299 research outputs found
The Challenge of Integrating Faith-Learning-Living in Teacher Education
Teacher educators from member institutions of the Coalition for Christian Colleges and Universities are currently challenged in an unprecedented way. The challenge is to satisfy increasingly rigorous state and national teacher education standards and to fulfill the commonly held mission of Coalition institutions to integrate faith-learning-living. The research presented in this article traces the long history of integration and presents various theoretical integration models commonly supported by educators at Christian colleges and universities. This article suggests meeting the challenge in part through an original six component integration model with potential value for Christian educators representing various academic disciplines
β-amyloid in Alzheimer’s disease initiation and phenotypic diversity
Alzheimer’s disease (AD) is a progressive neurodegenerative condition characterized by behavioral changes and memory impairments, predominantly observed in the elderly population. As the most common form of dementia worldwide, AD has a large socioeconomic burden that is expected to grow in the next decades, given that no potent therapeutic strategy exists to treat the increasing population of aged individuals. The deposition of misfolded β-amyloid (Aβ) within extracellular senile plaques is a pathological hallmark of disease. The appearance of Aβ plaques has been identified as one of the earliest events in AD, and the prevailing amyloid cascade hypothesis suggests that the abnormal cleavage and misfolding of Aβ is the trigger of disease. The focus on misfolded Aβ as a central agent in AD has drawn parallels to the infectious prion protein and the protein-only hypothesis of disease transmission for prion disease. A number of studies have demonstrated that Aβ assembles into amyloid fibrils and that misfolded species can seed the aggregation of monomeric Aβ both in vitro and in vivo. Although the seeding properties of aggregated Aβ are robust, a more recent line of investigation aimed to characterize how variations in Aβ aggregate assembly influence the potency of seeding and also the progression of disease. In this doctoral dissertation, the structural features of amyloid plaque cores within a diverse cohort of 40 patients, with either sporadic or familial AD, were assessed using a unique class of conformation sensitive amyloid binding dyes referred to as luminescent conjugated oligothiophenes or LCOs. The fluorescence spectral signature of LCO stained plaque cores was strikingly different between familial AD and sporadic AD, and subtle differences were also identified between the typical and posterior cortical atrophy variants of sporadic AD. This demonstrates that the amyloid structure is distinct between AD subtypes, an observation not explained by Aβ biochemical features or clinical data. Surprisingly, within a single AD brain, multiple spectral signatures for amyloid were present and are referred to as clouds of conformational Aβ variants. The structural features of human AD-derived Aβ aggregates were also preserved upon transmission to human APP transgenic mice. The direct analysis of Aβ conformations within post-mortem human tissue provided insight into the spectrum of species present within a brain, but the presence of such Aβ variation at earlier stages of disease is unknown. In a second study, the change in conformational and biological Aβ features with aging was studied in APP transgenic mouse models with either slow or rapid cerebral β-amyloidosis. Both histological and biochemical levels of Aβ increased with aging, but the ratio of specific Aβ species, namely Aβ42/40, surprisingly peaked at the early stage of plaque appearance in the two models. An in vivo bioassay was then used to show that different aged brain extracts had increasing seeding activities, or seeding dosages (SD50), that plateaued with advanced age when injected into a transgenic host. Interestingly, when seeding activity was normalized to the amount of Aβ within the extracts, a peak in specific activity became apparent at the age when Aβ deposition first appears and Aβ42/40 was highest. This study provides further evidence that treatment of AD should be initiated early, i.e. at the time point when these potent seeds are present and before a cascade of neurodegeneration can occur. Finally, in a third study, a novel methodology capable of investigating various native Aβ assemblies in the brain was described. Here, the use of agarose electrophoresis facilitated the separation of Aβ aggregation states by size, and demonstrated that transgenic mouse brain extracts harbor Aβ aggregates with a different size distribution than in vitro Aβ fibrils. Agarose fractions were collected and enzymatically digested to produce a liquid sample, which could be used for further analysis. Immunoprecipitation with an amyloid-conformation-specific antibody confirmed that Aβ migrating with a high molecular weight had a preserved quaternary structure after the enrichment protocol. Further evidence that the structure was preserved was demonstrated when a high molecular weight fraction induced Aβ deposition when injected into transgenic mice. This novel tool provides the opportunity to screen potential therapeutic antibodies or compounds against native in vivo aggregates, while generating samples that can be further analyzed to determine the relationship between aggregate size and structure with biological features such as seeding activity. The original research within this dissertation has provided a significant contribution to the knowledge of Aβ structural features within AD, and the seeding properties over the course of disease. Additionally, the establishment of a new method for isolating in vivo seeds using agarose fractionation will allow for further basic investigations of these findings and aid in the development of novel therapeutics. Specifically targeting the earliest generated seeds within an AD subtype using immunotherapies could enhance the removal of pathogenic Aβ and provide a viable strategy to prevent AD
