300 research outputs found
Separation of the n-Sphere by an (n - 1)-Sphere
In this thesis we consider certain (n-1)-spheres embedded in S^n (we will frequently use the fact that S^n is topologically equivalent to the one point compactification of E^n). The problem is then to establish the existence or non-existence of certain topological properties of the two domains into which S^n is separated by the given (n-1)-spheres
The Lunar Orbital Prospector
The establishment of lunar bases will not end the need for remote sensing of the lunar surface by orbiting platforms. Human and robotic surface exploration will necessarily be limited to some proximate distance from the support base. Near real-time, high-resolution, global characterization of the lunar surface by orbiting sensing systems will continue to be essential to the understanding of the Moon's geophysical structure and the location of exploitable minerals and deposits of raw materials. The Lunar Orbital Prospector (LOP) is an orbiting sensing platform capable of supporting a variety of modular sensing packages. Serviced by a lunar-based shuttle, the LOP will permit the exchange of instrument packages to meet evolving mission needs. The ability to recover, modify, and rotate sensing packages allows their reuse in varying combinations. Combining this flexibility with robust orbit modification capabilities and near real-time telemetry links provides considerable system responsiveness. Maintenance and modification of the LOP orbit are accomplished through use of an onboard propulsion system that burns lunar-supplied oxygen and aluminum. The relatively low performance of such a system is more than compensated for by the elimination of the need for Earth-supplied propellants. The LOP concept envisions a continuous expansion of capability through the incorporation of new instrument technologies and the addition of platforms
Application of Raman Spectroscopy to Small Satellites in Exploring Solar Bodies
Raman Spectroscopy is an active remote sensing method that can map planetary mineral and chemical abundances and their distributions. Raman spectroscopy can also be used to study the chemical composition of various planetary atmospheres. The remote raman technique utilizes a low power laser to stimulate raman scattering at the substance and a spectrometer receives the returned raman spectrum at the spacecraft. The returned spectrum contains the shifts in frequency, shifted from that of the incident laser light, that are characteristic of the substance. The intensity of the raman spectrum lines is proportional to the amount of the substance present. Thus, with raman spectral information, the identification of a substance and an estimate of its volumetric concentrations can be achieved. The baseline remote raman instrument system utilizes a 10 W krypton laser and a RIRIS spectrally sensitive detector array, cassegran optics, has a mass of 200 Kg, and consumes 1 KW of electrical power. This paper explores the basic concepts of remote raman spectroscopy and postulates an instrument package that is compatible with the mass and size constraints of a small satellite. Various solar system exploratory missions using raman spectroscopy are discussed including the study of the surface of the moon, Earth\u27s upper atmosphere, the atmosphere of Mars, the atmosphere of Jupiter, and the rings of Saturn
Changes in Cultural Practices of Farmers in Southeast Nebraska as a Result of Their Adoption of Transgenic Crops
How do cultural practices change as producers adopt transgenic crops? A group of progressive producers in southeast Nebraska were surveyed to learn how practices changed as RR soybeans were adopted. These producers were found conservative in changing their management practices to use transgenic crops most efficiently. Tillage and planting practices were unchanged from conventional crops. Seed dealers and on-farm research were the top educational resources used in determining which varieties of soybeans to plant. Based on this study, on-farm research offers Extension an avenue for providing needed information to producers
Influence of Postpartum Nutrition on Cow Weight and Condition Change, Estrus, Conception Rate, and Calf Performance of Fallcalving Beef Cows
This study is concerned with the effect that different levels of postpartum nutrition has on reproductive performance of fall-calving beef cows. The primary objective is to determine how nutritional regimes resulting in different weight loss patterns affects return to estrus, conception rate, and calf performance in beef cows calving from September through November.Animal Scienc
