an ion and delta-rays and the energy deposited in cells in a tissue model. RITRACKS also simulates the formation of chemical species by the radiolysis of water [5], notably the .OH radical. This molecule is implicated in DNA damage and in the activation of the transforming growth factor beta (TGF), a signaling molecule involved in NTE. BD algorithms for a particle near a membrane comprising receptors were also developed and will be used to simulate trajectories of signaling molecules in the micro-environment and characterize autocrine

  1. 14 CFR 431.45 - Mishap investigation plan and emergency response plan.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Mishap investigation plan and emergency... Mishap investigation plan and emergency response plan. (a) Mishap investigation plan and emergency... shall also submit an emergency response plan (ERP) that contains procedures for informing the...

  2. After the disaster: the hydrogeomorphic, ecological, and biological responses to the 1980 eruption of Mount St. Helens, Washington

    USGS Publications Warehouse

    Major, Jon J.; Crisafulli, Charlie; Bishop, John

    2009-01-01

    The 1980 eruption of Mount St. Helens caused instantaneous landscape disturbance on a grand scale. On 18 May 1980, an ensemble of volcanic processes, including a debris avalanche, a directed pyroclastic density current, voluminous lahars, and widespread tephra fall, abruptly altered landscape hydrology and geomorphology, and created distinctive disturbance zones having varying impacts on regional biota. Response to the geological and ecological disturbances has been varied and complex. In general, eruption-induced alterations in landscape hydrology and geomorphology led to enhanced stormflow discharge and sediment transport. Although the hydrological response to landscape perturbation has diminished, enhanced sediment transport persists in some basins. In the nearly 30 years since the eruption, 350 million (metric) tons of suspended sediment has been delivered from the Toutle River watershed to the Cowlitz River (roughly 40 times the average annual preeruption suspended-sediment discharge of the Columbia River). Such prodigious sediment loading has wreaked considerable socioeconomic havoc, causing significant channel aggradation and loss of flood conveyance capacity. Significant and ongoing engineering efforts have been required to mitigate these problems. The overall biological evolution of the eruption-impacted landscape can be viewed in terms of a framework of survivor legacies. Despite appearances to the contrary, a surprising number of species survived the eruption, even in the most heavily devastated areas. With time, survivor “hotspots” have coalesced into larger patches, and have served as stepping stones for immigrant colonization. The importance of biological legacies will diminish with time, but the intertwined trajectories of geophysical and biological successions will influence the geological and biological responses to the 1980 eruption for decades to come.

  3. Ecological Response to Extreme Flow Events in Streams and Rivers: Implications of Climate Change for Aquatic Biodiversity

    NASA Astrophysics Data System (ADS)

    Hawkins, C. P.; Vander Laan, J. J.; Dhungel, S.; Tarboton, D. G.

    2014-12-01

    We used the USEPA's 2008-2009 National Rivers and Streams Assessment (NRSA) data to assess the potential sensitivity of stream biodiversity to both spatial variation in measures of extreme flow and likely changes in extreme flows associated with projected climate change. The NRSA data consisted of macroinvertebrate samples collected at 1313 reference-quality sites. We characterized the hydrologic regimes at each of these sites by developing Random Forest empirical models from long-term (≥ 20 years) daily flow records obtained from 601 gaged USGS stations. These models described spatial variation in 16 flow variables as a function of climate and watershed attributes. Three of the models characterized aspects of extreme flow: the mean number of zero-flow events per year (ZeroDays), the mean number of high-flow events per year (HighDays = number of events per year that exceed the 95th percentile of mean annual flow), and the coefficient of variation of daily flows (CV). We used these models to predict the flow attributes expected at each of the 1313 sites with ecological data. We then built additional Random Forest models that related among-site differences in stream macroinvertebrate taxonomic composition, assemblage richness, and the likelihood of observing individual taxa to the 16 measures of flow regime and other environmental predictors. At the national level, ZeroDays was an important predictor of macroinvertebrate biodiversity: richness declined as ZeroDays increased. A similar pattern was observed when analyses were restricted to lowland and plains streams. For eastern highland streams, HighDays was a better predictor of stream biodiversity than aspects of low flow: richness declined as HighDays increased. For western streams, CV was a better predictor of biodiversity than either ZeroDays or HighDays: biodiversity decreased as CV increased. Empirical models that linked flow attributes to climate change projections imply that flow regime response to climate

  4. Forest response to CO{sub 2} enrichment: Physiology and ecology of loblolly pine

    SciTech Connect

    Strain, B.R.; Thomas, R.B.

    1997-03-10

    This report covers the results of a long-term project with the primary objective of developing and testing hypotheses on the environmental and physiological controls of loblolly pine response to atmospheric CO{sub 2} enrichment. Earlier research under DOE funding had provided information from loblolly pine and other plant species which allowed the development of specific hypotheses. Phase 1 of this research was a two year pot study of loblolly seedlings to determine the interaction of CO{sub 2} enrichment with soil nutrition. Phase 2 began with the enrichment of loblolly seedlings being grown in the ground, rather than pots, and continued through December 1995. Phase 3 began in April 1994 with the enrichment of undisturbed Piedmont North Carolina old field undergoing succession, including herbaceous annual plants, perennial grasses, and loblolly pine tree seedlings. Phase 3 was designed to gather preliminary information on a regenerating loblolly forest to be used for the development of hypotheses and measurement techniques for a long-term Free Air CO{sub 2} Enrichment (FACE) study of regenerating forest in Duke Forest.

  5. Ecology of Indigenous Soil Rhizobia: Response of Bradyrhizobium japonicum to Readily Available Substrates †

    PubMed Central

    Viteri, Silvio E.; Schmidt, E. L.

    1987-01-01

    Populations of indigenous Bradyrhizobium japonicum serocluster 123 and serogroups 110 and 138 were studied after various sugars were added to their soil habitat. Loam soil with approximately 104 cells of each group per g of soil were amended every 3 days with 0.1% glucose, sucrose, arabinose, xylose, or galactose. Enumerations of the populations were made every 12 days by immunofluorescence assay. Each B. japonicum population in the sugar-treated soils increased by about 1 log during the first 12 days, to a maximum of about 106 cells by day 36 or 48, irrespective of the sugar added. Maximum growth rates were similar for each group and occurred during the 12-day incubation period. The most rapid growth was in response to arabinose, with a mean generation time of about 3.0 days. Other mean doubling times were 4.0 days with glucose and galactose treatments, 4.5 days with xylose treatment, and 5.4 days with sucrose amendment. These data provide the first direct evidence that indigenous soil rhizobia can compete successfully with other soil bacteria for readily available substrates in soil in the absence of host legume roots or other rhizospheres. The growth rates in soil of the specific B. japonicum populations studied were nearly the same with a given sugar treatment but varied considerably with different sugars. The mean generation times of 3 to 5 days are among the first reported growth rates for heterotrophic bacteria in natural soil. PMID:16347412

  6. Extreme ecological response of a seabird community to unprecedented sea ice cover.

    PubMed

    Barbraud, Christophe; Delord, Karine; Weimerskirch, Henri

    2015-05-01

    Climate change has been predicted to reduce Antarctic sea ice but, instead, sea ice surrounding Antarctica has expanded over the past 30 years, albeit with contrasted regional changes. Here we report a recent extreme event in sea ice conditions in East Antarctica and investigate its consequences on a seabird community. In early 2014, the Dumont d'Urville Sea experienced the highest magnitude sea ice cover (76.8%) event on record (1982-2013: range 11.3-65.3%; mean±95% confidence interval: 27.7% (23.1-32.2%)). Catastrophic effects were detected in the breeding output of all sympatric seabird species, with a total failure for two species. These results provide a new view crucial to predictive models of species abundance and distribution as to how extreme sea ice events might impact an entire community of top predators in polar marine ecosystems in a context of expanding sea ice in eastern Antarctica.

  7. Investigating the Responses of Human Epithelial Cells to Predatory Bacteria

    PubMed Central

    Monnappa, Ajay K.; Bari, Wasimul; Choi, Seong Yeol; Mitchell, Robert J.

    2016-01-01

    One beguiling alternative to antibiotics for treating multi-drug resistant infections are Bdellovibrio-and-like-organisms (BALOs), predatory bacteria known to attack human pathogens. Consequently, in this study, the responses from four cell lines (three human and one mouse) were characterized during an exposure to different predatory bacteria, Bdellovibrio bacteriovorus HD100, Bacteriovorus BY1 and Bacteriovorax stolpii EB1. TNF-α levels were induced in Raw 264.7 mouse macrophage cultures with each predator, but paled in comparison to those obtained with E. coli. This was true even though the latter strain was added at an 11.1-fold lower concentration (p < 0.01). Likewise, E. coli led to a significant (54%) loss in the Raw 264.7 murine macrophage viability while the predatory strains had no impact. Tests with various epithelial cells, including NuLi-1 airway, Caco2, HT29 and T84 colorectal cells, gave similar results, with E. coli inducing IL-8 production. The viabilities of the NuLi-1 and Caco-2 cells were slightly reduced (8%) when exposed to the predators, while T84 viability remained steady. In no cases did the predatory bacteria induce actin rearrangement. These results clearly demonstrate the gentle natures of predatory bacteria and their impacts on human cells. PMID:27629536

  8. Investigating the phytohormone ethylene response pathway by chemical genetics.

    PubMed

    Lin, Lee-Chung; Chueh, Chiao-Mei; Wang, Long-Chi

    2014-01-01

    Conventional mutant screening in forward genetics research is indispensible to understand the biological operation behind any given phenotype. However, several issues, such as functional redundancy and lethality or sterility resulting from null mutations, frequently impede the functional characterization of genetic mutants. As an alternative approach, chemical screening with natural products or synthetic small molecules that act as conditional mutagens allows for identifying bioactive compounds as bioprobes to overcome the above-mentioned issues. Ethylene is the simplest olefin and is one of the major phytohormones playing crucial roles in plant physiology. Most of the current information on how ethylene works in plants came primarily from genetic studies of ethylene mutants identified by conventional genetic screening two decades ago. However, we lack a complete picture of functional interaction among components in the ethylene pathway and cross talk of ethylene with other phytohormones. Here, we describe our methodology for using chemical genetics to identify small molecules that interfere with the ethylene response. We set up a phenotype-based screening platform and a reporter gene-based system for verification of the hit compounds identified by chemical screening. We have successfully identified small molecules affecting the ethylene phenotype in etiolated seedlings and showed that a group of structurally similar compounds are novel inhibitors of ACC synthase, a rate-limiting enzyme in the ethylene biosynthesis pathway.

  9. Investigating the Responses of Human Epithelial Cells to Predatory Bacteria.

    PubMed

    Monnappa, Ajay K; Bari, Wasimul; Choi, Seong Yeol; Mitchell, Robert J

    2016-01-01

    One beguiling alternative to antibiotics for treating multi-drug resistant infections are Bdellovibrio-and-like-organisms (BALOs), predatory bacteria known to attack human pathogens. Consequently, in this study, the responses from four cell lines (three human and one mouse) were characterized during an exposure to different predatory bacteria, Bdellovibrio bacteriovorus HD100, Bacteriovorus BY1 and Bacteriovorax stolpii EB1. TNF-α levels were induced in Raw 264.7 mouse macrophage cultures with each predator, but paled in comparison to those obtained with E. coli. This was true even though the latter strain was added at an 11.1-fold lower concentration (p < 0.01). Likewise, E. coli led to a significant (54%) loss in the Raw 264.7 murine macrophage viability while the predatory strains had no impact. Tests with various epithelial cells, including NuLi-1 airway, Caco2, HT29 and T84 colorectal cells, gave similar results, with E. coli inducing IL-8 production. The viabilities of the NuLi-1 and Caco-2 cells were slightly reduced (8%) when exposed to the predators, while T84 viability remained steady. In no cases did the predatory bacteria induce actin rearrangement. These results clearly demonstrate the gentle natures of predatory bacteria and their impacts on human cells. PMID:27629536

  10. Developmental models for estimating ecological responses to environmental variability: structural, parametric, and experimental issues.

    PubMed

    Moore, Julia L; Remais, Justin V

    2014-03-01

    Developmental models that account for the metabolic effect of temperature variability on poikilotherms, such as degree-day models, have been widely used to study organism emergence, range and development, particularly in agricultural and vector-borne disease contexts. Though simple and easy to use, structural and parametric issues can influence the outputs of such models, often substantially. Because the underlying assumptions and limitations of these models have rarely been considered, this paper reviews the structural, parametric, and experimental issues that arise when using degree-day models, including the implications of particular structural or parametric choices, as well as assumptions that underlie commonly used models. Linear and non-linear developmental functions are compared, as are common methods used to incorporate temperature thresholds and calculate daily degree-days. Substantial differences in predicted emergence time arose when using linear versus non-linear developmental functions to model the emergence time in a model organism. The optimal method for calculating degree-days depends upon where key temperature threshold parameters fall relative to the daily minimum and maximum temperatures, as well as the shape of the daily temperature curve. No method is shown to be universally superior, though one commonly used method, the daily average method, consistently provides accurate results. The sensitivity of model projections to these methodological issues highlights the need to make structural and parametric selections based on a careful consideration of the specific biological response of the organism under study, and the specific temperature conditions of the geographic regions of interest. When degree-day model limitations are considered and model assumptions met, the models can be a powerful tool for studying temperature-dependent development.

  11. Developmental models for estimating ecological responses to environmental variability: structural, parametric, and experimental issues

    PubMed Central

    Moore, Julia L

    2014-01-01

    Developmental models that account for the metabolic effect of temperature variability on poikilotherms, such as degree-day models, have been widely used to study organism emergence, range and development, particularly in agricultural and vector-borne disease contexts. Though simple and easy to use, structural and parametric issues can influence the outputs of such models, often substantially. Because the underlying assumptions and limitations of these models have rarely been considered, this paper reviews the structural, parametric, and experimental issues that arise when using degree-day models, including the implications of particular structural or parametric choices, as well as assumptions that underlie commonly used models. Linear and nonlinear developmental functions are compared, as are common methods used to incorporate temperature thresholds and calculate daily degree-days. Substantial differences in predicted emergence time arose when using linear vs. non-linear developmental functions to model the emergence time in a model organism. The optimal method for calculating degree-days depends upon where key temperature threshold parameters fall relative to the daily minimum and maximum temperatures, as well as the shape of the daily temperature curve. No method is shown to be universally superior, though one commonly used method, the daily average method, consistently provides accurate results. The sensitivity of model projections to these methodological issues highlights the need to make structural and parametric selections based on a careful consideration of the specific biological response of the organism under study, and the specific temperature conditions of the geographic regions of interest. When degree-day model limitations are considered and model assumptions met, the models can be a powerful tool for studying temperature-dependent development. PMID:24443079

  12. Incorporating channel network information in hydrologic response modelling: model development and validation using ecologically relevant indicators

    NASA Astrophysics Data System (ADS)

    Biswal, B.; Singh, R.

    2015-12-01

    Many studies in the past have revealed that hydrologic response of a basin carries imprints of its channel network. However, accurate representation of channel networks in hydrologic models has been a challenge. In addition, dominating flow processes during high flow periods are not the same as those during recession periods, and there is a need for models that can represent these varying behaviors. In this study, we develop two model structures that aim to address the challenges above. The first model assumes that flow processes can be classified into two main categories: i) pure surface flow (PSF) and ii) mixed surface-subsurface flow (MSSF). The second model is a special case of the first model which neglects PSF. Using channel networks extracted from digital elevation models, we develop instantaneous unit hydrographs (IUHs) separately for PSF (PSFIUHs) and MSSF (MSSFIUHs). PSFIUH is descried by the channel 'network width function', whereas MSSFIUH is obtained by modifying a recently developed channel network morphology based recession flow model. To obtain the simulated streamflow time series for a basin, we convolute the PSFIUH and the MSSFIUH with the respective effective rainfall time series. The effective rainfall time series is obtained by using the probability distributed model (PDM). For comparison purposes, we also use a dual linear-bucket model for routing flow. Comparing model performance across 78 watersheds in the United States using the Nash Sutcliffe efficiency (NSE), we find that the two model structures that incorporate channel network information outperform the linear-bucket model in 56 watersheds. Further testing model performance using indicators that capture frequency and duration of low and high flows shows that the two developed models outperform the linear-bucket model in four out of five indicators.

  13. 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.

  14. 33 CFR 133.23 - Investigation to determine the source and responsible party.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND; STATE ACCESS § 133.23 Investigation to determine the source and...

  15. 33 CFR 133.23 - Investigation to determine the source and responsible party.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND; STATE ACCESS § 133.23 Investigation to determine the source and...

  16. 33 CFR 133.23 - Investigation to determine the source and responsible party.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND; STATE ACCESS § 133.23 Investigation to determine the source and...

  17. 33 CFR 133.23 - Investigation to determine the source and responsible party.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND; STATE ACCESS § 133.23 Investigation to determine the source and...

  18. 33 CFR 133.23 - Investigation to determine the source and responsible party.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND; STATE ACCESS § 133.23 Investigation to determine the source and...

  19. Extreme ecological response of a seabird community to unprecedented sea ice cover

    PubMed Central

    Barbraud, Christophe; Delord, Karine; Weimerskirch, Henri

    2015-01-01

    Climate change has been predicted to reduce Antarctic sea ice but, instead, sea ice surrounding Antarctica has expanded over the past 30 years, albeit with contrasted regional changes. Here we report a recent extreme event in sea ice conditions in East Antarctica and investigate its consequences on a seabird community. In early 2014, the Dumont d'Urville Sea experienced the highest magnitude sea ice cover (76.8%) event on record (1982–2013: range 11.3–65.3%; mean±95% confidence interval: 27.7% (23.1–32.2%)). Catastrophic effects were detected in the breeding output of all sympatric seabird species, with a total failure for two species. These results provide a new view crucial to predictive models of species abundance and distribution as to how extreme sea ice events might impact an entire community of top predators in polar marine ecosystems in a context of expanding sea ice in eastern Antarctica. PMID:26064653

  20. Immunohistochemical investigation of wound healing in response to fractional photothermolysis

    NASA Astrophysics Data System (ADS)

    Helbig, Doris; Bodendorf, Marc Oliver; Grunewald, Sonja; Kendler, Michael; Simon, Jan C.; Paasch, Uwe

    2009-11-01

    Despite growing clinical evidence of ablative fractional photothermolysis (AFP), little is known about the spatiotemporal molecular changes within the targeted compartments. Six subjects received three different single AFP treatments using a scanned 250 μm CO2-laser beam. Spatiotemporal changes of skin regeneration were estimated by immunohistochemical investigation (HSP70, HSP72, HSP47, TGFβ, procollagen III, CD3, CD20, and CD68) in skin samples 1 h, 3 days, and 14 days postintervention. The remodeling was uniformly started by regrowth of the epidermal compartment followed by partial to complete replacement of the microscopic ablation zones (MAZ) by newly synthesized condensed procollagen III. From day 3 to 14, the number of macrophages as well as giant cells surrounding the MAZ increased. TGFβ expression was highest 1 h to 3 days following AFP. HSP70 and HSP72 expressions were highest 3-14 days postintervention in the spinocellular layer leading to an upregulation of HSP47. AFP performed by a scanned CO2-laser results in an early epidermal remodeling, which is followed by a dermal remodeling leading to a replacement of the MAZ with newly synthesized (pro)-collagen. During this, an inflammatory infiltrate with CD3+ and CD20+ cells surrounds the MAZ. The count of macrophages and giant cells involved in the replacement of the necrotic zones seems to be crucial for wound healing.

  1. Administrative Ecology

    ERIC Educational Resources Information Center

    McGarity, Augustus C., III; Maulding, Wanda

    2007-01-01

    This article discusses how all four facets of administrative ecology help dispel the claims about the "impossibility" of the superintendency. These are personal ecology, professional ecology, organizational ecology, and community ecology. Using today's superintendency as an administrative platform, current literature describes a preponderance of…

  2. Coccolithophore paleoproductivity and ecology response to deglacial and Holocene changes in the Azores Current System

    NASA Astrophysics Data System (ADS)

    Schwab, C.; Kinkel, H.; Weinelt, M.; RepschläGer, J.

    2012-09-01

    In order to test the sensitivity of marine primary productivity in the midlatitude open ocean North Atlantic to changes in the Atlantic Meridional Overturning Circulation (AMOC), we investigated two spliced sediment cores from a site south of the Azores Islands at the northern rim of the North Atlantic subtropical gyre. For this purpose we analyzed coccolithophore assemblages, diatom abundances, alkenones and conducted X-ray fluorescence (XRF) core scanning. During times of reduced AMOC, especially during Heinrich event 1 (H1) and the Younger Dryas, we observe a strong increase in productivity as evidenced by high coccolith accumulation rates, high alkenone concentrations/accumulation rates, high Ba/Ti-ratios, high abundances of diatoms and low abundances ofF. profunda. The increased productivity is partly caused by a more southern position of the Azores Front (AzF), and hence by a less northward extension of the subtropical gyre, as deduced from high abundances of the temperate coccolithophore species G. muellerae and low abundances of subtropical species (Oolithotus spp., Umbellosphaera spp., Umbilicosphaeraspp.). However, to explain the full range of the observed productivity increase, other factors like increased westerly winds and advection of nutrient-rich surface waters have also to be considered. Because this pattern can also be observed in other sediment cores from the midlatitude North Atlantic, we propose that during times of reduced AMOC there has been a band of strongly increased productivity across the North Atlantic at the northern rim of the contracted subtropical gyre, which partly counteracts the decreased organic carbon pump in the high northern latitudes.

  3. Microbiological and ecological responses to global environmental changes in polar regions (MERGE): An IPY core coordinating project

    NASA Astrophysics Data System (ADS)

    Naganuma, Takeshi; Wilmotte, Annick

    2009-11-01

    An integrated program, “Microbiological and ecological responses to global environmental changes in polar regions” (MERGE), was proposed in the International Polar Year (IPY) 2007-2008 and endorsed by the IPY committee as a coordinating proposal. MERGE hosts original proposals to the IPY and facilitates their funding. MERGE selected three key questions to produce scientific achievements. Prokaryotic and eukaryotic organisms in terrestrial, lacustrine, and supraglacial habitats were targeted according to diversity and biogeography; food webs and ecosystem evolution; and linkages between biological, chemical, and physical processes in the supraglacial biome. MERGE hosted 13 original and seven additional proposals, with two full proposals. It respected the priorities and achievements of the individual proposals and aimed to unify their significant results. Ideas and projects followed a bottom-up rather than a top-down approach. We intend to inform the MERGE community of the initial results and encourage ongoing collaboration. Scientists from non-polar regions have also participated and are encouraged to remain involved in MERGE. MERGE is formed by scientists from Argentina, Australia, Austria, Belgium, Brazil, Bulgaria, Canada, Egypt, Finland, France, Germany, Italy, Japan, Korea, Malaysia, New Zealand, Philippines, Poland, Russia, Spain, UK, Uruguay, USA, and Vietnam, and associates from Chile, Denmark, Netherlands, and Norway.

  4. Responses to colour and host odour cues in three cereal pest species, in the context of ecology and control.

    PubMed

    Arnold, S E J; Stevenson, P C; Belmain, S R

    2015-08-01

    Many insects show a greater attraction to multimodal cues, e.g. odour and colour combined, than to either cue alone. Despite the potential to apply the knowledge to improve control strategies, studies of multiple stimuli have not been undertaken for stored product pest insects. We tested orientation towards a food odour (crushed white maize) in combination with a colour cue (coloured paper with different surface spectral reflectance properties) in three storage pest beetle species, using motion tracking to monitor their behaviour. While the maize weevil, Sitophilus zeamais (Motsch.), showed attraction to both odour and colour stimuli, particularly to both cues in combination, this was not observed in the bostrichid pests Rhyzopertha dominica (F.) (lesser grain borer) or Prostephanus truncatus (Horn) (larger grain borer). The yellow stimulus was particularly attractive to S. zeamais, and control experiments showed that this was neither a result of the insects moving towards darker-coloured areas of the arena, nor their being repelled by optical brighteners in white paper. Visual stimuli may play a role in location of host material by S. zeamais, and can be used to inform trap design for the control or monitoring of maize weevils. The lack of visual responses by the two grain borers is likely to relate to their different host-seeking behaviours and ecological background, which should be taken into account when devising control methods. PMID:25916219

  5. Responses to colour and host odour cues in three cereal pest species, in the context of ecology and control.

    PubMed

    Arnold, S E J; Stevenson, P C; Belmain, S R

    2015-08-01

    Many insects show a greater attraction to multimodal cues, e.g. odour and colour combined, than to either cue alone. Despite the potential to apply the knowledge to improve control strategies, studies of multiple stimuli have not been undertaken for stored product pest insects. We tested orientation towards a food odour (crushed white maize) in combination with a colour cue (coloured paper with different surface spectral reflectance properties) in three storage pest beetle species, using motion tracking to monitor their behaviour. While the maize weevil, Sitophilus zeamais (Motsch.), showed attraction to both odour and colour stimuli, particularly to both cues in combination, this was not observed in the bostrichid pests Rhyzopertha dominica (F.) (lesser grain borer) or Prostephanus truncatus (Horn) (larger grain borer). The yellow stimulus was particularly attractive to S. zeamais, and control experiments showed that this was neither a result of the insects moving towards darker-coloured areas of the arena, nor their being repelled by optical brighteners in white paper. Visual stimuli may play a role in location of host material by S. zeamais, and can be used to inform trap design for the control or monitoring of maize weevils. The lack of visual responses by the two grain borers is likely to relate to their different host-seeking behaviours and ecological background, which should be taken into account when devising control methods.

  6. Response to Ecological Risk Assessment Forum Request for Information on the Benefits of PCB Congener-Specific Analyses

    EPA Science Inventory

    In August, 2001, the Ecological Risk Assessment Forum (ERAF) submitted a formal question to the Ecological Risk Assessment Support Center (ERASC) on the benefits of evaluating PCB congeners in environmental samples. This question was developed by ERAF members Bruce Duncan and Cla...

  7. Study on the Response of Ecological Capacity to Land-Use/Cover Change in Wuhan City: A Remote Sensing and GIS Based Approach

    PubMed Central

    Wang, Ying; Li, Xiangmei

    2014-01-01

    This research examined the spatiotemporal patterns of land-use/cover and the dynamics of ecological capacity in response to land-use/cover change in Wuhan city, central China. The data were derived from five years' remote-sensed images, that is, 1990, 1995, 2000, 2005, and 2010. This paper used an integrated approach of remote sensing and GIS techniques, ecological capacity and the bilateral dynamic degree models. The results are as follows. (1) From 1990 to 2010, remarkable changes in land-use/cover have occurred within the studied area, and the most prominent characteristics of the changes were continuous decline of arable land and rapid increase of built-up land. (2) The total ecological capacity dropped from 450.55 × 104 ghm2 in 1990 to 447.35 × 104 ghm2 in 2010. The eastern, western, and southern parts had higher ecological capacity whereas the northwestern hilly areas and the central district had lower ecological capacity. (3) Due to the conversion from arable land to built-up land, the ecological capacity losses during 1990–1995, 1995–2000, 2000–2005, and 2005–2010 were 155.52 × 102 ghm2, 114.12 × 102 ghm2, 455.48 × 102 ghm2, and 325.26 × 102 ghm2, respectively. The study would contribute to better understanding of the effects of land-use dynamics and the evolution of ecological capacity, which can provide scientific basis for land management and environment protection. PMID:25258734

  8. Study on the response of ecological capacity to land-use/cover change in Wuhan city: a remote sensing and GIS based approach.

    PubMed

    Wang, Ying; Li, Xiangmei; Li, Jiangfeng

    2014-01-01

    This research examined the spatiotemporal patterns of land-use/cover and the dynamics of ecological capacity in response to land-use/cover change in Wuhan city, central China. The data were derived from five years' remote-sensed images, that is, 1990, 1995, 2000, 2005, and 2010. This paper used an integrated approach of remote sensing and GIS techniques, ecological capacity and the bilateral dynamic degree models. The results are as follows. (1) From 1990 to 2010, remarkable changes in land-use/cover have occurred within the studied area, and the most prominent characteristics of the changes were continuous decline of arable land and rapid increase of built-up land. (2) The total ecological capacity dropped from 450.55 × 10(4) ghm(2) in 1990 to 447.35 × 10(4) ghm(2) in 2010. The eastern, western, and southern parts had higher ecological capacity whereas the northwestern hilly areas and the central district had lower ecological capacity. (3) Due to the conversion from arable land to built-up land, the ecological capacity losses during 1990-1995, 1995-2000, 2000-2005, and 2005-2010 were 155.52 × 10(2) ghm(2), 114.12 × 10(2) ghm(2), 455.48 × 10(2) ghm(2), and 325.26 × 10(2) ghm(2), respectively. The study would contribute to better understanding of the effects of land-use dynamics and the evolution of ecological capacity, which can provide scientific basis for land management and environment protection.

  9. Study on the response of ecological capacity to land-use/cover change in Wuhan city: a remote sensing and GIS based approach.

    PubMed

    Wang, Ying; Li, Xiangmei; Li, Jiangfeng

    2014-01-01

    This research examined the spatiotemporal patterns of land-use/cover and the dynamics of ecological capacity in response to land-use/cover change in Wuhan city, central China. The data were derived from five years' remote-sensed images, that is, 1990, 1995, 2000, 2005, and 2010. This paper used an integrated approach of remote sensing and GIS techniques, ecological capacity and the bilateral dynamic degree models. The results are as follows. (1) From 1990 to 2010, remarkable changes in land-use/cover have occurred within the studied area, and the most prominent characteristics of the changes were continuous decline of arable land and rapid increase of built-up land. (2) The total ecological capacity dropped from 450.55 × 10(4) ghm(2) in 1990 to 447.35 × 10(4) ghm(2) in 2010. The eastern, western, and southern parts had higher ecological capacity whereas the northwestern hilly areas and the central district had lower ecological capacity. (3) Due to the conversion from arable land to built-up land, the ecological capacity losses during 1990-1995, 1995-2000, 2000-2005, and 2005-2010 were 155.52 × 10(2) ghm(2), 114.12 × 10(2) ghm(2), 455.48 × 10(2) ghm(2), and 325.26 × 10(2) ghm(2), respectively. The study would contribute to better understanding of the effects of land-use dynamics and the evolution of ecological capacity, which can provide scientific basis for land management and environment protection. PMID:25258734

  10. Birds in Anthropogenic Landscapes: The Responses of Ecological Groups to Forest Loss in the Brazilian Atlantic Forest.

    PubMed

    Morante-Filho, José Carlos; Faria, Deborah; Mariano-Neto, Eduardo; Rhodes, Jonathan

    2015-01-01

    Habitat loss is the dominant threat to biodiversity and ecosystem functioning in terrestrial environments. In this study, we used an a priori classification of bird species based on their dependence on native forest habitats (forest-specialist and habitat generalists) and specific food resources (frugivores and insectivores) to evaluate their responses to forest cover reduction in landscapes in the Brazilian Atlantic Forest. From the patch-landscapes approach, we delimited 40 forest sites, and quantified the percentage of native forest within a 2 km radius around the center of each site (from 6 - 85%). At each site, we sampled birds using the point-count method. We used a null model, a generalized linear model and a four-parameter logistic model to evaluate the relationship between richness and abundance of the bird groups and the native forest amount. A piecewise model was then used to determine the threshold value for bird groups that showed nonlinear responses. The richness and abundance of the bird community as a whole were not affected by changes in forest cover in this region. However, a decrease in forest cover had a negative effect on diversity of forest-specialist, frugivorous and insectivorous birds, and a positive effect on generalist birds. The species richness and abundance of all ecological groups were nonlinearly related to forest reduction and showed similar threshold values, i.e., there were abrupt changes in individuals and species numbers when forest amount was less than approximately 50%. Forest sites within landscapes with forest cover that was less than 50% contained a different bird species composition than more extensively forested sites and had fewer forest-specialist species and higher beta-diversity. Our study demonstrated the pervasive effect of forest reduction on bird communities in one of the most important hotspots for bird conservation and shows that many vulnerable species require extensive forest cover to persist. PMID:26083245

  11. Birds in Anthropogenic Landscapes: The Responses of Ecological Groups to Forest Loss in the Brazilian Atlantic Forest

    PubMed Central

    Morante-Filho, José Carlos; Rhodes, Jonathan

    2015-01-01

    Habitat loss is the dominant threat to biodiversity and ecosystem functioning in terrestrial environments. In this study, we used an a priori classification of bird species based on their dependence on native forest habitats (forest-specialist and habitat generalists) and specific food resources (frugivores and insectivores) to evaluate their responses to forest cover reduction in landscapes in the Brazilian Atlantic Forest. From the patch-landscapes approach, we delimited 40 forest sites, and quantified the percentage of native forest within a 2 km radius around the center of each site (from 6 - 85%). At each site, we sampled birds using the point-count method. We used a null model, a generalized linear model and a four-parameter logistic model to evaluate the relationship between richness and abundance of the bird groups and the native forest amount. A piecewise model was then used to determine the threshold value for bird groups that showed nonlinear responses. The richness and abundance of the bird community as a whole were not affected by changes in forest cover in this region. However, a decrease in forest cover had a negative effect on diversity of forest-specialist, frugivorous and insectivorous birds, and a positive effect on generalist birds. The species richness and abundance of all ecological groups were nonlinearly related to forest reduction and showed similar threshold values, i.e., there were abrupt changes in individuals and species numbers when forest amount was less than approximately 50%. Forest sites within landscapes with forest cover that was less than 50% contained a different bird species composition than more extensively forested sites and had fewer forest-specialist species and higher beta-diversity. Our study demonstrated the pervasive effect of forest reduction on bird communities in one of the most important hotspots for bird conservation and shows that many vulnerable species require extensive forest cover to persist. PMID:26083245

  12. Birds in Anthropogenic Landscapes: The Responses of Ecological Groups to Forest Loss in the Brazilian Atlantic Forest.

    PubMed

    Morante-Filho, José Carlos; Faria, Deborah; Mariano-Neto, Eduardo; Rhodes, Jonathan

    2015-01-01

    Habitat loss is the dominant threat to biodiversity and ecosystem functioning in terrestrial environments. In this study, we used an a priori classification of bird species based on their dependence on native forest habitats (forest-specialist and habitat generalists) and specific food resources (frugivores and insectivores) to evaluate their responses to forest cover reduction in landscapes in the Brazilian Atlantic Forest. From the patch-landscapes approach, we delimited 40 forest sites, and quantified the percentage of native forest within a 2 km radius around the center of each site (from 6 - 85%). At each site, we sampled birds using the point-count method. We used a null model, a generalized linear model and a four-parameter logistic model to evaluate the relationship between richness and abundance of the bird groups and the native forest amount. A piecewise model was then used to determine the threshold value for bird groups that showed nonlinear responses. The richness and abundance of the bird community as a whole were not affected by changes in forest cover in this region. However, a decrease in forest cover had a negative effect on diversity of forest-specialist, frugivorous and insectivorous birds, and a positive effect on generalist birds. The species richness and abundance of all ecological groups were nonlinearly related to forest reduction and showed similar threshold values, i.e., there were abrupt changes in individuals and species numbers when forest amount was less than approximately 50%. Forest sites within landscapes with forest cover that was less than 50% contained a different bird species composition than more extensively forested sites and had fewer forest-specialist species and higher beta-diversity. Our study demonstrated the pervasive effect of forest reduction on bird communities in one of the most important hotspots for bird conservation and shows that many vulnerable species require extensive forest cover to persist.

  13. Investigations of the Climate System Response to Climate Engineering in a Hierarchy of Models

    NASA Astrophysics Data System (ADS)

    McCusker, Kelly E.

    Global warming due to anthropogenic emissions of greenhouse gases is causing negative impacts on diverse ecological and human systems around the globe, and these impacts are projected to worsen as climate continues to warm. In the absence of meaningful greenhouse gas emissions reductions, new strategies have been proposed to engineer the climate, with the aim of preventing further warming and avoiding associated climate impacts. We investigate one such strategy here, falling under the umbrella of `solar radiation management', in which sulfate aerosols are injected into the stratosphere. We use a global climate model with a coupled mixed-layer depth ocean and with a fully-coupled ocean general circulation model to simulate the stabilization of climate by balancing increasing carbon dioxide with increasing stratospheric sulfate concentrations. We evaluate whether or not severe climate impacts, such as melting Arctic sea ice, tropical crop failure, or destabilization of the West Antarctic ice sheet, could be avoided. We find that while tropical climate emergencies might be avoided by use of stratospheric aerosol injections, avoiding polar emergencies cannot be guaranteed due to large residual climate changes in those regions, which are in part due to residual atmospheric circulation anomalies. We also find that the inclusion of a fully-coupled ocean is important for determining the regional climate response because of its dynamical feedbacks. The efficacy of stratospheric sulfate aerosol injections, and solar radiation management more generally, depends on its ability to be maintained indefinitely, without interruption from a variety of possible sources, such as technological failure, a breakdown in global cooperation, lack of funding, or negative unintended consequences. We next consider the scenario in which stratospheric sulfate injections are abruptly terminated after a multi- decadal period of implementation while greenhouse gas emissions have continued unabated

  14. Investigating variation in the nutritional ecology and genetics of White-tailed Ptarmigan: implications for climate change

    NASA Astrophysics Data System (ADS)

    Oyler-McCance, S. J.; Stricker, C. A.; Braun, C. E.; Wann, G. T.; Aldridge, C. L.

