Alien Registration- Hovey, Walter E. (Bingham, Somerset County)

https://digitalmaine.com/alien_docs/8822/thumbnail.jp

Rigidification of algebras over multi-sorted theories

We define the notion of a multi-sorted algebraic theory, which is a generalization of an algebraic theory in which the objects are of different "sorts." We prove a rigidification result for simplicial algebras over these theories, showing that there is a Quillen equivalence between a model category structure on the category of strict algebras over a multi-sorted theory and an appropriate model category structure on the category of functors from a multi-sorted theory to the category of simplicial sets. In the latter model structure, the fibrant objects are homotopy algebras over that theory. Our two main examples of strict algebras are operads in the category of simplicial sets and simplicial categories with a given set of objects.Comment: This is the version published by Algebraic & Geometric Topology on 14 November 200

Analyzing the Effects of LED Traffic Signals on Urban Intersection Safety

In 2002, there were 1,299,000 crashes at signalized intersections in the United States. These crashes account for approximately 21 percent of total crashes and about 24 percent of all fatal and injury collisions. The social and financial impact of this number of collisions is substantial. The Federal Highway Administration (FHWA) and other agencies have recognized the detrimental effects of intersection crashes on our society and continue to fund research that will lead to a decrease in crash frequency. Numerous countermeasures have been tested for their potential to reduce crashes. Infrastructure improvements such as the construction of left-turn lanes, the removal of unwarranted signals and improvement of drainage through intersections have all proven to be effective at reducing crashes. Improving the visibility of traffic signals has also been cited as an important safety measure. Many intersection improvements are prohibitively expensive to implement—a drainage upgrade may cost in excess of $20,000, and new turn lanes may exceed$40,000. The financial impact of a countermeasure is always an important consideration to decision makers who are charged with the responsibility of allocating resources effectively. Low-cost safety countermeasures have become highly desirable as funding for transportation projects becomes more limited. Light emitting diodes (LEDs) have been used in various applications since their invention more than 40 years ago. As the new style of lighting gained popularity in other disciplines, engineers began to recognize the potential for LEDs in traffic applications. Traffic signal bulbs account for approximately 90 percent of the total energy usage at a typical intersection. By converting incandescent bulbs to LEDs, energy consumption can be decreased by about 80 percent. The California Department of Transportation (Caltrans) was one of the first agencies to realize large-scale cost saving by using LEDs. In 2003, Caltrans saved taxpayers $10 million per year by converting state-operated signals to LED. LED use became more widespread in the traffic industry as other government entities became aware of the potentially massive energy savings, eventually leading to the adoption of standard specifications and federal energy requirements for traffic signal modules. Conversion to LEDs has triggered other benefits besides the well-known energy reduction. They do not burn or distort lens covers, they may help preserve intersection wiring by drawing less power and they appear brighter than conventional signals. All of these advantages may also lead to an impact in another sector of traffic engineering—intersection safety. Visibility of LEDs seems to be superior, which could positively affect driver behavior. Reduced maintenance on the fixtures decreases the exposure of workers to traffic and the total number of work zones required at intersections. Also, the minimal energy usage allows for the use of battery backup systems to operate the intersection during a power outage. Could all of these factors combined improve overall intersection safety? The objective of this study was to use empirical Bayes estimation to determine whether there was a noticeable decrease in crashes at signalized intersections that have been converted to LED signals. In the field of traffic engineering, little research has been published about the safety benefits of increased signal visibility, though it has always been considered inherently beneficial. A study by Thomas et al. discusses the high reduction in crashes and high cost-benefit ratio for projects that replaced pedestal-mounted signals with more visible mast-arm-mounted ones. Improved traffic signal visibility was determined to be a cost-effective safety strategy. The Institute of Transportation Engineers cites improved signal visibility as a useful safety measure to be considered for implementation. LED signals are specifically described as being brighter and more conspicuous during inclement weather. Engineers have begun to utilize LEDs in railroad crossings as a potential safety improvement due to improved visibility and longer life. Flashing lights are installed horizontally at approaches to warn drivers of a train

Operations on integral lifts of K(n)

This very rough sketch is a sequel to arXiv:1808.08587; it presents evidence that operations on lifts of the functors K(n) to cohomology theories with values in modules over valuation rings of local number fields, indexed by Lubin-Tate groups of such fields, are extensions of the groups of automorphisms of the indexing group laws, by the exterior algebras on the normal bundle to the orbits of the group laws in the space of lifts.Comment: \S 2.0 hopefully less cryptic. To appear in the proceedings of the 2015 Nagoya conference honoring T Ohkawa. Comments very welcome

Determining the Statistical Significance of Observed Frequencies of Short DNA Motifs in a Genome

