255 research outputs found
From Twisted Quantum Loop Algebras to Twisted Yangians
We prove how the Yangian of in its RTT presentation and
Olshanski's twisted Yangians for the orthogonal and symplectic Lie algebras can
be obtained by a degeneration process from the corresponding quantum loop
algebra and some of its twisted analogues
fMRI studies of amblyopia: Pediatric and adult perspectives
Functional magnetic resonance imaging (fMRI) is currently the technique of choice for mapping functional neuroanatomy in humans, and over the past 15 years there has been a dramatic growth in the number of studies that provide brain-behavior correlations in normal healthy adults. More recently, a few studies have begun to make such measures in healthy children. In addition, fMRI is increasingly being applied to study brain function in subjects with neurological disease. The overall aim of these studies was to apply fMRI methods to the study of amblyopia, the most prevalent developmental vision disorder. Amblyopia develops early in life, usually before 5 years old, and is most treatable during childhood. Our approach was to study both children and adults with either the strabismic or the anisometropic type of amblyopia. In our first experiment (Chapter 3), we applied fMRI techniques to map retinotopic visual organization in children. We conclude that cortical visual organization is measurable and highly mature in children aged 9 to 12 years. In our second experiment (Chapter 4), we applied similar techniques to adults with amblyopia. We conclude that visual field organization is abnormal in the brains of these adults. In our final experiment (Chapter 5), we applied these same techniques to children with amblyopia, and observed abnormalities similar to those seen in adults. These studies present a novel neurological characterization of amblyopia, and provide a basis for further studies of human visual development, in health and disease
On the slice genus of links
We define Casson-Gordon sigma-invariants for links and give a lower bound of
the slice genus of a link in terms of these invariants. We study as an example
a family of two component links of genus h and show that their slice genus is
h, whereas the Murasugi-Tristram inequality does not obstruct this link from
bounding an annulus in the 4-ball.Comment: Published by Algebraic and Geometric Topology at
http://www.maths.warwick.ac.uk/agt/AGTVol3/agt-3-30.abs.htm
Low-speed characteristics in pitch of a 34 degree sweptforward wing with circular-arc airfoil sections
A Software Pipeline for Analyzing Viral Sequences in Bacterial Genomes
Pseudomonas aeruginosa is an opportunistic bacterium that can cause serious infections in individuals with compromised immune systems or conditions such as cystic fibrosis. Pseudomonas infections are known to become worse after the bacterial population in a patient has been infected by a group of prophages, a type of virus that insert its genetic sequence into its host’s genome. To help researchers investigate and understand why these viral sequences have this effect on Pseudomonas, we have developed a software pipeline that identifies and analyzes viral insertions into bacterial genomes. This pipeline searches Pseudomonas genomes against the sequences of 50 phages known to target the bacterium, recording the length of a match, its location in its host’s genome, and which strand it occurs on. In addition to gathering summary statistics, our software generates plots showing which portions of each virus are most often found inserted into Pseudomonas genomes; in these graphs, each viral genome is labeled with known protein families and domains. These gathered data will support understanding of prophage insertion patterns and correlation with virulence, possibly aiding in developing treatment regimes
Fiber optic hydrophone
Includes bibliographical references.Missing some pages.Optical fiber technology has become one of the most important new developments in communications. Telecommunications and broadcast communications have become the most visible applications of fiber optics. The computer terminals in the lab at Northern Illinois University communicate over a fiber optic local area network (LAN). These and many other applications illustrate the utility of fiber optics in electrical engineering. What is it about fiber optics that makes them so useful in communications? How can light transmit a telephone call or a television program? The answers to these questions lies in the fact that light is no different from microwaves and radio waves except for the frequency. In other words, light is another form of electromagnetic energy that can be harnessed. The optical region of the electromagnetic spectrum is from 3*10¹² Hz to 6*10¹⁵ Hz. This is higher than radio frequencies and microwave frequencies. And because light is the carrier in optical communication, it follows that optical systems offer a wider bandwidth than RF and microwave communication systems. In a typical system where the bandwidth is a fraction of the carrier frequency, it is possible to attain bandwidths on the order of 10⁶ Hz. This is why a single optical fiber can carry thousands of telephone and television channels simultaneously. Another advantage of optical communications is the immunity to interference. Because optical fibers are dielectrics, they do not conduct electricity and are thus immune to electrical discharge. The extremely high frequency of optical signals prevents most electromagnetic interference from distorting the signal. Thus, fiber optic telephone lines offer clearer transmission than coaxial cables. A third advantage of fiber optics is that glass fibers offer low attenuation compared to some media. At certain wavelengths it is possible for some fibers to have attenuation as low as 0.5 dBIkrn. This makes it practical to use fiber optics for longdistance communication links. Fiber optic cables have even been laid on the ocean floor to carry telephone channels between Europe and the United States. FIBER OPTIC SENSORS Another more specialized application of fiber optics is in sensors. This project is intended to demonstrate one example of a fiber optic sensor. In this experiment, I will demonstrate a moving-fiber displacement sensor to measure the amplitude and frequency of acoustic signals. This simple sensor is useful for detecting sounds in air or under water. This is one design for a sensor called a hydrophone. It can be used like a microphone to listen under water or to make measurements on sound waves in the water, similar to those performed by sonar. In this report, I will give a brief introduction to fiber optic technology and discuss their application to sensing. I will then talk about the specific components used in this experiment and give a summary of the tests performed. This paper will conclude with a brief discussion of the interferometric sensor concept used on board surface vessels and submarines in the Navy.B.S. (Bachelor of Science
Genetic Analysis of a Hybrid Swarm Between Two Pupflshes, Cyprinodon Pecosensis and C. Variegatus (Cyprlnodontidae): Geographical Pattern
Zoolog
Automation of Data Analysis in Formula 1
This paper explores economic solutions for Formula 1 racing companies who are interested in data visualization tools. The research was conducted on the current development of data gathering, data visualization, and data interpretation in Formula 1 racing. It was found that a large chunk of racing companies within the league needs an affordable, effective, and automated visualization tool for data interpretation. As data collection in Formula 1 arises, the need for faster and more powerful software increases. Racing companies profit off-brand exposure and the more a racing team wins, the more exposure they receive. The goal of the paper focuses on solving the issue of data visualization. It begins with the current state of Formula 1 and the background of the billion-dollar industry. Then, the criteria needed for an effective solution is discussed and is used to measure three different software solutions. The three solutions considered were Tableau, Power BI, and Python. Python earned the highest rating according to the criteria of process time, scalability, usability, customizable, and cost-effectiveness. As proof of concept, a demo was created using Python, specifically using the Python framework Dash, showing the simplicity and versatility of the software. Racing companies looking to save money should consider implementing Python into their data visualization to increase their odds of winning and rising in the rankings
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