25 research outputs found

    Monitoring the Water Bodies of the Mackenzie Delta by Remote Sensing Methods

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    In the Mackenzie Delta, Northwest Territories, the thousands of lakes, ponds, channels and waterways, connected in an apparently chaotic manner, present a major logistical problem for collecting information regarding the nature of this complex hydrologic system. The use of satellite images gives an economical and synoptic view of this isolated region, while special analysis techniques simplify the environmental appraisal. The use of (mathematical) morphological analysis of the surface waters imaged by the satellite allowed the authors to distinguish all water bodies, even when they were at the limit of the spatial resolution of the sensor. The technique further permitted the classification of these water bodies by their inter- and intra-connectivity. Another technique, termed chromaticity analysis, allows for the removal of atmospheric differences among images, which in turn enables the use of surface calibration data from one date to be used on images of other dates. This method was also used to generate quantitative maps of suspended sediment concentration levels. Together, these techniques permit the assessment of the hydrologic flow (or its hindrance) of sediment and nutrients for the sustenance of aquatic flora and fauna. They further supply a method for the mapping of access routes by water craft to all parts of the Delta.Key words: mathematical morphology, chromaticity analysis, remote sensing, Landsat, Mackenzie Delta, suspensdeeddi ment, hydrologic networkMots clés: morphologie mathématique, analyse par chromaticité, télédétection, Landsat, Delta du Mackenzie, sediments en suspension, réseau hydrologiqu

    Improved canine exome designs, featuring ncRNAs and increased coverage of protein coding genes OPEN

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    By limiting sequencing to those sequences transcribed as mRNA, whole exome sequencing is a costefficient technique often used in disease-association studies. We developed two target enrichment designs based on the recently released annotation of the canine genome: the exome-plus design and the exome-CDS design. The exome-plus design combines the exons of the CanFam 3.1 Ensembl annotation, more recently discovered protein-coding exons and a variety of non-coding RNA regions (microRNAs, long non-coding RNAs and antisense transcripts), leading to a total size of ≈152 Mb. The exome-CDS was designed as a subset of the exome-plus by omitting all 3' and 5' untranslated regions. This reduced the size of the exome-CDS to ≈71 Mb. To test the capturing performance, four exome-plus captures were sequenced on a NextSeq 500 with each capture containing four precapture pooled, barcoded samples. At an average sequencing depth of 68.3x, 80% of the regions and well over 90% of the targeted base pairs were completely covered at least 5 times with high reproducibility. Based on the performance of the exome-plus, we estimated the performance of the exome-CDS. Overall, these designs provide flexible solutions for a variety of research questions and are likely to be reliable tools in disease studies. In 2014, the first report detailing the design and performance of a whole exome sequencing (WES) enrichment assay for the dog was published by our group 1 . Aiming to selectively sequence all the regions that are transcribed to mRNA, WES is a reliable tool used to identify disease-causing or predisposing mutations at a fraction of the price of whole genome sequencing (WGS) studies. A limitation of WES is that it is based on our current knowledge of the annotation of the genome and that many disease causing mutations are likely to fall outside protein-coding regions. With new information becoming available, updates and extensions are required. Recently, an improved annotation for the dog genome has been published and new data on non-protein coding genes has been obtained 2 . Based on this data, two new target enrichment designs for dogs, called the exome-plus and the exome-CDS, were developed. The exome-plus offers the most comprehensive design. The exome-CDS is a subset of the exome-plus, focusing on the coding DNA sequences (CDS) by excluding the 3′ and 5′ untranslated regions (UTRs). Thes

    Recommendations for a national program of remote sensing in Zimbabwe

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    Prepared for the Scientific Council of Zimbabw

    Improved canine exome designs, featuring ncRNAs and increased coverage of protein coding genes

