158 research outputs found
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Assessing Policy Innovation: Climate Action Planning in the U.S. Southwest
Cities are on the front lines of climate change, and local climate action planning has the potential to both reduce greenhouse gas emissions through mitigation and reduce vulnerability to climate risk through climate adaptation. A growing body of planning research has explored climate action planning but has primarily focused on dedicated climate action plans and generally relied upon a narrow sample of coastal and larger cities that do not represent the diversity of cities that planners serve within the United States. This dissertation focuses on climate action planning in arid lands with an overarching research question: How are cities in the U.S. Southwest planning for climate change? The original research I present in this dissertation addresses this question through three interrelated papers that assess the state of planning literature on climate action planning research (Appendix A), document the concerns, approaches, and catalyst and barriers planners report facing when addressing climate risk (Appendix B), and evaluate how climate action planning is being mainstreamed into comprehensive plans (Appendix C). This dissertation advances planning scholarship and practice by expanding the understanding of climate action planning in cities in the arid lands of the U.S. Southwest
Webinar: Assessing Cool Corridor Heat Resilience Strategies for Human-Scale Transportation
Heat is the number one weather-related killer in the United States, and the implications of heat impacts range from individual transportation users, to emergency management services, and entire transportation networks and systems. In this presentation, we\u27ll cover key concepts for urban planning and heat resilience, including heat mitigation and management strategies. Additionally, we will discuss the original NITC-sponsored data collection evaluating one such cool corridor strategy--PlusTI cool pavement rejuvenator--and the associated challenges of researching impacts of strategies on human-comfort in natural and built environments.https://pdxscholar.library.pdx.edu/trec_webinar/1073/thumbnail.jp
Birch bark tar in early Medieval England:continuity of tradition or technological revival?
International audienc
Where did the votes go? Reassessing American party realignments via vote transfers between major parties from 1860 to 2008
Political scientists have long debated theories of electoral party realignments. In this paper, we apply ecological inference methods to statistically analyze the transfer of votes within counties in US presidential elections since 1860. Through this analysis we are able to identify the major periods of party realignment in US history and the counties where these shifts took place. As a result, we are able to provide new insights into American electoral history, and provide strong evidence that the 2008 presidential election did not represent a realigning election as the phrase is generally understood
Comparative Transcriptional Network Modeling of Three PPAR-α/γ Co-Agonists Reveals Distinct Metabolic Gene Signatures in Primary Human Hepatocytes
Aims:
To compare the molecular and biologic signatures of a balanced dual peroxisome proliferator-activated receptor (PPAR)-α/γ agonist, aleglitazar, with tesaglitazar (a dual PPAR-α/γ agonist) or a combination of pioglitazone (Pio; PPAR-γ agonist) and fenofibrate (Feno; PPAR-α agonist) in human hepatocytes.
Methods and Results:
Gene expression microarray profiles were obtained from primary human hepatocytes treated with EC50-aligned low, medium and high concentrations of the three treatments. A systems biology approach, Causal Network Modeling, was used to model the data to infer upstream molecular mechanisms that may explain the observed changes in gene expression. Aleglitazar, tesaglitazar and Pio/Feno each induced unique transcriptional signatures, despite comparable core PPAR signaling. Although all treatments inferred qualitatively similar PPAR-α signaling, aleglitazar was inferred to have greater effects on high- and low-density lipoprotein cholesterol levels than tesaglitazar and Pio/Feno, due to a greater number of gene expression changes in pathways related to high-density and low-density lipoprotein metabolism. Distinct transcriptional and biologic signatures were also inferred for stress responses, which appeared to be less affected by aleglitazar than the comparators. In particular, Pio/Feno was inferred to increase NFE2L2 activity, a key component of the stress response pathway, while aleglitazar had no significant effect. All treatments were inferred to decrease proliferative signaling.
Conclusions:
Aleglitazar induces transcriptional signatures related to lipid parameters and stress responses that are unique from other dual PPAR-α/γ treatments. This may underlie observed favorable changes in lipid profiles in animal and clinical studies with aleglitazar and suggests a differentiated gene profile compared with other dual PPAR-α/γ agonist treatments
Small molecule activators of SIRT1 replicate signaling pathways triggered by calorie restriction in vivo
<p>Abstract</p> <p>Background</p> <p>Calorie restriction (CR) produces a number of health benefits and ameliorates diseases of aging such as type 2 diabetes. The components of the pathways downstream of CR may provide intervention points for developing therapeutics for treating diseases of aging. The NAD<sup>+</sup>-dependent protein deacetylase SIRT1 has been implicated as one of the key downstream regulators of CR in yeast, rodents, and humans. Small molecule activators of SIRT1 have been identified that exhibit efficacy in animal models of diseases typically associated with aging including type 2 diabetes. To identify molecular processes induced in the liver of mice treated with two structurally distinct SIRT1 activators, SIRT501 (formulated resveratrol) and SRT1720, for three days, we utilized a systems biology approach and applied Causal Network Modeling (CNM) on gene expression data to elucidate downstream effects of SIRT1 activation.</p> <p>Results</p> <p>Here we demonstrate that SIRT1 activators recapitulate many of the molecular events downstream of CR <it>in vivo</it>, such as enhancing mitochondrial biogenesis, improving metabolic signaling pathways, and blunting pro-inflammatory pathways in mice fed a high fat, high calorie diet.</p> <p>Conclusion</p> <p>CNM of gene expression data from mice treated with SRT501 or SRT1720 in combination with supporting <it>in vitro </it>and <it>in vivo </it>data demonstrates that SRT501 and SRT1720 produce a signaling profile that mirrors CR, improves glucose and insulin homeostasis, and acts via SIRT1 activation <it>in vivo</it>. Taken together these results are encouraging regarding the use of small molecule activators of SIRT1 for therapeutic intervention into type 2 diabetes, a strategy which is currently being investigated in multiple clinical trials.</p
