6,353 research outputs found
[NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 2:] External Information Sources and aerospace R&D: The use and importance of technical reports by US aerospace engineers and scientists
This paper formulates and studies two propositions. Proposition 1 states that information that is external to the aerospace organization tends to be used less than internal sources of information; the more geographically removed the information is from the organization, the less likely it is to be used. Proposition 2 states that of the various sociometric variables assumed to influence the use of an information channel or source, perceived accessibility exerts the greatest influence. Preliminary analysis based on surveys supports Proposition 1. This analysis does not support Proposition 2, however. Evidence here indicates that reliability and relevance influence the use of an information source more than the idea of perceived accessibility
Autographs for Freedom and Reaching a New Abolitionist Audience
Scholars correctly appreciate Frederick Douglass’s novella The Heroic Slave (1853) as an important early work of African American literature and as a significant indicator of its author’s endorsement of violent tactics to end slavery in the United States.1 This essay will literally step back farther from the text of Douglass’s only fictional work, and examine The Heroic Slave as a component of a larger project—the gift book Autographs for Freedom—edited by Douglass and his closest ally in the early 1850s, British abolitionist Julia Griffiths. The thirty-nine pieces of short fiction, poetry, essays, and correspondence in the 263-page anthology were envisioned as tools to construct a wider and politically more potent antislavery alliance than any in which the two abolitionists had previously participated. In the diverse composition of its collection of authors and antislavery themes, Autographs for Freedom was both a cultural and political tool designed by Douglass and Griffiths to help assemble a more powerful antislavery coalition from the volume’s reading audience
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Bachia heteropa
Number of Pages: 10Integrative BiologyGeological Science
Strengthening Community Foundations - Redefining the Opportunities
Commissioned by the Council on Foundations and released in October 2003, this white paper details the findings and the implications of our study of costs and revenues at nine community foundations. Offering a new perspective for community foundation sustainability, the white paper proposes that community foundations examine their strategy and operations on a product-by-product basis, taking into account their mission-driven priorities, internal costs, customer preferences and the competing donor alternatives for each type of product or service they offer
The Attitudes about Complex Therapy Scale (ACTS) in Type 2 Diabetes and Cardiovascular Disease: Development, Validity and Reliability
Background: Type 2 diabetes is associated with cardiovascular disease, and patients with both conditions are prescribed complex medication regimens.
Aim: The aim was to develop a reliable and valid measure of attitudes associated with the prescription and management of multiple medicines in patients with Type 2 diabetes and cardiovascular disease.
Methods: Principal component analysis (PCA) and Cronbach alpha assessed the reliability of the Attitudes about Complex Therapy Scale (ACTS). Examinations of relationships with related measures inform concurrent validity. Questionnaires were sent to a cross-sectional sample of 480 people prescribed multiple medicines for co-morbid Type 2 diabetes.
Results: Cronbach alpha was 0.76, indicating the scale had good internal reliability. PCA rotated a four factor model accounting for 37% of the variance. Four subscales identified; 1. Concerns about multiple medicines and increasing numbers of medicines; 2.Anxiety over missed medicines; 3. Desires to substitute medicines and reduce the number of medicines prescribed and; 4. Perceptions related to organising and managing complex therapy. The ACTS showed significant relationships with measures of anxiety, depression, general beliefs about medicines and self-efficacy. Also, the ACTS significantly correlated with adherence to medicines, showing good predictive validity.
Conclusion: The ACTS was designed to assess negative attitudes towards complex therapy and multiple medication management. This tool could aid prescribing decisions and may identify people who are intentionally non-adherent to all or some of their medicines
Pituitary Adenylate Cyclase-Activating Polypeptide Orchestrates Neuronal Regulation Of The Astrocytic Glutamate-Releasing Mechanism System x\u3csub\u3ec\u3c/sub\u3e\u3csup\u3e−\u3c/sup\u3e
Glutamate signaling is achieved by an elaborate network involving neurons and astrocytes. Hence, it is critical to better understand how neurons and astrocytes interact to coordinate the cellular regulation of glutamate signaling. In these studies, we used rat cortical cell cultures to examine whether neurons or releasable neuronal factors were capable of regulating system xc-(Sxc), a glutamate-releasing mechanism that is expressed primarily by astrocytes and has been shown to regulate synaptic transmission. We found that astrocytes cultured with neurons or exposed to neuronal-conditioned media displayed significantly higher levels of Sxc activity. Next, we demonstrated that the pituitary adenylate cyclase-activating polypeptide (PACAP) may be a neuronal factor capable of regulating astrocytes. In support, we found that PACAP expression was restricted to neurons, and that PACAP receptors were expressed in astro-cytes. Interestingly, blockade of PACAP receptors in cultures comprised of astrocytes and neurons significantly decreased Sxc activity to the level observed in purified astrocytes, whereas application of PACAP to purified astrocytes increased Sxc activity to the level observed in cultures comprised of neurons and astrocytes. Collectively, these data reveal that neurons coordinate the actions of glutamate-related mechanisms expressed by astrocytes, such as Sxc, a process that likely involves PACAP
Analyzing Four-Year Public University and Two-Year College Graduation Rates
