1,598 research outputs found

    A Look at the Montana Securities Act and Its Relation to the Federal Securities Act

    Get PDF
    A Look at the Montana Securities Act and Its Relation to the Federal Securities Ac

    The Intrastate Exemption in the Light of the Securities Act Amendments of 1964

    Get PDF
    The Intrastate Exemption in the Light of the Securities Act Amendments of 196

    Measurement of local convective heat transfer coefficients from a smooth and roughened NACA-0012 airfoil: Flight test data

    Get PDF
    Wind tunnels typically have higher free stream turbulence levels than are found in flight. Turbulence intensity was measured to be 0.5 percent in the NASA Lewis Icing Research Tunnel (IRT) with the cloud making sprays off and around 2 percent with cloud making equipment on. Turbulence intensity for flight conditions was found to be too low to make meaningful measurements for smooth air. This difference between free stream and wing tunnel conditions has raised questions as to the validity of results obtained in the IRT. One objective of these tests was to determine the effect of free stream turbulence on convective heat transfer for the NASA Lewis LEWICE ice growth prediction code. These tests provide in-flight heat transfer data for a NASA-0012 airfoil with a 533 cm chord. Future tests will measure heat transfer data from the same airfoil in the Lewis Icing Research Tunnel. Roughness was obtained by the attachment of small, 2 mm diameter hemispheres of uniform size to the airfoil in three different patterns. Heat transfer measurements were recorded in flight on the NASA Lewis Twin Otter Icing Research Aircraft. Measurements were taken for the smooth and roughened surfaces at various aircraft speeds and angles of attack up to four degrees. Results are presented as Frossling number versus position on the airfoil for various roughnesses and angles of attack

    Problems in General Practice under the Federal Securities Act

    Get PDF
    Problems in General Practice Under the Federal Securities Ac

    Comparison of regulatory regions in the mitochondrial genomes of grasses

    Get PDF
    Abstract only availableRegulation of transcription in plant mitochondria is not well understood. The recent sequencing of the mitochondrial genomes of 10 closely related grasses allowed a comparative analysis of regulatory regions. To look for conserved regions and potential “swapped” regulatory regions, we have performed a comparative analysis of the upstream and downstream regions of all of the protein-coding genes in the mitochondrial genomes of eleven grasses: five mitochondrial types of maize (two fertile and three cytoplasmic male sterile), three other taxa within the genus (Zea mays ssp. parviglumis, Z. luxurians, Z. perennis), two close relatives (Tripsacum dactyloides, Sorghum bicolor), and an outgroup, rice. These genomes contain an average of 35 protein-coding genes, composed of 40 transcriptional units. Our analyses examined 1000 base pairs (bp) upstream of the first exon of each transcriptional unit and 1000 bp downstream of its last exon. The reference genome was NB, the most common fertile maize mitochondrial genotype. Compared with the genes from NB, more than half of the mitochondrial genes in the other genomes contain sequences that flank different genes in NB; we refer to these as “swapped” regions. More than 25% of the translocated sequences are longer than 100 bp, and 21 are greater than 500 bp. The longer sequences are more likely to have a regulatory function. In addition, some of these regions were found multiple times: 12 of the translocated gene-flanking regions were found flanking five or more other genes; four had sequences that were flanking ten or more. Furthermore, in Z. luxurians, Z. perennis and T. dactyloides, the co-transcribed 18S and 5S ribosomal RNA genes have been translocated immediately upstream of the start of cox1, with the 5S rRNA 3' end only 80 bp from the start of cox1 exon 1. This is a position that is difficult to rectify with the divergent transcriptional needs of the two types of genes.Plant Genomics Internship @ M

    Increased yield stability of field-grown winter barley (Hordeum vulgare L.) varietal mixtures through ecological processes

