TB113: A Field Test of Mating-Suppression Using the Spruce Budworm Sex Pheromone

Spruce budworm sex pheromone was dispersed from aircraft over forest land in Maine in late June, 1980. A major goal was to sample pheromone concentrations in air to determine whether the formulation would provide the steady, sustained release of chemical believed required for interfering with the mating process of the moths. Since pheromone was going to be applied for purposes of analyses of air, we believed we should also study some behavioral effects on spruce budworm populations. The principal body of data involved the ability of male budworm moths to orient to point sources of pheromone in pheromone-treated and untreated forest blocks, but attempts were also made to monitor fertility levels among females and to measure populations of eggs.https://digitalcommons.library.umaine.edu/aes_techbulletin/1073/thumbnail.jp

Considerations for Improving the Capacity and Performance of AeroMACS

The Aeronautical Mobile Airport Communications System (AeroMACS) has progressed from concept through prototype development, testing, and standards development and is now poised for the first operational deployments at nine US airports by the Federal Aviation Administration. These initial deployments will support fixed applications. Mobile applications providing connectivity to and from aircraft and ground-based vehicles on the airport surface will occur at some point in the future. Given that many fixed applications are possible for AeroMACS, it is necessary to now consider whether the existing capacity of AeroMACS will be reached even before the mobile applications are ready to be added, since AeroMACS is constrained by both available bandwidth and transmit power limitations. This paper describes some concepts that may be applied to improve the future capacity of AeroMACS, with a particular emphasis on gains that can be derived from the addition of IEEE 802.16j multihop relays to the AeroMACS standard, where a significant analysis effort has been undertaken

SCPS-TP, TCP, and Rate-Based Protocol Evaluation

Tests were performed at Glenn Research Center to compare the performance of the Space Communications Protocol Standard Transport Protocol (SCPS TP, otherwise known as "TCP Tranquility") relative to other variants of TCP and to determine the implementation maturity level of these protocols, particularly for higher speeds. The testing was performed over reasonably high data rates of up to 100 Mbps with delays that are characteristic of near-planetary environments. The tests were run for a fixed packet size, but for variously errored environments. This report documents the testing performed to date

Progress on the Development of Future Airport Surface Wireless Communications Network

Continuing advances in airport surface management and improvements in airport surface safety are required to enable future growth in air traffic throughout the airspace, as airport arrival and departure delays create a major system bottleneck. These airport management and safety advances will be built upon improved communications, navigation, surveillance, and weather sensing, creating an information environment supporting system automation. The efficient movement of the digital data generated from these systems requires an underlying communications network infrastructure to connect data sources with the intended users with the required quality of service. Current airport surface communications consists primarily of buried copper or fiber cable. Safety related communications with mobile airport surface assets occurs over 25 kHz VHF voice and data channels. The available VHF spectrum, already congested in many areas, will be insufficient to support future data traffic requirements. Therefore, a broadband wireless airport surface communications network is considered a requirement for the future airport component of the air transportation system. Progress has been made on defining the technology and frequency spectrum for the airport surface wireless communications network. The development of a test and demonstration facility and the definition of required testing and standards development are now underway. This paper will review the progress and planned future work

Toward ending segregation in the 1980s

The conflict concerning desegregation in the 1970s has roots and implications that extend beyond schooling to all aspects of life in metropolitan America. The issue is whether the ghettoization of blacks in areas distinct and separate from protected white enclaves will continue as the vehicle for imposing caste inequality. The challenge for the 1980s is to develop constructive policies and practices in education and training, jobs and housing, and urban development and taxation that will work to end the mutually destructive process of racial segregation across the national landscape. This article explores a number of control, incentive, market, and cooperative approaches to breaching the color line of racial ghettoization.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43868/1/11256_2005_Article_BF01956009.pd

Transposon Mutagenesis in Chlamydia trachomatis Identifies CT339 as a ComEC Homolog Important for DNA Uptake and Lateral Gene Transfer

Transposon mutagenesis is a widely applied and powerful genetic tool for the discovery of genes associated with selected phenotypes. Chlamydia trachomatis is a clinically significant, obligate intracellular bacterium for which many conventional genetic tools and capabilities have been developed only recently. This report describes the successful development and application of a Himar transposon mutagenesis system for generating single-insertion mutant clones of C. trachomatis. This system was used to generate a pool of 105 transposon mutant clones that included insertions in genes encoding flavin adenine dinucleotide (FAD)-dependent monooxygenase (C. trachomatis 148 [ct148]), deubiquitinase (ct868), and competence-associated (ct339) proteins. A subset of Tn mutant clones was evaluated for growth differences under cell culture conditions, revealing that most phenocopied the parental strain; however, some strains displayed subtle and yet significant differences in infectious progeny production and inclusion sizes. Bacterial burden studies in mice also supported the idea that a FAD-dependent monooxygenase (ct148) and a deubiquitinase (ct868) were important for these infections. The ct339 gene encodes a hypothetical protein with limited sequence similarity to the DNA-uptake protein ComEC. A transposon insertion in ct339 rendered the mutant incapable of DNA acquisition during recombination experiments. This observation, along with in situ structural analysis, supports the idea that this protein is playing a role in the fundamental process of lateral gene transfer similar to that of ComEC. In all, the development of the Himar transposon system for Chlamydia provides an effective genetic tool for further discovery of genes that are important for basic biology and pathogenesis aspects.S.D.L., Z.E.D., K.S.H., S.B., R.J.S., and P.S.H. were funded by NIH (AI126785)J.W. and P.S.H. were supported by NIH AI125929. P.S.H. was also supported by P20GM113117Support for genomic sequencing was supplemented by P20GM10363

Structural and ligand binding analyses of the periplasmic sensor domain of RsbU in Chlamydia trachomatis support a role in TCA cycle regulation

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154297/1/mmi14401-sup-0001-Supinfo.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154297/2/mmi14401_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154297/3/mmi14401.pd

Epigenetic change induced by in utero dietary challenge provokes phenotypic variability across multiple generations of mice

Transmission of epigenetic information between generations occurs in nematodes, flies and plants, mediated by specialised small RNA pathways, histone H3K9me3, H3K27me3, H4K16ac and DNA methylation 1-3 . In higher vertebrates, epidemiological and experimental evidence supports similar trans-generational effects 4,5 although the mechanisms that underpin these are incompletely understood 6-9 . We generated a luciferase reporter knock-in mouse for the imprinted Dlk1 locus, to visualise and track epigenetic fidelity across generations. We showed that exposure to high-fat diet (HFD) in pregnancy provokes sustained re-expression of the normally silent maternal Dlk1 allele in offspring, coincident with increased DNA methylation at the Dlk1 sDMR . Interestingly, maternal Dlk1 mis-expression was also evident in the next generation (F2), exclusively in animals derived from F1-exposed females. Oocytes from these females showed altered microRNA and gene expression, without any major changes in underlying DNA methylation, and correctly imprinted Dlk1 expression resumed in subsequent generations (F3 onwards). Our results reveal how canonical and non-canonical imprinting mechanisms enable the foetal epigenome to adapt to in utero challenge to modulate the properties of two successive generations of offspring