69 research outputs found

    Geophysical Studies in the Southwest Pacific : Primarily Studies of Crustal Structure between New Zealand and Antarctica

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    Geophysical data - primarily magnetic field measurements, bathymetry, and seismicity data - are presented for the area between New Zealand and Antarctica from approximately 145[degrees]W to 155[degrees]E. The data are used to determine the structure of the Pacific-Antarctic boundary, the oceanic part of the Pacific plate and the area of intersection of the Indian, Pacific and Antarctic plates. In the southwest Pacific basin the magnetic anomalies are very clear and an extensive pattern of anomaly lineations with some offsets is mapped. The magnetic anomalies show that the uniform Pacific basin area formed between about 83 and 63 mybp. The Pacific-Antarctic boundary is shown to differ either side of about 175[degrees]W. To the east it is a relatively uniform aseismic spreading ridge, offset by some transform faults. West of 175[degrees]W, to 161[degrees]E, the boundary consists of a seismically active zone of disturbed bathymetry and magnetic anomalies striking about N.70[degrees]W. The zone, the Pacific-Antarctic fracture zone, probably consists of several fractures striking about N45[degrees]W. The area between the Pacific-Antarctic boundary and the southwest Pacific basin represents the interval 10 to -55 mybp, and only in the east are anomaly lineations clear. The Indian-Antarctic Pacific triple junction is near 61.5[degrees]S, 161[degrees]E and is a stable ridge-fault-fault junction; the Indian-Antarctic boundary being the ridge. Plate tectonics is applied to the area and the structure is shown to fit, and be explained by a different rotation pole for each of the major intervals indicated by the structure, i.e. 0-10 mybp, 10-63 mybp and 63-80 mybp. The poles, with rotation rates deduced from the magnetic anomalies, are used to reconstruct the position of New Zealand relative to Antarctica at 80 mybp. The two continents probably started to separate at close to 83 mybp. The times of the major changes of structure and plate movement in the area are shown to coincide with major plate movement changes in the southwest Pacific area and in the rest of the world. A new method for determining poles of rotation, based only on epicentre locations is presented, The method is applied to independently determine the Indian-Pacific, Pacific-Antarctic and Indian-Antarctic poles. The poles should form a consistent. set and they do. The method yields effectively instantaneous poles, is quantitative, and is applicable to most plate boundaries. Earthquake magnitude-frequency relationship b values for the plate boundaries in the area are determined. Comparisons with results from elsewhere indicate an association of high b with high temperature and conversely. Several factors which have previously been suggested as determining b value are shown to not be determinants. A revised and extended magnetic reversal time scale based on model studies of the southwest Pacific basin anomalies is presented. Other model studies indicate that a magnetized layer thickness of at least 2 km is probable. Variations of anomaly amplitudes are studied. A detailed study of the application of numerical correlation techniques to magnetic anomalies is presented. It is concluded that horizontal scale variations and discontinuities in profiles can be critical. Methods for over-coming some of the problems, and for determining quantitative error estimates, are. given. The methods, and conclusions, are applicable to any correlation problem

    Task Organization and Time Management: Handling Email, Scheduling Time, and Prioritizing To-Do Lists

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    Faculty must juggle competing demands of scholarship, teaching, and service. Maintaining work-­‐life balance requires effective use of limited time. A BGSU faculty learning community formed to identify and explore efficiency practices, while developing accountability for implementing them. During this interactive roundtable, we will share experiences and tips: batching email and removing notifications, developing hyper-­‐ detailed calendars, protecting writing time, capturing “useless” downtime, assessing tasks based on importance and urgency, creating a social support system, and learning when and how to say no. An important lesson is that time management tools are not “one-­‐size-­‐fits-­‐all,” and particular techniques resonate more with individual faculty

    The Nippon Foundation—GEBCO Seabed 2030 Project: The Quest to See the World’s Oceans Completely Mapped by 2030

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    Despite many of years of mapping effort, only a small fraction of the world ocean’s seafloor has been sampled for depth, greatly limiting our ability to explore and understand critical ocean and seafloor processes. Recognizing this poor state of our knowledge of ocean depths and the critical role such knowledge plays in understanding and maintaining our planet, GEBCO and the Nippon Foundation have joined forces to establish the Nippon Foundation GEBCO Seabed 2030 Project, an international effort with the objective of facilitating the complete mapping of the world ocean by 2030. The Seabed 2030 Project will establish globally distributed regional data assembly and coordination centers (RDACCs) that will identify existing data from their assigned regions that are not currently in publicly available databases and seek to make these data available. They will develop protocols for data collection (including resolution goals) and common software and other tools to assemble and attribute appropriate metadata as they assimilate regional grids using standardized techniques. A Global Data Assembly and Coordination Center (GDACC) will integrate the regional grids into a global grid and distribute to users world-wide. The GDACC will also act as the central focal point for the coordination of common data standards and processing tools as well as the outreach coordinator for Seabed 2030 efforts. The GDACC and RDACCs will collaborate with existing data centers and bathymetric compilation efforts. Finally, the Nippon Foundation GEBCO Seabed 2030 Project will encourage and help coordinate and track new survey efforts and facilitate the development of new and innovative technologies that can increase the efficiency of seafloor mapping and thus make the ambitious goals of Seabed 2030 more likely to be achieved

    The microbiota regulates murine inflammatory responses to toxin-induced CNS demyelination but has minimal impact on remyelination.

