79717 research outputs found
Sort by
Strain-specific effects of the herbicide RoundUp on diverse natural isolates of Saccharomyces cerevisiae
Get PDFThe safety of the chemical glyphosate, the active ingredient in the herbicide RoundUpTM, has been questioned on numerous occasions. Previous studies suggest that glyphosate-containing herbicides have deleterious effects on a variety of organisms; other studies suggest that these effects may be minor, transient, or non-existent altogether. Proper maintenance of microbial soil communities is imperative to agricultural success; yeasts can play an important role in these communities. Studies involving the brewer's yeast Saccharomyces cerevisiae have the ability to model eukaryotes, microbes, genetics, systems-level genomics, as well as to inspect yeasts themselves. Therefore, studying the effects of RoundUpTM on S. cerevisiae may provide direct insight into the potential effects of RoundUpTM on soil yeast health, and indirect insight into the effects of RoundUpTM on non-target organisms including other soil microbes and eukaryotes. Here, we characterize the effects of RoundUpTM on 12 genetically diverse isolates of S. cerevisiae. Growth assays in media with and without RoundUpTM indicate that the herbicide inhibits growth in all strains, but the magnitude of this inhibition is variable among strains. Our results suggest that the genetic basis for RoundUpTM resistance is strain-specific in S. cerevisiae, inviting further study into genetic variants that may be useful in applied contexts.
Key Words: RoundUpTM, glyphosate, Saccharomyces cerevisia
Characterizing PM2.5 with Different Source Contributions
No full textUbiquitous fine particulate matter (PM2.5) exposures significantly impact global public health, yet little is known about the mechanisms causing these known adverse health effects. Oxidative stress due to PM2.5 associated chemical constituents, such as polycyclic aromatic hydrocarbons (PAHs), is a proposed possible mechanism for PM2.5 mediated health effects. Variations in the ability to induce oxidative stress have been previously identified in PM2.5 air filter samples and these variations may be attributed to the differing source contributions and thus chemical constituents of PM2.5. To test this hypothesis, PM2.5 filters collected at locations with differing predominant sources were assessed for oxidative potential, chemical composition, and developmental toxicity. Sampling locations included an outdoor rural park across seasons, two vehicular traffic influenced locations and 32 indoor homes in India. PM2.5 was extracted from filters via sonication in methanol. Aliquots of individual filter samples were removed to measure oxidative potential using the dithiothreitol (DTT) assay. Samples were then pooled by location for chemical analysis of PAHs (n=115) and elements (n=20). Pooled samples were also prepared for developmental toxicity testing in zebrafish starting at 6 hours post fertilization (hpf) to assess morphological and behavioral changes at 24 and 120 hpf. Significant variation in chemical constituents between locations of differing sources was observed. Significant differences in oxidative potential were observed between both individual filters and sample sites. Samples sites showed significantly different toxicities, inducing both morphological and behavioral effects in zebrafish at varying concentration ranges between sources. This research will ultimately lead to a greater understanding of health-relevant metrics for PM2.5 exposures and the potential impacts of various PM2.5 sources.Key Words: air pollution, particulate matter, toxicology, PA
SNP data for 295 snap bean genotypes utilized in a study of snap bean genetic diversity published in Genes
No full textThe accessions used in this study were comprised of 246 snap bean and 49 dry bean genotypes. Of these, 150 snap bean accessions came from the Common Bean Coordinated Agriculture Project Snap Bean Diversity panel, an assemblage of 59 Chinese snap bean genotypes obtained from a trip to China in 1991 by Michael Dickson (Cornell University), placed in the United States Dept. of Agriculture National Plant Germplasm System (USDA-NPGS) Plant Introduction collection at Pullman, WA, USA, but left uncatalogued and provided to the Oregon State University (OSU) Vegetable Breeding Program for evaluation, 19 genotypes obtained from the Misión Biológica de Galicia—Consejo Superior de Investigaciones Científicas (CSIC) (Pontevedra, Spain) collection, and 24 heirloom snap beans obtained from specialized seed catalogs and the family of Harvey Bruxvoort. For the dry beans, the 49 accessions chosen were selected based on having been previously reported to belong to one of six bean races. DNA of accessions was isolated, quantified and analyzed using Illumina Infinium Genechip BARCBEAN6K_3 platform. This SNP array consists of 5,398 allele-specific probes. The raw data was processed using GenomeStudio (v2.0.4) software (Illumina, San Diego, CA USA). Two marker positions contained greater than 20% missing data and were removed from the study resulting in 5,396 SNPs. Heterozygous positions were treated as missing data and four Chinese genotypes with greater than 20% missing data were removed from the study. No imputation of the data was conducted
