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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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Vegetated soft bottoms are under pressure due to a number of anthropogenic stressors, such as coastal exploitation and eutrophication. The ecological value of these biotopes has gained recognition through international conventions and the EU directives, which request methods for assessment of the environmental status of coastal areas. However, currently there is no appropriate method for assessing the status of shallow vegetated soft bottoms in the northern Baltic Sea. Therefore, we developed a macrophyte community index and tested its response in relation to important pressures (eutrophication and boating activity) and natural gradients (topographic openness, depth and salinity) on shallow bays in the northern Baltic Sea. The macrophyte index, and hence the proportion of sensitive to tolerant species, decreased with increasing phosphorus concentration, turbidity and level of boating activity, while the cumulative cover of macrophytes only showed a negative trend in response to increasing turbidity. Juvenile fish abundance was positively related to the index, indicating importance of sensitive macrophyte species for ecosystem functioning. As the index was tested in a wide geographic area, and showed a uniform response across natural gradients, it is a promising tool for assessment of environmental status that may be applied also in other vegetated soft-bottom areas. 相似文献
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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