    2010-12-01

    White-tailed Ptarmigan (Lagopus leucura) are well suited as a focal species for the study of climate change because they are adapted to cool, alpine environments that are expected to undergo unusually rapid climate change. We compared samples collected in the late 1930s, the late 1960s, and the late 2000s using molecular genetic and stable isotope methods in an effort to determine whether White-tailed Ptarmigan on Mt. Evans, Colorado have experienced recent environmental changes resulting in shifts in genetic diversity, gene frequency, and nutritional ecology. We genotyped 115 individuals spanning the three time periods using nine polymorphic microsatellite loci in our genetic analysis. These samples were also analyzed for stable carbon and nitrogen isotopic composition. We found a slight trend of lower heterozygosity through time and allelic richness values were lower in more recent times. We found no changes in allele frequencies across time periods suggesting that population sizes have not changed dramatically. Feather δ13C and δ15N values decreased significantly across time periods, whereas the range in isotope values increased consistently from the late 1930s to the later time periods. Inferred changes in the nutritional ecology of White-tailed Ptarmigan on Mt. Evans relates primarily to increased atmospheric deposition of nutrients that likely influenced foraging habits and tundra plant composition and nutritional quality. We briefly discuss similar ongoing work on the neighboring population in Rocky Mountain National Park, Colorado and tie in genetic results from across the species range.

  15. Aquatic vegetation in response to increased eutrophication and degraded light climate in Eastern Lake Taihu: Implications for lake ecological restoration

    NASA Astrophysics Data System (ADS)

    Zhang, Yunlin; Liu, Xiaohan; Qin, Boqiang; Shi, Kun; Deng, Jianming; Zhou, Yongqiang

    2016-04-01

    Terrestrial and aquatic ecosystem degradation is widely recognized as a major global environmental and development problem. Although great efforts have been made to prevent aquatic ecosystem degradation, the degree, extent and impacts of this phenomenon remain controversial and unclear, such as its driving mechanisms. Here, we present results from a 17-year field investigation (1998–2014) of water quality and a 12-year remote sensing mapping (2003–2014) of the aquatic vegetation presence frequency (VPF) in Eastern Lake Taihu, a macrophyte-dominated bay of Lake Taihu in China. In the past 17 years, nutrient concentrations and water level (WL) have significantly increased, but the Secchi disk depth (SDD) has significantly decreased. These changes were associated with increased lake eutrophication and a degraded underwater light climate that further inhibited the growth of aquatic vegetation. In Eastern Lake Taihu, increased nutrients, chlorophyll a and WL, and a decreased SDD were all significantly correlated with a decreased VPF. NH4+-N concentration and SDD/WL were the most important controlling factors for VPF. Therefore, increased anthropogenic nutrient inputs and a degraded underwater light climate surely result in a decreased VPF. These results elucidate the driving mechanism of aquatic vegetation degradation and will facilitate Lake Taihu ecological restoration.

  16. Aquatic vegetation in response to increased eutrophication and degraded light climate in Eastern Lake Taihu: Implications for lake ecological restoration.

    PubMed

    Zhang, Yunlin; Liu, Xiaohan; Qin, Boqiang; Shi, Kun; Deng, Jianming; Zhou, Yongqiang

    2016-01-01

    Terrestrial and aquatic ecosystem degradation is widely recognized as a major global environmental and development problem. Although great efforts have been made to prevent aquatic ecosystem degradation, the degree, extent and impacts of this phenomenon remain controversial and unclear, such as its driving mechanisms. Here, we present results from a 17-year field investigation (1998-2014) of water quality and a 12-year remote sensing mapping (2003-2014) of the aquatic vegetation presence frequency (VPF) in Eastern Lake Taihu, a macrophyte-dominated bay of Lake Taihu in China. In the past 17 years, nutrient concentrations and water level (WL) have significantly increased, but the Secchi disk depth (SDD) has significantly decreased. These changes were associated with increased lake eutrophication and a degraded underwater light climate that further inhibited the growth of aquatic vegetation. In Eastern Lake Taihu, increased nutrients, chlorophyll a and WL, and a decreased SDD were all significantly correlated with a decreased VPF. NH4(+)-N concentration and SDD/WL were the most important controlling factors for VPF. Therefore, increased anthropogenic nutrient inputs and a degraded underwater light climate surely result in a decreased VPF. These results elucidate the driving mechanism of aquatic vegetation degradation and will facilitate Lake Taihu ecological restoration. PMID:27041062

  17. Aquatic vegetation in response to increased eutrophication and degraded light climate in Eastern Lake Taihu: Implications for lake ecological restoration

    PubMed Central

    Zhang, Yunlin; Liu, Xiaohan; Qin, Boqiang; Shi, Kun; Deng, Jianming; Zhou, Yongqiang

    2016-01-01

    Terrestrial and aquatic ecosystem degradation is widely recognized as a major global environmental and development problem. Although great efforts have been made to prevent aquatic ecosystem degradation, the degree, extent and impacts of this phenomenon remain controversial and unclear, such as its driving mechanisms. Here, we present results from a 17-year field investigation (1998–2014) of water quality and a 12-year remote sensing mapping (2003–2014) of the aquatic vegetation presence frequency (VPF) in Eastern Lake Taihu, a macrophyte-dominated bay of Lake Taihu in China. In the past 17 years, nutrient concentrations and water level (WL) have significantly increased, but the Secchi disk depth (SDD) has significantly decreased. These changes were associated with increased lake eutrophication and a degraded underwater light climate that further inhibited the growth of aquatic vegetation. In Eastern Lake Taihu, increased nutrients, chlorophyll a and WL, and a decreased SDD were all significantly correlated with a decreased VPF. NH4+-N concentration and SDD/WL were the most important controlling factors for VPF. Therefore, increased anthropogenic nutrient inputs and a degraded underwater light climate surely result in a decreased VPF. These results elucidate the driving mechanism of aquatic vegetation degradation and will facilitate Lake Taihu ecological restoration. PMID:27041062

  18. 77 FR 69631 - Draft Guidance for IRBs, Clinical Investigators, and Sponsors: IRB Responsibilities for Reviewing...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-20

    ... Persons with access to the Internet may obtain the document at http://www.fda.gov/ScienceResearch/Special... Sponsors: IRB Responsibilities for Reviewing the Qualifications of Investigators, Adequacy of Research... Responsibilities for Reviewing the Qualifications of Investigators, Adequacy of Research Sites, and...

  19. Investigating the Decision Heuristics of Candidate Teachers Who Are Different in Their Responsibility Controls

    ERIC Educational Resources Information Center

    Özen, Yener

    2016-01-01

    In this study, decision heuristics used by individuals with different responsibility controls were investigated. In the research, 370 final grade university students studying at Erzincan University Faculty of Education were included. In order to collect data, Internally Controlled Responsibility-Externally Controlled Responsibility Scale of Özen…

  20. Ecological Schoolyards.

    ERIC Educational Resources Information Center

    Danks, Sharon Gamson

    2000-01-01

    Presents design guidelines and organizational and site principles for creating schoolyards where students can learn about ecology. Principles for building schoolyard ecological systems are described. (GR)

  1. Taxonomic and nontaxonomic responses to ecological changes in an urban lowland stream through the use of Chironomidae (Diptera) larvae.

    PubMed

    Cortelezzi, A; Paggi, A C; Rodríguez, M; Capítulo, A Rodrigues

    2011-03-01

    Biotic descriptors--both taxonomic (diversity indices, species richness, and indicator species) and nontaxonomic (biomass, oxygen consumption/production, and anatomical deformities)--are useful tools for measuring a stream's ecological condition. Nontaxonomic parameters detect critical effects not reflected taxonomically. We analyzed changes in Chironomidae populations as taxonomic parameters and mentum deformities as a nontaxonomic parameter for evaluating a South-American-plains stream (Argentina). We performed samplings seasonally (March, June, September, and December; 2005) and physical and chemical measurements at three sampling sites of the stream (DC1 at river source, through DC3 downstream). The specimens collected in sediment and vegetation were analyzed to investigate mouth deformities in Chironomidae larvae. We identified a total of 9 taxa from Chironomidae and Orthocladiinae subfamilies. Shannon's diversity index for Chironomidae decreased from 1.6 bits ind⁻¹ (DC1) to 0.3 bits ind⁻¹ (DC3). The total density of the Chironomidae exhibited a great increase in abundance at site DC3, especially that of Chironomus calligraphus. Chironomidae taxonomic composition also changed among the three sites despite their spatial proximity: C. calligraphus, Goeldichironomus holoprasinus, Parachironomus longistilus, and Polypedilum were present at all three; Corynoneura and Paratanytarsu at DC1 only; Cricotopus at DC1 and DC3; Apedilum elachistus notably at DC2 and DC3; and Parametriocnemus only at DC2. C. calligraphus individuals from DC1 showed no mentum deformities; only 2 from DC2 exhibited mouth-structure alterations; while specimens from DC3 presented the most abnormalities, especially during autumn and late winter. Type-II deformities (supernumerary teeth and gaps) were the most common. Anatomical deformities are sublethal effects representing an early alert to chemically caused environmental degradation. Mentum deformities in benthic-Chironomidae larvae

  2. Do induced responses mediate the ecological interactions between the specialist herbivores and phytopathogens of an alpine plant?

    PubMed

    Röder, Gregory; Rahier, Martine; Naisbit, Russell E

    2011-01-01

    Plants are not passive victims of the myriad attackers that rely on them for nutrition. They have a suite of physical and chemical defences, and are even able to take advantage of the enemies of their enemies. These strategies are often only deployed upon attack, so may lead to indirect interactions between herbivores and phytopathogens. In this study we test for induced responses in wild populations of an alpine plant (Adenostyles alliariae) that possesses constitutive chemical defence (pyrrolizidine alkaloids) and specialist natural enemies (two species of leaf beetle, Oreina elongata and Oreina cacaliae, and the phytopathogenic rust Uromyces cacaliae). Plants were induced in the field using chemical elicitors of the jasmonic acid (JA) and salicylic acid (SA) pathways and monitored for one month under natural conditions. There was evidence for induced resistance, with lower probability and later incidence of attack by beetles in JA-induced plants and of rust infection in SA-induced plants. We also demonstrate ecological cross-effects, with reduced fungal attack following JA-induction, and a cost of SA-induction arising from increased beetle attack. As a result, there is the potential for negative indirect effects of the beetles on the rust, while in the field the positive indirect effect of the rust on the beetles appears to be over-ridden by direct effects on plant nutritional quality. Such interactions resulting from induced susceptibility and resistance must be considered if we are to exploit plant defences for crop protection using hormone elicitors or constitutive expression. More generally, the fact that induced defences are even found in species that possess constitutively-expressed chemical defence suggests that they may be ubiquitous in higher plants.

  3. Use of exposure-response bioassays on arabica punctulata for the determination of ecological risk. (Reannouncement with new availability information). Professional paper

    SciTech Connect

    Mueller, C.; Rogers, B.; Comeleo, P.; Jayaraman, S.; Munns, W.

    1992-11-01

    Two sea urchin exposure-response bioassays were conducted to develop a marine ecological risk assessment (ERA) model and to determine the effects of hazardous waste disposal at the Naval Construction Battalion Center (NCBC), Davisville,RI on the adjacent Allen Harbor and Narragansett Bay. Arbacia gametes and embryos were exposed for 20 min and 48 hr to serial dilutions of landfill-associated sediment extract and seep water samples to evaluate the effects of this disposal site on marine organisms. Successful fertilizations, normal and abnormal embryonic development, and 48 hr mortality were examined. Positive exposure-related responses were observed for both seep samples and sediment extracts. These models will be used to define current ecological risks to organisms representative of those in Allen Harbor.... Marine chemistry, Bentic flux.

  4. Ecological coassociations influence species' responses to past climatic change: an example from a Sonoran Desert bark beetle.

    PubMed

    Garrick, Ryan C; Nason, John D; Fernández-Manjarrés, Juan F; Dyer, Rodney J

    2013-06-01

    Ecologically interacting species may have phylogeographical histories that are shaped both by features of their abiotic landscape and by biotic constraints imposed by their coassociation. The Baja California peninsula provides an excellent opportunity to examine the influence of abiotic vs. biotic factors on patterns of diversity in plant-insect species.This is because past climatic and geological changes impacted the genetic structure of plants quite differently to that of codistributed free-living animals (e.g. herpetofauna and small mammals). Thus, 'plant-like' patterns should be discernible in host-specific insect herbivores. Here, we investigate the population history of a monophagous bark beetle, Araptus attenuatus, and consider drivers of phylogeographical patterns in the light of previous work on its host plant, Euphorbia lomelii. Using a combination of phylogenetic, coalescent-simulation-based and exploratory analyses of mitochondrial DNA sequences and nuclear genotypic data, we found that the evolutionary history of A. attenuatus exhibits similarities to its host plant that are attributable to both biotic and abiotic processes. Southward range expansion and recent colonization of continental Sonora from the Baja peninsula appear to be unique to this taxon pair and probably reflect influences of the host plant. On the other hand, abiotic factors with landscape level influences on a diverse suite of codistributed arid-adapted taxa, such as Plio- and Pleistocene-aged marine incursions in the region, also left genetic signatures in beetle and host plant populations. Superimposed on these similarities, bark beetle-specific patterns and processes were also evident: our data revealed two secondarily sympatric,reproductively isolated genetic lineages, as well as a previously unrecognized mid peninsular warm desert refuge. Taken together, this work illustrates that the evolutionary history of species-specific insect herbivores may represent a mosaic of influences

  5. Investigating social ecological contributors to diabetes within Hispanics in an underserved U.S.-Mexico border community.

    PubMed

    Chang, Jean; Guy, Mignonne C; Rosales, Cecilia; de Zapien, Jill G; Staten, Lisa K; Fernandez, Maria L; Carvajal, Scott C

    2013-07-31

    Hispanics bear a disproportionate burden of diabetes in the United States, yet relations of structural, socio-cultural and behavioral factors linked to diabetes are not fully understood across all of their communities. The current study examines disparities and factors associated with diabetes in adult Hispanics of Mexican-descent (N = 648) participating in a population survey of an underserved rural U.S.-Mexico border community. The overall rate of diabetes prevalence rate in the sample, based on self-report and a glucose testing, was 21%; much higher than rates reported for U.S. adults overall, for all Hispanic adults, or for Mexican American adults specifically. Acculturation markers and social determinants of health indicators were only significantly related to diabetes in models not accounting for age. Older age, greater BMI (>30), greater waist-to-hip ratio as well as lower fruit and vegetable consumption were significantly related to increased likelihood of diabetes when all structural, cultural, behavioral, and biological factors were considered. Models with sets of behavioral factors and biological factors each significantly improved explanation of diabetes relative to prior social ecological theory-guided models. The findings show a critical need for diabetes prevention efforts in this community and suggest that health promotion efforts should particularly focus on increasing fruit and vegetable consumption.

  6. Investigations on the Effects of Dietary Essential Oils and Different Husbandry Conditions on the Gut Ecology in Piglets after Weaning

    PubMed Central

    Janczyk, P.; Pieper, R.; Urubschurov, V.; Wendler, K. R.; Souffrant, W. B.

    2009-01-01

    Essential oils (EO) are being considered as possible alternatives to in-feed antibiotic growth promoters in pig nutrition. The effects of an EO mixture consisting of limonene, eugenol and pinene (10.0, 2.0, and 4.8 mg/kg diet, resp.) on gut physiology and ecology were studied in piglets. The experiment was conducted at low (commercial farm) and high hygienic conditions (experimental farm), to elucidate interactions between EO supplementation and husbandry methods. Piglets were weaned at 28 days of age, when they were offered either a control diet (C) or C with EO. Four piglets were sacrificed in each group on day 29, 30, 33 and 39. Digesta from the third distal part of the small intestine and from the colon were sampled and analysed for pH, dry matter, lactic acid, short chain fatty acids and ammonia concentrations. Enterobacteria, enterococci, lactobacilli and yeast counts were obtained by plating. Genomic DNA was extracted from digesta and polymerase chain reaction—denaturing gradient gel electrophoresis was performed. Individual microbial communities were identified at each farm. Age affected the intestinal parameters. No effects of the EO with exception for a significant reduction in colon bacterial diversity at 39 days of age could be recorded at experimental farm. PMID:20016670

  7. Investigating the impact of a smart growth community on the contexts of children's physical activity using Ecological Momentary Assessment.

    PubMed

    Dunton, Genevieve F; Intille, Stephen S; Wolch, Jennifer; Pentz, Mary Ann

    2012-01-01

    This quasi-experimental research used Ecological Momentary Assessment with electronic surveys delivered through mobile phones to determine whether children change the type of contexts (i.e., settings) where they engage in physical activity after a recent move to a smart growth (SG) community in the U.S. as compared to children living in conventional low-to-medium density U.S. suburban communities (controls). SG vs. control children engaged in a greater proportion of physical activity bouts with friends, a few blocks from home, and at locations to which they walked. Over six months, the proportion of physical activity bouts reported at home (indoors) and in high traffic locations decreased among SG but not control children. Six-month increases in daily moderate-to-vigorous physical activity did not significantly differ by group. Children might have altered the type of contexts where they engage in physical activity after moving to SG communities, yet more time may be necessary for these changes to impact overall physical activity.

  8. Investigation of the soluble metals in tissue as biological response pattern to environmental pollutants (Gammarus fossarum example).

    PubMed

    Filipović Marijić, Vlatka; Dragun, Zrinka; Sertić Perić, Mirela; Matoničkin Kepčija, Renata; Gulin, Vesna; Velki, Mirna; Ečimović, Sandra; Hackenberger, Branimir K; Erk, Marijana

    2016-07-01

    In the present study, Gammarus fossarum was used to investigate the bioaccumulation and toxic effects of aquatic pollutants in the real environmental conditions. The novelty of the study is the evaluation of soluble tissue metal concentrations in gammarids as indicators in early assessment of metal exposure. In the Sutla River, industrially/rurally/agriculturally influenced catchment in North-Western Croatia, physico-chemical water properties pointed to disturbed ecological status, which was reflected on population scale as more than 50 times lower gammarid density compared to the reference location, Črnomerec Stream. Significantly higher levels of soluble toxic metals (Al, As, Cd, Pb, Sb, Sn, Sr) were observed in gammarids from the Sutla River compared to the reference site and reflected the data on higher total dissolved metal levels in the river water at that site. The soluble metal estimates were supplemented with the common multibiomarker approach, which showed significant biological responses for decreased acetylcholinesterase activity and increased total soluble protein concentrations, confirming stressed environmental conditions for biota in the Sutla River. Biomarker of metal exposure, metallothionein, was not induced and therefore, toxic effect of metals was not confirmed on molecular level. Comparable between-site pattern of soluble toxic metals in gammarids and total dissolved metal levels in water suggests that prior to biomarker response and observed toxic impact, soluble metals in tissue might be used as early warning signs of metal impact in the aquatic environment and improve the assessment of water quality.

  9. Investigations into the organism level effects of the copper-induced oxidative stress response of Lemna gibba

    SciTech Connect

    Wall, V.D.; Klaine, S.J.

    1995-12-31

    The use of biochemical endpoints to indicate exposure to environmental toxicants is becoming an accepted technique to determine chemical bio-availability. However, these biochemical endpoints, or biomarkers, have not fulfilled their potential as indicators of sublethal stress when used in this capacity. Difficulties associated with using biochemical endpoints to assess stress arise in differentiating an ``abnormal`` stress response from a physiologically acceptable one and identifying sublethal stress in a biologically and ecologically significant manner. This research examines organism level effects of the copper-induced oxidative-stress response in Lemna gibba. The growth of Lemna gibba was significantly inhibited by aqueous copper concentrations greater than 0.05 ppm during a 10 day exposure. Although effects were dose dependent, the results indicated a conspicuous decrease in growth rates and increase in malformation and chlorosis at 0.5 ppm copper and higher. There were significantly elevated levels of lipid peroxidation products (expressed as thiobarbituric acid reactive species (TBARS)) at 0.1 ppm copper and higher. A decrease in growth rates without an increase in TBARS suggested a diversion of energy towards defensive mechanisms, primarily, superoxide dismutase, peroxidase, catalase and glutathione. These parameters were investigated and analyzed with respect to the organism-level effects (growth rates) of Lemna gibba. The utility and relevance of these sub-cellular parameters as indicators of chemical induced stress at the organism level will be discussed.

  10. Investigation of the soluble metals in tissue as biological response pattern to environmental pollutants (Gammarus fossarum example).

    PubMed

    Filipović Marijić, Vlatka; Dragun, Zrinka; Sertić Perić, Mirela; Matoničkin Kepčija, Renata; Gulin, Vesna; Velki, Mirna; Ečimović, Sandra; Hackenberger, Branimir K; Erk, Marijana

    2016-07-01

    In the present study, Gammarus fossarum was used to investigate the bioaccumulation and toxic effects of aquatic pollutants in the real environmental conditions. The novelty of the study is the evaluation of soluble tissue metal concentrations in gammarids as indicators in early assessment of metal exposure. In the Sutla River, industrially/rurally/agriculturally influenced catchment in North-Western Croatia, physico-chemical water properties pointed to disturbed ecological status, which was reflected on population scale as more than 50 times lower gammarid density compared to the reference location, Črnomerec Stream. Significantly higher levels of soluble toxic metals (Al, As, Cd, Pb, Sb, Sn, Sr) were observed in gammarids from the Sutla River compared to the reference site and reflected the data on higher total dissolved metal levels in the river water at that site. The soluble metal estimates were supplemented with the common multibiomarker approach, which showed significant biological responses for decreased acetylcholinesterase activity and increased total soluble protein concentrations, confirming stressed environmental conditions for biota in the Sutla River. Biomarker of metal exposure, metallothionein, was not induced and therefore, toxic effect of metals was not confirmed on molecular level. Comparable between-site pattern of soluble toxic metals in gammarids and total dissolved metal levels in water suggests that prior to biomarker response and observed toxic impact, soluble metals in tissue might be used as early warning signs of metal impact in the aquatic environment and improve the assessment of water quality. PMID:27060638

  11. Investigation of Stimulus-Response Compatibility Using a Startling Acoustic Stimulus

    ERIC Educational Resources Information Center

    Maslovat, Dana; Carlsen, Anthony N.; Franks, Ian M.

    2012-01-01

    We investigated the processes underlying stimulus-response compatibility by using a lateralized auditory stimulus in a simple and choice reaction time (RT) paradigm. Participants were asked to make either a left or right key lift in response to either a control (80dB) or startling (124dB) stimulus presented to either the left ear, right ear, or…

  12. Chemical ecology of fungi.

    PubMed

    Spiteller, Peter

    2015-07-01

    Fungi are widespread in nature and have conquered nearly every ecological niche. Fungi occur not only in terrestrial but also in freshwater and marine environments. Moreover, fungi are known as a rich source of secondary metabolites. Despite these facts, the ecological role of many of these metabolites is still unknown and the chemical ecology of fungi has not been investigated systematically so far. This review intends to present examples of the various chemical interactions of fungi with other fungi, plants, bacteria and animals and to give an overview of the current knowledge of fungal chemical ecology.

  13. Chemical ecology of fungi.

    PubMed

    Spiteller, Peter

    2015-07-01

    Fungi are widespread in nature and have conquered nearly every ecological niche. Fungi occur not only in terrestrial but also in freshwater and marine environments. Moreover, fungi are known as a rich source of secondary metabolites. Despite these facts, the ecological role of many of these metabolites is still unknown and the chemical ecology of fungi has not been investigated systematically so far. This review intends to present examples of the various chemical interactions of fungi with other fungi, plants, bacteria and animals and to give an overview of the current knowledge of fungal chemical ecology. PMID:26038303

  14. Distribution and mobility of heavy elements in floodplain agricultural soils along the Ibar River (Southern Serbia and Northern Kosovo). Chemometric investigation of pollutant sources and ecological risk assessment.

    PubMed

    Barać, Nemanja; Škrivanj, Sandra; Bukumirić, Zoran; Živojinović, Dragana; Manojlović, Dragan; Barać, Milan; Petrović, Rada; Ćorac, Aleksandar

    2016-05-01

    This work investigates the influence of a high-magnitude flood event on heavy elements (HEs) pollution and mobility in the agricultural soils along Ibar River in Southern Serbia and Northern Kosovo. The study area was one of the most important Pb/Zn industrial regions in Europe. Soil samples (n = 50) collected before and after the floods in May 2014 were subjected to the sequential extraction procedure proposed by the Community Bureau of Reference (BCR). The results indicated that the floods significantly increased not only the pseudo total concentrations of HEs in the soil but also their mobile and potentially bioavailable amounts. Moreover, higher concentrations (both pseudo total and potentially bioavailable) were found in the agricultural soils closer to the industrial hotspots. Principal component analysis and hierarchical cluster analysis successfully grouped the analyzed elements according to their anthropogenic or natural origin. The floods significantly increased the potential ecological risk of HEs associated with Pb/Zn industrial activities in the study area. The potential ecological risk of Cd after the floods was highest and should be of special concern. PMID:26822217

  15. Seeing the Wood for the Trees: Applying the dual-memory system model to investigate expert teachers' observational skills in natural ecological learning environments

    NASA Astrophysics Data System (ADS)

    Stolpe, Karin; Björklund, Lars

    2012-01-01

    This study aims to investigate two expert ecology teachers' ability to attend to essential details in a complex environment during a field excursion, as well as how they teach this ability to their students. In applying a cognitive dual-memory system model for learning, we also suggest a rationale for their behaviour. The model implies two separate memory systems: the implicit, non-conscious, non-declarative system and the explicit, conscious, declarative system. This model provided the starting point for the research design. However, it was revised from the empirical findings supported by new theoretical insights. The teachers were video and audio recorded during their excursion and interviewed in a stimulated recall setting afterwards. The data were qualitatively analysed using the dual-memory system model. The results show that the teachers used holistic pattern recognition in their own identification of natural objects. However, teachers' main strategy to teach this ability is to give the students explicit rules or specific characteristics. According to the dual-memory system model the holistic pattern recognition is processed in the implicit memory system as a non-conscious match with earlier experienced situations. We suggest that this implicit pattern matching serves as an explanation for teachers' ecological and teaching observational skills. Another function of the implicit memory system is its ability to control automatic behaviour and non-conscious decision-making. The teachers offer the students firsthand sensory experiences which provide a prerequisite for the formation of implicit memories that provides a foundation for expertise.

  16. Report on the remedial investigation of Bear Creek Valley at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee. Volume 6: Appendix G -- Baseline ecological risk assessment report

    SciTech Connect

    1996-09-01

    This Remedial Investigation (RI) Report characterizes the nature and extent of contamination, evaluates the fate and transport of contaminants, and assesses risk to human health and the environment resulting from waste disposal and other US Department of Energy (DOE) operations in Bear Creek Valley (BCV). BCV, which is located within the DOE Oak Ridge Reservation (ORR) encompasses multiple waste units containing hazardous and radioactive wastes arising from operations at the adjacent Oak Ridge Y-12 Plant. The primary waste units discussed in this RI Report are the S-3 Site, Oil Landfarm (OLF), Boneyard/Burnyard (BYBY), Sanitary Landfill 1 (SL 1), and Bear Creek Burial Grounds (BCBG). These waste units, plus the contaminated media resulting from environmental transport of the wastes from these units, are the subject of this RI. This BCV RI Report represents the first major step in the decision-making process for the BCV watershed. The RI results, in concert with the follow-on FS will form the basis for the Proposed Plan and Record of Decision for all BCV sites. This comprehensive decision document process will meet the objectives of the watershed approach for BCV. Appendix G contains ecological risks for fish, benthic invertebrates, soil invertebrates, plants, small mammals, deer, and predator/scavengers (hawks and fox). This risk assessment identified significant ecological risks from chemicals in water, sediment, soil, and shallow ground water. Metals and PCBs are the primary contaminants of concern.

  17. An eco-hydrological approach to predicting regional vegetation and groundwater response to ecological water convergence in dryland riparian ecosystems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To improve the management strategy of riparian restoration, better understanding of the dynamic of eco-hydrological system and its feedback between hydrological and ecological components are needed. The fully distributed eco-hydrological model coupled with a hydrology component was developed based o...

  18. Educational Responses to Newly Arrived Students in Sweden: Understanding the Structure and Influence of Post-Migration Ecology

    ERIC Educational Resources Information Center

    Nilsson, Jenny; Bunar, Nihad

    2016-01-01

    Education systems around the world have experienced a rise in the number of newly arrived students. This article explores the manner in which the Swedish education system responds to the diverse needs of these students. Using the concept of post-migration ecology, the authors outline and critically discuss the legal, organisational, and…

  19. A detailed investigation of flight buffeting response at subsonic and transonic speeds

    NASA Technical Reports Server (NTRS)

    Benepe, D. B.; Cunningham, A. M., Jr.; Dunmyer, W. D.

    1974-01-01

    The structural response to aerodynamic buffeting during moderate-to-high-g maneuvers was investigated. Dynamic response data measured during a flight loads program were analyzed to obtain power spectra and rms values of response for 19 sensors mounted on the test aircraft. In this paper, peaks in the power spectra of accelerations measured at the wing tips, center of gravity and pilot's seat, and wing vertical shear, bending moment and torsional moments are correlated with natural vibration modes. The amplitudes of response are compared to show effects of angle of attack, sensor type and location, Mach number, and altitude.

  20. Phase 1 Data Summary Report for the Clinch River Remedial Investigation: Health Risk and Ecological Risk Screening Assessment

    SciTech Connect

    Cook, R.B.

    1992-01-01

    The Clinch River Remedial Investigation (CRRI) is designed to address The transport, fate, and distribution of waterborne contaminants from the U.S. Department of Energy's (DOE's) Oak Ridge Reservation (ORR) and to assess potential risks to human health and the environment associated with these contaminants. The contaminants released since the early 1940s include a variety of radionuclides, metals, and organic compounds. Primary areas of investigation are Melton Hill Reservoir, the Clinch River from Melton Hill Dam to its confluence with the Tennessee River, Poplar Creek, and Watts Bar Reservoir. The receiving river-reservoir system encompasses 140 river miles in length and 44,000 acres in surface area and is used for municipal water supply, sport fishing, navigation, boating, swimming, tourism, and residential development. The contaminants identified in the Clinch River/Watts Bar Reservoir (CR/WBR) downstream of the ORR are those associated with the water, suspended particles, deposited sediments, aquatic organisms, and wildlife feeding on aquatic organisms. A phased remedial investigation of the CR/WBR system is underway to (1) define the nature and extent of the off-site contamination, (2) evaluate associated environmental and human health risks, and (3) preliminarily identify and evaluate potential remediation alternatives. The purpose of this report is to summarize the results of Phase 1 of the CRRI.

  1. Backyard Ecology.

    ERIC Educational Resources Information Center

    Elser, Monica; Musheno, Birgit; Saltz, Charlene

    2003-01-01

    Describes the Ecology Explorers, the community education component of Arizona State University's Central Arizona Phoenix Long-Term Ecological Research project, which offers teacher internship programs that link university researchers, K-12 teachers, and students in studying urban ecology. Explains that student neighborhoods are dynamic ecosystems…

  2. A new approach of Integrated Health Responses (IHR(s)) modeling for ecological risk/health assessments of an urban stream.

    PubMed

    Kim, Ja-Hyun; Yeom, Dong-Hyuk; An, Kwang-Guk

    2014-08-01

    The objective of this study was to evaluate the ecological health of an urban stream using Integrated Health Responses (IHRs). Water chemistry analysis, habitat health, and ecotoxicity tests were conducted in the stream along with analyses of molecular/biochemical, physiological biomarkers, and population-level responses in indicator species. Chemical stresses, measured as nutrient levels, ionic content and organic matter concentrations were significantly greater (p<0.01) at the downstream than the reference site (RF). The habitat health was largely impacted in the downstream reaches and had a negative relation with the land-use pattern of % urban area. Comet assay, 7-ethoxyresorufin-O-deethylase (EROD), acetylcholinesterase (AChE), and vitellogenin (VTG) were evaluated for low-level biomarker responses on DNA/physiological conditions of target species. The multi-metric fish model (Mm-F) was used to test the community-level response in relation to chemical and physical habitat stresses. The impaired responses of separate biomarker and bioindicator at the downstream sites occurred at all organizations from molecular/biochemical level to community level. Using all biomarkers/bioindicators, the star-plot model of IHRs was developed and then the integrative health/risk assessments were conducted in the urban stream. The reduced values of IHRs occurred in the downstream sites and the impacts were attributed to effluents from wastewater treatment plants (WTPs) and industrial complex. Ecological health impairments, thus, were evident in the urban reach, and reflected the long-term community responses as well as short-term responses of molecular biomarkers. The degradation of the urban stream was mainly due to a combined effect of chemical pollution and physical habitat modifications.

  3. Ecological responses to UV radiation: interactions between the biological effects of UV on plants and on associated organisms.

    PubMed

    Paul, Nigel D; Moore, Jason P; McPherson, Martin; Lambourne, Cathryn; Croft, Patricia; Heaton, Joanna C; Wargent, Jason J

    2012-08-01

    Solar ultraviolet (UV)-B radiation (280-315 nm) has a wide range of effects on terrestrial ecosystems, yet our understanding of how UV-B influences the complex interactions of plants with pest, pathogen and related microorganisms remains limited. Here, we report the results of a series of experiments in Lactuca sativa which aimed to characterize not only key plant responses to UV radiation in a field environment but also consequential effects for plant interactions with a sap-feeding insect, two model plant pathogens and phylloplane microorganism populations. Three spectrally modifying filters with contrasting UV transmissions were used to filter ambient sunlight, and when compared with our UV-inclusive filter, L. sativa plants grown in a zero UV-B environment showed significantly increased shoot fresh weight, reduced foliar pigment concentrations and suppressed population growth of green peach aphid (Myzus persicae). Plants grown under a filter which allowed partial transmission of UV-A radiation and negligible UV-B transmission showed increased density of leaf surface phylloplane microbes compared with the UV-inclusive treatment. Effects of UV treatment on the severity of two plant pathogens, Bremia lactucae and Botrytis cinerea, were complex as both the UV-inclusive and zero UV-B filters reduced the severity of pathogen persistence. These results are discussed with reference to known spectral responses of plants, insects and microorganisms, and contrasted with established fundamental responses of plants and other organisms to solar UV radiation, with particular emphasis on the need for future integration between different experimental approaches when investigating the effects of solar UV radiation. PMID:22150399

  4. Response of rocky shore communities to anthropogenic pressures in Albania (Mediterranean Sea): Ecological status assessment through the CARLIT method.

    PubMed

    Blanfuné, Aurélie; Boudouresque, Charles François; Verlaque, Marc; Beqiraj, Sajmir; Kashta, Lefter; Nasto, Ina; Ruci, Stela; Thibaut, Thierry

    2016-08-15

    The lower mid-littoral and shallow subtidal communities were studied in the district of Vlora (Albania), three years after the establishment of a Marine Protected Area, with particular attention to the long-lived species. The bioconstructions built in the mid-littoral zone by the calcified rhodobiont Lithophyllum byssoides were in poor condition and sometimes even dead. In contrast, the brown alga Cystoseira amentacea constituted lush stands. For assessing the ecological status of the studied area, the CARLIT method, based upon macroalgal communities, was applied. The observed range of ecological status was wide ('high' through 'bad') and was overall among the lowest assessed to date in the Mediterranean Sea. The occurrence of extensive sea-urchin barren-grounds, though not taken into consideration by the CARLIT index, confirmed the poor condition of large sectors of the study area. Overall, the CARLIT index is well correlated with anthropogenic pressures, as assessed by the LUSI index. PMID:27236230

  5. Predictive systems ecology.

    PubMed

    Evans, Matthew R; Bithell, Mike; Cornell, Stephen J; Dall, Sasha R X; Díaz, Sandra; Emmott, Stephen; Ernande, Bruno; Grimm, Volker; Hodgson, David J; Lewis, Simon L; Mace, Georgina M; Morecroft, Michael; Moustakas, Aristides; Murphy, Eugene; Newbold, Tim; Norris, K J; Petchey, Owen; Smith, Matthew; Travis, Justin M J; Benton, Tim G

    2013-11-22

    Human societies, and their well-being, depend to a significant extent on the state of the ecosystems that surround them. These ecosystems are changing rapidly usually in response to anthropogenic changes in the environment. To determine the likely impact of environmental change on ecosystems and the best ways to manage them, it would be desirable to be able to predict their future states. We present a proposal to develop the paradigm of predictive systems ecology, explicitly to understand and predict the properties and behaviour of ecological systems. We discuss the necessary and desirable features of predictive systems ecology models. There are places where predictive systems ecology is already being practised and we summarize a range of terrestrial and marine examples. Significant challenges remain but we suggest that ecology would benefit both as a scientific discipline and increase its impact in society if it were to embrace the need to become more predictive.

