2,726 research outputs found
A methodology for evaluating the implications of climate change on the design and performance of flexible pavements
A methodology is presented by which the implications of climate change on pavement deterioration can be assessed. This work focuses on the preparation and use of climate model datasets as inputs into the Mechanistic-Empirical Pavement Design Guide model to simulate pavement performance and deterioration over time. The methodology is illustrated using climate model temperature data from three North American Regional Climate Change Assessment Program scenarios at four sites across New England for alligator cracking and asphalt concrete rutting. The change in alligator cracking was shown to be negligible, while the difference in rutting was up to 31% between future and hindcast model periods; it suggests that climate change needs to be considered for pavement design and management. Additional work needs to be done using the proposed methodology in converting and running the remaining deterioration relevant variables in model scenarios to fully assess the implications of climate change on pavement deterioration
Investigating Chemotherapeutic Resistance: Why is Glioblastoma So Deadly?
Glioblastoma multiforme (GBM), a malignancy of the glioblast stem cells of the brain, is one of the most aggressive and untreated forms of brain cancer. When an individual is diagnosed with GBM, depending on the location of the tumor, there are three treatment options including surgery, radiation, chemotherapy or the combination of these treatments. Many patients choose chemotherapy, however most GBM cases show little to no response to Temozolomide (TMZ), which is a common chemotherapy drug used for this type of cancer. In some recent studies, researchers have noticed an elevated amount or over production of an enzyme, Inosine 5\u27-monophosphate dehydrogenase (IMPDH). This enzyme 31 helps with DNA repair but in many GBM cases, due to its over production, it repairs at such a fast rate it does not allow TMZ to terminate the cancerous tumors. In our research we have been investigating whether the chemotherapeutic agent causes the increase in expression directly or whether it is a unique property of this cell type. Future directions involve: determining a molecular pathway that could lead to IMPDH expression at such high levels under chemotherapeutic stress and whether co-administering IMPDH inhibitors with TMZ can improve prognosis for those suffering from GBM.https://openriver.winona.edu/urc2019/1023/thumbnail.jp
Finding middle ground between intellectual arrogance and intellectual servility: Development and assessment of the limitations-owning intellectual humility scale
Recent scholarship in intellectual humility (IH) has attempted to provide deeper understanding of the virtue as personality trait and its impact on an individual's thoughts, beliefs, and actions. A limitations-owning perspective of IH focuses on a proper recognition of the impact of intellectual limitations and a motivation to overcome them, placing it as the mean between intellectual arrogance and intellectual servility. We developed the Limitations-Owning Intellectual Humility Scale to assess this conception of IH with related personality constructs. In Studies 1 (n= 386) and 2 (n = 296), principal factor and confirmatory factor analyses revealed a three-factor model – owning one's intellectual limitations, appropriate discomfort with intellectual limitations, and love of learning. Study 3 (n = 322) demonstrated strong test-retest reliability of the measure over 5 months, while Study 4 (n = 612) revealed limitations-owning IH correlated negatively with dogmatism, closed-mindedness, and hubristic pride and positively with openness, assertiveness, authentic pride. It also predicted openness and closed-mindedness over and above education, social desirability, and other measures of IH. The limitations-owning understanding of IH and scale allow for a more nuanced, spectrum interpretation and measurement of the virtue, which directs future study inside and outside of psychology
Better, Faster, Stronger: Integrating Archives Processing and Technical Services
The University of Denver’s Penrose Library implemented a consolidated cataloging and archives processing unit for all materials, taking advantage of the structure, workflow design, and staff resources that were already in place for library-wide materials processing: acquisitions, cataloging, binding, and stacks maintenance. The objective of Penrose Library’s integrated approach was to efficiently create metadata that allow searches based on subject relevance rather than on collection provenance. The library streamlined archives processing by integrating digital content creation and management into the materials processing workflow. The result is a flexible, sustainable, and scalable model for archives processing that utilizes existing staff by enhancing and extending the skills of both experienced monographs catalogers and archivists
Nuclear actin-related proteins at the core of epigenetic control
Nuclear Actin-Related Proteins (ARPs) and actin combine as heterodimers to bind a large helicase subunit and form a core complex essential to the assembly and function of most chromatin remodeling and modifying machines. They are the most common shared subunits of these large and diverse assemblies in eukaryotes. We recently argued that most nuclear ARPs evolved directly from actin prior to the divergence of the eukaryotic kingdoms and did not evolve from pre-existing ARPs.2 Arabidopsis plants defective in nuclear ARP4, ARP5, ARP6 or ARP7 have extreme developmental phenotypes. Our recent publication demonstrates that ARP5-defective plants are not only dwarfed and have aberrant cell sizes, but are also hypersensitive to mutagenic agents that cause double strand DNA breaks.5 In Smith et al.6 we show that ARP6-defective plants, in addition to their extreme developmental phenotypes like small organs and early flowering, present an apparent Phosphate Starvation Response with strong morphological and molecular phenotypes. Herein, we interpret our latest data in the light of a hypothesis stating that in addition to their roles in overcoming DNA compaction that affects basal gene expression and silencing, nuclear ARP-containing chromatin complexes exert primary epigenetic control over high-level regulatory factors. © 2010 Landes Bioscience
Hijacking membrane transporters for arsenic phytoextraction
Arsenic is a toxic metalloid and recognized carcinogen. Arsenate and arsenite are the most common arsenic species available for uptake by plants. As an inorganic phosphate (Pi) analog, arsenate is acquired by plant roots through endogenous Pi transport systems. Inside the cell, arsenate is reduced to the thiol-reactive form arsenite. Glutathione (GSH)-conjugates of arsenite may be extruded from the cell or sequestered in vacuoles by members of the ATP-binding cassette (ABC) family of transporters. In the present study we sought to enhance both plant arsenic uptake through Pi transporter overexpression, and plant arsenic tolerance through ABC transporter overexpression. We demonstrate that Arabidopsis thaliana plants overexpressing the high-affinity Pi transporter family members, AtPht1;1 or AtPht1;7, are hypersensitive to arsenate due to increased arsenate uptake. These plants do not exhibit increased sensitivity to arsenite. Co-overexpression of the yeast ABC transporter YCF1 in combination with AtPht1;1 or AtPht1;7 suppresses the arsenate-sensitive phenotype while further enhancing arsenic uptake. Taken together, our results support an arsenic transport mechanism in which arsenate uptake is increased through Pi transporter overexpression, and arsenic tolerance is enhanced through YCF1-mediated vacuolar sequestration. This work substantiates the viability of coupling enhanced uptake and vacuolar sequestration as a means for developing a prototypical engineered arsenic hyperaccumulator. © 2012 Elsevier B.V
Phase Transition Study of Superconducting Microstructures
The presented results are part of a feasibility study of superheated
superconducting microstructure detectors. The microstructures (dots) were
fabricated using thin film patterning techniques with diameters ranging from
m up to m and thickness of m. We used arrays and single
dots to study the dynamics of the superheating and supercooling phase
transitions in a magnetic field parallel to the dot surface. The phase transi-
tions were produced by either varying the applied magnetic field strength at a
constant temperature or changing the bath temperature at a constant field.
Preliminary results on the dynamics of the phase transitions of arrays and
single indium dots will be reported.Comment: 7pages in LaTex format, five figures available upon request by
[email protected], preprint Bu-He 93/
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