66,670 research outputs found
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Junctions podcast
This report outlines the development process for Junctions, an original, mini-drama podcast that explores racial bias in the context of everyday interaction. The report consists of three sections – The Podcast, Pilot Episode, and Future Episodes – each of which speaks to a different aspect of the program’s framework. It also includes nearly all of the planning documents I created during pre-production, production, and post-production.Radio-Television-Fil
Complexity and maintenance : a comparative study of object-oriented and structured methodologies : a thesis presented in partial fulfilment of the requirements for the degree of Master of Business Studies in Information Systems at Massey University
Maintenance has been found to be one of the most expensive phases in the life of an information system. It has been suggested that the use of object-oriented methods instead of traditional structured methods may be one way of reducing the cost of maintenance required for an information system. This thesis is an attempt to determine whether the object-oriented approach does in fact undergo a relatively smaller increase in complexity when subjected to a change in specifications than a similar system that is developed using a "structured methodology", and is therefore easier to maintain. The methodologies used in this study were Yourdon's (1989) Modern Structured Methodology and Booch's (1994) Object-Oriented methodology. The analysis phase of both methodologies were applied to the same case study twice in order to evaluate the effects of a change in the system's specifications. Once the two models for each methodology were complete, various metrics were applied to the structured system and a separate set of metrics were applied to the object-oriented system. The results of the models and the metrics were then analysed and validated in order to determine which system suffered a smaller proportional increase in complexity as a result of the changes to the system. It was found that overall, the object-oriented system proved to undergo a smaller increase in complexity, and it was therefore easier to maintain as a result of the changes than the structured system
Automated Pin-Dot Marking Effects on A709-Gr50 Steel Plate Fatigue Capacity
During fabrication of multi-piece steel bridge assemblies, markings are often made on the steel surface to identify/track individual pieces or to provide reference for fabrication layout or later erection. Automated marking methods such as computer numerically controlled (CNC) pin-dot marking offer fabrication efficiencies; however, for marked steel sections subjected to frequent or repeated loading (i.e. bridge girders) many code specifications require experimental testing to verify any marking effects on fatigue capacity. In this study, the effects of automated pin-dot markings on the fatigue capacity of A709-Gr50 bridge steel are experimentally investigated from 13 specimens considering 2 marking frequencies (corresponding to marking speeds of 50in./min and 10in./min), 2 applied stress ranges (35ksi and 45ksi), and 2 material orientations (both longitudinal and transverse plate rolling directions). Results from the 13 high-cycle fatigue tests, along with other fatigue test results from the literature indicate that the surface markings from the automated marking systems have no effect on the fatigue capacity of the A709-Gr50 plate. All marked specimens achieved higher fatigue capacities than would be expected for unmarked specimens meeting the AASHTO fatigue detail category ‘A’ designation
The Eigenvalue Problem for Linear and Affine Iterated Function Systems
The eigenvalue problem for a linear function L centers on solving the
eigen-equation Lx = rx. This paper generalizes the eigenvalue problem from a
single linear function to an iterated function system F consisting of possibly
an infinite number of linear or affine functions. The eigen-equation becomes
F(X) = rX, where r>0 is real, X is a compact set, and F(X)is the union of f(X),
for f in F. The main result is that an irreducible, linear iterated function
system F has a unique eigenvalue r equal to the joint spectral radius of the
functions in F and a corresponding eigenset S that is centrally symmetric,
star-shaped, and full dimensional. Results of Barabanov and of
Dranishnikov-Konyagin-Protasov on the joint spectral radius follow as
corollaries.Comment: 18 pages, 3 figure
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Isolation and characterization of Pisum sativum apyrases, PsNTP9 and PsNTP9-DM, cloned and expressed in Escherichia coli
Adenosine triphosphate (ATP) is widely known as a fuel source for many biochemical processes, and to a lesser degree also as a signaling molecule in plants and animals. When plants are subjected to biotic or abiotic stress or undergoing exocytosis, they release ATP into the extracellular matrix (ECM). The release of ATP sets off a signal transduction pathway, first rapidly increasing the concentrations of cytosolic calcium, reactive oxygen species, and nitric oxide. How these changes specifically influence physiology is the object of much research in both plants and animals. Some of the changes that are affected influence growth and development, stomatal function, and gravitropism. Apyrases and other phosphatases control the concentration of the released nucleotides by breaking phosphate bonds from nucleoside triphosphates and diphosphates. Research aimed at the discovery of receptors, signaling pathway components, and processes has been successful to some extent. There are now known purinergic receptors in both plants and animal cells.
We have cloned a truncated version of Pisum sativum (ps) NTP9. We used a pET-22B vector to add a histidine tag and transformed the vector into the BL21 Escherichia coli with a T7 promoter to enable IPTG induction of the LAC operon and expression of the enzyme. The pET-22B vector was incubated in separate samples with BL21 cells. Cells were propagated, and the expression of recombinant proteins PsNTP9, and separately, a double mutant PsNTP9-DM with a second calmodulin-binding domain, were induced ectopically. Cells were broken open by shaking them and mixing them with lysis buffer. Centrifugation was performed to separate the supernatant containing the released apyrases from the particulate wall fraction. The enzymes were purified by affinity chromatography, then their purity was evaluated by sodium dodecyl sulfate - polyacrylamide gel electrophoresis (SDS-PAGE). Western blots were performed to verify presence of the apyrases using a commercial anti-histidine antibody to detect PsNTP9 and PsNTP9-DM. Once suitable amounts of our proteins of interest were harvested, we performed Bradford assays to determine the protein concentration of the samples and carried out an apyrase activity assay to determine the specific activity of the purified enzymes and compare it to that of other known phosphatases.Plant Biolog
Field Experiment Tests for Discrimination against Hispanics in the U.S. Rental Housing Market
This article tests for discrimination against Hispanics in the U.S. rental housing market using e-mail correspondence with landlords advertising units online. We divide Hispanics into two groups: those that appear assimilated into American culture and recent immigrants. We find little difference in the treatment of assimilated Hispanics and whites; however, Hispanics we portray as recent immigrants receive less favorable treatment with margins of net discrimination as large as 6.89% of landlords. We also find discrimination varies significantly at the region level and by the ethnic composition of neighborhoods
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