  6. Between Scylla and Charybdis: renegotiating resolution of the ‘obstetric dilemma’ in response to ecological change

    PubMed Central

    Wells, Jonathan C. K.

    2015-01-01

    Hominin evolution saw the emergence of two traits—bipedality and encephalization—that are fundamentally linked because the fetal head must pass through the maternal pelvis at birth, a scenario termed the ‘obstetric dilemma’. While adaptive explanations for bipedality and large brains address adult phenotype, it is brain and pelvic growth that are subject to the obstetric dilemma. Many contemporary populations experience substantial maternal and perinatal morbidity/mortality from obstructed labour, yet there is increasing recognition that the obstetric dilemma is not fixed and is affected by ecological change. Ecological trends may affect growth of the pelvis and offspring brain to different extents, while the two traits also differ by a generation in the timing of their exposure. Two key questions arise: how can the fit between the maternal pelvis and the offspring brain be ‘renegotiated’ as the environment changes, and what nutritional signals regulate this process? I argue that the potential for maternal size to change across generations precludes birthweight being under strong genetic influence. Instead, fetal growth tracks maternal phenotype, which buffers short-term ecological perturbations. Nevertheless, rapid changes in nutritional supply between generations can generate antagonistic influences on maternal and offspring traits, increasing the risk of obstructed labour. PMID:25602071

  7. Ecology of West Nile virus across four European countries: review of weather profiles, vector population dynamics and vector control response.

    PubMed

    Chaskopoulou, Alexandra; L'Ambert, Gregory; Petric, Dusan; Bellini, Romeo; Zgomba, Marija; Groen, Thomas A; Marrama, Laurence; Bicout, Dominique J

    2016-01-01

    West Nile virus (WNV) represents a serious burden to human and animal health because of its capacity to cause unforeseen and large epidemics. Until 2004, only lineage 1 and 3 WNV strains had been found in Europe. Lineage 2 strains were initially isolated in 2004 (Hungary) and in 2008 (Austria) and for the first time caused a major WNV epidemic in 2010 in Greece with 262 clinical human cases and 35 fatalities. Since then, WNV lineage 2 outbreaks have been reported in several European countries including Italy, Serbia and Greece. Understanding the interaction of ecological factors that affect WNV transmission is crucial for preventing or decreasing the impact of future epidemics. The synchronous co-occurrence of competent mosquito vectors, virus, bird reservoir hosts, and susceptible humans is necessary for the initiation and propagation of an epidemic. Weather is the key abiotic factor influencing the life-cycles of the mosquito vector, the virus, the reservoir hosts and the interactions between them. The purpose of this paper is to review and compare mosquito population dynamics, and weather conditions, in three ecologically different contexts (urban/semi-urban, rural/agricultural, natural) across four European countries (Italy, France, Serbia, Greece) with a history of WNV outbreaks. Local control strategies will be described as well. Improving our understanding of WNV ecology is a prerequisite step for appraising and optimizing vector control strategies in Europe with the ultimate goal to minimize the probability of WNV infection. PMID:27590848

  8. Ecology of West Nile virus across four European countries: review of weather profiles, vector population dynamics and vector control response.

    PubMed

    Chaskopoulou, Alexandra; L'Ambert, Gregory; Petric, Dusan; Bellini, Romeo; Zgomba, Marija; Groen, Thomas A; Marrama, Laurence; Bicout, Dominique J

    2016-01-01

    West Nile virus (WNV) represents a serious burden to human and animal health because of its capacity to cause unforeseen and large epidemics. Until 2004, only lineage 1 and 3 WNV strains had been found in Europe. Lineage 2 strains were initially isolated in 2004 (Hungary) and in 2008 (Austria) and for the first time caused a major WNV epidemic in 2010 in Greece with 262 clinical human cases and 35 fatalities. Since then, WNV lineage 2 outbreaks have been reported in several European countries including Italy, Serbia and Greece. Understanding the interaction of ecological factors that affect WNV transmission is crucial for preventing or decreasing the impact of future epidemics. The synchronous co-occurrence of competent mosquito vectors, virus, bird reservoir hosts, and susceptible humans is necessary for the initiation and propagation of an epidemic. Weather is the key abiotic factor influencing the life-cycles of the mosquito vector, the virus, the reservoir hosts and the interactions between them. The purpose of this paper is to review and compare mosquito population dynamics, and weather conditions, in three ecologically different contexts (urban/semi-urban, rural/agricultural, natural) across four European countries (Italy, France, Serbia, Greece) with a history of WNV outbreaks. Local control strategies will be described as well. Improving our understanding of WNV ecology is a prerequisite step for appraising and optimizing vector control strategies in Europe with the ultimate goal to minimize the probability of WNV infection.

  9. Large-scale dam removal in the northeast United States: documenting ecological responses to the Penobscot River Restoration Project

    NASA Astrophysics Data System (ADS)

    Collins, M. J.; Aponte Clarke, G.; Baeder, C.; McCaw, D.; Royte, J.; Saunders, R.; Sheehan, T.

    2012-12-01

    The Penobscot River Restoration Project aims to improve aquatic connectivity in New England's second largest watershed ( 22,000 km2) by removing the two lowermost, mainstem dams and bypassing a third dam on a principal tributary upstream. Project objectives include: restoring unobstructed access to the entire historic riverine range for five lower river diadromous species including Atlantic and shortnose sturgeon; significantly improving access to upstream habitat for six upper river diadromous species including Atlantic salmon; reconnecting trophic linkages between headwater areas and the Gulf of Maine; restoring fluvial processes to the former impoundments; improving recreational and Penobscot Nation cultural opportunities; and maintaining basin-wide hydropower output. The project is expected to have landscape-scale benefits and the need for a significant investment in long-term monitoring and evaluation to formally quantify ecosystem response has been recognized. A diverse group of federal, state, tribal, NGO, and academic partners has developed a long-term monitoring and evaluation program composed of nine studies that began in 2009. Including American Recovery and Reinvestment Act (ARRA) funding that leveraged partner contributions, we have invested nearly $2M to date in pre- and post-removal investigations that evaluate geomorphology/bed sediment, water quality, wetlands, and fisheries. Given the number of affected diadromous species and the diversity of their life histories, we have initiated six distinct, but related, fisheries investigations to document these expected changes: Atlantic salmon upstream and downstream passage efficiency using passive integrated transponder (PIT) and acoustic telemetry; fish community structure via an index of biotic integrity (IBI); total diadromous fish biomass through hydroacoustics; shortnose sturgeon spawning and habitat use via active and passive acoustic telemetry; and freshwater-marine food web interactions by

  10. Phase 1 data summary report for the Clinch River Remedial Investigation: Health risk and ecological risk screening assessment

    SciTech Connect

    Cook, R.B.; Adams, S.M.; Beauchamp, J.J.; Bevelhimer, M.S.; Blaylock, B.G.; Brandt, C.C.; Ford, C.J.; Frank, M.L.; Gentry, M.J.; Holladay, S.K.; Hook, L.A.; Levine, D.A.; Longman, R.C.; McGinn, C.W.; Skiles, J.L.; Suter, G.W.; Williams, L.F.

    1992-12-01

    The Clinch River Remedial Investigation (CRRI) is designed to address the transport, fate, and distribution of waterborne contaminants released from the US Department of Energy's (DOE's) Oak Ridge Reservation (ORR) and to assess potential risks to human health and the environment associated with these contaminants. The contaminants released since the early 1940s include a variety of radionuclides, metals, and organic compounds. The purpose of this report is to summarize the results of Phase 1 of the CRRI. Phase 1 was designed to (1) obtain high-quality data to confirm existing historical data for contaminant levels in fish, sediment, and water from the CR/WBR; (2) determine the in the range of contaminant concentrations present river-reservoir system; (3) identify specific contaminants of concern; and (4) establish the reference (background) concentrations for those contaminants.

  11. Integrating models to investigate critical phenological overlaps in complex ecological interactions: the mountain pine beetle-fungus symbiosis.

    PubMed

    Addison, Audrey; Powell, James A; Bentz, Barbara J; Six, Diana L

    2015-03-01

    The fates of individual species are often tied to synchronization of phenology, however, few methods have been developed for integrating phenological models involving linked species. In this paper, we focus on mountain pine beetle (MPB, Dendroctonus ponderosae) and its two obligate mutualistic fungi, Grosmannia clavigera and Ophiostoma montium. Growth rates of all three partners are driven by temperature, and their idiosyncratic responses affect interactions at important life stage junctures. One critical phase for MPB-fungus symbiosis occurs just before dispersal of teneral (new) adult beetles, when fungi are acquired and transported in specialized structures (mycangia). Before dispersal, fungi must capture sufficient spatial resources within the tree to ensure contact with teneral adults and get packed into mycangia. Mycangial packing occurs at an unknown time during teneral feeding. We adapt thermal models predicting fungal growth and beetle development to predict overlap between the competing fungi and MPB teneral adult feeding windows and emergence. We consider a spectrum of mycangial packing strategies and describe them in terms of explicit functions with unknown parameters. Rates of growth are fixed by laboratory data, the unknown parameters describing various packing strategies, as well as the degree to which mycangial growth is slowed in woody tissues as compared to agar, are determined by maximum likelihood and two years of field observations. At the field location used, the most likely fungus acquisition strategy for MPB was packing mycangia just prior to emergence. Estimated model parameters suggested large differences in the relative growth rates of the two fungi in trees at the study site, with the most likely model estimating that G. clavigera grew approximately twenty-five times faster than O. montium under the bark, which is completely unexpected in comparison with observed fungal growth on agar.

  12. Integrating models to investigate critical phenological overlaps in complex ecological interactions: the mountain pine beetle-fungus symbiosis.

    PubMed

    Addison, Audrey; Powell, James A; Bentz, Barbara J; Six, Diana L

    2015-03-01

    The fates of individual species are often tied to synchronization of phenology, however, few methods have been developed for integrating phenological models involving linked species. In this paper, we focus on mountain pine beetle (MPB, Dendroctonus ponderosae) and its two obligate mutualistic fungi, Grosmannia clavigera and Ophiostoma montium. Growth rates of all three partners are driven by temperature, and their idiosyncratic responses affect interactions at important life stage junctures. One critical phase for MPB-fungus symbiosis occurs just before dispersal of teneral (new) adult beetles, when fungi are acquired and transported in specialized structures (mycangia). Before dispersal, fungi must capture sufficient spatial resources within the tree to ensure contact with teneral adults and get packed into mycangia. Mycangial packing occurs at an unknown time during teneral feeding. We adapt thermal models predicting fungal growth and beetle development to predict overlap between the competing fungi and MPB teneral adult feeding windows and emergence. We consider a spectrum of mycangial packing strategies and describe them in terms of explicit functions with unknown parameters. Rates of growth are fixed by laboratory data, the unknown parameters describing various packing strategies, as well as the degree to which mycangial growth is slowed in woody tissues as compared to agar, are determined by maximum likelihood and two years of field observations. At the field location used, the most likely fungus acquisition strategy for MPB was packing mycangia just prior to emergence. Estimated model parameters suggested large differences in the relative growth rates of the two fungi in trees at the study site, with the most likely model estimating that G. clavigera grew approximately twenty-five times faster than O. montium under the bark, which is completely unexpected in comparison with observed fungal growth on agar. PMID:25556687

  13. A Field Study in Benin to Investigate the Role of Mosquitoes and Other Flying Insects in the Ecology of Mycobacterium ulcerans

    PubMed Central

    Zogo, Barnabas; Djenontin, Armel; Carolan, Kevin; Babonneau, Jeremy; Guegan, Jean-François; Eyangoh, Sara; Marion, Estelle

    2015-01-01

    Background Buruli ulcer, the third mycobacterial disease after tuberculosis and leprosy, is caused by the environmental mycobacterium M. ulcerans. There is at present no clear understanding of the exact mode(s) of transmission of M. ulcerans. Populations affected by Buruli ulcer are those living close to humid and swampy zones. The disease is associated with the creation or the extension of swampy areas, such as construction of dams or lakes for the development of agriculture. Currently, it is supposed that insects (water bugs and mosquitoes) are host and vector of M. ulcerans. The role of water bugs was clearly demonstrated by several experimental and environmental studies. However, no definitive conclusion can yet be drawn concerning the precise importance of this route of transmission. Concerning the mosquitoes, DNA was detected only in mosquitoes collected in Australia, and their role as host/vector was never studied by experimental approaches. Surprisingly, no specific study was conducted in Africa. In this context, the objective of this study was to investigate the role of mosquitoes (larvae and adults) and other flying insects in ecology of M. ulcerans. This study was conducted in a highly endemic area of Benin. Methodology/Principal Findings Mosquitoes (adults and larvae) were collected over one year, in Buruli ulcer endemic in Benin. In parallel, to monitor the presence of M. ulcerans in environment, aquatic insects were sampled. QPCR was used to detected M. ulcerans DNA. DNA of M. ulcerans was detected in around 8.7% of aquatic insects but never in mosquitoes (larvae or adults) or in other flying insects. Conclusion/Significance This study suggested that the mosquitoes don't play a pivotal role in the ecology and transmission of M. ulcerans in the studied endemic areas. However, the role of mosquitoes cannot be excluded and, we can reasonably suppose that several routes of transmission of M. ulcerans are possible through the world. PMID:26196901

  14. Anuran larval developmental plasticity and survival in response to variable salinity of ecologically relevant timing and magnitude.

    PubMed

    Kearney, Brian D; Pell, Rebecca J; Byrne, Phillip G; Reina, Richard D

    2014-12-01

    Salinity in affected freshwater ecosystems fluctuates with seasonal rainfall, tidal flux, rates of evaporation, chemical runoff and the influence of secondary salinization. Environmental stressors such as salinity can have lasting effects on anuran development, yet little is known about the effects of fluctuating salinity on tadpole ontogeny or the effects of differing magnitudes of salinity exposure, as would occur in natural wetland systems. We examined how salinity fluctuations affected survival, growth and development of Litoria ewingii by exposing tadpoles to a range of salinity concentrations (5.6-10.85 ppt) at three different stages of development (hind limb-bud formation; toe differentiation and forearm development). We also investigated the plasticity of tadpole growth rates in response to non-lethal, transient salinity influxes, specifically examining the capacity for compensatory growth and its relationship to the timing, magnitude or frequency of salinity exposure. Our results show that later-stage tadpoles are more tolerant to elevated salinity than those exposed at a younger age, and that exposure to high salinity later in life suppresses the potential for compensatory growth. Tadpoles exposed to transient low salinity lost less mass during metamorphosis than animals in constant salinity treatments, indicating a possible alternate to compensatory growth. Exposure to near-lethal salinities early in development did not alter tadpole responses to subsequent salinity stress. Our results provide some of the first evidence that both the timing and magnitude of transient environmental stressors can have an effect on anuran development and developmental trade-offs in a stressful environment.

  15. Investigating the effectiveness of response strategies for vulnerabilities to corruption in the chinese public construction sector.

    PubMed

    Shan, Ming; Chan, Albert P C; Le, Yun; Hu, Yi

    2015-06-01

    Response strategy is a key for preventing widespread corruption vulnerabilities in the public construction sector. Although several studies have been devoted to this area, the effectiveness of response strategies has seldom been evaluated in China. This study aims to fill this gap by investigating the effectiveness of response strategies for corruption vulnerabilities through a survey in the Chinese public construction sector. Survey data obtained from selected experts involved in the Chinese public construction sector were analyzed by factor analysis and partial least squares-structural equation modeling. Analysis results showed that four response strategies of leadership, rules and regulations, training, and sanctions, only achieved an acceptable level in preventing corruption vulnerabilities in the Chinese public construction sector. This study contributes to knowledge by improving the understanding of the effectiveness of response strategies for corruption vulnerabilities in the public construction sector of developing countries. PMID:24894336

  16. Investigating the effectiveness of response strategies for vulnerabilities to corruption in the chinese public construction sector.

    PubMed

    Shan, Ming; Chan, Albert P C; Le, Yun; Hu, Yi

    2015-06-01

    Response strategy is a key for preventing widespread corruption vulnerabilities in the public construction sector. Although several studies have been devoted to this area, the effectiveness of response strategies has seldom been evaluated in China. This study aims to fill this gap by investigating the effectiveness of response strategies for corruption vulnerabilities through a survey in the Chinese public construction sector. Survey data obtained from selected experts involved in the Chinese public construction sector were analyzed by factor analysis and partial least squares-structural equation modeling. Analysis results showed that four response strategies of leadership, rules and regulations, training, and sanctions, only achieved an acceptable level in preventing corruption vulnerabilities in the Chinese public construction sector. This study contributes to knowledge by improving the understanding of the effectiveness of response strategies for corruption vulnerabilities in the public construction sector of developing countries.

  17. An experimental investigation of free-tip response to a jet

    NASA Technical Reports Server (NTRS)

    Young, L. A.

    1986-01-01

    The aerodynamic response of passively oscillating tips appended to a model helicopter rotor was investigated during a whirl test. Tip responsiveness was found to meet free-tip rotor requirements. Experimental and analytical estimates of the free-tip aerodynamic spring, mechanical spring, and aerodynamic damping were calculated and compared. The free tips were analytically demonstrated to be operating outside the tip resonant response region at full-scale tip speeds. Further, tip resonance was shown to be independent of tip speed, given the assumption that the tip forcing frequency is linearly dependent upon the rotor rotational speed.

  18. Is outcome responsibility at work emotionally exhausting? Investigating employee proactivity as a moderator.

    PubMed

    Schmitt, Antje; Den Hartog, Deanne N; Belschak, Frank D

    2015-10-01

    This study investigates the relationship between outcome responsibility and employees' well-being in terms of emotional exhaustion. Outcome responsibility is a job demand implying that employees' decisions at work have high material and/or nonmaterial consequences. Previous research indicates that outcome responsibility can have both positive and negative effects on employee well-being. Based on the person-job fit approach we hypothesize that whether or not outcome responsibility is positively or negatively related to emotional exhaustion depends on whether employees' behavioral style fits with this job demand. We investigate the role of proactive behavior as a personal resource that fits with high responsibility. We test our hypothesis in a multisource study among 138 employee-colleague dyads. Results of hierarchical moderated regression analysis reveal that peer-rated proactive behavior moderates the relationship between outcome responsibility and emotional exhaustion, such that the relationship is negative for employees showing high and nonsignificant for employees showing low proactivity. This finding holds also when controlling for trait positive and negative affect. The current study contributes to previous research on job design, proactivity, and occupational well-being and offers practical implications in terms of selection and training of employees for jobs high in outcome responsibility. PMID:25798719

  19. Is outcome responsibility at work emotionally exhausting? Investigating employee proactivity as a moderator.

    PubMed

    Schmitt, Antje; Den Hartog, Deanne N; Belschak, Frank D

    2015-10-01

    This study investigates the relationship between outcome responsibility and employees' well-being in terms of emotional exhaustion. Outcome responsibility is a job demand implying that employees' decisions at work have high material and/or nonmaterial consequences. Previous research indicates that outcome responsibility can have both positive and negative effects on employee well-being. Based on the person-job fit approach we hypothesize that whether or not outcome responsibility is positively or negatively related to emotional exhaustion depends on whether employees' behavioral style fits with this job demand. We investigate the role of proactive behavior as a personal resource that fits with high responsibility. We test our hypothesis in a multisource study among 138 employee-colleague dyads. Results of hierarchical moderated regression analysis reveal that peer-rated proactive behavior moderates the relationship between outcome responsibility and emotional exhaustion, such that the relationship is negative for employees showing high and nonsignificant for employees showing low proactivity. This finding holds also when controlling for trait positive and negative affect. The current study contributes to previous research on job design, proactivity, and occupational well-being and offers practical implications in terms of selection and training of employees for jobs high in outcome responsibility.

  20. [Comparative investigation of locust's phototactic visual spectrum effect and phototactic response to spectral illumination].

    PubMed

    Liu, Qi-Hang; Zhou, Qiang

    2014-07-01

    To provide theoretical support for determining locust's phototactic spectrum, and explore locust's phototactic mechanism stimulated by light, utilizing AvaSpec fiber-optic spectrometer system and AvaLight-DHS, the investigation of locust's phototactic visual spectrum effect after light energy stimulated locust's vision system was carried out and on this basis, utilizing the investigated device of locust's phototactic response to spectral illumination, the discrepancy of locust's phototactic response to spectral illumination was certificated comparatively. The results show that the degree of locust's vision system absorbing the single spectrum photon of 430, 545 and 610 nm is significant and there exists difference, and the behavioral response to orange, violet, green, and blue spectral light has the difference in selective sensitivity, with the intensity of response to violet light being the strongest. The degree of response to orange light is the maximum, simultaneously, locust's vision system absorbing spectral photon energy has selective difference and requirement of illumination time, moreover, the sensitive degree of locust's visual system to spectrum and the strength of the lighting energy, influencing locust's phototactic response degree, and the micro-response of locust's phototactic vision physiology, led by the photoelectric effect of locust absorbing sensitive photon and converting photon energy, is the reason for locust's phototactic orientation response. In addition, locust's phototactic visual spectrum effect, only when the biological photoelectric effect of locust's visual system is stimulated by spectral illumination, can present the sensitivity of the spectral absorption effect, so, using the stronger ultraviolet stimulation characteristic of violet light, the different sensitive stimulation of orange, green, blue spectral light on locust's phototactic vision, and combining orange, violet, green, blue spectral light field mechanism reasonably, can

  1. An Investigation of Science Educators' View of Roles and Responsibilities for Climate Change Education

    ERIC Educational Resources Information Center

    McGinnis, J. Randy; McDonald, Chris; Hestness, Emily; Breslyn, Wayne

    2016-01-01

    This exploratory study investigates what science educators from differing groups (outside of higher education--informal and formal (K-12) and inside of higher education--content and pedagogy experts) believe are the roles and responsibilities (and what actions these might involve) in climate change education for: 1) their group of educators, and…

  2. 14 CFR 431.45 - Mishap investigation plan and emergency response plan.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... incident, or a mishap that involves a fatality or serious injury (as defined in 49 CFR 830.2); (2... a mishap that does not involve a fatality or serious injury, as defined in 49 CFR 830.2; and (3... response plan. An applicant shall submit a mishap investigation plan (MIP) containing the...

  3. 14 CFR 431.45 - Mishap investigation plan and emergency response plan.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... incident, or a mishap that involves a fatality or serious injury (as defined in 49 CFR 830.2); (2... a mishap that does not involve a fatality or serious injury, as defined in 49 CFR 830.2; and (3... response plan. An applicant shall submit a mishap investigation plan (MIP) containing the...

  4. 14 CFR 431.45 - Mishap investigation plan and emergency response plan.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... incident, or a mishap that involves a fatality or serious injury (as defined in 49 CFR 830.2); (2... a mishap that does not involve a fatality or serious injury, as defined in 49 CFR 830.2; and (3... response plan. An applicant shall submit a mishap investigation plan (MIP) containing the...

  5. 14 CFR 431.45 - Mishap investigation plan and emergency response plan.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Mishap investigation plan and emergency response plan. 431.45 Section 431.45 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL... incident, or a mishap that involves a fatality or serious injury (as defined in 49 CFR 830.2);...

  6. Investigating Nigerian Primary School Teachers' Preparedness to Adopt Personal Response System in ESL Classroom

    ERIC Educational Resources Information Center

    Agbatogun, Alaba Olaoluwakotansibe

    2012-01-01

    This study investigated the extent to which computer literacy dimensions (computer general knowledge, documents and documentations, communication and surfing as well as data inquiry), computer use and academic qualification as independent variables predicted primary school teachers' attitude towards the integration of Personal Response System in…

  7. Response to Intervention: An Investigation of Training, Perceptions, and Fidelity of Implementation

    ERIC Educational Resources Information Center

    Carpenter, Karen L.

    2013-01-01

    The authors investigated the extent to which the amount of training in Response to Intervention (RtI) impacts staff members' perceptions of RtI, how staff members' perceptions of RtI relate to their fidelity of implementation, and to what degree staff members' involvement in training influences their fidelity of implementation. A convenience…

  8. Preparing Culturally Responsive Literacy Teachers: Investigations of Whiteness in a Literacy Methods Course

    ERIC Educational Resources Information Center

    Royster, Kelly Berghoff

    2013-01-01

    Teacher education programs across the United States must prepare teachers who have the content area knowledge, pedagogical expertise, and cultural competence needed to teach an increasingly diverse student population. One consistent suggestion for programs committed to preparing culturally responsive teachers is to incorporate investigations of…

  9. An ecological approach to promoting population mental health and well-being--a response to the challenge of climate change.

    PubMed

    Nurse, Jo; Basher, Damian; Bone, Angie; Bird, William

    2010-01-01

    Climate change can be viewed as human-induced change to climate and depletion of natural systems. It potentially the biggest global health threat of the 21st century. It is predicted to have wide-ranging impacts upon human mental health and well-being, through changes and challenges to people's environment, socioeconomic structures and physical security. Even the most conservative estimates of the health impacts are extremely alarming. Increasingly, the causes of poor human health and environmental damage are related. This implies that there are common solutions. For example, there are co-benefits to human health and biodiversity from mitigating and adapting to climate change (e.g. promoting active transport and reducing car use reduces CO2 emissions, benefits our environment and reduces morbidity and mortality associated with a sedentary lifestyle). This article outlines how climate change impacts upon mental health and well-being. It introduces ecological concepts, applies these to public health and outlines their implications in transforming the way that we prioritize and deliver public health in order to promote both environmental and human health. Evidence, from psychology and neuroscience, suggests that the perception of being disconnected from our inner selves, from each other and from our environment has contributed to poor mental and physical health. We argue that we must transform the way we understand mental health and well-being and integrate it into action against climate change. We describe a Public Health Framework for Developing Well-Being, based on the principles of ecological public health.

  10. ``Yo soy indígena'': identifying and using traditional ecological knowledge (TEK) to make the teaching of science culturally responsive for Maya girls

    NASA Astrophysics Data System (ADS)

    Hamlin, Maria L.

    2013-12-01

    This study examines how traditional ecological knowledge—TEK—can be identified and utilized to create culturally responsive science learning opportunities for Maya girls from a community in the Guatemalan highlands. Maya girls are situated in a complex socio-historical and political context rooted in racism and sexism. This study contextualizes the current situation of Maya women and girls in Guatemala and emphasizes the important need for educators to create science-learning opportunities that are culturally congruent. The author posits that when considering how to make the teaching and learning of science culturally responsive for Maya girls, educators must begin with the scientific knowledge inherent within Maya communities. Indigenous communities have a wealth of TEK that can be used to contextualize science curricula that can be purposely designed to meet the nuanced cultural needs of traditional Maya girls within and outside Guatemala.

  11. Integration of aquatic fate and ecological responses to linear alkyl benzene sulfonate (LAS) in model stream ecosystems.

    PubMed

    Belanger, S E; Bowling, J W; Lee, D M; LeBlanc, E M; Kerr, K M; McAvoy, D C; Christman, S C; Davidson, D H

    2002-06-01

    An integrated model stream ecosystem fate and effect study of dodecyl linear alkylbenzene sulfonate (C(12)LAS) was performed in the summer and fall of 1996. The study addressed responses of periphytic microbes, immature benthic fauna including abundance, drift, and emergence of adult insects in a 56-day exposure. Exposures ranged from 126 to 2978 microg/L and were continuously presented in a single-pass, flow-through test system. Microbial heterotrophs acclimated to C(12)LAS exposure quickly (14 days) and biodegraded C(12)LAS at all concentrations. Blue-green algae responded by increasing in abundance with increasing C(12)LAS concentration. Invertebrates responded by increased drift and reduced benthic abundances at concentrations exceeding 293 microg/L. Emergence at 927 microg/L also declined relative to the control. Adverse responses for mayflies and chironomids were indicated using univariate statistical techniques. Multivariate techniques indicated these taxa plus mollusks, aquatic worms, caddisflies, and stoneflies were impaired at some concentrations. Bioavailability of C(12)LAS was investigated in streams as a function of the total suspended solid load in the water column driven by local weather and watershed patterns. A continuous bioavailability model indicated exposure was reduced by an average of 8.5+/-8.9%. A model ecosystem no-observed-effect concentration (NOEC) was concluded to be 293 microg/L based on measured water column exposure and adjusted to 268 microg/L by the bioavailability model. A literature review of 13 available model ecosystem studies was conducted and NOEC conclusions were adjusted by a structure-activity relationship to a dodecyl chain length (sulfophenyl position and distribution being ignored due to lack of information in the reviewed studies). Lentic studies (n=7) were found to have higher NOECs than lotic studies (n=6) and were more variable. Mean NOECs+/-SD for all studies, lentic studies only, and lotic studies only were 3320

  12. Colony-specific investigations reveal highly variable responses among individual corals to ocean acidification and warming.

    PubMed

    Kavousi, Javid; Reimer, James Davis; Tanaka, Yasuaki; Nakamura, Takashi

    2015-08-01

    As anthropogenic climate change is an ongoing concern, scientific investigations on its impacts on coral reefs are increasing. Although impacts of combined ocean acidification (OA) and temperature stress (T) on reef-building scleractinian corals have been studied at the genus, species and population levels, there are little data available on how individual corals respond to combined OA and anomalous temperatures. In this study, we exposed individual colonies of Acropora digitifera, Montipora digitata and Porites cylindrica to four pCO2-temperature treatments including 400 μatm-28 °C, 400 μatm-31 °C, 1000 μatm-28 °C and 1000 μatm-31 °C for 26 days. Physiological parameters including calcification, protein content, maximum photosynthetic efficiency, Symbiodinium density, and chlorophyll content along with Symbiodinium type of each colony were examined. Along with intercolonial responses, responses of individual colonies versus pooled data to the treatments were investigated. The main results were: 1) responses to either OA or T or their combination were different between individual colonies when considering physiological functions; 2) tolerance to either OA or T was not synonymous with tolerance to the other parameter; 3) tolerance to both OA and T did not necessarily lead to tolerance of OA and T combined (OAT) at the same time; 4) OAT had negative, positive or no impacts on physiological functions of coral colonies; and 5) pooled data were not representative of responses of all individual colonies. Indeed, the pooled data obscured actual responses of individual colonies or presented a response that was not observed in any individual. From the results of this study we recommend improving experimental designs of studies investigating physiological responses of corals to climate change by complementing them with colony-specific examinations.

  13. Colony-specific investigations reveal highly variable responses among individual corals to ocean acidification and warming.

    PubMed

    Kavousi, Javid; Reimer, James Davis; Tanaka, Yasuaki; Nakamura, Takashi

    2015-08-01

    As anthropogenic climate change is an ongoing concern, scientific investigations on its impacts on coral reefs are increasing. Although impacts of combined ocean acidification (OA) and temperature stress (T) on reef-building scleractinian corals have been studied at the genus, species and population levels, there are little data available on how individual corals respond to combined OA and anomalous temperatures. In this study, we exposed individual colonies of Acropora digitifera, Montipora digitata and Porites cylindrica to four pCO2-temperature treatments including 400 μatm-28 °C, 400 μatm-31 °C, 1000 μatm-28 °C and 1000 μatm-31 °C for 26 days. Physiological parameters including calcification, protein content, maximum photosynthetic efficiency, Symbiodinium density, and chlorophyll content along with Symbiodinium type of each colony were examined. Along with intercolonial responses, responses of individual colonies versus pooled data to the treatments were investigated. The main results were: 1) responses to either OA or T or their combination were different between individual colonies when considering physiological functions; 2) tolerance to either OA or T was not synonymous with tolerance to the other parameter; 3) tolerance to both OA and T did not necessarily lead to tolerance of OA and T combined (OAT) at the same time; 4) OAT had negative, positive or no impacts on physiological functions of coral colonies; and 5) pooled data were not representative of responses of all individual colonies. Indeed, the pooled data obscured actual responses of individual colonies or presented a response that was not observed in any individual. From the results of this study we recommend improving experimental designs of studies investigating physiological responses of corals to climate change by complementing them with colony-specific examinations. PMID:26009841

  14. Thermal onset of cellular and endocrine stress responses correspond to ecological limits in brook trout, an iconic cold-water fish

    PubMed Central

    Chadwick, Joseph G.; Nislow, Keith H.; McCormick, Stephen D.

    2015-01-01

    Climate change is predicted to change the distribution and abundance of species, yet underlying physiological mechanisms are complex and methods for detecting populations at risk from rising temperature are poorly developed. There is increasing interest in using physiological mediators of the stress response as indicators of individual and population-level response to environmental stressors. Here, we use laboratory experiments to show that the temperature thresholds in brook trout (Salvelinus fontinalis) for increased gill heat shock protein-70 (20.7°C) and plasma glucose (21.2°C) are similar to their proposed thermal ecological limit of 21.0°C. Field assays demonstrated increased plasma glucose, cortisol and heat shock protein-70 concentrations at field sites where mean daily temperature exceeded 21.0°C. Furthermore, population densities of brook trout were lowest at field sites where temperatures were warm enough to induce a stress response, and a co-occurring species with a higher thermal tolerance showed no evidence of physiological stress at a warm site. The congruence of stress responses and proposed thermal limits supports the use of these thresholds in models of changes in trout distribution under climate change scenarios and suggests that the induction of the stress response by elevated temperature may play a key role in driving the distribution of species. PMID:27293702

  15. Thermal onset of cellular and endocrine stress responses correspond to ecological limits in brook trout, an iconic cold-water fish

    USGS Publications Warehouse

    Chadwick, Joseph G; Nislow, Kieth H; McCormick, Stephen

    2015-01-01

    Climate change is predicted to change the distribution and abundance of species, yet underlying physiological mechanisms are complex and methods for detecting populations at risk from rising temperature are poorly developed. There is increasing interest in using physiological mediators of the stress response as indicators of individual and population-level response to environmental stressors. Here, we use laboratory experiments to show that the temperature thresholds in brook trout (Salvelinus fontinalis) for increased gill heat shock protein-70 (20.7°C) and plasma glucose (21.2°C) are similar to their proposed thermal ecological limit of 21.0°C. Field assays demonstrated increased plasma glucose, cortisol and heat shock protein-70 concentrations at field sites where mean daily temperature exceeded 21.0°C. Furthermore, population densities of brook trout were lowest at field sites where temperatures were warm enough to induce a stress response, and a co-occurring species with a higher thermal tolerance showed no evidence of physiological stress at a warm site. The congruence of stress responses and proposed thermal limits supports the use of these thresholds in models of changes in trout distribution under climate change scenarios and suggests that the induction of the stress response by elevated temperature may play a key role in driving the distribution of species.

  16. [Several problems in ecological security assessment research].

    PubMed

    Wang, Genxu; Cheng, Guodong; Qian, Ju

    2003-09-01

    Ecological security assessment is the identification and judgment of ecosystem completeness and sustainable ability to maintain ecosystem health under all kinds of risks, the core contents of which are ecological risk assessment and ecological health assessment. Ecological risk identification and ecological vulnerability are the composing elements of ecological risk assessment, while ecological health includes three aspects, i.e., ecological completeness, ecosystem vigor, and ecosystem resilience. In the studies of ecological security assessment, the rational combination of ecological risk and ecological health, and the establishment of integrated measure index system based on confirming spatial scale are needed. At present, risk factor identification index, exposure analysis index, and influence (response) analysis index are the broader construction systems of ecological risk index. Nevertheless, on the basis of the classification of EDI, REI and IRI, the method of superimposing exposure analysis index may be the development direction of establishing index system in the future. Among the methods of quantificational assessment, exposure-response analysis was one of the most extensive method used at present, but ecological model method to assess different-scale ecological security will be the main development field, and focused on the security of ecological processes in the future. Ecological security assessment must be intergraded with ecological prediction, security guarantee and management. PMID:14733019

  17. Spatially Explicit Landscape-Level Ecological Risks Induced by Land Use and Land Cover Change in a National Ecologically Representative Region in China.

