560 research outputs found
A tabulation of pipe length to diameter ratios as a function of Mach number and pressure ratios for compressible flow
Computer programs and resulting tabulations are presented of pipeline length-to-diameter ratios as a function of Mach number and pressure ratios for compressible flow. The tabulations are applicable to air, nitrogen, oxygen, and hydrogen for compressible isothermal flow with friction and compressible adiabatic flow with friction. Also included are equations for the determination of weight flow. The tabulations presented cover a wider range of Mach numbers for choked, adiabatic flow than available from commonly used engineering literature. Additional information presented, but which is not available from this literature, is unchoked, adiabatic flow over a wide range of Mach numbers, and choked and unchoked, isothermal flow for a wide range of Mach numbers
THE ECONOMIC IMPACTS OF A FOOT-AND-MOUTH DISEASE OUTBREAK: A REGIONAL ANALYSIS
Contagious animal diseases like foot-and-mouth disease (FMD) are often referred to as economic diseases because of the magnitude of economic harm they can cause to producers and to local communities. This study demonstrates the local economic impact of a hypothetical FMD outbreak in southwest Kansas, an area with high density of cattle feeding. The expected (most probable) economic impact of the disease hinges heavily on where the incidence of the disease occurs. If the disease were to occur in a cow-calf herd in the region economic impact is expected to be relatively small compared to if it were introduced simultaneously in five large feedlots in southwest Kansas. Disease surveillance, management strategies, mitigation investment, and overall diligence clearly need to be much greater in concentrated cattle feeding and processing areas at the large feeding operations in the region.Livestock Production/Industries,
O True Apothecary: How Forensic Science Helps Solve a Classic Crime
As part of a university-wide project to explore Shakespeare’s classic play, Romeo and Juliet, from a variety of perspectives, an interdisciplinary talk was presented to the university community on the chemistry of the potions and poisons referenced in Romeo and Juliet. To draw the multidisciplinary audience in and to teach about forensics as well as pharmaceutical herbs and chemicals, the presentation was given from the perspective of how a modern crime scene investigator would approach the famous play’s final death scene without any prior knowledge of the situation. An autopsy of Juliet’s body might have revealed the presence of the chemicals, hyoscine and atropine, that come from the plant Atropa belladonna. The autopsy could reveal whether the Friar had set out to sedate Juliet or if he had attempted to kill her. An autopsy of Romeo’s body might have revealed the presence of aconitine from the plant Aconitum napellus. Using a classic story to teach about chemistry, basic ideas were introduced about forensics and pharmacology, emphasizing the importance of dose when determining the effect of a drug on the human body
BASE (Broadening Access to Science Education) Camp for Young Women
This poster will describe the development and implementation of an annual two-week residential summer science enrichment program for 24 rising female juniors and seniors from Bridgeport, CT, a community comprised of many health disparity populations traditionally underrepresented in science. The program, entitled BASE (Broadening Access to Science Education), has an overall goal to excite and inform students from local health disparity populations about the process and promise of science in an effort to increase interest in the pursuit of STEM and health careers after college. The program includes three key components. The first component is the Research Immersion Experience, a weeklong scientific research experience that engages students in faculty-led research projects. The second component of the camp is the Science and Health Careers Exploration that exposes students to various careers in science, technology, and health sciences and the academic paths required to get there. The final component of the program is the College Admissions Counseling in which the Fairfield University Office of Undergraduate Admissions educates the students about the process and requirements for admission to college, informs students about financial aid opportunities, and engages students in mock interviews and essay writing. We will present pre- and post-camp participant, and post-camp counselor, and faculty survey results from 2012. Camper feedback is overwhelmingly positive, and the program appears to be meeting its goals to excite and inform students from health disparity populations about science and to inspire them to pursue scientific careers
BASE (Broadening Access to Science Education): A Research and Mentoring Focused Summer STEM Camp Serving Underrepresented High School Girls
BASE (Broadening Access to Science Education) Camp is a hands-on two-week residential summer science experience on the Fairfield University campus, in Fairfield CT, USA. The annual program targets 24 young women who attend high school in our neighboring city of Bridgeport, CT, the most economically depressed city in CT. The camp, which is free to students, includes three components. The first is the week-long Research Immersion Experience, which engages students in faculty-mentored science research projects assisted by current undergraduate STEM majors. The second component is Career Exploration, which allows students to explore a variety of careers in science, technology, and healthcare, as well as the academic paths required to get there. The third component is College Admissions Counseling, which links campers with Fairfield University’s undergraduate admissions staff for mentoring on the college application process. This program is particularly unique in that it rests entirely on a female staff, engaging Fairfield University’s women STEM faculty and undergraduate STEM majors. BASE Camp was founded and developed through funding from several organizations, and is currently supported by a five-year R25 grant from the NIMHD (National Institute on Minority Health and Health Disparities), National Institutes of Health. After four years in this format, the program has engaged close to 100 young women. Data collected show nearly 100% camper satisfaction with the program. In addition, we found the camp increased camper perception of their science knowledge and confidence, as well as understanding of skills required to succeed in careers in science and health. Finally, in a follow-up survey we found that 95% have applied to, or plan to apply to, college, and 87% are interested in pursuing a STEM or health-related career. The close mentorship of these young women by female role models at the faculty and undergraduate levels has greatly contributed to the success and efficacy of this experience. We hope our program can be used as a model for others to create programming in an effort to promote and support underrepresented women in the pursuit of STEM careers
Density functional study of the adsorption of K on the Ag(111) surface
Full-potential gradient corrected density functional calculations of the
adsorption of potassium on the Ag(111) surface have been performed. The
considered structures are Ag(111) (root 3 x root 3) R30degree-K and Ag(111) (2
x 2)-K. For the lower coverage, fcc, hcp and bridge site; and for the higher
coverage all considered sites are practically degenerate.