Reducing Bacterial Contamination in Fuel Ethanol Fermentations by Ozone Treatment of Uncooked Corn Mash
Ozonation of uncooked corn mash from the POET BPX process was investigated as a potential disinfection method for reducing bacterial contamination prior to ethanol fermentation. Corn mash (200 g) was prepared from POET ground corn and POET corn slurry and was ozonated in 250 mL polypropylene bottles. Lactic and acetic acid levels were monitored daily during the fermentation of ozonated, aerated, and nontreated corn mash samples to evaluate bacterial activity. Glycerol and ethanol contents of fermentation samples were checked daily to assess yeast activity. No yeast supplementation, no addition of other antimicrobial agents (such as antibiotics), and spiking with a common lactic acid bacterium found in corn ethanol plants,Lactobacillus plantarum, amplified the treatment effects. The laboratory-scale ozone dosages ranged from 26–188 mg/L, with very low estimated costs of 0.21–1.6/m3) of ethanol. Ozonation was found to decrease the initial pH of ground corn mash samples, which could reduce the sulfuric acid required to adjust the pH prior to ethanol fermentation. Lactic and acetic acid levels tended to be lower for samples subjected to increasing ozone dosages, indicating less bacterial activity. The lower ozone dosages in the range applied achieved higher ethanol yields. Preliminary experiments on ozonating POET corn slurry at low ozone dosages were not as effective as using POET ground corn, possibly because corn slurry samples contained recycled antimicrobials from the backset. The data suggest additional dissolved and suspended organic materials from the backset consumed the ozone or shielded the bacteria
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A conserved morphogenetic mechanism for epidermal ensheathment of nociceptive sensory neurites.
Interactions between epithelial cells and neurons influence a range of sensory modalities including taste, touch, and smell. Vertebrate and invertebrate epidermal cells ensheath peripheral arbors of somatosensory neurons, including nociceptors, yet the developmental origins and functional roles of this ensheathment are largely unknown. Here, we describe an evolutionarily conserved morphogenetic mechanism for epidermal ensheathment of somatosensory neurites. We found that somatosensory neurons in Drosophila and zebrafish induce formation of epidermal sheaths, which wrap neurites of different types of neurons to different extents. Neurites induce formation of plasma membrane phosphatidylinositol 4,5-bisphosphate microdomains at nascent sheaths, followed by a filamentous actin network, and recruitment of junctional proteins that likely form autotypic junctions to seal sheaths. Finally, blocking epidermal sheath formation destabilized dendrite branches and reduced nociceptive sensitivity in Drosophila. Epidermal somatosensory neurite ensheathment is thus a deeply conserved cellular process that contributes to the morphogenesis and function of nociceptive sensory neurons
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Scientific review by the marine science advisory panel of Oregon University System scientists of the US Commission on ocean policy preliminary report for Governor Kulongoski's Oregon response
The U.S. Commission on Ocean Policy (USCOP) has articulated a set of overarching Guiding Principles to frame the creation of a new national ocean policy. When taken collectively, these principles provide a careful, circumspect, and ambitious context from which to develop policies that will promote vibrant coastal communities, healthy and resilient ecosystems, abundant wildlife, sustainable fisheries, clean and safe shorelines, and enjoyable and inspirational recreational opportunities—in short, the visions that Oregonians articulate for their coast and ocean. The Guiding Principles align closely with Oregon’s Statewide Planning Goals, policies, and values. In fact, they underscore the importance of weighing long-term interests more heavily than short-term ones in the balance of competing uses. They are holistic in geographic scope, rather than focused on a single component of a complex ecosystem. The USCOP Guiding Principles were conceived to foster an atmosphere of objective scientific inquiry to form the basis of policy and decision-making to reconcile the diverse needs of all Oregonians.Keywords: Estuary,
Shellfish,
Beach,
Fish,
Kelp,
Estuarine,
Habitat,
Algae,
Marine,
Indicators,
Freshwater,
Mammal
Advancing the Scientific Frontier with Increasingly Autonomous Systems
A close partnership between people and partially autonomous machines has
enabled decades of space exploration. But to further expand our horizons, our
systems must become more capable. Increasing the nature and degree of autonomy
- allowing our systems to make and act on their own decisions as directed by
mission teams - enables new science capabilities and enhances science return.
The 2011 Planetary Science Decadal Survey (PSDS) and on-going pre-Decadal
mission studies have identified increased autonomy as a core technology
required for future missions. However, even as scientific discovery has
necessitated the development of autonomous systems and past flight
demonstrations have been successful, institutional barriers have limited its
maturation and infusion on existing planetary missions. Consequently, the
authors and endorsers of this paper recommend that new programmatic pathways be
developed to infuse autonomy, infrastructure for support autonomous systems be
invested in, new practices be adopted, and the cost-saving value of autonomy
for operations be studied.Comment: 10 pages (compared to 8 submitted to PSADS), 2 figures, submitted to
National Academy of Sciences Planetary Science and Astrobiology Decadal
Survey 2023-203
- …