    PubMed

    Gong, Jian; Yang, Jianxin; Tang, Wenwu

    2015-11-01

    Land use and land cover change is driven by multiple influential factors from environmental and social dimensions in a land system. Land use practices of human decision-makers modify the landscape of the land system, possibly leading to landscape fragmentation, biodiversity loss, or environmental pollution-severe environmental or ecological impacts. While landscape-level ecological risk assessment supports the evaluation of these impacts, investigations on how these ecological risks induced by land use practices change over space and time in response to alternative policy intervention remain inadequate. In this article, we conducted spatially explicit landscape ecological risk analysis in Ezhou City, China. Our study area is a national ecologically representative region experiencing drastic land use and land cover change, and is regulated by multiple policies represented by farmland protection, ecological conservation, and urban development. We employed landscape metrics to consider the influence of potential landscape-level disturbance for the evaluation of landscape ecological risks. Using spatiotemporal simulation, we designed scenarios to examine spatiotemporal patterns in landscape ecological risks in response to policy intervention. Our study demonstrated that spatially explicit landscape ecological risk analysis combined with simulation-driven scenario analysis is of particular importance for guiding the sustainable development of ecologically vulnerable land systems. PMID:26569270

  18. Spatially Explicit Landscape-Level Ecological Risks Induced by Land Use and Land Cover Change in a National Ecologically Representative Region in China

    PubMed Central

    Gong, Jian; Yang, Jianxin; Tang, Wenwu

    2015-01-01

    Land use and land cover change is driven by multiple influential factors from environmental and social dimensions in a land system. Land use practices of human decision-makers modify the landscape of the land system, possibly leading to landscape fragmentation, biodiversity loss, or environmental pollution—severe environmental or ecological impacts. While landscape-level ecological risk assessment supports the evaluation of these impacts, investigations on how these ecological risks induced by land use practices change over space and time in response to alternative policy intervention remain inadequate. In this article, we conducted spatially explicit landscape ecological risk analysis in Ezhou City, China. Our study area is a national ecologically representative region experiencing drastic land use and land cover change, and is regulated by multiple policies represented by farmland protection, ecological conservation, and urban development. We employed landscape metrics to consider the influence of potential landscape-level disturbance for the evaluation of landscape ecological risks. Using spatiotemporal simulation, we designed scenarios to examine spatiotemporal patterns in landscape ecological risks in response to policy intervention. Our study demonstrated that spatially explicit landscape ecological risk analysis combined with simulation-driven scenario analysis is of particular importance for guiding the sustainable development of ecologically vulnerable land systems. PMID:26569270

  19. Spatially Explicit Landscape-Level Ecological Risks Induced by Land Use and Land Cover Change in a National Ecologically Representative Region in China.

    PubMed

    Gong, Jian; Yang, Jianxin; Tang, Wenwu

    2015-11-09

    Land use and land cover change is driven by multiple influential factors from environmental and social dimensions in a land system. Land use practices of human decision-makers modify the landscape of the land system, possibly leading to landscape fragmentation, biodiversity loss, or environmental pollution-severe environmental or ecological impacts. While landscape-level ecological risk assessment supports the evaluation of these impacts, investigations on how these ecological risks induced by land use practices change over space and time in response to alternative policy intervention remain inadequate. In this article, we conducted spatially explicit landscape ecological risk analysis in Ezhou City, China. Our study area is a national ecologically representative region experiencing drastic land use and land cover change, and is regulated by multiple policies represented by farmland protection, ecological conservation, and urban development. We employed landscape metrics to consider the influence of potential landscape-level disturbance for the evaluation of landscape ecological risks. Using spatiotemporal simulation, we designed scenarios to examine spatiotemporal patterns in landscape ecological risks in response to policy intervention. Our study demonstrated that spatially explicit landscape ecological risk analysis combined with simulation-driven scenario analysis is of particular importance for guiding the sustainable development of ecologically vulnerable land systems.

  20. Animal Models for Investigating the Central Control of the Mammalian Diving Response

    PubMed Central

    McCulloch, Paul Frederick

    2012-01-01

    Pioneering studies by Per Scholander indicated that the diving response consists of reflexly induced apnea, bradycardia and an alteration of blood flow that maintains perfusion of the heart and brain. More recently field physiological studies have shown that many marine animals can adjust cardiorespiratory aspects of their diving response depending upon the behavioral situation. This could suggest that the very labile heart rate during diving is under direct cortical control. However, the final control of autonomic nervous system functioning resides within the brainstem and not the cortex. Many physiologists regard the brain as a “black box” where important neuronal functioning occurs, but the complexity of such functioning leaves systematic investigation a daunting task. As a consequence the central control of the diving response has been under-investigated. Thus, to further advance the field of diving physiology by understanding its central neuronal control, it would be first necessary to understand the reflex circuitry that exists within the brainstem of diving animals. To do this will require an appropriate animal model. In this review, two animals, the muskrat and rat, will be offered as animal models to investigate the central aspects of the diving response. Firstly, although these rodents are not marine animals, natural histories indicate that both animals can and do exploit aquatic environments. Secondly, physiological recordings during natural and simulated diving indicate that both animals possess the same basic physiological responses to underwater submersion that occur in marine animals. Thirdly, the size and ease of housing of both animals makes them attractive laboratory research animals. Finally, the enormous amount of scientific literature regarding rodent brainstem autonomic control mechanisms, and the availability of brain atlases, makes these animals ideal choices to study the central control of the mammalian diving response. PMID:22661956

  1. Ecological Consultancy

    ERIC Educational Resources Information Center

    Wilson, Scott McG.; Tattersfield, Peter

    2004-01-01

    This is the first of a new regular feature on careers, designed to provide those who teach biology with some inspiration when advising their students. In this issue, two consultant ecologists explain how their career paths developed. It is a misconception that there are few jobs in ecology. Over the past 20 or 30 years ecological consultancy has…

  2. Soil Ecology

    NASA Astrophysics Data System (ADS)

    Killham, Ken

    1994-04-01

    Soil Ecology is designed to meet the increasing challenge faced by today's environmental scientists, ecologists, agriculturalists, and biotechnologists for an integrated approach to soil ecology. It emphasizes the interrelations among plants, animals, and microbes, by first establishing the fundamental physical and chemical properties of the soil habitat and then functionally characterizing the major components of the soil biota and some of their most important interactions. The fundamental principles underpinning soil ecology are established and this then enables an integrated approach to explore and understand the processes of soil nutrient (carbon, nitrogen, and phosphorus) cycling and the ecology of extreme soil conditions such as soil-water stress. Two of the most topical aspects of applied soil ecology are then selected. First, the ecology of soil pollution is examined, focusing on acid deposition and radionuclide pollution. Second, manipulation of soil ecology through biotechnology is discussed, illustrating the use of pesticides and microbial inocula in soils and pointing toward the future by considering the impact of genetically modified inocula on soil ecology.

  3. Ecology of estuaries

    SciTech Connect

    Kennish, M.J.

    1986-01-01

    This book is a summary of information available on estuarine ecology, that reviews concepts and problems of estuaries and assesses the value of these coastal systems. It investigates such topics as water circulation and mixing, trace elements, nutrients, organic matter, and sedimentary processes, with reviews on more than two decades of intense study. Chapters reflect contributions from a variety of interdisciplinary sciences including botany, chemistry, ecology, geology, physics, and zoology.

  4. Pilot investigation of the utility of a student response system in medical student lectures.

    PubMed

    Roy, K H

    1996-03-01

    An evaluation of a student response system was undertaken to investigate its effect on lectures. Use of the system in lectures at the University of Wales College of Medicine (UWCM) was observed for a trial period. Analyses of these observations, and the opinions of lecturers and students who used the system suggest that the system improves upon the 'conventional' lecture in various ways. Such benefits, and some limitations, are discussed. It is suggested that student response systems such as the one described may be a step towards making 'the lecture' a more effective medium for teaching.

  5. Evidence against small dam removal as an ecological disturbance: Benthic macroinvertebrate and channel responses to dam removals in Oregon, USA

    NASA Astrophysics Data System (ADS)

    Tullos, D. D.

    2012-12-01

    A dominant concern for environmental managers is often the biological consequences of the physical disturbance generated by sediment pulses, such as those associated with dam removal or sediment flushing from existing dams. However, limited field data exists against which concerns regarding planned removals can be evaluated. This study documents an investigation of biophysical interactions related to sediment pulses from dam removals, with emphasis on a) the spatial extent and magnitude of disturbance to channel habitat and benthic macroinvertebrate community, and b) the rate and spatial patterns of channel and invertebrate community recovery over time. We analyzed field observations, collected in an upstream-downstream BACI study design, from three dam removals of varying size and channel substrate: Brownsville Dam, Calapooia River (height = 2.5 m, D50 = 59 m), Chiloquin Dam, Sprague River (height = 3.4 m, D50 = 0.15 mm), and Savage Rapids Dam, Rogue River (height = 12 m, D50 = 8 m). At each site, we investigated how elements of the physical channel related to disturbance (grain size and variability, bed stability, bed complexity) and benthic macroinvertebrate community (species richness, functional traits) changed over space and time. We projected that hypothesized changes in the physical channel (reduction in bed complexity, site-specific changes in bed mobility, site-specific grain size changes) following the sediment pulse would lead to reduction in species richness and a transition to functional traits (short lived, rapid reproduction, tolerant of mobile beds) affiliated with sediment disturbance. However, results indicate that our hypothesized channel changes were not consistently validated across the sites. Further, we found little evidence of substantial impact of the sediment pulse on the invertebrate communities, though some variability in functional traits may be attributable to dam removal at Savage Rapids. More specifically, we found that: a) Channel

  6. Ultrasonographic Investigation of Human Fetus Responses to Maternal Communicative and Non-communicative Stimuli.

    PubMed

    Ferrari, Gabriella A; Nicolini, Ylenia; Demuru, Elisa; Tosato, Cecilia; Hussain, Merhi; Scesa, Elena; Romei, Luisa; Boerci, Maria; Iappini, Emanuela; Dalla Rosa Prati, Guido; Palagi, Elisabetta; Ferrari, Pier F

    2016-01-01

    During pregnancy fetuses are responsive to the external environment, specifically to maternal stimulation. During this period, brain circuits develop to prepare neonates to respond appropriately. The detailed behavioral analysis of fetus' mouth movements in response to mothers' speech may reveal important aspects of their sensorimotor and affective skills; however, to date, no studies have investigated this response. Given that newborns at birth are capable of responding with matched behaviors to the social signals emitted by the caregiver, we hypothesize that such precocious responses could emerge in the prenatal period by exploiting infants' sensitivity to their mother's voice. By means of a two-dimensional (2D) ultrasonography, we assessed whether fetuses at 25 weeks of gestation, showed a congruent mouthmotor response to maternal acoustic stimulation. Mothers were asked to provide different stimuli, each characterized by a different acoustic output (e.g., chewing, yawning, nursery rhymes, etc.) and we recorded the behavioral responses of 29 fetuses. We found that, when mothers sang the syllable LA in a nursery rhyme, fetuses significantly increased mouth openings. Other stimuli provided by the mother did not produce other significant changes in fetus' behavior. This finding suggests that fetuses are sensitive only to specific maternal vocalizations (LA) and that fetal matched responses are rudimentary signs of early mirroring behaviors that become functional in the postnatal period. In conclusion, fetuses seem to be predisposed to respond selectively to specific maternal stimuli. We propose that such responses may play a role in the development of behavioral and emotional attunement with their mothers long before birth.

  7. Ultrasonographic Investigation of Human Fetus Responses to Maternal Communicative and Non-communicative Stimuli

    PubMed Central

    Ferrari, Gabriella A.; Nicolini, Ylenia; Demuru, Elisa; Tosato, Cecilia; Hussain, Merhi; Scesa, Elena; Romei, Luisa; Boerci, Maria; Iappini, Emanuela; Dalla Rosa Prati, Guido; Palagi, Elisabetta; Ferrari, Pier F.

    2016-01-01

    During pregnancy fetuses are responsive to the external environment, specifically to maternal stimulation. During this period, brain circuits develop to prepare neonates to respond appropriately. The detailed behavioral analysis of fetus’ mouth movements in response to mothers’ speech may reveal important aspects of their sensorimotor and affective skills; however, to date, no studies have investigated this response. Given that newborns at birth are capable of responding with matched behaviors to the social signals emitted by the caregiver, we hypothesize that such precocious responses could emerge in the prenatal period by exploiting infants’ sensitivity to their mother’s voice. By means of a two-dimensional (2D) ultrasonography, we assessed whether fetuses at 25 weeks of gestation, showed a congruent mouthmotor response to maternal acoustic stimulation. Mothers were asked to provide different stimuli, each characterized by a different acoustic output (e.g., chewing, yawning, nursery rhymes, etc.) and we recorded the behavioral responses of 29 fetuses. We found that, when mothers sang the syllable LA in a nursery rhyme, fetuses significantly increased mouth openings. Other stimuli provided by the mother did not produce other significant changes in fetus’ behavior. This finding suggests that fetuses are sensitive only to specific maternal vocalizations (LA) and that fetal matched responses are rudimentary signs of early mirroring behaviors that become functional in the postnatal period. In conclusion, fetuses seem to be predisposed to respond selectively to specific maternal stimuli. We propose that such responses may play a role in the development of behavioral and emotional attunement with their mothers long before birth. PMID:27014160

  8. Ultrasonographic Investigation of Human Fetus Responses to Maternal Communicative and Non-communicative Stimuli.

    PubMed

    Ferrari, Gabriella A; Nicolini, Ylenia; Demuru, Elisa; Tosato, Cecilia; Hussain, Merhi; Scesa, Elena; Romei, Luisa; Boerci, Maria; Iappini, Emanuela; Dalla Rosa Prati, Guido; Palagi, Elisabetta; Ferrari, Pier F

    2016-01-01

    During pregnancy fetuses are responsive to the external environment, specifically to maternal stimulation. During this period, brain circuits develop to prepare neonates to respond appropriately. The detailed behavioral analysis of fetus' mouth movements in response to mothers' speech may reveal important aspects of their sensorimotor and affective skills; however, to date, no studies have investigated this response. Given that newborns at birth are capable of responding with matched behaviors to the social signals emitted by the caregiver, we hypothesize that such precocious responses could emerge in the prenatal period by exploiting infants' sensitivity to their mother's voice. By means of a two-dimensional (2D) ultrasonography, we assessed whether fetuses at 25 weeks of gestation, showed a congruent mouthmotor response to maternal acoustic stimulation. Mothers were asked to provide different stimuli, each characterized by a different acoustic output (e.g., chewing, yawning, nursery rhymes, etc.) and we recorded the behavioral responses of 29 fetuses. We found that, when mothers sang the syllable LA in a nursery rhyme, fetuses significantly increased mouth openings. Other stimuli provided by the mother did not produce other significant changes in fetus' behavior. This finding suggests that fetuses are sensitive only to specific maternal vocalizations (LA) and that fetal matched responses are rudimentary signs of early mirroring behaviors that become functional in the postnatal period. In conclusion, fetuses seem to be predisposed to respond selectively to specific maternal stimuli. We propose that such responses may play a role in the development of behavioral and emotional attunement with their mothers long before birth. PMID:27014160

  9. Investigations into the triggered lightning response of the F106B thunderstorm research aircraft

    NASA Technical Reports Server (NTRS)

    Rudolph, Terence H.; Perala, Rodney A.; Mckenna, Paul M.; Parker, Steven L.

    1985-01-01

    An investigation has been conducted into the lightning characteristics of the NASA F106B thunderstorm research aircraft. The investigation includes analysis of measured data from the aircraft in the time and frequency domains. Linear and nonlinear computer modelling has also been performed. In addition, new computer tools have been developed, including a new enhanced nonlinear air breakdown model, and a subgrid model useful for analyzing fine details of the aircraft's geometry. Comparison of measured and calculated electromagnetic responses of the aircraft to a triggered lightning environment are presented.

  10. Investigation on spectral response of micro-cavity structure by symmetrical tapered fiber tips

    NASA Astrophysics Data System (ADS)

    Liu, Yan; Li, Yang; Yan, Xiaojun; Li, Weidong

    2016-06-01

    We proposed and experimentally demonstrated a micro-cavity structure made of symmetrical tapered fiber tips. The waist of a conventional fiber taper fabricated from heating and stretching technique is symmetrically cleaved, and the aligned fiber tips with air gap constitute a Fabry-Perot micro-cavity due to the reflection at the tip facet. The spectral responses of such micro-cavity structure have been investigated both in beam propagation models and experiments. The multibeam interference in the micro-cavity and the impact of the waist diameter and cavity length on the spectral response has been successfully demonstrated. And a micro-cavity structure with 45 μm waist diameter was experimentally achieved, the measured spectra agree well with the simulation ones, indicating that the spectral response of the micro-cavity structure is contributed by both the multibeam interference and the Fabry-Perot micro-cavity.

  11. Investigation of the Gracilaria gracilis (Gracilariales, Rhodophyta) proteome response to nitrogen limitation.

    PubMed

    Naidoo, Rene K; Rafudeen, Muhammad S; Coyne, Vernon E

    2016-06-01

    Inorganic nitrogen has been identified as the major growth-limiting nutritional factor affecting Gracilaria gracilis populations in South Africa. Although the physiological mechanisms implemented by G. gracilis for adaption to low nitrogen environments have been investigated, little is known about the molecular mechanisms of these adaptions. This study provides the first investigation of G. gracilis proteome changes in response to nitrogen limitation and subsequent recovery. A differential proteomics approach employing two-dimensional gel electrophoresis and liquid chromatography-tandem mass spectrometry was used to investigate G. gracilis proteome changes in response to nitrogen limitation and recovery. The putative identity of 22 proteins that changed significantly (P < 0.05) in abundance in response to nitrogen limitation and recovery was determined. The identified proteins function in a range of biological processes including glycolysis, photosynthesis, ATP synthesis, galactose metabolism, protein-refolding and biosynthesis, nitrogen metabolism and cytoskeleton remodeling. The identity of fructose 1,6 biphosphate (FBP) aldolase was confirmed by western blot analysis and the decreased abundance of FBP aldolase observed with two-dimensional gel electrophoresis was validated by enzyme assays and western blots. The identification of key proteins and pathways involved in the G. gracilis nitrogen stress response provide a better understanding of G. gracilis proteome responses to varying degrees of nitrogen limitation and is the first step in the identification of biomarkers for monitoring the nitrogen status of cultivated G. gracilis populations.

  12. Investigation of pitch motion portion in vertical response at sides of a Tension-Leg Platform

    NASA Astrophysics Data System (ADS)

    Tabeshpour, Mohammad Reza; Malayjerdi, Ebrahim

    2016-06-01

    Tendons vertically moor Tension-Leg Platforms (TLPs), thus, a deep understanding of physical tendon stresses requires the determination of the total axial deformation of the tendons, which is a combination of the heave, pitch, and surging responses. The vertical motion of the lateral sides of the TLP is coupled with surge and constitutes a portion of the pitch motion. Tendons are connected to the sides of the TLP; hence, the total displacement of the lateral sides is related to the total deformation of the tendons and the total axial stress. Therefore, investigating the total vertical response at the sides of the TLP is essential. The coupling between various degrees of freedom is not considered in the Response Amplitude Operator (RAO). Therefore, in frequency domain analysis, the estimated vertical RAO is incomplete. Also, in the time domain, only the heave motion at the center of TLP is typically studied; this problem needs to be addressed. In this paper, we investigate the portion of the pitch motion in the vertical response at the sides of the TLP in both the frequency and time domains. Numerical results demonstrate a significant effect of the pitch motion in the vertical motion of the edges of the TLP in some period ranges.

  13. Ecological Insights from Pelagic Habitats Acquired Using Active Acoustic Techniques

    NASA Astrophysics Data System (ADS)

    Benoit-Bird, Kelly J.; Lawson, Gareth L.

    2016-01-01

    Marine pelagic ecosystems present fascinating opportunities for ecological investigation but pose important methodological challenges for sampling. Active acoustic techniques involve producing sound and receiving signals from organisms and other water column sources, offering the benefit of high spatial and temporal resolution and, via integration into different platforms, the ability to make measurements spanning a range of spatial and temporal scales. As a consequence, a variety of questions concerning the ecology of pelagic systems lend themselves to active acoustics, ranging from organism-level investigations and physiological responses to the environment to ecosystem-level studies and climate. As technologies and data analysis methods have matured, the use of acoustics in ecological studies has grown rapidly. We explore the continued role of active acoustics in addressing questions concerning life in the ocean, highlight creative applications to key ecological themes ranging from physiology and behavior to biogeography and climate, and discuss emerging avenues where acoustics can help determine how pelagic ecosystems function.

  14. Ecological Insights from Pelagic Habitats Acquired Using Active Acoustic Techniques.

    PubMed

    Benoit-Bird, Kelly J; Lawson, Gareth L

    2016-01-01

    Marine pelagic ecosystems present fascinating opportunities for ecological investigation but pose important methodological challenges for sampling. Active acoustic techniques involve producing sound and receiving signals from organisms and other water column sources, offering the benefit of high spatial and temporal resolution and, via integration into different platforms, the ability to make measurements spanning a range of spatial and temporal scales. As a consequence, a variety of questions concerning the ecology of pelagic systems lend themselves to active acoustics, ranging from organism-level investigations and physiological responses to the environment to ecosystem-level studies and climate. As technologies and data analysis methods have matured, the use of acoustics in ecological studies has grown rapidly. We explore the continued role of active acoustics in addressing questions concerning life in the ocean, highlight creative applications to key ecological themes ranging from physiology and behavior to biogeography and climate, and discuss emerging avenues where acoustics can help determine how pelagic ecosystems function.

  15. Ecological Insights from Pelagic Habitats Acquired Using Active Acoustic Techniques.

    PubMed

    Benoit-Bird, Kelly J; Lawson, Gareth L

    2016-01-01

    Marine pelagic ecosystems present fascinating opportunities for ecological investigation but pose important methodological challenges for sampling. Active acoustic techniques involve producing sound and receiving signals from organisms and other water column sources, offering the benefit of high spatial and temporal resolution and, via integration into different platforms, the ability to make measurements spanning a range of spatial and temporal scales. As a consequence, a variety of questions concerning the ecology of pelagic systems lend themselves to active acoustics, ranging from organism-level investigations and physiological responses to the environment to ecosystem-level studies and climate. As technologies and data analysis methods have matured, the use of acoustics in ecological studies has grown rapidly. We explore the continued role of active acoustics in addressing questions concerning life in the ocean, highlight creative applications to key ecological themes ranging from physiology and behavior to biogeography and climate, and discuss emerging avenues where acoustics can help determine how pelagic ecosystems function. PMID:26515810

  16. 42 CFR 480.137 - Disclosure to Federal and State enforcement agencies responsible for the investigation or...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... agencies responsible for the investigation or identification of fraud or abuse of the Medicare or Medicaid... State enforcement agencies responsible for the investigation or identification of fraud or abuse of the... confidential information relevant to an investigation of fraud or abuse of the Medicare or medicaid...

  17. 42 CFR 480.137 - Disclosure to Federal and State enforcement agencies responsible for the investigation or...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... agencies responsible for the investigation or identification of fraud or abuse of the Medicare or Medicaid... State enforcement agencies responsible for the investigation or identification of fraud or abuse of the... confidential information relevant to an investigation of fraud or abuse of the Medicare or medicaid...

  18. Hydrologic, ecologic, and geomorphic responses of Brewery Creek to construction of a residential subdivision, Dane County, Wisconsin, 1999-2002

    USGS Publications Warehouse

    Selbig, William R.; Jopke, Peter L.; Marhshall, David W.; Sorge, Michael J.

    2004-01-01

    Other physical, biological, and ecological surveys including macroinvertebrates, fish, habitat, and geomorphology were done on segments of Brewery Creek affected by the study area. Macroinvertebrate sampling results (Hilsenhoff Biotic Index value, or HBI), on Brewery Creek ranged from 'very good' to 'good' water-quality with no appreciable differences during any phase of construction activity. Results for fish-community composition, however, were within the 'poor' range (Index of Biotic Integrity value, or IBI) during each year of testing. A general absence of intolerant species, with the exception of brown trout, reflects the low IBI values. Habitat values did not change significantly from preconstruction to postconstruction phases. Although installation of a double-celled culvert in Brewery Creek most likely altered the width-to-depth ratio in that reach, the overall habitat rating remained 'fair'. Fluvial geomorphology classifications including channel cross sections, bed- and bank-erosion surveys, and pebble counts did not indicate that stream geomorphic characteristics were altered by home-construction activity in the study area. Increases in fine-grained sediment at various cross sections were attributed to instream erosion processes, such as bank slumping, rather than increases in sediment delivery from the nearby construction site.

  19. Sustainability Evaluation of the Grain for Green Project: From Local People's Responses to Ecological Effectiveness in Wolong Nature Reserve

    NASA Astrophysics Data System (ADS)

    Xu, Jian-Ying; Chen, Li-Ding; Lu, Yi-He; Fu, Bo-Jie

    2007-07-01

    This article examines the sustainability of the Grain for Green Project in the Wolong Nature Reserve. Pertinent data were collected through a questionnaire survey and a spatial analysis of reforested lands. The study results identified four critical issues that may influence the sustainability of the project in the study area. The first issue is concerned with the project’s impacts on local sustenance. Because local grain consumption depends greatly on compensation awarded by the project, the potential for sustainability of the project is compromised. The second issue is that the project causes negative effects on local incomes in the Wolong Nature Reserve, which may undermine local economic prospects. The third issue is that the project failed to deliver suitable habitat for the giant panda, although two of the suitability requirements that deal with landform features were met. Lastly, the project neglects great differences among geographical areas in the country, providing the same compensation and length of compensation period to all participants. Appropriate compensation mechanisms should be established and adapted to local economic, environmental, and social conditions. In managing nature reserves and moving toward sustainability, ensuring all aspects of local socioeconomic and ecological/environmental issues are properly addressed is a real challenge. Based on our study, some recommendations for improving sustainability of the project are given.

  20. Sustainability evaluation of the Grain for Green Project: from local people's responses to ecological effectiveness in Wolong Nature Reserve.

    PubMed

    Xu, Jian-Ying; Chen, Li-Ding; Lu, Yi-He; Fu, Bo-Jie

    2007-07-01

    This article examines the sustainability of the Grain for Green Project in the Wolong Nature Reserve. Pertinent data were collected through a questionnaire survey and a spatial analysis of reforested lands. The study results identified four critical issues that may influence the sustainability of the project in the study area. The first issue is concerned with the project's impacts on local sustenance. Because local grain consumption depends greatly on compensation awarded by the project, the potential for sustainability of the project is compromised. The second issue is that the project causes negative effects on local incomes in the Wolong Nature Reserve, which may undermine local economic prospects. The third issue is that the project failed to deliver suitable habitat for the giant panda, although two of the suitability requirements that deal with landform features were met. Lastly, the project neglects great differences among geographical areas in the country, providing the same compensation and length of compensation period to all participants. Appropriate compensation mechanisms should be established and adapted to local economic, environmental, and social conditions. In managing nature reserves and moving toward sustainability, ensuring all aspects of local socioeconomic and ecological/environmental issues are properly addressed is a real challenge. Based on our study, some recommendations for improving sustainability of the project are given.

  1. Ecological ethics in captivity: balancing values and responsibilities in zoo and aquarium research under rapid global change.

    PubMed

    Minteer, Ben A; Collins, James P

    2013-01-01

    Ethical obligations to animals in conservation research and management are manifold and often conflicting. Animal welfare concerns often clash with the ethical imperative to understand and conserve a population or ecosystem through research and management intervention. The accelerating pace and impact of global environmental change, especially climate change, complicates our understanding of these obligations. One example is the blurring of the distinction between ex situ (zoo- and aquarium-based) conservation and in situ (field-based) approaches as zoos and aquariums become more active in field conservation work and as researchers and managers consider more intensive interventions in wild populations and ecosystems to meet key conservation goals. These shifts, in turn, have consequences for our traditional understanding of the ethics of wildlife research and management, including our relative weighting of animal welfare and conservation commitments across rapidly evolving ex situ and in situ contexts. Although this changing landscape in many ways supports the increased use of captive wildlife in conservation-relevant research, it raises significant ethical concerns about human intervention in populations and ecosystems, including the proper role of zoos and aquariums as centers for animal research and conservation in the coming decades. Working through these concerns requires a pragmatic approach to ethical analysis, one that is able to make trade-offs among the many goods at stake (e.g., animal welfare, species viability, and ecological integrity) as we strive to protect species from further decline and extinction in this century.

  2. Ecological ethics in captivity: balancing values and responsibilities in zoo and aquarium research under rapid global change.

    PubMed

    Minteer, Ben A; Collins, James P

    2013-01-01

    Ethical obligations to animals in conservation research and management are manifold and often conflicting. Animal welfare concerns often clash with the ethical imperative to understand and conserve a population or ecosystem through research and management intervention. The accelerating pace and impact of global environmental change, especially climate change, complicates our understanding of these obligations. One example is the blurring of the distinction between ex situ (zoo- and aquarium-based) conservation and in situ (field-based) approaches as zoos and aquariums become more active in field conservation work and as researchers and managers consider more intensive interventions in wild populations and ecosystems to meet key conservation goals. These shifts, in turn, have consequences for our traditional understanding of the ethics of wildlife research and management, including our relative weighting of animal welfare and conservation commitments across rapidly evolving ex situ and in situ contexts. Although this changing landscape in many ways supports the increased use of captive wildlife in conservation-relevant research, it raises significant ethical concerns about human intervention in populations and ecosystems, including the proper role of zoos and aquariums as centers for animal research and conservation in the coming decades. Working through these concerns requires a pragmatic approach to ethical analysis, one that is able to make trade-offs among the many goods at stake (e.g., animal welfare, species viability, and ecological integrity) as we strive to protect species from further decline and extinction in this century. PMID:23904531

  3. Dose-response investigation into glucose facilitation of memory performance and mood in healthy young adults.

    PubMed

    Sünram-Lea, Sandra I; Owen, Lauren; Finnegan, Yvonne; Hu, Henglong

    2011-08-01

    It has been suggested that the memory enhancing effect of glucose follows an inverted U-shaped curve, with 25 g resulting in optimal facilitation in healthy young adults. The aim of this study was to further investigate the dose dependency of the glucose facilitation effect in this population across different memory domains and to assess moderation by interindividual differences in glucose regulation and weight. Following a double-blind, repeated measures design, 30 participants were administered drinks containing five different doses of glucose (0 g, 15 g, 25 g, 50 g, and 60 g) and were tested across a range of memory tasks. Glycaemic response and changes in mood state were assessed following drink administration. Analysis of the data showed that glucose administration did not affect mood, but significant glucose facilitation of several memory tasks was observed. However, dose-response curves differed depending on the memory task with only performance on the long-term memory tasks adhering largely to the previously observed inverted U-shaped dose-response curve. Moderation of the response profiles by interindividual differences in glucose regulation and weight was observed. The current data suggest that dose-response function and optimal dose might depend on cognitive domain and are moderated by interindividual differences in glucose regulation and weight.

  4. Art expertise modulates the emotional response to modern art, especially abstract: an ERP investigation.

    PubMed

    Else, Jane E; Ellis, Jason; Orme, Elizabeth

    2015-01-01

    Art is one of life's great joys, whether it is beautiful, ugly, sublime or shocking. Aesthetic responses to visual art involve sensory, cognitive and visceral processes. Neuroimaging studies have yielded a wealth of information regarding aesthetic appreciation and beauty using visual art as stimuli, but few have considered the effect of expertise on visual and visceral responses. To study the time course of visual, cognitive and emotional processes in response to visual art we investigated the event-related potentials (ERPs) elicited whilst viewing and rating the visceral affect of three categories of visual art. Two groups, artists and non-artists viewed representational, abstract and indeterminate 20th century art. Early components, particularly the N1, related to attention and effort, and the P2, linked to higher order visual processing, was enhanced for artists when compared to non-artists. This effect was present for all types of art, but further enhanced for abstract art (AA), which was rated as having lowest visceral affect by the non-artists. The later, slow wave processes (500-1000 ms), associated with arousal and sustained attention, also show clear differences between the two groups in response to both type of art and visceral affect. AA increased arousal and sustained attention in artists, whilst it decreased in non-artists. These results suggest that aesthetic response to visual art is affected by both expertise and semantic content.

  5. Art expertise modulates the emotional response to modern art, especially abstract: an ERP investigation

    PubMed Central

    Else, Jane E.; Ellis, Jason; Orme, Elizabeth

    2015-01-01

    Art is one of life’s great joys, whether it is beautiful, ugly, sublime or shocking. Aesthetic responses to visual art involve sensory, cognitive and visceral processes. Neuroimaging studies have yielded a wealth of information regarding aesthetic appreciation and beauty using visual art as stimuli, but few have considered the effect of expertise on visual and visceral responses. To study the time course of visual, cognitive and emotional processes in response to visual art we investigated the event-related potentials (ERPs) elicited whilst viewing and rating the visceral affect of three categories of visual art. Two groups, artists and non-artists viewed representational, abstract and indeterminate 20th century art. Early components, particularly the N1, related to attention and effort, and the P2, linked to higher order visual processing, was enhanced for artists when compared to non-artists. This effect was present for all types of art, but further enhanced for abstract art (AA), which was rated as having lowest visceral affect by the non-artists. The later, slow wave processes (500–1000 ms), associated with arousal and sustained attention, also show clear differences between the two groups in response to both type of art and visceral affect. AA increased arousal and sustained attention in artists, whilst it decreased in non-artists. These results suggest that aesthetic response to visual art is affected by both expertise and semantic content. PMID:27242497

  6. Investigation of Response Amplitude Operators for Floating Offshore Wind Turbines: Preprint

    SciTech Connect

    Ramachandran, G. K. V.; Robertson, A.; Jonkman, J. M.; Masciola, M. D.

    2013-07-01

    This paper examines the consistency between response amplitude operators (RAOs) computed from WAMIT, a linear frequency-domain tool, to RAOs derived from time-domain computations based on white-noise wave excitation using FAST, a nonlinear aero-hydro-servo-elastic tool. The RAO comparison is first made for a rigid floating wind turbine without wind excitation. The investigation is further extended to examine how these RAOs change for a flexible and operational wind turbine. The RAOs are computed for below-rated, rated, and above-rated wind conditions. The method is applied to a floating wind system composed of the OC3-Hywind spar buoy and NREL 5-MW wind turbine. The responses are compared between FAST and WAMIT to verify the FAST model and to understand the influence of structural flexibility, aerodynamic damping, control actions, and waves on the system responses. The results show that based on the RAO computation procedure implemented, the WAMIT- and FAST-computed RAOs are similar (as expected) for a rigid turbine subjected to waves only. However, WAMIT is unable to model the excitation from a flexible turbine. Further, the presence of aerodynamic damping decreased the platform surge and pitch responses, as computed by both WAMIT and FAST when wind was included. Additionally, the influence of gyroscopic excitation increased the yaw response, which was captured by both WAMIT and FAST.

  7. Responses of soil microbial biomass and bacterial community structure to closed-off management (an ecological natural restoration measures): A case study of Dongting Lake wetland, middle China.

    PubMed

    Dai, Juan; Wu, Haipeng; Zhang, Chang; Zeng, Guangming; Liang, Jie; Guo, Shenglian; Li, Xiaodong; Huang, Lu; Lu, Lunhui; Yuan, Yujie

    2016-09-01

    Soil microbial biomass (SMB) and bacterial community structure, which are critical to global ecosystem and fundamental ecological processes, are sensitive to anthropogenic activities and environmental conditions. In this study, we examined the possible effects of closed-off management (an ecological natural restoration measures, ban on anthropogenic activity, widely employed for many important wetlands) on SMB, soil bacterial community structure and functional marker genes of nitrogen cycling in Dongting Lake wetland. Soil samples were collected from management area (MA) and contrast area (CA: human activities, such as hunting, fishing and draining, are permitted) in November 2013 and April 2014. Soil properties, microbial biomass carbon (MBC), and bacterial community structure were investigated. Comparison of the values of MA and CA showed that SMB and bacterial community diversity of the MA had a significant increase after 7 years closed-off management. The mean value of Shannon-Weiner diversity index of MA and CA respectively were 2.85 and 2.07. The gene copy numbers of 16S rRNA and nosZ of MA were significant higher than those of CA. the gene copy numbers of ammonia-oxidizing archaea (AOA) and nirK of MA were significant lower than those of CA. However, there was no significant change in the gene copy numbers of ammonia-oxidizing bacteria (AOB) and nirS.

  8. Responses of soil microbial biomass and bacterial community structure to closed-off management (an ecological natural restoration measures): A case study of Dongting Lake wetland, middle China.

    PubMed

    Dai, Juan; Wu, Haipeng; Zhang, Chang; Zeng, Guangming; Liang, Jie; Guo, Shenglian; Li, Xiaodong; Huang, Lu; Lu, Lunhui; Yuan, Yujie

    2016-09-01

    Soil microbial biomass (SMB) and bacterial community structure, which are critical to global ecosystem and fundamental ecological processes, are sensitive to anthropogenic activities and environmental conditions. In this study, we examined the possible effects of closed-off management (an ecological natural restoration measures, ban on anthropogenic activity, widely employed for many important wetlands) on SMB, soil bacterial community structure and functional marker genes of nitrogen cycling in Dongting Lake wetland. Soil samples were collected from management area (MA) and contrast area (CA: human activities, such as hunting, fishing and draining, are permitted) in November 2013 and April 2014. Soil properties, microbial biomass carbon (MBC), and bacterial community structure were investigated. Comparison of the values of MA and CA showed that SMB and bacterial community diversity of the MA had a significant increase after 7 years closed-off management. The mean value of Shannon-Weiner diversity index of MA and CA respectively were 2.85 and 2.07. The gene copy numbers of 16S rRNA and nosZ of MA were significant higher than those of CA. the gene copy numbers of ammonia-oxidizing archaea (AOA) and nirK of MA were significant lower than those of CA. However, there was no significant change in the gene copy numbers of ammonia-oxidizing bacteria (AOB) and nirS. PMID:27036597

  9. Cognitive ecology.

    PubMed

    Hutchins, Edwin

    2010-10-01

    Cognitive ecology is the study of cognitive phenomena in context. In particular, it points to the web of mutual dependence among the elements of a cognitive ecosystem. At least three fields were taking a deeply ecological approach to cognition 30 years ago: Gibson's ecological psychology, Bateson's ecology of mind, and Soviet cultural-historical activity theory. The ideas developed in those projects have now found a place in modern views of embodied, situated, distributed cognition. As cognitive theory continues to shift from units of analysis defined by inherent properties of the elements to units defined in terms of dynamic patterns of correlation across elements, the study of cognitive ecosystems will become an increasingly important part of cognitive science.