Substrate rumpling is most important for the top adsorption site. The bond
length is found to be nearly identical for the two coverages, in agreement with
recent experiments. Results from Mulliken populations, bond lengths, core level
shifts and work functions consistently indicate a small charge transfer from
the potassium atom to the substrate, which is slightly larger for the lower
coverage.Comment: to appear in Phys Rev
Antimicrobial Activity in the Pallial Cavity Fluids of the Oyster Crassostrea virginica (Gmelin) from a Highly Impacted Harbor in Western Long Island Sound
Fluid and its associatedmucus from the pallial (mantle) cavity of eastern oysters Crassostrea virginica (Gmelin) from Black RockHarbor, Bridgeport, Connecticut, inhibited growth of both Gram-positive (Bacillus subtilis, Staphylococcus aureus) and Gram-negative (Escherichia coli, Serratia marcescens, and Vibrio parahaemolyticus) bacteria in antimicrobial assays. In the presence of oyster fluid, E. coli resulted in significant reduction in growth after 26 h. Soluble lysozyme activity in pallial cavity fluid of oysters collected in the fall was 3 times greater than that measured in combined winter—spring—summer samples (P = 0.0008). During the course of the study, copper concentrations in pallial cavity fluid ranged from 0.60–2.49 ppm and zinc concentrations ranged from 9.7–61.0 ppm. Copper concentrations remained relatively constant throughout the study; the highest zinc concentrations were recorded in the fall. Fall antimicrobial assays showed heightened antimicrobial activity compared with the spring, which may be the result of increased lysozyme activity and higher zinc concentrations present in the pallial cavity fluid at that time of year. Results of this study suggest that pallial cavity fluid and its associated mucus likely serve an important role in defense-related functions as the first line of defense against infections from environmental pathogens in Crassostrea virginica
Parallel variation of mass transport and heterogeneous and homogeneous electron transfer rates in hybrid redox polyether molten salts
Metal complexes can be prepared as highly viscous (semisolid), room temperature molten salts by combining them with oligomeric polyether substituents. The fluidity and transport properties of these hybrid redox polyether melts can be systematically manipulated by changing the oligomeric chain lengths and by adding unattached oligomers as plasticizers. This paper describes the voltammetrically measured transport properties of several Co(II) polypyridine (2,2‘-bipyridine, phenanthroline) melts. The properties evaluated are the physical self-diffusion coefficient (DPHYS) of the cationic complex in its melt, the diffusivity of its counterion (DCION), the heterogeneous electron-transfer rate constant (kHET) of the Co(III/II) oxidation at the electrode surface, and the rate constant (kEX) for homogeneous electron self-exchange between Co(II) and Co(I) in the mixed valent layer next to the electrode. These dynamics parameters change in parallel manners, over a large (\u3e103) range of values, when the melt fluidity is changed by plasticizers or temperature. While kHET and kEX both change systematically with DPHYS, they change on a more nearly proportional basis with DCION. The latter relationship is interpreted as a kind of solvent dynamics control in which both the homogeneous Co(II/I) and heterogeneous Co(III/II) reaction rates are controlled by the ionic atmosphere relaxation time constant, namely, the time constant of redistribution of counterions following an electron-transfer step that has produced a nonequilibrium charge distribution. DCION provides a measure of the ion atmosphere relaxation rate
Research shapes policy: but the dynamics are subtle
Major policy initiatives such as the Quality and Outcomes Framework (QOF) in the national contract for UK general practitioners might variably be informed by evidence at their inception, implementation and subsequent evolution. But what evidence gets admitted into these policy debates—and what is left out? Using QOF as an example, this article demonstrates what an analysis of the relationship between policy and the associated research can tell us about the underlying policy assumptions and about the role of evidence in policy debates
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