This paper examines the graduation rates between 2000 and 2015 of United States colleges and universities at the national, state, and institutional levels. This research focuses on two-year and four-year programs. Rates are investigated longitudinally along with variables that distinguish between public/private institutions, percentages of full-time and part-time enrollments, a variety of completion times, and levels of academic achievement at entry that include SAT scores and high school GPAs. The paper uses a logistic growth function that has been used by other researchers to model four-, five-, and six-year graduation rates of individuals and selected cohort groups; graduation rate trajectories for students of differing academic achievement backgrounds are projected into the future to demonstrate maximum graduation rates expected for entering cohorts. Included is the analysis of national, state, and institutional graduation-rate results in four-year institutions of the 50 states; examples from 14 public colleges and universities in Indiana and several surrounding states are also considered. In addition to fitting their graduation rates to the logistic function and extracting associated growth variables, we use percentages of part-time students to predict two- and four-year graduation rates at the national, state, and institutional levels in the 50 states. The analysis examined the graduation rates between 2000 and 2015 of United States colleges and universities and showed no correlation between a state’s two-year and four-year cohort graduation rates; verified an inverse mathematical relationship between graduation rates and percentage of part-time students; confirmed that for median SAT scores of 800 or lower one expects very low on-time graduation rates
Exogenous selection shapes germination behaviour and seedling traits of populations at different altitudes in a Senecio hybrid zone
Background and Aims The Senecio hybrid zone on Mt Etna, Sicily, is characterized by steep altitudinal clines in quantitative traits and genetic variation. Such clines are thought to be maintained by a combination of ‘endogenous' selection arising from genetic incompatibilities and environment-dependent ‘exogenous' selection leading to local adaptation. Here, the hypothesis was tested that local adaptation to the altitudinal temperature gradient contributes to maintaining divergence between the parental species, S. chrysanthemifolius and S. aethnensis. Methods Intra- and inter-population crosses were performed between five populations from across the hybrid zone and the germination and early seedling growth of the progeny were assessed. Key Results Seedlings from higher-altitude populations germinated better under low temperatures (9-13 °C) than those from lower altitude populations. Seedlings from higher-altitude populations had lower survival rates under warm conditions (25/15 °C) than those from lower altitude populations, but also attained greater biomass. There was no altitudinal variation in growth or survival under cold conditions (15/5 °C). Population-level plasticity increased with altitude. Germination, growth and survival of natural hybrids and experimentally generated F1s generally exceeded the worse-performing parent. Conclusions Limited evidence was found for endogenous selection against hybrids but relatively clear evidence was found for divergence in seed and seedling traits, which is probably adaptive. The combination of low-temperature germination and faster growth in warm conditions might enable high-altitude S. aethnensis to maximize its growth during a shorter growing season, while the slower growth of S. chrysanthemifolius may be an adaptation to drought stress at low altitudes. This study indicates that temperature gradients are likely to be an important environmental factor generating and maintaining adaptive divergence across the Senecio hybrid zone on Mt Etn
Stagnate summers : climate induced changes in physical mixing parameters in Missouri reservoirs
Lakes and reservoirs are important environmental sentinels for climate change. As air temperatures rise so do the temperatures of these water bodies affecting their physical, chemical, and biological properties. Being used for drinking water supplies, fisheries, and human recreation, these long term potential changes can be an important factor for their use. Climate change has been associated with altering physical reservoir parameters, such as mixing depth, water temperatures, and water chemistry. Using a historical dataset to find both break points and monotonic trends that may indicate climate having influenced our reservoirs we found little in terms of monotonic trends. However, we did witness changes in all systems in regards to break points for almost every parameter. Our systems cannot directly correlate to having had climate change based effects, as we can neither support or refute its evidence in our reservoirs as changes relating to climate do not only impact physical parameters but also animal and plant communities, and social factors such as use (influenced by cyanobacteria blooms). It is even plausible that increased in reservoir production and turbidity could lead to shifts in physical trends that would otherwise be different in non-affected reservoirs. Over all more information is needed to create a better picture of exactly how climate change is impacting the physical mixing parameters in Missouri reservoirs as they are complex and varied systems.Cody Kimbell, John R. Jones, Daniel Obrecht, and Rebecca North (University of Missouri, Columbia
Target renal damage: the microvascular associations of increased aortic stiffness in patients with COPD
Background
Although renal impairment has been described in COPD, there is opportunity to evaluate further to determine nature and consider optimal management. Increased aortic stiffness, as seen in COPD, leads to reduced buffering of pulsatile flow. We hypothesised that urinary albumin creatinine ratio (UACR) would reflect glomerular damage related to aortic stiffness.
Methods
Patients with COPD and controls underwent spirometry, blood pressure, arterial stiffness - aortic pulse wave velocity (PWV) and provided a spot urine sample for UACR, with other renal biomarkers measured.
Results
The UACR was increased in patients (n = 52): 0.80 mg/mmol compared to controls (n = 34): 0.46 mg/mmol, p < 0.05. Aortic PWV was related to log10 UACR in all subjects (r = 0.426, p < 0.001) and COPD patients alone. Aortic PWV was a significant variable for UACR with oxygen saturations, after accounting for potential confounders. Eight subjects (7 patients) reached a defined clinical microalbuminuria threshold, with aortic PWV greater in these patients compared to those patients without, although albuminuria is a continuum. Proximal tubular damage biomarkers, unlike the glomerular marker, were not different between patients and controls.
Conclusions
There is glomerular damage in patients with COPD evidenced by increased UACR, related to increased aortic stiffness. Besides the macrovascular prognostic implications of increased aortic stiffness, the microvascular state in COPD management should be considered
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