196,064 research outputs found
Distribution of keratan sulphate and chondroitin sulphate in wild type and white mutant axolotl embryos during neural crest cell migration
No full textIn embryos of the white mutant axolotl, prospective pigment cells are unable to migrate from the neural crest (NC) due to a deficiency in the subepidermal extracellular matrix (ECM). This raises the question of the molecular nature of this functional defect. Some PGs can inhibit cell migration on ECM molecules in vitro, and an excess of this class of molecules in the migratory pathways of neural crest cells might cause the restricted migration of prospective pigment cells seen in the white mutant embryo. In the present study, we use several monoclonal antibodies against epitopes on keratan sulphate (KS) and chondroitin sulphate (CS) and LM immunofluorescence to examine the distribution of these glycosaminoglycans at initial (stage 30) and advanced (stage 35) stages of neural crest cell migration. Most KS epitopes are more widely distributed in the white mutant than in the wild type embryo, whereas CS epitopes show very similar distributions in mutant and wild type embryos. This is confirmed quantitatively by immunoblotting: certain KS epitopes are more abundant in the white mutant. TEM immunogold staining reveals that KS as well as CS are present both in the basal lamina and in the interstitial ECM in both types of embryos. It remains to be investigated whether the abundance of certain KS epitopes in the white mutant embryo might contribute to the deficiency in supporting pigment cell migration shown by its ECM
A safe road transport system : factors influencing injury outcome for car occupants
No full textGiven that over a million people are fatally injured in road accidents each year, the need for a systematic proactive approach is undeniable. The Swedish Road Administration (SRA) has developed a model for a safe road transport system based on the Vision Zero philosophy, to identify and prevent deviations from a safe system approach with regard to crashes. The overall objective of this thesis was: to study road crashes using this system approach, to identify whether the SRA model could be used to classify fatal crashes, and to identify system weaknesses as well as important factors that need to be addressed to further develop a safe road transport system.The thesis comprises four studies based on real-world crashes in Sweden. Three kinds of data were used in the studies: in-depth fatal crash data, in-depth car crashes involving cars fitted with an on-board crash pulse recorder, and observational data. In two studies, the aim was to investigate the interactions between a few safety performance indicators (SPIs), and how these indicators could be used to identify the most important factors in road crashes. The other two studies focused on SPIs of the vehicle and the road, to evaluate whether the SPIs used reflect the most important factors in the system. The aims of these two studies were also to present average crash severity, depending on collision partner as well as road safety standard.Most road traffic injuries are related to an interaction between the three components: the road, the vehicle and the road user. Therefore a system approach is needed to analyse crashes and to find preventive interventions. The SRA model was found to be useful for classifying in-depth fatal crashes. However, to identify weaknesses in the road traffic system, a more sophisticated model is needed. Based on crashes involving cars fitted with an on-board crash pulse recorder, crash severity was found to differ depending on collision partner. Frontal two-vehicle crashes and single-vehicle crashes with rigid roadside objects were shown to generate the highest crash severity. The least harmful crash type was single-vehicle crashes into deformable objects. Furthermore, crash severity was lower in crashes occurring on roads with a good safety rating than in those that occurred on roads with a poor safety rating. While it was found that a higher speed limit resulted in higher crash severity on roads with a poor safety rating, the opposite was found on roads with a good safety rating. The main reason for this was that lanes for traffic travelling in opposite directions were more often separated at higher speeds on roads with a good safety rating. On divided roads, no crashes resulted in a crash severity above the level corresponding to a 10% risk of sustaining serious or fatal injury. Simultaneous 100% fulfilment of a set of SPIs (sober driver, non-excessive speed, seat belt use and divided roads) also supports this finding, since only 5% of all fatalities on rural roads in Sweden occurred under these circumstances. Divided roads are therefore one of the most important SPIs for car occupants. The overall the results of the thesis indicates that it is necessary to establish a system approach, where the road infrastructure is based on the capabilities and limitations of human beings through good road and vehicle design.List of scientific papersI. Stigson H, Krafft M, Tingvall C (2008). "Use of fatal real-life crashes to analyze a safe road transport system model, including the road user, the vehicle, and the road." Traffic Inj Prev 9(5): 463-71. https://doi.org/10.1080/15389580802335240 II. Stigson H, Ydenius A, Kullgren A (2009). "Variation in crash severity depending on different vehicle types and objects as collision partner." International Journal of Crashworthiness. [Accepted] https://doi.org/10.1080/13588260902920589 III. Stigson H (2009). "Evaluation of safety ratings of roads based on frontal crashes with known crash pulse and injury outcome." Traffic Inj Prev 10(3): 273-8. https://doi.org/10.1080/15389580902864107 IV. Tingvall C, Stigson H, Eriksson L, Johansson R, Krafft M, Lie A (2009). "The role and properties of Safety Performance Indicators in target setting, projections and safety design of the road transport system." Accident Analysis & Prevention. [Submitted]</p