  10. Investigating the response of East Asian ozone to Chinese emission changes using a linear approach

    NASA Astrophysics Data System (ADS)

    Yamaji, Kazuyo; Uno, Itsushi; Irie, Hitoshi

    2012-08-01

    To illuminate the issue of trans-boundary O3 pollution and regional O3 reduction policies in East Asia, we have investigated the East Asian ozone (O3) response to perturbations caused by Chinese anthropogenic emissions using the Community Multiscale Air Quality (CMAQ) model, a regional chemical transport model. The O3 responses have been examined for the range between -100 and +100% changes from the Chinese emissions level in 2004 in 10% intervals. We have found that springtime and summertime O3 responses both at the source and at the downwind areas can be regarded as linear over the range between -30 and +100% changes from the current emissions level. We therefore suggest that the perturbation between -30 and +100% is sufficiently small to avoid nonlinear chemical influence on O3 formation in a model experiment to investigate East Asian scale O3 source-receptor relationships. On the other hand, the O3 response is strongly nonlinear in April at Hong Kong, where the current NMVOCs/NOx ratio is low and the O3 production regime is easily moved to the NMVOCs sensitive region. The O3 responses to the NOx emission changes have been investigated using surface O3 concentrations at remote Japanese sites and tropospheric NO2 vertical column density (NO2 VCD) over central east China both with observations and with model simulations in springtime during 2003-2009. Analysis of satellite data shows that the observed range of NO2 VCD over central east China in 2003-2009 is the range between -25 and +34% from the 2004 level, which corresponds approximately to an emission variation between -21 and +29%. The O3 concentration in the downwind region during 2003-2009 responds linearly to a change of the NO2 VCD over central east China both in the model and in the observation. The corresponding O3 responses derived from surface observations at remote Japanese sites show linear features consistent with this expectation. The doubling of emissions, i.e., approximately 1.9-fold increase in

  11. Investigation of urban science teachers' pedagogical engagements: Are urban science teachers culturally responsive?

    NASA Astrophysics Data System (ADS)

    Udokwu, Chukwudi John

    This study utilized mixed methodology of quantitative and qualitative research approach to explore the current pedagogical engagements of twenty middle school urban science teachers in the Midwest region of the United States. It qualitatively examined twelve of these teachers' knowledge of culturally responsive pedagogy. The study investigated the following questions: What are the current pedagogical practices of urban middle school science teachers? To what extent are middle school science teachers' pedagogical practices in urban schools culturally responsive? What are urban students' perspectives of their teachers' current pedagogical engagements? The design of the study was qualitative and quantitative methods in order to investigate these teachers' pedagogical practices. Data collections were drawn from multiple sources such as lesson plans, students' sample works, district curriculum, surveys, observational and interview notes. Analysis of collected data was a mixed methodology that involved qualitative and quantitative methods using descriptive, interpretative, pattern codes, and statistical procedures respectively. Purposeful sampling was selected for this study. Thus, demographically there were twenty participants who quantitatively took part in this study. Among them were seven (35%) males and thirteen (65%) females, three (15%) African Americans and seventeen (85%) Caucasians. In determining to what extent urban science teachers' pedagogical practices were culturally responsive, eight questions were analyzed based on four cluster themes: (a) teachers' social disposition, (b) culturally responsive curriculum, (c) classroom interactions, and (d) power pedagogy. Study result revealed that only five (25%) of the participants were engaged in culturally responsive pedagogy while fifteen (75%) were engaged in what Haberman (1991) called the pedagogy of poverty. The goal was to investigate urban science teachers' pedagogical engagements and to examine urban

  12. Functional Molecular Ecological Networks

    PubMed Central

    Zhou, Jizhong; Deng, Ye; Luo, Feng; He, Zhili; Tu, Qichao; Zhi, Xiaoyang

    2010-01-01

    Biodiversity and its responses to environmental changes are central issues in ecology and for society. Almost all microbial biodiversity research focuses on “species” richness and abundance but not on their interactions. Although a network approach is powerful in describing ecological interactions among species, defining the network structure in a microbial community is a great challenge. Also, although the stimulating effects of elevated CO2 (eCO2) on plant growth and primary productivity are well established, its influences on belowground microbial communities, especially microbial interactions, are poorly understood. Here, a random matrix theory (RMT)-based conceptual framework for identifying functional molecular ecological networks was developed with the high-throughput functional gene array hybridization data of soil microbial communities in a long-term grassland FACE (free air, CO2 enrichment) experiment. Our results indicate that RMT is powerful in identifying functional molecular ecological networks in microbial communities. Both functional molecular ecological networks under eCO2 and ambient CO2 (aCO2) possessed the general characteristics of complex systems such as scale free, small world, modular, and hierarchical. However, the topological structures of the functional molecular ecological networks are distinctly different between eCO2 and aCO2, at the levels of the entire communities, individual functional gene categories/groups, and functional genes/sequences, suggesting that eCO2 dramatically altered the network interactions among different microbial functional genes/populations. Such a shift in network structure is also significantly correlated with soil geochemical variables. In short, elucidating network interactions in microbial communities and their responses to environmental changes is fundamentally important for research in microbial ecology, systems microbiology, and global change. PMID:20941329

  13. Biophysical Investigation of Tissue Dynamics and Evidence for a Wounding Response

    NASA Astrophysics Data System (ADS)

    Edwards, Glenn; Tokutake, Yoichiro; Peralta, Xomalin; Mao, Albert; Hutson, M. Shane; Venakides, Stephanos; Kiehart, Dan

    2003-11-01

    We have been investigating the forces responsible for tissue dynamics in the fruit fly Drosophila, focusing on dorsal closure where two sheets of lateral epidermis close over a sheet of amnioserosa. Dorsal closure is a model system for various aspects of cell movement in vertebrate development and wound healing. We have refined a UV-laser microbeam to perturb the system; (visible) laser confocal microscopy has been used to visualize the response; and a theoretical model has been proposed to account for dorsal closure in terms of four force producing processes that are coordinated in space and synchronized in time (1). Here we report on the response to specific wounding patterns that interrogate zipping, one of these processes. We account for the responses, and find evidence that for some patterns the force produced by the amnioserosa increases as a consequence of wounding allowing dorsal closure to complete on schedule. This research has been supported by the DoD MFEL Program and by the NIH. 1. Science 300, 145-149 (2003).

  14. Investigation of hydroelastic ship responses of an ULOC in head seas

    NASA Astrophysics Data System (ADS)

    Wang, Xue-liang; Temarel, Pandeli; Hu, Jia-jun; Gu, Xue-kang

    2016-10-01

    Investigation of hydroelastic ship responses has been brought to the attention of the scientific and engineering world for several decades. There are two kinds of high-frequency vibrations in general ship responses to a large ocean-going ship in its shipping line, so-called springing and whipping, which are important for the determination of design wave load and fatigue damage as well. Because of the huge scale of an ultra large ore carrier (ULOC), it will suffer seldom slamming events in the ocean. The resonance vibration with high frequency is springing, which is caused by continuous wave excitation. In this paper, the wave-induced vibrations of the ULOC are addressed by experimental and numerical methods according to 2D and 3D hydroelasticity theories and an elastic model under full-load and ballast conditions. The influence of loading conditions on high-frequency vibration is studied both by numerical and experimental results. Wave-induced vibrations are higher under ballast condition including the wave frequency part, the multiple frequencies part, the 2-node and the 3-node vertical bending parts of the hydroelastic responses. The predicted results from the 2D method have less accuracy than the 3D method especially under ballast condition because of the slender-body assumption in the former method. The applicability of the 2D method and the further development of nonlinear effects to 3D method in the prediction of hydroelastic responses of the ULOC are discussed.

  15. Computational investigation of the mechanical and tribological responses of amorphous carbon nanoparticles

    NASA Astrophysics Data System (ADS)

    Bucholz, Eric W.; Sinnott, Susan B.

    2013-02-01

    Nanoparticles are a class of materials that have seen increasing use as friction and wear reducers in tribological applications. Amorphous carbon (a-C) films have been the subject of significant scientific and industrial interest for use as solid-state lubricants. Here, we present classical molecular dynamics simulations to investigate the mechanical and tribological responses of a-C nanoparticles that are subjected to external forces between hydrogen-terminated diamond surfaces. Over the range of a-C nanoparticle diameters (2-5 nm) and hydrogenation (0%-50%) considered, the simulations predict a consistent mechanical response where each nanoparticle is highly elastic. The simulations predict that the transition from elastic to plastic response is directly related to an increase in the percentage of carbon-carbon crosslinking within the individual nanoparticles. Contrarily, the simulations also predict that the tribological response is noticeably impacted by changes in diameter and hydrogenation. This is because during friction, hydrogen passivates the unsaturated carbon atoms near the nanoparticle's surface, which prevents interfacial bond formation and allows the nanoparticle to roll within the interface. From these findings, it is demonstrated that a-C nanoparticles are able to provide good tribological performance only when sufficient chemical passivation of the nanoparticles is maintained.

  16. Investigation on the forced response of a radial turbine under aerodynamic excitations

    NASA Astrophysics Data System (ADS)

    Ma, Chaochen; Huang, Zhi; Qi, Mingxu

    2016-04-01

    Rotor blades in a radial turbine with nozzle guide vanes typically experience harmonic aerodynamic excitations due to the rotor stator interaction. Dynamic stresses induced by the harmonic excitations can result in high cycle fatigue (HCF) of the blades. A reliable prediction method for forced response issue is essential to avoid the HCF problem. In this work, the forced response mechanisms were investigated based on a fluid structure interaction (FSI) method. Aerodynamic excitations were obtained by three-dimensional unsteady computational fluid dynamics (CFD) simulation with phase shifted periodic boundary conditions. The first two harmonic pressures were determined as the primary components of the excitation and applied to finite element (FE) model to conduct the computational structural dynamics (CSD) simulation. The computed results from the harmonic forced response analysis show good agreement with the predictions of Singh's advanced frequency evaluation (SAFE) diagram. Moreover, the mode superposition method used in FE simulation offers an efficient way to provide quantitative assessments of mode response levels and resonant strength.

  17. Investigating the functionality of an OCT4-short response element in human induced pluripotent stem cells.

    PubMed

    Vega-Crespo, Agustin; Truong, Brian; Hermann, Kip J; Awe, Jason P; Chang, Katherine M; Lee, Patrick C; Schoenberg, Benjamen E; Wu, Lily; Byrne, James A; Lipshutz, Gerald S

    2016-01-01

    Pluripotent stem cells offer great therapeutic promise for personalized treatment platforms for numerous injuries, disorders, and diseases. Octamer-binding transcription factor 4 (OCT4) is a key regulatory gene maintaining pluripotency and self-renewal of mammalian cells. With site-specific integration for gene correction in cellular therapeutics, use of the OCT4 promoter may have advantages when expressing a suicide gene if pluripotency remains. However, the human OCT4 promoter region is 4 kb in size, limiting the capacity of therapeutic genes and other regulatory components for viral vectors, and decreasing the efficiency of homologous recombination. The purpose of this investigation was to characterize the functionality of a novel 967bp OCT4-short response element during pluripotency and to examine the OCT4 titer-dependent response during differentiation to human derivatives not expressing OCT4. Our findings demonstrate that the OCT4-short response element is active in pluripotency and this activity is in high correlation with transgene expression in vitro, and the OCT4-short response element is inactivated when pluripotent cells differentiate. These studies demonstrate that this shortened OCT4 regulatory element is functional and may be useful as part of an optimized safety component in a site-specific gene transferring system that could be used as an efficient and clinically applicable safety platform for gene transfer in cellular therapeutics. PMID:27500178

  18. Investigating the functionality of an OCT4-short response element in human induced pluripotent stem cells

    PubMed Central

    Vega-Crespo, Agustin; Truong, Brian; Hermann, Kip J; Awe, Jason P; Chang, Katherine M; Lee, Patrick C; Schoenberg, Benjamen E; Wu, Lily; Byrne, James A; Lipshutz, Gerald S

    2016-01-01

    Pluripotent stem cells offer great therapeutic promise for personalized treatment platforms for numerous injuries, disorders, and diseases. Octamer-binding transcription factor 4 (OCT4) is a key regulatory gene maintaining pluripotency and self-renewal of mammalian cells. With site-specific integration for gene correction in cellular therapeutics, use of the OCT4 promoter may have advantages when expressing a suicide gene if pluripotency remains. However, the human OCT4 promoter region is 4 kb in size, limiting the capacity of therapeutic genes and other regulatory components for viral vectors, and decreasing the efficiency of homologous recombination. The purpose of this investigation was to characterize the functionality of a novel 967bp OCT4-short response element during pluripotency and to examine the OCT4 titer-dependent response during differentiation to human derivatives not expressing OCT4. Our findings demonstrate that the OCT4-short response element is active in pluripotency and this activity is in high correlation with transgene expression in vitro, and the OCT4-short response element is inactivated when pluripotent cells differentiate. These studies demonstrate that this shortened OCT4 regulatory element is functional and may be useful as part of an optimized safety component in a site-specific gene transferring system that could be used as an efficient and clinically applicable safety platform for gene transfer in cellular therapeutics. PMID:27500178

  19. Investigation of Responsiveness to Thyrotropin-Releasing Hormone in Growth Hormone-Producing Pituitary Adenomas

    PubMed Central

    Chin, Sang Ouk; Hwang, You-Cheol; Jeong, In-Kyung; Oh, Seungjoon

    2013-01-01

    Objective. The aim of this study was to investigate how the paradoxical response of GH secretion to TRH changes according to tumor volumes. Methods. Patients with newly diagnosed acromegaly were classified as either TRH responders or nonresponders according to the results of a TRH stimulation test (TST), and their clinical characteristics were compared according to responsiveness to TRH and tumor volumes. Results. A total of 41 acromegalic patients who underwent the TST were included in this study. Between TRH responders and nonresponders, basal GH, IGF-I levels, peak GH levels, and tumor volume were not significantly different, but the between-group difference of GH levels remained near significant over the entire TST time. ΔGHmax-min during the TST were significantly different according to the responsiveness to TRH. Peak GH levels and ΔGHmax-min during the TST showed significantly positive correlations with tumor volume with higher levels in macroadenomas than in microadenomas. GH levels over the entire TST time also remained significantly higher in macroadenomas than in microadenomas. Conclusion. Our data demonstrated that the paradoxical response of GH secretion to TRH in GH-producing pituitary adenomas was not inversely correlated with tumor volumes. PMID:24348552

  20. An Investigation of the Dynamic Response of Spur Gear Teeth with Moving Loads

    NASA Technical Reports Server (NTRS)

    Passerello, C. E.; Shuey, L. W.

    1987-01-01

    Two concepts relating to gear dynamics were studied. The first phase of the analysis involved the study of the effect of the speed of a moving load on the dynamic deflections of a gear tooth. A single spur gear tooth modelled using finite elements was subjected to moving loads with variable velocities. The tooth tip deflection time histories were plotted, from which it was seen that the tooth tip deflection consisted of a quasistatic response with an oscillatory response superimposed on it whose amplitude was dependent on the type of load engagement. Including the rim in the analysis added flexibility to the model but did not change the general behavior of the system. The second part of the analysis involved an investigation to determine the effect on the dynamic response of the inertia of the gear tooth. A simplified analysis using meshing cantilever beams was used. In one case, the beams were assumed massless. In the other, the mass (inertia) of the beams was included. From this analysis it was found that the inertia of the tooth did not affect the dynamic response of meshing cantilever beams.

  1. Role of law enforcement response and microbial forensics in investigation of bioterrorism.

    PubMed

    Budowle, Bruce; Beaudry, Jodi A; Barnaby, Neel G; Giusti, Alan M; Bannan, Jason D; Keim, Paul

    2007-08-01

    The risk and threat of bioterrorism and biocrime have become a large concern and challenge for governments and society to enhance biosecurity. Law enforcement plays an important role in assessing and investigating activities involved in an event of bioterrorism or biocrime. Key to a successful biosecurity program is increased awareness and early detection of threats facilitated by an integrated network of responsibilities and capabilities from government, academic, private, and public assets. To support an investigation, microbial forensic sciences are employed to analyze and characterize forensic evidence with the goal of attribution or crime scene reconstruction. Two different molecular biology-based assays--real time polymerase chain reaction (PCR) and repetitive element PCR--are described and demonstrate how molecular biology tools may be utilized to aid in the investigative process. Technologies relied on by microbial forensic scientists need to be properly validated so that the methods used are understood and so that interpretation of results is carried out within the limitations of the assays. The three types of validation are preliminary, developmental, and internal. The first is necessary for rapid response when a threat is imminent or an attack has recently occurred. The latter two apply to implementation of routinely used procedures. PMID:17696298

  2. [Effect of plant polysaccharides on TH1-dependent immune response: screening investigation].

    PubMed

    Danilets, M G; Bel'skiĭ, Iu P; Gur'ev, A M; Belousov, M V; Bel'skaia, N V; Trofimova, E S; Uchasova, E G; Alhmedzhanov, R R; Ligacheva, A A; Iusbov, M S; Agefonov, V I

    2010-06-01

    We have studied the influence of water-soluble polysaccharides isolated from Tussilago farfara L. leaves, Betula verrucosa Ehrh. leaves, Calendula officinalis L. flowers, Acorus calamus rhizomes, Inula helenium L. rhizomes, overground part of Trifolium pretense L., and overground part ofArtemisia absinthium L., on Thl immune response induced by sheep red blood cells and on NO production by murine peritoneal macrophages in vitro. All the investigated polysaccharides have stimulated a Th1 response. Polysaccharides isolated from Betula verrucosa leaves did not influence NO synthesis, while polysaccharides of Tussilago farfara leaves and Acorus calamus rhizomes stimulated NO synthase of murine macrophages on a level comparable with that of lipopolysaccharides (LPS). Polysaccharides from Inula helenium rhizomes, Calendula officinalis flowers, and overground parts of Trifolium pretense and Artemisia absinthium also stimulated NO production, but to a lower extent in comparison to LPS. PMID:20726346

  3. The effects of corporate social responsibility on employees' affective commitment: a cross-cultural investigation.

    PubMed

    Mueller, Karsten; Hattrup, Kate; Spiess, Sven-Oliver; Lin-Hi, Nick

    2012-11-01

    This study investigated the moderating effects of several Global Leadership and Organizational Behavior Effectiveness (GLOBE) cultural value dimensions on the relationship between employees' perceptions of their organization's social responsibility and their affective organizational commitment. Based on data from a sample of 1,084 employees from 17 countries, results showed that perceived corporate social responsibility (CSR) was positively related to employees' affective commitment (AC), after controlling for individual job satisfaction and gender as well as for nation-level differences in unemployment rates. In addition, several GLOBE value dimensions moderated the effects of CSR on AC. In particular, perceptions of CSR were more positively related to AC in cultures higher in humane orientation, institutional collectivism, ingroup collectivism, and future orientation and in cultures lower in power distance. Implications for future CSR research and cross-cultural human resources management are discussed.

  4. Responses of captive aye-ayes (Daubentonia madagascariensis) to the scent of conspecifics: a preliminary investigation.

    PubMed

    Price, E C; Feistner, A T

    1994-01-01

    The ability of 6 captive aye-ayes (Daubentonia madagascariensis) to discriminate scents from conspecifics of different age-sex classes was tested. The animals were presented with either unscented logs or logs that had been placed in: (1) their own cage, (2) the cages of adult males or (3) the cages of adult females with female offspring. Responses to the logs, measured by approaching, proximity, tapping, gnawing, sniffing, scent marking and vocalizations, were recorded for 30 min following presentation. Logs from females with offspring provoked the highest responses, and immature aye-ayes investigated logs more than adults of either sex. These results suggest that, as in many other prosimians, olfaction plays an important role in the communication systems of aye-ayes. PMID:7721204

  5. The effects of corporate social responsibility on employees' affective commitment: a cross-cultural investigation.

    PubMed

    Mueller, Karsten; Hattrup, Kate; Spiess, Sven-Oliver; Lin-Hi, Nick

    2012-11-01

    This study investigated the moderating effects of several Global Leadership and Organizational Behavior Effectiveness (GLOBE) cultural value dimensions on the relationship between employees' perceptions of their organization's social responsibility and their affective organizational commitment. Based on data from a sample of 1,084 employees from 17 countries, results showed that perceived corporate social responsibility (CSR) was positively related to employees' affective commitment (AC), after controlling for individual job satisfaction and gender as well as for nation-level differences in unemployment rates. In addition, several GLOBE value dimensions moderated the effects of CSR on AC. In particular, perceptions of CSR were more positively related to AC in cultures higher in humane orientation, institutional collectivism, ingroup collectivism, and future orientation and in cultures lower in power distance. Implications for future CSR research and cross-cultural human resources management are discussed. PMID:23067337

  6. Ecology-centered experiences among children and adolescents: A qualitative and quantitative analysis

    NASA Astrophysics Data System (ADS)

    Orton, Judy

    The present research involved two studies that considered ecology-centered experiences (i.e., experiences with living things) as a factor in children's environmental attitudes and behaviors and adolescents' ecological understanding. The first study (Study 1) examined how a community garden provides children in an urban setting the opportunity to learn about ecology through ecology-centered experiences. To do this, I carried out a yearlong ethnographic study at an urban community garden located in a large city in the Southeastern United States. Through participant observations and informal interviews of community garden staff and participants, I found children had opportunities to learn about ecology through ecology-centered experiences (e.g., interaction with animals) along with other experiences (e.g., playing games, reading books). In light of previous research that shows urban children have diminished ecological thought---a pattern of thought that privileges the relationship between living things---because of their lack of ecology-centered experiences (Coley, 2012), the present study may have implications for urban children to learn about ecology. As an extension of Study 1, I carried out a second study (Study 2) to investigate how ecology-centered experiences contribute to adolescents' environmental attitudes and behaviors in light of other contextual factors, namely environmental responsibility support, ecological thought, age and gender. Study 2 addressed three research questions. First, does ecological thought---a pattern of thought that privileges the relationship between living things---predict environmental attitudes and behaviors (EAB)? Results showed ecological thought did not predict EAB, an important finding considering the latent assumptions of previous research about the relationship between these two factors (e.g., Brugger, Kaiser, & Roczen, 2011). Second, do two types of contextual support, ecology-centered experiences (i.e., experiences with

  7. Training rats to voluntarily dive underwater: investigations of the mammalian diving response.

    PubMed

    McCulloch, Paul F

    2014-01-01

    Underwater submergence produces autonomic changes that are observed in virtually all diving animals. This reflexly-induced response consists of apnea, a parasympathetically-induced bradycardia and a sympathetically-induced alteration of vascular resistance that maintains blood flow to the heart, brain and exercising muscles. While many of the metabolic and cardiorespiratory aspects of the diving response have been studied in marine animals, investigations of the central integrative aspects of this brainstem reflex have been relatively lacking. Because the physiology and neuroanatomy of the rat are well characterized, the rat can be used to help ascertain the central pathways of the mammalian diving response. Detailed instructions are provided on how to train rats to swim and voluntarily dive underwater through a 5 m long Plexiglas maze. Considerations regarding tank design and procedure room requirements are also given. The behavioral training is conducted in such a way as to reduce the stressfulness that could otherwise be associated with forced underwater submergence, thus minimizing activation of central stress pathways. The training procedures are not technically difficult, but they can be time-consuming. Since behavioral training of animals can only provide a model to be used with other experimental techniques, examples of how voluntarily diving rats have been used in conjunction with other physiological and neuroanatomical research techniques, and how the basic training procedures may need to be modified to accommodate these techniques, are also provided. These experiments show that voluntarily diving rats exhibit the same cardiorespiratory changes typically seen in other diving animals. The ease with which rats can be trained to voluntarily dive underwater, and the already available data from rats collected in other neurophysiological studies, makes voluntarily diving rats a good behavioral model to be used in studies investigating the central aspects of the

  8. Training rats to voluntarily dive underwater: investigations of the mammalian diving response.

    PubMed

    McCulloch, Paul F

    2014-11-12

    Underwater submergence produces autonomic changes that are observed in virtually all diving animals. This reflexly-induced response consists of apnea, a parasympathetically-induced bradycardia and a sympathetically-induced alteration of vascular resistance that maintains blood flow to the heart, brain and exercising muscles. While many of the metabolic and cardiorespiratory aspects of the diving response have been studied in marine animals, investigations of the central integrative aspects of this brainstem reflex have been relatively lacking. Because the physiology and neuroanatomy of the rat are well characterized, the rat can be used to help ascertain the central pathways of the mammalian diving response. Detailed instructions are provided on how to train rats to swim and voluntarily dive underwater through a 5 m long Plexiglas maze. Considerations regarding tank design and procedure room requirements are also given. The behavioral training is conducted in such a way as to reduce the stressfulness that could otherwise be associated with forced underwater submergence, thus minimizing activation of central stress pathways. The training procedures are not technically difficult, but they can be time-consuming. Since behavioral training of animals can only provide a model to be used with other experimental techniques, examples of how voluntarily diving rats have been used in conjunction with other physiological and neuroanatomical research techniques, and how the basic training procedures may need to be modified to accommodate these techniques, are also provided. These experiments show that voluntarily diving rats exhibit the same cardiorespiratory changes typically seen in other diving animals. The ease with which rats can be trained to voluntarily dive underwater, and the already available data from rats collected in other neurophysiological studies, makes voluntarily diving rats a good behavioral model to be used in studies investigating the central aspects of the

  9. Numerical investigation of the seismo-acoustic responses of the Source Physics Experiment underground explosions

    NASA Astrophysics Data System (ADS)

    Antoun, T.; Ezzedine, S. M.; Vorobiev, O.; Glenn, L. A.

    2015-12-01

    We have performed three-dimensional high resolution simulations of underground explosions conducted recently in jointed rock outcrop as part of the Source Physics Experiment (SPE) being conducted at the Nevada National Security Site (NNSS). The main goal of the current study is to investigate the effects of the structural and geomechanical properties on the spall phenomena due to underground explosions and its subsequent effect on the seismo-acoustic signature at far distances. Two parametric studies have been undertaken to assess the impact of different 1) conceptual geological models including a single layer and two layers model, with and without joints and with and without varying geomechanical properties, and 2) depth of bursts of the explosions and explosion yields. Through these investigations we have explored not only the near-field response of the explosions but also the far-field responses of the seismic and the acoustic signatures. The near-field simulations were conducted using the Eulerian and Lagrangian codes, GEODYN and GEODYN -L, respectively, while the far-field seismic simulations were conducted using the elastic wave propagation code, WPP, and the acoustic response using the Kirchhoff-Helmholtz-Rayleigh time-dependent approximation code, KHR. Though a series of simulations, we have recorded the velocity field histories a) at the ground surface on an acoustic-source-patch for the acoustic simulations, and 2) on a seismic-source-box for the seismic simulations. We first analyzed the SPE3 and SPE4-prime experimental data and simulated results, and then simulated SPE5, SPE6/7 to anticipate their seismo-acoustic responses given conditions of uncertainties. SPE experiments were conducted in a granitic formation; we have extended the parametric study to include other geological settings such dolomite and alluvial formations. These parametric studies enabled us 1) investigating the geotechnical and geophysical key parameters that impact the seismo

  10. Fire Burnthrough Response of CFRP Aerostructures. Numerical Investigation and Experimental Verification

    NASA Astrophysics Data System (ADS)

    Sikoutris, Dimitris E.; Vlachos, Dimitris E.; Kostopoulos, Vassilis; Jagger, Stuart; Ledin, Stefan

    2012-04-01

    Aircraft structures are designed to withstand further to dynamic mechanical loadings thermal loads too. In the event of an external fire (while the aircraft is on the ground) the fuselage structure has to withstand and delay fire penetration. Prolonged burnthrough time is the design target. In the current work, a progressive fire-degradation material model is developed that links decomposition kinetics with the thermophysical properties of polymer composite materials. The material model is then implemented in a FE model to simulate the response of the flat panels under fire burnthrough conditions. Experimental investigation is performed in accordance to the ISO2685:1998 (E) Standard.

  11. Ecological effects of environmental change.

    PubMed

    Luque, Gloria M; Hochberg, Michael E; Holyoak, Marcel; Hossaert, Martine; Gaill, Françoise; Courchamp, Franck

    2013-05-01

    This Special Issue of Ecology Letters presents contributions from an international meeting organised by Centre National de la Recherche Scientifique (CNRS) and Ecology Letters on the broad theme of ecological effects of global environmental change. The objectives of these articles are to synthesise, hypothesise and illustrate the ecological effects of environmental change drivers and their interactions, including habitat loss and fragmentation, pollution, invasive species and climate change. A range of disciplines is represented, including stoichiometry, cell biology, genetics, evolution and biodiversity conservation. The authors emphasise the need to account for several key ecological factors and different spatial and temporal scales in global change research. They also stress the importance of ecosystem complexity through approaches such as functional group and network analyses, and of mechanisms and predictive models with respect to environmental responses to global change across an ecological continuum: population, communities and ecosystems. Lastly, these articles provide important insights and recommendations for environmental conservation and management, as well as highlighting future research priorities.

  12. Initial In Vitro Investigation of the Human Immune Response to Corneal Cells from Genetically Engineered Pigs

    PubMed Central

    Koike, Naoko; Long, Cassandra; Piluek, Jordan; Roh, Danny S.; SundarRaj, Nirmala; Funderburgh, James L.; Mizuguchi, Yoshiaki; Isse, Kumiko; Phelps, Carol J.; Ball, Suyapa F.; Ayares, David L.; Cooper, David K. C.

    2011-01-01

    Purpose. To compare the in vitro human humoral and cellular immune responses to wild-type (WT) pig corneal endothelial cells (pCECs) with those to pig aortic endothelial cells (pAECs). These responses were further compared with CECs from genetically engineered pigs (α1,3-galactosyltransferase gene-knockout [GTKO] pigs and pigs expressing a human complement-regulatory protein [CD46]) and human donors. Methods. The expression of Galα1,3Gal (Gal), swine leukocyte antigen (SLA) class I and class II on pCECs and pAECs, with or without activation by porcine IFN-γ, was tested by flow cytometry. Pooled human serum was used to measure IgM/IgG binding to and complement-dependent cytotoxicity (CDC) to cells from WT, GTKO, and GTKO/CD46 pigs. The human CD4+ T-cell response to cells from WT, GTKO, GTKO/CD46 pigs and human was tested by mixed lymphocyte reaction (MLR). Results. There was a lower level of expression of the Gal antigen and of SLA class I and II on the WT pCECs than on the WT pAECs, resulting in less antibody binding and reduced human CD4+ T-cell proliferation. However, lysis of the WT pCECs was equivalent to that of the pAECs, suggesting more susceptibility to injury. There were significantly weaker humoral and cellular responses to the pCECs from GTKO/CD46 pigs compared with the WT pCECs, although the cellular response to the GTKO/CD46 pCECs was greater than to the human CECs. Conclusions. These data provide the first report of in vitro investigations of CECs from genetically engineered pigs and suggest that pig corneas may provide an acceptable alternative to human corneas for clinical transplantation. PMID:21596821

  13. Effect of thiram and of a hydrocarbon mixture on freshwater macroinvertebrate communities in outdoor stream and pond mesocosms: II. Biological and ecological trait responses and leaf litter breakdown.

    PubMed

    Bayona, Yannick; Roucaute, Marc; Cailleaud, Kevin; Lagadic, Laurent; Bassères, Anne; Caquet, Thierry

    2015-11-01

    Higher-tier ecological risk assessment of chemicals often relies upon studies in dynamic and/or static mesocosms. Physico-chemical and hydrological properties of each type of mesocosm result in specific chemicals fate, community functioning, and potential recovery. In the present study, macroinvertebrate abundance- and biomass-weighted biological and ecological trait matrices were used to assess the effects of a dithiocarbamate fungicide, thiram (35 and 170 µg l(-1)), and of a petroleum middle distillate (0.01, 0.4, 2 and 20 mg l(-1)) in outdoor stream and pond mesocosms. Trait sensitivity was characterized using functional diversity indices and trait modality distributions to assess the influence of the type of experimental systems and the ability of traits to disentangle chemical-induced effects from temporal and stochastic variations. In addition, leaf litter breakdown was used as an integrative functional endpoint. Regardless to the substance, treatments had a direct effect on the functional structure of benthic macroinvertebrate communities in streams but not in ponds, suggesting that global functional responses to chemicals are system-specific. Although both substances had an effect in streams, differences were noticed in the nature of the affected traits suggesting that chemical mode of action plays a role in functional alterations. This was illustrated by the link between negative effects of chemical exposure on detritivorous taxa and reduced litter breakdown rate in streams. Therefore, characterisation of macroinvertebrate biological traits associated with the measurement of a functional process such as litter breakdown may provide a comprehensive understanding of the effects occurring in mesocosms exposed to organic chemicals.

  14. Effect of thiram and of a hydrocarbon mixture on freshwater macroinvertebrate communities in outdoor stream and pond mesocosms: II. Biological and ecological trait responses and leaf litter breakdown.

    PubMed

    Bayona, Yannick; Roucaute, Marc; Cailleaud, Kevin; Lagadic, Laurent; Bassères, Anne; Caquet, Thierry

    2015-11-01

    Higher-tier ecological risk assessment of chemicals often relies upon studies in dynamic and/or static mesocosms. Physico-chemical and hydrological properties of each type of mesocosm result in specific chemicals fate, community functioning, and potential recovery. In the present study, macroinvertebrate abundance- and biomass-weighted biological and ecological trait matrices were used to assess the effects of a dithiocarbamate fungicide, thiram (35 and 170 µg l(-1)), and of a petroleum middle distillate (0.01, 0.4, 2 and 20 mg l(-1)) in outdoor stream and pond mesocosms. Trait sensitivity was characterized using functional diversity indices and trait modality distributions to assess the influence of the type of experimental systems and the ability of traits to disentangle chemical-induced effects from temporal and stochastic variations. In addition, leaf litter breakdown was used as an integrative functional endpoint. Regardless to the substance, treatments had a direct effect on the functional structure of benthic macroinvertebrate communities in streams but not in ponds, suggesting that global functional responses to chemicals are system-specific. Although both substances had an effect in streams, differences were noticed in the nature of the affected traits suggesting that chemical mode of action plays a role in functional alterations. This was illustrated by the link between negative effects of chemical exposure on detritivorous taxa and reduced litter breakdown rate in streams. Therefore, characterisation of macroinvertebrate biological traits associated with the measurement of a functional process such as litter breakdown may provide a comprehensive understanding of the effects occurring in mesocosms exposed to organic chemicals. PMID:26311171

  15. Investigating Undergraduate Students' Science Literacy: Responses Related to Radiation and DNA

    NASA Astrophysics Data System (ADS)

    Impey, C.; Buxner, S.; Nieberding, M.; Romine, J.

    2015-11-01

    This study is part of a larger one investigating undergraduate students' science literacy. Over the past 25 years we have been investigating undergraduate students' basic science knowledge as well as beliefs and attitudes towards science and technology. Data has been collected from almost 12,000 students, mostly freshman and sophomore students and mostly non-STEM majors. This paper presents findings of two open ended questions that probe students' understanding of radiation and DNA. Each open ended question was coded using a scheme developed from existing literature and emergent themes. Analyses revealed that STEM students are better able to correctly describe radiation and had fewer misconceptions. Many students mentioned chemical characteristics and functions of DNA although a substantial number of students reported common misconceptions or trivial responses. Our results add to our existing work to help us understand how to better support students' learning in our undergraduate courses.

  16. 41 CFR 102-80.65 - What are Federal agencies' responsibilities concerning the investigation of incidents, such as...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... responsibilities concerning the investigation of incidents, such as fires, accidents, injuries, and environmental... agencies' responsibilities concerning the investigation of incidents, such as fires, accidents, injuries, and environmental incidents? 102-80.65 Section 102-80.65 Public Contracts and Property...

  17. The "Hamburger Connection" as Ecologically Unequal Exchange: A Cross-National Investigation of Beef Exports and Deforestation in Less-Developed Countries

    ERIC Educational Resources Information Center

    Austin, Kelly

    2010-01-01

    This study explores Norman Myers's concept of the "hamburger connection" as a form of ecologically unequal exchange, where more-developed nations are able to transfer the environmental costs of beef consumption to less-developed nations. I used ordinary least squares (OLS) regression to test whether deforestation in less-developed nations is…

  18. Application of Spectral Ratio Methods to an Investigation of Site Response in the Los Angeles Basin

    NASA Astrophysics Data System (ADS)

    Ng, R.; Polet, J.