Influence of Uncertainties in Terrestrial Laser Scanning on Structural Reliability and Bridge Load Rating - Finite Element Models (FEM)
No full textThis dataset includes the finite element models (FEMs) used for the MS Thesis entitled: Influence of Uncertainties in Terrestrial Laser Scanning on Structural Reliability and Bridge Load Rating by Carly K. Loving. These FEMs were created in SAP 2000
and contain models from both thesis manuscripts. The following lists summarizes the files and a brief description. For more information on these models, please refer to https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/vm40z0370
- Manuscript1_ReferenceDimensions_Linear: Linear Torsional FEM of the Steel Specimen using the Reference Dimensions
- Manuscript1_ReferenceDimensions_Nonlinear: Nonlinear Torsional FEM of the Steel Specimen using the Reference Dimensions
- Manuscript1_TLSDimensions_Linear: Linear Torsional FEM of the Steel Specimen using the TLS Based Dimensions
- Manuscript1_TLSDimensions_Nonlinear: Nonlinear Torsional FEM of the Steel Specimen using the TLS Based Dimensions
- Manuscript2_ReferenceDimensions_Luckiamute: Luckiamute River Bridge FEM using Reference Dimensions for Vehicular Live Loading
- Manuscript2_TLSDimensions_Luckiamute: Luckiamute River Bridge FEM using TLS Based Dimensions for Vehicular Live Loadin
Utilization of Renewable Energy via Thermochemistry
Get PDFUtilization of solar energy or wind energy for electricity production is inherently challenging due to the diurnal and seasonal variations and normal intermittency. Effective, high efficiency storage methods need to be developed for further advancing renewable energy utilization. Endothermic chemical processing and thermochemical energy storage can be both employed as strategies to utilize renewable energy. Although chemical processing can be carried out via direct solar irradiation, indirect application of process heat on a 24/7 basis would be much more amicable for the chemical industry. Thermochemical energy storage is needed to enable dispatchable and reliable heat generation for continuous chemical processing. Thermochemical energy storage (TCES) offers inherently greater energy density than sensible or latent heat thermal storage methods by virtue of storing energy in chemical bonds, but currently suffers from gas storage requirements and materials longevity issues. Another method of energy storage, conventional Compressed Air Energy Storage (CAES) method, suffers from low efficiencies inherent in compression, heat loss during storage, and the commonly employed natural gas-fired reheat prior to expansion.
To address these issues, three topics were investigated with the goal of utilizing of renewable energy through thermochemistry:
(1) Ethylene production via solar-driven ethane cracking at 800-1000°C
(2) An in-depth investigation of BaO₂/BaO redox oxides for reversible solar thermochemical energy storage
(3) Thermochemical heat recuperation for compressed air energy storag
A New Tool and a New Look at Human Relationships with Nature: from Biophilia to Behavior Change
Get PDFDespite some successful conservation stories, biodiversity continues to be lost around the world. Climate change accentuates the ecological crisis and demands not only coordinated action by individuals and collectives, but also a re-examination (and re-imagination) of our relationship with nature. As part of the basis for such a re-examination, further progress is needed to elucidate the determinants of environmentally conscious behavior, from the origins of biophilia to the barriers that lie between intention to live sustainably and success in doing so.
In this dissertation, I develop a new tool to investigate the origins of human-nature relationships and, through two exploratory studies, I attempt to advance our understanding of the determinants of pro-environmental behaviors. Lastly, and perhaps most important of all, I discuss the role of individual environmental behaviors vs behaviors that promote systemic change.