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Causticizing for Black Liquor Gasifiers
The cost-benefit outlook of black liquor gasification (BLG) could be greatly improved if the smelt causticization step could be achieved in situ during the gasification step. Or, at a minimum, the increase in causticizing load associated with BLG could be mitigated. A number of chemistries have been proven successful during black liquor combustion. In this project, three in situ causticizing processes (titanate, manganate, and borate) were evaluated under conditions suitable for high temperature entrained flow BLG, and low temperature steam reforming of black liquor. The evaluation included both thermodynamic modeling and lab experimentation. Titanate and manganate were tested for complete direct causticizing (to thus eliminate the lime cycle), and borates were evaluated for partial causticizing (to mitigate the load increase associated with BLG). Criteria included high carbonate conversion, corresponding hydroxide recovery upon hydrolysis, non process element (NPE) removal, and economics. Of the six cases (three chemistries at two BLG conditions), only two were found to be industrially viable: titanates for complete causticizing during high temperature BLG, and borates for partial causticizing during high temperature BLG. These two cases were evaluated for integration into a gasification-based recovery island. The Larsen [28] BLG cost-benefit study was used as a reference case for economic forecasting (i.e. a 1500 tpd pulp mill using BLG and upgrading the lime cycle). By comparison, using the titanate direct causticizing process yielded a net present value (NPV) of 16M
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Impact of Tobacco-Related Health Warning Labels across Socioeconomic, Race and Ethnic Groups: Results from a Randomized Web-Based Experiment
Background: The U.S. Family Smoking Prevention and Tobacco Control Act of 2009 requires updating of the existing text-only health warning labels on tobacco packaging with nine new warning statements accompanied by pictorial images. Survey and experimental research in the U.S. and other countries supports the effectiveness of pictorial health warning labels compared with text-only warnings for informing smokers about the risks of smoking and encouraging cessation. Yet very little research has examined differences in reactions to warning labels by race/ethnicity, education or income despite evidence that population subgroups may differ in their ability to process health information. The purpose of the present study was to evaluate the potential impact of pictorial warning labels compared with text-only labels among U.S. adult smokers from diverse racial/ethnic and socioeconomic subgroups. Methods/Findings: Participants were adult smokers recruited from two online research panels (n = 3,371) into a web-based experimental study to view either the new pictorial warnings or text-only warnings. Participants viewed the labels and reported their reactions. Adjusted regression models demonstrated significantly stronger reactions for the pictorial condition for each outcome salience (b = 0.62, p<.001); perceived impact (b = 0.44, p<.001); credibility (OR = 1.41, 95% CI = 1.22โ1.62), and intention to quit (OR = 1.30, 95% CI = 1.10โ1.53). No significant results were found for interactions between condition and race/ethnicity, education, or income. The only exception concerned the intention to quit outcome, where the condition-by-education interaction was nearly significant (p = 0.057). Conclusions: Findings suggest that the greater impact of the pictorial warning label compared to the text-only warning is consistent across diverse racial/ethnic and socioeconomic populations. Given their great reach, pictorial health warning labels may be one of the few tobacco control policies that have the potential to reduce communication inequalities across groups. Policies that establish strong pictorial warning labels on tobacco packaging may be instrumental in reducing the toll of the tobacco epidemic, particularly within vulnerable communities
Infliximab, adalimumab and golimumab for treating moderately to severely active ulcerative colitis after the failure of conventional therapy (including a review of TA140 and TA262): clinical effectiveness systematic review and economic model.