The Role of Hypoxia in 2-Butoxyethanol–Induced Hemangiosarcoma
To understand the molecular mechanisms underlying compound-induced hemangiosarcomas in mice, and therefore, their human relevance, a systems biology approach was undertaken using transcriptomics and Causal Network Modeling from mice treated with 2-butoxyethanol (2-BE). 2-BE is a hemolytic agent that induces hemangiosarcomas in mice. We hypothesized that the hemolysis induced by 2-BE would result in local tissue hypoxia, a well-documented trigger for endothelial cell proliferation leading to hemangiosarcoma. Gene expression data from bone marrow (BM), liver, and spleen of mice exposed to a single dose (4 h) or seven daily doses of 2-BE were used to develop a mechanistic model of hemangiosarcoma. The resulting mechanistic model confirms previous work proposing that 2-BE induces macrophage activation and inflammation in the liver. In addition, the model supports local tissue hypoxia in the liver and spleen, coupled with increased erythropoeitin signaling and erythropoiesis in the spleen and BM, and suppression of mechanisms that contribute to genomic stability, events that could be contributing factors to hemangiosarcoma formation. Finally, an immunohistochemistry method (Hypoxyprobe) demonstrated that tissue hypoxia was present in the spleen and BM. Together, the results of this study identify molecular mechanisms that initiate hemangiosarcoma, a key step in understanding safety concerns that can impact drug decision processes, and identified hypoxia as a possible contributing factor for 2-BE–induced hemangiosarcoma in mice
Academically buoyant students are less anxious about and perform better in high-stakes examinations.
BACKGROUND: Prior research has shown that test anxiety is negatively related to academic buoyancy, but it is not known whether test anxiety is an antecedent or outcome of academic buoyancy. Furthermore, it is not known whether academic buoyancy is related to performance on high-stakes examinations. AIMS: To test a model specifying reciprocal relations between test anxiety and academic buoyancy and to establish whether academic buoyancy is related to examination performance. SAMPLE: A total of 705 students in their final year of secondary education (Year 11). METHODS: Self-report data for test anxiety and academic buoyancy were measured in two waves in Year 11. Examination performance was taken from the mean English, mathematics, and science scores from the high-stakes General Certificate of Secondary Education (GCSE) examinations taken at the end of Year 11. RESULTS: Measurement invariance was demonstrated for test anxiety and academic buoyancy across both waves of measurement. The worry component of test anxiety, but not the tension component, showed reciprocal relations with academic buoyancy. Worry predicted lower mean GCSE score and academic buoyancy predicted a higher mean GCSE score. Tension did not predict mean GCSE score. CONCLUSION: Academic buoyancy protects against the appraisal of examinations as threatening by influencing self-regulative processes and enables better examination performance. Worry, but not tension, shows a negative feedback loop to academic buoyancy
Neighborhood Racial Characteristics, Credit History, and Bankcard Credit in Indian Country
We examine whether concerns about lenders’ discrimination based on community racial characteristics can be empirically substantiated in the context of neighborhoods on and near American Indian reservations. Drawing on a large-scale dataset consisting of individual-level credit bureau records, we find that residing in a predominantly American Indian neighborhood is ceteris paribus associated with worse bankcard credit outcomes than residing in a neighborhood where the share of American Indian residents is low. While these results are consistent with the possibility of lenders’ discrimination based on community racial characteristics, we explain why our findings should not be readily interpreted as conclusive evidence thereof. We further find that consumer’s credit history is a robust and quantitatively more important predictor of bankcard credit outcomes than racial composition of the consumer’s neighborhood, and that the consumer’s location vis-à-vis a reservation exhibits no effect on bankcard credit outcomes
AMI-LA radio continuum observations of Spitzer c2d small clouds and cores: Serpens region
We present deep radio continuum observations of the cores identified as
deeply embedded young stellar objects in the Serpens molecular cloud by the
Spitzer c2d programme at a wavelength of 1.8cm with the Arcminute Microkelvin
Imager Large Array (AMI-LA). These observations have a resolution of ~30arcsec
and an average sensitivity of 19microJy/beam. The targets are predominantly
Class I sources, and we find the detection rate for Class I objects in this
sample to be low (18%) compared to that of Class 0 objects (67%), consistent
with previous works. For detected objects we examine correlations of radio
luminosity with bolometric luminosity and envelope mass and find that these
data support correlations found by previous samples, but do not show any
indiction of the evolutionary divide hinted at by similar data from the Perseus
molecular cloud when comparing radio luminosity with envelope mass. We conclude
that envelope mass provides a better indicator for radio luminosity than
bolometric luminosity, based on the distribution of deviations from the two
correlations. Combining these new data with archival 3.6cm flux densities we
also examine the spectral indices of these objects and find an average spectral
index of 0.53+/-1.14, consistent with the canonical value for a partially
optically thick spherical or collimated stellar wind. However, we caution that
possible inter-epoch variability limits the usefulness of this value, and such
variability is supported by our identification of a possible flare in the radio
history of Serpens SMM 1.Comment: accepted MNRA
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