In the first study, I developed, with my collaborators, a new multifaceted scale to measure the contribution of key childhood experiences to the development of love and care for nature. We built on the concept of Significant Life Experiences (SLEs), designing what we have called the Roots of Biophilia and Interest in Nature (ROBIN) scale, which has shown good psychometric properties and proven to be a reliable and valid measure. We confirmed the existence of six roots of biophilia and discuss the importance of fomenting childhood experiences that instill love for nature in future generations.
In the second study, we investigated the carbon footprint of West Coast Environmentalists. We selected this group as being likely to have both the knowledge and the intention to behave sustainably, but we confirmed findings from elsewhere that even environmentalists themselves find it difficult to ‘walk the talk’. We compared their carbon footprint with those of other residents and offer a preliminary account of the barriers environmentalists perceived to adopting pro-environmental behaviors. We found no correlation between intentions and actual behaviors in either group. As expected, the most relevant barriers identified by environmentalists varied across domains, yet perceived lack of choice and complicated logistics were notably important. We discuss how barriers may be overcome and the need for further studies on barriers to inform specific climate policies and interventions.
In the third study we continued to investigate differences between West Coast environmentalists and other residents. In this study we shift the focus from individual emissions to assess how both groups differ in their engagement in behaviors oriented more towards systemic change than personal emissions reductions. Our results showed that environmentalists engaged significantly more in eight different types of pro-environmental behaviors, from protesting to donating money to environmental NGOs. They were also significantly more likely to support systemic changes via climate policies and regulations, and they ascribed significantly more responsibility for climate action to different actors in society, from citizens to governments. We discuss the focus on individual behaviors in the climate crisis, and the importance of pursuing systemic change through engaged citizenship.
Our results contribute to the growing body of work in the field of environmental psychology on human-nature relationships and environmental behavior. The ROBIN scale, a quantitative tool to examine the roots of biophilia and interest in nature across different populations, could help to target interventions to foster reconnection with nature, especially among children living in urban and often nature-deprived spaces. Our results on the barriers for pro-environmental behaviors offer a preliminary account of key regional barriers to the adoption of pro-environmental behaviors. Finally, we confirm that even environmentalists struggle to adopt pro-environmental behaviors, but that they are much more likely than others to engage in informed advocacy, activism, and other behaviors
Automation-Aided Collaborative Strategies in Signal Detection Tasks
Get PDFAutomated systems have become increasingly important to human decision making and task performance in a wide variety of complex fields and situations. Decision aids, a specific form of automation, assist human operators in making complex decisions under conditions of uncertainty, such as air traffic control or combat identification. When humans collaborate with other humans in decision making tasks, they are typically plagued by inefficiencies in decision weighting, information integration, and confidence calibration. The collaborative process by which a human operator uses an automated decision aid is similarly inefficient; past research investigating the efficacy of decision aids has suggested that individuals fail to use the information provided by an aid in an ideal manner, reaching levels of performance below ideal statistical predictions of automation use. As automation is increasingly employed in both everyday and professional settings, it is of crucial importance to understand how operators use automated decision aids, and what decision-making strategies they employ. Research examining competing explanations of automation-aided decision making is conflicted, and has disagreed as to what information provided by an aid are used by human operators. To inform automation design, it is therefore important to understand the decision-making process used by operators during automation use. The present project examined automation-aided human performance in a pair of signal detection tasks, to contrast a series of cognitive process models that provide plausible explanations of aid use. Study 1 fit automation-aided human signal detection performance to psychometric curves in a hierarchical Bayesian parameter estimation procedure, to compare the competing contingent criterion and discrete state decision strategies. Results from 143 participants found that the lack of increase in attentional lapses for aided performance was most consistent with a contingent criterion strategy of automation use, but changes in bias were observed that were inconsistent with both models. Study 2 fit automation-aided performance to a series of formal cognitive process models, comparing several plausible models of automation-use strategies and heuristics. Results from 123 participants indicated that a novel integrated confidence mixture model was the best fit to the observed data. Study 3 replicated these findings, and found in 104 participants that the integrated confidence model was also the best fit to the observed data for both a 93% and 84% reliable decision aid. The results of this project suggest that when performing a signal detection task with assistance from a decision aid, operators engage in a criterion shifting strategy, while occasionally lapsing and deferring to the aid’s judgment with a probability equal to the aid’s confidence on a given trial. Consistent with research that suggests confidence sharing is an integral part of human-human collaboration, these results suggest aid confidence information is valuable to operators, and is indeed used during automation-aided decision-making