BACKGROUND: Ulcerative colitis (UC) is the most common form of inflammatory bowel disease in the UK. UC can have a considerable impact on patients' quality of life. The burden for the NHS is substantial. OBJECTIVES: To evaluate the clinical effectiveness and safety of interventions, to evaluate the incremental cost-effectiveness of all interventions and comparators (including medical and surgical options), to estimate the expected net budget impact of each intervention, and to identify key research priorities. DATA SOURCES: Peer-reviewed publications, European Public Assessment Reports and manufacturers' submissions. The following databases were searched from inception to December 2013 for clinical effectiveness searches and from inception to January 2014 for cost-effectiveness searches for published and unpublished research evidence: MEDLINE, EMBASE, Cumulative Index to Nursing and Allied Health Literature, The Cochrane Library including the Cochrane Systematic Reviews Database, Cochrane Controlled Trials Register, Database of Abstracts of Reviews of Effects, the Health Technology Assessment database and NHS Economic Evaluation Database; ISI Web of Science, including Science Citation Index, and the Conference Proceedings Citation Index-Science and Bioscience Information Service Previews. The US Food and Drug Administration website and the European Medicines Agency website were also searched, as were research registers, conference proceedings and key journals. REVIEW METHODS: A systematic review [including network meta-analysis (NMA)] was conducted to evaluate the clinical effectiveness and safety of named interventions. The health economic analysis included a review of published economic evaluations and the development of a de novo model. RESULTS: Ten randomised controlled trials were included in the systematic review. The trials suggest that adult patients receiving infliximab (IFX) [Remicade(ยฎ), Merck Sharp & Dohme Ltd (MSD)], adalimumab (ADA) (Humira(ยฎ), AbbVie) or golimumab (GOL) (Simponi(ยฎ), MSD) were more likely to achieve clinical response and remission than those receiving placebo (PBO). Hospitalisation data were limited, but suggested more favourable outcomes for ADA- and IFX-treated patients. Data on the use of surgical intervention were sparse, with a potential benefit for intervention-treated patients. Data were available from one trial to support the use of IFX in paediatric patients. Safety issues identified included serious infections, malignancies and administration site reactions. Based on the NMA, in the induction phase, all biological treatments were associated with statistically significant beneficial effects relative to PBO, with the greatest effect associated with IFX. For patients in response following induction, all treatments except ADA and GOL 100โmg at 32-52 weeks were associated with beneficial effects when compared with PBO, although these were not significant. The greatest effects at 8-32 and 32-52 weeks were associated with 100โmg of GOL and 5โmg/kg of IFX, respectively. For patients in remission following induction, all treatments except ADA at 8-32 weeks and GOL 50โmg at 32-52 weeks were associated with beneficial effects when compared with PBO, although only the effect of ADA at 32-52 weeks was significant. The greatest effects were associated with GOL (at 8-32 weeks) and ADA (at 32-52 weeks). The economic analysis suggests that colectomy is expected to dominate drug therapies, but for some patients, colectomy may not be considered acceptable. In circumstances in which only drug options are considered, IFX and GOL are expected to be ruled out because of dominance, while the incremental cost-effectiveness ratio for ADA versus conventional treatment is approximately ยฃ50,300 per QALY gained. LIMITATIONS: The health economic model is subject to several limitations: uncertainty associated with extrapolating trial data over a lifetime horizon, the model does not consider explicit sequential pathways of non-biological treatments, and evidence relating to complications of colectomy was identified through consideration of approaches used within previous models rather than a full systematic review. CONCLUSIONS: Adult patients receiving IFX, ADA or GOL were more likely to achieve clinical response and remission than those receiving PBO. Further data are required to conclusively demonstrate the effect of interventions on hospitalisation and surgical outcomes. The economic analysis indicates that colectomy is expected to dominate medical treatments for moderate to severe UC. STUDY REGISTRATION: This study is registered as PROSPERO CRD42013006883. FUNDING: The National Institute for Health Research Health Technology Assessment programme
Long-Term Maintenance of Psoriatic Human Skin on Congenitally Athymic (Nude) Mice
Transplantation of involved psoriatic and nonpsoriatic human skin onto congenitally athymie (nude) mice has been performed successfully. Although biopsies at selected intervals demonstrate that the excess glycogen deposition normally seen in psoriasis is no longer consistently present, the psoriatic grafts did retain the usual characteristic histologic differences throughout the life of the animal, up to 11 weeks. This grafting procedure potentially represents a useful method whereby the study of psoriasis can be made in a nonhuman, living system
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