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
No full text"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Dr. Glendon Swarthout
No full textHosted by Roger M. Busfield, MSU Assistant Professor of Speech and Theater, Meet the Author is designed to introduce a general audience to a contemporary author and their work through in-depth interviews. This episode features a conversation between Dr. Glendon Swarthout, prolific author and English professor at MSU, and assistant professors Sam S. Baskett and Theodore B. Strandness
Simulation of thermal plant optimization and hydraulic aspects of thermal distribution loops for large campuses
No full textFollowing an introduction, the author describes Texas A&M University and its utilities system. After that, the author presents how to construct simulation models for chilled water and heating hot water distribution systems. The simulation model was used in a $2.3 million Ross Street chilled water pipe replacement project at Texas A&M University. A second project conducted at the University of Texas at San Antonio was used as an example to demonstrate how to identify and design an optimal distribution system by using a simulation model. The author found that the minor losses of these closed loop thermal distribution systems are significantly higher than potable water distribution systems. In the second part of the report, the author presents the latest development of software called the Plant Optimization Program, which can simulate cogeneration plant operation, estimate its operation cost and provide optimized operation suggestions. The author also developed detailed simulation models for a gas turbine and heat recovery steam generator and identified significant potential savings. Finally, the author also used a steam turbine as an example to present a multi-regression method on constructing simulation models by using basic statistics and optimization algorithms. This report presents a survey of the author??s working experience at the Energy Systems Laboratory (ESL) at Texas A&M University during the period of January 2002 through March 2004. The purpose of the above work was to allow the author to become familiar with the practice of engineering. The result is that the author knows how to complete a project from start to finish and understands how both technical and nontechnical aspects of a project need to be considered in order to ensure a quality deliverable and bring a project to successful completion. This report concludes that the objectives of the internship were successfully accomplished and that the requirements for the degree of Degree of Engineering have been satisfied
Intern experience at CH���M Hill, Inc.: an internship report
No full textIncludes author's vita"Submitted to the College of Engineering of Texas A&M University in partial
fulfillment of the requirement for the degree of Doctor of Engineering."Includes bibliographical referencesA review of the author's internship experience with CH���M HILL, Inc.
during the period September 1975 through May 1976 is presented. During this nine month
internship the author worked as an Engineer II in the Industrial Processes discipline of this
large consulting engineering firm... The author's prime responsibility was as one of three
lead design engineers on the design of a large wastewater treatment facility for a pulp mill
in Hoquiam, Washington owned by ITT Rayonier Inc. The work generally consisted of the design
of individual treatment units and associated piping and pumping. The purpose of the project
was to provide wastewater treatment capabilities that would satisfy the effluent limitations
(standards) imposed upon the mill by the State of Washington Department of Ecology and the
U.S. Environmental Protection Agency. The author's assignment also entailed necessary
interaction with the project manager and other CH���M HILL design engineers and support staff
members, the client's representatives, and representatives of two other consulting engineering
firms working on the project. Thus, the internship position at CH���M HILL provided considerable
experience coordinating the author's work with the work of other engineers, guiding the design
and administrative efforts of a support staff, and interacting regularly with the client and
other consulting firms. This broad exposure to a variety of engineering and organizational
problems provided a valuable educational experience
Transition to turbulence in a qblique shock-wave/boundary-layer interaction at M=15
No full textDirect numerical simulations are carried out for different forcing techniques to trigger transition during the interaction between an oblique shock-wave and a laminar boundary-layer at M = 1.5. Three forcing methods are used: a) forcing of oblique unstable modes, whose shape and behaviour are determined by the local linear stability theory, b) broadband free-stream acoustic disturbances, and c) a cold plasma flow control device. While the oblique-mode breakdown is dominant for low-amplitude forcing, long streaky structures drive the transition process in a high-amplitude disturbance environment. LES are also performed on the experimental setup by the Institute of Theoretical and Applied Mechanics (ITAM) from Novosibirsk State University with cold plasma actuation. As well as the disturbance type, the effect of Reynolds number and forcing amplitude will be investigated
- …
