25 research outputs found

    Genome sequencing and population genomic analyses provide insights into the adaptive landscape of silver birch

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    Silver birch (Betula pendula) is a pioneer boreal tree that can be induced to flower within 1 year. Its rapid life cycle, small (440-Mb) genome, and advanced germplasm resources make birch an attractive model for forest biotechnology. We assembled and chromosomally anchored the nuclear genome of an inbred B. pendula individual. Gene duplicates from the paleohexaploid event were enriched for transcriptional regulation, whereas tandem duplicates were overrepresented by environmental responses. Population resequencing of 80 individuals showed effective population size crashes at major points of climatic upheaval. Selective sweeps were enriched among polyploid duplicates encoding key developmental and physiological triggering functions, suggesting that local adaptation has tuned the timing of and cross-talk between fundamental plant processes. Variation around the tightly-linked light response genes PHYC and FRS10 correlated with latitude and longitude and temperature, and with precipitation for PHYC. Similar associations characterized the growth-promoting cytokinin response regulator ARR1, and the wood development genes KAK and MED5A.Peer reviewe

    Genome sequencing and population genomic analyses provide insights into the adaptive landscape of silver birch.

    Get PDF
    Silver birch (Betula pendula) is a pioneer boreal tree that can be induced to flower within 1 year. Its rapid life cycle, small (440-Mb) genome, and advanced germplasm resources make birch an attractive model for forest biotechnology. We assembled and chromosomally anchored the nuclear genome of an inbred B. pendula individual. Gene duplicates from the paleohexaploid event were enriched for transcriptional regulation, whereas tandem duplicates were overrepresented by environmental responses. Population resequencing of 80 individuals showed effective population size crashes at major points of climatic upheaval. Selective sweeps were enriched among polyploid duplicates encoding key developmental and physiological triggering functions, suggesting that local adaptation has tuned the timing of and cross-talk between fundamental plant processes. Variation around the tightly-linked light response genes PHYC and FRS10 correlated with latitude and longitude and temperature, and with precipitation for PHYC. Similar associations characterized the growth-promoting cytokinin response regulator ARR1, and the wood development genes KAK and MED5A

    Streptomyces lasalocidi sp. nov. (formerly ‘Streptomyces lasaliensis’), an actinomycete isolated from soil which produces the polyether antibiotic lasalocid

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    Strain ATCC 31180T was isolated from soil collected in Hyde Park, Massachusetts (USA), and found to produce the polyether antibiotic lasalocid. The name ‘Streptomyces lasaliensis’ has been in common use since 1974, without a recognized taxonomic description. The most closely related type cultures determined by rRNA gene sequence similarity were Streptomyces longwoodensis DSM 41677T (100 %) and Streptomyces galbus DSM 40089T (100 %). OrthoANI values with S. longwoodensis and S. galbus were 95.50 and 94.41 %, respectively. Chemotaxonomic characteristics supported inclusion within the genus Streptomyces . The cell wall peptidoglycan contained ll-diaminopimelic acid, and the major whole-cell sugars were glucose and ribose. Polar lipids were phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylinositol, phosphatidylglycerol, one unidentified lipid and one unidentified glycolipid. The major menaquinones detected were MK9(H4), MK9(H6) and MK9(H8). The major cellular fatty acids were anteiso-C15 : 0, anteiso-C17 : 0, iso-C16 : 0, iso-C15 : 0 and anteiso-C17 : 1. Its DNA had a G+C content of 72.6 %. Differentiation of ATCC 31180T from the closely related species was evident from digital DNA–DNA hybridization values of 61.80 and 56.90 % for S. longwoodensis and S. galbus respectively. Significant differences were seen in the polyphasic phenotypic analyses. ATCC 31180T produced lasalocid, grew from 10 to 45 °C, pH4-8 and in the presence of 0–10 % NaCl, 0.01 % NaN3 and 1 % phenol. Melanin was produced; H2S and indole were not. Nitrate was not reduced. Spore chains were retinaculum-apertum and spore surfaces were smooth. Spore colour, mycelia colour and soluble pigment production were medium-dependent. The proposed name is Streptomyces lasalocidi sp. nov.; the type strain being ATCC 31180T (=NRRL 3382T=DSM 46487T).</jats:p

    Video Diary Data Collection in Research with Children: An Alternative Method

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    The study of children's experiences in relation to various life situations is an essential task that imposes certain requirements on the researcher's choice of method for data collection. In this paper the author describes the use of video diaries as a method in child research, discussing its opportunities and limitations. Although video diary studies are still not particularly widespread, their use is predicted to increase as children become increasingly familiar and comfortable with the technology. Video diaries offer a useful supplement to more conventional methods as they are capable of eliciting data that would not otherwise be obtained

    Oppfatninger om kunnskap og barrierer i smertebehandling av nyfødte

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    Background: Approximately 10 % of Norwegian newborns are each year transferred to a Neonatal Intensive Care Unit (NICU). They experience pain from numerous sources and their pain is often poorly managed. Aims: To describe health personnel?? opinions, knowledge and view of potential barriers in neonatal pain management. Materials and methods: Physicians (n=20), nurses (n=53) and nurse assistants (n=17) from two Norwegian NICUs participated. Response rate 81 %. A structured questionnaire was developed, based on an extensive literature search. Approval from the ethical committee of Southern Norway was obtained. Non-parametric statistical tests were used. Results: The respondents acquired their knowledge mainly from work place experience. Lack of knowledge was percieved as a barrier by more nurses than phycicians. Respondents see insufficient pain assessment as a barrier. Health personnel's competence in use of analgesics and comfort measures differ. The views are diverse regarding to what extent prescription and administration of analgesics are barriers to effective pain management. Conclusion: Knowledge is mainly acquired through work place experience and health personnel evaluate their competence as partly insufficient. Lack of knowledge and deficiencies in pain assessment and management were considered as barriers in pain management practices
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