    Get PDF
    Crop variety mixtures have the potential to increase yield stability in highly variable and unpredictable environments, yet knowledge of the specific mechanisms underlying enhanced yield stability has been limited. Ecological processes in genetically diverse crops were investigated by conducting field trials with winter barley varieties (Hordeum vulgare), grown as monocultures or as three-way mixtures in fungicide treated and untreated plots at three sites. Mixtures achieved yields comparable to the best performing monocultures whilst enhancing yield stability despite being subject to multiple predicted and unpredicted abiotic and biotic stresses including brown rust (Puccinia hordei) and lodging. There was compensation through competitive release because the most competitive variety overyielded in mixtures thereby compensating for less competitive varieties. Facilitation was also identified as an important ecological process within mixtures by reducing lodging. This study indicates that crop varietal mixtures have the capacity to stabilise productivity even when environmental conditions and stresses are not predicted in advance. Varietal mixtures provide a means of increasing crop genetic diversity without the need for extensive breeding efforts. They may confer enhanced resilience to environmental stresses and thus be a desirable component of future cropping systems for sustainable arable farming

    Habitat fragmentation intensifies trade-offs between biodiversity and ecosystem services in a heathland ecosystem in southern England

    Get PDF
    While habitat fragmentation represents a major threat to global biodiversity, its impacts on provision of ecosystem services are largely unknown. We analysed biodiversity value and provision of multiple ecosystem services in 110 fragments of lowland heathland ecosystems in southern England, in which vegetation dynamics have been monitored for over 30 years. Decreasing fragment size was found to be associated with a decrease in biodiversity and recreational values, but an increase in relative carbon storage, aesthetic value and timber value. The trade-off between either biodiversity or recreational values with the other ecosystem services therefore became more pronounced as heathland size decreased. This was attributed to a higher rate of woody succession in smaller heathland fragments over the past three decades, and contrasting values of different successional vegetation types for biodiversity and provision of ecosystem services. These results suggest that habitat fragmentation can reduce the potential for developing “win win” solutions that contribute to biodiversity conservation while also supporting socio-economic development. Approaches to multi-purpose management of fragmented landscapes should therefore consider the potential trade-offs in ecosystem services and biodiversity associated with fragmentation, in order to make an effective contribution to sustainable development

    Heat Shock Protein-90 Inhibitors Enhance Antigen Expression on Melanomas and Increase T Cell Recognition of Tumor Cells

    Get PDF
    In an effort to enhance antigen-specific T cell recognition of cancer cells, we have examined numerous modulators of antigen-expression. In this report we demonstrate that twelve different Hsp90 inhibitors (iHsp90) share the ability to increase the expression of differentiation antigens and MHC Class I antigens. These iHsp90 are active in several molecular and cellular assays on a series of tumor cell lines, including eleven human melanomas, a murine B16 melanoma, and two human glioma-derived cell lines. Intra-cytoplasmic antibody staining showed that all of the tested iHsp90 increased expression of the melanocyte differentiation antigens Melan-A/MART-1, gp100, and TRP-2, as well as MHC Class I. The gliomas showed enhanced gp100 and MHC staining. Quantitative analysis of mRNA levels showed a parallel increase in message transcription, and a reporter assay shows induction of promoter activity for Melan-A/MART-1 gene. In addition, iHsp90 increased recognition of tumor cells by T cells specific for Melan-A/MART-1. In contrast to direct Hsp90 client proteins, the increased levels of full-length differentiation antigens that result from iHsp90 treatment are most likely the result of transcriptional activation of their encoding genes. In combination, these results suggest that iHsp90 improve recognition of tumor cells by T cells specific for a melanoma-associated antigen as a result of increasing the expressed intracellular antigen pool available for processing and presentation by MHC Class I, along with increased levels of MHC Class I itself. As these Hsp90 inhibitors do not interfere with T cell function, they could have potential for use in immunotherapy of cancer

    Gravitational quasinormal modes for Anti-de Sitter black holes

    Get PDF
    Quasinormal mode spectra for gravitational perturbations of black holes in four dimensional de Sitter and anti-de Sitter space are investigated. The anti-de Sitter case is relevant to the ADS-CFT correspondence in superstring theory. The ADS-CFT correspondence suggests a prefered set of boundary conditions.Comment: 12 pages, 6 figures in ReVTe

    Causes and Consequences of Broad-Scale Changes in the Distribution of Migratory Caribou (Rangifer tarandus) of Southern Hudson Bay