    2015-12-01

    It is well established that sedimentary basins can increase the amplification and duration of earthquake ground motion. Past earthquakes have shown that site effects have a major influence on seismic damage and loss in urban areas. However, the response at any given site can vary significantly, even within the LA basin. We aim to investigate site response within the LA Basin through the application of the Horizontal-to-Vertical (H/V) spectral ratio method. This method was applied to 3-component broadband waveforms from the Los Angeles Syncline Seismic Interferometry Experiment (LASSIE). LASSIE is a collaborative, temporary, and dense array of 73 broadband seismometers that were active for a two month period starting October 2014 until November 2014, transecting the Los Angeles basin from Long Beach to La Puente. We use the Geopsy software to measure the fundamental frequency and minimum site amplification at each station. Data analysis and interpretation were conducted in accordance to the Site Effects Assessment Using Ambient Excitations (SESAME) guidelines for implementing the H/V ratio technique for investigations of site effects. Results from our initial data analysis indicate an average fundamental period at the basin center of 6 s - 12 s and peaks in the spectral ratio curves at much shorter periods for sites the basin edge of. We will show maps of the amplification and fundamental frequencies based on our spectral ratio analysis of the LASSIE data and compare our results with damage patterns of historic earthquakes, as well as models of the LA basin.

  19. Experimental and numerical investigation on the dynamic response of pile group in liquefying ground

    NASA Astrophysics Data System (ADS)

    Tang, Liang; Zhang, Xiaoyu; Ling, Xianzhang; Li, Hui; Ju, Nengpan

    2016-03-01

    The response of pile foundation in liquefiable sand reinforced by densification techniques remains a very complex problem during strong earthquakes. A shake-table experiment was carried out to investigate the behavior of a reinforced concrete low-cap pile group embedded in this type of ground. In this study, a three-dimensional (3D) finite element (FE) analysis of the experiment was conducted. The computed response of the soil-pile system was in reasonable agreement with the experimental results, highlighting some key characteristics. Then, a parametric study was performed to explore the influence of pile spacing, pile stiffness ( EI), superstructure mass, sand permeability, and shaking characteristics of input motion on the behavior of the pile. The investigation demonstrated a stiffening behavior appearing in the liquefied mediumdense sand, and the pile group effect seemed negligible. Furthermore, the kinematic effect was closely connected with both EI and sand permeability. Nevertheless, the inertial effect was strongly influenced by the superstructure mass. Meanwhile, high frequency and large amplitude of the input motion could produced greater the pile's moments. It is estimated that this case study could further enhance the current understanding of the behavior of low-cap pile foundations in liquefied dense sand.

  20. Investigation of self-help oil-spill response techniques and equipment

    SciTech Connect

    Enderlin, W I; Downing, J P; Enderlin, C W; Sanquist, T F; Pope, W S

    1992-06-01

    The US Coast Guard commissioned Pacific Northwest Laboratory (PNL) to conduct this study of 45 self-help oil-spill response techniques and equipment for oceangoing tankers and inland tank barges to assess the potential effectiveness of the proposed countermeasure categories. This study considers the hypothetical outflow of oil in the case of side damage and bottom damage to single-hull designs. The results will be considered by the Coast Guard in drafting regulations pertaining to the requirement for tanker vessels to carry oil pollution response equipment (i.e., in response to the oil Pollution Act of 1990). PNL's approach to this investigation included: assessing time-dependent oil outflow in the cases of collision and grounding of both tankers and barges; identifying environmental constraints on self-help countermeasure operation; identifying human factor issues, such as crew performance, safety, and training requirements for the self-help countermeasures considered; and assessing each self-help countermeasure with respect to its potential for minimizing oil loss to the environment. Results from the time-dependent oil outflow, environmental limitations, and human factors requirements were input into a simulation model.

  1. Transcranial modulation of brain oscillatory responses: A concurrent tDCS-MEG investigation.

    PubMed

    Hanley, Claire J; Singh, Krish D; McGonigle, David J

    2016-10-15

    Despite the increasing use of transcranial direct current stimulation (tDCS), the physiological mechanisms underlying its effects are still largely unknown. One approach to directly investigate the effects of the neuromodulation technique on the brain is to integrate tDCS with non-invasive neuroimaging in humans. To provide new insight into the neurobiology of the method, DC stimulation (1mA, 600s) was applied concurrently with Magnetoencephalography (MEG), while participants engaged in a visuomotor task before, during and after a period of tDCS. Responses in the motor beta band (15-30Hz) and visual gamma band (30-80Hz) were localised using Synthetic Aperture Magnetometry (SAM). The resulting induced and evoked oscillatory responses were subsequently analysed. A statistically significant reduction of average power in the visual gamma band was observed for anodal compared to sham stimulation. The magnitude of motor evoked responses was also found to be significantly modulated by anodal stimulation. These results demonstrate that MEG can be used to derive inferences on the cortical mechanisms of tDCS.

  2. Investigation of negative BOLD responses in human brain through NIRS technique. A visual stimulation study.

    PubMed

    Maggioni, Eleonora; Molteni, Erika; Zucca, Claudio; Reni, Gianluigi; Cerutti, Sergio; Triulzi, Fabio M; Arrigoni, Filippo; Bianchi, Anna M

    2015-03-01

    Despite negative blood oxygenation level dependent (BOLD) responses to visual stimuli have recently gained considerable interest, the explanation for their underlying neuronal and vascular mechanisms is still controversial. In the present study, a multimodal experimental approach is presented to shed light on the negative BOLD phenomenon in the human brain. In particular, information from functional magnetic resonance imaging (fMRI) and near infrared spectroscopy (NIRS) was integrated to confirm and gain insight into the phenomenon of negative BOLD responses (NBRs) to unpatterned intermittent photic stimulation (IPS) in healthy subjects. Eight healthy subjects participated in the study. Consistent findings emerged from the activation analysis of fMRI and NIRS data and the comparison of BOLD and hemoglobin responses at the single channel level showed that NBRs are related to a decrease in oxyhemoglobin (HbO) combined with a lower increase in deoxyhemoglobin (HHb), corresponding to a decrease in total hemoglobin (THb) and estimated cerebral blood volume (CBV). The HbO and HHb variations were significant in at least one channel in six subjects out of eight (p<0.05). The NIRS technique allowed obtaining valuable information on the vascular determinants of the NBRs, since the discrimination between HbO, HHb and THb information provided a more comprehensive view of the negative BOLD phenomenon. The within and between subject heterogeneous BOLD-Hb temporal relations pave the way to further investigations into the neurovascular properties of NBRs.

  3. A numerical and experimental investigation of premixed methane-air flame transient response

    SciTech Connect

    Habib N. Najm; Phillip H. Paul; Omar M. Knio; Andrew McIlroy

    2000-01-06

    The authors report the results of a numerical and experimental investigation of the response of premixed methane-air flames to transient strain-rate disturbances induced by a two-dimensional counter-rotating vortex-pair. The numerical and experimental time histories of flow and flame evolution are matched over a 10 ms interaction time. Measurements and computations of CH and OH peak data evolution are reported, and found to indicate mis-prediction of the flame time scales in the numerical model. Qualitative transient features of OH at rich conditions are not predicted in the computations. On the other hand, evolution of computed and measured normalized HCO fractions are in agreement. The computed CH{sub 3}O response exhibits a strong transient driven by changes to internal flame structure, namely temperature profile steepening, induced by the flow field. Steady state experimental PLIF CH{sub 3}O data is reported, but experimental transient CH{sub 3}O data is not available. The present analysis indicates that the flame responds at time scales that are quite distinct from ``propagation'' time scale derived from flame thickness and burning speed. Evidently, these propagation time scales are not adequate for characterizing the transient flame response.

  4. Behavioral and electrophysiological investigation of semantic and response conflict in the Stroop task.

    PubMed

    Augustinova, Maria; Silvert, Laetitia; Ferrand, Ludovic; Llorca, Pierre Michel; Flaudias, Valentin

    2015-04-01

    By combining the semantic Stroop paradigm (e.g., Klein in American Journal of Psychology 77:576-588, 1964) with a single-letter coloring (SLC) procedure (e.g., Besner et al. in Psychonomic Bulletin & Review 4:221-225, 1997), this research investigated whether the frequently reported Stroop-related event-related potential (ERP) effect arising about 400 ms after stimulus onset (Ninc) is sensitive to the semantic and/or the response conflict. Consistent with our past findings (e.g., Augustinova et al. in Psychonomic Bulletin & Review 17:827-833, 2010), SLC speeded up reaction times for standard-incongruent items only, indicating that SLC reduced the response conflict that these (but not color-associated and neutral) items involve. Ninc amplitudes were more negative for standard-incongruent and color-associated than for color-neutral items. Importantly, this difference was not modulated by SLC. Hence, the behavioral and ERP results conjointly suggest that the Stroop-related Ninc is sensitive to semantic rather than to response and/or general conflict.

  5. Mechanical investigations of sound-induced responses in a simple ear

    NASA Astrophysics Data System (ADS)

    Nowotny, Manuela; Hummel, Jennifer; Kössl, Manfred; Udayashankar, Arun Palghat; Wolf, Konstantin

    2015-12-01

    Previous in-vivo studies have shown that the tonotopically-organized hearing organ, the crista acustica, of the bushcricket Mecopoda elongata is a promising model for investigations of basic hearing mechanics. This linearly arranged organ with a length of <1 mm consists of about 45 receptor units and processes frequencies from about 4 up to at least 80 kHz. Pure-tone stimulation of the crista acustica leads to travelling waves along the longitudinal axis of the hearing organ. We found that the amplitude maximum of the sound-induced travelling waves is shifted in the radial direction during the propagation of the travelling wave. The overall amplitude maximum was found to be located always on one side (anterior) in respect to the transduction place. This mechanical biasing presumably optimizes the signal transduction. Additionally, the amplitude response maximum of the travelling wave during one cycle of motion exhibits different degrees in the radial shift. During broad-band noise stimulation, the mechanical response of the crista acustica exhibits a low-frequency dominance. When using the conspecific chirp of M. elongata (2-90 kHz), as stimulus frequencies above 30 kHz do not lead to large responses even though the hearing organ is able to detect frequencies up to at least 80 kHz, covering the frequency range of the chirp with its amplitude maximum at about 70 kHz.

  6. An fMRI investigation of responses to peer rejection in adolescents with autism spectrum disorders

    PubMed Central

    Masten, Carrie L.; Colich, Natalie L.; Rudie, Jeffrey D.; Bookheimer, Susan Y.; Eisenberger, Naomi I.; Dapretto, Mirella

    2011-01-01

    Peer rejection is particularly pervasive among adolescents with autism spectrum disorders (ASD). However, how adolescents with ASD differ from typically developing adolescents in their responses to peer rejection is poorly understood. The goal of the current investigation was to examine neural responses to peer exclusion among adolescents with ASD compared to typically developing adolescents. Nineteen adolescents with ASD and 17 typically developing controls underwent fMRI as they were ostensibly excluded by peers during an online game called Cyberball. Afterwards, participants reported their distress about the exclusion. Compared to typically developing adolescents, those with ASD displayed less activity in regions previously linked with the distressing aspect of peer exclusion, including the subgenual anterior cingulate and anterior insula, as well as less activity in regions previously linked with the regulation of distress responses during peer exclusion, including the ventrolateral prefrontal cortex and ventral striatum. Interestingly, however, both groups self-reported equivalent levels of distress. This suggests that adolescents with ASD may engage in differential processing of social experiences at the neural level, but be equally aware of, and concerned about, peer rejection. Overall, these findings contribute new insights about how this population may differentially experience negative social events in their daily lives. PMID:22318914

  7. Study of the succession of microbial communities for sulfur cycle response to ecological factors change in sediment of sewage system.

    PubMed

    Liu, Yanchen; Dong, Qian; Wu, Chen; Zhou, Xiaohong; Shi, Hanchang

    2015-06-01

    The biological reaction process of sulfur in biofilms and sediments causes serious problems of corrosion and odor in sewage systems. This study aims to reveal the distribution and shift of microbial diversity that survives inside the sediment in response to surrounding changes in sewage systems. The successions of microbial community were compared via denaturing gradient gel electrophoresis and by constructing phylogenetic trees via maximum likelihood method. The results indicated that the shift of microbial diversity is not significant along the vertical layer inside the sediment. The influences of sediment accumulation time on the shift in microbial diversity are evident, particularly with the switch of the accumulation stage. Implementing a control strategy for oxygen injection and nitrate addition evidently inhibits and stimulates some dominant sulfate-reducing bacterial strains in the sediment. The diversity in the total bacteria is positively related with ORP, dissolved oxygen, and sulfide concentration. PMID:25592909

  8. Physiological and Proteomic Investigations to Study the Response of Tomato Graft Unions under Temperature Stress

    PubMed Central

    Muneer, Sowbiya; Ko, Chung Ho; Wei, Hao; Chen, Yuze; Jeong, Byoung Ryong

    2016-01-01

    Background Grafting is an established practice for asexual propagation in horticultural and agricultural crops. The study on graft unions has become of interest for horticulturists using proteomic and genomic techniques to observe transfer of genetic material and signal transduction pathways from root to shoot and shoot to root. Another reason to study the graft unions was potentially to observe resistance against abiotic stresses. Using physiological and proteomic analyses, we investigated graft unions (rootstock and scions) of tomato genotypes exposed to standard-normal (23/23 and 25/18°C day/night) and high-low temperatures (30/15°C day/night). Results Graft unions had varied responses to the diverse temperatures. High-low temperature, but not standard-normal temperature, induced the production of reactive oxygen species (ROS) in the form of H2O2 and O2-1 in rootstock and scions. However, the expression of many cell protection molecules was also induced, including antioxidant enzymes and their immunoblots, which also show an increase in their activities such as superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX). The graft interfaces thus actively defend against stress by modifying their physiological and proteomic responses to establish a new cellular homeostasis. As a result, many proteins for cellular defense were regulated in graft unions under diverse temperature, in addition to the regulation of photosynthetic proteins, ion binding/transport proteins, and protein synthesis. Moreover, biomass, hardness, and vascular transport activity were evaluated to investigate the basic connectivity between rootstock and scions. Conclusions Our study provides physiological evidence of the grafted plants’ response to diverse temperature. Most notably, our study provides novel insight into the mechanisms used to adapt the diverse temperature in graft unions (rootstock/scion). PMID:27310261

  9. Seismic response of rock slopes: Numerical investigations on the role of internal structure

    NASA Astrophysics Data System (ADS)

    Arnold, L.; Applegate, K.; Gibson, M.; Wartman, J.; Adams, S.; Maclaughlin, M.; Smith, S.; Keefer, D. K.

    2013-12-01

    The stability of rock slopes is significantly influenced and often controlled by the internal structure of the slope created by such discontinuities as joints, shear zones, and faults. Under seismic conditions, these discontinuities influence both the resistance of a slope to failure and its response to dynamic loading. The dynamic response, which can be characterized by the slope's natural frequency and amplification of ground motion, governs the loading experienced by the slope in a seismic event and, therefore, influences the slope's stability. In support of the Network for Earthquake Engineering Simulation (NEES) project Seismically-Induced Rock Slope Failure: Mechanisms and Prediction (NEESROCK), we conducted a 2D numerical investigation using the discrete element method (DEM) coupled with simple discrete fracture networks (DFNs). The intact rock mass is simulated with a bonded assembly of discrete particles, commonly referred to as the bonded-particle model (BPM) for rock. Discontinuities in the BPM are formed by the insertion of smooth, unbonded contacts along specified planes. The influence of discontinuity spacing, orientation, and stiffness on slope natural frequency and amplification was investigated with the commercially available Particle Flow Code (PFC2D). Numerical results indicate that increased discontinuity spacing has a non-linear effect in decreasing the amplification and increasing the natural frequency of the slope. As discontinuity dip changes from sub-horizontal to sub-vertical, the slope's level of amplification increases while the natural frequency of the slope decreases. Increased joint stiffness decreases amplification and increases natural frequency. The results reveal that internal structure has a strong influence on rock slope dynamics that can significantly change the system's dynamic response and stability during seismic loading. Financial support for this research was provided by the United States National Science Foundation (NSF

  10. Phenological assessment in the Owhyee Uplands: integrating climate drivers and ecological response at local to regional scales

    NASA Astrophysics Data System (ADS)

    Torregrosa, A.; Hanser, S.; Tumbusch, M. L.; Bedford, D.

    2009-12-01

    The seasonal cycle of vegetation change in biomass, structure, and composition is a dominant landscape feature influencing many ecosystem components of the Owyhee Uplands particularly resident and migratory vertebrates and invertebrates. Encompassing portions of Idaho, Nevada, and Oregon, the Owyhee Uplands have remained relatively intact with climate, exotic plant invasions, and anthropogenic agents, such as grazing, acting as the principle causes of ecosystem stress. The sagebrush habitats of the Owyhee Uplands are a stronghold for several federal and state species of special concern, including the Greater sage-grouse (Centrocercus urophasianus). We examined phenological variation in response to climate conditions such as temperature, relative humidity, precipitation, soil moisture, solar irradiance, and snowfall at a range of spatial and temporal scales across a gradient of soil and landforms. We integrated/analyzed measures of greenness derived from ground-based cameras and several satellite sensors (AVHRR, MODIS, and Landsat), early and late season field-collected measures of plant species cover and passerine bird diversity and abundance, daily measurement of soil moisture conditions from in-situ sensors, site-level snow depth conditions from thermochron fitted snow poles, and climate conditions derived from a combination of site-based meteorological stations and interpolated PRISM data. Our objectives include 1) quantifying covariation between greenness-climate-soil-snow conditions and vertebrate and plant species phenology, 2) spatial interscale comparisons of the covariation, and 3) recommendations for on-going data collection and analysis methods to explore phenological response within the context of the natural range of variability and under climate change scenarios.

  11. Ecological niche

    SciTech Connect

    Shugart, H.H.

    1980-01-01

    The ecological niche of an organism is the set of environmental conditions under which the particular functions of the organism could be expected to assure its survival. It comprises both the set of conditions where the organism lives (often termed the habitat of the organism) and the functional role of the organism in the ecosystem. Recent works in niche theory have enabled ecologists to develop predictions and actual applications. The history of the niche concept, applications of niche theory, and ecological differences between similar species are discussed.

  12. Acid-base physiology response to ocean acidification of two ecologically and economically important holothuroids from contrasting habitats, Holothuria scabra and Holothuria parva.

    PubMed

    Collard, Marie; Eeckhaut, Igor; Dehairs, Frank; Dubois, Philippe

    2014-12-01

    Sea cucumbers are dominant invertebrates in several ecosystems such as coral reefs, seagrass meadows and mangroves. As bioturbators, they have an important ecological role in making available calcium carbonate and nutrients to the rest of the community. However, due to their commercial value, they face overexploitation in the natural environment. On top of that, occurring ocean acidification could impact these organisms, considered sensitive as echinoderms are osmoconformers, high-magnesium calcite producers and have a low metabolism. As a first investigation of the impact of ocean acidification on sea cucumbers, we tested the impact of short-term (6 to 12 days) exposure to ocean acidification (seawater pH 7.7 and 7.4) on two sea cucumbers collected in SW Madagascar, Holothuria scabra, a high commercial value species living in the seagrass meadows, and H. parva, inhabiting the mangroves. The former lives in a habitat with moderate fluctuations of seawater chemistry (driven by day-night differences) while the second lives in a highly variable intertidal environment. In both species, pH of the coelomic fluid was significantly negatively affected by reduced seawater pH, with a pronounced extracellular acidosis in individuals maintained at pH 7.7 and 7.4. This acidosis was due to an increased dissolved inorganic carbon content and pCO2 of the coelomic fluid, indicating a limited diffusion of the CO2 towards the external medium. However, respiration and ammonium excretion rates were not affected. No evidence of accumulation of bicarbonate was observed to buffer the coelomic fluid pH. If this acidosis stays uncompensated for when facing long-term exposure, other processes could be affected in both species, eventually leading to impacts on their ecological role.

  13. Investigating the Autonomic Nervous System Response to Anxiety in Children with Autism Spectrum Disorders

    PubMed Central

    Kushki, Azadeh; Drumm, Ellen; Pla Mobarak, Michele; Tanel, Nadia; Dupuis, Annie; Chau, Tom; Anagnostou, Evdokia

    2013-01-01

    Assessment of anxiety symptoms in autism spectrum disorders (ASD) is a challenging task due to the symptom overlap between the two conditions as well as the difficulties in communication and awareness of emotions in ASD. This motivates the development of a physiological marker of anxiety in ASD that is independent of language and does not require observation of overt behaviour. In this study, we investigated the feasibility of using indicators of autonomic nervous system (ANS) activity for this purpose. Specially, the objectives of the study were to 1) examine whether or not anxiety causes significant measurable changes in indicators of ANS in an ASD population, and 2) characterize the pattern of these changes in ASD. We measured three physiological indicators of the autonomic nervous system response (heart rate, electrodermal activity, and skin temperature) during a baseline (movie watching) and anxiety condition (Stroop task) in a sample of typically developing children (n = 17) and children with ASD (n = 12). The anxiety condition caused significant changes in heart rate and electrodermal activity in both groups, however, a differential pattern of response was found between the two groups. In particular, the ASD group showed elevated heart rate during both baseline and anxiety conditions. Elevated and blunted phasic electrodermal activity were found in the ASD group during baseline and anxiety conditions, respectively. Finally, the ASD group did not show the typical decrease in skin temperature in response to anxiety. These results suggest that 1) signals of the autonomic nervous system may be used as indicators of anxiety in children with ASD, and 2) ASD may be associated with an atypical autonomic response to anxiety that is most consistent with sympathetic over-arousal and parasympathetic under-arousal. PMID:23577072

  14. Investigating the autonomic nervous system response to anxiety in children with autism spectrum disorders.

    PubMed

    Kushki, Azadeh; Drumm, Ellen; Pla Mobarak, Michele; Tanel, Nadia; Dupuis, Annie; Chau, Tom; Anagnostou, Evdokia

    2013-01-01

    Assessment of anxiety symptoms in autism spectrum disorders (ASD) is a challenging task due to the symptom overlap between the two conditions as well as the difficulties in communication and awareness of emotions in ASD. This motivates the development of a physiological marker of anxiety in ASD that is independent of language and does not require observation of overt behaviour. In this study, we investigated the feasibility of using indicators of autonomic nervous system (ANS) activity for this purpose. Specially, the objectives of the study were to 1) examine whether or not anxiety causes significant measurable changes in indicators of ANS in an ASD population, and 2) characterize the pattern of these changes in ASD. We measured three physiological indicators of the autonomic nervous system response (heart rate, electrodermal activity, and skin temperature) during a baseline (movie watching) and anxiety condition (Stroop task) in a sample of typically developing children (n = 17) and children with ASD (n = 12). The anxiety condition caused significant changes in heart rate and electrodermal activity in both groups, however, a differential pattern of response was found between the two groups. In particular, the ASD group showed elevated heart rate during both baseline and anxiety conditions. Elevated and blunted phasic electrodermal activity were found in the ASD group during baseline and anxiety conditions, respectively. Finally, the ASD group did not show the typical decrease in skin temperature in response to anxiety. These results suggest that 1) signals of the autonomic nervous system may be used as indicators of anxiety in children with ASD, and 2) ASD may be associated with an atypical autonomic response to anxiety that is most consistent with sympathetic over-arousal and parasympathetic under-arousal.

  15. Comparative secretome investigation of Magnaporthe oryzae proteins responsive to nitrogen starvation.

    PubMed

    Wang, Yiming; Wu, Jingni; Park, Zee Yong; Kim, Sang Gon; Rakwal, Randeep; Agrawal, Ganesh Kumar; Kim, Sun Tae; Kang, Kyu Young

    2011-07-01

    Magnaporthe oryzae is a fungal pathogen that causes blast disease in rice. During its early infection process, during which starvation of nutrients, including nitrogen, prevails before establishment of successful infection, the fungally secreted proteins play an important role in the pathogenicity and stress response. In this study, M. oryzae-secreted proteins were investigated in an N-deficient minimal medium using two-dimensional gel electrophoresis (2-DGE) coupled with mass spectrometry analysis (MALDI-TOF-MS and μLC-ESI-MS/MS). The 2-DGE analysis of secreted proteins detected 89 differentially expressed protein spots (14 downregulated and 75 upregulated) responsive to N starvation. Eighty five of the protein spots were identified by mass spectrometry analyses. Identified proteins were mainly cell wall hydrolase enzymes (22.4%), protein and lipid hydrolases (24.7%), reactive oxygen species detoxifying proteins (22.4%), and proteins with unknown function (14.1%), suggesting early production of prerequisite proteins for successful infection of the host. SignalP analysis predicted the presence of signal peptides in 67% of the identified proteins, suggesting that in addition to the classical Golgi/endoplasmic reticulum secretory pathway, M. oryzae might possess other, as yet undefined, secretory pathways. Those nonclassical or leaderless secretion proteins accounted for 25.9% of the total identified proteins by TatP and SecretomeP predictions. Semiquantitative reverse transcriptase polymerase chain reaction of seven randomly selected N-responsive secreted proteins also revealed a good correlation between RNA and protein levels. Taken together, the establishment of the M. oryzae secretome that is responsive to N starvation provides the first evidence of the secretion of 60 unreported and 25 previously known proteins. This developed protein inventory could be exploited to improve our understanding of the secretory mechanisms of M. oryzae and its invasive growth

  16. Preliminary investigation into the design of thermally responsive Forster resonance energy transfer colloids

    NASA Astrophysics Data System (ADS)

    Bedford, Monte Scott

    While nuclear imaging techniques (Magnetic Resonance Imaging, Computed Tomography, and Positron Emission Tomography) have proven effective for diagnosis and treatment of disease in the human body, fluorescence-enhanced optical imaging offers additional benefits. Fluorescent imaging provides high resolution with real-time response, persistent lifetime (hours to days), cell targeting, and transdermal penetration with minimal physical encumbrance. Malignant cells can be targeted by absorbance of exogenous fluorescent nanoprobe contrast agents. Imaging is improved by fluorescent enhancement, especially by energy transfer between attached dyes. Also for use against cancer are heat-active treatments, such as hyperthermal, photothermal, and chemothermal therapies. Helpful to these treatments is the thermal response from nanoprobes, within human cells, which provide real-time feedback. The present study investigates the design and feasibility of a nanoprobe molecular device, absorbable into malignant human cells, which provides real-time tracking and thermal response, as indicated by enhanced fluorescence by energy transfer. A poly(propargyl acrylate) colloidal suspension was synthesized. The particles were modified with a triblock copolymer, previously shown to be thermally responsive, and an end-attached fluorescent dye. A second dye was modeled for attachment in subsequent work. When two fluorescent dyes are brought within sufficiently close proximity, and excitation light is supplied, energy can be transferred between dyes to give enhanced fluorescence with a large Stokes shift (increase in wavelength between excitation and emission). The dye pair was modeled for overlap of emission and absorbance wavelengths, and energy transfer was demonstrated with 23% efficiency and a 209 nm Stokes shift. The quantum yield of the donor dye was determined at 70%, and the distance for 50% energy transfer was calculated at 2.9 nm, consistent with reports for similar compounds. When

  17. On the slow decompressive response of volatile- and crystal-bearing magmas: An analogue experimental investigation

    NASA Astrophysics Data System (ADS)

    Spina, Laura; Cimarelli, Corrado; Scheu, Bettina; Di Genova, Danilo; Dingwell, Donald B.

    2016-01-01

    The degassing kinetics of ascending magma strongly affect eruption dynamics. The kinetics are in turn influenced by magma properties. The investigation of the relationship between magma properties and eruption dynamics is a key element in revealing the processes characterizing magmatic flows within the shallow conduit. To explore the effects of physical properties on degassing in basaltic eruptive systems, we have designed and carried out experiments on the slow decompressive response of analogue magmas, composed of silicone-oil-based suspensions, using a shock-tube apparatus. Four series of experiments were performed: 1) particle-free silicone oils with viscosity ranging from 1 to 1000 Pa s were used to constrain the liquid response; 2) silicone oils with variable proportion of suspended micrometric spherical particles were employed to assess the effect of different crystal fractions; 3) suspensions of elongated particles in silicone oils were used to investigate the role of crystal shape; 4) the effects of saturation time and pressure were examined. The rheology of both spherical- and elongated-particle-bearing suspensions were characterized by concentric cylinder rotational rheometry. The flow dynamics of the bubbly fluid, from the process of bubble nucleation up to the development of a permeable bubble network, were constrained using image analysis. Different fluid regimes were distinguished: (i) nucleation, (ii) foam build-up and (iii) foam oscillation. By comparing results obtained from the different series of experiments, we were able to assess the primary role played by the presence of particles on the evolution of the gas volume fraction within the samples. Particle fraction has a dominant role at high concentration, affecting the motion of the fluid. Finally, particle shape influences the long-term degassing efficiency of the fluid. Using scaling considerations, such observations are applied to mafic to intermediate systems. The results of our

  18. Can ecological history influence response to pollutants? Transcriptomic analysis of Manila clam collected in different Venice lagoon areas and exposed to heavy metal.

    PubMed

    Milan, Massimo; Matozzo, Valerio; Pauletto, Marianna; Di Camillo, Barbara; Giacomazzo, Matteo; Boffo, Luciano; Binato, Giovanni; Marin, Maria Gabriella; Patarnello, Tomaso; Bargelloni, Luca

    2016-05-01

    Chronic exposure to environmental pollutants can exert strong selective pressures on natural populations, favoring the transmission over generations of traits that enable individuals to survive and thrive in highly impacted environments. The lagoon of Venice is an ecosystem subject to heavy anthropogenic impact, mainly due to the industrial activities of Porto Marghera (PM), which led to a severe chemical contamination of soil, groundwater, and sediments. Gene expression analysis on wild Manila clams collected in different Venice lagoon areas enabled to identify differences in gene expression profiles between clams collected in PM and those sampled in clean areas, and the definition of molecular signatures of chemical stress. However, it remains largely unexplored to which extent modifications of gene expression patterns persists after removing the source of contamination. It is also relatively unknown whether chronic exposure to xenobiotics affects the response to other chemical pollutants. To start exploring such issues, in the present study a common-garden experiment was coupled with transcriptomic analysis, to compare gene expression profiles of PM clams with those of clams collected in the less impacted area of Chioggia (CH) during a period under the same control conditions. Part of the two experimental groups were also exposed to copper for seven days to assess whether different "ecological history" does influence response to such pollutant. The results obtained suggest that the chronic exposure to chemical pollution generated a response at the transcriptional level that persists after removal for the contaminated site. These transcriptional changes are centered on key biological processes, such as defense against either oxidative stress or tissue/protein damage, and detoxification, suggesting an adaptive strategy for surviving in the deeply impacted environment of Porto Marghera. On the other hand, CH clams appeared to respond more effectively to copper

  19. Can ecological history influence response to pollutants? Transcriptomic analysis of Manila clam collected in different Venice lagoon areas and exposed to heavy metal.

    PubMed

    Milan, Massimo; Matozzo, Valerio; Pauletto, Marianna; Di Camillo, Barbara; Giacomazzo, Matteo; Boffo, Luciano; Binato, Giovanni; Marin, Maria Gabriella; Patarnello, Tomaso; Bargelloni, Luca

    2016-05-01

    Chronic exposure to environmental pollutants can exert strong selective pressures on natural populations, favoring the transmission over generations of traits that enable individuals to survive and thrive in highly impacted environments. The lagoon of Venice is an ecosystem subject to heavy anthropogenic impact, mainly due to the industrial activities of Porto Marghera (PM), which led to a severe chemical contamination of soil, groundwater, and sediments. Gene expression analysis on wild Manila clams collected in different Venice lagoon areas enabled to identify differences in gene expression profiles between clams collected in PM and those sampled in clean areas, and the definition of molecular signatures of chemical stress. However, it remains largely unexplored to which extent modifications of gene expression patterns persists after removing the source of contamination. It is also relatively unknown whether chronic exposure to xenobiotics affects the response to other chemical pollutants. To start exploring such issues, in the present study a common-garden experiment was coupled with transcriptomic analysis, to compare gene expression profiles of PM clams with those of clams collected in the less impacted area of Chioggia (CH) during a period under the same control conditions. Part of the two experimental groups were also exposed to copper for seven days to assess whether different "ecological history" does influence response to such pollutant. The results obtained suggest that the chronic exposure to chemical pollution generated a response at the transcriptional level that persists after removal for the contaminated site. These transcriptional changes are centered on key biological processes, such as defense against either oxidative stress or tissue/protein damage, and detoxification, suggesting an adaptive strategy for surviving in the deeply impacted environment of Porto Marghera. On the other hand, CH clams appeared to respond more effectively to copper

  20. Geological Investigation and analysis in response to Earthquake Induced Landslide in West Sumatra

    NASA Astrophysics Data System (ADS)

    Karnawati, D.; Wilopo, W.; Salahudin, S.; Sudarno, I.; Burton, P.

    2009-12-01

    Substantial socio-economical loss occurred in response to the September 30. 2009 West Sumatra Earthquake with magnitude of 7.6. Damage of houses and engineered structures mostly occurred at the low land of alluvium sediments due to the ground amplification, whilst at the high land of mountain slopes several villages were buried by massive debris of rocks and soils. It was recorded that 1115 people died due to this disasters. Series of geological investigation was carried out by Geological Engineering Department of Gadjah Mada University, with the purpose to support the rehabilitation program. Based on this preliminary investigation it was identified that most of the house and engineered structural damages at the alluvial deposits mainly due to by the poor quality of such houses and engineered structures, which poorly resist the ground amplification, instead of due to the control of geological conditions. On the other hand, the existence and distribution of structural geology (faults and joints) at the mountaineous regions are significant in controlling the distribution of landslides, with the types of rock falls, debris flows and debris falls. Despite the landslide susceptibility mapping conducted by Geological Survey of Indonesia, more detailed investigation is required to be carried out in the region surrounding Maninjau Lake, in order to provide safer places for village relocation. Accordingly Gadjah Mada University in collaboration with the local university (Andalas University) as well as with the local Government of Agam Regency and the Geological Survey of Indonesia, serve the mission for conducting rather more detailed geological and landslide investigation. It is also crucial that the investigation (survey and mapping) on the social perception and expectation of local people living in this landslide susceptible area should also be carried out, to support the mitigation effort of any future potential earthquake induced landslides.

  1. Activity Book: Ocean Ecology.

    ERIC Educational Resources Information Center

    Learning, 1992

    1992-01-01

    Presents a collection of activities to help elementary students study ocean ecology. The activities have students investigate ocean inhabitants, analyze animal adaptations, examine how temperature and saltiness affect ocean creatures, and learn about safeguarding the sea. Student pages offer reproducible learning sheets. (SM)

  2. Ecology and Human Values.

    ERIC Educational Resources Information Center

    1970

    "Ecology and Human Values" is an interdisciplinary course designed for senior year high school students in social studies and/or science. Its main thrust is the investigation of human values as they relate to the environment, although rooted in the natural sciences as a means of understanding the complexities inherent in the environment. Use is…

  3. Microbial ecological response of the intestinal flora of Peromyscus maniculatus and P. leucopus to heavy metal contamination.

    PubMed

    Coolon, Joseph D; Jones, Kenneth L; Narayanan, Sanjeev; Wisely, Samantha M

    2010-03-01

    Heavy metal contamination negatively affects natural systems including plants, birds, fish and bacteria by reducing biodiversity at contaminated sites. At the Tri-State Mining District, efforts have been made to remediate sites to mitigate the detrimental effects that contamination has caused on human health. While the remediation effort has returned the site to within federal safety standards, it is unclear if this effort is sufficient to restore floral and faunal communities. Intrinsic to ecosystem and organism health is the biodiversity and composition of microbial communities. We have taken advantage of recent advances in sequencing technology and surveyed the bacterial community of remediated and reference soils as well as the intestinal microbial community of two ubiquitous rodent species to provide insight on the impacts of residual heavy metal contamination on the ecosystem. Rodents found on the remediated site had reduced body mass, smaller body size and lower body fat than animals on reference sites. Using bar-coded, massively parallel sequencing, we found that bacterial communities in both the soil and Peromyscus spp. gastrointestinal tracts had no difference in diversity between reference and remediated sites but assemblages differed in response to contamination. These results suggest that niche voids left by microbial taxa that were unable to deal with the remnant levels of heavy metals on remediated sites were replaced by taxa that could persist in this environment. Whether this replacement provided similar ecosystem services as ancestral bacterial communities is unknown. PMID:20331771

  4. Microbial ecological response of the intestinal flora of Peromyscus maniculatus and P. leucopus to heavy metal contamination.