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    The microbiota is now recognized as a key influence on the host immune response in the central nervous system (CNS). As such, there has been some progress toward therapies that modulate the microbiota with the aim of limiting immune-mediated demyelination, as occurs in multiple sclerosis. However, remyelination-the regeneration of myelin sheaths-also depends upon an immune response, and the effects that such interventions might have on remyelination have not yet been explored. Here, we show that the inflammatory response during CNS remyelination in mice is modulated by antibiotic or probiotic treatment, as well as in germ-free mice. We also explore the effect of these changes on oligodendrocyte progenitor cell differentiation, which is inhibited by antibiotics but unaffected by our other interventions. These results reveal that high combined doses of oral antibiotics impair oligodendrocyte progenitor cell responses during remyelination and further our understanding of how mammalian regeneration relates to the microbiota.This work was supported by grants from UK Multiple Sclerosis Society, The British Trust for the Myelin Project, MedImmune, The Adelson Medical Research Foundation, Wellcome Trust, BBSRC, the Leverhulme Trust and a core support grant from the Wellcome Trust and MRC to the Wellcome Trust - Medical Research Council Cambridge Stem Cell Institute. CEM was supported by grants from the Jean Shanks Foundation and the James Baird Fund, AGF was supported by an ECTRIMS fellowship and OBZ received a BIRAX fellowship

    Genetic and Other Contributions to Alcohol Intake in Rhesus Macaques ( Macaca mulatta )

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    The etiology of alcoholism and alcohol abuse, like many other complex diseases, is heterogeneous and multifactorial. Numerous studies demonstrate a genetic contribution to variation in the expression of alcohol-related disorders in humans. Over the past decade, nonhuman primates have emerged as a valuable model for some aspects of human alcohol abuse because of their phylogenetic proximity to humans. Long-term, longitudinal studies of rhesus macaques ( Macaca mulatta ) have provided much insight into environmental influences, especially early life experiences, on alcohol consumption and behavior patterns that characterize alcohol intake later in life. It is not known, however, whether there is a genetic component as well to the variation seen in alcohol consumption in rhesus macaques. A significant genetic component to variation in alcohol consumption in rhesus macaques would show for the first time that like humans, for nonhuman primates additive genetic influences are important. Moreover, their use as a model for alcohol-related disorders in humans would have even greater relevance and utility for designing experiments incorporating the expanding molecular genetics field, and allow researchers to investigate the interaction among the known environmental influences and various genotypes. Methods : In this study, we investigate factors contributing to variation in alcohol consumption of 156 rhesus macaques collected over 10 years when subjects were adolescent in age, belonging to a single extended pedigree, with each cohort receiving identical early rearing backgrounds and subsequent treatments. To measure alcohol consumption each animal was provided unfettered simultaneous access both to an aspartame-sweetened 8.4% (v/v) alcohol-water solution, the aspartame-sweetened vehicle, and to water for 1 hour each day during the early afternoon between 13:00 and 15:00 in their home cages for a period of 5 to 7 weeks. We use multiple regression to identify factors that significantly affect alcohol consumption among these animals and a maximum likelihood program (ASReml) that, controlling for the significant factors, estimates the genetic contribution to the variance in alcohol consumption. Results : Multiple regression analysis identified test cohort and rearing environment as contributing to 57 and 2%, respectively, of the total variance in alcohol consumption. Of the remaining 41% of the variance about half (19.8%) was attributable to additive genetic effects using a maximum likelihood program. Conclusion : This study demonstrates that, as in humans, there are additive genetic factors that contribute to variation in alcohol consumption in rhesus macaques, with other nongenetic factors accounting for substantial portions of the variance in alcohol consumption, Our findings show the presence of an additive genetic component and suggest the potential utility of the nonhuman primate as a molecular genetics tool for understanding alcohol abuse and alcoholism.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66182/1/j.1530-0277.2006.00044.x.pd

    Estimation in a multiplicative mixed model involving a genetic relationship matrix

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    Genetic models partitioning additive and non-additive genetic effects for populations tested in replicated multi-environment trials (METs) in a plant breeding program have recently been presented in the literature. For these data, the variance model involves the direct product of a large numerator relationship matrix A, and a complex structure for the genotype by environment interaction effects, generally of a factor analytic (FA) form. With MET data, we expect a high correlation in genotype rankings between environments, leading to non-positive definite covariance matrices. Estimation methods for reduced rank models have been derived for the FA formulation with independent genotypes, and we employ these estimation methods for the more complex case involving the numerator relationship matrix. We examine the performance of differing genetic models for MET data with an embedded pedigree structure, and consider the magnitude of the non-additive variance. The capacity of existing software packages to fit these complex models is largely due to the use of the sparse matrix methodology and the average information algorithm. Here, we present an extension to the standard formulation necessary for estimation with a factor analytic structure across multiple environments