    Get PDF
    Understanding the factors driving changes in species distributions is fundamental to conservation, but for wide-ranging species this is often complicated by the need for broad-scale observations across space and time. In the last three decades, the location of summer concentrations of migratory caribou (Rangifer tarandus) in southern Hudson Bay (SHB), Canada, has shifted south and east as much as 500 km. We used long-term data (1987 – 2011) to test two hypotheses that could explain the distribution shift: forage depletion and anthropogenic disturbance. Over time and space, we compared the body size of live-captured adult female caribou, dietary quality from fecal nitrogen in July, the location of VHF- and GPS-collared female caribou in July, distribution of all-terrain vehicle (ATV) tracks and caribou tracks in August, and the proximity of collared caribou to sections of the coast with higher ATV activity in spring and summer. The forage depletion hypothesis was supported by greater body size and dietary quality in caribou of the eastern portion of SHB than in western SHB animals in 2009 – 11. The anthropogenic disturbance hypothesis was supported by the negative correlation of the distributions of ATV tracks and caribou tracks on the coast in 2010 and the fact that caribou avoided areas with ATV activity by 10 – 14 km. In 1987, collared caribou were observed largely along the coast in western SHB in mid-July, while in 2009 – 11, they were inland in western SHB and along the coast in eastern SHB. While these locations demonstrate a substantial change in summer distri­bution over three decades, we were unable to differentiate between forage depletion and anthropogenic disturbance as a single causal factor of the distribution shift.La comprĂ©hension des facteurs qui influencent les changements caractĂ©risant les distributions des espĂšces est fondamentale aux efforts de conservation, mais pour les espĂšces dont l’aire de distribution est Ă©tendue, ce principe est souvent compliquĂ© par la nĂ©cessitĂ© de faire des observations Ă  grande Ă©chelle, dans le temps et dans l’espace. Au cours des trois derniĂšres dĂ©cennies, l’emplacement des concentrations estivales du caribou migrateur (Rangifer tarandus) dans le sud de la baie d’Hudson (SBH), au Canada, s’est dĂ©placĂ© vers le sud et vers l’est dans une mesure de 500 km. Nous nous sommes appuyĂ©s sur des donnĂ©es de longue haleine (1987–2011) pour mettre Ă  l’épreuve deux hypothĂšses susceptibles d’expliquer ce changement en matiĂšre de distribution, soit l’appauvrissement du fourrage et la perturbation anthropique. Au fil du temps et de l’espace, nous avons comparĂ© la taille du corps des caribous femelles adultes capturĂ©es vivantes, la qualitĂ© de leur alimentation Ă  partir de l’azote fĂ©cal en juillet, l’emplacement des femelles portant un collier de type VHF ou GPS en juillet, la rĂ©partition des traces de vĂ©hicules tout terrain (VTT) et des pistes de caribou en aoĂ»t de mĂȘme que la proximitĂ© des caribous portant un collier aux tronçons de la cĂŽte oĂč la prĂ©sence de VTT est plus grande au printemps et Ă  l’étĂ©. L’hypothĂšse de l’appauvrissement du fourrage a Ă©tĂ© Ă©tayĂ©e par la plus grande taille du corps et la qualitĂ© de l’alimentation du caribou de la zone est du SBH comparativement Ă  celles du caribou de l’ouest du SBH entre 2009 et 2011. Pour sa part, l’hypothĂšse perturbation anthropique a Ă©tĂ© appuyĂ©e par la corrĂ©lation nĂ©gative caractĂ©risant la rĂ©partition des pistes de VTT et des traces de caribou sur la cĂŽte en 2010 et par le fait que les caribous sont restĂ©s Ă  l’écart des zones frĂ©quentĂ©es par les VTT dans une mesure de 10 Ă  14 km. En 1987, des caribous portant un collier ont Ă©tĂ© observĂ©s en grand nombre le long de la cĂŽte ouest du SBH Ă  la mi-juillet, tandis que de 2009 Ă  2011, ils ont Ă©tĂ© repĂ©rĂ©s Ă  l’intĂ©rieur des terres dans l’ouest du SBH et le long de la cĂŽte est du SBH. Bien que ces emplacements indiquent un important changement en matiĂšre de distribution estivale au cours de trois dĂ©cennies, nous n’avons pas Ă©tĂ© en mesure de faire une distinction entre l’appauvrissement du fourrage et la perturbation anthropique en tant que facteur causal unique du changement de distribution
    • 

    corecore