    PubMed

    Coolon, Joseph D; Jones, Kenneth L; Narayanan, Sanjeev; Wisely, Samantha M

    2010-03-01

    Heavy metal contamination negatively affects natural systems including plants, birds, fish and bacteria by reducing biodiversity at contaminated sites. At the Tri-State Mining District, efforts have been made to remediate sites to mitigate the detrimental effects that contamination has caused on human health. While the remediation effort has returned the site to within federal safety standards, it is unclear if this effort is sufficient to restore floral and faunal communities. Intrinsic to ecosystem and organism health is the biodiversity and composition of microbial communities. We have taken advantage of recent advances in sequencing technology and surveyed the bacterial community of remediated and reference soils as well as the intestinal microbial community of two ubiquitous rodent species to provide insight on the impacts of residual heavy metal contamination on the ecosystem. Rodents found on the remediated site had reduced body mass, smaller body size and lower body fat than animals on reference sites. Using bar-coded, massively parallel sequencing, we found that bacterial communities in both the soil and Peromyscus spp. gastrointestinal tracts had no difference in diversity between reference and remediated sites but assemblages differed in response to contamination. These results suggest that niche voids left by microbial taxa that were unable to deal with the remnant levels of heavy metals on remediated sites were replaced by taxa that could persist in this environment. Whether this replacement provided similar ecosystem services as ancestral bacterial communities is unknown.

  5. The VEMAP integrated dataset for simulation of ecological responses to global change: Current climate and climate change scenarios

    SciTech Connect

    Kittel, T.G.F. |

    1995-06-01

    The Vegetation/Ecosystem Modeling and Analysis Project (VEMAP) dataset consists of inputs for biogeochemical and biogeographical models, including current climate, climate scenarios, soils, and vegetation for the conterminous United States on a 0.5 deg lat./lon. grid. The set has daily and monthly representations of climate. Monthly temperature (T) and precipitation (PPT) were derived from station records or statistically-generated from nearby stations. These values were interpolated to the grid accounting for orographic effects in an effort to make the grid-scale climate representative of actual bioclimates within grid cells; this was crucial because ecosystem responses are nonlinearly related to climate. Daily T and PPT were stochastically simulated with WGEN, and daily solar radiation and humidity empirically estimated with CLIMSIM. Equilibrium climate change scenarios were selected to capture a range of potential change from GCM experiments. Transient scenario rates of change were based on atmosphere-ocean GCM results. Mean climate, equilibrium scenarios, vegetation, and soil data are available on CD-ROM.

  6. Phytoplankton shifts in response to rapid eutrophication: palaeo-ecological evidence from a polluted coastal embayment in China

    NASA Astrophysics Data System (ADS)

    Liu, Dongyan

    2013-04-01

    A multi-proxy palaeoecological method has been used to reconstruct a 100-year time series showing coastal eutrophic processes and phytoplankton response. Total organic carbon, total nitrogen, diatom frustules, dinoflagellate cysts, brassicasterol and dinosterol were extracted from chronologic sediment cores in Sishili Bay, a polluted Chinese coastal bay. The variations of these parameters in the cores showed that eutrophic processes occurred during about 1975-1985, which corresponds to increased human activity associated with China's economic development since 1978. During the processes of eutrophication, the biomass of diatoms and dinoflagellates increased and dominant species shifted abruptly. Small heavily silicified diatoms Cyclotella stylorum and Paralia sulcata gradually took the place of the large dominant diatom Coscinodiscus radiatus, while dinoflagellates displayed a progressive increase since 1975. Compared with the changes in temperature and rainfall during 1950-2010, increased fertilizer use, marine aquaculture and sewage discharge displayed a better match to the timeline of increased trend in biomass, species shift and nutrient concentration. Altered nutrient supply ratios caused by significant increased nitrogen could play an important role on the shifts in diatom and dinoflagellate assemblages.

  7. Investigation of the Leak Response of a Carbon-Fiber Laminate Loaded in Biaxial Tension

    NASA Technical Reports Server (NTRS)

    Jackson, Wade C.; Ratcliffe, James G.

    2013-01-01

    Designers of pressurized structures have been reluctant to use composite materials because of concerns over leakage. Biaxial stress states are expected to be the worst-case loading condition for allowing leakage to occur through microcracks. To investigate the leakage behavior under in-plane biaxial loading, a cruciform composite specimen was designed that would have a relatively large test section with a uniform 1:1 biaxial loading ratio. A 7.6-cm-square test section was desired for future investigations of the leakage response as a result of impact damage. Many iterations of the cruciform specimen were evaluated using finite element analysis to reduce stress concentrations and maximize the size of the uniform biaxial strain field. The final design allowed the specimen to go to relatively high biaxial strain levels without incurring damage away from the test section. The specimen was designed and manufactured using carbon/epoxy fabric with a four-ply-thick, quasi-isotropic, central test section. Initial validation and testing were performed on a specimen without impact damage. The specimen was tested to maximum biaxial strains of approximately 4500micro epsilon without apparent damage. A leak measurement system containing a pressurized cavity was clamped to the test section and used to measure the flow rate through the specimen. The leakage behavior of the specimen was investigated for pressure differences up to 172 kPa

  8. Numerical and experimental investigation of the bending response of thin-walled composite cylinders

    NASA Technical Reports Server (NTRS)

    Fuchs, J. P.; Hyer, M. W.; Starnes, J. H., Jr.

    1993-01-01

    A numerical and experimental investigation of the bending behavior of six eight-ply graphite-epoxy circular cylinders is presented. Bending is induced by applying a known end-rotation to each end of the cylinders, analogous to a beam in bending. The cylinders have a nominal radius of 6 inches, a length-to-radius ratio of 2 and 5, and a radius-to-thickness ratio of approximately 160. A (+/- 45/0/90)S quasi-isotropic layup and two orthotropic layups, (+/- 45/0 sub 2)S and (+/- 45/90 sub 2)S, are studied. A geometrically nonlinear special-purpose analysis, based on Donnell's nonlinear shell equations, is developed to study the prebuckling responses and gain insight into the effects of non-ideal boundary conditions and initial geometric imperfections. A geometrically nonlinear finite element analysis is utilized to compare with the prebuckling solutions of the special-purpose analysis and to study the buckling and post buckling responses of both geometrically perfect and imperfect cylinders. The imperfect cylinder geometries are represented by an analytical approximation of the measured shape imperfections. Extensive experimental data are obtained from quasi-static tests of the cylinders using a test fixture specifically designed for the present investigation. A description of the test fixture is included. The experimental data are compared to predictions for both perfect and imperfect cylinder geometries. Prebuckling results are presented in the form of displacement and strain profiles. Buckling end-rotations, moments, and strains are reported, and predicted mode shapes are presented. Observed and predicted moment vs. end-rotation relations, deflection patterns, and strain profiles are illustrated for the post buckling responses. It is found that a geometrically nonlinear boundary layer behavior characterizes the prebuckling responses. The boundary layer behavior is sensitive to laminate orthotropy, cylinder geometry, initial geometric imperfections, applied end

  9. Heading in football. Part 1: Development of biomechanical methods to investigate head response

    PubMed Central

    Shewchenko, N; Withnall, C; Keown, M; Gittens, R; Dvorak, J

    2005-01-01

    Objectives: There has been growing controversy regarding long term effects of repeated low severity head impacts such as when heading a football. However, there are few scientific data substantiating these concerns in terms of the biomechanical head response to impact. The present study aimed to develop a research methodology to investigate the biomechanical response of human subjects during intentional heading and identify strategies for reducing head impact severity. Methods: A controlled laboratory study was carried out with seven active football players, aged 20–23 and of average stature and weight. The subjects were fitted with photographic targets for kinematic analysis and instrumented to measure head linear/angular accelerations and neck muscle activity. Balls were delivered at two speeds (6 m/s and 8 m/s) as the subjects executed several specific forward heading manoeuvres in the standing position. Heading speeds up to 11 m/s were seen when the head closing speed was considered. One subject demonstrating averaged flexion–extension muscle activity phased with head acceleration data and upper torso kinematics was used to validate a biofidelic 50th percentile human model with a detailed head and neck. The model was exercised under ball incoming speeds of 6–7 m/s with parameter variations including torso/head alignment, neck muscle tensing, and follow through. The model output was subsequently compared with additional laboratory tests with football players (n = 3). Additional heading scenarios were investigated including follow through, non-active ball impact, and non-contact events. Subject and model head responses were evaluated with peak linear and rotational accelerations and maximum incremental head impact power. Results: Modelling of neck muscle tensing predicted lower head accelerations and higher neck loads whereas volunteer head acceleration reductions were not consistent. Modelling of head–torso alignment predicted a modest reduction in

  10. Investigating genotype specific response in photosynthetic behavior under drought stress and nitrogen limitation in Brassica rapa.

    NASA Astrophysics Data System (ADS)

    Pleban, J. R.; Mackay, D. S.; Ewers, B. E.; Weinig, C.; Aston, T.

    2015-12-01

    Challenges in terrestrial ecosystem modeling include characterizing the impact of stress on vegetation and the heterogeneous behavior of different species within the environment. In an effort to address these challenges the impacts of drought and nutrient limitation on the CO2 assimilation of multiple genotypes of Brassica rapa was investigated using the Farquhar Model (FM) of photosynthesis following a Bayesian parameterization and updating scheme. Leaf gas exchange and chlorophyll fluorescence measurements from an unstressed group (well-watered/well-fertilized) and two stressed groups (drought/well-fertilized and well-watered/nutrient limited) were used to estimate FM model parameters. Unstressed individuals were used to initialize Bayesian parameter estimation. Posterior mean estimates yielded a close fit with data as observed assimilation (An) closely matched predicted (Ap) with mean standard error for all individuals ranging from 0.8 to 3.1 μmol CO2 m-2 s-1. Posterior parameter distributions of the unstressed individuals were combined and fit to distributions to establish species level Bayesian priors of FM parameters for testing stress responses. Species level distributions of unstressed group identified mean maximum rates of carboxylation standardized to 25° (Vcmax25) as 101.8 μmol m-2 s-1 (± 29.0) and mean maximum rates of electron transport standardized to 25° (Jmax25) as 319.7 μmol m-2 s-1 (± 64.4). These updated priors were used to test the response of drought and nutrient limitations on assimilation. In the well-watered/nutrient limited group a decrease of 28.0 μmol m-2 s-1 was observed in mean estimate of Vcmax25, a decrease of 27.9 μmol m-2 s-1 in Jmax25 and a decrease in quantum yield from 0.40 mol photon/mol e- in unstressed individuals to 0.14 in the nutrient limited group. In the drought/well-fertilized group a decrease was also observed in Vcmax25 and Jmax25. The genotype specific unstressed and stressed responses were then used to

  11. Trash Ecology

    ERIC Educational Resources Information Center

    Lind, Georgia J.

    2004-01-01

    A hands on activity involving density, frequency and biomass using transects, quadrats and a local good deed by cleaning up the neighborhood while practicing important techniques in ecology is detailed. The activity is designed for KCC-STEP, whose primary goal is to expand the scientific knowledge and research experiences of their students, who…

  12. Defending Ecology.

    ERIC Educational Resources Information Center

    Margolis, Brian

    2000-01-01

    Explains how non-native species' problems in the ecosystem can introduce fundamental ecological principles in the classroom. Provides background information on damages caused by non-native species. Discusses how educators can use this environmental issue in the classroom and gives the example of zebra mussels. Lists instructional strategies for…

  13. Ecological responses of a large shallow lake (Okeechobee, Florida) to climate change and potential future hydrologic regimes.

    PubMed

    Havens, Karl E; Steinman, Alan D

    2015-04-01

    We considered how Lake Okeechobee, a large shallow lake in Florida, USA, might respond to altered hydrology associated with climate change scenarios in 2060. Water budgets and stage hydrographs were provided from the South Florida Water Management Model, a regional hydrologic model used to develop plans for Everglades restoration. Future scenarios include a 10% increase or decrease in rainfall (RF) and a calculated increase in evapotranspiration (ET), which is based on a 1.5 °C rise in temperature. Increasing RF and ET had counter-balancing effects on the water budget and when changing concurrently did not affect hydrology. In contrast, when RF decreased while ET increased, this resulted in a large change in hydrology. The surface elevation of the lake dropped by more than 2 m under this scenario compared to a future base condition, and extreme low elevation persisted for multiple years. In this declining RF/increasing ET scenario, the littoral and near-shore zones, areas that support emergent and submerged plants, were dry 55% of the time compared to less than 4% of the time in the future base run. There also were times when elevation increased as much as 3 m after intense RF events. Overall, these changes in hydrologic conditions would dramatically alter ecosystem services. Uncertainty about responses is highest at the pelagic-littoral interface, in regard to whether an extremely shallow lake could support submerged vascular plants, which are critical to the recreational fishery and for migratory birds. Along with improved regional climate modeling, research in that interface zone is needed to guide the adaptive process of Everglades restoration.

  14. Automated experimentation in ecological networks

    PubMed Central

    2011-01-01

    Background In ecological networks, natural communities are studied from a complex systems perspective by representing interactions among species within them in the form of a graph, which is in turn analysed using mathematical tools. Topological features encountered in complex networks have been proved to provide the systems they represent with interesting attributes such as robustness and stability, which in ecological systems translates into the ability of communities to resist perturbations of different kinds. A focus of research in community ecology is on understanding the mechanisms by which these complex networks of interactions among species in a community arise. We employ an agent-based approach to model ecological processes operating at the species' interaction level for the study of the emergence of organisation in ecological networks. Results We have designed protocols of interaction among agents in a multi-agent system based on ecological processes occurring at the interaction level between species in plant-animal mutualistic communities. Interaction models for agents coordination thus engineered facilitate the emergence of network features such as those found in ecological networks of interacting species, in our artificial societies of agents. Conclusions Agent based models developed in this way facilitate the automation of the design an execution of simulation experiments that allow for the exploration of diverse behavioural mechanisms believed to be responsible for community organisation in ecological communities. This automated way of conducting experiments empowers the study of ecological networks by exploiting the expressive power of interaction models specification in agent systems. PMID:21554669

  15. The historical ecology of Namibian rangelands: vegetation change since 1876 in response to local and global drivers.

    PubMed

    Rohde, Richard F; Hoffman, M Timm

    2012-02-01

    The influence of both local and global drivers on long-term changes in the vegetation of Namibia's extensive rangelands was investigated. Fifty-two historical photographs of the Palgrave Expedition of 1876 were re-photographed and used to document changes over more than 130 years, in grass, shrub and tree cover within three major biomes along a 1200km climatic gradient in central and southern Namibia. We showed that patterns of change are correlated with mean annual precipitation (MAP) and that below a threshold of around 250mm, vegetation has remained remarkably stable regardless of land-use or tenure regime. Above this threshold, an increase in tree cover is linked to the rainfall gradient, the legacies of historical events in the late 19th century, subsequent transformations in land-use and increased atmospheric CO(2). We discuss these findings in relation to pastoral and settler societies, paleo- and historical climatic trends and predictions of vegetation change under future global warming scenarios. We argue that changes in land-use associated with colonialism (decimation of megaherbivores and wildlife browsers; fire suppression, cattle ranching), as well as the effects of CO(2) fertilisation provide the most parsimonious explanations for vegetation change. We found no evidence that aridification, as projected under future climate change scenarios, has started in the region. This study provided empirical evidence and theoretical insights into the relative importance of local and global drivers of change in the savanna environments of central and southern Namibia and global savanna ecosystems more generally.

  16. The response of skin to applied stress: investigation of bitemark distortion in a cadaver model.

    PubMed

    Bush, Mary A; Thorsrud, Kyle; Miller, Raymond G; Dorion, Robert B J; Bush, Peter J

    2010-01-01

    Knowledge of distortional properties of skin is important in bitemark analysis. Thus, the response of skin to stress from bites was investigated. Four sets of models were created from the dentition of one individual. Anterior teeth were systematically removed to vary contact surface area. A biting apparatus was constructed with an integrated load cell. Forty-six bites were created perpendicular to Langer lines on six cadavers. Rate of force application and bite pressure were controlled. Metric/angular measurement and hollow volume overlays were employed. Distortion produced by each dentition was calculated and assessed. Results showed that as teeth impressed loose tissue, mesial/distal distance increased, angles of rotation flattened, and inter-canine distance lengthened. An opposite effect was seen in tight tissue. When the surface area of the dentition was reduced, a mixture of these effects was observed. Conclusions indicated that stiffness of the tissue was the most important variable in bitemark distortion. PMID:20002269

  17. An investigation of body part as object (BPO) responses in normal and brain-damaged adults.

    PubMed

    Duffy, R J; Duffy, J R

    1989-07-01

    A test of simple pantomime was administered to three groups of adults and comparisons were made across groups of the incidence of subjects who exhibited body part as object (BPO) responses and of the mean frequency of occurrence of BPO in each group. The three groups were left-hemisphere-damaged aphasics (N = 28), right-hemisphere-damaged (N = 24), and normal controls (N = 28). The results indicated no significant differences among groups on the BPO measures. Also, to test the strength of association between the frequency of occurrence of BPO and measures of limb apraxia and severity of aphasia for the left-hemisphere-damaged aphasic group, correlation coefficients were obtained. The correlations were low and nonsignificant. The results of this investigation do not support the common clinical assumption that the occurrence of BPO during the performance of simple pantomimes is pathognomic for left-hemisphere pathology or associated with limb apraxia.

  18. The Coffee Berry Borer (Hypothenemus hampei) Invades Hawaii: Preliminary Investigations on Trap Response and Alternate Hosts

    PubMed Central

    Messing, Russell H.

    2012-01-01

    In August 2010 the coffee berry borer, Hypothenemus hampei, was first reported to have invaded the Kona coffee growing region of Hawaii, posing a severe economic challenge to the fourth largest agricultural commodity in the State. Despite its long and widespread occurrence throughout the tropics as the most serious pest of coffee, there are still discrepancies in the literature regarding several basic aspects of berry borer biology relevant to its control. In Kona coffee plantations, we investigated the beetles’ response to several trap and lure formulations, and examined the occurrence of beetles in seeds of alternate host plants occurring adjacent to coffee farms. While traps were shown to capture significant numbers of beetles per day, and the occurrence of beetles in alternate hosts was quite rare, the unique situation of coffee culture in Hawaii will make this pest extremely challenging to manage in the Islands. PMID:26466620

  19. Linear response of light deformed nuclei investigated by self-consistent quasiparticle random-phase approximation

    SciTech Connect

    Losa, C.; Doessing, T.; Pastore, A.; Vigezzi, E.; Broglia, R. A.

    2010-06-15

    We present a calculation of the properties of vibrational states in deformed, axially-symmetric even-even nuclei, within the framework of a fully self-consistent quasiparticle random phase approximation (QRPA). The same Skyrme energy density and density-dependent pairing functionals are used to calculate the mean field and the residual interaction in the particle-hole and particle-particle channels. We have tested our software in the case of spherical nuclei against fully self-consistent calculations published in the literature, finding excellent agreement. We investigate the consequences of neglecting the spin-orbit and Coulomb residual interactions in QRPA. Furthermore we discuss the improvement obtained in the QRPA result associated with the removal of spurious modes. Isoscalar and isovector responses in the deformed {sup 24-26}Mg, {sup 34}Mg isotopes are presented and compared to experimental findings.

  20. Investigation of the Thermomechanical Response of Shape Memory Alloy Hybrid Composite Beams

    NASA Technical Reports Server (NTRS)

    Davis, Brian A.

    2005-01-01

    Previous work at NASA Langley Research Center (LaRC) involved fabrication and testing of composite beams with embedded, pre-strained shape memory alloy (SMA) ribbons. That study also provided comparison of experimental results with numerical predictions from a research code making use of a new thermoelastic model for shape memory alloy hybrid composite (SMAHC) structures. The previous work showed qualitative validation of the numerical model. However, deficiencies in the experimental-numerical correlation were noted and hypotheses for the discrepancies were given for further investigation. The goal of this work is to refine the experimental measurement and numerical modeling approaches in order to better understand the discrepancies, improve the correlation between prediction and measurement, and provide rigorous quantitative validation of the numerical model. Thermal buckling, post-buckling, and random responses to thermal and inertial (base acceleration) loads are studied. Excellent agreement is achieved between the predicted and measured results, thereby quantitatively validating the numerical tool.

  1. Investigating membrane and mitochondrial cryobiological responses of HUVEC using interrupted cooling protocols.

    PubMed

    Reardon, Anthony J F; Elliott, Janet A W; McGann, Locksley E

    2015-10-01

    The success of cryopreservation protocols is largely based on membrane integrity assessments after thawing, since membrane integrity can be considered to give an upper limit in assessment of cell viability and the plasma membrane is considered to be a primary site of cryoinjury. However, the exposure of cells to conditions associated with low temperatures can induce injury to cellular structure and function that may not be readily identified by membrane integrity alone. Interrupted cooling protocols (including interrupted slow cooling without a hold time (graded freezing), and interrupted rapid cooling with a hold time (two-step freezing)), can yield important information about cryoinjury by separating the damage that occurs upon cooling to (and possibly holding at) a critical intermediate temperature range from the damage that occurs upon plunging to the storage temperature (liquid nitrogen). In this study, we used interrupted cooling protocols in the absence of cryoprotectant to investigate the progression of damage to human umbilical vein endothelial cells (HUVEC), comparing an assessment of membrane integrity with a mitochondrial polarization assay. Additionally, the membrane integrity response of HUVEC to interrupted cooling was investigated as a function of cooling rate (for interrupted slow cooling) and hold time (for interrupted rapid cooling). A key finding of this work was that under slow cooling conditions which resulted in a large number of membrane intact cells immediately post thaw, mitochondria are predominantly in a non-functional depolarized state. This study, the first to look directly at mitochondrial polarization throughout interrupted cooling profiles and a detailed study of HUVEC response, highlights the complexity of the progression of cell damage, as the pattern and extent of cell injury throughout the preservation process differs by injury site. PMID:26254036

  2. Proteomic-based mechanistic investigation of low-dose radiation-induced cellular responses/effects

    SciTech Connect

    Chen, Xian

    2013-10-23

    The goal of our project is to apply our unique systems investigation strategy to reveal the molecular mechanisms underlying the radiation induction and transmission of oxidative damage, adaptive response, and bystander effect at low-doses. Beginning with simple in vitro systems such as fibroblast or epithelial pure culture, our amino acid-coded mass tagging (AACT) comparative proteomic platform will be used to measure quantitatively proteomic changes at high- or low-dose level with respect to their endogenous damage levels respectively, in which a broad range of unique regulated proteins sensitive to low-dose IR will be distinguished. To zoom in how these regulated proteins interact with other in the form of networks in induction/transmission pathways, these regulated proteins will be selected as baits for making a series of fibroblast cell lines that stably express each of them. Using our newly developed method of ?dual-tagging? quantitative proteomics that integrate the capabilities of natural complex expression/formation, simple epitope affinity isolation (not through tandem affinity purification or TAP), and ?in-spectra? AACT quantitative measurements using mass spectrometry (MS), we will be able to distinguish systematically interacting proteins with each bait in real time. Further, in addition to both proteome-wide (global differentially expressed proteins) and pathway-scale (bait-specific) profiling information, we will perform a computational network analysis to elucidate a global pathway/mechanisms underlying cellular responses to real-time low-dose IR. Similarly, we will extend our scheme to investigate systematically those induction/transmission pathways occurring in a fibroblast-epithelial interacting model in which the bystander cell (fibroblast) monitor the IR damage to the target cell (epithelial cell). The results will provide the proteome base (molecular mechanisms/pathways for signaling) for the low dose radiation-induced essential tissue

  3. A numerical investigation of vapor intrusion--the dynamic response of contaminant vapors to rainfall events.

    PubMed

    Shen, Rui; Pennell, Kelly G; Suuberg, Eric M

    2012-10-15

    The U.S. government and various agencies have published guidelines for field investigation of vapor intrusion, most of which suggest soil gas sampling as an integral part of the investigation. Contaminant soil gas data are often relatively more stable than indoor air vapor concentration measurements, but meteorological conditions might influence soil gas values. Although a few field and numerical studies have considered some temporal effects on soil gas vapor transport, a full explanation of the contaminant vapor concentration response to rainfall events is not available. This manuscript seeks to demonstrate the effects on soil vapor transport during and after different rainfall events, by applying a coupled numerical model of fluid flow and vapor transport. Both a single rainfall event and seasonal rainfall events were modeled. For the single rainfall event models, the vapor response process could be divided into three steps: namely, infiltration, water redistribution, and establishment of a water lens atop the groundwater source. In the infiltration step, rainfall intensity was found to determine the speed of the wetting front and wash-out effect on the vapor. The passage of the wetting front led to an increase of the vapor concentration in both the infiltration and water redistribution steps and this effect is noted at soil probes located 1m below the ground surface. When the mixing of groundwater with infiltrated water was not allowed, a clean water lens accumulated above the groundwater source and led to a capping effect which can reduce diffusion rates of contaminant from the source. Seasonal rainfall with short time intervals involved superposition of the individual rainfall events. This modeling results indicated that for relatively deeper soil that the infiltration wetting front could not flood, the effects were damped out in less than a month after rain; while in the long term (years), possible formation of a water lens played a larger role in determining

  4. A detailed investigation of the strain hardening response of aluminum alloyed Hadfield steel

    NASA Astrophysics Data System (ADS)

    Canadinc, Demircan

    The unusual strain hardening response exhibited by Hadfield steel single and polycrystals under tensile loading was investigated. Hadfield steel, which deforms plastically through the competing mechanisms slip and twinning, was alloyed with aluminum in order to suppress twinning and study the role of slip only. To avoid complications due to a grained structure, only single crystals of the aluminum alloyed Hadfield steel were considered at the initial stage of the current study. As a result of alloying with aluminum, twinning was suppressed; however a significant increase in the strain hardening response was also present. A detailed microstructural analysis showed the presence of high-density dislocation walls that evolve in volume fraction due to plastic deformation and interaction with slip systems. The very high strain hardening rates exhibited by the aluminum alloyed Hadfield steel single crystals was attributed to the blockage of glide dislocations by the high-density dislocation walls. A crystal plasticity model was proposed, that accounts for the volume fraction evolution and rotation of the dense dislocation walls, as well as their interaction with the active slip systems. The novelty of the model lies in the simplicity of the constitutive equations that define the strain hardening, and the fact that it is based on experimental data regarding the microstructure. The success of the model was tested by its application to different crystallographic orientations, and finally the polycrystals of the aluminum alloyed Hadfield steel. Meanwhile, the capability of the model to predict texture was also observed through the rotation of the loading axis in single crystals. The ability of the model to capture the polycrystalline deformation response provides a venue for its utilization in other alloys that exhibit dislocation sheet structures.

  5. Investigation on the frequency response characteristics of an instrument for laser vibrometry and laser displacementmetry

    NASA Astrophysics Data System (ADS)

    Umeda, Akira; Ueda, Kazunaga

    1996-09-01

    This paper proposes the new technique for the frequency response characterization of the laser vibrometry or the laser displacementmetry, where the optical interference is the working principle. In order to investigate the frequency response of laser vibrometers or laser displacement meters, the surface of high speed translational motion with the broad frequency bandwidth is absolutely required. That motion is materialized by the reflection of an elastic pulse propagating in a metal bar. A projectile made of aluminum is accelerated by the pressurized air and impinges on one end surface of the bar. The elastic wave is generated by the collision and propagates in the bar axis direction and reflects at the other end surface of the bar. The bar is supported by four steel bearing balls which are placed on the V-shaped grooves. The motion of the end surface can be considered to be in plain based on the numerical calculation. The surface is measured simultaneously using the reference laser interferometer developed in NRLM and a laser displacement meter based on the heterodyne technique (Hoshin Electronics HS-1100). HS-1100 uses the real time fringe counting technique. The reference interferometer, on the other hand uses a transient recorder (Tektronix RTD-710) which stores all of the interference signals during the elastic pulse reflection. The analysis and the wave form calculation based on the phase analysis is done after the experiment, leading to the broad frequency bandwidth. The comparison in the frequency domain using Fast Fourier Transform provides the frequency response characteristics of the tested laser displacement meter. It turned out that bandwidth of HS-1100 was up to 20 kHz, though the design value was 100 kHz.

  6. A theoretical investigation on influences of slab tracks on vertical dynamic responses of railway viaducts

    NASA Astrophysics Data System (ADS)

    Shi, Li; Cai, Yuanqiang; Wang, Peng; Sun, Honglei

    2016-07-01

    A railway viaduct model consisting of infinite spans of elastically-supported girders carrying a slab track of infinite length is established to investigate the influence of the slabs on the vertical dynamic response of the viaduct, when a moving harmonic point load or a moving sprung wheel is applied. The infinite rail, the discontinuous slabs and girders of identical span lengths are idealized as Euler-Bernoulli beams. The rail fasteners, the cushion layer beneath the slab and the elastic bearings at the girder supports are represented by discretely distributed springs of hysteretic damping. Due to the repetitive nature of the girders, the model can be divided into periodic three-beam units by the span length of the girder, and then solved analytically in the frequency domain using the property of periodic structure. Besides the first natural frequency of the girder with elastic bearings, it is found that the resonance frequency of the slab on the cushion layer has a significant influence on the dynamic response of the track and the girder. Parametric excitations due to the moving wheel periodically passing the discontinuous slabs contribute significantly to the wheel/rail interactions.

  7. The brain’s response to pleasant touch: an EEG investigation of tactile caressing

    PubMed Central

    Singh, Harsimrat; Bauer, Markus; Chowanski, Wojtek; Sui, Yi; Atkinson, Douglas; Baurley, Sharon; Fry, Martin; Evans, Joe; Bianchi-Berthouze, Nadia

    2014-01-01

    Somatosensation as a proximal sense can have a strong impact on our attitude toward physical objects and other human beings. However, relatively little is known about how hedonic valence of touch is processed at the cortical level. Here we investigated the electrophysiological correlates of affective tactile sensation during caressing of the right forearm with pleasant and unpleasant textile fabrics. We show dissociation between more physically driven differential brain responses to the different fabrics in early somatosensory cortex – the well-known mu-suppression (10–20 Hz) – and a beta-band response (25–30 Hz) in presumably higher-order somatosensory areas in the right hemisphere that correlated well with the subjective valence of tactile caressing. Importantly, when using single trial classification techniques, beta-power significantly distinguished between pleasant and unpleasant stimulation on a single trial basis with high accuracy. Our results therefore suggest a dissociation of the sensory and affective aspects of touch in the somatosensory system and may provide features that may be used for single trial decoding of affective mental states from simple electroencephalographic measurements. PMID:25426047

  8. Investigation of internal microstructure and thermo-responsive properties of composite PNIPAM/silica microcapsules.

    PubMed

    Cejková, Jitka; Hanus, Jaroslav; Stepánek, Frantisek

    2010-06-15

    Composite microcapsules consisting of a thermo-responsive hydrogel poly-N-isopropylacrylamide (PNIPAM) and coated by silica (SiO(2)) nanoparticles have been synthesized by the inverse Pickering emulsion polymerization method. The composite capsules, whose mean diameter is in the 25-86 microm range in the expanded state, were characterized by static light scattering, atomic force microscopy (AFM), scanning electron microscopy (SEM), and laser scanning confocal microscopy (LSCM). It is reported that the hydrogel surface is uniformly covered by a monolayer of silica nanoparticles and that depending on the capsule size and degree of polymer cross-linking, either hollow-core or partially-filled hydrogel-core microcapsules can be created. Equilibrium thermo-responsive behavior of the composite microcapsules is investigated and it is found that after heating the particles above the lower critical solution temperature (LCST) of PNIPAM, the shrinkage ratio V/V(max) varies from 0.8 to 0.4 for a cross-linking ratio from 0.6% to 9% on a mass basis. Dynamic temperature cycling studies reveal no hysteresis in the shrinking and recovery phases, but a small measurable dependence of the asymptotic shrinkage ratio V/V(max) on the rate of temperature change exists. The composite capsules are stable under long-term storage in both dried and hydrated states and easily re-dispersible in water. PMID:20304409

  9. Numerical investigation of the hydroelastic response in cavitating flow around a flexible hydrofoil

    NASA Astrophysics Data System (ADS)

    Wu, Q.; Huang, B.; Wang, G. Y.; Wang, J. D.

    2015-01-01

    The objective of this paper is to investigate the hydroelastic response of cavitating flows around a flexible hydrofoil. The numerical simulations are performed by solving the incompressible and unsteady Reynolds Average Navier-Stokes (URANS) equations via the commercial CFD software ANSYS CFX. The k-ω SST turbulence model with the turbulence viscosity correction and the Kubota cavitation model are introduced to the present simulations. The results showed that the cavitation has significantly affected the foil deformation and the evolution of the transient cavity shape and the corresponding hydrodynamic response with time can be divided into three stages: during the development of the attached cavity, the cavity formed on the suction side of the flexible hydrofoil is much larger with a steeper slope of the cavity area, which is caused by the increase of the effective angle of attack due to the twist deformation. During the vortex-cavitation interaction process, the hydrodynamic loads for the rigid hydrofoil remain relatively flat, while that for the flexible hydrofoil fluctuates with high frequency because of the foil deformation, leading to a more complex cavitation pattern due to the interaction with the foil vibration. During the cavity shedding process, both the primary and the residual cavities shed downstream totally, together with the counter-rotational vortex structures, corresponding to a sharp drop in the hydrodynamic loads. The larger effective angle of attack leads to the advanced cavity inception of the next cavitation period.

  10. Motor response investigation in individuals with cerebral palsy using near infrared spectroscopy: pilot study.

    PubMed

    Chaudhary, Ujwal; Hall, Michael; Gonzalez, Jean; Elbaum, Leonard; Bloyer, Martha; Godavarty, Anuradha

    2014-01-20

    Cerebral palsy (CP) describes a group of motor impairment syndromes secondary to genetic that may be due to acquired disorders of the developing brain. In this study, near infrared spectroscopy (NIRS) is used to investigate the prefrontal cortical activation and lateralization in response to the planning and execution of motor skills in controls and individuals with CP. The prefrontal cortex, which plays a dominant role in the planning and execution of motor skill stimulus, is noninvasively imaged using a continuous wave-based NIRS system. During the study, 7 controls (4 right-handed and 3 left-handed) and 2 individuals with CP (1 right-handed and 1 left-handed) over 18 years of age performed 30 s of a ball throwing task followed by 30 s rest in a 5-block paradigm. The optical signal acquired from the NIRS system was processed to elucidate the activation and lateralization in the prefrontal region of controls and individuals with CP. The preliminary result indicated a difference in activation between the task and rest conditions in all the participant types. Bilateral dominance was observed in the prefrontal cortex of controls in response to planning and execution of motor skill tasks, while an ipsilateral dominance was observed in individuals with CP. In conjunction, similar contralateral dominance was observed during rest periods, both in controls and individuals with CP.

  11. Experimental Investigation and Optimization of Response Variables in WEDM of Inconel - 718

    NASA Astrophysics Data System (ADS)

    Karidkar, S. S.; Dabade, U. A.

    2016-02-01

    Effective utilisation of Wire Electrical Discharge Machining (WEDM) technology is challenge for modern manufacturing industries. Day by day new materials with high strengths and capabilities are being developed to fulfil the customers need. Inconel - 718 is similar kind of material which is extensively used in aerospace applications, such as gas turbine, rocket motors, and spacecraft as well as in nuclear reactors and pumps etc. This paper deals with the experimental investigation of optimal machining parameters in WEDM for Surface Roughness, Kerf Width and Dimensional Deviation using DoE such as Taguchi methodology, L9 orthogonal array. By keeping peak current constant at 70 A, the effect of other process parameters on above response variables were analysed. Obtained experimental results were statistically analysed using Minitab-16 software. Analysis of Variance (ANOVA) shows pulse on time as the most influential parameter followed by wire tension whereas spark gap set voltage is observed to be non-influencing parameter. Multi-objective optimization technique, Grey Relational Analysis (GRA), shows optimal machining parameters such as pulse on time 108 Machine unit, spark gap set voltage 50 V and wire tension 12 gm for optimal response variables considered for the experimental analysis.

  12. Piloted Simulator Investigation of Techniques to Achieve Attitude Command Response with Limited Authority Servos

    NASA Technical Reports Server (NTRS)

    Key, David L.; Heffley, Robert K.

    2002-01-01

    The purpose of the study was to develop generic design principles for obtaining attitude command response in moderate to aggressive maneuvers without increasing SCAS series servo authority from the existing +/- 10%. In particular, to develop a scheme that would work on the UH-60 helicopter so that it can be considered for incorporation in future upgrades. The basic math model was a UH-60A version of GENHEL. The simulation facility was the NASA-Ames Vertical Motion Simulator (VMS). Evaluation tasks were Hover, Acceleration-Deceleration, and Sidestep, as defined in ADS-33D-PRF for Degraded Visual Environment (DVE). The DVE was adjusted to provide a Usable Cue Environment (UCE) equal to two. The basic concept investigated was the extent to which the limited attitude command authority achievable by the series servo could be supplemented by a 10%/sec trim servo. The architecture used provided angular rate feedback to only the series servo, shared the attitude feedback between the series and trim servos, and when the series servo approached saturation the attitude feedback was slowly phased out. Results show that modest use of the trim servo does improve pilot ratings, especially in and around hover. This improvement can be achieved with little degradation in response predictability during moderately aggressive maneuvers.