Until recently over 90 percent of the DNA in the human genome was considered junk DNA, with no known function. However, this non-coding DNA is now known to harbor elements that perform important functions in gene regulation. In particular, there is currently much interest in the search for short DNA motifs collectively known as cis-regulatory elements. Most studies attempt to identify these elements by means of cross-species comparisons. We have approached the problem of finding cis-regulatory elements by searching for conserved DNA motifs within genomes. This requires searching for DNA motifs that are repeated in the genomes either more or less frequently than expected by random chance. However, the usual chi-squared test cannot be used to test for the statistical significance of any observed frequency since overlapping regions of the genome are checked for DNA motif matches. We present here a statistical measure that has been developed to quantify the expectation and variance of the frequency of a given DNA motif in a given target sequence that may contain overlapping regions

Determining the Statistical Significance of Observed Frequencies of Short DNA Motifs in a Genome

Until recently over 90 percent of the DNA in the human genome was considered junk DNA, with no known function. However, this non-coding DNA is now known to harbor elements that perform important functions in gene regulation. In particular, there is currently much interest in the search for short DNA motifs collectively known as cis-regulatory elements. Most studies attempt to identify these elements by means of cross-species comparisons. We have approached the problem of finding cis-regulatory elements by searching for conserved DNA motifs within genomes. This requires searching for DNA motifs that are repeated in the genomes either more or less frequently than expected by random chance. However, the usual chi-squared test cannot be used to test for the statistical significance of any observed frequency since overlapping regions of the genome are checked for DNA motif matches. We present here a statistical measure that has been developed to quantify the expectation and variance of the frequency of a given DNA motif in a given target sequence that may contain overlapping regions

Sequestered Alkaloid Defenses in the Dendrobatid Poison Frog Oophaga pumilio Provide Variable Protection from Microbial Pathogens

Most amphibians produce their own defensive chemicals; however, poison frogs sequester their alkaloid-based defenses from dietary arthropods. Alkaloids function as a defense against predators, and certain types appear to inhibit microbial growth. Alkaloid defenses vary considerably among populations of poison frogs, reflecting geographic differences in availability of dietary arthropods. Consequently, environmentally driven differences in frog defenses may have significant implications regarding their protection against pathogens. While natural alkaloid mixtures in dendrobatid poison frogs have recently been shown to inhibit growth of non-pathogenic microbes, no studies have examined the effectiveness of alkaloids against microbes that infect these frogs. Herein, we examined how alkaloid defenses in the dendrobatid poison frog, Oophaga pumilio, affect growth of the known anuran pathogens Aeromonas hydrophila and Klebsiella pneumoniae. Frogs were collected from five locations throughout Costa Rica that are known to vary in their alkaloid profiles. Alkaloids were isolated from individual skins, and extracts were assayed against both pathogens. Microbe subcultures were inoculated with extracted alkaloids to create dose-response curves. Subsequent spectrophotometry and cell counting assays were used to assess growth inhibition. GC-MS was used to characterize and quantify alkaloids in frog extracts, and our results suggest that variation in alkaloid defenses lead to differences in inhibition of these pathogens. The present study provides the first evidence that alkaloid variation in a dendrobatid poison frog is associated with differences in inhibition of anuran pathogens, and offers further support that alkaloid defenses in poison frogs confer protection against both pathogens and predators

Homotopy theory of modules over operads in symmetric spectra

We establish model category structures on algebras and modules over operads in symmetric spectra, and study when a morphism of operads induces a Quillen equivalence between corresponding categories of algebras (resp. modules) over operads.Comment: Corrigendu

College students and cyberbullying: how social media use affects social anxiety and social comparison

Cyberbullying is defined as aggression intending to inflict harm on others by electronic communication technologies. Cyberbullying has become more common as social media has grown and is accompanied by negative mental health consequences. Research on cyberbullying and mental health in adolescents suggests cyberbullying victimization moderates the relationship between social comparison and social anxiety, but little is known about this phenomenon in college students. Therefore, the objective of this study was to explore the relationship between cyberbullying, social anxiety, and social comparison amongst college students. A convenience sample of 486 undergraduate students from southern Texas and northern Ohio completed a PyschData survey that assessed social anxiety, social comparison, experiences with be a cyberbullying victim, perpetrator, or both. We found that social anxiety was associated with cyberbullying victimization and perpetration; however, social comparison was not. Cyberbullying victimization was not a moderator between social comparison and anxiety, suggesting that unlike adolescence, college students\u27 experiences with these constructs may be unique to their developmental level

Excision for simplicial sheaves on the Stein site and Gromov's Oka principle

A complex manifold $X$ satisfies the Oka-Grauert property if the inclusion \Cal O(S,X) \hookrightarrow \Cal C(S,X) is a weak equivalence for every Stein manifold $S$, where the spaces of holomorphic and continuous maps from $S$ to $X$ are given the compact-open topology. Gromov's Oka principle states that if $X$ has a spray, then it has the Oka-Grauert property. The purpose of this paper is to investigate the Oka-Grauert property using homotopical algebra. We embed the category of complex manifolds into the model category of simplicial sheaves on the site of Stein manifolds. Our main result is that the Oka-Grauert property is equivalent to $X$ representing a finite homotopy sheaf on the Stein site. This expresses the Oka-Grauert property in purely holomorphic terms, without reference to continuous maps.Comment: Version 3 contains a few very minor improvement