2,278 research outputs found
Transonic flow in a converging-diverging nozzle Final report
Transonic equations of motion for convergent-divergent nozzl
Engineering and programming manual: Two-dimensional kinetic reference computer program (TDK)
The Two Dimensional Kinetics (TDK) computer program is a primary tool in applying the JANNAF liquid rocket thrust chamber performance prediction methodology. The development of a methodology that includes all aspects of rocket engine performance from analytical calculation to test measurements, that is physically accurate and consistent, and that serves as an industry and government reference is presented. Recent interest in rocket engines that operate at high expansion ratio, such as most Orbit Transfer Vehicle (OTV) engine designs, has required an extension of the analytical methods used by the TDK computer program. Thus, the version of TDK that is described in this manual is in many respects different from the 1973 version of the program. This new material reflects the new capabilities of the TDK computer program, the most important of which are described
Embodying Man: A Phenomenological Study of Body Image and Its Relationship to Masculinity
Many factors correlate with positive and negative body image issues in American culture today. Both men and women have a potential to struggle with negative and positive views of their bodies. However, body dissatisfaction has become commonly mistaken as an issue only impacting women. The present study sought to understand male body image and how it connects to a man’s view of his masculinity. The phenomenological study took place at a small, faith-based, residential campus in the Midwest and examined the experiences of eight male students at this institution. All participants mentioned family members as integral factors in helping them construct personal views of body image and mentioned their body types as indicators of perceived masculinity
Identification of Tylosin Photoreaction Products and Comparison of ELISA and HPLC Methods for Their Detection in Water
Tylosin is a widely used macrolide antibiotic for therapeutics and growth promotion in swine, beef cattle, and poultry production. Through various routes such as manure application, emission, inappropriate disposal, etc., tylosin enters the environment. The fate of tylosin in the environment is not yet fully understood. In this study, two photoreaction products of tylosin in water were identified as isotylosin A alcohol (E,Z) and isotylosin A aldol (E,Z). Tylosin A, B, C, D, isotylosin A alcohol, and isotylosin A aldol were purified, and immunological cross-reactivities of these tylosin-related compounds were tested with a specificity of 26% for tylosin B, 19% for tylosin C, 106% for tylosin D, 121% for isotylosin A alcohol, and 46% for isotylosin A aldol, compared to 100% for tylosin A. Competitive direct enzyme-linked immunosorbent assay (ELISA) for tylosin detection in water was compared with a high-performance liquid chromatography (HPLC) method by analyzing the same water samples from a study of tylosin dissipation in water. ELISA kits detect the other tylosin-related compounds besides tylosin A, which can result in differences in tylosin determination in water
Periodicity of high-order functions in the CNS Final progress report, year ending 30 Jun. 1971
Analysis of cerebral slow potentials underlying human attentive processes in central nervous syste
Plant essential oils synergize various pyrethroid insecticides and antagonize malathion in Aedes aegypti
Pyrethroid resistance is a significant threat to agricultural, urban and public health pest control activities. Because economic incentives for the production of novel active ingredients for the control of public health pests are lacking, this field is particularly affected by the potential failure of pyrethroid‐based insecticides brought about by increasing pyrethroid resistance. As a result, innovative approaches are desperately needed to overcome insecticide resistance, particularly in mosquitoes that transmit deadly and debilitating pathogens. Numerous studies have demonstrated the potential of plant essential oils to enhance the efficacy of pyrethroids. The toxicity of pyrethroids combined with plant oils is significantly greater than the baseline toxicity of either oils or pyrethroids applied alone, which suggests there are synergistic interactions between components of these mixtures. The present study examined the potential of eight plant essential oils applied in one of two concentrations (1% and 5%) to enhance the toxicity of various pyrethroids (permethrin, natural pyrethrins, deltamethrin and β‐cyfluthrin). The various plant essential oils enhanced the pyrethroids to differing degrees. The levels of enhancement provided by combinations of plant essential oils and pyrethroids in comparison with pyrethroids alone were calculated and synergistic outcomes characterized. Numerous plant essential oils significantly synergized a variety of pyrethroids; type I pyrethroids were synergized to a greater degree than type II pyrethroids. Eight plant essential oils significantly enhanced 24‐h mortality rates provided by permethrin and six plant essential oils enhanced 24‐h mortality rates obtained with natural pyrethrins. By contrast, only three plant essential plants significantly enhanced the toxicity of deltamethrin and β‐cyfluthrin. Of the plant essential oils that enhanced the toxicity of these pyrethroids, some produced varying levels of synergism and antagonism. Geranium, patchouli and Texas cedarwood oils produced the highest levels of synergism, displaying co‐toxicity factors of \u3e 100 in some combinations. To assess the levels of enhancement and synergism of other classes of insecticide, malathion was also applied in combination with the plant oils. Significant antagonism was provided by a majority of the plant essential oils applied in combination with this insecticide, which suggests that plant essential oils may act to inhibit the oxidative activation processes within exposed adult mosquitoes
A Systematic Research Review Assessing the Effectiveness of Pursuit Interventions in Spatial Neglect Following Stroke
Rehabilitation after stroke is imperative for patients with spatial neglect as it can help improve behavioural, social and cognitive outcomes in these patients, and therefore reduce the financial burden on public health services. The main aim of this review is to investigate the effectiveness of active pursuit eye movements for rehabilitation interventions in patients with spatial neglect following stroke. Potential papers for inclusion were gathered by searching key terms in four main databases (AMED, Global Health, PubMed/Medline and PsychInfo) in addition to screening relevant reference lists. Two reviewers independently selected papers for inclusion based on agreed inclusion criteria (n = 9 with 147 participants). Risk of bias was assessed using the QUADAS-2 tool. All papers reported a statistically significant result in patients who received an intervention which used pursuit eye movements, and this was reported both as a short-term (immediate) effect and as a sustained effect up to 8 weeks after treatment. These effects were also reported in comparison with interventions using saccadic eye movements. One study also reported increased neural activity in a number of brain regions following pursuit-based intervention. Overall, there is good evidence in support of pursuit intervention used in the rehabilitation of stroke and spatial neglect over and above traditional interventions based on saccadic eye movements. Future research should aim to increase sample sizes, provide information on statistical power, record accurate eye movement responses and use randomised designs to reduce selection bias
Mesoscale acid deposition modeling studies
The work performed in support of the EPA/DOE MADS (Mesoscale Acid Deposition) Project included the development of meteorological data bases for the initialization of chemistry models, the testing and implementation of new planetary boundary layer parameterization schemes in the MASS model, the simulation of transport and precipitation for MADS case studies employing the MASS model, and the use of the TASS model in the simulation of cloud statistics and the complex transport of conservative tracers within simulated cumuloform clouds. The work performed in support of the NASA/FAA Wind Shear Program included the use of the TASS model in the simulation of the dynamical processes within convective cloud systems, the analyses of the sensitivity of microburst intensity and general characteristics as a function of the atmospheric environment within which they are formed, comparisons of TASS model microburst simulation results to observed data sets, and the generation of simulated wind shear data bases for use by the aviation meteorological community in the evaluation of flight hazards caused by microbursts
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