Forest Decentralization in Ghana: Examining Empowerment of Local Institutions
Get PDFDecentralizing resource control for community-based natural resource management (CBNRM) is a widely promoted scheme for natural resource governance worldwide. Researchers and policymakers have suggested that this approach has the potential to achieve positive social outcomes and succeed where centralized resource conservation has been inadequate. In reality, the powers transferred are not always as theorized, and the outcomes of these schemes are a mix of success and failures on social and ecological performance. In this exploratory study, I sought to examine the powers transferred to Community Resource Management Areas (CREMAs) in Ghana and the transferred powers' outcomes. I used a qualitative research design and interviewed research participants in Ghana at the National and District levels and three selected CREMAs from the west of the High Forest Zone in Ghana. I also approached this work from a critical research paradigm. The results show that CREMAs have and exercise extensive powers to enforce restrictions on local use of forest resources, but have limited decision-making, law-making, or adjudication powers over resources. CREMAs consequently appear to be a vehicle for achieving the Forestry Commission's conservation objectives rather than pursue the socio-political opportunities for forest communities through resource management. The results also show that CREMAs impact on communities is weak. There is no focus on enhancing forest communities' political awareness to exercise choice and self-determination over their resource rights. There is the need for a political approach to CREMAs, which fully considers their marginalized position in resource decision making, to give them real local control over resources and support. Local CREMA communities need far greater rights compared to the claims of what is currently given. External actors, particularly NGOs, need to support communities to realize their resource rights and utilize their natural resources to create wealth locally. These findings also show the need for greater coherence between decentralizing forest and the political decentralization process. This thesis also provides useful feedback for the CREMA reform process and makes theoretical and practical contributions to CBNRM and CREMA literature
The Nature of the Discourse on Race and Ethnicity in Play Therapy Literature
Get PDFEthical and training standards across counseling-related professions contain competencies related to race and ethnicity as necessary research and practice components. One such counseling-related sub-specialty is Play Therapy, which acknowledges that professionals utilizing play therapy techniques must consider racial and cultural context, trauma, and intersectionality when working with children. However, there is no research about whether the discourse on race and ethnicity can be detected in play therapy academic writing. A corpus linguistic research approach provides an opportunity to understand the various emotional and cognitive patterns and attitudes embedded in writing content to take stock of the writer's relationship with readers concerning multiculturalism, race, and ethnicity. This dissertation represents the first effort to analyze language in play therapy discourse and further investigate the relationship play therapy writers offer to readers concerning race and ethnicity. The core of the dissertation is two empirical research manuscripts, one examining psycholinguistic elements of the International Journal of Play Therapy (IJPT) and the other exploring the authorial stance of writers who publish in the IJPT. The IJPT 400-article corpus was divided into two corpuses: one with articles that have race and ethnicity as a topic (RE) and articles that do not (NRE). For the first study, linguistic and psychological processes in play therapy articles published in IJPT were analyzed using the LIWC computer software. Findings indicated that writers of RE and NRE articles aim to distance themselves from their research and tend to present their research with a positive tone. A surprising finding, given the historical experiences and consequences of race-based harms was that RE writers use less negative emotion when discussing race and ethnicity. The second study explored the use of authorial stance, hedges, boosters, and attitude markers among RE and NRE articles in the IJPT. Regarding the level of expressing commitment/tentativeness and signaling authorial presence, regardless of the topic, IJPT writers tend to create ambiguity in their stance toward their research. The test of the difference in the use of attitude markers between RE and NRE articles showed a substantial level of difference between the subcorpuses. In terms of the required thematic linkage between the manuscripts of the dissertation, both studies begin to clarify the language, attitudes, beliefs, and intentions that writers offer about race and ethnicity to readers and mental health trainees