    Within- and across-breed genomic prediction using whole-genome sequence and single nucleotide polymorphism panels

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    International audienceBackground Currently, genomic prediction in cattle is largely based on panels of about 54k single nucleotide polymorphisms (SNPs). However with the decreasing costs of and current advances in next-generation sequencing technologies, whole-genome sequence (WGS) data on large numbers of individuals is within reach. Availability of such data provides new opportunities for genomic selection, which need to be explored.MethodsThis simulation study investigated how much predictive ability is gained by using WGS data under scenarios with QTL (quantitative trait loci) densities ranging from 45 to 132 QTL/Morgan and heritabilities ranging from 0.07 to 0.30, compared to different SNP densities, with emphasis on divergent dairy cattle breeds with small populations. The relative performances of best linear unbiased prediction (SNP-BLUP) and of a variable selection method with a mixture of two normal distributions (MixP) were also evaluated. Genomic predictions were based on within-population, across-population, and multi-breed reference populations.ResultsThe use of WGS data for within-population predictions resulted in small to large increases in accuracy for low to moderately heritable traits. Depending on heritability of the trait, and on SNP and QTL densities, accuracy increased by up to 31 %. The advantage of WGS data was more pronounced (7 to 92 % increase in accuracy depending on trait heritability, SNP and QTL densities, and time of divergence between populations) with a combined reference population and when using MixP. While MixP outperformed SNP-BLUP at 45 QTL/Morgan, SNP-BLUP was as good as MixP when QTL density increased to 132 QTL/Morgan.ConclusionsOur results show that, genomic predictions in numerically small cattle populations would benefit from a combination of WGS data, a multi-breed reference population, and a variable selection method

    Crop Updates 2003 - Geraldton

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    This session covers twenty eight papers from different authors Seasonal Outlook: What is in store for 2003, David Stephens, Department of Agriculture Examining The Management Options For Wheat Crops In The Coming Season, James Fisher, Department of Agriculture GMO’s – what do they offer? Ian Edwards, Grain Bio Tech Australia Pty Ltd The Big Gamble – Wheat prices for 2003, Dennis Wise, Profarmer Market outlook for other grains, Andrew Young, General Manager Agricorp Stripe rust – where to now for the WA wheat industry? Robert Loughman, Ciara Beard and Greg Shea, Department of Agriculture Baudin and Hamlin – new generation of malting barley developed in Western Australia, Blakely Paynter, Roslyn Jettner and Kevin Young, Department of Agriculture DBM in Canola, Kevin Walden, Department of Agriculture The latest on Lupin diseases, Geoff Thomas, Department of Agriculture Wheat variety performance in 2002 compared to the long term, Robin Wilson, Iain Barclay, Robyn McLean, Robert Loughman, Jenny Garlinge, Bill Lambe, Neil Venn and Peter Clarke, Department of Agriculture Do wide rows drought proof lupins on red loam? Martin Harries, Bob French, Wayne Parker and Murray Blyth, Department of Agriculture Do wide rows drought proof lupins on a sandy loam? Martin Harries, Bob French, Wayne Parker and Murray Blyth, Department of Agriculture Profit Proving Precision Agriculture, Peter Norris, Agronomy For Profit, Greg Lyle, CSIRO Land and Water, Yuna Farm Improvement Group Annual ryegrass seedbanks: the good, the bad, and the ugly, Kathryn Steadman, University of Western Australia, Amander Ellery, CSIRO Plant Industry, Sally C Peltzer, Department of Agriculture Wheat management packages for low rainfall areas, Kari-Lee Falconer, Department of Agriculture Ground water 1. Atrazine, Russell Speed, Department of Agriculture Groundwater 2. Current Trends, Russell Speed, Department of Agriculture Herbicide tolerance of wheat, lupins and pastures, Terry Piper and Harmohinder Dhammu, Department of Agriculture Farming with Tramlines, Bindi Webb, Paul Blackwell, Department of Agriculture, Phil Logue, Binnu, Nigel Moffat, Geraldton, Rohan Ford, Binnu, Miles Obst, Mingenew, The role of green manure crops in renovating poor performing paddocks: What’s it worth? Frances Hoyle, Leanne Schulz and Judith Devenish Department of Agriculture The looming threat of wild radish, Peter Newman, Department of Agriculture Does one ‘size’ fit all? Grant Morrow, Syngenta Crop Protection Climate Forecasts on the Internet, Ian Foster and David Stephens, Department of Agriculture Moisture delving = more reliable lupin establishment, Paul Blackwell, and Wayne Parker, Department of Agriculture Tramline Designs for better Weed control and Wheat value from non-spraying tramlines in a dry season, Paul Blackwell, Bindi Webb and Darshan Sharma, Department of Agriculture Biserrula Grazing Trial, Marnie Thomas, Department of Agriculture Performance of IT and TT canola varieties in the medium and high rainfall agzones of W.A., 2001-02, Graham Walton, Hasan Zaheer and Paul Carmody, Department of Agriculture Rapid Catchment Appraisal in Northern Agricultural Region, Mike Clarke, Paul Raper, Department of Agricultur
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