  13. Investigation on the response of fused taper couplers to ultrasonic wave.

    PubMed

    Li, Fengmei; Liu, Yiying; Wang, Linjie; Zhao, Zhenyu

    2015-08-10

    The responses of fused taper couplers with different structure parameters to ultrasonic waves have been investigated theoretically and experimentally. A comprehensive analysis of the acousto-optic interaction was presented, taking into account the elasto-optic geometric effect. It is found that direct deformation of the coupler induced by ultrasonic waves is the critical factor in the sensing mechanism and is closely related to the sensor sensitivity. Moreover, the strain response of the coupler with different structure parameters was analyzed using a 3D coupled acoustic-solid numerical model, which was based on the developed mathematical model. According to the theoretical analyses, related experiments were carried out, and experimental results show that this ultrasonic sensor with a longer stretching length has higher sensitivity and the sensitivity of the sensor takes a nonmonotonic relation with an aspect ratio, which are consistent with the theoretical analyses results. We argue that our work may provide a useful guide in designing and optimizing more sensitive ultrasonic sensors used in practical ultrasonic detection. PMID:26368365

  14. Estimating the Influence of a Tributary on Primary Productivity in Delaware Bay from Continuous Data: Biogeochemical and Ecological Responses to Inputs from the Murderkill

    NASA Astrophysics Data System (ADS)

    Voynova, Y. G.; Lebaron, K. C.; Barnes, R. T.; Ullman, W. J.

    2014-12-01

    Since April 2012, the University of Delaware has operated a real-time water quality monitoring station at Bowers, DE, to determine the effect of nutrient loads from the Murderkill Estuary to the Delaware Bay. The Land Ocean Biogeochemical Observatory (LOBO; Hach/Sea-Bird Electronics) is deployed under a public dock, with support from the Kent County Board of Public Works and Delaware's Department of Natural Resources and Environmental Control, and in collaboration with the USGS that operates a gauging station at the same site (01484085). Every hour the LOBO measures salinity, temperature, pressure, dissolved oxygen, turbidity, chlorophyll, CDOM, nitrate (NO3-) and orthophosphate (PO43-). Ebb tide measurements reflect conditions in the Estuary and flood tide measurements reflect conditions in Delaware Bay. Real-time data are available to the public at kentcounty.loboviz.com. Using hourly data from the LOBO, we are able to assess the nutrient and particle exchange between the Murderkill and the Delaware Bay, as well as biogeochemical and ecological responses to this exchange. Primary production in the turbid Estuary is low and nutrients from the Murderkill are efficiently delivered to Delaware Bay, where O2 production response to nitrate influx is almost instantaneous. In the summer, during the day, nutrients originating in the Estuary (ebb tide NO3- > 50-60 μM) stimulate phytoplankton growth in Delaware Bay, indicated by chlorophyll increases and O2 supersaturation during flood tide. This suggests that the Murderkill and other similar tributaries are important nutrient sources to the Delaware Bay. We use a phase-sensitive analysis to extract data characterizing the Delaware Bay, and then use dissolved oxygen to calculate rates of primary production and respiration. Newly produced Delaware Bay phytoplankton (often > 40 µg Chla L-1) may be an important labile carbon source supporting respiration in the Estuary and its surrounding salt marshes.

  15. Light and desiccation responses of some Hymenophyllaceae (filmy ferns) from Trinidad, Venezuela and New Zealand: poikilohydry in a light-limited but low evaporation ecological niche

    PubMed Central

    Proctor, Michael C. F.

    2012-01-01

    Background and Aims Hymenophyllaceae (filmy ferns) are typically plants of shady, constantly moist habitats. They attain greatest species diversity and biomass in humid tropical montane forests and temperate hyperoceanic climates. This paper presents ecophysiological data bearing on their worldwide ecological niche space and its limits. Methods Chlorophyll fluorescence was used to monitor recovery in desiccation experiments, and for measurements of 95 % saturating irradiance [photosynthetic photon flux density (PPFD95 %)] of photosynthetic electron flow and other parameters, in the New Zealand Hymenophyllum sanguinolentum, and three species each of Hymenophyllum and Trichomanes from forests in Trinidad and Venezuela. Key Results Hymenophyllum sanguinolentum was comparable in desiccation tolerance and light responses with the European species. The more common species in the two tropical forests showed PPFD95 % >100 µmol m−2 s−1, and withstood moderate desiccation (–40 MPa) for several days. The four most shade-adapted species had PPFD95 % ≤51 µmol m−2 s−1, and were sensitive to even mild and brief desiccation (–22 MPa for 3 d). Conclusions Light and desiccation responses of filmy ferns can be seen as an integrated package. At low light and windspeed in humid forests, net radiation and saturation deficit are low, and diffusion resistance high. Water loss is slow and can be supported by modest conduction from the sub-stratum. With higher irradiance, selection pressure for desiccation tolerance increases progressively. With low light and high humidity, the filmy fern pattern of adaptation is probably optimal, and the vascular plant leaf with mesophyll and stomata offers no advantage in light capture, water economy or CO2 uptake. Trade-offs between light adaptation and desiccation tolerance, and between stem conduction and water absorption through the leaf surface, underlie adaptive radiation and niche differentiation of species within the family

  16. Investigating the Response of Greenland Outlet Glaciers to Perturbations Using a 1D Flowline Model

    NASA Astrophysics Data System (ADS)

    Petrakopoulos, K.; Stearns, L. A.; van der Veen, C. J.

    2015-12-01

    Over the past two decades, the behavior of many Greenland tidewater outlet glaciers has been characterized by dramatic acceleration, thinning, and retreat. In some cases this behavior is followed by re-advance, thickening and deceleration. The mechanisms that control glacier stability are not fully understood, and hinder ice sheet mass balance projections. Many studies suggest that accelerations are caused exclusively by processes at the terminus, namely by mechanisms that result in increases in iceberg calving rates. In this study we investigate whether comparable accelerations can initiate at different places along the glacier trunk due to changes in subglacial processes or shear margin evolution. We begin our experiments using a prognostic depth integrated (1-D) flowline model applied to Helheim Glacier, and investigate its flow response to perturbations at the terminus and up-flow. Our work shows that large-scale accelerations could have initiated up-flow far from the terminus. The results of this study will contribute to the long-lasting debate about the role of terminus dynamics, and thus ocean conditions, in modulating ice sheet mass balance.

  17. A theoretical investigation of human skin thermal response to near-infrared laser irradiation

    NASA Astrophysics Data System (ADS)

    Dai, Tianhong; Pikkula, Brian M.; Wang, Lihong V.; Anvari, Bahman

    2004-07-01

    Near-infrared wavelengths are absorbed less by epidermal melanin mainly located at the basal layer of epidermis (dermo-epidermal junction), and penetrate deeper into human skin dermis and blood than visible wavelengths. Therefore, laser irradiation using near-infrared wavelength may improve the therapeutic outcome of cutaneous hyper-vascular malformations in moderately to heavily pigmented skin patients and those with large-sized blood vessels or blood vessels extending deeply into the skin. A mathematical model composed of a Monte Carlo algorithm to estimate the distribution of absorbed light followed by numerical solution of a bio-heat diffusion equation was utilized to investigate the thermal response of human skin to near-infrared laser irradiation, and compared it with that to visible laser irradiation. Additionally, the effect of skin surface cooling on epidermal protection was theoretically investigated. Simulation results indicated that 940 nm wavelength is superior to 810 and 1064 nm in terms of the ratio of light absorption by targeted blood vessel to the absorption by the basal layer of epidermis, and is more efficient than 595 nm wavelength for the treatment of patients with large-sized blood vessels and moderately to heavily pigmented skin. Dermal blood content has a considerable effect on the laser-induced peak temperature at the basal layer of epidermis, while the effect of blood vessel size is minimum.

  18. Fast-response underwater TSP investigation of subcritical instabilities of a cylinder in crossflow

    NASA Astrophysics Data System (ADS)

    Capone, Alessandro; Klein, Christian; Di Felice, Fabio; Beifuss, Uwe; Miozzi, Massimo

    2015-10-01

    We investigate the classic cylinder in crossflow case to test the effectiveness of a fast-response underwater temperature-sensitive paint coating (TSP) in providing highly resolved spatial and time observations of the action of a flow over a bluff body surface. The flow is investigated at Reynolds number <190 k, before the onset of the drag-crisis state. The obtained TSP image sequences convey an accurate description of the evolution of the main features in the fluid-cylinder interaction, like the separation line position, the pattern of the large coherent structures acting on the cylinder's surface and the small-scale intermittent streamwise arrays of vortices. Ad hoc data management and features extraction techniques are proposed which allow extraction of quantitative data, such as separation line position and vortex-shedding frequency, and results are compared to the literature. Use of TSP for water applications introduces an interesting point of view about the fluid-body interactions by focusing directly on the effect of the flow on the model surface.

  19. Update on an investigation of flight buffeting of a variable-sweep aircraft. [F-111 A dynamic response

    NASA Technical Reports Server (NTRS)

    Benepe, D. B.; Cunningham, A. M., Jr.; Traylor, S., Jr.; Dunmyer, W. D.

    1975-01-01

    A detailed investigation of flight buffeting response of an F-111A aircraft was performed. AIAA Paper No. 74-358 presented results of an initial study of wing and fuselage responses measured at subsonic speeds and wing leading-edge sweep of 26 degrees. The present paper gives additional results for wing sweeps of 26, 50 and 72.5 degrees at Mach numbers up to 1.2 including horizontal tail responses. Power spectra, response time histories, variations of rms response with angle of attack, and effects of Mach number and wing sweep angle are discussed.

  20. Mitonuclear Ecology

    PubMed Central

    Hill, Geoffrey E.

    2015-01-01

    Eukaryotes were born of a chimeric union between two prokaryotes—the progenitors of the mitochondrial and nuclear genomes. Early in eukaryote evolution, most mitochondrial genes were lost or transferred to the nucleus, but a core set of genes that code exclusively for products associated with the electron transport system remained in the mitochondrion. The products of these mitochondrial genes work in intimate association with the products of nuclear genes to enable oxidative phosphorylation and core energy production. The need for coadaptation, the challenge of cotransmission, and the possibility of genomic conflict between mitochondrial and nuclear genes have profound consequences for the ecology and evolution of eukaryotic life. An emerging interdisciplinary field that I call “mitonuclear ecology” is reassessing core concepts in evolutionary ecology including sexual reproduction, two sexes, sexual selection, adaptation, and speciation in light of the interactions of mitochondrial and nuclear genomes. PMID:25931514

  1. What does remote sensing do for ecology?

    NASA Technical Reports Server (NTRS)

    Roughgarden, J.; Running, S. W.; Matson, P. A.

    1991-01-01

    The application of remote sensing to ecological investigations is briefly discussed. Emphasis is given to the recruitment problem in marine population dynamics, the regional analysis of terrestrial ecosystems, and the monitoring of ecological changes. Impediments to the use of remote sensing data in ecology are addressed.

  2. Investigating Assessment Bias for Constructed Response Explanation Tasks: Implications for Evaluating Performance Expectations for Scientific Practice

    NASA Astrophysics Data System (ADS)

    Federer, Meghan Rector

    Assessment is a key element in the process of science education teaching and research. Understanding sources of performance bias in science assessment is a major challenge for science education reforms. Prior research has documented several limitations of instrument types on the measurement of students' scientific knowledge (Liu et al., 2011; Messick, 1995; Popham, 2010). Furthermore, a large body of work has been devoted to reducing assessment biases that distort inferences about students' science understanding, particularly in multiple-choice [MC] instruments. Despite the above documented biases, much has yet to be determined for constructed response [CR] assessments in biology and their use for evaluating students' conceptual understanding of scientific practices (such as explanation). Understanding differences in science achievement provides important insights into whether science curricula and/or assessments are valid representations of student abilities. Using the integrative framework put forth by the National Research Council (2012), this dissertation aimed to explore whether assessment biases occur for assessment practices intended to measure students' conceptual understanding and proficiency in scientific practices. Using a large corpus of undergraduate biology students' explanations, three studies were conducted to examine whether known biases of MC instruments were also apparent in a CR instrument designed to assess students' explanatory practice and understanding of evolutionary change (ACORNS: Assessment of COntextual Reasoning about Natural Selection). The first study investigated the challenge of interpreting and scoring lexically ambiguous language in CR answers. The incorporation of 'multivalent' terms into scientific discourse practices often results in statements or explanations that are difficult to interpret and can produce faulty inferences about student knowledge. The results of this study indicate that many undergraduate biology majors

  3. The Effects of Student Response Systems on Performance and Satisfaction: An Investigation in a Tax Accounting Class

    ERIC Educational Resources Information Center

    Cummings, Richard G.; Hsu, Maxwell

    2007-01-01

    Does the use of student response systems (clickers) in the classroom increase student performance on exams? Do students perceive a benefit to using clickers in the classroom? This study investigates the effect of student response systems on accounting students' learning outcome and perceived satisfaction. Results show that, though the use of…

  4. Investigating the Clinical Usefulness of the Social Responsiveness Scale (SRS) in a Tertiary Level, Autism Spectrum Disorder Specific Assessment Clinic

    ERIC Educational Resources Information Center

    Aldridge, Fiona J.; Gibbs, Vicki M.; Schmidhofer, Katherine; Williams, Megan

    2012-01-01

    The Social Responsiveness Scale (SRS; Constantino and Gruber in Social Responsiveness Scale (SRS). Western Psychological Services, Los Angeles, 2005) is a commonly used screening tool for identifying children with possible autism spectrum disorder (ASD). This study investigated the relationship between SRS scores and eventual diagnostic outcome…

  5. Investigation of electrical responses to acupuncture stimulation: the effect of electrical grounding and insulation conditions.

    PubMed

    Lee, Yong-Heum; Ryu, Yeon-Hang; Jung, Byungjo

    2009-03-01

    Acupuncture in Oriental medicine has been widely used as a core therapeutic method due to its minimal side-effects and therapeutic efficacy. However, the electrical response to acupuncture stimulation (ERAS) has not been clearly studied under acupuncture conditions that might affect the efficacy of acupuncture therapy. In this study, the ERAS was objectively investigated by measuring meridian electric potentials (MEPs) when the electrical grounding conditions of the operator and subject were varied, and when the insulation conditions of acupuncture needle were varied. MEPs between Sang-geoheo (ST37) and Ha-geoheo (ST39) of the Stomach Meridian (ST) were measured by stimulating Jok-samni (ST36) with an acupuncture needle. For non-insulated acupuncture stimulation (NIAS), the average MEP peak was 148.6 +/- 20.6 when neither the operator nor the subject were electrically grounded, 23.1 +/- 8.8 when the subject only was electrically grounded, 348 +/- 76.8 when the operator only was electrically grounded, and 19.9 +/- 4.7 when both the operator and the subject were electrically grounded. The MEPs presented various magnitudes and patterns depending on the electrical grounding conditions. The MEP pattern was very similar to that of the charge and discharge of a capacitor. For insulated acupuncture stimulation (IAS), the average MEP peak was 20 +/- 4 in all electrical grounding conditions, which is not a significant electric response for acupuncture stimulation. In terms of electricity, this study verified that acupuncture therapy might be affected by acupuncture conditions such as (1) the electrical grounding condition of the operator and the subject and (2) the insulation condition of the acupuncture needle.

  6. Investigating the long-term geodetic response to magmatic intrusions at volcanoes in northern California

    NASA Astrophysics Data System (ADS)

    Parker, A. L.; Biggs, J.; Annen, C.; Houseman, G. A.; Yamasaki, T.; Wright, T. J.; Walters, R. J.; Lu, Z.

    2014-12-01

    Ratios of intrusive to extrusive activity at volcanic arcs are thought to be high, with estimates ranging between 5:1 and 30:1. Understanding the geodetic response to magmatic intrusion is therefore fundamental to large-scale studies of volcano deformation, providing insight into the dynamics of the inter-eruptive period of the volcano cycle and the building of continental crust. In northern California, we identify two volcanoes - Medicine Lake Volcano (MLV) and Lassen Volcanic Center (LaVC) - that exhibit long-term (multi-decadal) subsidence. We test the hypothesis that deformation at these volcanoes results from processes associated with magmatic intrusions. We first constrain the spatial and temporal characteristics of the deformation fields, establishing the first time-series of deformation at LaVC using InSAR data, multi-temporal analysis techniques and global weather models. Although the rates of deformation at the two volcanoes are similar (~1 cm/yr), our results show that the ratio of vertical to horizontal displacements is significantly different, suggesting contrasting source geometries. To test the origin of deformation, we develop modeling strategies to investigate thermal and viscoelastic processes associated with magmatic intrusions. The first model we develop couples analytical geodetic models to a numerical model of volume loss due to cooling and crystallization based upon temperature-melt fraction relationships from petrological experiments. This model provides evidence that magmatic intrusion at MLV has occurred more recently than the last eruption ~1 ka. The second model we test uses a finite element approach to simulate the time-dependent viscoelastic response of the crust to magmatic intrusion. We assess the magnitude and timescales of ground deformation that may result from these processes, exploring the model parameter space before applying the models to our InSAR observations of subsidence in northern California.

  7. Growth performance and gastrointestinal microbial ecology responses of piglets receiving Saccharomyces cerevisiae fermentation products after an oral challenge with Escherichia coli (K88).

    PubMed

    Kiarie, E; Bhandari, S; Scott, M; Krause, D O; Nyachoti, C M

    2011-04-01

    The effects of Saccharomyces cerevisiae fermentation products (YFP) on growth performance and gastrointestinal (GIT) microbial ecology in 90 weanling pigs orally challenged with Escherichia coli K88(+) (ETEC) were investigated. The YFP were an original YFP product (XPC) and a water-suspendable yeast fermentation prototype (WSYFP) from a commercial company. Treatments consisted of a negative control (NC, no in-feed or in-water additive), carbadox (AB, 55 mg of carbadox/kg of feed), XPC (in feed, 0.2%), and WSYFP (in water, 0.5, 1, or 2 g/pig per day), and each was allotted to 5 pens (3 pigs/pen). The diets met the 1998 NRC specifications. Pigs were acclimated to treatments for a 7-d period before an ETEC challenge. On d 8, blood was collected from pigs to determine the baseline packed cell volume (PCV) measurement, and pigs were orally challenged with ETEC. At various time points postchallenge, blood samples were taken, performance measures and fecal consistency scores were recorded, and gut digesta and tissue samples were taken to evaluate GIT morphology, microbial ecology, and metabolites. Preplanned contrasts were used for comparison. Pigs receiving YFP had greater ADFI than NC pigs on d 3 (424 vs. 378 g/d; P = 0.01) and d 7 (506 vs. 458 g/d; P = 0.03) postchallenge. This effect of YFP on ADFI was similar to that of AB on d 3, but pigs receiving AB ate more (576 vs. 506 g/d; P = 0.03) at d 7 than pigs receiving YFP. Pigs exhibited reduced (P < 0.001) PCV upon ETEC challenge; however, pigs receiving additives sustained a greater (P < 0.05) PCV at 72 h compared with the NC group. Compared with the NC pigs, pigs receiving YFP showed a smaller (P < 0.05) number of ileal mucosa adherent ETEC and prevalence of the order Enterobacteriales in the ileal digesta, which corresponded to less (5.09 vs. 6.97 mg/dL; P = 0.03) colonic ammonia on d 7 postchallenge. Most of the indices for ileal digesta bacterial richness and diversity were greater (P < 0.01) for YFP pigs compared

  8. Investigation of the interior of Mercury through the study of its gravity, topography, and tidal response

    NASA Astrophysics Data System (ADS)

    Padovan, Sebastiano

    With the goal of furthering our understanding of the interior structure of Mercury, this work tries to answer the following two questions. What can the response of the planet to solar tides reveal about the interior structure? What is the thickness of the crust and what are the implications for the interior? By comparing the models developed here for the tidal response of Mercury with the response measured by the MErcury Surface Space ENvironment GEochemistry and Ranging spacecraft (MESSENGER), the rheology of the mantle of the innermost planet is investigated. The measured tidal deformation indicates that, unless the rigidity of mantle materials is unexpectedly high, the mantle is relatively cold. Geochemical arguments based on the composition of the surface of Mercury as measured by MESSENGER have been used to put forward the hypothesis of the existence of a solid FeS layer at the bottom of the mantle. The tidal modeling indicates that the presence of the FeS layer is unlikely. To further constrain the interior structure of Mercury the thickness of the crust is calculated by computing geoid-to-topography ratios over the surface of the planet. The inferred crustal thickness, 35±18 km, has three interesting implications. First, this relatively thin crust allows for the possibility that basin-forming events excavated mantle material from Mercury's mantle. If this material is still exposed on the surface it can potentially be observed by instruments onboard MESSENGER and future missions at Mercury. Second, the volume of silicate materials present in the crust of Mercury represents about 10% of the total silicate materials in the planet, the largest value among the terrestrial planets. This implies that Mercury had the highest efficiency of crustal production. Finally, by combining the estimate of the crustal thickness with the measured abundances of heat-producing elements on the surface of Mercury a lower bound can be placed on the amount of heat production in the

  9. Investigating the drought-stress response of hybrid poplar genotypes by metabolite profiling.

    PubMed

    Barchet, Genoa L H; Dauwe, Rebecca; Guy, Robert D; Schroeder, William R; Soolanayakanahally, Raju Y; Campbell, Malcolm M; Mansfield, Shawn D

    2014-11-01

    Drought stress is perhaps the most commonly encountered abiotic stress plants experience in the natural environment, and it is one of the most important factors limiting plant productivity. Here, we employed untargeted metabolite profiling to examine four drought-stressed hybrid poplar (Populus spp.) genotypes for their metabolite content, using gas chromatography coupled to mass spectrometry. The primary objective of these analyses was to characterize the metabolite profile of poplar trees to assess relative drought resistance and to investigate the underlying biochemical mechanisms employed by the genotypes to combat drought. Metabolite profiling identified key metabolites that increased or decreased in relative abundance upon exposure to drought stress. Overall, amino acids, the antioxidant phenolic compounds catechin and kaempferol, as well as the osmolytes raffinose and galactinol exhibited increased abundance under drought stress, whereas metabolites involved in photorespiration, redox regulation and carbon fixation showed decreased abundance under drought stress. One clone in particular, Okanese, displayed unique responses to the imposed drought conditions. This clone was found to have higher leaf water potential, but lower growth rate relative to the other clones tested. Okanese also had lower accumulation of osmolytes such as raffinose, galactinol and proline, but higher overall levels of antioxidants such as catechin and dehydroascorbic acid. As such, it was proposed that osmotic adjustment as a mechanism for drought avoidance in this clone is not as well developed in comparison with the other clones investigated in this study, and that a possible alternative mechanism for the enhanced drought avoidance displayed by Okanese may be due to differential allocation of resources or better retention of water. PMID:24178982

  10. Investigating the zonal wind response to SST warming using transient ensemble AGCM experiments

    NASA Astrophysics Data System (ADS)

    Palipane, Erool; Lu, Jian; Staten, Paul; Chen, Gang; Schneider, Edwin K.

    2016-04-01

    The response of the atmospheric circulation to greenhouse gas-induced SST warming is investigated using large ensemble experiments with two AGCMs, with a focus on the robust feature of the poleward shift of the eddy driven jet. In these experiments, large ensembles of simulations are conducted by abruptly switching the SST forcing on from January 1st to focus on the wintertime circulation adjustment. A hybrid, finite amplitude wave activity budget analysis is performed to elucidate the nonlinear and irreversible aspects of the eddy-mean flow interaction during the adjustment of the zonal wind towards a poleward shifted state. The results confirm the results from earlier more idealized studies, particularly the importance of reduced dissipation of wave activity, in which the midlatitude decrease of effective diffusivity appears to be dominant. This reduction in dissipation increases the survival of midlatitude waves. These surviving waves, when reaching the upper propagation level in the upper troposphere, are subject to the influence of the increase of reflection phase speed at the poleward side of the mean jet, and thus more waves are reflected equatorward across the jet, giving rise to a poleward transport of momentum and thus an eddy momentum flux convergence for the poleward shift. The relative importance of wave breaking-induced PV mixing versus diabatic PV source in the evolution of the Lagrangian PV gradient is also investigated. The former plays the dominant role in the PV gradient formation during the initial phase of the jet shift, while the latter actually opposes the evolution of the Lagrangian PV gradient at times.

  11. Investigating the drought-stress response of hybrid poplar genotypes by metabolite profiling.

    PubMed

    Barchet, Genoa L H; Dauwe, Rebecca; Guy, Robert D; Schroeder, William R; Soolanayakanahally, Raju Y; Campbell, Malcolm M; Mansfield, Shawn D

    2014-11-01

    Drought stress is perhaps the most commonly encountered abiotic stress plants experience in the natural environment, and it is one of the most important factors limiting plant productivity. Here, we employed untargeted metabolite profiling to examine four drought-stressed hybrid poplar (Populus spp.) genotypes for their metabolite content, using gas chromatography coupled to mass spectrometry. The primary objective of these analyses was to characterize the metabolite profile of poplar trees to assess relative drought resistance and to investigate the underlying biochemical mechanisms employed by the genotypes to combat drought. Metabolite profiling identified key metabolites that increased or decreased in relative abundance upon exposure to drought stress. Overall, amino acids, the antioxidant phenolic compounds catechin and kaempferol, as well as the osmolytes raffinose and galactinol exhibited increased abundance under drought stress, whereas metabolites involved in photorespiration, redox regulation and carbon fixation showed decreased abundance under drought stress. One clone in particular, Okanese, displayed unique responses to the imposed drought conditions. This clone was found to have higher leaf water potential, but lower growth rate relative to the other clones tested. Okanese also had lower accumulation of osmolytes such as raffinose, galactinol and proline, but higher overall levels of antioxidants such as catechin and dehydroascorbic acid. As such, it was proposed that osmotic adjustment as a mechanism for drought avoidance in this clone is not as well developed in comparison with the other clones investigated in this study, and that a possible alternative mechanism for the enhanced drought avoidance displayed by Okanese may be due to differential allocation of resources or better retention of water.

  12. A Systematic Investigation of Accuracy and Response Time Based Measures Used to Index ANS Acuity

    PubMed Central

    Dietrich, Julia Felicitas; Huber, Stefan; Klein, Elise; Willmes, Klaus; Pixner, Silvia; Moeller, Korbinian

    2016-01-01

    The approximate number system (ANS) was proposed to be a building block for later mathematical abilities. Several measures have been used interchangeably to assess ANS acuity. Some of these measures were based on accuracy data, whereas others relied on response time (RT) data or combined accuracy and RT data. Previous studies challenged the view that all these measures can be used interchangeably, because low correlations between some of the measures had been observed. These low correlations might be due to poor reliability of some of the measures, since the majority of these measures are mathematically related. Here we systematically investigated the relationship between common ANS measures while avoiding the potential confound of poor reliability. Our first experiment revealed high correlations between all accuracy based measures supporting the assumption that all of them can be used interchangeably. In contrast, not all RT based measures were highly correlated. Additionally, our results revealed a speed-accuracy trade-off. Thus, accuracy and RT based measures provided conflicting conclusions regarding ANS acuity. Therefore, we investigated in two further experiments which type of measure (accuracy or RT) is more informative about the underlying ANS acuity, depending on participants’ preferences for accuracy or speed. To this end, we manipulated participants’ preferences for accuracy or speed both explicitly using different task instructions and implicitly varying presentation duration. Accuracy based measures were more informative about the underlying ANS acuity than RT based measures. Moreover, the influence of the underlying representations on accuracy data was more pronounced when participants preferred accuracy over speed after the accuracy instruction as well as for long or unlimited presentation durations. Implications regarding the diffusion model as a theoretical framework of dot comparison as well as regarding the relationship between ANS acuity and

  13. A Systematic Investigation of Accuracy and Response Time Based Measures Used to Index ANS Acuity.

    PubMed

    Dietrich, Julia Felicitas; Huber, Stefan; Klein, Elise; Willmes, Klaus; Pixner, Silvia; Moeller, Korbinian

    2016-01-01

    The approximate number system (ANS) was proposed to be a building block for later mathematical abilities. Several measures have been used interchangeably to assess ANS acuity. Some of these measures were based on accuracy data, whereas others relied on response time (RT) data or combined accuracy and RT data. Previous studies challenged the view that all these measures can be used interchangeably, because low correlations between some of the measures had been observed. These low correlations might be due to poor reliability of some of the measures, since the majority of these measures are mathematically related. Here we systematically investigated the relationship between common ANS measures while avoiding the potential confound of poor reliability. Our first experiment revealed high correlations between all accuracy based measures supporting the assumption that all of them can be used interchangeably. In contrast, not all RT based measures were highly correlated. Additionally, our results revealed a speed-accuracy trade-off. Thus, accuracy and RT based measures provided conflicting conclusions regarding ANS acuity. Therefore, we investigated in two further experiments which type of measure (accuracy or RT) is more informative about the underlying ANS acuity, depending on participants' preferences for accuracy or speed. To this end, we manipulated participants' preferences for accuracy or speed both explicitly using different task instructions and implicitly varying presentation duration. Accuracy based measures were more informative about the underlying ANS acuity than RT based measures. Moreover, the influence of the underlying representations on accuracy data was more pronounced when participants preferred accuracy over speed after the accuracy instruction as well as for long or unlimited presentation durations. Implications regarding the diffusion model as a theoretical framework of dot comparison as well as regarding the relationship between ANS acuity and

  14. Metabolomics in chemical ecology.

    PubMed

    Kuhlisch, Constanze; Pohnert, Georg

    2015-07-01

    Chemical ecology elucidates the nature and role of natural products as mediators of organismal interactions. The emerging techniques that can be summarized under the concept of metabolomics provide new opportunities to study such environmentally relevant signaling molecules. Especially comparative tools in metabolomics enable the identification of compounds that are regulated during interaction situations and that might play a role as e.g. pheromones, allelochemicals or in induced and activated defenses. This approach helps overcoming limitations of traditional bioassay-guided structure elucidation approaches. But the power of metabolomics is not limited to the comparison of metabolic profiles of interacting partners. Especially the link to other -omics techniques helps to unravel not only the compounds in question but the entire biosynthetic and genetic re-wiring, required for an ecological response. This review comprehensively highlights successful applications of metabolomics in chemical ecology and discusses existing limitations of these novel techniques. It focuses on recent developments in comparative metabolomics and discusses the use of metabolomics in the systems biology of organismal interactions. It also outlines the potential of large metabolomics initiatives for model organisms in the field of chemical ecology.

  15. The Autoimmune Ecology

    PubMed Central

    Anaya, Juan-Manuel; Ramirez-Santana, Carolina; Alzate, Maria A.; Molano-Gonzalez, Nicolas; Rojas-Villarraga, Adriana

    2016-01-01

    Autoimmune diseases (ADs) represent a heterogeneous group of disorders that affect specific target organs or multiple organ systems. These conditions share common immunopathogenic mechanisms (i.e., the autoimmune tautology), which explain the clinical similarities they have among them as well as their familial clustering (i.e., coaggregation). As part of the autoimmune tautology, the influence of environmental exposure on the risk of developing ADs is paramount (i.e., the autoimmune ecology). In fact, environment, more than genetics, shapes immune system. Autoimmune ecology is akin to exposome, that is all the exposures – internal and external – across the lifespan, interacting with hereditary factors (both genetics and epigenetics) to favor or protect against autoimmunity and its outcomes. Herein, we provide an overview of the autoimmune ecology, focusing on the immune response to environmental agents in general, and microbiota, cigarette smoking, alcohol and coffee consumption, socioeconomic status (SES), gender and sex hormones, vitamin D, organic solvents, and vaccines in particular. Inclusion of the autoimmune ecology in disease etiology and health will improve the way personalized medicine is currently conceived and applied. PMID:27199979

  16. The Autoimmune Ecology.

    PubMed

    Anaya, Juan-Manuel; Ramirez-Santana, Carolina; Alzate, Maria A; Molano-Gonzalez, Nicolas; Rojas-Villarraga, Adriana

    2016-01-01

    Autoimmune diseases (ADs) represent a heterogeneous group of disorders that affect specific target organs or multiple organ systems. These conditions share common immunopathogenic mechanisms (i.e., the autoimmune tautology), which explain the clinical similarities they have among them as well as their familial clustering (i.e., coaggregation). As part of the autoimmune tautology, the influence of environmental exposure on the risk of developing ADs is paramount (i.e., the autoimmune ecology). In fact, environment, more than genetics, shapes immune system. Autoimmune ecology is akin to exposome, that is all the exposures - internal and external - across the lifespan, interacting with hereditary factors (both genetics and epigenetics) to favor or protect against autoimmunity and its outcomes. Herein, we provide an overview of the autoimmune ecology, focusing on the immune response to environmental agents in general, and microbiota, cigarette smoking, alcohol and coffee consumption, socioeconomic status (SES), gender and sex hormones, vitamin D, organic solvents, and vaccines in particular. Inclusion of the autoimmune ecology in disease etiology and health will improve the way personalized medicine is currently conceived and applied.

  17. Cascading ecological effects of eliminating fishery discards

    PubMed Central

    Heath, Michael R.; Cook, Robin M.; Cameron, Angus I.; Morris, David J.; Speirs, Douglas C.

    2014-01-01

    Discarding by fisheries is perceived as contrary to responsible harvesting. Legislation seeking to end the practice is being introduced in many jurisdictions. However, discarded fish are food for a range of scavenging species; so, ending discarding may have ecological consequences. Here we investigate the sensitivity of ecological effects to discarding policies using an ecosystem model of the North Sea—a region where 30–40% of trawled fish catch is currently discarded. We show that landing the entire catch while fishing as usual has conservation penalties for seabirds, marine mammals and seabed fauna, and no benefit to fish stocks. However, combining landing obligations with changes in fishing practices to limit the capture of unwanted fish results in trophic cascades that can benefit birds, mammals and most fish stocks. Our results highlight the importance of considering the broader ecosystem consequences of fishery management policy, since species interactions may dissipate or negate intended benefits. PMID:24820200

  18. Kinetic investigation and lifetime prediction of Cs-NIPAM-MBA-based thermo-responsive hydrogels.

    PubMed

    Othman, Muhammad Bisyrul Hafi; Khan, Abbas; Ahmad, Zulkifli; Zakaria, Muhammad Razlan; Ullah, Faheem; Akil, Hazizan Md

    2016-01-20

    This study attempted to clarify the influence of a cross-linker, N,N-methylenebisacrylamide (MBA), and N-isopropylacrylamide (NIPAM) on the non-isothermal kinetic degradation, solid state and lifetime of hydrogels using the Flynn-Wall-Ozawa (F-W-O), Kissinger, and Coats-Redfern (C-Red) methods. The series of dual-responsive Cs-PNIPAM-MBA microgels were synthesized by soapless-emulsion free radical copolymerization in an aqueous medium at 70 °C. The thermal properties were investigated using thermogravimetric analysis (TG) and differential scanning calorimetry (DSC) under nitrogen atmosphere. The apparent activation energy using the chosen Flynn-Wall-Ozawa and Kissinger methods showed that they fitted each other. Meanwhile, the type of solid state mechanism was determined using the Coats-Redfern method proposed for F1 (pure Cs) and F2 (Cs-PNIPAM-MBA hydrogel series) types, which comprise random nucleation with one nucleus reacting on individual particles, and random nucleation with two nuclei reacting on individual particles, respectively. On average, a higher Ea was attributed to the greater cross-linking density of the Cs hydrogel.

  19. In vitro investigations on the effect of dermal fibroblasts on keratinocyte responses to ultraviolet B radiation.

    PubMed

    Fernandez, Tara L; Van Lonkhuyzen, Derek R; Dawson, Rebecca A; Kimlin, Michael G; Upton, Zee

    2014-01-01

    Exposure to ultraviolet radiation is closely linked to the development of skin cancers in humans. The ultraviolet B (UVB) radiation wavelength (280-320 nm), in particular, causes DNA damage in epidermal keratinocytes, which are linked to the generation of signature premalignant mutations. Interactions between dermal fibroblasts and keratinocytes play a role in epidermal repair and regeneration after UVB-induced damage. To investigate these processes, established two and three-dimensional culture models were utilized to study the impact of fibroblast-keratinocyte crosstalk during the acute UVB response. Using a coculture system it was observed that fibroblasts enhanced keratinocyte survival and the repair of cyclobutane pyrimidine dimers (CPDs) after UVB radiation exposure. These findings were also mirrored in irradiated human skin coculture models employed in this study. Fibroblast coculture was shown to play a role in the expression and activation of members of the apoptotic cascade, including caspase-3 and Bad. Interestingly, the expression and phosphorylation of p53, a key player in the regulation of keratinocyte cell fate postirradiation, was also shown to be influenced by fibroblast-produced factors. This study highlights the importance of synergistic interactions between fibroblasts and keratinocytes in maintaining a functional epidermis while promoting repair and regeneration following UVB radiation-induced damage.

  20. Shock tube investigation of dynamic response of pressure transducers for validation of rotor performance measurements

    NASA Technical Reports Server (NTRS)

    Bershader, Daniel

    1988-01-01

    For some time now, NASA has had a program under way to aid in the validation of rotor performance and acoustics codes associated with the UH-60 rotary-wing aircraft; and to correlate results of such studies with those obtained from investigations of other selected aircraft rotor performance. A central feature of these studies concerns the dynamic measurement of surface pressure at various locations up to frequencies of 25 KHz. For this purpose, fast-response