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1.
Isolation by oceanic distance and spatial genetic structure in an overharvested international fishery 下载免费PDF全文
Nathan K. Truelove Stephen J. Box Karl A. Aiken Azra Blythe‐Mallett Erik M. Boman Catherine J. Booker Tamsen T. Byfield Courtney E. Cox Martha H. Davis Gabriel A. Delgado Bob A. Glazer Sarah M. Griffiths Kimani Kitson‐Walters Andy S. Kough Ricardo Pérez Enríquez Richard F. Preziosi Marcia E. Roy Iris Segura‐García Mona K. Webber Allan W. Stoner 《Diversity & distributions》2017,23(11):1292-1300
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Lauren Porter Jennifer Duke Meredith Hennon David Dekevich Erik Crankshaw Ghada Homsi Matthew Farrelly 《PloS one》2015,10(5)
Recent youth trends in the prevalence of e-cigarette and traditional cigarette use in Florida were examined in a cross-sectional, representative state sample from 2011 to 2014. Traditional cigarette use among youth declined during the study period. Experimentation with and past 30-day use of e-cigarettes among Florida youth tripled over 4 years. Past 30-day e-cigarette use exceeded traditional cigarette use in 2014; 10.8% of high school and 4.0% of middle school students reported recent e-cigarette use, compared with 8.7% of high school and 2.9% of middle school students for traditional cigarettes (P<0.001). By 2014, 20.5% of high school and 8.5% of middle school students reported ever use of e-cigarettes. Among ever e-cigarette users in 2014, 30.3% of high school and 42.2% of middle school students had never smoked traditional cigarettes. Given the concern that significant rates of e-cigarette use by U.S. adolescents may have a negative effect on public health, further review of e-cigarette advertising, marketing, sales, and use among U.S. youth is warranted. 相似文献
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Maria B. Olsen Gunn A. Hildrestrand Katja Scheffler Leif Erik Vinge Katrine Alfsnes Vuk Palibrk Junbai Wang Christine G. Neurauter Luisa Luna Jostein Johansen Jonas D.S. Øgaard Ingrid K. Ohm Geir Slupphaug Anna Kuśnierczyk Arnt E. Fiane Sverre-Henning Brorson Lili Zhang Lars Gullestad Alexandra V. Finsen 《Cell reports》2017,18(1):82-92
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Frankia is the diverse bacterial genus that fixes nitrogen within root nodules of actinorhizal trees and shrubs. Systematic and ecological
studies of Frankia have been hindered by the lack of morphological, biochemical, or other markers to readily distinguish strains. Recently,
nucleotide sequence of 16 S RNA from the small ribosomal subunit has been used to classify and identify a variety of microorganisms.
We report nucleotide sequences from portions of the 16 S ribosomal RNA from Frankia strains AcnI1 isolated from Alnus viridis ssp. crispa (Ait.) Turrill and PtI1 isolated from Purshia tridentata (Pursh) DC. The number of nucleotide base substitutions and gaps we find more than doubles the previously reported sequence
diversity for the same variable regions within other strains of Frankia. 相似文献
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Olle Anderbrant Jan Lfqvist Hans-Erik Hgberg Erik Hedenstrm 《Entomologia Experimentalis et Applicata》1995,74(1):83-90
Mating disruption of the pine sawflyNeodiprion sertifer (Geoffroy) (Hymenoptera: Diprionidae) was strongly indicated by reduced male trap catches in pine plantations permeated with
the sex phermone, (2S, 3S, 7S)-diprionly acetate. The trap catch reduction was 95 to near 100% when dispensers every 10 m were used, giving a total release
of about 3 mg per hectare and day. Two mg of pheromone per cotton roll dispenser maintained low catches for the whole season
(about 2 months) without any renewal of disruption dispensers. Anerythro-mixture was as effective as the pure pheromone isomer. The effects of the experiments on population density and sex ratio
were not possible to investigate, due to a general collapse of the population, also outside experimental plots, the year after
the experiments. 相似文献
10.
Comparative mitochondrial and chloroplast genomics of a genetically distinct form of Sargassum contributing to recent “Golden Tides” in the Western Atlantic 下载免费PDF全文
Linda A. Amaral‐Zettler Nicholas B. Dragone Jeffrey Schell Beth Slikas Leslie G. Murphy Clare E. Morrall Erik R. Zettler 《Ecology and evolution》2017,7(2):516-525
Over the past 5 years, massive accumulations of holopelagic species of the brown macroalga Sargassum in coastal areas of the Caribbean have created “golden tides” that threaten local biodiversity and trigger economic losses associated with beach deterioration and impact on fisheries and tourism. In 2015, the first report identifying the cause of these extreme events implicated a rare form of the holopelagic species Sargassum natans (form VIII). However, since the first mention of S. natans VIII in the 1930s, based solely on morphological characters, no molecular data have confirmed this identification. We generated full‐length mitogenomes and partial chloroplast genomes of all representative holopelagic Sargassum species, S. fluitans III and S. natans I alongside the putatively rare S. natans VIII, to demonstrate small but consistent differences between S. natans I and VIII (7 bp differences out of the 34,727). Our comparative analyses also revealed that both S. natans I and S. natans VIII share a very close phylogenetic relationship with S. fluitans III (94‐ and 96‐bp differences of 34,727). We designed novel primers that amplified regions of the cox2 and cox3 marker genes with consistent polymorphic sites that enabled differentiation between the two S. natans forms (I and VIII) from each other and both from S. fluitans III in over 150 Sargassum samples including those from the 2014 golden tide event. Despite remarkable gene synteny and sequence conservation, the three Sargassum forms differ in morphology, ecology, and distribution patterns, warranting more extensive interrogation of holopelagic Sargassum genomes as a whole. 相似文献