    No full text
    By limiting sequencing to those sequences transcribed as mRNA, whole exome sequencing is a cost-efficient technique often used in disease-association studies. We developed two target enrichment designs based on the recently released annotation of the canine genome: the exome-plus design and the exome-CDS design. The exome-plus design combines the exons of the CanFam 3.1 Ensembl annotation, more recently discovered protein-coding exons and a variety of non-coding RNA regions (microRNAs, long non-coding RNAs and antisense transcripts), leading to a total size of approximate to 152 Mb. The exome-CDS was designed as a subset of the exome-plus by omitting all 3' and 5' untranslated regions. This reduced the size of the exome-CDS to approximate to 71 Mb. To test the capturing performance, four exome-plus captures were sequenced on a NextSeq 500 with each capture containing four pre-capture pooled, barcoded samples. At an average sequencing depth of 68.3x, 80% of the regions and well over 90% of the targeted base pairs were completely covered at least 5 times with high reproducibility. Based on the performance of the exome-plus, we estimated the performance of the exome-CDS. Overall, these designs provide flexible solutions for a variety of research questions and are likely to be reliable tools in disease studies

    Improved canine exome designs, featuring ncRNAs and increased coverage of protein coding genes

    No full text
    By limiting sequencing to those sequences transcribed as mRNA, whole exome sequencing is a cost-efficient technique often used in disease-association studies. We developed two target enrichment designs based on the recently released annotation of the canine genome: the exome-plus design and the exome-CDS design. The exome-plus design combines the exons of the CanFam 3.1 Ensembl annotation, more recently discovered protein-coding exons and a variety of non-coding RNA regions (microRNAs, long non-coding RNAs and antisense transcripts), leading to a total size of approximate to 152 Mb. The exome-CDS was designed as a subset of the exome-plus by omitting all 3' and 5' untranslated regions. This reduced the size of the exome-CDS to approximate to 71 Mb. To test the capturing performance, four exome-plus captures were sequenced on a NextSeq 500 with each capture containing four pre-capture pooled, barcoded samples. At an average sequencing depth of 68.3x, 80% of the regions and well over 90% of the targeted base pairs were completely covered at least 5 times with high reproducibility. Based on the performance of the exome-plus, we estimated the performance of the exome-CDS. Overall, these designs provide flexible solutions for a variety of research questions and are likely to be reliable tools in disease studies

    Firm Bosses or Helpful Neighbours? The Ambiguity and Co-Construction of MNE Regional Management Mandates

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    As multinational enterprises (MNEs) increasingly disaggregate and disperse corporate headquarters (CHQ) activities, the allocation of regional management mandates (RMMs) to local operating subsidiaries is becoming more common. RMMs explicitly break with the traditional assumption of a clear separation between centralised and local decision-making. Yet we know little of how RMMs are enacted by the units involved, or how they evolve over time. Based on a case study of Unilever, we find that RMMs are inherently ambiguous, and identify circumstances under which ambiguity manifests and triggers cycles of sensemaking and sensegiving about the meaning of the mandate. These cycles result in the co-construction of the mandate by multiple units, with changes in RMM scope and governance over time. We also find that sensemaking and sensegiving are most intense among boundary-spanning middle managers. Our work challenges prevailing assumptions that mandates are largely unambiguous when assigned and are unilateral or dyadic accomplishments; demonstrates the importance of sub-unit level analysis in MNEs; and highlights the potential of structuration theory to enrich our understanding of sensemaking and sensegiving in organisations

    A comprehensive genomic history of extinct and living elephants

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    Elephantids are the world’s most iconic megafaunal family, yet there is no comprehensive genomic assessment of their relationships. We report a total of 14 genomes, including 2 from the American mastodon, which is an extinct elephantid relative, and 12 spanning all three extant and three extinct elephantid species including an ∼120,000-y-old straight-tusked elephant, a Columbian mammoth, and woolly mammoths. Earlier genetic studies modeled elephantid evolution via simple bifurcating trees, but here we show that interspecies hybridization has been a recurrent feature of elephantid evolution. We found that the genetic makeup of the straight-tusked elephant, previously placed as a sister group to African forest elephants based on lower coverage data, in fact comprises three major components. Most of the straight-tusked elephant’s ancestry derives from a lineage related to the ancestor of African elephants while its remaining ancestry consists of a large contribution from a lineage related to forest elephants and another related to mammoths. Columbian and woolly mammoths also showed evidence of interbreeding, likely following a latitudinal cline across North America. While hybridization events have shaped elephantid history in profound ways, isolation also appears to have played an important role. Our data reveal nearly complete isolation between the ancestors of the African forest and savanna elephants for ∼500,000 y, providing compelling justification for the conservation of forest and savanna elephants as separate species
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